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November 10, 2020
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https://www.sciencedaily.com/releases/2020/11/201110112525.htm
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Chronic stress causes genetic changes in chickens
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How can stress in animals be measured? Scientists from Uppsala University and elsewhere have now found that what are known as epigenetic biomarkers could be used to detect long-term exposure to stress in commercially raised chickens. This may, in time, lead to improved conditions in animal rearing. The study has been published in the journal
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Subjected to chronic stress, animals show deterioration in their general state of health and a weakened immune system, which is unfortunate in terms of animal protection. For commercial animal production, it means that animal products are of a lower quality and a larger quantity of meat has to be discarded. These repercussions, in turn, adversely affect farmers' finances and consumers' food quality. Nonetheless, there are currently no reliable ways of measuring long-term stress in animals.Researchers from Sweden and Brazil have now, in chicken studies, looked for signs of how chronic stress can affect the genes of red blood cells, causing "epigenetic changes." In brief, this means that specific molecule types ("methyl groups") attach themselves to different parts of the DNA strand ("methylation"), depending on how the animal has lived. This may exert long-term effects on gene expression. Genes can, for example, be turned on or off (activated or deactivated).The chickens studied, males of the popular White Leghorn breed of laying birds, were divided into two groups. One group was raised in a normal commercial environment, housed with other chickens and with good access to food and water. In the other group, the birds were exposed to factors known to induce stress. They were periodically isolated from one another, with also limited access to food and water. The same experiment was performed in both Sweden and Brazil."We took blood samples from the chickens in both the control group and the stress group after the stress treatment ended. We analysed the methylation of red blood cells and compared methylation patterns in the two groups," says Fábio Pértille of the University of São Paulo, the first author of the study.What they then saw was that in the stressed birds, the way in which the methyl groups had bound to the DNA of the red blood cells was entirely different from how this occurred in the control chickens. Although the scientists were unable to see how long these changes persisted, they were nonetheless an indication that the chickens had been exposed to prolonged stress."It's early days, but the results from this study are a step towards being able to identify specific epigenetic biomarkers that are evidence of the stress imposed on commercially raised animals in their living environment. It would be highly useful to have a diagnostic tool for tracking recurrent stress in production animals. And that could bring about, for example, improved health and protection for farmed animals; meat and dairy products of higher quality; and reduced use of antibiotics," says Carlos Guerrero-Bosagna, a researcher in environmental toxicology at Uppsala University.
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Agriculture & Food
| 2,020 |
November 9, 2020
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https://www.sciencedaily.com/releases/2020/11/201109124720.htm
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The ecology of crop pests
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As agriculture in the United States evolves, it's becoming more intensive and less complex. That means larger fields, more cropland and less crop diversity with fewer crops in rotation.
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Ecological theory generally holds that diversity promotes stability in biological systems. Ashley Larsen, an assistant professor at UC Santa Barbara's Bren School of Environmental Science & Management, was curious how these tenets translate to agricultural landscapes, particularly with respect to crop pests.Larsen and her colleague Frederik Noack, at the University of British Columbia, analyzed 13 years of data from Kern County, California -- which consistently tops lists of the nation's most valuable agricultural counties -- and discovered that less diverse croplands led to greater variability in pesticide use as well as to higher peak pesticide application. Their findings appear in the journal The idea that greater diversity stabilizes an ecosystem emerged around the 1940s, relatively early in the development of ecology as a field. The theory has encountered some skepticism throughout the years, and there's recently been a resurgence of interest in investigating this relationship.Kern County provided a fantastic opportunity for the two researchers to study the phenomenon; in this case, how changes in crop and landscape diversity affect populations of crop pests."The U.S. has seen a shift toward larger agricultural enterprises," said Larsen. "So instead of small family farms we now have much bigger agricultural conglomerates." That has accompanied the trend of increasing field size and decreasing crop diversity. She suspects these all relate back to farmers taking advantage of the economy of scale.Although Kern keeps extensive agricultural records, no one tracks the populations of pests, per se. This meant the researchers had to use a proxy: insecticide use. Only later did they appreciate how much this decision expanded the implications of their findings."Once you introduce insecticides into the study, then it's not just about diversity and stability in this ecological theory," Larsen said. "Now it has implications for environmental impacts and food security."Larsen and Noack scoured the county records from 2005 through 2017 focusing on factors such as field size, as well as the amount and diversity of croplands. What they saw seemed to sync with their predictions. "We find increasing cropland in the landscape and larger fields generally increase the level and variability of pesticides, while crop diversity has the opposite effect," the authors wrote.As field size increases, the area gets larger more quickly than the perimeter. This means that smaller fields have proportionally larger perimeters. And a larger perimeter may mean more spillover from nearby predators like birds, spiders and ladybugs that eat agricultural pests.Smaller fields also create more peripheral habitat for predators and competitors that can keep pest populations under control. And since the center of a smaller field is closer to the edge, the benefits of peripheral land in reducing pests extends proportionally farther into the small fields.Landscapes with diverse crops and land covers also correlated with reduced pesticide variability and overall use. Different crops in close proximity foster a variety of different pests. Though this may sound bad, it actually means that no single species will be able to multiply unimpeded."If agriculture is very simplified, there's little stopping a big outbreak of one type of pest," Larsen said. "If you're a pest in a monoculture, and that's your host crop, you have almost unlimited food resources."Larsen and Noack's findings immediately suggest strategies for increasing food production while minimizing the impact of pesticides on human health and the environment. The study could not only help farmers make more informed decisions about field size and crop diversity, but also guide policy with the aim of decreasing insecticide use.The Department of Agriculture's Farm Service Agency oversees several conservation-related programs addressing a number of different issues, including habitat preservation. Larsen suggests that tailoring these efforts to the nuances of different crop types could provide even greater benefits.What's more, these voluntary programs currently focus on efforts by individual farmers. "Based on our results, we need to think, ideally, at more of a landscape scale," Larsen said.It's difficult to untangle confounding factors in the relationship between land use and insecticide use. For instance, farmers put a lot of thought into how they plant their crops, potentially planting more valuable crops in larger fields or less diverse areas, Larsen explained. At the same time, farmers invest more in pest control, including chemical pesticides, for these high value crops, making it hard to tease apart the effect of landscape characteristics from these difficult-to-observe decisions.The authors addressed these concerns using a combination of techniques borrowed from the economics literature in an attempt to establish a more causal understanding of the relationship between landscape characteristics and insecticide use.California produces a diverse array of high-valued crops, from grapes and berries to almonds and citrus. This contrasts with regions like the Midwest and its amber waves of grain. Fields of cereals, like corn and wheat, can extend across vast swaths of the American heartland in virtual monocultures. What's more, these crops aren't nearly as valuable on a per-acre basis.All these factors influence the risks associated with pests and the economics of pesticide application. "So it's hard to say whether these results would translate well to areas with very low value cropland because the incentives to really scout your pests might be much lower," Larsen said.She has continued to investigate the effects of land use on agricultural production at both regional and national scales. In a recent paper published in the journal Landscape Ecology, she evaluated how both changing land use and climate may impact insecticide use throughout the U.S. While both are expected to increase future insecticide use, crop composition and farm characteristics are highly influential.Unfortunately, national data does not provide the same high-resolution information as Kern County, Larsen explained. She plans to continue her work to bridge the detail and scale gap to better understand how land use impacts agricultural pests and pesticide use.
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Agriculture & Food
| 2,020 |
November 6, 2020
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https://www.sciencedaily.com/releases/2020/11/201106093035.htm
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Ecologically friendly agriculture doesn't compromise crop yields
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Increasing diversity in crop production benefits biodiversity without compromising crop yields, according to an international study comparing 42,000 examples of diversified and simplified agricultural practices.
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Diversification includes practices such as growing multiple crops in rotation, planting flower strips, reducing tillage, adding organic amendments that enrich soil life, and establishing or restoring species-rich habitat in the landscape surrounding the crop field."The trend is that we're simplifying major cropping systems worldwide," says Giovanni Tamburini at the Swedish University of Agricultural Sciences and lead author of the study. "We grow monoculture on enlarged fields in homogenized landscapes. According to our study diversification can reverse the negative impacts that we observe in simplified forms of cropping on the environment and on production itself."The research, published in "By bringing together so much data, this work powerfully shows the potential for diversified farming to maintain productivity while reducing environmental harms and sustaining biodiversity and ecosystem services," says Claire Kremen at the University of British Columbia and co-author of the study."However, we need to tune these techniques to specific crops and regions, maximize these benefits and reduce trade-offs that otherwise occur. Much more investment is needed to support adoption of diversified farming practices, through research, management incentives and extension programs."Increasing biodiversity is assumed to enhance yields and ecosystem services such as pollination, pest regulation by natural enemies, nutrient turnover, water quality and climate change mitigation by carbon sequestration. Although much research has been invested to explore this, outcomes of diversification had not previously been synthesized. Further, the focus had mainly been diversification of crops and vegetation. Diversification of soil organisms is seldom recognized."An important next step is to identify which practices and conditions that result in positive or negative climate mitigation, and to avoid practices that give negative impacts," says Sara Hallin at the Swedish University of Agricultural Sciences and co-author of the study.Studies where yield had been examined together with one or more other ecosystem services were few but still many enough to analyze occurrence of win-win, trade-off and lose-lose situations. Win-win outcomes between yield and another service dominated with 63 % of the cases, but all other possible outcomes (i.e. representing tradeoffs between yield and ecosystem services) were also represented.Many of the tested diversification practices are in use already today, but can be more widely adopted and combined both on and off the crop field.There are many ways to increase diversity both on and off the crop field. Farms can add crop species to crop rotations, or grow crops together in the same field with intercropping. Flowering crops provide pollen and nectar for pollinating and predatory insects. Farms can also support below-ground biodiversity by mulching crop residues and adding manure or minimizing soil disturbance by reducing tillage.
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Agriculture & Food
| 2,020 |
November 5, 2020
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https://www.sciencedaily.com/releases/2020/11/201105113031.htm
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Biological clock and extra gene pairs control important plant functions
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The biological clock of a popular food crop controls close to three-quarters of its genes, according to research from Dartmouth College.
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The genetic research shows how the crop uses internal responses to the day-night cycle -- known as circadian rhythms -- to regulate processes such as reproduction, photosynthesis and reactions to stressful conditions.The study, published in the journal "As plants are cultivated in new geographic zones they must select traits that enable them to survive in different conditions," said C. Robertson McClung, a professor of biology at Dartmouth and senior researcher on the study. "Many of these traits are in circadian clock genes."Like animals, plants have biological clocks that allow them to adapt to predictable changes, such as day-night cycles or the shift in seasons. While animals can relocate to adapt to such environmental changes, plants are stuck in place. To survive, plants need to activate and deactivate genes to alter their biological functions.The research team used RNA-sequencing to identify how genes in the popular crop Brassica rapa are controlled by the plant's internal time-keeping mechanism. The B. rapa species includes varieties such as turnips, oilseed, Chinese cabbage and leafy vegetables.In the study, plants were exposed to normal conditions featuring warm days and cool nights. They were then removed from this environment and sampled over a two-day period to reveal which genes were active in response to signals from the plant's internal clock.The research found that over 16,000 genes, about three-quarters of all of the plant's genes, are regulated by circadian rhythms in the absence of light and temperature changes."We were surprised to find that such a high number of genes are regulated by the biological clock. This emphasizes the importance of circadian clock control of many functions within the plant," said McClung.Many crop plants, such as wheat, potatoes and Brassica, have doubled or tripled their complete complements of genes. This led researchers to question what effect the additional gene pairs have on the plant's biological clock, or on survival processes such as resilience to drought.The research team found that the extra gene copies are often active at different times of day from their gene pairs.In addition, the researchers found that often only one member of a pair of duplicated genes responded to drought. In both these cases, the differences in timing of gene activation, or in drought-responsiveness, must have occurred after the genes had duplicated.The findings lead to the conclusion that the same gene duplication that is responsible for a more sensitive biological clock also creates more drought resistance."During the evolution of land plants, the number of gene pairs expanded," said Kathleen Greenham, an assistant professor of plant and microbial biology at the University of Minnesota who co-led the study as a postdoctoral researcher at Dartmouth. "One set of copies can maintain critical growth processes while the others are free to evolve new functions that researchers can use to produce stress-resilient crops."Identifying the differences within gene pairs that cause them to be responsive or non-responsive to drought conditions could give researchers a way of helping plants increase resilience to climate-induced changes."Time of day matters for gene expression when it comes to dealing with drought," said Ryan Sartor, a postdoctoral researcher at North Carolina State University who co-led the study. "This is an early step to help understand basic relationships. A more complete understanding of this complex system could lead toward the development of more stress-resistant crops."According to the research team, the circadian rhythms that regulate much of plant biology are likely to be influenced by climate change since environmental cues become less reliable. This makes it harder for plants to adapt and survive, but it also serves as a clue for researchers searching for ways to build plant resilience.
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Agriculture & Food
| 2,020 |
November 5, 2020
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https://www.sciencedaily.com/releases/2020/11/201105112940.htm
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Host genetic factors shape composition of virus communities
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Plants can be infected by multiple viruses at once. However, the composition of the pathogen community varies, even if individuals belong to the same species and the same population. Ecologists at the University of Zurich have now shown that these differences are primarily due to genetic variation among the hosts. The loss of genetic diversity could thus render species more vulnerable to infections and extinction.
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Viruses are ubiquitous across the plant and animal kingdoms -- but most of them are still unknown to science. Researchers have only recently developed improved analysis techniques and statistical tools to tackle one of the key questions: Why are some individuals more susceptible to viruses, while others remain unharmed?It is already known that genetic differences can make animals or plants more resistant to a specific virus. However, it is becoming increasingly clear that most organisms do not only harbor one kind of pathogen but complex communities made up of different microbes. "Accounting for this diversity of infection is necessary to understand and predict disease dynamics and costs of infection for the host," says Professor Anna-Liisa Laine from the Department of Evolutionary Biology and Environmental Studies at the University of Zurich. For example, the first arriving pathogen could confer resistance to a second pathogen. But so far, little is known about the factors that shape the composition of virus communities.With her research team at the Universities of Zurich and Helsinki, Laine has now shown that genetic differences have a major impact on the diversity of the virus community each individual supports. "This suggests that depletion of genetic diversity within a species can have significant consequences for the risk of virus infection," says Laine.For their study, the team used the common weed Plantago lanceolata, also known as ribwort plantain. Individuals of this plant can be cloned by propagation of the roots -- resulting in genetically identical offspring. With this method, the researchers generated 80 clones from each of four different genetic variants of ribwort plantain and placed them among populations of naturally occurring ribwort plantain at four locations in the Åland archipelago in the Baltic Sea. The cloned plants were thus exposed to virus attacks under natural conditions. "By placing identical plants in different environments and keeping everything else constant, we could rigorously test the role of genetics," explains Laine.After two and seven weeks respectively, the researchers collected leaves and determined which of five frequently occurring plant viruses had infected the clones. They found that about two thirds of the plants were infected with at least one virus, while almost a quarter of those carried multiple viruses. Altogether, they found 17 different combinations, ranging from two to five viruses per plant.Sophisticated statistical modelling then allowed the researchers to discern how strongly the various factors ? genetics, location, plant size, damage by herbivores and interaction among the viruses -- influenced the composition of the virus communities. The results revealed that host genetic differences explained most of the observed variation. "Although we had suspected that genotype would play a role, we were very surprised that it turned out to be the most important determinant," says Laine. Another important factor was the local environment, whereas others such as plant size and herbivores showed only minor effects."This demonstrates for the first time that genetic differences, most likely in immunity genes, are critical for how these diverse pathogen communities assemble inside hosts," says Laine. "One of the next steps will now be the identification of the underlying genes."The results highlight the importance of genetic diversity within species. The loss of diversity makes species much more susceptible to virus infections, with far-reaching consequences for biodiversity. The genetic diversity of natural populations is already being increasingly depleted due to human destruction of natural habitats.According to Laine, these findings could also be applied in agriculture to improve pathogen resistance in crop plants: "Incorporating genetic diversity to crop systems should be embraced as a sustainable means of controlling disease in agriculture. Not only individual pests, but entire communities of pathogens."This research is supported by European Research Council (ERC) funding awarded to Laine to investigate how host resistance functions and evolves under diverse virus attack.
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Agriculture & Food
| 2,020 |
November 4, 2020
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https://www.sciencedaily.com/releases/2020/11/201104121442.htm
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Beetles cooperate in brood care
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They belong to the bark beetle family, and they are the only animals in nature, along with leaf-cutter ants and some termites, that practice agriculture: ambrosia beetles. These insects, which are about two millimetres in size, carry fungal spores into their nests and sow them in specially created tunnels in the wood. They then care for the growing fungal cultures that serve as food for them.
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Like farmers, the beetles also have to defend their fungal cultures against pests, such as other fungi that threaten to overgrow the gardens. Individually living beetles could hardly manage this work. This is why ambrosia beetles have developed sophisticated social systems over the course of evolution, similar to those of bees and other social insects. "This is unique in beetles," says Würzburg biologist Peter Biedermann.Biedermann is fascinated by ambrosia beetles. He studied them at the Biocentre of Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany. "Because they have been practicing this type of sustainable agriculture for 60 million years, I am interested in how they combat harmful fungi. Perhaps we can learn from the beetles for our own agriculture."Ambrosia beetles are spread all over the world. In the case of the Fruit-tree pinhole borer (Xyleborinus saxesenii) native to Europe and invasive worldwide, Biedermann described an extraordinarily highly developed social system already in 2011 (publication Biedermann & Taborsky, PNAS). He has now found a similar social system in the sugercane shot-hole borer Xyleborus affinis, which lives in the tropics of the Americas. No other beetles with this peculiarity are known so far.Biedermann presents his new findings on the social system of the American beetle in the magazine Frontiers in Ecology & Evolution: After a beetle mother has established a new nest with fungal gardens and the first offspring develops, many young beetles stay with their mother for the time being. They help her to care for the fungi and to raise the offspring.This is comparable to the workers of the bees. "In contrast to the sterile bee workers, however, the female beetle workers are capable of reproduction: depending on their life situation, they decide whether they will eventually establish their own nest, whether they will lay eggs in the birth nest themselves or whether they will exclusively help the mother," says the biologist.This social system is termed cooperative brood care, which is very rare in nature and is a preliminary stage to the eusocial system of social insects with their sterile workers and a fertile queen. These beetles could help science to understand the evolution of sociality. Abundance of "weed fungi" determines activityIn his study, Biedermann has also discovered new information about the sugercane shot-hole borers farming activities. The beetles adjust their fungal care behaviour according to whether there are many or few "weed fungi" growing in the nest. Furthermore, it was shown that beetle daughters who do not reproduce themselves help with the work in the nest, but otherwise show less social behaviour than their egg-laying sisters.Peter Biedermann recently took over the professorship for forest entomology and forest protection at the University of Freiburg in Germany. His next step there will be to investigate whether ambrosia beetles can distinguish between weedy and food fungi on the basis of their odour and how the beetles selectively weed or chemically control the fungal weeds.
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Agriculture & Food
| 2,020 |
November 3, 2020
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https://www.sciencedaily.com/releases/2020/11/201103104730.htm
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Ants swallow their own acid to protect themselves from germs
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Ants use their own acid to disinfect themselves and their stomachs. A team from Martin Luther University Halle-Wittenberg (MLU) and the University of Bayreuth has found that formic acid kills harmful bacteria in the animal's food, thereby reducing the risk of disease. At the same time, the acid significantly influences the ant's intestinal flora. The new study was published in the journal
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Formic acid is one of the simplest organic acids. It is produced in a special gland in the abdomen of numerous species of ant. "There was a long-standing assumption that the acid only served to ward off predators, for example insects and birds," says Dr Simon Tragust from the Institute of Biology at MLU, who co-led the new study alongside Professor Heike Feldhaar from Bayreuth. A couple of years ago he was able to show that ants also use the acid in brood care, for example, to disinfect their brood and prevent the spread of harmful fungi.The new study was based on an observation of the animals' behaviour. "Whenever ants swallow food or water, they start cleaning their hindquarters afterwards," says Tragust. The researcher wanted to figure out why they do that. "For one thing, the behaviour didn't seem to be linked to digestion, because ants do this even after they have only ingested water," he adds.Through several experiments the team was able to show that ants disinfect themselves on the inside. "When the ants were able to access the acid, their chances of survival increased significantly after eating food enriched with pathogenic bacteria," explains Tragust. What's more, the beneficial effect was not limited to an individual animal. Ants pass food from their mouth to the mouths to their nest mates. "This is a major potential source of infection," says Tragust. If the ant passing on the food has previously ingested the acid, the receiving ant had a lower risk of falling ill. According to Tragust, this behaviour might reduce the spread of infection within the ant colony.The results of the new study also explain why some ants have very few bacteria in their digestive tracts; those that are present are primarily acid-resistant microbes. "Acid swallowing acts as a filter mechanism, structuring the ant's microbiome," explains Tragust. Ants are one of just a handful of animals with extremely acidic stomachs. "Otherwise this is only known to occur in humans and a few other vertebrates," says Tragust. Unlike ants, stomach acid in humans is produced directly in the stomach, but the effects are the same: The acid kills germs in the food and influences the microbiome of the gut.Incidentally, how formic acid precisely works is still a mystery, but it and other organic acids have long been used as additives in animal feed to kill harmful germs.
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Agriculture & Food
| 2,020 |
November 3, 2020
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https://www.sciencedaily.com/releases/2020/11/201103104721.htm
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Plant viruses hijack the defense system of plants, but there might be a way to strike back
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Many diseases caused by common plant viruses reduce the crops of important food plants. In the worst case, potato viruses, among others, can destroy as much as 80% of crops on infected fields.
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Plants are not entirely defenceless against viruses, although they lack an immune system like the one found in humans. For plant cells, the primary defence mechanism against viral infections is gene silencing. By utilising the mechanism, plant cells identify the foreign genetic material originating in the virus and cut it up into small pieces."In turn, these bits of the genome guide plant cell proteins to identify and destroy viral genomes. As a result, the production of viral proteins ends, which is interpreted as 'silencing' of the viral genes. A successful defensive response prevents the virus from spreading in the plant," says Docent Kristiina Mäkinen from the Faculty of Agriculture and Forestry, University of Helsinki.At the same time, viruses too have means with which to resist and subvert the host plant's defence mechanisms. A research group specialised in plant virology, led by Mäkinen, investigates the interaction between potato virus A and host plant proteins. Mäkinen and her group find one viral protein particularly interesting, as it is directed against the plant's defence system."This protein is able to not only block gene silencing, but also to harness the factors involved in the process to serve both its viral replication and the formation of new viral particles. In other words, the virus forces, as it were, the plant's defence system to go against its intended purpose, in favour of the pathogen."Studies on plants that are naturally resistant to viruses have shown that their resistance is often based on mutations in the plant's genome that block interaction between viral and plant proteins. To employ these mutations in plant breeding, University Researcher Maija Pollari considers it necessary to start utilising modern plant breeding techniques."For instance, the CRISPR/Cas9 technique, which was just awarded the Nobel Prize in Chemistry, makes it possible to target anti-viral mutations in a precise location in the plant genome. This is a great stride forward compared to traditional plant breeding, which relies on the use of mutagenic chemicals and radioactive radiation," Pollari adds.The interactions between plant and viral proteins discovered by Kristiina Mäkinen's research group offer new targets for breeding resistance against the potato virus in host plants. The researchers' aim is to identify a component in the plant proteins through which they come into contact with viral proteins."When proteins are modified so that the interaction is blocked, the plant's gene silencing mechanism may regain the upper hand over the virus. Strains resistant to viruses used in cultivation reduce losses caused by viral diseases and, consequently, improve yields. Furthermore, it's likely that the chemical burden of the environment is alleviated, as the amount of chemicals used in preventing aphids is reduced," notes Kristiina Mäkinen.
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Agriculture & Food
| 2,020 |
November 2, 2020
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https://www.sciencedaily.com/releases/2020/11/201102120113.htm
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Fighting food fraud from farm to fork with a mobile ingredient tracing system
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Savvy shoppers increasingly expect to know the origin of the food they eat, whether they shop at farmers' markets or big-box major retailers. A prototype app proposed by researchers at the University of Tokyo aims to provide full transparency from farm to table along food supply chains and meet the needs of smallholder farmers, boutique producers, and industrial growers.
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Official food certification systems exist in many countries, but experts say the financial cost of implementation and the labor costs of maintenance are impractical for small-scale producers. Existing certifications systems can also be exploited by unscrupulous sellers who fake certificates or logos of authenticity for premium products, like Japanese wagyu beef and Italian Parmigiano Reggiano cheese, or for environmentally ethical products, like dolphin-safe tuna."Our motivation was to design a food tracking system that is cheap for smallholder farmers, convenient for consumers, and can prevent food fraud," said Kaiyuan Lin, a third-year doctoral student at the University of Tokyo and first author of the research study published in The research team's food tracking system begins with the harvest of any ingredient, for example, rice on a family farm. The farmer opens the app on a mobile phone, enters details about the amount and type of rice, then creates and prints a QR code to attach to the bags of rice. A truck driver then scans the QR code and enters details into the app about where, when, and how the rice was transported to the market. A market vendor buys the rice, scans the QR code to register that the rice is now in their possession, and enters details about where and how the rice is stored before resale. Eventually, the vendor might sell some rice directly to consumers or other manufacturers who can scan the QR code and know where the rice originated."My mission is to make sure the system is not lying to you. Data are recorded in our digital system only when transactions happen person-to-person in the real, physical world, so there can be no fraud," said Lin.If an imposter registered counterfeit QR codes to dupe consumers, farmers would notice that their alleged harvest size suddenly duplicated itself in the app. Farmers can also choose to receive updates from the app about where, when, and in what form their harvest eventually reaches consumers."We think tracking their ingredients will appeal to farmers' sense of craftsmanship and pride in their work," said Lin.The app can also turn a long list of ingredients into a single QR code. For example, a factory chef might buy rice from Taiwan, Kampot pepper from Cambodia and Kobe beef from Japanto manufacture into prepared meal kits. Only when physically receiving these ingredients can the factory record to their QR codes. After collecting all of the ingredients' codes, the factory then uses the app to create a new QR code to attach to the completed meal kits. The factory can create a unique QR code for each new batch of meal kits every day. When consumers scan a meal kit's QR code, they can read details about the kit as well as all of the origin of all the individual ingredients that are digitally connected to the kit's QR code."The current barcode system means that every day of the year, forever, when you buy the same product, it will have the same barcode. Our system means small producers making small batches can generate a new QR code for each batch," said Lin. This increased level of detail can also help regulators track food safety and manage any safety recalls more efficiently and precisely.The app was designed with open-source software and a fully decentralized (peer-to-peer or multi-master) database, meaning that changes are not controlled by a centralized server. Data storage is spread out among every user's phone or computer, so there is no central server to hack, providing consumers with even more peace of mind. Researchers hope the decentralized aspect of the app will further contribute to democratizing food systems.For now, the app remains a hypothetical proposal in need of further financial support to become a reality."We have created a prototype demonstration of the infrastructure for a new system of accurate food traceability. Before we can all use the app on our next grocery shopping trip, computer coders and user interface designers will have to build the app and farmers will need printers for QR code stickers," said Lin.This research is a collaborative project with Complex Systems Institute of Paris Île-de-France, French National Centre for Scientific Research (CNRS).
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Agriculture & Food
| 2,020 |
November 2, 2020
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https://www.sciencedaily.com/releases/2020/11/201102120103.htm
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Hungry plants rely on their associated bacteria to mobilize unavailable iron
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In nature, healthy plants are awash with bacteria and other microbes, mostly deriving from the soil they grow in. This community of microbes, termed the plant microbiota, is essential for optimal plant growth and protects plants from the harmful effects of pathogenic microorganisms and insects. The plant root microbiota is also thought to improve plant performance when nutrient levels are low, but concrete examples of such beneficial interactions remain scarce. Iron is one of the most important micronutrients for plant growth and productivity. Although abundant in most soils, iron's poor availability often limits plant growth, as it is found in forms that cannot be taken up by plants. Thus, adequate crop yields often necessitate the use of chemical fertilizers, which can be ecologically harmful in excessive application. Now, MPIPZ researchers led by Paul Schulze-Lefert have uncovered a novel strategy employed by plants to overcome this problem: they release substances from their roots that direct plant-associated bacteria to mobilise soil iron so that plants can easily take it up.
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When confronted with iron in unavailable forms, plants mount a compensatory response to avoid iron deficiency. This starvation response involves extensive reprogramming of gene expression and the production and secretion of coumarins, aromatic compounds that are discharged from plant roots and which themselves can improve iron solubility. Interestingly, it was recently shown that coumarins are a selective force, shaping the composition of plant-associated bacterial communities. Now, it emerges that some coumarins also act as an "SOS" signal that prompts the root microbiota to support plant iron nutrition.To first assess the contribution of the root microbiota to iron-limiting plant performance, first-author Christopher Harbort and colleagues used a controlled system which allowed them to regulate the availability of iron as well as the presence of root-associated bacteria. Using the laboratory model thale cress, they compared plants completely lacking bacteria and ones with an added synthetic community (SynCom) of bacterial commensals which reflects the root bacterial diversity observed in nature. The authors found that addition of this bacterial SynCom strongly improved the performance of plants grown on unavailable iron but not those grown with iron that was readily available. Growing plants in associations with single bacterial strains allowed them to determine that this iron-rescuing capacity is widespread among bacteria from different bacterial lineages of the root microbiota. When the researchers performed the same experiments with plants compromised in the production or secretion of coumarins, the community of bacteria provided no benefits. Thus, they could show that plant-secreted coumarins are responsible for eliciting nutritional assistance from bacterial commensals under iron limitation.The authors' findings strongly suggest that the root microbiota is an integral part of how plants adapt to growth in iron-limiting soil. Furthermore, by identifying the plant-to-microbe signal for assistance, this research brings us one step closer to harnessing naturally present soil bacteria as a substitute for synthetic fertilizers. Improving plant iron nutrition could not only improve agricultural yields, but also increase the nutrient content of staple food crops, a potential strategy for tackling iron deficiency in humans as well.
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Agriculture & Food
| 2,020 |
November 2, 2020
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https://www.sciencedaily.com/releases/2020/11/201102120046.htm
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Silk road contains genomic resources for improving apples
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The fabled Silk Road -- the 4,000-mile stretch between China and Western Europe where trade flourished from the second century B.C. to the 14th century A.D. -- is responsible for one of our favorite and most valuable fruits: the domesticated apple (Malus domestica).
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Snack-packing travelers would pick apples at one spot, eat them and toss their cores many miles away. The seeds grew into trees in their new locations, cross-bred with the wild species, and created more than 7,000 varieties of apples that exist today.Hybridizations with wild species have made the apple genome very complex and difficult to study. A global team of multi-disciplinary researchers -- co-led by Zhangjun Fei, faculty member at Boyce Thompson Institute (BTI), and Gan-Yuan Zhong, scientist with the USDA-Agricultural Research Service (ARS) in Geneva, New York -- tackled this problem by applying cutting-edge sequencing technologies and bioinformatics algorithms to assemble complete sets of both chromosomes for the domesticated apple and its two main wild progenitors.The researchers discovered that the apple's unique domestication history has led to untapped sources of genes that could be used for crop improvement, such as improving size, flavor, sweetness and texture."Plant breeders could use this detailed information to improve upon traits that matter most to consumers, which today is primarily flavor," says Fei, also an adjunct associate professor in Cornell University's School of Integrative Plant Science (SIPS)."Perhaps more importantly," he added, "the information will help breeders produce apples that are more resistant to stress and disease."The research is described in a paper published in According to Fei, the new study was the outgrowth of an earlier collaboration, published in Follow-up discussions among Fei, Zhong and other colleagues at Cornell, inspired them to build better and new apple reference genomes by applying new sequencing and assembly technologies to material in USDA's Geneva Clonal Repository. The repository, which is housed at Cornell AgriTech, holds the largest collection of apple accessions in the world. Many of these accessions can be traced back to the Silk Road.In the current work, the researchers sequenced, assembled and compared the full reference genomes for three species: Gala, a top commercial cultivar of M. domestica; and apple's two main wild progenitors, the European crabapple (M. sylvestris) and the central Asian wild apple (M. sieversii), which together account for about 90% of the domesticated apple's genome.The results provide apple breeders with detailed genomic roadmaps that could help them build a better apple."We wanted to develop new genomes, especially the wild progenitors, because of the tremendous impact they could have on understanding apple's genetic diversity and identifying useful traits for breeding new cultivars," said Zhong, who is also an adjunct associate professor in SIPS.By comparing the three genomes, the researchers were able to identify which progenitor species contributed the genes responsible for many traits in the domesticated apple. For example, the team found that the gene giving apple its crunchy texture is located near the gene that makes it susceptible to blue mold."Now that we know exactly where those two genome regions are," Fei said, "breeders could figure out a way to keep the texture gene and breed out or edit out the blue mold gene to produce a more disease-resistant cultivar."The team also assembled pan-genomes for the three species. A pan-genome captures all of the genetic information in a species, unlike a reference genome that captures one individual organism. Pan-genomes are especially important for a very diverse species like apple.The team identified about 50,000 genes in the pan-genome of the domesticated apple, including about 2,000 that were not present in previously published reference genomes for apple species. "These 'missing genes' turn out to be really important, because many of them determine the traits of greatest interest to apple breeders," Fei said.Using RNA extracted from different stages of Gala fruits, they also identified genes linked to texture, aroma and other fruit characteristics that were preferentially expressed between the two copies of the genes."That provides us and breeders with an even deeper understanding of the genetic diversity underlying a particular trait," Zhong said. "The findings will help our group better manage and curate more than 6,000 apple accessions in the USDA Geneva Clonal Repository," Zhong adds, "as well as enable us to provide critical genetic and genomic information associated with the accessions to breeders and other researchers."The team is planning on sequencing other wild apple species, which Fei says may have valuable traits that could improve stress-resistance and resilience in the domesticated apple.The research was supported by a Non-Assistance Cooperative Agreement between USDA-ARS and BTI (No. 58-8060-5-015), and by grants from the U.S. National Science Foundation (IOS-1855585 and IOS-1339287).
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Agriculture & Food
| 2,020 |
October 30, 2020
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https://www.sciencedaily.com/releases/2020/10/201030111835.htm
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Waste not, want not: Recycled water proves fruitful for greenhouse tomatoes
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In the driest state in the driest continent in the world, South Australian farmers are acutely aware of the impact of water shortages and drought. So, when it comes to irrigation, knowing which method works best is vital for sustainable crop development.
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Now, new research from the University of South Australia shows that water quality and deficit irrigation schemes each have significant effects on crop development, yield and water productivity -- with recycled wastewater achieving the best overall results.Testing different water sources on greenhouse-grown tomatoes, recycled wastewater outperformed both groundwater, and a water mix of 50 per cent groundwater and 50 per cent recycled wastewater.Researchers also confirmed that growers using deficit irrigation strategies (irrigation that limits watering in a controlled way) performs best at 80 per cent capacity, ensuring maximum water efficiency while maintaining excellent crop growth and yield levels.Lead researcher and UniSA PhD candidate, Jeet Chand, says that the findings will provide farmers with valuable insights for productive, profitable and sustainable agricultural management."Water is an extremely valuable commodity in dry and arid farming regions, making efficient irrigation strategies and alternative water sources essential for agriculture production," Chand says."Deficit irrigation is a strategy commonly used by farmers to minimise water use while maximising crop productivity but finding the most effective balance for greenhouse-grown produce can be tricky."In our research we tested optimum water deficit levels for greenhouse-grown tomatoes, showing that water at 80 per cent of field capacity is the superior choice for optimal tomato growth in the Northern Adelaide Plains."These results were enhanced by the use of recycled wastewater, which not only fares well for plants (by delivering additional nutrients) and for farmers (by reducing the need for fertilizer) but is also great for the environment."The Northern Adelaide Plains represents 90 per cent of tomato production in South Australia and contains the largest area of greenhouse coverage in the whole of Australia.This study simulated tomato growing conditions in this region across the most popular growing season and over two years. It tested groundwater, recycled wastewater and a 50:50 mix of both, across four irrigation scenarios with soil moisture levels at 60, 70, 80 and 100 per cent of field capacity.The highest growth levels were unsurprisingly achieved through 100 per cent field capacity, but mild water stress (80 per cent water capacity) delivered positive water efficiency without significant yield reduction.While the results are positive for the tomato industry, Chand says there's also good news for the home-gardening tomato aficionado."If you're one of the lucky areas to have access to a verified source of recycled water, then your garden can also benefit from its additional nutrients," Chand says."Remember, there is a significant difference between grey water -- that is, water from the bath or dishes -- and recycled water, so be sure to check your water source with your supplier."But if you have access to recycled water, great! Your tomatoes will grow like crazy, and you'll be the envy of all your neighbours."
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Agriculture & Food
| 2,020 |
October 29, 2020
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https://www.sciencedaily.com/releases/2020/10/201029141945.htm
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Study of ancient dog DNA traces canine diversity to the Ice Age
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A global study of ancient dog DNA, led by scientists at the Francis Crick Institute, University of Oxford, University of Vienna and archaeologists from more than 10 countries, presents evidence that there were different types of dogs more than 11,000 years ago in the period immediately following the Ice Age.
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In their study, published in This finding reveals that the diversity observed between dogs in different parts of the world today originated when all humans were still hunters and gatherers.Pontus Skoglund, author and group leader of the Crick's Ancient Genomics laboratory, says: "Some of the variation you see between dogs walking down the street today originated in the Ice Age. By the end of this period, dogs were already widespread across the northern hemisphere."This study of ancient genomics involves extracting and analysing DNA from skeletal material. It provides a window into the past, allowing researchers to uncover evolutionary changes that occurred many thousands of years ago.The team showed that over the last 10,000 years, these early dog lineages mixed and moved to give rise to the dogs we know today. For example, early European dogs were initially diverse, appearing to originate from two highly distinct populations, one related to Near Eastern dogs and another to Siberian dogs. However, at some point this diversity was lost, as it is not present in European dogs today.Anders Bergström, lead author and post-doctoral researcher in the Ancient Genomics laboratory at the Crick, says: "If we look back more than four or five thousand years ago, we can see that Europe was a very diverse place when it came to dogs. Although the European dogs we see today come in such an extraordinary array of shapes and forms, genetically they derive from only a very narrow subset of the diversity that used to exist."The researchers also compared the evolution in dog history to changes in human evolution, lifestyles and migrations. In many cases comparable changes took place, likely reflecting how humans would bring their dogs with them as they migrated across the world.But there are also cases when human and dog histories do not mirror each other. For example, the loss of diversity that existed in dogs in early Europe was caused by the spread of a single dog ancestry that replaced other populations. This dramatic event is not mirrored in human populations, and it remains to be determined what caused this turnover in European dog ancestry.Greger Larson, author and Director of the Palaeogenomics and Bio-Archaeology Research Network at the University of Oxford, says: "Dogs are our oldest and closest animal partner. Using DNA from ancient dogs is showing us just how far back our shared history goes and will ultimately help us understand when and where this deep relationship began."Ron Pinhasi, author and group leader at the University of Vienna, says: "Just as ancient DNA has revolutionised the study of our own ancestors, it's now starting to do the same for dogs and other domesticated animals. Studying our animal companions adds another layer to our understanding of human history."While this study provides major new insights into the early history of dog populations and their relationships with humans and each other, many questions still remain. In particular, research teams are still trying to uncover where and in which human cultural context, dogs were first domesticated.
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Agriculture & Food
| 2,020 |
October 29, 2020
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https://www.sciencedaily.com/releases/2020/10/201029104955.htm
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Bioenergy research team sequences miscanthus genome
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An international research team has sequenced the full genome of an ornamental variety of miscanthus, a wild perennial grass emerging as a prime candidate for sustainable bioenergy crops.
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The genome project -- led by scientists at the Center for Advanced Bioenergy and Bioproducts Innovation (CABBI), a Department of Energy (DOE) bioenergy research center -- provides a road map for researchers exploring new avenues to maximize the plant's productivity and decipher the genetic basis for its desirable traits.The study, published in Miscanthus grasses, also used in gardens, paper production, and roofing, are a promising source of biomass, a renewable alternative to petroleum-based fossil fuels. They belong to the Andropogoneae family of grasses, which includes maize, sorghum, and sugarcane -- highly productive and globally important plants grown as a source of food, feed, and biofuels.Miscanthus is extremely adaptable and easy to grow. It can thrive on marginal lands, requires only limited fertilization, has a high tolerance for drought and cool temperatures, and uses the more efficient C4 form of photosynthesis.The CABBI team's sequence and genomic analysis of Miscanthus sinensis -- the first for any type of miscanthus -- provide a foundation for systematic improvements to optimize those desirable traits. The project also produced an atlas of genes that are turned on and off in different parts of the plant during its seasonal life cycle, revealing new regulators of perenniality, a desirable trait for biofuel and other crops."The genomic toolkit we have assembled for miscanthus will be a valuable resource for researchers studying this plant and breeding it to improve biomass and other traits," Swaminathan said. "By comparing miscanthus with sorghum, sugarcane, and other related grasses, researchers within CABBI and beyond hope to decipher the genetic basis for innovations linked to productivity and adaptability."The study relied on extensive field collections over several growing seasons at the University of Illinois that captured the plant's full life cycle. Led by Swaminathan, scientists measured gene expression in the leaves, stems, and rhizome (the underground part of the stem). The catalog of tissue-preferred genes will provide clues for how to genetically modify the plant to improve certain processes, said Mitros, who led the computational work on genome assembly, annotation, and sequence analysis.The study also revealed a group of genes involved in the all-important nutrient remobilization cycle. In the fall, as the plant's leaves die, nitrogen and other nutrients are sent to the rhizome, where they are stored underground over the winter; in the spring, that energy is taken up into other tissues as the plant grows instead of going back into the soil, reducing the need for fertilizer. The rhizomes also produce new stems, allowing the plant to get bigger every year, and help with carbon storage. All of that makes miscanthus more sustainable -- less costly to manage and more environmentally friendly.Many M. sinensis lines are used as decorative grasses and grow both from the rhizome and from seed. The grass with bioenergy potential, Miscanthus x giganteus "Illinois" type, doesn't create viable seed and is thus more difficult to propagate. CABBI researchers like Erik Sacks, Associate Professor in the Department of Crop Sciences at Illinois, are working on new hybrids, crossing M. sinensis and M. sacchariflorus to create multiple giganteus varieties that would be more adaptable to different regions and produce seeds.The genetic sequence is a platform to understand the variations within all kinds of miscanthus varieties, Rokhsar said. Miscanthus hybrids have evolved naturally in Asia, and Sacks and other breeders hope to combine the best of the populations to create varieties best suited for particular locations.On a fundamental level, the study will help scientists tease out answers to basic questions about plant biology, such as the circuits involved in the rhizome nutrient cycle, how it works through the seasons, and how it evolved. And it will give them more information about the rules for crossing and combining miscanthus so they can produce optimal hybrids, Rokhsar said."The types of data presented in this study are also critical to deploy techniques like gene-editing to help decipher the function of the genes that control traits and adaptations important to the success of this high-yielding grass," Swaminathan said.For example, the gene expression data point to a suite of genes that may be involved in the ability of miscanthus to store energy in a modified underground stem (the rhizome) over winter and bounce back each year bigger than before. Swaminathan is intrigued by what makes a stem become a storage organ in Andropogoneae grasses; she wants to understand the molecular mechanisms that direct the miscanthus rhizome to store complex carbohydrates while sugarcane and sweet sorghum stems store sugar.Miscanthus and other plants have complex genomes, with a history of more genomic duplication than seen in animals. Having multiple copies of chromosomes allows for larger plants and more genetic diversity while providing more targets for genetic engineers. But it also made the sequencing and assembly a challenge, Rokhsar said. "We drew on lots of different technologies to make that happen."The team's analysis determined that miscanthus is a "paleo-allotetraploid," meaning it arose by ancient hybridization of two ancestral species, rather than by doubling within a single species as happened in sugarcane. The two progenitors of miscanthus are long-extinct -- dying out after the hybridization about 2 million years ago -- but their chromosomes live on in miscanthus. Session used computational analyses to figure out the ancient origins of each chromosome and identify segments that have swapped chromosomes. He also teased apart subtle differences in the way the two chromosome sets have evolved since the duplication -- vital information for genetic engineers who want to knock out particular genes, Mitros said.The paper is the culmination of a multi-year, interdisciplinary effort to sequence a miscanthus genome involving dozens of researchers in the U.S., Europe, and Asia. It is built on the work of scientists like Sacks, who has collected germplasm from thousands of lines of Miscanthus in Japan, Korea, and other countries.Other instrumental researchers included Professors Stephen Moose and Matthew Hudson, University of Illinois crop scientists who were involved in the genome project when the project was under the auspices of the Energy Biosciences Institute, a BP-funded initiative at Illinois, UC Berkeley and Berkeley Lab. Professor Stephen Long, another U of I crop scientist, had been among the first to propose miscanthus as the basis for a new biofuel economy as part of a scientific team in the College of Agricultural, Consumer and Environmental Sciences. Moose led EBI's feedstocks group and pioneered the genomics work, producing chromosome maps of M. sinensis and early gene expression data sets for multiple Miscanthus lines. The JGI carried out much of the genome sequencing under the supervision of Rokhsar, who was also part of the original EBI project and has a long-standing interest in complex plant and animal genomes.Swaminathan was a scientist on Moose's team during the EBI project. The team, which included Rokhsar and Mitros, started by trying to decipher the M. x giganteus Illinois genome, but "it was a jigsaw puzzle not coming together," she said. The researchers realized that M. x giganteus was too complicated, and turned to a double-haploid line of M. sinensis generated by Katarzyna Glowacka, then a graduate student in Poland and now a faculty member at the University of Nebraska. Using the best available data at the time, they put together a fragmented genome assembly. Swaminathan joined HudsonAlpha in 2016, bringing a freezer full of samples with her, and both James and fellow Postdoc Mohammad Belaffif started processing samples and analyzing the data.CABBI was formed in 2017 and took on the genome project. Mitros pulled together the genomic analysis. Swaminathan's team focused on gene expression, and Sacks contributed data from his diversity collections. Researchers in Europe shared genotype data and information on the M. sacchariflorus genome, and the project grew."It took that concerted effort, with someone at the center pulling all the data together to make sense of it," Swaminathan said. "This would have just not happened without CABBI."
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Agriculture & Food
| 2,020 |
October 29, 2020
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https://www.sciencedaily.com/releases/2020/10/201029104951.htm
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Black soldier fly larvae as protein alternative for hungry humans
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It may seem a little hard to swallow but the larvae of a waste-eating fly could become a new alternative protein source for humans, according to a University of Queensland scientist.
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Professor Louw Hoffman said black soldier fly's larvae, which was already utilised for animal feed, was a high quality protein."Just like meat, it contains all the nutrients humans need for health," Professor Hoffman said."The larvae is richer in zinc and iron than lean meat, and its calcium content is as high as that of milk.""Their nutritional composition makes them an interesting contender as a meat alternative, and to date they have demonstrated their potential to partially replace meat in burger patties and Vienna sausages."Professor Hoffman said the United Nation's Food and Agriculture Organization estimated that two billion people around the world already ate insects regularly as part of their diet."The biggest factor that prevents fly proteins being used in our food supply is Western consumer's' acceptance of insects as food," he said."We will eat pea or oat milk, even lab-grown meats, but insects just aren't on Western menus."Professor Hoffman has been studying the hurdles that need to be overcome before flies can directly enter the human food supply chain."There's a lot of research that's already been done on black soldier fly larvae as a feed for livestock, but we need to ensure we address safety issues before it can get legs as a human food," he said."This includes understanding the different nutritional profiles of the fly at key stages of its growth, and the best ways to process the fly to preserve its nutritional value."While the fly can clean up toxic waste including heavy metals, it's also recommended flies bred for human food be fed a clean source of organic waste."In addition to its nutrition profile, Professor Hoffman said there were strong environmental reasons for humans to eat fly larvae.It's estimated that less than half a hectare of black soldier fly larvae can produce more protein than cattle grazing on around 1200 hectares of cattle, or 52 hectares of soybeans."If you care about the environment, then you should consider and be willing to eat insect protein," he said.
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Agriculture & Food
| 2,020 |
October 28, 2020
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https://www.sciencedaily.com/releases/2020/10/201028134025.htm
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Researchers map genomes of agricultural 'monsters'
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The University of Cincinnati is decoding the genetics of agricultural pests in projects that could help boost crop and livestock production to feed millions more people around the world.
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Joshua Benoit, an associate professor in UC's College of Arts and Sciences, contributed to genetic studies of New World screwworms that feed on livestock and thrips, tiny insects that can transmit viruses to tomatoes and other plants.It's the latest international collaboration for Benoit, who previously sequenced the DNA for genomes of dreaded creatures such as bedbugs.Just in time for Halloween, Benoit's new study subject is no less creepy. The New World screwworm's Latin name means "man-eater." These shiny blue flies with pumpkin-orange eyes lay up to 400 eggs in open cuts or sores of cattle, goats, deer and other mammals. Emerging larvae begin gnawing away on their hosts, feeding on living and dead tissue and creating ghastly wounds."Sometimes you'll see a deer missing a chunk of its head. The flies can cause small wounds to become massive injuries," he said.Benoit and his co-authors sequenced the genome of screwworms and identified ways of slashing populations by targeting particular genes that determine sex and control growth and development or even particular behaviors that help the flies find a suitable animal host.The study led by entomologist Maxwell Scott at North Carolina State University was published in the journal "Our main goal was to use the genomic information to build strains that produce only males for an enhanced sterile-insect program," Scott said.The New World screwworm is an agricultural menace that causes billions of dollars in livestock losses each year in South America, where it is common. The fly was a scourge in North America as well but was eradicated from the United States in 1982 with intense and ongoing population controls.Today, a lab operated by Panama and the U.S. Department of Agriculture has established a biological barrier outside Panama City, a geographic choke point between the two continents."They rear flies in a lab, sterilize them with chemicals or radiation and dump these sterile male flies into the environment from a plane so they mate with the females and produce no offspring," Benoit said.Year by year, agriculture experts gradually pushed the screwworm out of Texas, Mexico and most of Central America."They just used straight brute force and good science ," Benoit said. "They just drove them down all the way to Panama."Today, Panama and the United States continue to air-drop sterile screwworms by the millions each week over the choke point to prevent the species from moving north.A 2016 outbreak in the Florida Keys threatened to wipe out endangered Key deer before the USDA intervened, treating infected animals with a parasite medicine and releasing millions of sterile screwworms on the island chain until they disappeared."The U.S. still helps pay for control programs in Panama mainly because we don't want screwworms coming back here. It's the cheapest way to prevent potentially billions of dollars in damage," Benoit said.One possible way to cut costs would be to raise only male screwworms that are intended for release so the lab wouldn't incur the huge costs of feeding female screwworms. UC's genetic study could help scientists cull females before they hatch."So you're left with surviving males. Then you sterilize the males and that would save a lot of money because you'd only have to raise the males for release," he said.Next, Scott said he wants to understand how the livestock-devouring screwworm Cochliomyia hominivorax evolved as a parasitic meat eater while similar species prefer carrion.Benoit also contributed to a genomic study in the journal In a study led by entomologist Dorith Rotenberg at North Carolina State University, researchers mapped 16,859 genes that helped understand the thrips' sensory and immune systems and the salivary glands that transmit the viruses."The genome provides the essential tools and knowledge for developing genetic pest management strategies for suppressing thrips pest populations," Rotenberg said.One thrips virus is a particular agricultural concern: the spotted wilt virus, which studies have found can reduce a crop's yield by as much as 96%."We're talking hundreds of millions of dollars in losses," Benoit said.The study found that thrips can be finicky eaters and have unique genetic adaptations that likely allows them to feed on many insects. They pierce the plant and suck the juices.And thrips have surprisingly sophisticated immune systems, the study found. Researchers identified 96 immune genes, more than many other insects studied to date."We mapped the genome, but we also characterized immune aspects and how they feed," Benoit said. "It was the first study of its kind to explain what underlies their reproductive mechanisms. It was far more detailed than previous genomic studies we've done."The study was funded in part by the National Science Foundation and a UC faculty development research grant.Benoit said the solution to a thrips infestation predictably has been pesticides. But the UC study could help find better environmental solutions, he said."Pesticides do not discriminate at all. The same pesticide that kills a termite can kill a bee. When you spray, it can kill other beneficial insects," Benoit said. "So we don't want to eradicate species as much as find better ways to control them so we don't have to use as much pesticide."
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Agriculture & Food
| 2,020 |
October 27, 2020
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https://www.sciencedaily.com/releases/2020/10/201027105405.htm
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Geologists simulate soil conditions to help grow plants on Mars
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Humankind's next giant step may be onto Mars. But before those missions can begin, scientists need to make scores of breakthrough advances, including learning how to grow crops on the red planet.
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Practically speaking, astronauts cannot haul an endless supply of topsoil through space. So University of Georgia geologists are figuring out how best to use the materials already on the planet's surface.To do that, they developed artificial soil mixtures that mimic materials found on Mars. In a new study published in the journal Icarus, the researchers evaluated the artificial soils to determine just how fertile Martian soil could be."We want to simulate certain characteristics of materials you could easily get on Mars' surface," said Laura Fackrell, UGA geology doctoral candidate and lead author on the study. Simulating the mineral makeup or salt content of these Martian mixtures can tell us a lot about the potential fertility of the soil. Things like nutrients, salinity, pH are part of what make a soil fertile and understanding where Mars' soils are at in that spectrum is key to knowing if they are viable and if not, are there feasible solutions that can be used to make them viable."In the last decade, Martian surface exploration has expanded the understanding of the chemistry of the planet's surface. Using data taken from NASA's surface samples, the team studied regolith, or the loose material near the surface, to develop the simulants.The materials used mimic mixtures of soil, clay minerals, salts and other materials obtainable from Mars' surface by scooping loose material or mining it from bedrock.Despite its thin atmosphere, extreme cold and low oxygen, Mars' surface is known to contain the majority of plant essential nutrients, including nitrogen, phosphorus and potassium.The presence of nutrients accomplishes one of the big hurdles, but there are still more challenges. "One problem is, their presence doesn't mean they are accessible to plants," Fackrell said. "If you actually put a plant in the ground -- just because the iron or the magnesium is there doesn't mean the plant can actually pull it out of the soil."Plus, the nutrients may or may not be present in sufficient quantity or they may be so high in concentration that they are toxic to plants.Using simulated Martian soils, Fackrell and fellow researchers have found the textures of artificial simulants to be crusty and dried which may reflect some unexpected conditions of Mars soils that make them more difficult to use.These challenges add up to a very difficult, though not impossible task. Looking to agricultural science, the group, which includes UGA faculty members Paul Schroeder, Mussie Habteselassie and Aaron Thompson, adapts solutions used on Earth, recommendations that range from rinsing the soil to adding inoculants like bacteria or other fungi to the soil to help the plants grow."Specific types of bacteria and fungi are known to be beneficial for plants, and may be able to support them under stress conditions like we see on Mars," said Fackrell, who began her studies in geomicrobiology with Schroeder while conducting her master's thesis research on extreme environments faced by microbes living in hot springs in the Kamchatka Peninsula, in the Russian Far East.The scientists also see implications from their research for potential innovations in agricultural research for Earth. "Anything we learn about farming on Mars could help with farming in challenging environments on Earth that help us build to a sustainable future," Fackrell said.Whatever the eventual solution, the prospect of a manned mission to Mars hinges on the ability to grow food."There are multiple ways you can look at it, but one option might be to use what's already there as a potting medium, and figure out if that's a viable way to do it or if you have to bring all the plant materials with you," Fackrell said. "The question of whether we can use Mars soil to provide that food will go a long way toward determining the feasibility of manned missions."
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Agriculture & Food
| 2,020 |
October 26, 2020
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https://www.sciencedaily.com/releases/2020/10/201026184005.htm
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Common liverwort study has implications for crop manipulation
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A new study on genetic pathways in the common liverwort could have future implications for crop manipulation.
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The findings of the US-led study, co-authored by genetic biologist Professor John Bowman from the Monash University School of Biological Sciences, are published today in Earlier this year researchers confirmed a new role for the well-known plant molecule known as 1-aminocyclopropane-1-carboxylic acid (ACC), providing the first clear example of it acting on its own as a likely plant hormone.ACC is the precursor of the plant hormone ethylene which has many roles in growth and development."Ethylene was the first gaseous hormone identified over 100 years ago in flowering plants," explains Professor Bowman."It is the 'ripening hormone', that is, the one bad apple spoils the lot," he said."The ethylene signalling pathway has been characterised in flowering plants, and its disruption results in a number of defects, including fruit ripening.However, land plants evolved from an aquatic alga, and genes encoding the ethylene signalling pathway can be found in extant algae, and were likely acquired from the cyanobacterial endosymbiont that evolved into the chloroplast, suggesting the pathway long predated the evolution of fruit ripening."Being able to understand and control ethylene production has major implications for agriculture and horticulture."Professor Bowman and collaborators investigated the ethylene signalling pathway in the liverwort Marchantia, and showed that while ethylene acted as a signalling molecule similar to the situation in flowering plants, the enzymatic precursor to ethylene in flowering plants, ACC, was a biologically active molecule as well."As liverworts do not make ethylene via ACC, it suggests that ACC was a biologically active molecule in the ancestral land plant, and that the ethylene pathway as we know it in flowering plants evolved via co-option of pre-existing pathways," Professor Bowman said."These pathways likely still exist in flowering plants and may be able to be manipulated to affect ethylene signalling, and its incumbent biological processes in crop plants," he said.
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Agriculture & Food
| 2,020 |
October 26, 2020
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https://www.sciencedaily.com/releases/2020/10/201026114200.htm
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A molecular break for root growth
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Roots are essential for reaching water and nutrients, for anchorage to the ground, but also for interacting and communicating with microorganisms in the soil. A long root enables the plant to reach deeper, more humid layers of soil, for example during drought. A shallower root with many root hairs is good for phosphate uptake, as phosphate is mostly found in the upper soil layers.
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Caroline Gutjahr, Professor of Plant Genetics at the TUM School of Life Sciences in Weihenstephan, and her team discovered new hormone interactions which influence the growth of plant roots."We found that the protein SMAX1 acts as molecular break for ethylene production," says Caroline Gutjahr. Ethylene is a plant hormone that is considered to trigger or accelerate the ripening of many fruits and vegetables, but it can also trigger other processes in plants. If less of the gaseous hormone is produced by the plant, the plant is stimulated to grow long roots and short root hairs.The suppressor "SMAX1" can be removed by activating the so-called karrikin signaling pathway, which is triggered by another hormone. This switches on the production of ethylene, resulting in short primary roots and elongated root hairs.This is the first time that scientists have succeeded in identifying and understanding a molecular process that is switched on by the karrikin signaling pathway and in showing a molecular mechanism, by which this signaling pathway regulates a developmental process in plants.Plant diversity is also reflected in molecular mechanisms"Surprisingly this mechanism has a significant impact on the roots of the legume Lotus japonicus, the model plant for peas, beans and lentils, on which we conducted our research," says Gutjahr.In contrast, the research team observed a much weaker influence in the roots of another model plant, Arabidopsis thaliana or thale cress, which is related to cabbage plants."This shows that the diversity of plants is not only reflected in their appearance, but also in the effect of their molecular triggers on growth," the researcher concludes."If we understand more precisely how root growth is regulated at the molecular level and in coordination with environmental stimuli, we can cultivate crops that are better able to cope with unfavorable environmental conditions and thus produce yield even under stress," explains the scientist.This is why her research group is now investigating how the identified hormone signaling pathways (karrikin and ethylene signaling) react to different environmental conditions. They hope to discover how these two signaling pathways collaborate with the sensors that allow plants to perceive various environmental influences to adjust root growth to benefit plant survival and yield.
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Agriculture & Food
| 2,020 |
October 22, 2020
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https://www.sciencedaily.com/releases/2020/10/201022083303.htm
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Grafting with epigenetically-modified rootstock yields surprise
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Novel grafted plants -- consisting of rootstock epigenetically modified to "believe" it has been under stress -- joined to an unmodified scion, or above-ground shoot, give rise to progeny that are more vigorous, productive and resilient than the parental plants.
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That is the surprising finding of a team of researchers that conducted large-scale field trials with tomato plants at three widely separated locations over multiple plant generations. They contend that the discovery, which came from a collaboration between Penn State, the University of Florida and a small start-up company in Nebraska, has major implications for plant breeding.Because the technique involves epigenetics -- manipulating the expression of existing genes and not the introduction of new genetic material from another plant -- crops bred using this technology could sidestep controversy associated with genetically modified organisms and food. That is the hope of research team leader Sally Mackenzie, professor of plant science in the College of Agricultural Sciences and professor of biology in the Eberly College of Science at Penn State."Although we did this with tomato, it can be done with any plant," she said. "We think that this study represents a major breakthrough in showing the potential of epigenetic breeding for crops. And later, it will have major implications for trees and forests in the face of climate change."Building on previous research conducted by Mackenzie's research group at Penn State, the rootstock came from tomato plants in which researchers manipulated the expression of a gene called MSH1 to induce the "stress memory." That memory is inherited by some progeny, giving them the potential for more vigorous, hardy and productive growth.The MSH1 gene gave researchers access to the pathway controlling a broad array of plant resiliency networks, explained Mackenzie, who is the Lloyd and Dottie Huck Chair for Functional Genomics and director of the Plant Institute at Penn State. "When a plant experiences a stress such as drought or prolonged extreme heat, it has the ability to adjust quickly to its environment to become phenotypically 'plastic' -- or flexible," she said. "And, it turns out, it 'remembers.'"The finding that those "remembered" traits passed from the roots through the graft to the top of the plant -- published today (Oct. 22) in The plants are hardier, too, according to Mackenzie. During a component of the study at Penn State's Russell E. Larson Agricultural Research Center in 2018, storms dropped more than 7 inches of rain in August, flooding the tomato fields. The pooled water wiped out plants that were part of other research trials. However, the plants that were the offspring of the grafted plants with the epigenetically manipulated rootstock mostly survived -- and then they thrived.The progeny of the grafted plants also showed superior survivability in the other field trials conducted in California and Florida.The research is the first true demonstration of an agriculturally amenable epigenetic breeding method, Mackenzie said, adding that the technology is ready to deploy immediately."Everything we're doing, any plant breeder in agriculture can do, and now we've shown on a large scale that it has agricultural value. It's ready to go -- a breeder could read about this and implement the system to improve his or her variety," said Mackenzie.Also involved in the research at Penn State were: Michael Axtell, professor of biology; Xiaodong Yang, assistant research professor of biology; Robersy Sanchez, associate research professor of biology; and Hardik Kundariya, graduate student in biology; Samuel Hutton, University of Florida; and Michael Fromm and Kyla Morton, EpiCrop Technologies, Lincoln, Nebraska.The work was supported by funding from the National Science Foundation, the National Institutes of Health and the U.S. Department of Agriculture's National Institute of Food and Agriculture.
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Agriculture & Food
| 2,020 |
October 20, 2020
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https://www.sciencedaily.com/releases/2020/10/201020105524.htm
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Plants communicate at a molecular level
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Working together with researchers from the University of Tübingen, the University of Tromsø, the UC Davis and the Sainsbury Laboratory in Norwich, biologists from FAU have discovered how tomato plants identify Cuscuta as a parasite. The plant has a protein in its cell walls that is identified as 'foreign' by a receptor in the tomato.
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Cuscuta spp., also known as dodder, is a parasitic vine which grafts to the host plant using special suckers to obtain water, minerals and carbohydrates. The parasite also attacks and damages crops such as oilseed rape, sweetcorn, soy, flax or clover. Although the infection generally goes undetected by the host, some species of tomato actively defend themselves by forming wooden tissue which prevents the suckers from penetrating the plant. In earlier research, the biologists at FAU discovered that these tomatoes possess a special receptor, the Cuscuta receptor 1 (CuRe1), which triggers the defence mechanism. However, until now it was unclear how the receptor recognises the danger posed by the dodder.The researchers have now succeeded in answering this question: the dodder possesses a specific marker in its cellular wall, a glycine-rich protein (GRP). Using its receptor CuRe1, the tomato is able to recognise the molecular pattern of the GRP and identify the dodder as a pathogen, and triggers the immune reaction as a result. The new findings concerning the molecular dialogue between the Cuscuta marker and the tomato receptor may help to increase the resistance of crop plants against parasitic plants.
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Agriculture & Food
| 2,020 |
October 19, 2020
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https://www.sciencedaily.com/releases/2020/10/201019145551.htm
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Cheaters don't always win: Species that work together do better
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The sign of a healthy personal relationship is one that is equally mutual -- where you get out just as much as you put in. Nature has its own version of a healthy relationship. Known as mutualisms, they are interactions between species that are mutually beneficial for each species. One example is the interaction between plants and pollinators, where your apple trees are pollinated and the honeybee gets nectar as a food reward. But what makes these mutualisms persist in nature? If rewards like nectar are offered freely, does this make mutualisms more susceptible to other organisms that take those rewards without providing a service in return?
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A team of researchers from the College of Arts and Sciences at Syracuse University, including co-principal investigators Kari Segraves, professor of biology, and David Althoff, associate professor of biology, along with postdoctoral researcher Mayra Vidal, former research assistant professor David Rivers, and Sheng Wang '20 Ph.D., recently researched that question and the results have been published in this month's edition of the prestigious journal They investigated the abilities of simple versus diverse communities of mutualists, comparing how each deal with cheaters. Cheaters are species that steal the benefits of the mutualism without providing anything in return. An example of one of nature's cheaters are nectar robbers. Nectar-robbing bees chew through the side of flowers to feed on nectar without coming into contact with the flower parts that would result in pollination.The research team wanted to test if having multiple mutualists with similar roles allows the community as a whole to persist when cheaters take away the mutualists' resources. The idea was to examine whether having more species involved in a mutualism, such as many pollinator species interacting with many different plant species, made the mutualism less susceptible to the negative effects of cheaters. They also wanted to analyze whether increasing the number of mutualist species allowed all the mutualists to persist or if competition would whittle down the number of mutualists species over time. In essence, the team wanted to understand the forces governing large networks of mutualists that occur in nature.A&S researchers tested their ideas by producing mutualisms in the lab using yeast strains that function as mutualistic species. These strains were genetically engineered to trade essential food resources. Each strain produced a food resource to exchange with a mutualist partner. They engineered four species of each type of mutualist as well as two cheater strains that were unable to make food resources.The researchers assembled communities of yeast that differed both in the number of species and the presence of cheaters. They found that communities with higher numbers of mutualist species were better able to withstand the negative effects of cheaters because there were multiple species of mutualists performing the same task. If one species was lost from the community due to competing with a cheater, there were other species around to perform the task, showing that the presence of more species in a community can lessen the negative effects of cheaters."It's similar to thinking about a plant that has many pollinator species," says Segraves. "If one pollinator species is lost, there are other pollinator species around to pollinate. If a plant only has one species of pollinator that goes extinct, the mutualism breaks down and might cause extinction of the plant."Their results highlight the importance of having multiple mutualist species that provide similar resources or services, essentially creating a backup in case one species goes extinct. Segraves compares this phenomenon to the relationship between retailers and consumers. Communities typically have multiple banks, grocery stores, restaurants and hospitals to ensure that there are always goods and services available should something happen to one company or facility, or, as with COVID today, grocery stores now have multiple suppliers to fend off shortages.Segraves says future research will explore the possibility of a mutualist species becoming a cheater. The group is testing if mutualists that perform the same function might set up an environment that allows one of those mutualist species to become a cheater since there are other mutualists around that can fill that role. They predict that the mutualist species that is experiencing the most competition from the other mutualists will be the species that switches to cheating. They also hope to determine how the mutualists and cheaters evolved over time to provide a deeper understanding of the actual changes that led to differing outcomes in the communities.The team's research was funded by a $710,000, three-year grant from the National Science Foundation.
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Agriculture & Food
| 2,020 |
October 19, 2020
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https://www.sciencedaily.com/releases/2020/10/201019125519.htm
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Biochar helps hold water, saves money
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The abstract benefits of biochar for long-term storage of carbon and nitrogen on American farms are clear, and now new research from Rice University shows a short-term, concrete bonus for farmers as well.
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That would be money. To be precise, money not spent on irrigation.In the best-case scenarios for some regions, extensive use of biochar could save farmers a little more than 50% of the water they now use to grow crops. That represents a significant immediate savings to go with the established environmental benefits of biochar.The open-access study appears in the journal Biochar is basically charcoal produced through pyrolysis, the high-temperature decomposition of biomass, including straw, wood, shells, grass and other materials. It has been the subject of extensive study at Rice and elsewhere as the agriculture industry seeks ways to enhance productivity, sequester carbon and preserve soil.The new model built by Rice researchers explores a different benefit, using less water."There's a lot of biochar research that focuses mostly on its carbon benefits, but there's fairly little on how it could help stakeholders on a more commercial level," said lead author and Rice alumna Jennifer Kroeger, now a fellow at the Science and Technology Policy Institute in Washington, D.C. "It's still an emerging field."The study co-led by Rice biogeochemist Caroline Masiello and economist Kenneth Medlock provides formulas to help farmers estimate irrigation cost savings from increased water-holding capacity (WHC) with biochar amendment.The researchers used their formulas to reveal that regions of the country with sandy soils would see the most benefit, and thus the most potential irrigation savings, with biochar amendment, areas primarily in the southeast, far north, northeast and western United States.The study analyzes the relationship between biochar properties, application rates and changes in WHC for various soils detailed in 16 existing studies to judge their ability to curtail irrigation.The researchers defined WHC as the amount of water that remains after allowing saturated soil to drain for a set period, typically 30 minutes. Clay soils have a higher WHC than sandy soils, but sandy soils combined with biochar open more pore space for water, making them more efficient.WHC is also determined by pore space in the biochar particles themselves, with the best results from grassy feedstocks, according to their analysis.In one comprehensively studied plot of sandy soil operated by the University of Nebraska-Lincoln's Agricultural Water Management Network, Kroeger calculated a specific water savings of 37.9% for soil amended with biochar. Her figures included average rainfall and irrigation levels for the summer of 2019.The researchers noted that lab experiments typically pack more biochar into a soil sample than would be used in the field, so farmers' results may vary. But they hope their formula will be a worthy guide to those looking to structure future research or maximize their use of biochar.More comprehensive data for clay soils, along with better characterization of a range of biochar types, will help the researchers build models for use in other parts of the country, they wrote."This study draws attention to the value of biochar amendment especially in sandy soils, but it's important to note that the reason we are calling out sandy soils here is because of a lack of data on finer-textured soils," Masiello said. "It's possible that there are also significant financial benefits on other soil types as well; the data just weren't available to constrain our model under those conditions.""Nature-based solutions are gaining traction at federal, state and international levels," Medlock added, noting the recently introduced Growing Climate Solutions Act as one example. "Biochar soil amendment can enhance soil carbon sequestration while providing significant co-benefits, such as nitrogen remediation, improved water retention and higher agricultural productivity. The suite of potential benefits raises the attractiveness for commercial action in the agriculture sector as well as supportive policy frameworks."
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Agriculture & Food
| 2,020 |
October 19, 2020
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https://www.sciencedaily.com/releases/2020/10/201019111915.htm
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High social and ecological standards for chocolate
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Worldwide demand for food from the tropics that meets higher environmental and social standards has risen sharply in recent years. Consumers often have to make ethically questionable decisions: products may be available to the global market through child labour, starvation wages or environmental destruction. Building on an interdisciplinary project in Peru, an international research team with the participation of the University of Göttingen has now published an overview article on the transition to responsible, high-quality cocoa production. Chocolate is made from cocoa beans, and because cocoa is originally from Peru, using indigenous varieties means a premium price can be charged. A large cooperative for small-holder farmers in northern Peru stands for social and ecological improvements with the help of organic and fair-trade certification, as well as the cultivation of native varieties in species-rich cocoa agroforestry systems. The work was published as a "Perspective" article in the journal
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Shade trees in traditional cocoa agroforestry systems improve conditions for cocoa growth and promote biodiversity, for instance of birds. However, these trees are increasingly being removed to increase productivity, even though moderate, partial shade does not significantly reduce productivity. In addition, proven high-yielding varieties are imported, although there are unique indigenous varieties in Peru that may be associated with a particular trade advantage. The researchers' project group is working together with the cooperative Norandino Ltda. in Piura, northern Peru, which is committed to working towards developing high social and ecological standards. It represents 5,400 smallholder farmers and stands for sustainable production that pursues both ecological and economic goals. Furthermore, the cooperative is committed to fighting all forms of discrimination. The result is ecologically certified and fair-trade chocolate of a high standard, which achieves up to twice the regular market price, protects smallholder farmers against market fluctuations and moves towards the greater use of local cocoa bean varieties in the future.Dr Bea Maas, first author of the article and now at the University of Vienna, emphasises: "Large cooperatives that stand for high social, economic and ecological standards in production should receive more support." Carolina Ocampo-Ariza and Professor Teja Tscharntke from the Agroecology group at the University of Göttingen add: "Such exemplary initiatives that benefit the livelihoods of smallholder farmers while maximising nature conservation should be the focus of interdisciplinary research now more than ever before."
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Agriculture & Food
| 2,020 |
October 16, 2020
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https://www.sciencedaily.com/releases/2020/10/201016090157.htm
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During COVID, scientists turn to computers to understand C4 photosynthesis
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When COVID closed down their lab in March, a team from the University of Essex turned to computational approaches to understand what makes some plants better adapted to transform light and carbon dioxide into yield through photosynthesis. They published their findings in the journal
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There are two kinds of photosynthesis: C3 and C4. Most food crops depend on C3 photosynthesis where carbon is fixed into sugar inside cells called 'mesophyll' where oxygen is abundant. However, oxygen can hamper photosynthesis. C4 crops evolved specialized bundle sheath cells to concentrate carbon dioxide, which makes C4 photosynthesis as much as 60 percent more efficient.In this study, scientists wanted to find out how C4 crops are able to express several important enzymes inside bundle sheath cells instead of the mesophyll."The ultimate goal is to be able to understand these mechanisms so that we can improve C3 photosynthesis in food crops like cowpea and cassava that smallholder farmers in sub-Saharan Africa depend on for their families' food and income," said Chidi Afamefule, a postdoctoral researcher working on Realizing Increased Photosynthetic Efficiency (RIPE) at Essex.Led by the University of Illinois at the Carl R. Woese Institute for Genomic Biology, RIPE aims to boost food production by improving photosynthesis with support from the Bill & Melinda Gates Foundation, Foundation for Food and Agriculture Research, and U.K. Foreign, Commonwealth & Development Office. The RIPE project and its sponsors are committed to ensuring Global Access and making the project's technologies available to the farmers who need them the most.The team compared the DNA of four C3 grass crops (including barley and rice) and four C4 grass crops (including corn and sorghum). Their goal was to identify regions of DNA that might control the expression of four enzymes involved in photosynthesis. This study is likely the first comparison of the expression of these enzymes (SBPase, FBPase, PRK, and GAPDH) in C3 and C4 crops."It would have been great to find a 'master regulator' that operates in all these enzymes, but we didn't find it, and we suspect it doesn't exist," said Afamefule, who led the study from his apartment during the pandemic.Instead, they discovered C4 crops have several "activators" within their DNA that trigger expression in the bundle sheath and "repressors" that restrict expression in the mesophyll. They hope that they can use this genetic code to help less-efficient C3 crops photosynthesize better in the future."There are already efforts underway to help C3 crops operate more like C4 crops," said principal investigator Christine Raines, a professor in the School of Life Sciences at Essex where she also serves as the Pro-Vice-Chancellor for Research. "Studies like this help us identify small pieces within an incredibly complex machine that we have to understand before we can fine-tune and reengineer it."The next step is to validate these findings in the lab. The team returned to their lab benches on July 6, 2020, adhering to all recommended safety guidelines from the School of Life Sciences at Essex.Realizing Increased Photosynthetic Efficiency (RIPE) aims to improve photosynthesis and equip farmers worldwide with higher-yielding crops to ensure everyone has enough food to lead a healthy, productive life. RIPE is sponsored by the Bill & Melinda Gates Foundation, the U.S. Foundation for Food and Agriculture Research, and the U.K. Foreign, Commonwealth & Development Office.RIPE is led by the University of Illinois in partnership with The Australian National University, Chinese Academy of Sciences, Commonwealth Scientific and Industrial Research Organisation, Lancaster University, Louisiana State University, University of California, Berkeley, University of Cambridge, University of Essex, and U.S. Department of Agriculture, Agricultural Research Service.
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Agriculture & Food
| 2,020 |
October 16, 2020
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https://www.sciencedaily.com/releases/2020/10/201016090222.htm
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Plant genetic engineering to fight 'hidden hunger'
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More than two billion people worldwide suffer from micronutrient malnutrition due to deficiencies in minerals and vitamins. Poor people in developing countries are most affected, as their diets are typically dominated by starchy staple foods, which are inexpensive sources of calories but contain low amounts of micronutrients. In a new Perspective article, an international team of scientists, involving the University of Göttingen, explains how plant genetic engineering can help to sustainably address micronutrient malnutrition. The article was published in
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Micronutrient malnutrition leads to severe health problems. For instance, vitamin A and zinc deficiency are leading risk factors for child mortality. Iron and folate deficiency contribute to anemia and physical and cognitive development problems. Often, the people affected are not aware of their nutritional deficiencies, which is why the term 'hidden hunger' is also used. The long-term goal is that all people are aware of healthy nutrition and have sufficient income to afford a balanced diet all year round. However, more targeted interventions are required in the short and medium term.One intervention is to breed staple food crops for higher micronutrient contents, also known as 'biofortification'. Over the last 20 years, international agricultural research centres have developed biofortified crops using conventional breeding methods, including sweet potato and maize with vitamin A, as well as wheat and rice with higher zinc content. These crops were successfully released in various developing countries with proven nutrition and health benefits. However, conventional breeding approaches have certain limitations.In the Perspective article, the scientists report how genetic engineering can help to further enhance the benefits of biofortified crops. "Transgenic approaches allow us to achieve much higher micronutrient levels in crops than conventional methods alone, thus increasing the nutritional efficacy. We demonstrated this for folates in rice and potatoes," says Professor Dominique Van Der Straeten from Ghent University, the article's lead author. "We also managed to reduce post-harvest vitamin losses significantly," she adds.Another advantage of genetic engineering is that high amounts of several micronutrients can be combined in the same crop. "This is very important, as poor people often suffer from multiple micronutrient deficiencies," says co-lead author and 2016 World Food Prize Laureate Dr Howarth Bouis from the International Food Policy Research Institute.Genetic engineering can also help to combine micronutrient traits with productivity-enhancing agronomic traits, such as drought tolerance and pest resistance, which are becoming ever more relevant with climate change. "Farmers should not have to make difficult choices between crops that either improve nutrition or allow productive and stable harvests. They need both aspects combined, which will also support widespread adoption," says co-author Professor Matin Qaim from the University of Göttingen.The authors acknowledge that genetic engineering is viewed skeptically by many, despite the fact that the resulting crops have been shown to be safe for human consumption and the environment. One of the reasons for the public's reservations is that genetic engineering is often associated with large multinational companies. "Biofortified crops may possibly reduce some of the concerns, as these crops are developed for humanitarian purposes," state the authors. "Public funding is key to broader acceptance."
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Agriculture & Food
| 2,020 |
October 14, 2020
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https://www.sciencedaily.com/releases/2020/10/201014141145.htm
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'Honey bee, it's me'
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For a honey bee, few things are more important than recognizing your nestmates. Being able to tell a nestmate from an invader could mean the difference between a honey-stocked hive and a long, lean winter.
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New research from Washington University in St. Louis shows that honey bees rely on chemical cues related to their shared gut microbial communities, instead of genetic relatedness, to identify members of their colony."Most people only pay attention to the genetics of the actual bee," said Yehuda Ben-Shahar, professor of biology in Arts & Sciences and corresponding author of the study published Oct. 14 in Honey bees recognize and respond to chemical signals from other bees that they detect from skin compounds known as cuticular hydrocarbons, or CHCs. This study determined that a bee's particular CHC profile is dependent on its microbiome -- the bacteria that make up its gut microbial community -- and is not something innate or genetic to the bee alone."Different colonies do in fact have colony-specific microbiomes, which has never been shown before," said Cassondra L. Vernier, postdoctoral associate at the University of Illinois, who earned her biology PhD working with Ben-Shahar at Washington University."Bees are constantly sharing food with one another -- and exchanging this microbiome just within their colony," said Vernier, first author of the new study.Co-authors include Gautam Dantas, professor of pathology and immunology and of molecular microbiology at Washington University School of Medicine in St. Louis, and Joel Levine at the University of Toronto Mississauga. The work was conducted in part with bees housed at Tyson Research Center, the environmental field station for Washington University."The importance of this paper is that it's one of the first papers that actually shows that the microbiome is involved in the basic social biology of honey bees -- and not just affecting their health," Vernier said. "The microbiome is involved in how the colony as a whole functions, and how they are able to maintain nest defenses, rather than just immune defense within an individual."The gut microbial community -- or microbiome -- supplies humans and other animals with vitamins, helps digest food, regulates inflammation and keeps disease-causing microbes in check. Increasingly a topic of research interest, scientists have discovered many ways that the microbiome blurs the borders between a host and its bacteria.The microbiome has been found to influence communication in several different organisms -- including, notably, large animals like hyenas.For honey bees, this study shows that the microbiome plays a critical role in defining the tightly regulated chemical signals for group membership.Until recently, most scientists thought that honey bees identified nestmates by picking up on a homogenized scent that they recognize from members of their own colony -- "a kind of hive B.O.," Ben-Shahar joked.Bee colonies are usually composed of highly related individuals. But the chemical signals that allow bees to recognize each other are not determined by genetics alone. Researchers know this because baby bees can be placed into other colonies without being rejected -- up until a certain age and level of development."It has to be something that they acquire during their lifetime that defines their nestmate recognition cues," Vernier said.In previous work, Vernier and Ben-Shahar showed that bees develop different scent profiles as they age, and that gatekeeper bees respond differently to foragers returning to the hive compared with younger bees that have never ventured outside.That research established a relationship between nestmate recognition and the clearly defined, age-dependent division of labor typical to honey bee hives.Only when a bee is old enough to interact with others outside of the hive does it become recognizable to others. That was a clue for the researchers."If you grow a honey bee in isolation, it will never develop a complete microbiome," Vernier said. "It actually has to acquire most of it from interactions with other bees."For this study, researchers determined that forager bees from different honey bee colonies have different gut microbial communities and CHC profiles by sequencing gut samples and analyzing cuticular extracts. The scientists also conducted cross-hive fostering experiments, raising groups of newly hatched bees in either their own colonies or unrelated colonies.In the fostering experiments, the researchers found that both source- and host-colony related factors contribute to variations in the overall gut microbial community of individual bees. Of the 14 microbial taxa that significantly differed between treatments, six were similar between bees that shared the same hive environment while they grew up -- regardless of actual genetic relatedness.The researchers also found that they could manipulate the microbiome of sister bees by feeding different microbes to newly hatched bees. In addition to developing different gut microbial communities, the bees also grew to have different CHC profiles."They were unrecognizable to their siblings," Vernier said. "Manipulating the microbiome was enough to cause sister bees to develop different scent profiles."This new work is significant in part because it shows an integral role for the microbiome in the essential, everyday social interactions of honey bees, the Earth's most important pollinators, researchers said."For bees, some of the most complex aspects of their social behavior basically depends on bacteria -- more than anything else!" Ben-Shahar said."It doesn't matter how related they are," he said. "Their ability to say 'you belong to this group' basically depends on getting the right bacteria at the right time. Otherwise, they are blind to it."And bee ID is key.The biggest enemy to honey bees is other bees."During fall, when plants stop producing nectar, there is a period of time when robbing is very prevalent in colonies," Vernier said. "Robbing bees will find other colonies, and if they're able to get in and take some honey, they will go back to their own nests and signal, 'Hey, go over there. There's a nest that's not good at guarding, and we can steal their honey.'"Robber bees will take that honey and leave the other colony to starve," she said. "It's a very strong pressure."Robbing deprives both the host bees and their associated bacteria with important resources -- which may have been the original drive to form this special bacteria-animal partnership, the researchers said.
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Agriculture & Food
| 2,020 |
October 14, 2020
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https://www.sciencedaily.com/releases/2020/10/201014141041.htm
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More diversity needed in oil palm plantations
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The growing global demand for palm oil has led to a rapid spread of oil palm monoculture plantations in South East Asia. This is often associated with the loss of natural habitat and biodiversity. Oil palm monocultures are uniformly structured and therefore offer little space for different species. Diversification using indigenous tree species can contribute to maintaining biodiversity. A research team from the University of Göttingen (Germany) and the University of Jambi (Indonesia) has now shown that such diversification can be encouraged with the help of information campaigns and free seedlings. The study has been published in the
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Oil palm plantations cultivated by smallholder farmers account for about 40 percent of the total area of oil palms in Indonesia, which means they are an important target group for interventions. The study of the interdisciplinary German-Indonesian Collaborative Research Centre "EFForTS" involved 800 smallholder farmers. "Smallholder farmers have little access to information, advice and high-quality seeds," says study director Professor Meike Wollni, agricultural economist at the University of Göttingen. "Yet, there is a high level of interest in diversification, especially with native fruit trees, as expressed by the local population in focus group discussions."Against this background, the researchers divided the participants in the study into different treatment groups. The groups received information and/or tree seedlings. The results show that the two measures being investigated increase the number of trees planted in smallholder oil palm plantations. "We see that both interventions motivate a small group of individuals to plant many trees," says first author Dr Katrin Rudolf from the University of Göttingen. "However, to reach a large number of farmers, it is necessary to distribute seedlings. Here, the farmers' preferences should be taken into account when selecting tree species in order to increase the tree survival."Identifying policies to improve the environmental impact of oil palm cultivation is highly relevant in the context of ongoing species loss, according to the authors. In addition to the supply side, however, the demand side should be considered when designing policies. Consumers could, for example, contribute to the costs incurred through certification of more environmentally friendly plantations.
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Agriculture & Food
| 2,020 |
October 10, 2020
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https://www.sciencedaily.com/releases/2020/10/201010135507.htm
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Planting parasites: Unveiling common molecular mechanisms of parasitism and grafting
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Using the model Orobanchaceae parasitic plant
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Plant parasitism is a phenomenon by which the parasite plant latches onto and absorbs water and nutrients from a second host plant, with the help of a specialized organ called the "haustorium." Once the haustorium forms, specific enzymes then help in forming a connection between the tissues of the parasite and host plants, known as a "xylem bridge," which facilitates the transport of water and nutrients from the host to the parasite.A similar mechanism is involved in the process of artificial stem grafting, during which, the cell walls of the two different plant tissues at the graft junction become thinner and compressed, a phenomenon made possible by specific cell wall modifying enzymes. Cell wall modification has also been implicated to play a role in parasitism in different lineages of parasitic plants.Therefore, the research team, led by Dr Ken-ichi Kurotani of Nagoya University, hypothesized that similar genes and enzymes should be involved in the process of parasitism and cross-species grafting. "To investigate molecular events involved in cell-cell adhesion between P. japonicum and the host plant, we analyzed the transcriptome for P. japonicum-Arabidopsis parasitism and P. japonicum-Arabidopsis grafting," reports Dr Kurotani. When a gene in a cell is activated, it produces an RNA "transcript" that is then translated into an active protein, which is then used by the cell to perform various activities. A "transcriptome" is the complete set of RNA transcripts that the genome of an organism produces under various diverse conditions. The findings of their experiments are published in Nature's Communications Biology.Comparison of the parasitism and graft transcriptomes revealed that genes associated with wound healing, cell division, DNA replication, and RNA synthesis were highly upregulated during both events, indicating active cell proliferation at both the haustorium and graft interface."What's more, we found an overlap between the transcriptome data from this study and that from grafting between Nicotiana and Arabidopsis, another angiosperm," reports Dr Michitaka Notaguchi, the co-corresponding author of the study. Glycosyl hydrolases are enzymes that specifically target the breakdown of cellulose, the primary component of plant cell walls. A β-1,4-glucanase identified in P. japonicum belongs to the glycosyl hydrolase 9B3 (GH9B3) family; an enzyme from the same family was recognized to be crucial for cell-cell adhesion in Nicotiana by Dr Notaguchi's group.Further experiments showed that GH9B3-silenced P. japonicum could form the haustorium with Arabidopsis but could not form a functional xylem bridge, meaning that the P. japonicum β-1,4-glucanase is integral for the plant's parasitic activity. Further, high GH9B3 RNA transcript levels were observed during artificial grafting experiments, thereby proving that the enzyme plays an integral role in both parasitism and grafting mechanisms.The transcriptome data generated in this study can be used to unearth additional genes and enzymes involved in plant parasitism. Additionally, further research along these directions will help scientists develop specific molecular approaches to arrive at sustainable cross-species grafting alternatives.
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Agriculture & Food
| 2,020 |
October 8, 2020
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https://www.sciencedaily.com/releases/2020/10/201008121308.htm
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Crabs are key to ecology and economy in Oman
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The intertidal mudflats of Barr Al Hikman, a nature reserve at the south-east coast of the Sultanate Oman, are crucial nursery grounds for numerous crab species. In return, these crabs are a vital element of the ecology, as well as the regional economy, a new publication in the scientific journal
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The mudflats of Barr Al Hikman are home to almost thirty crab species. For his research, Bom, together with colleagues in The Netherlands and at the Sultan Qaboos University in Oman, looked at the ecology of the two most abundant species. Bom: 'Barr Al Hikman is also home to the blue swimming crab Portunus segnis. That is the species caught by local fishermen. This crab uses the mudflats of Barr Al Hikman as nursery grounds.'The counts of Bom and his colleagues show, that there are millions and millions of these crabs in Barr Al Hikman. They are food to hundreds of thousands of birds, both migrating species, as well as birds breeding in the area, such as crab plovers. The crabs live in holes in the ground. They forage on the seagrass beds that are still abundant in Barr Al Hikman. 'Apart from the high primary production (algae) in Barr al Hikman, this reserve is also well suited for crabs because of the vastness of the area', Bom assumes. 'The slopes of the mudflats are very gentle, so at low tide, the crabs have an immense area at their disposition.'The value of the crabs is not just ecological, Bom stresses. "Local fishermen that catch the blue swimming crabs, distribute them not only through Oman, but also through the rest of the Arabian Peninsula and even to Japan. At approximately € 2,- per kilo, these crabs represent an important economic pillar, both under the region around Barr Al Hikman, as well as for the whole of Oman.'The protection of the reserve of Barr Al Hikman is limited to national legislation. Efforts to acknowledge this reserve under the international Ramsar-convention were never effectuated. There is, however, increasing human pressure on the mudflats of Barr Al Hikman, the authors describe, that would justify further protection. For example, there are well-developed plans to start shrimp farming around this intertidal area. 'When looking at the cost and benefits of these activities, it is important to look at the role of this reserve in the local ecology, as well as in the broader ecology of the many migratory birds that use the area', Bom says. 'Moreover, our research shows that the unique ecosystem of Barr Al Hikman plays a key role in the economy as well.'
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Agriculture & Food
| 2,020 |
October 8, 2020
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https://www.sciencedaily.com/releases/2020/10/201008121302.htm
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Dietary migration of Impala rivals the geographical migration of Serengeti wildebeest
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African savannas are renowned for their huge diversity of wildlife, yet some animal species are much more abundant than others. What causes these differences?
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For herbivore species -- plant-eating animals like antelope, zebra and elephants -- the challenge lies in both obtaining enough food to eat throughout the year, while also avoiding predation by carnivores.One way to obtain enough food -- and which works extremely well in places like the Serengeti -- is to migrate over long distances and track the areas where the best food is available through the seasonal cycle. This works best for grass eating or 'grazer' species such as wildebeest and zebra.On the other hand, being extremely large like an elephant greatly reduces predation risk, with their big bodies also meaning that they can eat whatever they like, because there is lots of time to digest foods as they move through their long gut system.So why then are impala by far the most abundant herbivore in a place like the Kruger Park? These are animals that do not migrate, and they are also only medium-sized at best.Recent research published in "The key insight emerging from our research is that species like impala do actually migrate, although not in the sense you would expect," says Dr Hempson. "For impala, the migration they undertake is a 'dietary migration', where they switch from eating mostly grass in the wet season, to eating more tree leaves or 'browse' during the dry season. This 'mixed feeding' strategy makes a huge amount of sense, because grasses tend to be higher quality and more abundant food in the wet season, but trees tend to stay greener much longer into the dry season and become the better food source then."Theoretical models show that for this 'mixed feeding' strategy to work, the costs of switching between food sources must not be too high. For example, the mouth shape of a hippo is excellent for consuming lots of grass quickly, but terrible for picking green leaves out of a thorn tree. Similarly, giraffe are better off sticking to browsing from the treetops. The models also suggest that for the mixed feeding strategy to be advantageous, the 'best' food type must change from season to season. This is typically the case for grass versus browse in savannas.Animal census data from 18 protected areas in East and southern Africa show that being a mixed feeder does indeed have a strong positive effect on species abundances in savannas, regardless of body size. In fact, the abundance of mixed feeders is rivalled only by migratory grazers, suggesting that switching your diet from season to season -- either in terms of what you eat, or where you eat -- is fundamental to achieving high population sizes.But what of the benefits of being large-bodied like an elephant? This research suggests that part of the reason why elephants can become abundant is in fact due to their broad, mixed diets, but the anti-predation benefits of being large almost certainly still stand. However, outsized human poaching effort on very large species such as rhino and elephant mean that we have little idea of just how abundant they really can be.The findings of this research have important implications for the management and conservation of increasingly threatened herbivore populations, and for our understanding of the ecology of savannas more broadly. For example, land use change and the shrinking space available for animal movement means that mixed feeders -- who can switch their diet in situ -- are likely to fare better in future than species that historically would have moved long distances to obtain different food sources. Mixed feeders may also come to play an increasingly important role in mitigating woody encroachment -- the rapid increase in tree density in many savannas linked to rising carbon dioxide levels -- thus maintaining more open, grassy spaces to the benefit of grazing species."So, next time you're in the Kruger Park and becoming bored of seeing only impala, take a moment to reflect that you are witnessing the outcome of a migration that rivals that of the Serengeti wildebeest -- an extraordinary seasonal dietary migration from grass to browse," says Dr Hempson.
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Agriculture & Food
| 2,020 |
October 8, 2020
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https://www.sciencedaily.com/releases/2020/10/201008121248.htm
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Genomic study reveals evolutionary secrets of banyan tree
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The banyan fig tree
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In a new study, researchers identify regions in the banyan fig's genome that promote the development of its unusual aerial roots and enhance its ability to signal its wasp pollinator.The study, published in the journal Understanding the evolutionary history of Ficus species and their wasp pollinators is important because their ability to produce large fruits in a variety of habitats makes them a keystone species in most tropical forests, said Ray Ming, a plant biology professor at the University of Illinois, Urbana-Champaign who led the study with Jin Chen, of the Chinese Academy of Sciences. Figs are known to sustain at least 1,200 bird and mammal species. Fig trees were among the earliest domesticated crops and appear as sacred symbols in Hinduism, Buddhism and other spiritual traditions.The relationship between figs and wasps also presents an intriguing scientific challenge. The body shapes and sizes of the wasps correspond exactly to those of the fig fruits, and each species of fig produces a unique perfume to attract its specific wasp pollinator.To better understand these evolutionary developments, Ming and his colleagues analyzed the genomes of the two fig species, along with that of a wasp that pollinates the banyan tree."When we sequenced the trees' genomes, we found more segmental duplications in the genome of the banyan tree than in The duplications increased the number of genes involved in the synthesis and transport of auxins, a class of hormones that promote plant growth. The duplicated regions also contained genes involved in plant immunity, nutrition and the production of volatile organic compounds that signal pollinators."The levels of auxin in the aerial roots are five times higher than in the leaves of trees with or without aerial roots," Ming said. The elevated auxin levels appear to have triggered aerial root production. The duplicated regions also include genes that code for a light receptor that accelerates auxin production.When they studied the genome of the fig wasp and compared it with those of other related wasps, the researchers observed that the wasps were retaining and preserving genes for odorant receptors that detect the same smelly compounds the fig trees produce. These genomic signatures are a signal of coevolution between the fig trees and the wasps, the researchers report.Ming and his colleagues also discovered a Y chromosome-specific gene that is expressed only in male plants of "This gene had been duplicated twice in the dioecious genomes, giving the plants three copies of the gene. But Ficus species that have male and female flowers together on one plant have only one copy of this gene," Ming said. "This strongly suggests that this gene is a dominant factor affecting sex determination."
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Agriculture & Food
| 2,020 |
October 8, 2020
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https://www.sciencedaily.com/releases/2020/10/201008083801.htm
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Pollinator monitoring more than pays for itself
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Monitoring schemes to count bees and other pollinating insects provide excellent value for money, and could help save species and protect UK food security, researchers have found.
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The study led by the University of Reading and the UK Centre for Ecology & Hydrology, found that the costs of running nationwide monitoring schemes are more than 70 times lower than the value of pollination services to the UK economy, and provide high quality scientific data at a much lower cost than running individual research projects.Dr Tom Breeze, an ecological economist at the University of Reading, led the research. He said: "Pollinating insects are the unsung, unpaid heroes of British farming, but we know many species need help. Pollinators are vital for our food security and natural ecosystems but are under threat from many factors including habitat loss and climate change."Our analysis shows that large-scale and long-term pollinator monitoring schemes can be cost-effective and add tremendous value to food security and wider scientific research."Monitoring insect pollinators, such as wild bees and hoverflies, is vital to understanding where and why they are declining in order to better target efforts to protect them. National pollinator strategies for England, Scotland, Wales and Ireland have highlighted monitoring as a priority for government action, but need to compete with other funding needs.This new study, published in the Senior author Dr Claire Carvell of the UK Centre for Ecology & Hydrology, who is coordinator of the UK Pollinator Monitoring and Research Partnership, said: "Monitoring bees and other pollinators is challenging due to the sheer number of species involved, the difficulty in identifying them and the shortage of specialist skills needed."This research has been instrumental in helping design a world-leading Pollinator Monitoring Scheme (PoMS) for the UK which combines both professional and volunteer involvement, and generates data for research and policy that we can't really accomplish with standard research grants. And at a lower cost too."Rebecca Pow MP, Minister for Pollinators at Defra, said: "This year, we have seen an increased appreciation for nature in England in response to the Coronavirus pandemic and the nation building back greener."The UK Pollinator Monitoring Scheme (PoMS) is an excellent way to inspire people to take action to protect our pollinators. Our pollinators may be small, but they play a key role in our ecosystem, and this scheme creates world-leading evidence helping us to better understand their status."It's tremendously positive to see the UK government and devolved administrations, research institutions and the public working together to understand these essential and precious creatures."Researchers looked at the costs compared with the monetary benefits of monitoring schemes. Working with a range of scientists and experts in wildlife management, the team calculated how much it would cost to run various different types of monitoring scheme for 10 years. These ranged from schemes where all the work was handled by professional research staff, to schemes where members of the public work with scientists to collect the data.The costs calculated ranged from £6,000/year for a volunteer scheme collecting counts of insects visiting flowers, to £300,000/year for a scheme involving both volunteers and professionals to collect and process the data; £900,000/year for a professional scheme using more intensive sampling to collect species-level pollinator data and up to £2.7M/year for a professional scheme to monitor the pollination and yields of the UK's crops for shortfalls.Using information from field research, the team explored the impact of pollinator losses on the yields of insect pollinated crops grown in the UK. These include apples, berries, beans, oilseed rape and tomatoes. This potential loss of yield, given a 30% decline in pollinator numbers over 10 years, was estimated at over £188M per year, 70 times the costs of even the most expensive monitoring scheme to track and respond to declines.The team also compared the monitoring scheme costs with the costs of carrying out a series of separate studies answering different questions. This was done by surveying pollinator researchers from across Europe about how they would design studies to answer eight key research questions, such as, the impact of climate change, and whether current farmland conservation measures are working.The cost of implementing all these studies was compared with the costs of a pollinator monitoring scheme to show the value added by monitoring to UK science.The study demonstrated that well-designed monitoring schemes provide excellent value for money, providing data to answer these eight big research questions for at least 33% less cost than traditional research funding models.Volunteers already contribute to our understanding of the status of wildlife by recording species that they see and sharing this information. There are a number of established, professionally-coordinated monitoring schemes involving volunteers, for example the UK Butterfly Monitoring Scheme and the Breeding Bird Survey.Additionally there are well-established wildlife recording schemes such as the Bees, Wasps and Ants Recording Society and the Hoverfly Recording Scheme. By combining the strengths of professionals and often highly-skilled volunteers, these citizen science approaches are invaluable in providing information at scales that would not otherwise be practical.Professor Helen Roy of the UK Centre for Ecology & Hydrology said: "It is incredibly exciting to consider the benefits to people and nature achieved through the implementation of the Pollinator Monitoring Scheme. Volunteers can play a critical role in gathering much needed data from across Britain while increasing everyone's understanding of these important and much loved insects."The authors conclude that pollinator monitoring is an excellent investment that supports UK food security and environmental science, and helps conserve iconic British species.
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Agriculture & Food
| 2,020 |
October 6, 2020
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https://www.sciencedaily.com/releases/2020/10/201006153514.htm
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Pesticides and food scarcity dramatically reduce wild bee population
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The loss of flowering plants and the widespread use of pesticides could be a double punch to wild bee populations. In a new study, researchers at the University of California, Davis, found that the combined threats reduced blue orchard bee reproduction by 57 percent and resulted in fewer female offspring. The study was published in the journal
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"Just like humans, bees don't face one single stress or threat," said lead author Clara Stuligross, a Ph.D. candidate in ecology at UC Davis. "Understanding how multiple stressors interplay is really important, especially for bee populations in agricultural systems, where wild bees are commonly exposed to pesticides and food can be scarce."The study found that pesticide exposure had the greatest impact on nesting activity and the number of offspring the bees produced. Pesticide exposure reduced bee reproduction 1.75 times more than limiting their food.The team conducted their research by exposing the blue orchard bee to the neonicotinoid insecticide imidacloprid, the most widely used neonicotinoid in the United States. It's also among the most frequently applied insecticides in California.Nesting female bees were set up in large flight cages containing wildflowers at high or low densities treated with and without the insecticide. The insecticide was applied based on label instructions. Bees can be exposed to insecticides by consuming pollen and nectar from the treated flowers. Similar research has been conducted on honeybees in labs, but there has been no comparable research on wild bees in field or semi-field conditions.The two main factors that affect bee reproduction are the probability that females will nest and the total number of offspring they have. The research found that pesticide-exposed and resource-deprived female bees delayed the onset of nesting by 3.6 days and spent five fewer days nesting than unexposed bees.Co-author Neal Williams, a pollination ecologist and professor in the Department of Entomology and Nematology at UC Davis, said that's a substantial delay considering bees only nest for a few weeks. The production of female bees is also crucial to determining the health of future bee populations."In the bee world, males don't matter so much," said Williams. "Male numbers rarely limit population growth, but fewer females will reduce the reproductive potential of subsequent generations."The study found pesticide exposure dramatically reduced the probability that a bee produced even a single daughter. Of all nesting females, only 62 percent of pesticide-exposed bees produced at least one daughter compared to 92 percent of bees not exposed to pesticides.Study authors said the research can help farmers make decisions about how they manage the environment around orchards. It reinforces the need for growers to carefully think about the location where they plant flowers for bee forage, to prevent flowers from becoming traps that expose bees to pesticides.The study was supported by a UC Davis Jastro Research Award, a UC Davis Ecology Graduate Research Fellowship, a National Science Foundation Graduate Research Fellowship, and the UC Bee Biology Facility.
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Agriculture & Food
| 2,020 |
October 5, 2020
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https://www.sciencedaily.com/releases/2020/10/201005122131.htm
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Shattering expectations: Novel seed dispersal gene found in green millet
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For years, Elizabeth (Toby) Kellogg, PhD, member and Robert E. King Distinguished Investigator and other researchers at the Donald Danforth Plant Science Center (Danforth Center) drove up and down the highways of the continental United States, occasionally pulling over to the side of the road to collect small weedy plants and bring them back to the lab. The weedy grass was green millet (Setaria viridis), a small model grass with a short lifecycle that uses a carbon fixation process known as the C4 pathway, which particularly helps plants thrive in warm, arid environments. Corn and sugarcane are among the major high-yield C4 crops, as are the candidate biofuel feedstocks Miscanthus and switchgrass.
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Innumerable road trips and hundreds of plants have resulted in a paper, "A genome resource for green millet Setaria viridis enables discovery of agronomically valuable loci," in Nature Biotechnology. Kellogg and her colleagues, along with researchers at the HudsonAlpha Institute for Biotechnology and the U.S. Department of Energy (DOE) Joint Genome Institute (JGI), a DOE Office of Science User Facility located at Lawrence Berkeley National Laboratory (Berkeley Lab), generated genome sequences for nearly 600 green millet plants and released a very high quality reference S. viridis genome sequence. Analysis of these plant genome sequences also led researchers to identify a gene related to seed dispersal in wild populations for the first time."To our knowledge, nobody has ever discovered a dispersal gene that way," said Kellogg, a senior author of the paper. "This paper is the first one to survey a huge amount of natural diversity and say, 'Yeah, there are genes out there that affect this phenotype.'"Seed dispersal is critical for plants in the wild, but it is an undesirable trait for domesticated crops because it leads to reduced harvest yields. Over thousands of years, farmers have selected for cereal plants without this shattering trait -- referring to the moment when the cluster of seeds at the tip of each branch breaks apart so the seeds can disperse -- so that the seeds remain atop the plant to be collected.Association mapping led the team to identify a gene called Less Shattering 1 (SvLes1); gene editing studies led by co-first author Pu Huang confirmed that it was involved in shattering by turning it off. "It's a new shattering gene variant identified in a natural population. Not very many of these shattering genes have been discovered that let a plant go all the way to seed but prevent the seeds from falling," said JGI Plant Program head Jeremy Schmutz, who is also a HudsonAlpha Faculty Investigator. "This could be another mechanism to turn off shattering and domesticate crops." How shattering occurs varies widely between crops, Kellogg added, and shattering genes may be specific to species or groups of species.The genome data also revealed that green millet was introduced into the United States multiple times from Eurasia. The team also identified a gene associated with leaf angle, which determines how much sunlight leaves can get and in turn serves as a predictor of yield. The gene is an ortholog of known genes, "The gene has now been mapped back in maize as involved in leaf angle," noted Schmutz. "It's a nice example of de novo discovery and then mapping back to identify candidate genes."Through JGI's Community Science Program, sequences of several hundred green millet plant genomes were generated, though the final analyses focused on 598 individuals. Schmutz and his team assembled and annotated the genomes at HudsonAlpha. Sujan Mamidi and Adam Healey, two of the co-first authors, led the data analyses and assembled the green millet "pan-genome" (a set of 51,000 genes that represent all the genes that are present in a given species)."This is a great example of developing a large-scale genome infrastructure with a reasonably accessible system," said Schmutz. "Building the pan-genome and accessions allow us to see presence/absence variation easily and to find genes missing in particular accessions, and to confirm phenotypes, which validate traits.""The number of lines sequenced is not trivial, and they were all assembled de novo, which let the team look at presence/absence of whole genes," Kellogg agreed. "Getting that information is hard. There's a good reason nobody's done it; it's a heck of a lot of work. I wouldn't have done it without the contribution of Jeremy's group. It's just a massive amount of sequencing."Kellogg noted that C4 crops have gotten a lot of interest because they're very productive even in high heat while C3 crops have become less efficient at photosynthesis, a concern as extreme weather events become more frequent. "A big part of the Danforth Center's mission is to feed the hungry and improve human health. So there's a major question: how to turn a C3 crop into a C4 crop. There should be a master regulator but no one has found it," Kellogg mused. "[The S. viridis genome] is a resource for many different applications. The JGI group has been wonderful to collaborate with, and this [project] wouldn't have been possible without their involvement; it's something we wouldn't have even started."Researchers from the RIKEN Center for Sustainable Resource Science (Japan) and Chinese Academy of Agricultural Sciences (China) were also involved in this work.
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Agriculture & Food
| 2,020 |
October 5, 2020
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https://www.sciencedaily.com/releases/2020/10/201005101515.htm
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Efficient pollen identification
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From pollen forecasting, honey analysis and climate-related changes in plant-pollinator interactions, analysing pollen plays an important role in many areas of research. Microscopy is still the gold standard, but it is very time consuming and requires considerable expertise. In cooperation with Technische Universität (TU) Ilmenau, scientists from the Helmholtz Centre for Environmental Research (UFZ) and the German Centre for Integrative Biodiversity Research (iDiv) have now developed a method that allows them to efficiently automate the process of pollen analysis. Their study has been published in the specialist journal
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Pollen is produced in a flower's stamens and consists of a multitude of minute pollen grains, which contain the plant's male genetic material necessary for its reproduction. The pollen grains get caught in the tiny hairs of nectar-feeding insects as they brush past and are thus transported from flower to flower. Once there, in the ideal scenario, a pollen grain will cling to the sticky stigma of the same plant species, which may then result in fertilisation. "Although pollinating insects perform this pollen delivery service entirely incidentally, its value is immeasurably high, both ecologically and economically," says Dr. Susanne Dunker, head of the working group on imaging flow cytometry at the Department for Physiological Diversity at UFZ and iDiv. "Against the background of climate change and the accelerating loss of species, it is particularly important for us to gain a better understanding of these interactions between plants and pollinators." Pollen analysis is a critical tool in this regard.Each species of plant has pollen grains of a characteristic shape, surface structure and size. When it comes to identifying and counting pollen grains -- measuring between 10 and 180 micrometres -- in a sample, microscopy has long been considered the gold standard. However, working with a microscope requires a great deal of expertise and is very time-consuming. "Although various approaches have already been proposed for the automation of pollen analysis, these methods are either unable to differentiate between closely related species or do not deliver quantitative findings about the number of pollen grains contained in a sample," continues UFZ biologist Dr. Dunker. Yet it is precisely this information that is critical to many research subjects, such as the interaction between plants and pollinators.In their latest study, Susanne Dunker and her team of researchers have developed a novel method for the automation of pollen analysis. To this end they combined the high throughput of imaging flow cytometry -- a technique used for particle analysis -- with a form of artificial intelligence (AI) known as deep learning to design a highly efficient analysis tool, which makes it possible to both accurately identify the species and quantify the pollen grains contained in a sample. Imaging flow cytometry is a process that is primarily used in the medical field to analyse blood cells but is now also being repurposed for pollen analysis. "A pollen sample for examination is first added to a carrier liquid, which then flows through a channel that becomes increasingly narrow," says Susanne Dunker, explaining the procedure. "The narrowing of the channel causes the pollen grains to separate and line up as if they are on a string of pearls, so that each one passes through the built-in microscope element on its own and images of up to 2,000 individual pollen grains can be captured per second." Two normal microscopic images are taken plus ten fluorescence microscopic images per grain of pollen. When excited with light radiated at certain wavelengths by a laser, the pollen grains themselves emit light. "The area of the colour spectrum in which the pollen fluoresces -- and at which precise location -- is sometimes very specific. This information provides us with additional traits that can help identify the individual plant species," reports Susanne Dunker. In the deep learning process, an algorithm works in successive steps to abstract the original pixels of an image to a greater and greater degree in order to finally extract the species-specific characteristics. "Microscopic images, fluorescence characteristics and high throughput have never been used in combination for pollen analysis before -- this really is an absolute first." Where the analysis of a relatively straightforward sample takes, for example, four hours under the microscope, the new process takes just 20 minutes. UFZ has therefore applied for a patent for the novel high-throughput analysis method, with its inventor, Susanne Dunker, receiving the UFZ Technology Transfer Award in 2019.The pollen samples examined in the study came from 35 species of meadow plants, including yarrow, sage, thyme and various species of clover such as white, mountain and red clover. In total, the researchers prepared around 430,000 images, which formed the basis for a data set. In cooperation with TU Ilmenau, this data set was then transferred using deep learning into a highly efficient tool for pollen identification. In subsequent analyses, the researchers tested the accuracy of their new method, comparing unknown pollen samples from the 35 plant species against the data set. "The result was more than satisfactory -- the level of accuracy was 96 per cent," says Susanne Dunker. Even species that are difficult to distinguish from one another, and indeed present experts with a challenge under the microscope, could be reliably identified. The new method is therefore not only extremely fast but also highly precise.In the future, the new process for automated pollen analysis will play a key role in answering critical research questions about interactions between plants and pollinators. How important are certain pollinators like bees, flies and bumblebees for particular plant species? What would be the consequences of losing a species of pollinating insect or a plant? "We are now able to evaluate pollen samples on a large scale, both qualitatively and- at the same time -- quantitatively. We are constantly expanding our pollen data set of insect-pollinated plants for that purpose," comments Susanne Dunker. She aims to expand the data set to include at least those 500 plant species whose pollen is significant as a food source for honeybees.
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Agriculture & Food
| 2,020 |
October 5, 2020
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https://www.sciencedaily.com/releases/2020/10/201005080857.htm
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Dozens of mammals could be susceptible to SARS-CoV-2
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Numerous animals may be vulnerable to SARS-CoV-2, the virus that causes Covid-19, according to a large study modelling how the virus might infect different animals' cells, led by UCL researchers.
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The study, published in The researchers investigated how the spike protein from SARS-CoV-2 could interact with the ACE2 protein it attaches to when it infects people.The focus of the investigation was whether mutations in the ACE2 protein in 215 different animals, that make it different from the human version, would reduce the stability of the binding complex between the virus protein and host protein. Binding to the protein enables the virus to gain entry into host cells; while it is possible the virus might be able to infect animals via another pathway, it is unlikely based on current evidence that the virus could infect an animal if it cannot form a stable binding complex with ACE2.The researchers found that for some animals, such as sheep and great apes (chimpanzee, gorilla, orangutan, and bonobo, many of which are endangered in the wild), the proteins would be able to bind together just as strongly as they do when the virus infects people. Some of the animals, such as sheep, have not yet been studied with infection tests, so this does not confirm that the animal can indeed be infected.Lead author Professor Christine Orengo (UCL Structural & Molecular Biology) said: "We wanted to look beyond just the animals that had been studied experimentally, to see which animals might be at risk of infection, and would warrant further investigation and possible monitoring."The animals we identified may be at risk of outbreaks that could threaten endangered species or harm the livelihoods of farmers. The animals might also act as reservoirs of the virus, with the potential to re-infect humans later on, as has been documented on mink farms."The research team also performed more detailed structural analyses for certain animals, to gain a better understanding of how infection risks may differ across animal species. By comparing their findings to other experimental data, they set thresholds to predict which animals are at risk of infection, and which ones most likely cannot be infected.They found that most birds, fish, and reptiles do not appear to be at risk of infection, but the majority of the mammals they reviewed could potentially be infected.Professor Orengo added: "The details of host infection and severity of response are more complex than just the interactions of the spike protein with ACE2, so our research is continuing to explore interactions involving other host virus proteins."The team's findings mostly agree with experiments conducted in living animals and with reported cases of infections. They predict possible infection in domestic cats, dogs, mink, lions, and tigers, all of which have had reported cases, as well as ferrets and macaques, which have been infected in laboratory studies.First author, Su Datt Lam (UCL Structural & Molecular Biology and the National University of Malaysia) said: "Unlike laboratory-based experiments, the computational analyses we devised can be run automatically and rapidly. Therefore, these methods could be applied easily to future virus outbreaks that, unfortunately, are becoming more common due to human encroachment into natural habitats."Co-author Professor Joanne Santini (UCL Structural & Molecular Biology) said: "To protect animals, as well as to protect ourselves from the risk of one day catching Covid-19 from an infected animal, we need large-scale surveillance of animals, particularly pets and farm animals, to catch cases or clusters early on while they're still manageable."It may also be important to employ hygiene measures when dealing with animals, similar to the behaviours we've all been learning this year to reduce transmission, and for infected people to isolate from animals as well as from other people."The study was conducted by researchers in UCL Biosciences, UCL Science & Technology Studies, National University of Malaysia, King's College London, and Oxford Brookes University, and was supported by Wellcome, the Newton Fund UK-China NSFC initiative, BBSRC, EDCTP PANDORA-ID NET, NIHR UCLH/UCL Biomedical Research Centre, and the Medical Research Council.
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Agriculture & Food
| 2,020 |
October 2, 2020
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https://www.sciencedaily.com/releases/2020/10/201002153617.htm
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Harvesting vegetation on riparian buffers barely reduces water-quality benefits
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Allowing farmers to harvest vegetation from their riparian buffers will not significantly impede the ability of those streamside tracts to protect water quality by capturing nutrients and sediment -- and it will boost farmers' willingness to establish buffers.
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That is the conclusion of Penn State College of Agricultural Sciences researchers, who compared the impacts of six riparian buffer design scenarios over two, four-year crop rotations in two small central and southeastern Pennsylvania watersheds. Two of the buffer scenarios included the harvesting of switchgrass and swamp willow trees.Allowing farmers to harvest vegetation from their riparian buffers and sell it for biofuels -- not permitted under current Conservation Reserve Enhancement Program, or CREP, federal regulations -- would go a long way toward persuading farmers to establish riparian buffers, researchers contend. And farmers' buy-in is badly needed in Pennsylvania, where hundreds of miles of new buffers are needed along streams emptying into the Chesapeake Bay to help the state meet water-quality standards."This is the first long-term study in the Chesapeake Bay watershed to model how harvesting vegetation affects riparian buffer performance over the full length of a buffer contract," said researcher Heather Preisendanz, associate professor of agricultural and biological engineering. "Allowing harvesting of the buffer vegetation -- either trees or grasses -- minimally impacted water quality, with only slight annual average reductions in the capture of nitrogen, phosphorus and sediment."In addition, she noted, under the highest input loading conditions -- heavy runoff after storms -- buffers with lower removal efficiencies removed more total mass of pollutants than did buffers with high-removal efficiencies, if they were between streams and fields with row crops such as corn and soybeans. The location of the buffer was most important.The researchers, who modeled runoff and resulting pollution from agricultural fields reaching the streams, studied riparian buffer performance on Spring Creek in Centre County and Conewago Creek in Lancaster County. Buffer design scenarios studied included 35-feet-wide grass; 50-feet-wide grass; 50-feet-wide deciduous trees; 100-feet-wide grass and trees; 100-feet-wide grass and trees, with trees harvested every three years; and 100-feet-wide grass and trees, with grass harvested every year.The research team developed these scenarios after considering feedback from focus group meetings with farmers in the two watersheds. Farmers indicated they wanted to be able to install buffers tailored to their properties with the prospect of generating limited revenue.In the Spring Creek watershed -- which has been studied closely by Penn State agricultural scientists for decades -- 16 years of daily-scale nutrient and sediment loads from three crop rotations and two soils were simulated in a soil and water assessment tool. That data was used as an input to a riparian ecosystem management model used nationally to better understand how a buffer's effectiveness changes as a function of input load, buffer design and buffer management.The simulation results, recently published in the The findings of the research have important implications for informing flexible buffer design policies and enhanced placement of buffers in watersheds impaired by nutrient and sediment, Preisendanz explained. She pointed out, however, that more research may be needed to examine tradeoffs between water-quality impacts and other ecosystem services, such as streambank stabilization, habitat and stream shading."If incorporated into policy, these findings could remove one barrier to farmer adoption of riparian buffers," she said. "Based on our conversations with famers in focus groups, we think this approach -- government being more flexible with buffer designs and allowing harvesting -- would go a long way toward farmers agreeing to create more riparian buffers."The state Department of Conservation and Natural Resources currently is promoting "multifunctional" buffers, Preisendanz added. "Our hope is that this work will help to inform tradeoffs of flexible buffer designs and management options in this new program."
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Agriculture & Food
| 2,020 |
October 2, 2020
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https://www.sciencedaily.com/releases/2020/10/201002093839.htm
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Potential new tool for frost screening in crops
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Agricultural scientists and engineers at the University of Adelaide have identified a potential new tool for screening cereal crops for frost damage.
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Their research, published this week in the journal "Frost is estimated to cost Australian grain growers $360 million in direct and indirect losses every year," says project leader Professor Jason Able, at the University's School of Agriculture, Food and Wine."To minimise significant economic loss, it is crucial that growers' decisions on whether to cut the crop for hay or continue to harvest are made soon after frost damage has occurred. However, analysing the developing grains for frost damage is difficult, time-consuming and involves destructive sampling."Frost damage can happen when the reproductive organs of the plant are exposed to air temperatures below 0°C during the growing season, with the amount of damage dependent on the severity and occurrence of frost events.Cereal crops like barley and wheat show a wide range of susceptibility to frost damage depending on the genetics, management practices, environmental conditions and their interactions. For example, one-degree difference in temperature could result in frost damage escalating from 10% to 90% in wheat.Supported by the University's Waite Research Institute and the Grains Research and Development Corporation, the researchers tested whether a state-of-art imaging system at the Terahertz Engineering Laboratory in the School of Electrical and Electronic Engineering, could be used to scan both barley and wheat spikes for frost damage.Terahertz waves are able to penetrate the spike to determine differences between frosted and unfrosted grains."Barley and wheat spikes subjected to frost do not necessarily show symptoms for many days until after the frost event," says Professor Able. "This technology holds promise for identifying frost damage before symptoms can be visibly detected."The researchers, including Dr Wendy Lee, Dr Ariel Ferrante and Associate Professor Withawat Withayachumnankul, found that terahertz imaging can discriminate between frosted and unfrosted barley spikes, and that the results were repeatable over many scans. This imaging technology was also able to determine individual grain positions along the length of the individual spike."This technology could possibly be developed into a field-based tool, which could be used by growers and agronomists to assist with their crop management and help minimise losses due to frost," says Professor Able. "The technology as it stands could also be used by plant breeders to make more rapid and more informed selection decisions about the performance of one breeding line over many others."Further R&D is required to enable field deployment of terahertz non-destructive inspection for early frost damage and the research team is looking to develop a working prototype for field tests with other collaborators.
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Agriculture & Food
| 2,020 |
October 2, 2020
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https://www.sciencedaily.com/releases/2020/10/201002141915.htm
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New research sheds light on the reluctance of farmers to adopt new technologies
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Research from the University of Kent's School of Economics sheds new light on a long-standing obstacle to improving agricultural productivity in developing countries: the reluctance of small-scale farmers to adopt modern technologies because of the risks associated with them.
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The paper, published in Science Direct, examined the relationship between attitudes towards risk among small-scale aquafarmers in Ghana and the time they take to adopt new technologies that reduce traditional risks, including; poor weather conditions, aquatic predators and poor hygiene.The researchers conducted a series of psychological experiments with aquafarmers in 30 villages in four regions in southern Ghana to measure their aversion to risk and willingness to take gambles. They also recorded the aquafarmers' adoption of three innovative technologies recently introduced to Ghana: predator-proof floating cages for fish; a nutrient-rich fish feed; and a fast-growing, disease-resistant breed of tilapia fish.Results showed that aversion to traditional production risks accelerated the adoption of all three technologies. However, adoption of floating cages was slower due to the significant upfront financial investment required, making small-scale experimentation with the technology impractical. The study also found that once aquafarmers in a community have started using the cages, the aversion by others to take the risk was further reduced.Based on their findings, the study's authors advocate providing practical information about new agricultural technologies and information about positive returns from their adoption with the help and encouragement of regional extension agents to encourage the adoption of new agricultural technologies by small-scale farmers in developing countries.Dr Adelina Gschwandtner, Senior Lecturer in Economics and Principle Investigator, said: 'These findings may have significant consequences beyond Africa and onto the global agricultural sector. Addressing traditional perceptions with this new understanding of the potential to reduce risk by adopting new ideas, methods, and technologies, may broaden how business ventures are viewed and conducted in the future. This in turn may help agricultural ventures in developing nations become secure and allow them to flourish.'
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Agriculture & Food
| 2,020 |
October 1, 2020
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https://www.sciencedaily.com/releases/2020/10/201001200232.htm
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Bright light bars big-eyed birds from human-altered landscapes
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New research shows the glaring light in human-altered landscapes, such as livestock pastures and crop fields, can act as a barrier to big-eyed birds, potentially contributing to their decline.
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Florida Museum of Natural History researchers found strong links between bird eye size, habitat and foraging technique. Birds that kept to the shade of the forest had larger eyes than those that inhabited the canopy, and birds with relatively small eyes were more numerous in agricultural settings.The findings suggest eye size is an overlooked, but important trait in determining birds' vulnerability to changes in their habitat and could help inform future research on their sensitivity to other bright environments, such as cities."Many bird species literally disappear from highly disturbed, anthropogenic habitats such as agricultural landscapes," said lead author Ian Ausprey, a Ph.D. student in the Florida Museum's Ordway Lab of Ecosystem Conservation and a National Geographic Explorer. "That's probably due to many reasons, but this paper suggests light could be part of that."Despite numerous studies on how light influences the makeup of plant communities, little research has focused on how it drives the ecology of vertebrates. Ausprey said while some of the study's results may seem like "a no-brainer," it is the first to document the relationships between light, eye size and how birds navigate their world.Light is especially key for birds, which use their vision to detect food. Big eyes house more photoreceptors and are a common feature in birds of prey such as owls and raptors, enabling them to resolve images at longer distances and in darker settings.But large eyes can also be susceptible to overexposure and glare in bright environments. Previous research has shown too much light can overwhelm birds, causing them to alter their feeding behavior and diminish their alertness to threats.For four years, Ausprey and fellow University of Florida Ph.D. student Felicity Newell, a study co-author, surveyed birds in the cloud forests of northern Peru, part of the tropical Andes, a global biodiversity hotspot. In these forests, light is structured on a vertical gradient, powerful at the canopy and increasingly weaker as it filters down to the darkest parts of the understory. Gaps in the canopy open up patches of startling brightness, changing light intensity "over infinitesimally small scales," Ausprey said. "You can go from being very dark to very bright within inches."The swift, dramatic changes in the landscape are mirrored in its variety of birds: A difference of 1,000 feet in elevation can uncover a completely distinct avian community.The region is also home to small-scale farms with livestock pastures and vegetable fields, often interspersed with islands of remaining forest. The broad range of ambient light, from the deep, dark forest interior to wide open country, made an ideal model system for measuring birds' use of light, Newell said.Ausprey and Newell measured eye size relative to body size in 240 species that make up the cloud forest bird community of Amazonas, their study region.They found the largest-eyed insect-eating birds were "far-sighted" species, those that nab prey on the wing, such as flycatchers. Eye size in "near-sighted" species that hunt in the dimly lit understory increased the closer to the ground they lived. One such big-eyed species is the rufous-vented tapaculo, Scytalopus femoralis, a bird only found in Peru. Ausprey said the species behaves much like a mouse, scuttling across the forest floor in search of insects in mossy logs and under tree roots.For bird groups that eat fruit, seeds and nectar -- food items that don't require capture -- eye size did not vary based on which part of the forest they inhabited.The researchers also attached tiny light-sensing backpacks to 71 birds representing 15 focal species. The sensors tracked the intensity of light the birds encountered over a period of days, providing a first look at their light "micro-environments."Of these 15 species, the bird that inhabited the darkest environment was the rusty-tinged antpitta, Grallaria przewalskii, another species exclusive to Peru, which spends much of its life walking along the forest floor. The blue-capped tanager, Thraupis cyanocephala, lived in the brightest environments.The researchers also found that eye size was correlated with the abundance of a species in agricultural settings, with smaller-eyed birds being more common, suggesting that birds better adapted to the dark forest understory would struggle to adjust to the flood of light in a field, Ausprey said.Preliminary results from subsequent research suggest these patterns hold at a global scale. The trend might also carry over into urban areas, which "are basically extreme forms of agricultural landscapes in some ways," he said.In fact, the rufous-collared sparrow, Zonotrichia capensis, the bird most commonly found in agricultural fields, is also the most abundant species in Latin American cities, Newell said.The study is the first to emerge from Ausprey and Newell's project, which examined how climate and land use influence cloud forest birds."This study makes excellent use of emerging technologies to answer one of the major questions in ecology -- how do light levels affect the niches of birds and their vulnerability to habitat modification," said Scott Robinson, Ordway Eminent Scholar at the Florida Museum.But the technology required a bit of MacGyvering: The light sensors don't directly transmit data, meaning Ausprey had to figure out a way to get them back. The solution was to superglue a radio tag to the delicate sensor and use a surgical adhesive to attach the packet to a bird's back, sticking long enough to get meaningful information, but detaching after a few days. Ausprey would then clamber over steep ridges and through thick shrubs and bamboo, antenna in hand, to retrieve it.They also had to select the bird species that would cooperate: Large tanagers, toucans and woodcreepers were excluded due to their strong bills and proclivity for aggressive behavior. Even so, three of the expensive, imported sensors wound up chewed and destroyed."When you work with technology in the field, you have to have a strong stomach for tragedy," Ausprey said.Ausprey and Newell expressed thanks to the large team -- about 100 people -- of field assistants, hosts, nature reserve staff and community members that contributed to the project.Ausprey is also a fellow with the UF Biodiversity Institute.
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Agriculture & Food
| 2,020 |
October 1, 2020
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https://www.sciencedaily.com/releases/2020/10/201001090130.htm
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Hand pollination, not agrochemicals, increases cocoa yield and farmer income
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Cocoa is in great demand on the world market, but there are many different ways to increase production. A research team from the University of Göttingen has now investigated the relative importance of the use of pesticides, fertilisers and manual pollination in a well replicated field trial in Indonesian agroforestry systems. The result: an increase in both cocoa yield and farming income was achieved -- not by agrochemicals, but by manual pollination. The study was published in the journal
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Cocoa requires cross-pollination by insects to produce fruit. It is unclear how to encourage natural pollination by tiny midges, flies or wasps: in fact, the true identity of the main pollinators has yet to be discovered. Under natural conditions, more than 90 percent of flowers are not visited by insects and do not develop fruit. These results clearly show that traditional agricultural intensification with agrochemicals is not always the best way forward.Working together with colleagues and students of the Indonesian University of Tadulako of Palu, the scientists found that hand pollination increased the yield of cocoa trees by 161 percent. After deducting the costs of manual pollination, this meant a 69 percent increase in income for small-holder farmers. Using more pesticide and fertiliser did not increase yields."Our results show how agroecological intensification can be successful by promoting biological processes or using innovative techniques such as manual pollination," explains first author Manuel Toledo-Hernández, PhD student in the Department of Agroecology at the University of Göttingen. The work was supervised by Professor Teja Tscharntke, Head of Agroecology, and Professor Thomas C. Wanger, now at Westlake University in China. They add: "Lower harvests due to insufficient pollination have a major effect on many crops in the tropics as well as in temperate latitudes. This should be taken into account much more in future efforts to increase production."
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Agriculture & Food
| 2,020 |
September 30, 2020
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https://www.sciencedaily.com/releases/2020/09/200930194850.htm
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Can organic plant protection products damage crops?
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Protecting crops against pests and diseases is essential to ensure a secure food supply. Around 95 percent of food comes from conventional agriculture, which uses chemical pesticides to keep crops healthy. Increasingly, however, organic pesticides are also being sought as an alternative. Some organic pesticides contain live spores of the fungus Trichoderma, which have the ability to suppress other pathogens. Researchers at the University of Göttingen have now discovered that one Trichoderma species can cause severe rot in cobs of maize (corn).
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The results were published in the journal The massive outbreak of a previously unknown species of Trichoderma on corn cobs in Europe was first detected in Southern Germany in 2018. In affected plants, grey-green spore layers formed on the grains of corn and between the leaves that form the husks of the cobs. In addition, the infested grains germinated prematurely. For this study, the scientists brought maize plants in the greenhouse into contact with Trichoderma by inoculation. They were then able to prove that the dry matter content of the maize cobs is greatly reduced. Annette Pfordt, PhD student at the Department of Crop Sciences of the University of Göttingen and first author of the study, analysed 18 separate Trichoderma strains mainly from maize cobs in Southern Germany and France over two years. She found that some of these strains are highly aggressive with a cob infestation of 95 to 100 percent. By means of molecular genetic analyses, these spores could be assigned to the relatively new species Trichoderma afroharzianum. Within this species of fungus, previously unknown plant-pathogenic strains seem to have evolved which are now responsible for this newly discovered disease affecting maize."The species used in organic plant protection products is a close relative, namely Trichoderma harzianum. Strains of this species were not as aggressive in the study, but in the inoculation experiments they also led to a slight infestation on the cob," says Pfordt. "Although the investigations carried out so far show that the Trichoderma strains used in organic plant protection products differ from the aggressive forms now found, it is also clear that the risks from the use of living microorganisms in plant protection must be thoroughly investigated," adds Professor Andreas von Tiedemann, head of the Department of Plant Pathology and Protection at the University of Göttingen.In vegetable growing, "Trichoderma agents" can be used, for example to control diseases such as Botrytis (grey mould) or Fusarium and to reduce rotting pathogens on the crop products. Various organic products containing Trichoderma are available on the market. They are used almost exclusively in organic farming. Trichoderma species belong to the ascomycetes and are found worldwide in the soil, on plant roots, in decaying plant remains and on wood. They act as decomposers of substrates and as antagonists of other microorganisms. This is the first time that they have been described as pathogens on plants.
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Agriculture & Food
| 2,020 |
September 30, 2020
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https://www.sciencedaily.com/releases/2020/09/200930110124.htm
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Rapeseed instead of soy burgers: Researchers identify a new source of protein for humans
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Rapeseed has the potential to replace soy as the best plant-based source of protein for humans. In a current study, nutrition scientists at the Martin Luther University Halle-Wittenberg (MLU), found that rapeseed protein consumption has comparable beneficial effects on human metabolism as soy protein. The glucose metabolism and satiety were even better. Another advantage: The proteins can be obtained from the by-products of rapeseed oil production. The study was published in the journal
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For a balanced and healthy diet, humans need protein. "It contains essential amino acids which can not be synthesized in the body," says Professor Gabriele Stangl from the Institute of Agricultural and Nutritional Sciences at MLU. Meat and fish are important sources of high-quality proteins. However, certain plants can also provide valuable proteins. "Soy is generally considered the best source of plant protein as it contains a particularly beneficial composition of amino acids," says Stangl.Her team investigated whether rapeseed, which has a comparably beneficial composition of amino acids, could be an alternative to soy. Rapeseed also contains phytochemicals -- chemical compounds produced by plants -- which could have beneficial effects on health, says Stangl. "So far, only a few data on the effect of rapeseed protein intake in humans had been available," adds the scientist. In comparison to soy rapeseed has several other advantages: It is already being cultivated in Europe and the protein-rich by-products of the rapeseed oil production could be used as ingredients for new food products. These by-products are currently used exclusively for animal feed.In a study with 20 participants, the team investigated the effect of ingested rapeseed and soy proteins on human metabolism. Before the interventions the participants were asked to document their diets for a few days. Then they were invited to eat a specifically prepared meal on three separate days: noodles with tomato sauce, that either contained no additional protein, or was enriched with soy or rapeseed protein. After the meal, blood was regularly drawn from the participants over a six-hour period. "By using this study design, we were able to assess the acute metabolic response of each study participants to the dietary treatments." says Stangl.The study showed: "The rapeseed protein induced comparable effects on metabolic parameters and cardiovascular risk factors as soy protein. Rapeseed even produced a slightly more beneficial insulin response in the body," says nutritionist Christin Volk from MLU. Another benefit was that the participants had a longer feeling of satiety after eating the rapeseed protein. "To conclude, rapeseed appears to be a valuable alternative to soy in the human diet," says Volk.The only drawback: "Rapeseed protein, in contrast to soy protein, has a mustard flavour," says Volk. Therefore, rapeseed is more suitable for the production of savoury foods rather than sweet foods, explains the researcher.The work was supported by the Union for Oil and Plant Technology e.V. (UFOP, grant number: 528/181).
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Agriculture & Food
| 2,020 |
September 29, 2020
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https://www.sciencedaily.com/releases/2020/09/200929123555.htm
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Virus turns deadly fungus from foe to friend in plants
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Researchers have discovered that a fungal virus (also called a mycovirus) can convert deadly fungal pathogens into beneficial fungus in rapeseed plants. Once transformed, the fungus boosts the plant's immune system, making the plant healthier and more resistant to diseases. These findings, published on September 29 in the journal
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Rapeseeds that cover farm fields with bright yellow blossoms like a fuzzy golden blanket are the main ingredients of our household cooking staple -- canola oil. Besides serving as vegetable oil, the plants are also a crucial crop for animal feed and biodiesel worldwide. However, rapeseed farms experience significant losses from the fungal pathogen, Sclerotinia sclerotiorum, which causes stem rot, lesions and kills the plants within a few days after infection."The virus we identified can convert the fungus from a deadly pathogen in different plants to an endophytic fungus like a gentle sheep and protect these plants," says the senior author Daohong Jiang, a professor at Huazhong Agricultural University in China. Endophytic organisms live within a plant for at least part of its life cycle without causing diseases, maintaining a symbiotic relationship. "The research is important because we know plants have endophytic fungus, but where did it come from? The fungal virus might have played a role in the evolution of these fungi and that's something we can look into in the future."When infected by the mycovirus, the rapeseed-threatening fungus loses its virulence. Instead of killing the plant, the virus-infected fungus lives peacefully within the plant and even comes with some benefits. Jiang and his colleagues infected the rapeseeds by inoculating seeds with virus-infected fungus fragments and observed a boost in the plants' immune system, an 18 percent increase in weight and more root growth. These plants not only grew bigger and stronger, but it could also resist other diseases."The fungal virus might be a good thing for the fungus because the fungus now recognizes the plant as 'home' instead of killing it," says Jiang. "The virus turned a foe to a friend."In the rapeseed fields, fungus-infected fragments also suppressed stem rot, stimulated plant growth and improved seed yield by 6.9 -- 14.9 percent. Virus-infected fungal pathogens become a novel way to tackle crop diseases by decreasing the virulence of lethal pathogens. Moreover, the researchers found that the fungal virus can be transmitted to other fungal pathogens quickly and efficiently throughout the field, which are ideal traits to develop "plant vaccines.""If you treat the seed with virus-infected fungus, the fungus will grow with the plant throughout its life," says Jiang. "Just like how we vaccinated our kids when they were born, the protection is life-long."Jiang noted that fungal pathogens are a topic that scientists haven't been able to control in agricultural settings. Currently, there are no plants with fungal-pathogen-resistance for these pathogens who attack a wide variety of plants. Fungi cause more than 80 percent of crop disease and destroy one-third of all food crops annually, causing economic loss and impacting global poverty."This fungal disease is also prevalent in the United States. Besides rapeseeds, the fungus also attacks sunflowers, beans and other crops," says Jiang. "Our prevention method and research idea may benefit many others who are engaged in similar work and benefit agricultural production. It has a lot of potentials."This work was financially supported by National Science Foundation of China, the National Key R&D Program, and the China Agriculture Research System.
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Agriculture & Food
| 2,020 |
September 29, 2020
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https://www.sciencedaily.com/releases/2020/09/200929123528.htm
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Plant droplets serve as nutrient-rich food for insects
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Small watery droplets on the edges of blueberry bush leaves are loaded with nutrients for many insects, including bees, wasps and flies, according to a Rutgers-led study, the first of its kind.
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The study, published in the journal "Our study shows for the first time that plant 'guttation' -- fluid from sap secreted at the edges and tips of leaves -- is a nutrient-rich source of food for insects," said senior author Cesar Rodriguez-Saona, a professor and extension specialist in the Department of Entomology in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick.Many insects such as bees, wasps and flies drink the small droplets, which arise on nights with high levels of moisture in soil, and biologists considered them only as a source of water for insects. But the droplets are rich in carbohydrates and contain proteins that are essential for many insect species, according to Rodriguez-Saona.In an experiment in Rutgers blueberry fields, insects with three different feeding lifestyles (an herbivore, a parasitic wasp and a predator) increased their ability to survive and reproduce when they fed on plant guttation droplets during their entire adult lives.The droplets were also present in blueberry fields through the entire season and their presence doubled the abundance of beneficial insects -- parasitic wasps and predators -- that protect plants from pests. As a result, droplets might reduce the many problems caused by pests in crops, including invasive pests. And the researchers suggest that might occur in numerous crops where the droplet phenomenon is common, such as rice, wheat, barley, rye, oats, sorghum, corn, tobacco, tomatoes, strawberries and cucumbers, among others."These findings are important for the conservation of beneficial insects because they can find and feed on droplets when pollen, nectar, hosts or prey are scarce," Rodriguez-Saona said.Overall, the results demonstrate that the droplet phenomenon is highly reliable, compared with other plant-derived food sources such as nectar, and it increases the communities and fitness of insects, the study says.Next steps include investigating the nutritional quality of droplets from other plant species and their fitness benefits for insects, as well as testing whether insecticides remain in droplets after being applied and affect beneficial insects.
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Agriculture & Food
| 2,020 |
September 29, 2020
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https://www.sciencedaily.com/releases/2020/09/200929123427.htm
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New woodlands can help reduce flooding risk within 15 years
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The planting of woodlands in upland areas could play a significant role in preventing the flash flooding which has increasingly affected communities across the world in recent years.
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A new study by the University of Plymouth (UK) has shown that within just 15 years of being planted, native broadleaf trees can have a marked impact on soil's response during extreme weather events.It means the huge quantities of rainwater generated can be more readily absorbed, rather than it simply running over the surface and into rivers where it subsequently causes severe flooding.Writing in This nature-based solution could be extremely timely, given the UK government commitment to planting 30 million trees a year by 2025 and other environmental schemes designed to enhance carbon retention, biodiversity and flood prevention. They caution however, new woodlands will require careful placement if the benefits are to be maximised.There have been a number well-documented extreme rainfall and flooding events in recent years, and they are predicted to increase in both frequency and severity in the coming decades as a consequence of human-induced climate change.In fact, researchers from the University showed in November 2019 that the UK's uplands could see significantly more annual rainfall than is currently being predicted in national climate models.This new research, completed with funding from the Environment Agency as part of the Dartmoor Headwaters Natural Flood Management Project, compared the physical and hydrological properties of surface soils across four flood vulnerable upland headwater catchments in Dartmoor National Park.They showed that in areas where new woodlands have been planted, the ability of soil to absorb water was almost double that of areas with no trees, associated with increases in soil macro-pores and reductions in soil compaction.This means the speed at which rainwater enters rivers during rainfall events is dramatically reduced, which helps lower peak flow.However, the nature of the soil and location of the woodlands is also critical to their success, with steep hillside on the edge of upland areas providing the most effective location for tree plantations to serve as an effective flood prevention tool.The research which was also supported by native woodland charity Moor Trees is the first to measure comparable differences in the water infiltration rates of soils, between native woodland and pasture sites, across multiple upland catchments.Thomas Murphy, who led the research as part of his PhD, said: "Many UK upland areas have a history of soil compaction and the aim of our study was to define how quickly this nature-based solution could affect that. People perhaps think that trees need to be mature in order for them to have beneficial environmental effects. But across our four test sites, we showed they can make significant improvements to soil properties within just 15 years of establishment, meaning it can be a viable option for flood prevention in a relatively modest timeframe."As well as the physical studies, the research involved meetings with resident groups and landowners in flood-vulnerable communities to get their thoughts on the nature of the problems but also to discuss the potential solutions.Dr Paul Lunt, Associate Professor in Environmental Science and the study's senior author, added: "There are a lot of vulnerable upland catchment areas across the UK, where long-term grazing has led to soils becoming damaged. However, by working with farmers and the government's farm woodland grant scheme to exclude livestock on the steeper slopes and replace them with trees, this study has shown that soil damaged by compaction can recover rapidly. This is particularly evident on steeper slopes which are traditionally not so good for farming. So there is an opportunity for a joined-up approach which could benefit the uplands themselves, but also those people living on and around them."
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Agriculture & Food
| 2,020 |
September 23, 2020
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https://www.sciencedaily.com/releases/2020/09/200923135117.htm
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Feeding indoor cats just once a day could improve health
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Got a cat that always seems hungry? New University of Guelph research suggests you might want to reduce -- not increase -- how often you feed them.
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Animal nutrition specialists in U of G's Ontario Veterinary College (OVC) and Ontario Agricultural College (OAC) have found that feeding cats one large meal a day may help control hunger better than feeding them several times a day.The research, published in the journal The results also suggest cutting back feeding frequency could help reduce the risk of obesity by controlling cats' appetite and potentially making them eat less -- an important discovery given that obesity is the most common nutritional problem affecting cats."These findings may surprise the veterinary community and many cat owners who have been told their animals need several small meals a day," said study co-author Prof. Adronie Verbrugghe, a veterinarian with OVC's Department of Clinical Studies, who specializes in companion animal nutrition. "But these results suggest there are benefits to this approach."Previous research has examined the effects of meal frequency on cat behaviour, but this study is the first to use a comprehensive approach analyzing effects on appetite-suppressing hormones, physical activity, energy expenditure and use of energy sources, said co-author Prof. Kate Shoveller, an expert in animal nutrition with U of G's Department of Animal Biosciences."There was no good research to back up the several-meals-a-day approach that many owners hear, and so we wanted to put some real data behind current feeding recommendations to be sure they were right for cats," she said.The study involved eight healthy-weight, indoor cats under the age of five. Each cat was exposed to both feeding regimens and each for a total of three weeks, with the same diet and amount being offered in either one meal or four meals. Some of the cats were fed only in the morning, while the others were fed the same amount in four smaller meals.The cats were equipped with activity monitors on harnesses to measure their voluntary physical activity. Food intake was recorded daily, and body weight was measured weekly. Researchers also measured cat metabolism through breath and blood.Physical activity was higher in cats fed four times a day, but overall energy expenditure was similar between the groups. The weights of the cats in both groups did not change over the study period, no matter which feeding schedule they were on.Cats that ate just once a day had higher post-meal levels of three key appetite-regulating hormones, suggesting they were more satisfied. These cats also showed lower fasting respiratory quotient, suggesting they were burning their fat stores, which is key to maintaining lean body mass.The cats that ate only one meal a day also had a larger increase in blood amino acids, meaning more protein was available to them to build muscle and other important proteins. This is important given that many cats lose muscle mass as they age, a condition known as sarcopenia."Physiologically, it makes sense that feeding only once a day would have benefits," said Shoveller. "When you look at human research, there's pretty consistent evidence that there are positive health outcomes with intermittent fasting and improved satiety."Even big cats in the wild engage in a form of intermittent fasting, the authors note, feasting when they make a kill and fasting before the next one.While their data suggest feeding once a day may be a good way to promote satiation and lean body mass, the researchers would like to do longer studies."This approach is really yet another tool in a veterinarian or a cat owner's toolbox for managing a cat's weight and keeping their animals healthy and happy," said Verbrugghe, who is the Royal Canin Veterinary Diets Endowed Chair in Canine and Feline Clinical Nutrition. "But we always have to look at each individual animal and account for the cat's and owner's lifestyle. So although this approach might be helpful to promote satiety in some cats, it might not help another."The research was funded with support from the Winn Feline Foundation and Simmons Pet Food.
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Agriculture & Food
| 2,020 |
September 22, 2020
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https://www.sciencedaily.com/releases/2020/09/200922112255.htm
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'New' lactic acid bacteria can make African camel milk safe
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A research project headed by the Technical University of Denmark, DTU, has come up with the formula for a freeze-dried starter culture that African camel milk farmers can use to make safe, fermented milk products.
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The majority of the world's camels are located in East Africa, where they are a common dairy animal. Camel milk constitutes upwards of 9% of the total milk production of Africa. The farmers, who milk the animals, sell much of the milk as a fermented product in local markets or roadside stalls.The fermentation process occurs spontaneously as the farmers have no cooling facilities. Given that the level of hygiene is often poor, the milk often also contains disease-causing microorganisms such as E.coli and salmonella, which have the opportunity to multiply in the lukewarm milk.In a research project, researchers from the National Food Institute, Technical University of Denmark, have managed to find a way of making the milk safer. The research was conducted in partnership with the University of Copenhagen, food ingredient producer Chr. Hansen and Haramaya University in Ethiopia. It was partly funded by Denmark's development cooperation programme, DANIDA.The researchers have isolated new strains of lactic acid bacteria from raw camel milk, which can be used in a starter culture that both acidifies the milk and kills off even very large amounts of various disease-causing microorganisms in the milk. To the researchers' knowledge, this is the first time research has shown that these bacteria can be used to make camel milk products safer to consume.The research in the five-year project was conducted partly with the help of a number of students at both the Technical University of Denmark and Haramaya University, who -- over time -- have passed on the baton. In total, ten students from the National Food Institute have spent a semester in Ethiopia, including three Bachelor of Engineering in Food Safety and Quality, who have found the formula for a freeze-dried, quality controlled starter culture based on the bacteria.The trio's experiments have shown that five liters of milk can make enough starter culture to produce half a million liters of safe, fermented camel milk. However, the researchers responsible for the camel milk project recommend that farmers heat-treat the milk to reduce the amount of disease-causing microorganisms in the milk as much as possible before adding the starter culture.The three students-Line Kongeskov Frimann, Laura Pontoppidan and Louise Marie Matzen-found it to be an exciting and stimulating challenge to conduct a project of engineering relevance in a cooperation between two such different universities.Countries like Denmark have an effective health system that can quickly help people who are unfortunate enough to get sick from something they eat or drink. However, in Africa, the health care system is less robust. A foodborne illness that causes diarrhea and vomiting can quickly make a patient dehydrated, and without access to medical care, the illness can be fatal.African researchers estimate that food poisoning kills 137,000 people on the continent annually. For Haramaya University, the project is an important element in the university's work to develop sustainable solutions and increase food safety in Ethiopia.
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Agriculture & Food
| 2,020 |
September 21, 2020
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https://www.sciencedaily.com/releases/2020/09/200921170505.htm
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E. coli bacteria offer path to improving photosynthesis
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Cornell University scientists have engineered a key plant enzyme and introduced it in Escherichia coli bacteria in order to create an optimal experimental environment for studying how to speed up photosynthesis, a holy grail for improving crop yields.
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The method is described in a paper, "Small subunits can determine enzyme kinetics of tobacco Rubisco expressed in Escherichia coli," published in the journal Scientists have known that crop yields would increase if they could accelerate the photosynthesis process, where plants convert carbon dioxide (COResearchers have focused on Rubisco, a slow enzyme that pulls (or fixes) carbon from carbon dioxide to create sucrose. Along with CO"You would like Rubisco to not interact with oxygen and to also work faster," said Maureen Hanson, professor of plant molecular biology at Cornell.In an effort to achieve that, the researchers took Rubisco from tobacco plants and engineered it into The advantage is that since bacteria reproduce so rapidly, researchers may test an altered Rubisco in Initial work by another group that engineered tobacco Rubisco into Led by Myat Lin, a postdoctoral research associate in Hanson's lab and the paper's first author, the researchers were able to break down the process and express a single type of large subunit and a single type of small subunit together in They also discovered that a Rubisco subunit found in trichomes (tiny hairs on plant leaves) worked faster than any of the subunits found in leaf cells."We now have the ability to engineer new versions of plant Rubisco in
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Agriculture & Food
| 2,020 |
September 21, 2020
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https://www.sciencedaily.com/releases/2020/09/200921111629.htm
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Epigenetics linked to genetic differences between domesticated and wild chickens
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Some of the genetic differences that have arisen between domesticated chickens and their wild ancestors, the red junglefowl, are linked to epigenetic changes, according to a new study published in
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Humans started to domesticate certain wild animals, including chickens, several thousand years ago, and change their characteristics through breeding. Domestication led to considerable differences between the domesticated variant and their wild counterpart with respect to behaviour, anatomy and physiology. The largest differences, however, have often arisen relatively recently, during the past few hundred years. Controlled breeding of chickens in the 20th century has led to two different types: laying hens for egg production and broilers that give more meat. A broiler chicken, for example, weighs 6-7 times more than its wild ancestor, the red junglefowl.Not only do modern domesticated chickens differ in their properties from the junglefowl, they also have differences in their genetic material, in a part of the material known as the "epigenetic code." Epigenetic changes can be thought of as small flags that sit on the DNA. They can regulate how the genes are expressed and in this way affect the properties of the organism.The scientists who conducted the new study wondered whether the epigenetic differences between modern domesticated chickens and their wild relatives play a role in driving the rapid change associated with domestication. They investigated this in an advanced cross-breed between the junglefowl and a certain type of domesticated chicken. By crossing these with each other through eight generations, the researchers bred chickens whose genetic material is a random mixture of very short fragments of "domesticated DNA" and "wild DNA." They identified markers in the genetic material to make it possible to see which small fragments came from the junglefowl and which came from the domesticated chicken. They could then study the genetic material at very high resolution.The research group has previously investigated how the expression of certain genes regulates fear behaviour in chickens, which is one of the properties that differ significantly between domesticated chickens and their wild ancestors. The scientists could now measure the most common type of epigenetic marker, DNA methylation, in specimens from exactly the same area of the brain, the hypothalamus. They could then use advanced calculations to see the relationships between the methylation pattern, gene expression, mutations in the genome, and the behavioural properties of the individual animal."We found long, continuous parts of the genetic material where it seemed that the domestication process has caused lower levels of methylation in domesticated chickens than in the wild junglefowl. We also found several 'hotspots' -- parts of the genetic material that regulate the methylation at hundreds of other locations separated by long distances. This is extremely exciting," says Dominic Wright, professor in the Department of Physics, Chemistry and Biology (IFM) at Linköping University. He has led the study, which has now been published in It was initially believed that the methylation of DNA always reduces gene expression, leading to changed properties, but it is now necessary to modify this as research has shown that the true picture is not quite as simple, with methylation both increasing and reducing gene expression. This study shows that, while it is true that methylation influences the expression of certain genes, the inverse can also happen: a mutation in the DNA may influence gene expression, which in turn can regulate methylation."It's extremely interesting that the methylation of specific parts of the genetic material seems to be so carefully controlled. The study shows that the regulation of methylation during the domestication of chickens has been extremely complex," says Dominic Wright.This study has looked at the regulation of methylation in the cross-breeds between wild and domesticated chickens. The scientists are now planning the next step. They are curious about what happens to the methylation pattern when domesticated chickens become feral, and slowly but surely adapt to life in the wild. They have already started to investigate fowl populations on Hawaii, where feral chickens are found that are cross-breeds between junglefowl and domestic chickens without human interference. This will allow them to see how DNA methylation is regulated in wild chickens in natural environments.The research was funded in part by the European Research Council (ERC), the Swedish Research Council and the Carl Trygger Foundation.
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Agriculture & Food
| 2,020 |
September 21, 2020
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https://www.sciencedaily.com/releases/2020/09/200921102536.htm
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Strong markets for cultured meat across meat-reducing Germany and France
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For the first time ever the majority of Germans are limiting their consumption of meat, and many are open to the concept of eating cultured meat, according to a new study.
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The research, published in the journal For their investigation, researchers surveyed 1,000 people in each country asking them a series of questions about their current and intended dietary habits, as well as for their thoughts about cultured meat -- i.e. meat produced without raising and slaughtering animals. This new method of meat production mirrors the biological process of building muscle but does so under controlled conditions.Their analysis found that just 45% of German respondents identified as full meat-eaters, with a further 31% now actively following flexitarian or meat-reduced diets. Meat consumption was more common in France, where 69% identified as full meat-eaters with a further 26% following a flexitarian diet.The research also reveals promising markets for cultured meat in both countries. Although the majority of consumers in France and Germany had still not heard of cultured meat, 44% of French and 58% of Germans respondents said they would be willing to try it, with 37% of French consumers and 56% of Germans willing to buy it themselves.The publication highlights Germany as one of the most vegetarian nations in Europe, noting that per capita meat consumption has been trending down for several decades. Now, for the first time, evidence suggests that German consumers who are not deliberately limiting their meat consumption are in the minority. These patterns are mirrored in France, where almost half of meat-eaters intend to reduce animal consumption in the years ahead although attitudes are harder to shift.The researchers say that the social implications of these findings could be profound. Lead author Christopher Bryant from the Department of Psychology at the University of Bath explained: "We know that the social normality of meat consumption plays a large role in justifying it. Now we are approaching a tipping point where the majority of people are deciding that, primarily for ethical and environmental reasons, we need to move away from eating animals. As eating animals becomes less normal, we will likely see a rise in demand for alternatives like plant-based and cultured meat."Strikingly, they find that cultured meat acceptance is higher among agricultural and meat workers in both France and Germany -- two countries considered as the strongest agricultural powers in the European Union. The team behind the study say this indicates farmers may see cultured meat as a way to address the mass demand for affordable meat, enabling them to move away from intensive industrial production systems and return to more traditional systems, which are more harmonious with environmental and animal welfare outcomes.In the US and in Europe, some of the world biggest meat producers have already backed and partnered with cultured meat innovators including Cargill, Tyson Foods, PHW, the largest German poultry breeder and processor and M-Industry which is part of the Swiss Migros Group.The team found some evidence that pro-cultured meat messages which focus on antibiotic resistance and food safety were more persuasive than those that focused on animal welfare or the environment. Consumers also indicated that they would be more likely to consume cultured meat that is not genetically modified.Study author Nathalie Rolland said, "We can expect to see an increase in interest in novel proteins including cultured meat. First, because we know that increasing familiarity with the concept tends to increase comfort with the idea of eating it. Also, this data was collected before the outbreak of COVID-19, a zoonotic disease which has caused many people to re-examine the role of animals in our food system."Jens Tuider, International Director of ProVeg International, said: "Antimicrobial resistance is a serious public health issue, caused mainly by the widespread use of antibiotics in conventional animal agriculture."Globally, more than 70% of antibiotics are used on animals in intensive farming, dramatically decreasing the efficacy of antibiotics intended for humans. This represents a serious threat to global public health, with a projected death toll from antibiotic-resistant diseases of 10 million per year by 2050. Since cellular agriculture has no need for antibiotics, it could significantly mitigate against this major risk to public health."The research posits that some of the differences observed between France and Germany might best be explained through the lens of culture and tradition, however they note the role that agricultural lobbies continue to play in France. This includes the French decision in 2018 to ban use of meat terms to describe vegetable-based products, such as vegetarian sausages or vegetarian steak. The law is ostensibly to avoid misleading consumers, though the UK's House of Lords disagreed in 2019, saying that these changes could make things more confusing for consumers, not less.Whilst this study focused on France and Germany, lead researcher Chris Bryant argues that the findings could have implications elsewhere. He adds: "Europe still has lower rates of vegetarianism compared to other parts of the world. If these surveys were repeated, we might expect to see even higher rates of meat reduction elsewhere."The normality of meat-eaters being the majority is reversing as more people move towards plant-based diets. The development of better and better alternatives, including cultured meat, only makes this transition easier."
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Agriculture & Food
| 2,020 |
September 21, 2020
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https://www.sciencedaily.com/releases/2020/09/200921091535.htm
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Archaeology uncovers infectious disease spread 4000 years ago
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New bioarchaeology research from a University of Otago PhD candidate has shown how infectious diseases may have spread 4000 years ago, while highlighting the dangers of letting such diseases run rife.
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Yaws -- from the same bacteria species responsible for syphilis (The disease has been eradicated from much of the world but is still prevalent in the Western Pacific, affecting some 30,000 people. A previous global attempt to eradicate this tropical disease failed at the last hurdle in the 1950's and a new attempt was curtailed by the COVID-19 outbreak, University of Otago Department of Anatomy PhD candidate Melandri Vlok says.Ms Vlok's PhD research uses archaeology to shed light on the spread of diseases when different human populations interact for the first time. Her specific interest is in what she calls the "friction zone," where ancient agricultural people met hunter gatherer people.In 2018 she travelled to Vietnam to study skeletal remains from the Man Bac archaeological site. From the Ninh Bình Province in the north of the country, Man Bac was excavated in 2005 and 2007 and has delivered a treasure trove of information for archaeologists thanks to its role during the transition away from foraging to farming in Mainland Southeast Asia.Now housed in Hanoi's Institute of Archaeology those remains are well-studied but had not been analysed for evidence of yaws, Ms Vlok says.Her supervisor at Otago, renowned bioarchaeologist Professor Hallie Buckley, had seen what she thought might be yaws on a photograph of Man Bac remains. Professor Buckley travelled with Ms Vlok and together with a passionate team of experts from Vietnam they confirmed their suspicions, Ms Vlok says. Later, Ms Vlok found a second example of the disease.This was significant, as the Man Bac site dates back 4000 years. Till now, there was no strong evidence for yaws in prehistoric Asia.Ms Vlok's research suggests yaws was introduced to hunter-gatherers in present-day Vietnam by an agricultural population moving south from modern-day China. These hunter-gatherers descended from the first people out of Africa and into Asia who also eventually inhabited New Guinea, the Solomon Islands and Australia.The farmers had been in China for at least 9000 years but it wasn't until around 4000 years ago farming was introduced to Southeast Asia. It is possible this movement of people brought diseases, including yaws, at the same time.Ms Vlok says the length of time the disease has existed in the region is relevant when addressing how hard it has been to eradicate."This matters, because knowing more about this disease and its evolution, it changes how we understand the relationship people have with it. It helps us understand why it's so difficult to eradicate. If it's been with us thousands of years it has probably developed to fit very well with humans."This year's COVID-19 pandemic has focused people's attention on infectious diseases, and there are lessons to be learned from the past, Ms Vlok says."Archaeology like this is the only way to document how long a disease has been with us and been adapting to us. We understand with COVID-19 today how fantastic that disease is at adapting to humans. And Treponema has been with us for so much longer."So, this shows us what happens when we don't take action with these diseases. It's a lesson of what infectious diseases can do to a population if you let them spread widely. It highlights the need to intervene, because sometimes these diseases are so good at adapting to us, at spreading between us."
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Agriculture & Food
| 2,020 |
September 18, 2020
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https://www.sciencedaily.com/releases/2020/09/200918104255.htm
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Glyphosate residue in manure fertilizer decrease strawberry and meadow fescue growth
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A new study finds that glyphosate residue in manure fertilizer decrease the growth of strawberry and meadow fescue as well as runner production of strawberry.
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Earlier experiments with Japanese quails showed how glyphosate residue in poultry feed accumulated in quail manure. In these experiments, half of the quails were fed with glyphosate-contaminated feed while the control group were fed with organic feed free from glyphosate residues. This allowed testing whether glyphosate residues in poultry manure affect crop plants if the manure is used as a fertilizer."We established an experimental field where we planted both strawberry and meadow fescue. These plants were fertilized with bedding material containing excrements from quails raised on feed containing glyphosate residue and organic feed free of the residue," tells Senior Researcher Anne Muola from the Biodiversity Unit of the University of Turku, Finland.The growth and reproduction of strawberry and meadow fescue were monitored throughout one growing season. High amount of glyphosate residue (158 mg/kg) decreased the growth of both studied crop plants and runner production of strawberry even if the amount of glyphosate in the soil decreased fast during the growing season.In addition, the manure fertilizer containing glyphosate residue was found to have indirect effects. Larger meadow fescues were producing more inflorescences and herbivorous insects preferred larger strawberries."Our results support earlier studies which have found that already very small glyphosate residue (< 1 mg/kg) in soil affect the germination and growth of crop plants. Our results also show that glyphosate residue accumulated in poultry excrements can inhibit the growth-promoting effects of manure when applied as fertilizer," explains Docent Marjo Helander from the Department of Biology.Glyphosate-based herbicides are the most frequently used herbicides globally. Many GMO crops are so called "glyphosate ready" meaning that they are resistant to glyphosate. This allows agricultural practices where glyphosate is applied in considerable amounts which increases the likelihood of its residue ending up in animal feed."For instance, the cultivation of GM soy is not allowed in the EU. Still, soy is an excellent energy and protein source and it is imported from outside the EU to be used as a component in animal feed. The glyphosate residues in feed are then accumulated in poultry excrement," says Marjo Helander and continues:"Poultry manure is rich in essential nutrients and organic compounds, and thus, to increase the sustainability of poultry industry, regulations suggest that poultry manure should be used as an organic fertilizer. However, this can lead into a situation where glyphosate can be unintentionally spread to fields or gardens via organic fertilizer, counteracting its ability to promote plant growth."
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Agriculture & Food
| 2,020 |
September 18, 2020
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https://www.sciencedaily.com/releases/2020/09/200918083712.htm
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Shift in West African wildmeat trade suggests erosion of cultural taboos
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New research by the University of Kent's Durrell Institute of Conservation and Ecology (DICE) has demonstrated a clear fluctuation in the trade of wildmeat in and around the High Niger National Park in Guinea, West Africa.
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Conservationists found a significant increase in the trading of species that forage on crops including the green monkey (Chlorocebus sabaeus) and warthog (Phacochoerus africanus), in comparison with earlier data, in spite of religious taboos against the killing and consumption of monkeys and wild pigs by Muslims in the region. These species are increasingly being killed to protect crops and farmers can gain economically from their sale, providing an additional incentive for killing. The consumption of wild pigs is prohibited by Islam, yet a marked increase in the number of carcasses recorded in rural areas from 2011 to 2017 has suggested an erosion in the religious taboo.The research team led by Dr Tatyana Humle (DICE) alongside colleagues from Beijing Forestry University, China, and the Higher Institute of Agronomy and Veterinary of Faranah, Guinea, drew conclusions after examining the wildmeat trade in three rural markets in the Park and in the nearest urban centre, Faranah, by collecting market survey data during August-November 2017, and comparing it with data from the same period in the 1990's, 2001 and 2011.Mammals, most notably small sized species, now dominate the wildmeat trade around High Niger National Park. Further findings indicate a marked increase in the number of carcasses and biomass offered for sale from 2001 onwards in rural areas, whereas in Faranah there were no notable differences with data gathered in 1994. Therefore, urban demand does not appear to be driving the wildmeat trade in this region. Instead, the wildmeat trade in rural areas could perhaps be linked to an increase in human population and limited access to alternative sources of animal protein.Dr Humle said: 'This study highlights that despite the local reduction in urban demand for wildmeat, pressures on wildlife in the Park remain. The prominence of crop-protection is increasingly being recognised for driving the wildmeat trade across rural West Africa, yet there is a need to better understand the motivations behind hunting and supply and demand dynamics. There is wider scope to investigate and improve the balance between local farmers' livelihoods and biodiversity conservation.'
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Agriculture & Food
| 2,020 |
September 17, 2020
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https://www.sciencedaily.com/releases/2020/09/200917181152.htm
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Scientists 'scent train' honeybees to boost sunflowers' seed production
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If you want a dog to hunt something down, it helps to let them sniff an item to pick up the scent. Now, researchers reporting in
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"We show that it's possible to condition honeybees to a rewarded odor inside the colony, and this experience modifies the bees' odor-guided behaviors later," says Walter Farina of Universidad de Buenos Aires, Argentina. "The most surprising and relevant result is that the foraging preferences for the target crop are so prolonged and intensive that it promoted significant increases in the crop yields."Farina's team had previously shown that honeybees could establish stable and long-term memory related to food scents inside the nest. They also knew that those in-hive memories could influence the bees' choices about which plants to visit later.To raise bees with a memory that would support later foraging on sunflowers, the researchers first developed a simple synthetic odorant mixture that the bees associated with the natural floral scent of sunflowers. Next, they fed the hives with scented food. They found that those early experiences and memories of the scent of sunflower influenced the bees' later foraging preferences, as inferred by decoding their waggle dances.The bees' training led them to visit sunflowers more. Those trained bees also brought more sunflower pollen back to the hive. This increased visitation and foraging on sunflowers also boosted the flowers' production of seeds by 29 to 57 percent."Through this procedure, it is possible to bias honeybee foraging activity and increase yields significantly," Farina says. "In other words, pollination services might be improved in pollinator-dependent crops by using simple mimic odors as part of a precision pollination strategy."The researchers say they are now studying other pollinator-dependent crops, including almonds, pears, and apples. Ultimately, their goal is to develop an array of new odor mimics to improve pollination efficiency and productivity of many important agricultural crops.
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Agriculture & Food
| 2,020 |
September 17, 2020
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https://www.sciencedaily.com/releases/2020/09/200917105403.htm
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Plant nutrient delivery breakthrough
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When most people think of fungi, the thoughts are usually not good, turning to something that does damage more than those that are actually helpful.
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Yet, fungi play a critical role in the growth and development of plant life and have for millions of years. Scientists have known for a long time that arbuscular mycorrhizal (AM) fungi that live in harmony with about 90% of land plants and play a key role in their root systems, are responsible for carrying needed phosphate to plants to help growth.Now, however, thanks to a discovery by a team of scientists from Texas Tech University's Institute of Genomics for Crop Abiotic Stress Tolerance (IGCAST) in the Department of Plaint and Soil Science, and the Nanjing Agricultural University's State Key Laboratory of crop Genetics and Germplasm Enhancement, that symbiotic role may go even further.That research team, which included professor Guohua Xu, Prof. Aiqun Chen and Dr. Huimin Feng from Nanjing Agricultural University and, Luis Herrera-Estrella, the President's Distinguished Professor of Plant Genomics and director of IGCAST, and assistant professor Damar López-Arredondo, discovered that AM fungi also acted as a supplier of nitrogen to the plant, the protein (NPF4.5) responsible for transporting nitrates from the fungi to the plant, and that this symbiotic nitrate pathway and the function of the protein are present in crops such as rice, and probably most other plant species.The results from the paper, "Functional analysis of the OsNPF4.5 nitrate transporter reveals a conserved mycorrhizal pathway of nitrogen acquisition in plants," were recently published by Xu highlighted their finding that the fungi colonization efficiency, promotion of plant growth and nutrient uptake were maintained and even enhanced at high nitrogen supply levels, which is opposite to the high phosphate suppressed colonization, indicating the general contribution of mycorrhizal route to improving N use efficiency at varied N presence.This discovery could lead to groundbreaking agricultural practices that allow for a reduction in the amount of nitrogen fertilizer required for crop production, which will help reduce production costs and benefit the environment by reducing agrochemical use."In our study, we showed the nitrate transporter is contained in many plant species and that it is activated by the mycorrhizal association in maize, sorghum and several other plant species," Herrera-Estrella said. "Based on our data, we propose that nitrate transport takes place in many if not most plant species, and that the protein plays a key role in the process."Hundreds of millions of years ago, when plants moved from aquatic origins and began taking over land masses, their lack of a strong root system became a hinderance in obtaining water and nutrients. Herrera-Estrella said fossilized evidence showed that, early in in the evolutionary process, land plants developed the relationship with mycorrhizal fungi, which helped improve the fitness of host plants by facilitating mineral nutrition and water absorption and by increasing tolerance to biotic and abiotic stresses.Herrera-Estrella pointed out, though, that past research has discovered that the symbiotic relationship between plants and AM fungi is most active in soil with low phosphate availability and suppressed in soil with high levels of available nutrients. That means cultivated crops that are highly fertilized see a severely reduced or completely suppressed impact from mycorrhiza.The goal of the research was to determine whether mycorrhiza could provide other nutrients such as nitrogen to the plant. Indirect evidence has shown the fungi could supply the plant with ammonium (NH4+) as a nitrogen source, but that it is quickly converted into nitrate (NO3-) by the microbes in the aerobic soil. That means that under most soil conditions, nitrate is the dominant form of N supplied to the plant.In order to test for nitrate transfer ability, the researchers used nitrogen isotopes to determine the capacity of the fungi to take nitrate ad deliver it to the plant for intake. Researchers also identified the gene (NPF4.5) specifically activated in rice roots when joined by mycorrhizal fungi and were able to identify the role of this gene in nitrate delivery by producing rice mutants that did not have this transporting gene."We found that when the gene is inactivated, the amount of nitrate that the plant can get from the fungi is drastically reduced," Dr. Chen said. "Thus, we functionally confirmed that NPF4.5 was the important protein in the transport of nitrogen from the fungi to the plant. We also used plant transformation to generate the rice plants that enrich NPF4.5 proteins in the absence of the mycorrhiza. We found that these transgenic plants can produce more biomass and show higher nitrogen uptake efficiency than normal plants when grown in nitrate contained medium, which has a great potential for use in agriculture."Researchers estimate that rice containing the mycorrhizal relationship between plant and fungi could receive more than 40% of its nitrogen due to the mycorrhizal pathway and that the specific nitrate transporter gene, NPF4.5, accounted for approximately 45% of the mycorrhizal nitrate uptake.López-Arredondo said the next steps in the project will be to test the transgenic plants under field conditions and deeply understand the mechanisms that specifically activate the NPF4.5 nitrate transporter gene when the plant joins with the fungi, as well as discovering the chemical signals the fungi send to the plant to specifically activate this and other nutrient transporter genes probably required for this interaction.Herrera-Estrella, an Emeritus Professor of Cinvestav in Mexico and member of the US National Academy of Sciences stated "This is an interesting and productive collaboration between Texas Tech and the Nanjing Agricultural University," "This type of international collaboration can rally boost the advancement of science."
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Agriculture & Food
| 2,020 |
September 17, 2020
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https://www.sciencedaily.com/releases/2020/09/200917105352.htm
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Secret of plant dietary fiber structure revealed
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The secret of how fibre shapes the structure of plant cell walls has been revealed, with potentially wide-ranging applications ranging from nutrition and health to agriculture.
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Researchers from The University of Queensland and KTH Royal Institute of Technology in Sweden have uncovered the mechanics of how plant cell walls balance the strength and rigidity provided by cellulose with its ability to stretch and compress.UQ Director of the Centre for Nutrition and Food Sciences Professor Mike Gidley said the team identified that a family of cell wall polymers -- hemicelluloses -- played a critical role in balancing the need for rigidity with the flexibility to bend without breaking."This discovery is important for understanding dietary fibre properties in nutrition, but also for applications in medicine, agriculture and a range of other industries," Professor Gidley said."Plants don't have a skeleton, and their structures can range from soft, floppy grasses to the majestic architecture of a Eucalypt tree, with the key differences lying in their cell wall fibre structures."The diversity of plant structures results from the three core building blocks of plant fibre -- cellulose, hemicellulose and lignins -- in the plant cell walls."Lignins provide the water-proofing in woody fibre and cellulose is the rigid scaffolding material in almost all plant types, but the mechanical function of hemicellulose was something of a mystery," Professor Gidley said.Professor Gidley and Dr Deirdre Mikkelsen, in collaboration with Dr Francisco Vilaplana at KTH's Wallenberg Wood Science Centre, experimented with two major components of hemicellulose -- with dramatic effect."We tested the properties of cellulose when adding different proportions of the two components, and found that 'mannans' improved compression while 'xylans' drastically increase its stretchiness," Dr Mikkelsen said."We generated modified cellulose material in the laboratory that could be stretched to twice its resting length -- the equivalent to watching a wet sheet of paper being stretched to double its length without tearing."The team said its discovery had many applications, including in wound care and in the texture of plant foods."This information is also of interest for gut microbiome research in understanding more about how plant cells walls, or fibre, break down in the gut," Professor Gidley said."Complex plant fibre is already processed for low value applications, but high value materials are usually made from pure (bacterial) cellulose."Our work creates the basis for a new cellulose chemistry in which xylans and mannans are added to make composites with useful properties."This means new possibilities for developing better, environmentally-sustainable plant-based materials, as well as selecting natural plant fibres with desirable properties in agriculture and food."
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Agriculture & Food
| 2,020 |
September 17, 2020
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https://www.sciencedaily.com/releases/2020/09/200917105347.htm
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Research shows potential of gene editing in barley
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An international team of plant scientists have shown the potential to rapidly improve the quality of barley grain through a genetic tool known as CRISPR or gene editing.
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Published in The Joint senior author Associate Professor Matthew Tucker, Deputy Director of the Waite Research Institute, says: "Barley grain is comparatively rich in beta-glucan, a source of fermentable dietary fibre that protects against various human health conditions. However, crops with a low content of this compound are preferred for brewing and distilling."The research has given us further insight into key genes responsible for barley grain composition and, by using CRISPR gene editing, plant breeders will have the potential to accelerate plant breeding and deliver new crop varieties that are best suited to their target markets."This work was carried out by Dr Guillermo Garcia-Gimenez during his PhD at the James Hutton Institute and the University of Adelaide. It is the first published use of the CRISPR technique to influence barley grain quality in Australia and Scotland.Dr Garcia-Gimenez says: "We used what's called a reverse genetics approach, using CRISPR to generate changes in members of the gene superfamily responsible for making beta-glucan. The results led to specific differences in grain quality, composition and content of beta-glucan."We hope this work will contribute to creating awareness about the potential of this technique and we look forward to trialling the new plants in field conditions."Associate Professor Tucker says: "This study has brought real immediate benefit in terms of understanding how gene editing can help improve the quality of barley crops. And it's part of our overall ongoing efforts to apply the latest genetic techniques to deliver improvements for the food and feed industries."Professor Matthew Gilliham, Director of the Waite Research institute, says: "Barley is Australia's second most important cereal crop behind wheat, contributing around $3 billion to the economy. Despite recent market fluctuations, this discovery is important and opens the door to significant economic impact for breeders and growers."The Waite Research Institute, in partnership with The International Barley Hub, is showing again that research in this area can yield great returns on investment in the basic understanding of barley."
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Agriculture & Food
| 2,020 |
September 16, 2020
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https://www.sciencedaily.com/releases/2020/09/200916090530.htm
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Choosing the right cover crop to protect the soil
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Farmers around the world are keen to protect their most important asset: their soil. The soil supports and enriches their crops. But the relatively thin layer of topsoil can readily wash away into streams, carrying unwanted nutrients with it.
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Enter cover crops. Cover crops are inedible plants grown during the off-season. Their roots help keep soil in place, preventing erosion. Cover crops can even absorb excess nutrients like nitrogen to keep them from polluting streams. Farmers are increasingly interested in using cover crops to help their farms. But with a dizzying array of plants to choose from and complex crop rotations, making the right choice is no easy feat."I believe cover crops are a very important tool for both retaining soil and keeping nutrients on the farm," says María Villamil, a researcher at the University of Illinois and a member of the American Society of Agronomy. "In the Midwest, we are very lucky to have high fertility soils, making us big providers of food worldwide. The protection of our soils is critical."To help farmers in Illinois choose the right cover crop, Villamil and her team decided to test several potential cover crops. They planted different cover crops between the common Midwestern rotation of corn and soybeans. The researchers worked closely with farmers to choose which cover crops to test."They wanted to test different cover crops, especially ones that don't generate extra work in the spring and others that will not compete with the corn for resources," says Villamil.Farmers preferred growing cereal rye as a cover crop before soybeans were planted. The rye captured the nitrogen remaining in the soil after the previous year's corn crop season. But, when farmers were planning to grow corn, they preferred using a vetch cover crop. Vetch is a legume crop, which means it can provide nitrogen for the corn to use later in the season. Vetch also uses less water than cereal rye, which means the corn crop will not need to work as hard to compete for limited water resources.Villamil's team set up experimental plots at six locations around the state. Toward the end of the growing season for corn or soybeans, researchers walked through the crop fields to spread cover crop seeds among the plants. This mimics seeding by airplane. Aerial seeding has been a popular idea to plant cover crops in a timely manner over existing crops in fields. The cover crops they tested included spring oats, red clover, annual ryegrass and radishes, among others.Then the researchers tracked how well the cover crops grew, how soil properties changed over time, and the yield of future food crops.Surprisingly, the cover crops didn't have a big effect on the soil. "There was not much improvement of the soil properties with using a cover crop, except for maybe the rotation using the annual ryegrass," says Villamil.The biggest reason most of the cover crops didn't affect the soil very much is that most of them died over the winter. That's largely because of the weather. Midwestern states like Illinois are subject to potentially harsh winters, especially in the northern part of the state. The broadcast seeding the researchers did also meant that the seeds simply sat on top of the soil. That meant the cover crops had a harder time germinating than if the seeds had been buried in the ground.But cover crops that die over winter can be a good thing. Dead cover crops mean farmers will have less work killing them in the spring. But they're also less effective at protecting the soil or absorbing nutrients.Annual ryegrass and cereal rye, both grasses, largely survived the winter, as did hairy vetch, a legume like soybeans. The grasses slightly reduced future corn yields. That's probably because they compete with corn for water in the spring."The yields of soybeans were not affected at all. Soybeans grow very well with cover crops, so we need to take advantage of that," says Villamil.The team also tested how tilling the fields affected the soil and yields, but saw only modest effects."The lesson is that wringing benefits from cover crops requires a bigger commitment to using them to protect the soil," says Villamil. "That means choosing cover crops that can survive the winter, grow a lot in the spring, and hold onto soil that whole time. Some cover crops might slightly decrease future crop yields, but in the long-term, protecting our soil is worth it.""If we want to see benefits from cover crops, we need to focus on managing our cropping systems for cover crops, giving them room to grow, and using them strategically following corn crops, or silage corn or even wheat, if we are lucky to have this crop in the rotation" she says. "Our main goal when using cover crops should be protecting the soil and leaving the soil nutrients in place."
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Agriculture & Food
| 2,020 |
September 16, 2020
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https://www.sciencedaily.com/releases/2020/09/200916090526.htm
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Slower growing chickens experience higher welfare, commercial scale study finds
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Slower growing broiler chickens are healthier and have more fun than conventional breeds of birds, new evidence from an independent commercial scale farm trial has shown. The study carried out by researchers from FAI Farms, the University of Bristol and The Norwegian University of Life Sciences, is published today [16 September], in
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The majority of broilers produced for consumption are so called conventional, fast-growing breeds. This study is the first to highlight the welfare differences between fast and slower growing broilers in a commercial setting utilising a comprehensive suite of positive and negative welfare indictors. The authors conclude that, while there are benefits of providing chickens with more space -- by slightly lowering the animal density, changing to a slower growing breed results in much better health and more positive experiences for these birds.Annie Rayner, FAI's lead researcher, said: "Broilers are motivated to perform a range of positive behaviours. These positive behaviours create positive experiences, resulting in enjoyment or pleasure. Displaying positive behaviours improves an animal's quality of life. Our seminal study found slow growing birds to have better health and perform more positive behaviours than conventional fast growing broilers. A shift away from fast-growing breeds would provide the most significant improvement for the lives of the 142 million chickens produced in Europe every week."Dr Siobhan Mullan, Senior Research Fellow in Animal Welfare at the Bristol Vet School, added: "This first independent commercial scale trial provides robust evidence of the health and welfare benefits of slower growing breeds of chicken. We hope that it will help to drive changes in supply chains and large companies to bring about real improvements to chicken welfare."The NGO-backed European Chicken Commitment (ECC) has attracted widespread attention from commercial broiler production with several major brands already having signed up -- including KFC, Nestle, M&S and Nando's. This study set out to interrogate the commercial welfare implications of two critical aspects of the commitment -- a move to slower growing breeds and lowering the stocking density.The commercial-scale farm trial explored a comprehensive suite of positive and negative welfare indicators in four production systems varying in stocking density and breed. One slower growing breed (the slowest) was stocked at a planned maximum density of 30 kg/m2, a second slower growing breed at planned densities of 30 kg/m2 and 34 kg/m2, and the welfare outcomes were compared to those of a standard fast-growing breed stocked at 34kg/m2.At the lower density, the slowest growing breed was found to have slightly better welfare than the other slower growing breed -- as indicated by lower mortality, fewer rejections at processing and better walking ability. Differences in welfare of the slower growing breed stocked at two densities were small. However, prominent differences were found between the standard fast-growing birds stocked at 34kg/m2 and birds in the three other systems. The standard birds experienced poorer health as indicated by higher levels of mortality, hock burn and pododermatitis as well as greater rejections at processing. Furthermore, the conventional birds showed less perching on enrichment bales as well as fewer positive 'play' and 'exploration' behaviours.Professor Ruth Newberry and Dr Judit Vas at The Norwegian University of Life Sciences Faculty of Biosciences point to the importance of including indicators of positive experiences in animal welfare studies. "Until recently, play was hardly ever mentioned in studies of chickens. We found that, when you walk through a commercial flock, you just have to turn around and look behind you to see chickens frolicking in your footsteps. This was especially the case in the slower growing flocks."
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Agriculture & Food
| 2,020 |
September 16, 2020
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https://www.sciencedaily.com/releases/2020/09/200916131055.htm
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Reforestation can only partially restore tropical soils
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Tropical forest soils play a crucial role in providing vital ecosystem functions. They provide nutrients for plants, store carbon and regulate greenhouse gases, as well as storing and filtering water, and protection against erosion. Scientists at the University of Göttingen and the University of Minnesota in the USA have investigated how the properties and ecosystem functions of tropical soils change when forests are cut down, and whether reforestation can reverse such soil degradation. The results of the study are published in the journal
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For the analysis, the team collected data from 130 different studies from 35 tropical countries. Based on this huge amount of data with more than 10,000 individual observations, they compiled the most comprehensive study to date on how soils are affected by deforestation in the tropics and how they recovered after reforestation. The study draws important conclusions about tropical land use. "Various aspects of soil degradation after deforestation, such as carbon and nutrient losses, acidification and compaction, have been investigated in separate studies for decades. Our analyses bring all this research together and show for the first time the extent and dynamic nature of soil degradation," says first author Professor Edzo Veldkamp, who leads Soil Science of Tropical and Subtropical Ecosystems at the University of Göttingen.In the study, the team shows that changes in soil properties depend on the original soil fertility and intensity of cultivation. Dr Marife Corre, the study's senior author, says: "Our analyses show that the degradation of soil properties is still significantly detectable even decades after deforestation. For example, soils that have been used for crops more than 25 years after deforestation continue to lose carbon in the form of COThe good news is that reforestation can partially restore some of the degraded soil properties. However, these positive changes are mainly limited to the topsoil, and the resulting soil properties under reforestation still differ significantly from the original forest soils. Veldkamp says: "The deeper soil layers react much more slowly to reforestation than the topsoil." Land-use management practices that increase organic matter in the soil and include trees (for example, agroforestry systems) can slow down soil degradation. Smallholders are more likely to plant trees and invest in improved nutrient management if they have secure land tenure, access to markets to sell their goods, and access to knowledge and finance to make their farms profitable. Effective policies that can create such conditions are an important step towards more sustainable land uses in the tropics.
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Agriculture & Food
| 2,020 |
September 15, 2020
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https://www.sciencedaily.com/releases/2020/09/200915090123.htm
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Successful improvement of the catalytic activity of photosynthetic CO2 fixing enzyme Rubisco
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A research group consisting of Associate Professor FUKAYAMA Hiroshi (Kobe University, Graduate School of Agricultural Science) and Professor MATSUMURA Hiroyoshi (Ritsumeikan University) et al. have succeeded in greatly increasing the catalytic activity of Rubisco (*1), the enzyme which fixes carbon from CO
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In the future, it is hoped that increasing the photosynthetic ability of agricultural crops will lead to increased yields.These results were published in the international scientific journal Growth speed in plants is mainly determined by photosynthetic ability. Thus improving photosynthesis in agricultural crops can increase their yield. In photosynthesis, Rubisco is an enzyme that acts as the initial catalyst for the reaction which turns CORubisco's catalytic activity varies depending on the type of plant. Most major crops, such as rice, wheat and soybean are CThe catalytic rate is low in CRubisco is made up of two types of protein- large subunits (RbcL) and small subunits (RbcS). The sequence of the amino acids in RbcS varies greatly between species. This team has been focusing on conducting research into RbcS. They genetically modified rice (a CIn this CSS line (sorghum RbcS transferred/rice RbcS knocked out), the rice RbcS was completely replaced by sorghum RbcS, producing hybrid Rubisco. This approximately doubled the catalytic rate to that which is equivalent to CSubsequently, the researchers conducted x-ray crystallography (*2) in order to illuminate the mechanism by which sorghum RbcS increases Rubisco's catalytic activity. RbcL is present in Rubisco's catalytic site. Near this catalytic site, there is a structure called RbcS βC. The 102 amino acid found in βC is isoleucine in rice and leucine in sorghum. Leucine has smaller molecules than isoleucine. Therefore, it is thought that in sorghum RbcS the gaps between amino acid molecules become bigger, making the reaction site more pliable and thus increasing catalytic activity. Although further research is necessary to prove this, it is believed to be a previously unproposed ground-breaking theory for Rubisco research.The CSS line produced in this study demonstrated high photosynthetic ability, however crop yield was not improved. Hopefully, it will be possible to vastly improve plant growth and productivity through appropriate control of Rubisco levels.The current research used the CIt is thought that the 102 amino acid is an important determinant of the catalytic activity. Further research is being carried out to investigate this; for example by replacing only the amino acid at the 102 site with another amino acid and producing Rubisco.
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Agriculture & Food
| 2,020 |
September 14, 2020
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https://www.sciencedaily.com/releases/2020/09/200914160748.htm
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Gene-edited livestock 'surrogate sires' successfully made fertile
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For the first time, scientists have created pigs, goats and cattle that can serve as viable "surrogate sires," male animals that produce sperm carrying only the genetic traits of donor animals.
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The advance, published in the "With this technology, we can get better dissemination of desirable traits and improve the efficiency of food production. This can have a major impact on addressing food insecurity around the world," said Jon Oatley, a reproductive biologist with WSU's College of Veterinary Medicine. "If we can tackle this genetically, then that means less water, less feed and fewer antibiotics we have to put into the animals."A research team led by Oatley used the gene-editing tool, CRISPR-Cas9, to knock out a gene specific to male fertility in the animal embryos that would be raised to become surrogate sires. The male animals were then born sterile but began producing sperm after researchers transplanted stem cells from donor animals into their testes. The sperm the surrogate sires produced held only the genetic material of the selected donor animals. The gene-editing process employed in this study seeks to bring about changes within an animal species that could occur naturally, such as infertility.The study is the result of six years of collaborative work among researchers at WSU, Utah State University, University of Maryland and the Roslin Institute at the University of Edinburgh in the U.K.The researchers used CRISPR-Cas9 to produce mice, pigs, goats and cattle that lacked a gene called NANOS2 which is specific to male fertility. The male animals grew up sterile but otherwise healthy, so when they received transplanted sperm-producing stem cells from other animals, they started producing sperm derived from the donor's cells.The surrogate sires were confirmed to have active donor sperm. The surrogate mice fathered healthy offspring who carried the genes of the donor mice. The larger animals have not been bred yet. Oatley's lab is refining the stem cell transplantation process before taking that next step.This study provides a powerful proof of concept, said Professor Bruce Whitelaw of the Roslin Institute."This shows the world that this technology is real. It can be used," said Whitelaw. "We now have to go in and work out how best to use it productively to help feed our growing population."Scientists have been searching for a way to create surrogate sires for decades to overcome the limitations of selective breeding and artificial insemination, tools which require either animal proximity or strict control of their movement -- and in many cases, both.Artificial insemination is common in dairy cattle who are often confined so their reproductive behavior is relatively easy to control, but the procedure is rarely used with beef cattle who need to roam freely to feed. For pigs, the procedure still requires the animals be nearby as pig sperm does not survive freezing well. In goats, artificial insemination is quite challenging and could require a surgical procedure.The surrogate sire technology could solve those problems since the surrogates deliver the donor genetic material the natural way -- through normal reproduction. This enables ranchers and herders to let their animals interact normally on the range or field. Donors and surrogates do not need to be near each other since either frozen donor sperm or the surrogate animal itself can be shipped to different places. In addition, female NANOS2 knockout animals remain fertile -- since the gene only affects male fertility -- and could be bred to efficiently generate sterile males to be used as surrogate sires.This technology has great potential to help food supply in places in the developing world, where herders still have to rely on selective breeding to improve their stock, said Irina Polejaeva, a professor at Utah State University."Goats are the number one source of protein in a lot of developing countries," Polejaeva said. "This technology could allow faster dissemination of specific traits in goats, whether it's disease resistance, greater heat tolerance or better meat quality."The surrogate sires technology could also open up a new option for genetic conservation of endangered species, whose dwindling numbers leave animal communities isolated from each other, limiting their genetic diversity.None of the benefits of surrogate sires can be realized, however, without changes in the current landscape of government regulations and public perception.Even when the technology is advanced enough for commercialization, gene-edited surrogate sires could not be used in the food chain anywhere in the world under current regulations, even though their offspring would not be gene-edited. This is due in part to the misperceptions that gene editing is the same as the controversial gene manipulation, Oatley said. Gene editing involves making changes within a species that could occur naturally. It does not combine DNA from different species.Oatley realizes there is a lot of work to do outside of the lab and recently joined the National Task Force on Gene Editing in Livestock to bring together researchers, industry representatives, bioethicists and policymakers to find a path forward for the technology."Even if all science is finished, the speed at which this can be put into action in livestock production anywhere in the world is going to be influenced by societal acceptance and federal policy," said Oatley. "By working with policymakers and the public, we can help to provide information assuring the public that this science does not carry the risks that other methods do."This study was supported by the USDA National Institute of Food and Agriculture, WSU's Functional Genomics Initiative and Genus plc. The Roslin Institute receives strategic investment funding from the Biotechnology and Biological Sciences Research Council, as part of U.K. Research and Innovation, and it is part of the University of Edinburgh's Royal (Dick) School of Veterinary Studies. At Utah State University, this study was supported by the Utah Agricultural Experiment Station.
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Agriculture & Food
| 2,020 |
September 14, 2020
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https://www.sciencedaily.com/releases/2020/09/200914115905.htm
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Global study reveals time running out for many soils, but conservation measures can help
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A major new international study has provided a first worldwide insight into how soil erosion may be affecting the longevity of our soils.
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The study, led by Lancaster University in collaboration with researchers from Chang'an University in China, and KU Leuven in Belgium, brought together soil erosion data from around the globe, spanning 255 locations across 38 countries on six continents.This data was used to calculate how long it would take for the top 30 cm of soil to erode at each location -- the soil lifespan. The top layer of soil is often rich in nutrients and organic matter, making it important for growing food, fibres, feed and fuel. Soil erosion is a serious threat to global sustainability, endangering food security, driving desertification and biodiversity loss, and degrading ecosystemsThe study included soils that are conventionally farmed, as well as those managed using soil conservation techniques, to find out how changes to land use and management practices can extend the lifespans of soils.Researchers found more than 90 per cent of the conventionally farmed soils in the study were thinning, and 16 per cent had lifespans of less than a century. These rapidly thinning soils were found all over the world, including countries such as Australia, China, the UK, and the USA."Our soils are critically important and we rely on them in many ways, not least to grow our food," says lead author Dr Dan Evans of Lancaster University. "There have been many headlines in recent years suggesting that the world's topsoil could be gone in 60 years, but these claims have not been supported with evidence. This study provides the first evidence-backed, globally relevant estimates of soil lifespans."Our study shows that soil erosion is a critical threat to global soil sustainability, and we need urgent action to prevent further rapid loss of soils and their delivery of vital ecosystem services."However, there are causes for optimism. In the data, soils managed with conservation strategies tended to have longer lifespans, and in some cases these practices promoted soil thickening. Only seven per cent of soil under conservation management had lifespans shorter than a century, and nearly half exceeded 5,000 years.Co-author, Professor Jess Davies, also of Lancaster University, said: "Whilst 16 per cent of soils with lifespans shorter than 100 years is a more optimistic estimate than '60 harvests left', soil is a precious resource and we can't afford to lose that much over a human lifetime."But importantly what our study also shows is that we have the tools and practices to make a difference -- employing the appropriate conservation methods in the right place can really help protect and enhance our soil resource and the future of food and farming."Converting arable land to forest was found to be the best way to lengthen soil lifespans. However, other approaches that allow farming to continue, such as cover cropping, where plants are grown between cropping seasons to protect the soil, were also shown to be highly effective. The ploughing of land along contours rather than down slope, and hillslope terracing were similarly suggested as beneficial for lengthening soil lifespans.Professor John Quinton, of Lancaster University and co-author of the study, said: "It is clear that we have a conservation toolbox that can slow erosion and even grow soil. Action is needed to promote the adoption of these measures so that we can protect and enhance our soil resource for future generations."
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Agriculture & Food
| 2,020 |
September 14, 2020
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https://www.sciencedaily.com/releases/2020/09/200914095857.htm
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Some but not all US metro areas could grow all needed food locally, estimates study
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Some but not all U.S. metro areas could grow all the food they need locally, according to a new study estimating the degree to which the American food supply could be localized based on population, geography, and diet.
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The modeling study, led by Christian Peters at the Gerald J. and Dorothy R. Friedman School of Nutrition Science and PolicyGerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University, is published today in The model estimates whether 378 metropolitan areas could meet their food needs from local agricultural land located within 250 kilometers (155 miles). Local potential was estimated based on seven different diets, including the current typical American diet.The results suggest:* Large portions of the population along the Eastern Seaboard and the southwest corner of the U.S. would have the least potential for localization.* Surplus land existed under all diet scenarios, raising questions about the best use of land for meeting health, environmental, and economic goals."Not everyone lives near enough agricultural land to have an entirely local or even regional food supply. Most cities along the Eastern Seaboard and in the southwest corner of the U.S. could not meet their food needs locally, even if every available acre of agricultural land was used for local food production. Yet, many cities in the rest of the country are surrounded by ample land to support local and regional food systems," said Peters, senior author and associate professor at the Friedman School, whose research focuses on sustainability science.Peters and his team also modeled seven different diets to estimate whether dietary changes could make a difference in the potential to produce sufficient food for a metro area. The diets ranged from the current typical American diet, which is high in meat, to vegan. Reducing animal products in the diet increased the potential to produce all food locally, up to a point. Diets with less than half the current consumption of meat supported similar levels of localization potential, whether omnivore or vegetarian. Consumption of meat (beef, pork, chicken and turkey) for the baseline typical American diet was estimated at roughly five ounces per day."There would be different ways to do it. Imagine, if we cut back to fewer than two and a half ounces per day by serving smaller portions of meat and replacing some meat-centric entrees with plant-based alternatives, like lentils, beans and nuts. More diverse sources of protein could open new possibilities for local food. Nutrition research tells us that there could be some health benefits, too," said corresponding author Julie Kurtz, who was a master's degree student at the Friedman School at the time of the study.Under all the diet scenarios, the model projected the United States having a surplus of land for meeting domestic food needs. In the current American agricultural system, some farmland is used for biofuels and export crops. The researchers point out that if metro centers focused on eating locally, many agricultural areas would face new questions about local land use priorities."It would be important to make sure policies for supporting local or regional food production benefit conservation and create opportunities for farmers to adopt more sustainable practices. Policies should also recognize the capacity of the natural resources in a given locale or region -- and consider the supply chain, including capacity for food processing and storage," Peters said.Economic efficiency for food production was beyond the scope of the analysis. Also, the study is based on current conditions and does not consider how future climate change may affect future agricultural potential.
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Agriculture & Food
| 2,020 |
September 14, 2020
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https://www.sciencedaily.com/releases/2020/09/200911110756.htm
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How plants ensure regular seed spacing
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An international team of researchers led by biologists from Heinrich Heine University Düsseldorf (HHU) has examined how seed formation is coordinated with fruit growth. In the latest edition of the journal
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If you open up a pea pod, you will find that all of the peas inside are the same size and the same distance apart. The same is true of princess beans, runner beans and soybeans as well as various other peas and beans, and it also applies to non-pulses. This is surprising because both the seed size and number and the pod size differ substantially from one variety to the next.A team of researchers based in Germany, Australia, Japan, the USA and Italy under the supervision of Prof. Dr. Rüdiger Simon from HHU's Institute of Developmental Genetics has analysed the genetic mechanisms behind this phenomenon. The team used different wild varieties of thale cress to examine the genetic processes taking place behind the initiation of ovules -- the primordia from which seeds emerge after fertilisation -- and the growth of the pod. These wild varieties are sourced from different locations. Thale cress or Arabidopsis thaliana is a model plant used in biology. Prof. Simon commented: "The individual seeds compete with each other for nutrients. To ensure that each seed gets an equal supply and can develop well, it is important that the seeds are spread as evenly as possible at equal distances in the pod."There is considerable variation in fruit size and seed number even amongst the different wild varieties of Arabidopsis thaliana. However, the researchers also discovered a uniform genetic mechanism that controls seed position in the pod regardless of environmental factors such as temperature.The team established that seed formation is controlled by several signalling pathways at precisely defined positions. These signalling pathways are activated by small secreted proteins from the EPFL family. These peptides are detected on the cell surface by receptors from the ERECTA family. One of the peptides, EPFL2, is formed between the developing ovules, where it adjusts the spacing between the seeds. Where this peptide is not present, the researchers found irregular spacing -- meaning that adjacent seeds compete more for nutrients -- or even ovule twinning, which generally results in neither ovule developing fully. EPFL2 and a very closely related peptide, EPFL9, also control fruit development. As a result, seed formation is closely linked to pod growth.Dr. Nozomi Kawamoto, the first author of the study, highlighted another aspect: "The same signalling substances and receptors that we have identified as being responsible for relative pod size and seed spacing are also in charge of the spacing of leaf stomata and the microstructure of serrated leaves." A plant uses the stomata to regulate the exchange of gases with its environment. Dr. Kawamoto is carrying out post-doctoral research at Prof. Simon's Institute as part of the Cluster of Excellence on Plant Sciences CEPLAS in Düsseldorf.
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Agriculture & Food
| 2,020 |
September 14, 2020
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https://www.sciencedaily.com/releases/2020/09/200914095859.htm
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Food mechanics recipe to serve up healthy food that lasts
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QUT researchers are working to design faster, cheaper, and better ways to store food.
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Published in journal Lead investigator Dr Charith Rathnayaka is a computational scientist from QUT's Faculty of Science and Engineering investigating the physics, mathematics, and biology of agricultural cell structures to improve food production."By developing the computational model, it is possible to estimate how the cells are being damaged when they are being processed for preservation, storage or packaging," Dr Rathnayaka said."This innovation has the potential to influence the future of food drying processes globally in terms of reducing cost, optimising food processing, energy conservation and increasing dried food shelf life."Key findings: -Dr Rathnayaka said the findings of this study could lead to better designs for industrial drying of fruits, vegetables, or any other plant biological material.As an example, he described the process by using fresh fruit such as apples which were simultaneously dried and imaged and then compared against the predictions from the simulations.The experimental data revealed microscopic tissues of the apple and the differences between fresh conditions and extremely dried conditions, with imagery featured in journal Soft Matter. (pics)"One specific reason for using apple as representative plant-food material was due to the abundant availability of experimental findings," he said."It showed that by controlling the processing conditions such as temperature, pressure, humidity and processing speed, it is possible to control the damage on apple cells to extract the best nutritional value."He said the results also showed that at extreme dryness levels, the cells naturally get damaged even without processing."Due to the high pressure in the cells at fresh conditions, they are highly vulnerable to higher forces that take place during processing such as cutting, packing, or extruding," he said."This provides valuable insights for not only processing apples but many other comparable fruits and vegetables."Dr Rathnayaka said the study's findings have implications for further research into food processing under drought conditions.He said there is a need to find innovative ways to investigate harvesting and processing produce under extreme climatic conditions."Currently there is a research gap in accurately evaluating and predicting drought and heat resistance of plant-food tissues," he said."The COVID-19 pandemic has placed even more of an emphasis on the ever-growing importance of plant-food security and more efficient ways to quantify and predict the performance of agricultural produce during droughts."
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Agriculture & Food
| 2,020 |
September 11, 2020
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https://www.sciencedaily.com/releases/2020/09/200911110747.htm
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Taste buds may play role in fostering obesity in offspring
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Cornell food scientists show in animal studies that a mother's high-fat diet may lead to more sweet-taste receptors and a greater attraction to unhealthy food in their offspring -- resulting in poor feeding behavior, obesity in adulthood.
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The researchers' findings were published July 31 in Maternal exposure to a high-fat diet during the perinatal period -- before the animal gets pregnant -- appears to induce physical, detectable changes in the taste buds for offspring, said senior author Robin Dando, associate professor of food science in the College of Agriculture and Life Sciences."We see this is something actually happening in the taste buds themselves," Dando said. "Adult progeny, fed such a diet, have more sweet-taste receptors inside their taste buds than in the control group, whose mothers ate a steady, healthy diet."Five weeks before mating, female mice were fed high-caloric, high-fat meals; other mice were also fed the high-fat diet from their pregnancy through lactation.The progeny, weaned after the lactation period, ate healthy, high-quality laboratory chow. When the offspring became adults, the mice received their first taste of the high-fat diet."Up until then, the animals showed no difference between themselves and the control group," Dando said. "But as soon as the offspring of the moms who consumed the unhealthy diet had access to it, they loved it and they over-consumed it."The offspring only encountered a high-fat diet by way of the maternal environment."If a mother has an unhealthy diet where she consumes a lot of calories through high-fat and sugary products," Dando said, "the offspring are going to have a predisposition for liking the unhealthy diet. The origin of this is not only the changes the brain, but there are other physical changes happening within the taste buds."As Dando stressed, these results are in mice, but obesity in humans combined with an environmental component, the heritability is between 40% to 70%. "Obesity in the offspring is strongly predicted by the metabolic state of the parents," he said.While the specific mechanism remains unclear, Dando said, the results introduce the concept of "taste" to the list of metabolic alterations arising from fetal programming."Our research adds to the evidence that the taste bud plays a role in the etiology of obesity," he said. "From a public health standpoint, improving our knowledge of prenatal and early postnatal factors that program obesity in offspring may provide insight into therapeutic targets to combat the obesity epidemic -- a disease easier to prevent than to cure."
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Agriculture & Food
| 2,020 |
September 10, 2020
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https://www.sciencedaily.com/releases/2020/09/200910120123.htm
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Diamondback moth uses plant defense substances as oviposition cues
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A research team from the Nanjing Agricultural University in Nanjing, China, and the Max Planck Institute for Chemical Ecology in Jena, Germany, showed that isothiocyanates produced by cruciferous plants to fend off pests serve as oviposition cues. The plant defense substances serve as odor signals for females of the diamondback moth to lay their eggs on these plants. The scientists identified two olfactory receptors whose sole function is to detect these defense substances and to guide the moths to the ideal oviposition sites. They uncovered the molecular mechanism that explains why some insects that specialize in feeding on certain host plants are attracted by substances that are supposed to keep pests away.
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Cruciferous plants, such as cabbage, rape (canola), mustard and horseradish, produce glucosinolates. Upon mechanical damage of the plant tissues, e.g. caused by a chewing insect, glucosinolates are hydrolyzed by the endogenous plant enzyme myrosinase. This leads to the formation of a variety of toxic breakdown products, mainly isothiocyanates, to defend themselves against voracious insects. This defense mechanism is very effective against most herbivores. The diamondback moth Plutella xylostella, however, has evolved mechanisms of its own to outwit this defense: It is able to feed successfully on plants of the cabbage family and make use of the plants for its own reproductive purposes."We wanted to know whether the moths use isothiocyanates as odor cues to locate their host plants. In fact, behavioral experiments showed that three isothiocyanates are key signals for female moths to locate and lay eggs on cruciferous plants," says study leader Shuang-Lin Dong from Nanjing Agricultural University.The main scientific question was, what are the molecular mechanisms on which female Plutella xylostella moths base their choice of the oviposition site? The researchers therefore analyzed, which olfactory receptors were highly expressed in female moths, and studied the function of these receptors in the frog oocytes. "With this method, we were able to investigate which odors an individual receptor was responding to. We showed that two receptors, OR35 and OR49, responded to the three isothiocyanates that we had previously identified as being crucial for oviposition," says Markus Knaden from the Max Planck Institute in Jena. These two receptors did not respond to any other plant-related odors or to the sex pheromones of the moths. Presumably, OR35 and OR49 evolved to detect precisely those egg-laying signals. "We were surprised that even two receptors are specifically tuned to the isothiocyanates. The two receptors, however, detect the isothiocyanates with different sensitivities. We hypothesize that the more sensitive receptor could make sure that female moths locate plants from a distance, while the other may help to provide a more accurate detection of the isothiocyanate concentration. This will give the female moths more information about the substrate on which they will lay their eggs," says Shuang-Lin Dong.The researchers used the CRISPR-Cas9 genetic scissors to knock out the genes encoding the two receptors in moths. This method is used to test the function of a specific gene. For egg-laying assays, they used plants of the thale cress Arabidopsis thaliana, a model plant that belongs to the cruciferous plant family. Some of these plants were unmodified and produced isothiocyanates that were attractive to the moths, whereas the others were mutants that were unable to produce isothiocyanates. When one of the two receptors was inactivated, the moths laid considerably fewer eggs on the isothiocyanates-emitting plants. When both receptors were knocked out, the moths were unable to discriminate between unmodified Arabidopsis plants and the mutant plants.In the course of evolution, plants have developed various strategies to defend themselves against herbivores. A crucial part of plant-insect interaction is chemical communication. "In most cases, it is useful for a plant to communicate to potential herbivores that its defense system is already activated. However, there will be always someone who misuses the communication for its own benefit, like in our case the diamondback moth, which uses a plant defense signal as an attractant and lays eggs and spreads on this plant," says Markus Knaden. Finding out how these "cheaters" outwit plant defenses and even use these defenses for their own purposes could help improve the control of global crop pests (such as the diamondback moth): "Our results offer various approaches to control this pest: On the one hand, we could use the identified isothiocyanates or other attractive substances as attractants to trap these pests. On the other hand, we could try to develop chemical agents to interrupt or block the perception of the isothiocyanates and thus interfere with the females' location of their host plants," summarizes Shuang-Lin Dong.Further investigations are planned to study whether other insects that attack cruciferous plants also use special receptors to detect isothiocyanates and to locate the plants for oviposition. The results may provide information on the extent to which the perception of these odors by specialized receptors is also conserved in other species.
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Agriculture & Food
| 2,020 |
September 10, 2020
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https://www.sciencedaily.com/releases/2020/09/200910110834.htm
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Bumblebees benefit from faba bean cultivation
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About one third of the payments received by farmers are linked to specific "greening measures" to promote biodiversity. The cultivation of nitrogen-fixing legumes is very popular. However, these measures have been criticized because the benefits for biodiversity are unclear. Now a team from the University of Göttingen, the Julius Kühn Institute and the Thuenen Institute in Braunschweig has investigated whether the cultivation of the faba bean (Vicia faba -- also known as the broad bean or fava bean) can support wild bees. It turns out that bumblebees benefit from the cultivation of faba beans, while all other wild bees depend on the presence of semi-natural habitats. The results of the study have been published in the
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The researchers recorded wild bees in various German agricultural landscapes for the study. In one half of the landscapes, conventionally farmed faba beans were cultivated; in the other half there were no bean fields. "The nectar of the faba bean is hidden deep in the flowers and is only easily accessible to larger bees with long tongues, such as bumblebees. We therefore wanted to investigate how groups of wild bees, which differ in their external appearance, react to the cultivation of faba beans and whether they can benefit from it," says first author Nicole Beyer from the Functional Agrobiodiversity Group at the University of Göttingen. The study results show that there were more than twice as many bumblebees in the faba bean landscapes than in the landscapes without beans. In contrast, the cultivation of beans did not affect other wild bees. However, these other wild bees benefited from a high proportion of semi-natural habitats."Our research clearly showed that certain bee species can be supported by similar measures in farmed areas. But the benefits depend strongly on the characteristics of the crop and pollinator. In order to encourage the widest possible range of species, we propose a combination of measures: the cultivation of various flowering arable crops such as faba beans and the promotion or preservation of semi-natural habitats with a diverse range of flowers and nesting sites for many other wild bees," concludes Professor Catrin Westphal, Head of Functional Agrobiodiversity at the University of Göttingen.
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Agriculture & Food
| 2,020 |
September 10, 2020
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https://www.sciencedaily.com/releases/2020/09/200910110822.htm
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How chemical diversity in plants facilitates plant-animal interactions
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We aren't the only beings who enjoy feasting on tasty fruits like apples, berries, peaches, and oranges. Species like bats, monkeys, bears, birds, and even fish consume fruits -- and plants count on them to do so.
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Wildlife disperse their seeds by eating the fruit and defecating the seed elsewhere, thus carrying the fruit farther away and spreading the next generation of that plant. But attracting wildlife might also mean attracting harmful organisms, like some species of fungi.Plants walk a fine line between attraction and repulsion, and to do this, they evolved to become complex chemical factories. Chemical ecologists at the Whitehead Lab at Virginia Tech are working to uncover why plants have such diverse chemicals and to determine the functions of these chemicals in plant-microbe and plant-animal interactions."There is still so much we don't know about the chemical compounds plants use to mediate these complicated interactions. As we continue to lose global biodiversity, we are also losing chemical diversity and the chance for discovery," said Lauren Maynard, a Ph.D. candidate in the Department of Biological Sciences within the College of Science.Piper sancti-felicis is a neotropical shrub related to Piper nigrum, which produces black peppercorn. Although P. sancti-felicis isn't as economically important as its peppery cousin, it fulfills an important ecological role as one of the first plants to colonize a recently disturbed area. It also serves as an important food source for wildlife, especially bats and birds.At La Selva Biological Station in Costa Rica, Maynard and a team of international ecologists worked to better understand the evolutionary ecology of P. sancti-felicis. Their findings were recently published in By analyzing the samples, the team discovered 10 previously undocumented alkenylphenol compounds in P. sancti-felicis. Alkenylphenols are rare in the plant kingdom, as they have been reported only in four plant families.The alkenylphenol compounds were not distributed evenly across the plant, though. Maynard found that fruit pulp had the highest concentrations and diversity of alkenylphenol compounds, while leaves and seeds had only a few compounds at detectable levels. Later, a pattern emerged: Levels of alkenylphenol were highest as flowers developed into unripe pulp, but then decreased as the pulp ripened.When Maynard and her collaborators tested alkenylphenols with different species of fruit fungi, they found that the alkenylphenols had antifungal properties. But those same compounds also made the fruits less tasty to bats, which are the plant's main seed dispersers.This is a delicate balance: high levels of alkenylphenols protected the fruit from harmful fungi as it developed, but when it ripened, alkenylphenol levels dwindled so that bats would be interested in eating it."Many fungal pathogens attack ripe fruits and can make fruits unattractive to dispersers, or worse, completely destroy the seeds. Our study suggests that these toxins represent a trade-off in fruits: They do deter some potential beneficial partners, but the benefits they provide in terms of protecting seeds outweigh those costs," said Susan Whitehead, an assistant professor in the Department of Biological Sciences.This study is the first to document an ecological role of alkenylphenols. Chemical interactions in the plant kingdom are not easy to see, but they play a crucial role in balancing trade-offs in various interactions. In the case of P. sancti-felicis, alkenylphenols help the plant walk the fine line between appealing to seed dispersers and repelling harmful fungi."Finding the nonlinear pattern of alkenylphenol investment across fruit development was really exciting. It suggests that the main function of the compounds is defense," said Maynard, who is also an Interfaces of Global Change Fellow in the Global Change Center, housed in the Fralin Life Sciences Institute.This discovery helps researchers understand the nuances of tropical forest ecology and how chemical diversity in plants helps maintain that delicate balance. Plant chemical defenses have mostly been studied in leaves of plants, so this new discovery furthers scientists' understanding of how and why these compounds are crucial in fruits. And because fruits are the vehicle for seed dispersal, these chemicals play a significant ecological role."This study advanced our understanding of how tropical forests work by bringing together scientists and expertise from multiple fields of study: plant ecology, animal behavior, chemistry, and microbiology," said Whitehead, who is also an affiliated faculty member of the Global Change Center and the Fralin Life Sciences Institute.The Whitehead Lab has several ongoing projects focused on plant chemistry and seed dispersal at La Selva Biological Station. Since international travel is not possible at the moment, the team hopes to resume their research when it is safe to do so.
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Agriculture & Food
| 2,020 |
September 9, 2020
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https://www.sciencedaily.com/releases/2020/09/200909124014.htm
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Caffeine shot delivers wake-up call on antifungal drug resistance
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The management of fungal infections in plants and humans could be transformed by a breakthrough in understanding how fungi develop resistance to drugs.
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It was previously thought that only mutations in a fungi's DNA would result in antifungal drug resistance. Current diagnostic techniques rely on sequencing all of a fungi's DNA to find such mutations.Scientists from the University of Edinburgh have discovered that fungi can develop drug resistance without changes to their DNA -- their genetic code.The new research, published in Each year fungal diseases affect billions of people globally, causing an estimated 1.6 million deaths.Infections resistant to treatment are a growing problem, particularly in patients with weakened immune systems such as those with HIV. Few effective antifungal drugs exist.Overuse of agricultural fungicides is also leading to increasing resistance in soil borne fungi. Fungal disease results in the loss of up to a third of the world's food crops annually.A team of scientists from the University of Edinburgh's Wellcome Centre for Cell Biology studied the emergence of resistance in a yeast, Schizosaccharomyces pombe, by treating it with caffeine to mimic the activity of antifungal drugs.The team discovered that the resulting resistant yeast had alterations in special chemical tags that affect how their DNA is organized. Some genes became packed into structures known as heterochromatin, which silences or inactivates underlying genes, causing resistance as a result of this epigenetic change.This discovery could pave the way for new therapies to treat resistant infections by modifying existing epigenetic drugs or developing new drugs that interfere with fungal heterochromatin.Improved fungicides to treat food crops could limit agricultural losses and also reduce the number of resistant fungal strains in the environment that continue to fuel increased infections in humans.Professor Robin Allshire, who led the study at the Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, said: "Our team is excited about the possible implications that these findings may have for understanding how plant, animal and human fungal pathogens develop resistance to the very limited number of available and effective antifungal drug treatments."Sito Torres-Garcia, Darwin Trust of Edinburgh funded PhD student and first author of the paper, said: "Our study shows for the first time that fungal cells can develop drug resistance by altering how their DNA is packaged, rather than altering their DNA sequence."The study was funded by Wellcome and The Darwin Trust of Edinburgh.
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Agriculture & Food
| 2,020 |
September 9, 2020
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https://www.sciencedaily.com/releases/2020/09/200909114803.htm
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Making dog food more delectable by analyzing aromas
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Dogs aren't known for being picky about their food, eating the same kibble day after day with relish. However, owners of pampered pooches want their pets to have the best possible culinary experience, especially for those rare finicky canines. Now, researchers reporting results from a pilot study in ACS'
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For dogs, palatability depends on a food's appearance, odor, taste and texture -- just as it does for people. Previous studies have suggested that odor is especially important for dogs. Some scientists have identified volatile compounds in dog food, but not much is known about how specific aroma compounds influence how readily the dog eats the food. Maoshen Chen and colleagues wanted to identify the key aroma compounds in six dog foods and correlate the compounds with dogs' intake of the foods.The researchers began by feeding six adult beagles one of six foods for one hour each and determining how much the dogs ate. The intake of three of the foods was two to four times higher than that of the other three foods. Using mass spectrometry, the researchers found that 12 volatile aroma molecules were correlated, either positively or negatively, with the beagles' intake of the six foods. Then, the researchers added each aroma compound to an odorless food and gave the beagles a choice between food containing one of the compounds and the odorless food itself. From these experiments, the team determined that the dogs preferred food containing (
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Agriculture & Food
| 2,020 |
September 9, 2020
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https://www.sciencedaily.com/releases/2020/09/200909100259.htm
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Bacteria are in key role for successful recirculating aquaculture farming
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Aquaculture is one of the fastest growing food production sectors globally. Due to continuous growth, ecologically, economically and socially sustainable sites for aquaculture are already in use, which has caused a need for new fish farming techniques. Recirculating aquaculture systems, technology that recycles and saves water, has expanded in recent years. The technology has not yet achieved economic viability, mainly due to high investment and operating costs. In addition, the operation and management of bioreactors has been one of the biggest issues, which microbiological processes were studied by M.Sc. Jani Pulkkinen in his dissertation.
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Bioreactors utilize bacteria in the water purification process. In bioreactors, toxic ammonia excreted by fish is microbially converted to more harmless nitrate in the nitrification process."Although bioreactors are designed for the decomposition of nitrogen compounds, the main functions of bacteria in bioreactors were the decomposition of carbohydrates, amino acids and fats. The impact of bioreactors as a whole on water quality is thus much more diverse than previously thought. A diverse and stable bacterial community can maintain good water quality, not only in terms of nitrogen compounds, but also in organic matter," Jani Pulkkinen says.Different types of bioreactors can trap solids from water or affect the gas balance, but different bioreactors also have different nitrification efficiencies, i.e. how fast ammonia can be converted to nitrate."The sizing and selection of bioreactor type should be done taking into account the characteristics of the entire water treatment system," says Pulkkinen.The biological and mechanical solids removal capacity of bioreactors can compensate the properties of the rest of the water treatment system. By optimizing the entire water treatment system, the best possible water quality can be maintained for the well-being and growth of the fish, which enables cost-effective and environmentally friendly aquaculture.The dissertation consisted of four publications using modern molecular microbiology methods. All studies were conducted in the experimental recirculating aquaculture facilities of the Natural Resources Institute Finland (Luke) Laukaa fish farm. The dissertation has been funded by Luke, the European Union and the Ministry of Agriculture and Forestry from the European Maritime and Fisheries Fund.The doctoral dissertation has been published in the JYU Dissertations series, number 242, University of Jyväskylä, Jyväskylä 2020, ISSN 2489-9003, ISBN 978-951-39-8197-6.
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Agriculture & Food
| 2,020 |
September 8, 2020
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https://www.sciencedaily.com/releases/2020/09/200908170533.htm
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A new method may make tomatoes safer to eat
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When vegetable farmers harvest crops, they often rely on postharvest washing to reduce any foodborne pathogens, but a new University of Georgia study shows promise in reducing these pathogens -- as well as lowering labor costs -- by applying sanitizers to produce while it is still in the fields.
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Initially researchers were going to study the use of a nonchlorine-based sanitizer made of two food additives approved by the U.S. Food and Drug Administration -- levulinic acid and sodium dodecyl sulfate -- as a postharvest wash solution. However, at the suggestion of a producer involved in the study -- Bill Brim of Lewis Taylor Farms in Tifton, Georgia -- they designed the study using the solution in a preharvest spray, said Tong Zhao, associate research scientist with the Center for Food Safety on the UGA Griffin campus.While producers commonly use chlorine-based disinfectants -- including chlorine gas, sodium hypochlorite, calcium hypochlorite and chlorine dioxide -- to treat produce postharvest, the preharvest application of bactericides is not a common practice, Zhao said.Building on previous studies of levulinic acid and sodium dodecyl sulfate that showed the combination substantially reduces both In the field studies, the spray treatment significantly reduced the total bacterial population on the surface of tomatoes, determining that this preharvest treatment is a practical, labor-cost effective and environmentally friendly approach for the control and reduction of foodborne pathogens. The study was recently published in the journal "This combination of chemicals had never been used for preharvest treatment," said Zhao, who studied the combination 10 years ago as an alternative to chlorine treatment as a postharvest wash. "Free chlorine is easily neutralized by organic material, which is a big problem when you are using it to reduce pathogens."In both laboratory and field tests, tomato plants were sprayed all over with a solution containing five strains of To test the effectiveness of the chemicals in the lab as a preventative and as a treatment, tomato plants were separated into three equal groups then sprayed with the bacteria solution. The first group was treated with acidified chlorine as the positive control, the second with a treatment solution containing levulinic acid and sodium dodecyl sulfate as the test group, and the third treated with tap water only as the negative control.For the three plots used for farm application testing, the positive and negative control groups were treated the same way, and a commercial product -- Fit-L -- was diluted according to the manufacturer's description and used as the treatment solution. Before treatment studies on the farm, two concentrations of the treatment solution were tested for safety on tomato seedlings in the greenhouse.Results from the studies showed that the application, used either as a preventative or as a treatment, significantly reduced the populations of inoculated Shiga toxin-producing "I have to express appreciation to the Georgia Fruit and Vegetable Association for funding this and other research that is of benefit to agricultural producers in the state," Zhao said.In addition to being effective and affordable, preharvest treatment with levulinic acid and sodium dodecyl sulfate to reduce pathogens also saves labor costs for producers who need workers to perform postharvest washing and drying of produce before packaging."This method can easily be adopted using equipment that most farms are already using," Zhao said. "Preharvest treatment is very effective, efficient and easy considering the amount of labor needed for postharvest washing."
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Agriculture & Food
| 2,020 |
September 8, 2020
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https://www.sciencedaily.com/releases/2020/09/200908162119.htm
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Plant Science Research Network releases decadal vision 2020-2030
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Plant science research has tremendous potential to address pressing global issues including climate change, food insecurity and sustainability. However, without sustained investment in plant science, the necessary research to generate innovative discoveries that solve these urgent problems is at risk.
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On September 1, the Plant Science Research Network (PSRN) released its Plant Science Decadal Vision 2020-2030: Reimagining the Potential of Plants for a Healthy and Sustainable Future, a report that outlines bold, innovative solutions to guide investments and research in plant science over the next 10 years.The PSRN calls on its community to unite around the Decadal Vision's priorities and to inspire their government representatives and fellow community members."The Decadal Vision is a community-wide vision that is a powerful tool for communication and advocacy," said David Stern, President of the Boyce Thompson Institute and corresponding author. "After all, the public should be the ultimate beneficiary of the vision."The Decadal Vision grew out of Plant Summit 2019, a conference held February 10-13, 2019, at Biosphere 2 in Arizona."Fifty diverse participants -- including scientists, industry representatives, educators and advocates -- discussed the future of research, training and infrastructure," says Stern, who is also an adjunct professor of plant biology in Cornell University's College of Agriculture and Life Sciences. "From that meeting, the writing team developed the Decadal Vision as a rallying cry for all plant scientists to unite around a common vision, inspire new collaborations to pursue interdisciplinary research goals, and implement new paradigms for professional development that will catalyze a more diverse, inclusive, and equitable future."The Decadal Vision recognizes the intersection of human and scientific elements and demands integrated implementation of strategies to advance research, people and technology. The vision is presented through eight specific and interdisciplinary goals, each with an accompanying action plan.Four research goals are presented: Harness plants for planetary resilience; Advance technology for diversity-driven sustainable plant production systems; Develop 21st-century applications of plant science to improve nutrition, health, and well-being; and Launch the "Transparent Plant," an interactive tool to discern mechanisms and solve urgent and vexing problems.When it comes to agriculture, "Increasing food production may not be the solution," explains co-author Ole Wendroth, professor of soil science at the University of Kentucky. "Food needs to be produced more sustainably, and plant science plays an important role in this for the future. Farmers that I have worked with are very willing to take this bold step as long as they can produce a safe farm income."The two goals emphasizing our people are: Reimagine the workplace to nurture adaptive and diverse scientists; and Build capacity and interest to engage with plant science."What I like about the Decadal Vision is that equity and justice were part of the vision right from the beginning, and not just tacked on at the end," says co-author Madelaine Bartlett, an associate professor of biology at the University of Massachusetts Amherst. "Everyone should have the same opportunities that I have had, but that is simply not the case right now. It is hard work, but it can be done and it must be done."Bartlett adds that collaborations among people from many scientific disciplines is the new normal, and the PSRN has strengthened connections between scientific societies."My research is in the intersection of genetics, bioinformatics, developmental biology and evolutionary biology, so I belong to four different research societies," she says. "I hope this report will help knock down those barriers and stimulate more research that integrates multiple disciplines."The two goals focused on technology infrastructure are: Develop new technologies to revolutionize research; and Manage and realize the potential of Big Data.Co-author Eric Lyons, associate professor in the School of Plant Sciences at the University of Arizona, says such new technologies are necessary because plant research is a diverse set of sciences that span from molecules to the entire planet."Addressing the most pressing questions of plant research requires an unprecedented level of coordination, collaboration, and training across many disciplines of science," says Lyons. "This Decadal Vision is essential to bring a common voice to the needs of these diverse researchers and the central role that data science plays in facilitating integrating information to make new discoveries to improve the human condition through plants and agriculture."While the Decadal Vision makes a case for new funding, obtaining that support will require plant scientists to engage the public and advocate for needed resources.Indeed, federal funding agencies, private philanthropies, corporations and entrepreneurs, are all necessary for plant science to have a maximum impact on enhancing human health, improving environmental quality, boosting the economy, and benefitting global equity and justice."Plant science gets such a small piece of the funding pie. If there are going to be solutions to surviving climate change, then plants are going to be a critical part of those solutions," says Bartlett.Wendroth believes that funding agencies can foster plant science discoveries to address pressing global issues by calling for proposals in forward-thinking, interdisciplinary research with speculative outcomes. "This would help harness scientific creativity in a similar way that venture capital is used to invest in long-term growth potential opportunities," he says.
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Agriculture & Food
| 2,020 |
September 8, 2020
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https://www.sciencedaily.com/releases/2020/09/200908085429.htm
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International study gets at the root of what makes deer migrate
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From the Rocky Mountains to the Alps, the question of whether a deer population migrates can be answered by how springtime comes to the landscapes they occupy.
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That's the key finding of a first-of-its-kind study produced by a cross-continental team of researchers working with lead author Ellen Aikens, a recent doctoral student of the U.S. Geological Survey's Wyoming Cooperative Fish and Wildlife Research Unit at the University of Wyoming. The paper was published today (Sept. 7) in The researchers found that the dynamics of springtime plant growth, specifically whether green-up progresses like a wave or not, explains where migration occurs in many ecosystems. A slow and long spring green-up correlates to a resident strategy.In contrast, migratory behavior often is found in places where the green-up is shorter in any one place but progresses up in elevation. Migratory behavior emerges as a means for animals to track food in landscapes where pulses of the best forage actually move across the landscape as the spring season unfolds. This wave-like green-up is fleeting, and animals make the most of it by moving sequentially across large landscapes in a behavior that scientists call "green-wave surfing."The analysis combined vegetation data from satellites with GPS-tracking data from 1,696 individuals across 61 populations of four ungulate species: roe deer and red deer in Europe, and mule deer and elk in North America.Few other studies have combined movement and vegetation data at this large of a scale to get at the root of what makes deer migrate. This work was made possible through the collaboration of 36 biologists spread out across North America and Europe. The EuroDeer project contributed some of the most crucial datasets on roe deer and red deer movement.Intriguingly, researchers found that at the species level, migrants and residents received equal foraging benefits regardless of which movement strategy they employed. This finding suggests that the movement tactics of deer populations are fine-tuned to the dynamic way that forage resources move across the landscapes they inhabit.An important implication is that management and conservation of deer species are best tailored to local patterns of plant growth, and the particular behavioral adaptations that have arisen in each area.For example, roe deer don't have to move to secure the food they need due to the long springtime season in France or Belgium. However, in the Rocky Mountains or the Alps, to stay put is to be hungry and miss out on the best forage."This new research shows that ungulate movement is influenced by altered patterns of forage availability," Aikens says. "Migrations can be lost when changes in the underlying habitat eliminate the need to migrate over long distances."For example, shortened migrations or increased residency have been caused by food subsidies such as agriculture and supplemental feeding. In such altered landscapes, a switch to a resident strategy may be adaptive in a changing world.On the other hand, in less-developed areas where animals depend on migration to survive, climate-induced changes in the green wave -- or new barriers to movement such as highways or housing -- can reduce food availability. These changes might be early warning signals of future population declines."This research has global implications for the field of animal ecology and should help drive future conservation work," says Matthew Kauffman, director of the Wyoming Cooperative Fish and Wildlife Research Unit and a senior author of the study. "It allows us to understand more fully the types of landscapes where migration is required by ungulates and where conservation of corridors is thus paramount."
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Agriculture & Food
| 2,020 |
September 8, 2020
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https://www.sciencedaily.com/releases/2020/09/200908093740.htm
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Inheritance in plants can now be controlled specifically
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A new application of the CRISPR/Cas molecular scissors promises major progress in crop cultivation. At Karlsruhe Institute of Technology (KIT), researchers from the team of molecular biologist Holger Puchta have succeeded in modifying the sequence of genes on a chromosome using CRISPR/Cas. For the first time worldwide, they took a known chromosome modification in the thale cress model plant and demonstrated how inversions of the gene sequence can be undone and inheritance can thus be controlled specifically. The results are published in
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About 5,000 years ago, genetic information of thale cress was modified. To date, it has spread widely and is of major interest to science. On the chromosome 4 of the plant, a so-called inversion occurred: The chromosome broke at two points and was reassembled again. The broken out section was reinserted, but rotated by 180°. As a result, the sequence of genes on this chromosome section was inverted. This chromosome mutation known as "Knob hk4S" in research is an example of the fact that evolution cannot only modify the genetic material of organisms, but determine it for a long term. "In inverted sections, genes cannot be exchanged between homologous chromosomes during inheritance," molecular biologist Holger Puchta, KIT, explains.Inversions do not only affect thale cress (Arabidopsis thaliana), a wild plant used as a model organism in genetics due to its completely decoded genome and its small chromosome number. Inversions can also be found in crop plants. They are an obstacle to cultivation that uses modifications of the genetic material to produce maximum yields and a good taste of the plant and to make the plant resistant to diseases, pests, and extreme climatic conditions.For the first time, researchers from the Chair for Molecular Biology and Biochemistry held by Puchta at KIT's Botanical Institute have now succeeded in undoing natural inversions. "We considerably extended the applications of the CRISPR/Cas molecular scissors," Puchta says. "We no longer use the scissors for exchanging arms between chromosomes, but also for recombining genes on a single chromosome. For the first time, we have now demonstrated that it is possible to directly control inheritance processes. We can achieve genetic exchange in an area, in which this has been impossible before. With this, we have established chromosome engineering as a new type of crop cultivation."Together with researchers from the team of Professor Andreas Houben, Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) in Gatersleben, and Professor Paul Fransz from the University of Amsterdam, KIT scientists took the most prominent natural inversion hk4S on chromosome 4 of thale cress and demonstrated how this inversion can be undone and how genetic exchange can be achieved in cultivation. Their findings are reported in Nature Communications. The researchers also think that it is possible to use CRISPR/Cas to produce new inversions, which would be another step towards combining desired traits and eliminating undesired properties in crop cultivation.Holger Puchta is considered a pioneer of genome editing with molecular scissors using the natural principle of mutation to precisely modify the genetic information in plants without introducing foreign DNA. His current project "Multidimensional CRISPR/Cas mediated engineering of plant breeding," CRISBREED for short, now focuses on the recombination of plant chromosomes by means of CRISPR/Cas technology. CRISPR (stands for Clustered Regularly Interspaced Short Palindromic Repeats) represents a certain section on the DNA that carries the genetic information. Cas is an enzyme that recognizes this section and cuts the DNA precisely at that point in order to remove, insert, or exchange genes, recombine chromosomes, and for the first time modify the gene sequence on them.
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Agriculture & Food
| 2,020 |
September 8, 2020
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https://www.sciencedaily.com/releases/2020/09/200908085457.htm
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Gen Z not ready to eat lab-grown meat
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Gen Z are the new kids on the block. As a cohort of 5 million people born between 1995-2015 encompassing 20 percent of the Australian population and 2 billion people globally -- they're consumers to be reckoned with.
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New research by the University of Sydney and Curtin University to published on 8 September in However, despite their lack of enthusiasm for the new meat alternative, 41 percent believed it could be a viable nutritional source because of the need to transition to more sustainable food options and improve animal welfare."Our research has found that Generation Z -- those aged between 18 and 25 -- are concerned about the environment and animal welfare, yet most are not ready to accept cultured meat and view it with disgust," said the study's lead researcher, Dr Diana Bogueva from the University of Sydney's School of Chemical and Biomolecular Engineering.59 percent of participants were concerned about the environmental impact of traditional livestock farming specifically, however many were not clear on what those impacts were nor did they understand the associated resource depletion."In-vitro meat and other alternatives are important as they can help to reduce greenhouse emissions and lead to better animal welfare conditions. However, if cultured meat is to replace livestock-based proteins, it will have to emotionally and intellectually appeal to the Gen Z consumers. It may be through its physical appearance, but what seems to be more important is transparency around its environmental and other benefits," said Dr Bogueva.The participants had several concerns relating to cultured meat, including an anticipated taste or disgust, health and safety, and whether it is a more sustainable option.Societal concerns were also prevalent throughout the study, with a large number of respondents worried that eating cultured meat would be in conflict with perceptions of gender and national identity."Gen Z value Australia's reputation as a supplier of quality livestock and meat, and many view traditional meat eating as being closely tied to concepts of masculinity and Australian cultural identity," said Dr Bogueva.Others were concerned about animal welfare, whereas some viewed cultured meat as a conspiracy orchestrated by the rich and powerful and were determined not to be convinced to consume it. Several participants were also unsure whether cultured meat was an environmentally sustainable option."Generation Z are also unsure whether cultured meat is actually more environmentally sustainable, described by several respondents as potentially "resource consuming" and not being "environmentally friendly"," said Dr Bogueva."The respondents were effectively divided into two groups: the "against" described cultured meat as "another thing our generation has to worry about" and questioned the motivations of those developing it, while supporters described it as "money invested for a good cause" and "a smart move" by people who are "advanced thinkers.""This Generation has vast information at its fingertips but is still concerned that they will be left with the legacy of exploitative capitalism that benefits only a few at the expense of many. They have witnessed such behaviour resulting in climate change and are now afraid that a similar scenario may develop in relation to food, particularly as investors are pursuing broader adoption of cultured meat," Dr Bogueva said.17 percent of respondents rejected all alternatives, including cultured meat, seeing it as chemically produced and heavily processed.11 percent rejected all alternatives in favour of increased consumption of fruit and vegetables, saying they will stick with a vegetarian diet.35 percent rejected cultured meat and edible insects but accepted plant-based alternatives because they "sounded more natural" and are "normal."28 percent believed cultured meat was acceptable or possibly acceptable if the technology could be mastered.A fifth group (9 percent) accepted edible insects but rejected cultured meat as it was too artificial and not natural like insectsThe researchers collected Generation Z's opinions of cultured meat via an online survey. 227 randomly selected, Australian-based respondents were asked questions about their demographics, dietary preferences (such as how often they liked to eat meat), how they felt about cultured meat and whether they thought it was necessary to accept and consume, as well as their preference for different meat alternatives (such as insects, plant based and cultured meat).
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Agriculture & Food
| 2,020 |
September 7, 2020
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https://www.sciencedaily.com/releases/2020/09/200907112331.htm
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Producing leather-like materials from fungi
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An international team led by material chemists Alexander Bismarck and Mitchell Jones from the University of Vienna demonstrate the considerable potential of these renewable sustainable fabrics derived from fungi in their latest review article in
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Traditional leather and its alternatives are typically obtained from animals and synthetic polymers. Leather can be considered a co-product of meat production with both livestock farming and the leather production process increasingly considered to be ethically questionable and environmentally unfriendly (e.g. deforestation for grazing, greenhouse gas emissions, use of hazardous substances in the tanning process). The production of synthetic leather materials from plastics such as polyvinyl chloride (PVC) or polyurethane (PU) also depend on chemicals derived from fossil fuels."This is where leather-like materials from fungi come into play, which, in general, are COLeather substitutes can be produced from fungi by upcycling low-cost agricultural and forestry by-products (e.g. sawdust). These serve as a feedstock for the growth of fungal mycelium, which constitutes a mass of elongated tubular structures and represents the vegetative growth of filamentous fungi. Within a couple of weeks, the fungal biomass can be harvested and physically and chemically treated (e.g. pressing, cross-linking). "As a result, these sheets of fungal biomass look like leather and exhibit comparable material and tactile properties," says department head Alexander Bismarck. The first biotech companies are already marketing materials derived from fungi.Leather substitute materials derived from fungi typically contain completely biodegradable chitin (which acts as a stabiliser in the material) and other polysaccharides such as glucans. In their own studies, Alexander Bismarck and Mitchell Jones (now affiliated with Vienna University of Technology) already conducted research using fungal species, such as the white button mushroom A. bisporus and bracket fungus D. confragosa, to produce paper and foam-like construction materials for applications, such as insulation.In this review article, the scientists examine the sustainability of bovine and synthetic leathers and present an overview of the first developments and commercialisation of leather substitutes derived from fungi. According to the authors, one of the greatest challenges in the production of fungi-derived leather-like materials is still to achieve homogeneous and consistent mycelium mats, "exhibiting uniform growth and consistent thickness, colour and mechanical properties."To date, the production of these materials has been driven mainly by entrepreneurial spirit. Fungi as a raw material for leather substitutes provide a cost-effective, socially and environmentally sound alternative to bovine and synthetic leather and are of particular interest to sustainability-conscious consumers and companies as well as to the vegan community, the researchers write. According to them, "substantial advances in this technology and the growing number of companies that are producing fungi-biomass-based leather alternatives suggests that this new material will play a considerable role in the future of ethically and environmentally responsible fabrics."
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Agriculture & Food
| 2,020 |
September 2, 2020
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https://www.sciencedaily.com/releases/2020/09/200902182423.htm
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Food-web threats from common insecticides
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In light of emerging evidence showing how a commonly used class of insecticides can spread through the environment to pollinators, predators and other insects they are not intended to kill, researchers are warning about the potential for widespread environmental contamination.
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In an opinion in the journal "Since the research has focused on transmission of the insecticide from a plant to a particular pest to a predator of the pest, it's ignored the hundreds of other herbivores that are also on that plant, and also transmission of that material to their predators. That's where the food web concerns come in that we're interested in," said Steven Frank, co-author of the opinion and a professor in NC State's Department of Entomology and Plant Pathology.Since their introduction in the early 1990s, neonicotinoids have become the most widely used insecticides in the world, researchers said. In 2014, these products represented 25 percent of the global pesticide market, other scientists have reported. The authors also said they are among the most toxic insecticides to insects ever developed.These insecticides are used in crops, lawns and landscapes, livestock production and even in pet flea and tick products. They are also used in lawns, commercial landscapes and to protect trees. For example, neonicotinoids were used to treat 200,000 hemlock trees in Great Smoky Mountains National Park."They are applied to hundreds of thousands of trees each year for protection from exotic pests, which can be lethal to trees, but also from cosmetic pests, which generally are not lethal," Frank said.Recently, a study uncovered a new way that neonicotinoids can spread through the food chain.Published last year in the "We've known that neonicotinoids can be transmitted through nectar and pollen and can harm pollinators that way -- directly from the plants," Frank said. "We've known that if herbivores feed on the plants and predators eat those herbivores, that they could be harmed because the neonicotinoids accumulate in the herbivores' bodies. This was a new revelation that it could be transmitted through the herbivore to the environment as a carbohydrate that a lot of animals feed on."The authors said this raises the potential for additional off-target effects to other organisms as the toxin is spread by organisms that are not killed as they ingest it."This adds one more example of how the material can move in a three-part food chain from the plant to an herbivore to a predator," Frank said. "That's been documented now a couple of times. Our concern is that if it can do that, it seems evident that it could spread much wider throughout the entire food web because insect populations are so diverse and abundant on plants."Frank said their concern goes beyond insects. If ingested by organisms that are not killed directly, those organisms could pass the toxin on to insects, birds, amphibians or others."Insects are food for thousands of different vertebrates -- everything from birds to mice, lizards and frogs, and fish," Frank said. "All of those things eat insects. As the environment fills with contaminated insects, other organisms could be eating them. Even though the neonicotinoids have relatively low mammalian toxicity, which makes them safer for applicators, there is still risk of some toxicity, and there could be toxicity for other vertebrates."The authors said one potential way to curb their use is to refrain from using them preventively as seed coatings in crop fields, where they have been shown to have limited benefit. One study found they benefit just 5 percent of crop fields when applied preventively to seeds."We're putting these materials into the environment even though, in some cases, there's no tangible benefit to them," Frank said. "It seems like their use could be reined in substantially without hurting farmers or the economy."More research is needed, Frank said, to understand the full effect on food webs and the environment."The concern is for biodiversity generally, where we don't know how far through the food web these materials travel, and to what consequence," Frank said. "We're seeing biodiversity of insects and other things decline around the world. There are a multitude of factors contributing to this that we don't know the extent of, but this could be playing a role. And the other concern is general environmental contamination."
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Agriculture & Food
| 2,020 |
September 2, 2020
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https://www.sciencedaily.com/releases/2020/09/200902114349.htm
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New study on migration success reinforces need for monarch butterfly milkweed habitat
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A recently published analysis of data on tagged monarch butterflies migrating from the United States to Mexico emphasizes the importance of creating new habitat to ensure the future of the species' iconic migratory pattern.
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The study, published this month in the peer-reviewed journal Several lines of evidence support the primary hypothesis for the monarch population decline, which is the loss of milkweed habitat. John Pleasants, an adjunct associate professor in Iowa State University's Department of Ecology, Evolution and Organismal Biology, said the analysis should put to rest this persistent alternative explanation for the population decline that posits monarch butterflies are experiencing increasing mortality during their fall migration to Mexico, Pleasants said."If there was some problem with migration, we should have found fewer tagged monarchs recovered in Mexico over time, but that was not the case," he said.Monarch butterflies carry out a remarkable migration pattern year after year. Monarchs born in Midwestern states move south during the late summer and fall and arrive in central Mexico for the winter. The monarchs then move northward again in the spring. But the monarch population has dwindled to such an extent over the last two decades that scientists worried the migratory system could collapse forever.In response, the Iowa Monarch Conservation Consortium, a diverse partnership of 45 organizations supported by Iowa State University, the Iowa Department of Agriculture and Land Stewardship, and the Iowa Department of Natural Resources, is spearheading an effort to plant between 480,000 and 830,000 acres of new habitat by 2038. This effort focuses on milkweed, the only plant on which monarchs will lay eggs.Pleasants said some researchers looked at yearly surveys of monarch adults and did not find a decline at the same time the overwintering population in Mexico was falling and hypothesized that increasing mortality during the southward migration may be driving the overall population decline. Those researchers suggested increased parasite load or declining nectar availability in Texas might contribute to migratory mortality. However, Pleasants said no reliable data show a decline in those factors. Instead, Pleasants said the data show no trend in the tag recovery rate, an indication the migratory journey hasn't become more dangerous over the years.Pleasants said the discrepancy between the surveys of the summer populations and the overwintering population likely stems from the loss of milkweed habitat on agricultural land in the Midwest. Milkweed was once plentiful in farm fields, providing plenty of habitat for monarchs in rural areas, until about 2006 when it had all but disappeared due to herbicide use. Surveys done in the late 1990s and early 2000s did not include field habitat and therefore missed the monarchs in fields, underestimating the true size of the population, Pleasants said. Since 2006, population estimates from those surveys have been highly correlated with overwintering numbers."Our analysis points us back to the idea that the loss of milkweeds, particularly from agricultural fields, is most responsible for this decline," he said. "If you want to bring the monarch butterfly back, you need to bring the milkweeds back."
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Agriculture & Food
| 2,020 |
September 2, 2020
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https://www.sciencedaily.com/releases/2020/09/200902101816.htm
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Regional variations in freshwater overconsumption
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Freshwater -- which falls to the earth as precipitation or exists beneath the surface as groundwater -- is desperately needed to sustain people, plants and animals. With an ever-increasing human population, water shortages are already occurring in many areas are only expected to get worse. Now, researchers reporting in ACS'
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People use freshwater for many essential purposes, including drinking, hygiene and irrigating crops. Studies have estimated that the current global level of freshwater consumption does not exceed the global supply. However, regional variations exist, and the need to grow more food for larger populations will increase freshwater demand. In addition, international trade -- for example, water-scare countries importing food from water-rich countries -- can influence regional freshwater supply and demand. Masaharu Motoshita and colleagues wanted to conduct a comprehensive analysis of how much freshwater is available for human consumption in many different regions. They also wanted to determine how much of this water is essential to sustain human life, and how much is surplus or "luxury" consumption.To find out, the researchers calculated the freshwater available for humans in about 11,000 watersheds around the world and compared that amount with the water consumed in that region for basic human needs (drinking water, food production and hygiene), as well as luxury use. They found that about 24% of total freshwater used by humans in these watersheds exceeded regional capacities, often at the expense of ecosystems. About 59% of this overconsumption was to satisfy basic human needs, while the rest was luxury use. In many areas, overconsumption occurred only at certain times of the year. International trade alleviated about 4.8% of global overconsumption. Although options to reduce water overconsumption vary by region, some possibilities include improving irrigation efficiency, shifting to less water-intensive crops or different production sites, increasing water storage in reservoirs, reducing food waste and changing food consumption patterns, the researchers say.
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Agriculture & Food
| 2,020 |
August 31, 2020
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https://www.sciencedaily.com/releases/2020/08/200831112349.htm
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Prior exposure to powdery mildew makes plants more vulnerable to subsequent disease
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Next time you head outside for a socially distant walk in between your Zoom meetings, notice the rich diversity of plants along your path. As we approach late summer, be sure to also notice the diversity of disease symptoms on those plants, including spots, blotches or fuzzy growth caused by bacteria, viruses or fungi.
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A key to surviving in the wild is fighting off infection -- and not just once. As in humans, one infection may or may not leave a plant with lasting immunity.In fact, an early infection might make things worse. New research from an international team including an assistant professor of biology at Washington University in St. Louis shows that infection actually makes a plant more susceptible to secondary infection -- in experiments and in the wild. The findings are published in the Aug. 31 issue of "We found that early infection facilitated later infection," said Rachel Penczykowski, assistant professor of biology in Arts & Sciences and co-first author on the study. She performed the field experiments as a postdoctoral researcher with Anna-Liisa Laine, senior author on the paper, now at the University of Zürich."And the order in which pathogen strains infect a plant matters," Penczykowski said. "Some pathogen strains are especially likely to facilitate infection by later-arriving strains."The findings -- obtained through a series of elegant experiments that capture how pathogen strains naturally accumulate on plants over a growing season -- reveal the importance of understanding interactions among pathogens when developing strategies for maintaining healthy crop populations.A common roadside weed, In the wild, plant populations are exposed to and infected by multiple powdery mildew strains over the course of their lifetime. The authors wondered if prior exposure to one strain of powdery mildew affects the plant's susceptibility to a second.To simulate what would happen in the wild, the authors took young, disease-free plants and brushed pathogen spores from one of four pathogen strains onto a single leaf per plant. The rest of the leaves were temporarily covered with a plastic bag.The inoculated leaf was then covered with a spore-proof pouch for the duration of the experiment, which prevented infection from spreading between it and the other leaves. This method works because powdery mildew produces a localized, leaf-surface infection that does not spread systemically in the plant. Otherwise identical control plants received a sham inoculation instead of powdery mildew spores.The plants were then placed in a common garden environment in a large field (without locally occurring Plantago or powdery mildew), where they were simultaneously exposed to all four pathogen strains.Penczykowski and co-first author Fletcher Halliday, a current postdoctoral researcher in the Laine lab, found that none of the four strains of powdery mildew inoculated onto plants protected the plants from a secondary infection. In fact, prior exposure to mildew made plants more susceptible to a second powdery mildew infection compared to infection-naïve controls."If you look at each strain individually, some of the strains were better than others at promoting later infection," Penczykowski said."Because crop plants may also be exposed to a diversity of pathogen strains during a given growing season, understanding the ways in which different pathogen strains impact each other is important for developing sustainable disease control strategies in agricultural systems."Scientists sometimes place cohorts of healthy, greenhouse-grown "sentinel plants" into field populations to measure the risk of pathogen infection. Doing this with sentinel plants allows researchers to control for genetic background, age and condition.To test how prior inoculation affected the probability of plants becoming infected during epidemics in wild populations, the authors inoculated plants as they did in the common garden experiment (again, with uninoculated controls for comparison). Except this time, they moved the potted sentinel plants into wild populations and waited for naturally occurring mildew spores to arrive.The researchers found that previously infected sentinel plants acquired secondary mildew infections more often than control plants that had never been infected. This was true even though the only way plants were catching the naturally occurring pathogen strains was through the wind."What we saw in both our common garden and our sentinel plant experiments was that previously inoculated plants were more susceptible to later infection," Halliday said. "But could we detect the signature of pathogen strain facilitation in naturally infected wild plant populations? That would require an intensive survey of wild plant-pathogen dynamics."And into the wild the scientists went -- that is, using data from wild populations that were fortunately collected the previous year.In an intensive survey of 13 field populations, the scientists tracked mildew infection in wild plants over the course of two months. They tagged plants as they found mildew infection; otherwise, they were not manipulated in any way and had been growing in the field their whole lives.A small leaf area of each infected plant was cut and brought to the lab to identify the mildew strains that infected the plants at different times throughout the growing season.Powdery mildew strains vary in their ability to survive the winter and in the timing of their reproductive cycle.Some strains arrive earlier in the growing season and are likely to be the ones that had successfully overwintered and reproduced quickly.Halliday dove into the genetic data compiled from the surveys of the 13 field populations and found that strains detected early in the season commonly facilitated subsequent infections, and strains that arrived to the populations later in the season benefited from that facilitation."The early-arriving strains are the ones that are driving the course of epidemics and also affecting the diversity of pathogen strains that assemble in plant populations," Halliday said."In other words, the strains that are ready to hit the ground running in spring may impact both the ecological and evolutionary dynamics of plant-pathogen interactions," Penczykowski added.
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Agriculture & Food
| 2,020 |
August 31, 2020
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https://www.sciencedaily.com/releases/2020/08/200831112318.htm
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Insect shows promise as a good, sustainable food source
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With global food demands rising at an alarming rate, a study led by IUPUI scientists has found new evidence that a previously overlooked insect shows promise as alternative protein source: the yellow mealworm.
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The research is based upon a new analysis of the genome of the mealworm species Tenebrio molitor led by Christine Picard, associate professor of biology and director in Forensic and Investigative Sciences program at the School of Science at IUPUI.The work was published in the "Human populations are continuing to increase and the stress on protein production is increasing at an unsustainable rate, not even considering climate change," said Picard, whose lab focuses on the use of insects to address global food demand.The research, conducted in partnership with Beta Hatch Inc., has found the yellow mealworm -- historically a pest -- can provide benefit in a wide range of agriculture applications. Not only can it can be used as an alternative source of protein for animals including fish, but its waste is also ideal as organic fertilizer.Picard and her team sequenced the yellow mealworm's genome using 10X Chromium linked-read technology. The results will help those who now wish to utilize the DNA and optimize the yellow mealworm for mass production and consumption. This new technology integrates the best of two sequencing methods to produce a reliable genome sequence."Insect genomes are challenging, and the longer sequence of DNA you can generate, the better genome you can assemble," said Picard.Picard added the mealworm has -- and will have -- a wide variety uses."Mealworms, being insects, are a part of the natural diet of many organisms," said Picard. "Fish enjoy mealworms, for example. They could also be really useful in the pet food industry as an alternative protein source, chickens like insects -- and maybe one day humans, too, because it's an alternative source of protein."Next, Picard said the researchers plan to look at what governs some of the biological processes of yellow mealworms in order to harness information useful for the commercialization of these insects.
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Agriculture & Food
| 2,020 |
August 31, 2020
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https://www.sciencedaily.com/releases/2020/08/200831094727.htm
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How weather affects crawfish harvests
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The life cycle of a crawfish can be fairly straight forward. In the summer months, crawfish reproduce in underground mud burrows with a plug of mud on top of the burrow to protect them from predators. In late summer and early fall, rain softens the mud plugs so the crawfish can push their way out of the burrows and enter ponds, where they feed, molt and grow throughout Louisiana's typically mild winters. Spring then brings crawfish harvest season.
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However, temperature and seasonal weather changes can affect this life cycle. Variability can have a costly effect on the industry, which has experienced considerable growth over the past two decades. For example, the 2018-19 Louisiana crawfish season produced 151.8 million pounds of crawfish with an economic value of $209.5 million compared to 82 million pounds valued at about $45 million in the 2004-05 season, according to the LSU AgCenter. To help inform farmers, researchers at LSU are the first to quantify how rainfall and temperature affect crawfish harvest yields."Providing farmers and producers with more information on how their catch and livelihood may fluctuate due to environmental conditions can help make them more resilient in the future," said LSU Assistant Professor-Research and the Southern Climate Impacts Planning Program Climate Research Director Vincent Brown, who is the lead author on this study published in Brown and his colleagues analyzed eight years of crawfish harvest data from six LSU Aquaculture Research Station ponds. They used a statistical model to identify the most significant temperature and weather variables that impact crawfish."The timing of precipitation is really important. The statistical model shows that if you have heavy rainfall in August or September, the crawfish harvest yields will be suppressed in the spring," Brown said.Heavy summer rains can trigger the crawfish to emerge from their burrows too early. When this happens, they enter ponds that could potentially have low oxygen due to decaying plant matter and high summer heat as well as a host of other things that could be harmful to their survival."We have seen how the low amount of dissolved oxygen in a pond can directly affect the survival rate of crawfish. This issue is something that we are continuing to study and develop best practices with the farmers to combat," said C. Gregory Lutz, LSU AgCenter Aquaculture Research Station professor, Louisiana Sea Grant College Program marine extension agent and study co-author.Additionally, winter temperatures that drop below freezing can slow crawfish growth.This information can benefit farmers. For example, if excessive precipitation occurs in August and September followed by a dry October and November plus freezing conditions in January, farmers may not need to set aside time and resources to harvest two to four days per week in February, which is generally prescribed. It is possible that only harvesting twice a week is sufficient, which can save farmers money on bait, labor, gas and other costs, write the researchers."This study can also serve as a template to investigate the impacts of weather on other farm-raised seafood products," said Mark Shirley, Louisiana Sea Grant College Program and LSU AgCenter marine extension agent and co-author of this study.
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Agriculture & Food
| 2,020 |
August 28, 2020
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https://www.sciencedaily.com/releases/2020/08/200828140301.htm
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Vietnam farmers' poultry sales during outbreaks may increase virus transmission
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Small-scale poultry farmers in Vietnam tend to respond to viral outbreaks of highly pathogenic avian influenza (HPAI) by rapidly selling their birds as a way to avoid financial loss, according to a new study by an international team of researchers. As these birds are commingled with other birds in markets and trading networks, this practice may increase the likelihood of widespread disease transmission. The findings could have implications for government policymaking in the many regions of the world where small-scale poultry farming and avian influenza risk co-occur.
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"Avian influenza is deadly to humans, with a case fatality rate between 25% and 50%," said Maciej Boni, associate professor of biology, Penn State. Fortunately, reports of human-to-human transmission over the past 15 years have been either absent or anecdotal. COVID-19 took us by surprise, but with HPAI we have a known threat with the potential to become pandemic. If we ignore the active role that poultry farmers play in the control and dissemination of avian influenza, we may miss another opportunity to curtail an emerging disease outbreak at a stage when it is still controllable."Lead author Alexis Delabouglise, an animal health economist at CIRAD-Agricultural Research for Development in France who was a postdoctoral scholar at Penn State when the research was performed, explained that small-scale poultry farming is practiced by millions of Vietnamese households and by millions more throughout southeast Asia, mostly on a scale of fewer than 100 birds per farm. These farmers make decisions on a daily basis -- often in response to economic incentives -- about when and where to sell their flocks. And their decisions can influence disease spread."If the price of poultry goes up, farmers might expand their farming activities, which could create more outbreak risk," said Delabouglise. "If there is an outbreak on a neighboring farm, they might choose to sell their poultry early to avoid their own birds from being infected and to avoid lower prices. And if there is an outbreak on their own farm, the evidence in our study shows that they would be likely to sell their birds early to avoid both monetary loss and epidemiological risk."Boni and colleagues, including researchers at the Oxford University Clinical Research Unit (OUCRU) in Ho Chi Minh City, conducted a longitudinal study of small-scale poultry farms in the Mekong river delta region of southern Vietnam with a goal of characterizing the effects of disease outbreaks on poultry harvest rates, as well as on two prevention practices -- vaccination and farm disinfection. The team followed 53 farmers and their management of more than 1,000 poultry flocks for a period of two years -- from 2015 to 2017."Working with partners in endemic countries day-in and day-out on study details and public health priorities is key to establishing collaborations that allow these long-term follow-up studies to succeed," said Boni, who led a research group at OUCRU for eight years.Delabouglise, the statistical lead on the project, used mixed-effects general additive models to investigate farmers' probabilities of harvesting -- either selling or slaughtering -- flocks, of performing avian influenza vaccination on flocks that were not previously vaccinated and of disinfecting farm facilities when faced with an outbreak. Their findings appeared in "We found that farmers did send their chickens to market early when there were outbreaks occurring on their farms," said Delabouglise. "Specifically, small-scale farmers increased their harvest of broiler chickens by 56% during outbreaks with no sudden deaths and by 214% during outbreaks with sudden deaths. This has the potential to exacerbate the outbreak and spread the virus even further."The team noted that sudden deaths -- the deaths of chickens less than one day after the onset of clinical symptoms -- are considered to be indicative of HPAI infection. Interestingly, the team found that the probability of disinfection was not affected by the occurrence of outbreaks.Finally, the team found that the likelihood of vaccination against avian influenza strongly increased with flock size. The probability of vaccination was almost zero for flocks of 16 birds or fewer and nearly 100% for flocks of more than 200 birds. According to Delabouglise, one reason that millions of small-scale poultry farmers may not be vaccinating their birds could be their desire to avoid transaction costs associated with declaring flocks to governmental veterinary services before vaccination. Another reason could be that due to their small size, their vaccination status is not controlled and, therefore, vaccination is less worthwhile from the farmers' perspective."Crucially, it is these smaller flocks that are more likely to be sold into trading networks during outbreaks," he said. "The rapid sale of sick birds can contaminate other birds at traders' storage places and those at live bird markets. It also exposes consumers and traders, slaughterers and retailers to an increased risk of infection."Delabouglise noted that, on the flip side, a massive arrival of underage birds in a live bird market, or a price decrease due to the temporary oversupply of poultry, may be a sign that an outbreak is occurring."This is an interesting area for surveillance of livestock diseases," he said.Delabouglise said that the team's results could help governmental agencies create policies that aim to avoid the spread of HPAI."Small-scale farmers could play an active role in the control of emerging infectious diseases if they are given the opportunity to depopulate their farm upon disease detection without disseminating pathogens in trade circuits," he said. "Policymakers could encourage the establishment of formal trade agreements that encourage such 'virtuous' management of disease outbreaks in poultry."One such "virtuous" management strategy could be for farmers to sell their sick chickens as feed for pythons and crocodiles raised on neighboring farms. Another could be to set up agreements with neighboring large commercial farmers who can give them financial indemnities to destroy the birds as a way of protecting their own flocks."It would be impossible to have reliable public-health control over the millions of small-scale poultry flocks in a place like Vietnam," said Delabouglise, "but providing economic incentives to responsibly manage birds during disease outbreaks is feasible."Other authors on the paper include Nguyen Thi Le Thanh, Wellcome Trust Major Overseas Programme; Huynh Thi Ai Xuyen, Ca Mau Sub-Department of Livestock Production and Animal Health; Benjamin Nguyen-VanYen, Wellcome Trust Major Overseas Programme and Ecole Normale Superieure; Phung Ngoc Tuyet, Ca Mau Sub-Department of Livestock Production and Animal Health; and Ha Minh Lam, Wellcome Trust Major Overseas Programme and University of Oxford.The Defense Threats Reduction Agency, the Wellcome Trust and the Pennsylvania State University supported this research.
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Agriculture & Food
| 2,020 |
August 27, 2020
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https://www.sciencedaily.com/releases/2020/08/200827155003.htm
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Genetics of the tree of life
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The African baobab tree (
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The African baobab tree has 168 chromosomes -- critical knowledge for further genetic studies, conservation, and improvement for agricultural purposes. The findings were published in the journal "We were able to unequivocally count the chromosomes," says Nurul Faridi, a USDA Forest Service research geneticist who co-led the study with Hamidou Sakhanokho, a USDA Agricultural Research Service research geneticist.The researchers used fluorescent probes to see the genetic components of individual chromosomes within the cells -- which glow like jewels.The analysis also revealed that the tree has a massive nucleolus organizer region (NOR). Relative to the main chromosome body, this region appears larger than that of any other plant species. During certain stages of the cell cycle, nucleoli form at the NORs. The nucleoli are essential for ribosome assembly and protein synthesis in eukaryotes and are an important feature that differentiates eukaryotes from prokaryotes."These genetic findings are foundational and will make genetic conservation of the African baobab tree more efficient and effective," says Dana Nelson, a coauthor and project leader of the Southern Research Station's genetic unit. "This research is also a precursor for tree breeding programs seeking to improve baobab for silvicultural applications."
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Agriculture & Food
| 2,020 |
August 27, 2020
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https://www.sciencedaily.com/releases/2020/08/200827105926.htm
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Genomes published for major agricultural weeds
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Representing some of the most troublesome agricultural weeds, waterhemp, smooth pigweed, and Palmer amaranth impact crop production systems across the U.S. and elsewhere with ripple effects felt by economies worldwide. In a landmark study, scientists have published the most comprehensive genome information to date for all three species, marking a new era of scientific discovery toward potential solutions.
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"These genome assemblies will greatly foster further research on these difficult weed species, including better understanding the ways in which they evade damage from herbicides," says Pat Tranel, professor and associate head of the Department of Crop Sciences at the University of Illinois and co-author on the Draft genomes had already been published for waterhemp and Palmer amaranth, but techniques used in the All three genomes were assembled using advanced long-read sequencing, which maintains the integrity and continuity of the genome similar to the way large puzzle pieces provide a clearer picture of the whole than small pieces. In Palmer amaranth, an additional sequencing technology (chromatin conformation capture sequencing) was used to further order pieces of the genome that were assembled using the long-read information."The goal of any genome assembly is to reveal the complete arrangement of genes in the genome, broken into chromosome-sized fragments. Unfortunately, until recently, quality genome assemblies have been very labor intensive and expensive. The previously published draft genomes for these species reported the genome broken into thousands of pieces, while the assemblies we report are down to hundreds. The vast majority of the sequence is now assembled into very large fragments," says Jacob Montgomery, a graduate student working with Tranel and first author on the study.To further improve the assembly of the genomes for waterhemp and smooth pigweed, the team used an innovative approach known as trio binning, developed in cattle. Not only had this technique never before been fully utilized in plants, it had also not been used with parents from different species.In normal reproduction, male and female parents each contribute one copy of every gene to their offspring. In this case, offspring are diploid, meaning they have two copies of every gene. In the study, the team created hybrid offspring from two separate species: waterhemp and smooth pigweed. These offspring are still diploid, but the trio binning technique allowed the researchers to pull apart and isolate the two copies from each parent species, resulting in haploid (single copy) genomes for each."This approach resolved a problem in the previous waterhemp genome assembly. When parent alleles (copies of each gene) are very different from each other, as is often the case in outcrossing species such as waterhemp, the genome assembly program interprets them to be different genes," Tranel says. "With only one allele from each species, we were able to obtain a much cleaner assembly of their gene sequences."Detlef Weigel, director of the Max Planck Institute for Developmental Biology and co-author on the study, adds, "I am a big fan of the new advanced sequencing techniques, but even though they should theoretically be sufficient to sort out the arrangement of genes, in practice they are not. This is where genetics can help out, using information on whether genes were inherited from mom or dad. This allowed us to assign each gene to either a maternal or paternal chromosome."The researchers specifically chose waterhemp as the male parent in the smooth pigweed × waterhemp cross because the previously published waterhemp genome was from a female plant. Tranel is pursuing research to understand the genetic basis for maleness and femaleness in waterhemp and Palmer amaranth, with potential applications toward introducing female sterility as a future control method."The genomes of the male waterhemp and Palmer amaranth already have enabled my group to make rapid progress on identifying the potential genes that could be responsible for the determination of sex (male or female) in both species," Tranel says.Importantly, the genomes for all three species could start to chip away at the problem of herbicide resistance in these weeds. More and more, scientists are uncovering evidence of non-target-site or metabolic resistance in waterhemp and Palmer amaranth, allowing the weeds to detoxify herbicides before they can cause damage. Unfortunately, it is usually very difficult to determine which specific enzyme, among hundreds, is responsible for detoxifying the herbicide.Now, researchers will essentially be able to sort through a list to find the culprit with the hope of either knocking out the enzyme responsible or modifying the herbicide molecule to evade detoxification."Innovation is essential for the future of agriculture. We at BASF are working continuously on improving our products and services including sustainable solutions for the management of herbicide-resistant weeds. We want to better understand the amaranth biochemical resistance mechanisms in order to offer farmers new products and solutions for optimal control of key weeds," says Jens Lerchl, head of early biology research on herbicides at BASF and study co-author. Lerchl coordinated the Palmer amaranth genome work with KeyGene/Wageningen -The Netherlands."The area of genome sequencing is highly dynamic. That is why BASF chose KeyGene as the partner for both latest sequencing technology and bioinformatics. Together with the expertise of the University of Illinois and Max Planck Society, we were able to compare genomes and address specific biological topics," Lerchl says. In addition to collaborating on this research, BASF is also a founding member of the International Weed Genomics Consortium, led by Colorado State University aiming at the sequencing and analysis of ten high priority key weeds.
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Agriculture & Food
| 2,020 |
August 27, 2020
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https://www.sciencedaily.com/releases/2020/08/200827102148.htm
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Genetic link between cattle temperament and autism in humans
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A strong association between the genes influencing cattle temperament and autism in humans has been discovered by University of Queensland researchers.
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UQ genomic expert Professor Ben Hayes said the research by his interdisciplinary team headed by Dr Roy Costilla could lead to improved animal welfare and meat quality."The research doesn't mean that cattle have autism; rather that cattle share an overlap of genes with humans which are critical in brain function and response to fear stimuli," Professor Hayes said.Temperament is an important trait for day-to-day management of cattle."We knew that genetic factors were likely influence temperament in cattle and we thought that genes involved in behavioural traits in humans could also influence temperament in cattle."We found that genes known to contribute to autism spectrum disorders also influence temperament in cattle."Professor Hayes said the results were important as it opened the way for research conducted on behavioural traits in humans to shed further light on temperament in cattle."As I've found talking to farmers over the years, it can be distressing having an animal that has a poor temperament in the mob, and stirs up all the other cattle putting them into a state of stress."If we can identify those animals early, or breed to eliminate them, we can potentially reduce the stress of the whole mob."That has great implications for welfare -- not only of the cattle but also the people handling the cattle who are less likely to be charged or kicked."Professor Hayes said there was an association between a calmer temperament in cattle and better meat quality."The cattle industry's standard for measuring temperament is 'flight time' -- the speed in which cattle move after release from an enclosure," Professor Hayes said."What a producer wants is cattle that move calmly and slowly from the enclosure, rather than an animal that charges out in an aggressive or stressed state."Our study found flight time is about 35 percent heritable, which is very significant."It means you can make a lot of progress by breeding for better temperament -- it's about the same as milk production in dairy cattle, and we've made big breeding gains there."Professor Hayes said the same genes were identified in other genomic research conducted on domestication of foxes."The same genes just come up again and again," he said. "Some DNA variants in those genes are more common in people with autism and, in cattle, some DNA variants in those same genes are found to make the cattle more fearful in new situations and have a reactive temperament."It's the first time whole genome sequencing has been used to analyse temperament in beef cattle. Researchers looked at 28 million data points per animal on the 9,000 cattle with temperament records in the initial study, and then validated the results in over 80,000 cattle from Ireland.Professor Hayes said his team would incorporate the temperament data into a panel of markers available for producers that would also provide breeding values for fertility."It means a producer will be able to use a sample of tail hair which contains DNA to quickly get information on the genetic value of their animals for temperament and fertility. The temperament analysis was conducted primarily in northern cattle The study was a result of strong cooperation between Australian researchers, the beef industry and international collaborators from Ireland and Brazil.
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Agriculture & Food
| 2,020 |
August 27, 2020
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https://www.sciencedaily.com/releases/2020/08/200827101841.htm
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Are all vegetarian diets healthy?
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Vegetarian foods are not equally healthy, according to research presented today at ESC Congress 2020.
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"Our study highlights the variable nutritional quality of plant foods," said author Dr. Matina Kouvari of Harokopio University, Athens, Greece. "This finding was more evident in women. Prior research has shown that women tend to eat more plant-based foods and less animal-based products than men. But our study suggests that this does not guarantee healthier food choices and in turn better health status."Most dietary studies define plant-based diets simply as "vegetarian" or "low in meat," thereby treating all plant foods as equal. The unique aspect of this study was that it examined the type of plant-based foods consumed, in addition to the overall amount. Healthy plant-based products were principally the least processed foods, such as whole grains, fruits, vegetables, nuts, olive oil, and tea/coffee. Unhealthy plant-based products consisted of juices, sweetened beverages, refined grains, potatoes, and any kind of sweets (e.g. chocolate, Greek traditional desserts, etc.).The study examined the link between the amount and quality of plant-based foods and heart health over a 10-year period.In 2001 and 2002, the ATTICA study randomly selected a sample of adults living in Athens who did not have cardiovascular disease or other chronic conditions. The current analysis was conducted in 146 obese participants with normal blood pressure, blood lipids, and blood sugar. Diet was assessed using a questionnaire about usual habits in the previous year. It listed 156 foods and beverages commonly consumed in Greece, with photographs to help define portion sizes.Within a decade, nearly half of these obese participants had developed high blood pressure, high blood lipids, and high blood sugar -- a combination that is particularly risky for heart health.Men who consumed more plant-based foods were less likely to have this decline in health status. A trend was also observed in women, but it did not reach statistical significance.Regarding the quality of plant-based foods, healthier choices were linked with maintaining normal blood pressure, blood lipids, and blood sugar. Conversely, consuming unhealthy plant-based foods was associated with developing high blood pressure, high blood lipids, and high blood sugar. These relationships were stronger in women compared to men.Dr. Kouvari said: "Eating less meat is beneficial for heart health, particularly when it is replaced with nutritious plant foods such as whole grains, fruits, vegetables, nuts, and olive oil."She noted that the analysis was conducted in obese individuals and the findings should not be extended to other weight categories.
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Agriculture & Food
| 2,020 |
August 27, 2020
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https://www.sciencedaily.com/releases/2020/08/200827101821.htm
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Reduce insecticide spraying by using ant pheromones to catch crop pests
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Scientists at the Universities of Bath and Sussex have developed a new system that slowly releases ant pheromones to attract pests to an insecticide bait. This means that instead of spraying the whole crop with pesticides, traps can be placed in specific areas for more targeted protection.
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Leaf-cutting ants are major pest species of agriculture and forestry in many areas of the tropics causing an estimated $8 billion damage each year to eucalyptus forestry in Brazil alone.Traditional pesticides often degrade quickly and are not specific to particular pests, resulting in substantial wastage of pest control products, environmental contamination and harmful effects on other insects.The team of chemists and chemical engineers at Bath used molecular sponges called metal-organic frameworks (MOFs), to soak up the alarm pheromones of leaf cutter ants and then slowly release them to attract the insects to a trap.In addition to experiments, they used computational modelling to simulate the movement of the pheromone molecule inside the pores of the MOFs to predict which structures would give the optimum capacity and speed of release.They found that by altering the chemical groups within the basic framework structure, they could adjust the speed of release of the pheromones so that the chemicals could be released over a period of several months rather than days.Field trials of the system by University of Sussex researchers in a eucalyptus plantation in Brazil showed that the pheromone-loaded MOFs had the desired effect in attracting the ants to a trap.Professor Andrew Burrows, Head of the Department of Chemistry at the University of Bath and Professor of Inorganic Chemistry at the University's Centre for Sustainable and Circular Technologies, led the study that is published in the journal He said: "Insect pheromones have been used previously for attracting pests, but the trouble is they are quite volatile, so their effects don't last very long."Our metal-organic frameworks act as a kind of sponge where the pheromones can be encapsulated in the pores and then released slowly over time."Our proof-of-principle study shows that these materials are effective in delivering the pheromone and that the insects respond normally to it."This system could reduce the amount of pesticides sprayed on a crop and could be particularly useful for high value crops in small areas."We're currently looking at a range of other insect messenger chemicals including those that can be used to control moth pest species in UK fruit orchards."
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Agriculture & Food
| 2,020 |
August 26, 2020
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https://www.sciencedaily.com/releases/2020/08/200826131855.htm
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Current poultry food safety guidelines do not stop salmonella outbreaks
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Current poultry food safety guidelines for Salmonella, the leading cause of foodborne illness outbreaks, are inadequate. A new study conducted by Thomas Oscar, USDA Agricultural Research Service, "Salmonella prevalence alone is not a good indicator of poultry food safety," published in
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The poultry industry currently uses Salmonella prevalence or positivity rate as an indicator of food safety, but there are numerous other factors that influence the level of risk to public health. This study showed that even though other meats like ground chicken could have a lower Salmonella prevalence than ground turkey at meal preparation, they could pose a higher risk of salmonellosis if they are contaminated with higher numbers of more virulent serotypes of Salmonella.The current approach to food safety in the poultry industry consists of two pillars:These approaches are limited because pathogen prevalence is not the only risk factor for an outbreak and in the second pillar, harm to public health occurs before corrective action is taken.Present food safety reviews do not include data such as Salmonella serotype and virulence and number, incidence and extent of temperature abuse, incidence and extent of undercooking, incidence and extent of cross-contamination during meal preparation, food consumption behavior, and host resistance which are important risk factors for salmonellosis from ground turkey and other poultry products.Processing plants with a high prevalence of Salmonella on its poultry meat do not necessarily pose a higher risk of salmonellosis. Rather, poultry meat from a processing plant with a lower prevalence of Salmonella could pose a higher risk if:The study concludes that to increase food safety, a process risk model or computer model should be applied at the processing plant exit to integrate pathogen contamination data and post-processing risk factors to provide an objective description regarding the safety of individual lots of food before they are shipped to consumers. A more holistic approach to poultry food safety that considers Salmonella serotype, virulence, and number, and incidence and extent of temperature abuse, undercooking and cross-contamination, and food consumption behavior and host resistance is needed to better protect the public from foodborne pathogens like Salmonella.
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Agriculture & Food
| 2,020 |
August 26, 2020
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https://www.sciencedaily.com/releases/2020/08/200826083026.htm
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Crop breeding: Getting to the root of the problem
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Roots play a vital role in crop plants. They take up water and nutrients for the plant and keep it help firmly in the ground. But not all roots are the same.
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Different plants have different kinds of roots that help them survive in their environment. Two well-known examples are carrots and cactus. Carrots have a long taproot that penetrates deep into the soil. Cacti usually have shallow roots. These allow them to quickly soak up the little rainfall they receive in the desert.Can studying roots lead to better crops? It's a question that researchers from Pennsylvania State University set out to answer, focusing on beans. They know that crops like beans are critical for feeding a rapidly growing population."Grain legumes are critical for global food security, but achieve low yields in most areas," says Jonathan P. Lynch, a professor at Pennsylvania State University. "This is especially true in areas of the developing world that experience drought, heat, and low soil fertility."Breeding is a way to improve how crops perform in different environments. However, looking at the roots for beneficial characteristics for breeding is rarely done."Optimizing how plants get resources from the soil in stressful environments is important for increasing food production, but specific breeding objectives are ill defined," Lynch says. "We sought to test hypotheses about the link between root system architecture and life strategy in order to generate breeding targets."In their study, they analyzed the root systems of several kinds of beans and other legumes, like chickpeas. This allowed them to see tradeoffs and to determine what kind of root characteristics would perform better in certain environments. This can help plant breeders devise better plants.Roots explore both the topsoil and subsoil. Nutrients like phosphorus and potassium are more present in the topsoil, while water and nitrogen are usually deeper in the soil. They observed that many crops focus on one or the other of these soil layers, which results in a tradeoff."Root architecture is an important component of crop adaptation to environments where water and nutrients are lacking," Lynch says. "We suggest that root phenotypes capable of balancing topsoil and subsoil exploration would be useful."The researchers say that breeding programs could use trait-based selection on root characteristics they are interested in. They could then use various techniques to get well-adapted plants with stronger primary roots or longer root hairs, for example."Everyone knows that roots are important for crops, especially in poor soils and in dry conditions," Lynch adds. "However, very few crop breeders actively select for these root characteristics because it can be difficult. This paper is one of a growing number by our team and others showing how specific root characteristics are associated with crop resilience under stress."Lynch says his personal goal is to improve food security in developing nations. 850 million people are chronically malnourished around the world and with the human population expanding, the problem will only increase.Grain legumes have the potential to help address this problem because they are good for the soil and for humans. They take nitrogen from the air and make it usable in the soil and are rich in nutrients humans need like protein, iron, and zinc."It is important for us all to recognize the magnitude of the challenge represented by assuring food security for 10 billion people in a degraded global environment," Lynch says. "We must do what we can to help the next generation of agricultural scientists meet this challenge."
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Agriculture & Food
| 2,020 |
August 26, 2020
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https://www.sciencedaily.com/releases/2020/08/200826083014.htm
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Antagonistic genes modify rice plant growth
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Scientists at Nagoya University and colleagues in Japan have identified two antagonistic genes involved in rice plant stem growth. Their findings, published in the journal
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Longer, deepwater rice crops are planted in South Asia and West Africa to survive floods. Shorter paddy rice varieties are widely cultivated worldwide because they are easier to harvest.A key driver of plant growth is a hormone called gibberellic acid. It activates cell division in the stem tissue, causing the stem to lengthen. Breeders know they can control plant height by stimulating or inhibiting gibberellic acid activity. However, exactly how this works has been unclear.Bioscientist Motoyuki Ashikari has been studying the growth and evolution of rice for years. He and a team of researchers conducted genetic studies and identified two genes that are involved in regulating rice plant growth."We showed that gibberellic acid is necessary, but not enough, for stem elongation," says Ashikari.Interestingly, the two genes, called In the presence of gibberellic acid, ACE1 stimulates cell division and elongation of the stem's 'internode' sections in deepwater rice. The shorter paddy rice variety did not have a functional ACE1 gene, but it did have a homologous ACE1-like gene that was switched on to activate stem elongation at a different point of plant development.DEC1 was found in both the deepwater and paddy rice varieties. Its expression was reduced when deepwater rice plants were placed in deep water or treated with gibberellic acid. However, DEC1 continued to be expressed in paddy rice, even under the same conditions, suggesting this gene helps to suppress stem growth."We also found that ACE1 and DEC1 are conserved and functional in other plant species, like barley and other grasses, so our investigations improve understanding of the regulation of stem elongation in members of the Gramineae family that may have similar stem elongation mechanisms," says Ashikari.The team next aims to understand stem elongation at the molecular level by identifying factors that are associated with ACE1 and DEC1 expression.
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Agriculture & Food
| 2,020 |
August 25, 2020
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https://www.sciencedaily.com/releases/2020/08/200825160558.htm
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Researchers reveal molecular structures involved in plant respiration
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All plants and animals respire, releasing energy from food. At the cellular level, this process occurs in the mitochondria. But there are differences at the molecular level between how plants and animals extract energy from food sources. Discovering those differences could help revolutionize agriculture.
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"Plant respiration is a crucial process biologically for growth, for biomass accumulation," said Maria Maldonado, a postdoctoral researcher in the lab of James Letts, assistant professor in the Department of Molecular and Cellular Biology, College of Biological Sciences. "If you're thinking of crops, the extent to which they grow is related to biomass accumulation and the interplay between photosynthesis and respiration."In a study appearing in "For mammals or yeast, we have higher resolution structures of the entire electron transport chain and even supercomplexes, which are complexes of complexes, but for plants, it's been an entire black box," said Maldonado. "Until today."Figuring out the structure and functionality of these plant protein complexes could help researchers improve agriculture and even design better pesticides."Lots of pesticides actually target the mitochondrial electron transport chain complexes of the pest," said Letts. "So by understanding the structures of the plant's complexes, we can also design better-targeted pesticides or fungicides that will kill the fungus but not the plant and not the human who eats the plant."To make their food, plants utilize chloroplasts to conduct photosynthesis. But chloroplasts can pose a problem to scientists studying the molecular minutiae of the mitochondrial electron transport chain."Plants have mitochondria and they also have chloroplasts, which make the plant green, but the organelles are very similar in size and have very similar physical properties," said Maldonado.These similarities make it difficult to isolate mitochondria from chloroplasts in a lab setting. To get around this, the researchers used "etiolated" mung beans ("Mung beans are an oilseed such that they store energy in the form of seed oils and then the sprouts start burning those oils like its fuel," said Letts. Without chloroplasts the plants are unable to photosynthesize, limiting their energy streams.By separating mitochondria from chloroplasts, the researchers gained a clearer structural image of complex I and its subcomplexes."We used single-particle cryoelectron microscopy to solve the structure of the complexes after purifying them from mitochondrial samples," said Letts.With these structures, scientists can see, at the atomic level, how the building block proteins of complex I are assembled and how those structures and their assembly differs compared to the complexes present in the cells of mammals, yeast and bacteria."Our structure shows us for the first time the details of a complex I module that is unique to plants," said the researchers. "Our experiments also gave us hints that this assembly intermediate may not just be a step towards the fully assembled complex I, but may have a separate function of its own."The researchers speculated that complex I's unique modular structure may give plants the flexibility to thrive as sessile organisms."Unlike us, plants are stuck in the ground, so they have to be adaptable," said Letts. "If something changes, they can't just get up and walk away like we can, so they've evolved to be extremely flexible in their metabolism."With the structure of complex I now in hand, the researchers plan to conduct functional experiments. Further understanding complex I's functionality could open the doorway to making crop plants more energy efficient.
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Agriculture & Food
| 2,020 |
August 25, 2020
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https://www.sciencedaily.com/releases/2020/08/200825110758.htm
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Some of America's favorite produce crops may need to get a move on by 2045
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Record drought and heat have some farmers worried about where and when crops can be grown in the future, even in California where unprecedented microclimate diversity creates ideal growing conditions for many of the most popular items in America's grocery stores. A third of the vegetables and two-thirds of fruits and nuts consumed by Americans are now grown on more than 76,000 farms across the state, yet 20 years from now certain California regions may simply become too hot and dry for continued production.
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New research from Lawrence Berkeley National Laboratory (Berkeley Lab) shows that by the years 2045-2049 future temperatures will have more of an effect on when cool-season crops, such as broccoli and lettuce, can be grown than on where, while for warm-season crops (cantaloupe, tomatoes, carrots) the impact will be greater for where they can be grown versus when. The scientists describe pairing computer modeling with information about historic and ideal growing temperatures for five important California crops in their paper, "Projected temperature increases may require shifts in the growing season of cool-season crops and the growing locations of warm-season crops," which appeared in the journal "To ensure food security for California and the rest of the country, it's important to predict how future warming will affect California agriculture," said the paper's lead author Alison Marklein. "We need reliable information about how future climate conditions will impact our crops in order for the agricultural system to develop an adequate response to ensure food security. For instance, one major challenge when considering relocating crops is that growers have specialized knowledge of their land and crops. If crops can no longer be grown in their current locations, then the farmer has to either move to a new area or grow a different crop, which presents a practical and economic burden on the farmer."Now a scientist at UC Riverside, Marklein had previously led the project while completing a postdoctoral fellowship at Berkeley Lab and collaborating with Peter Nico, a study co-author and staff scientist in Berkeley Lab's Earth and Environmental Sciences Area. Scientists from the U.S. Department of Agriculture and UC Davis also contributed. Funded by the University of California's Global Food Initiative, the research represents a significant research focus for Berkeley Lab: sustainable agriculture. Another current Berkeley Lab study applies machine learning to developing microbial amendments that could replenish soils depleted of nutrients like carbon and phosphorus.In carrying out the study, the researchers first selected five annual crops that are produced more in California than any other state -- lettuce, broccoli, carrots, tomatoes, and cantaloupe. These nutrient-dense crops contributed 64% of the state's cash value of vegetable and melon crops in 2016 and are essential to food security, as evidenced by their place among the top vegetables and fruits donated to four studied California food banks.The team then obtained 15 years of air temperature data beginning in 1990 from locations across the state, as well as information about crop temperature thresholds -- or maximum and minimum air temperatures beyond which crop failure occurs -- and growing locations for each of the five crops going back seven years. They also considered a crop's optimal growing-season length: for example, broccoli requires four consecutive months of minimum 39 degrees Fahrenheit and maximum 95 degrees.Setting out to compare how each crop would do across California under different possible climate scenarios, one hot-dry and another cool-wet, the researchers looked at how higher temperatures may affect the crops in their historical growing locations. Next, they identified possibilities to expand any crop to a more ideal growing location based on that crop's temperature threshold, looking at all areas where that crop has not been grown, even where land had not previously been used for agriculture.Finally, the team calculated how much of the land historically used for growing each of the five crops can be maintained under future warming scenarios (hot-dry, cool-wet); how much of the land used would be untenable due to temperature rise; and how much land not formerly used for agriculture could potentially support each of the five crops in comparison to historical agricultural land where these crops have not yet been grown."We found differences in how warmer temperatures will affect the cool-season crops versus the warm-season crops," Marklein said. "For cool-season crops like broccoli and lettuce, it may be possible to extend their growing seasons. But it may become too warm to grow warm-season tomatoes where they have been historically farmed in summer, and may require moving them to milder climates warm enough for growing tomatoes under the new climate scenarios."The team found that both cool-season crops, broccoli and lettuce, are currently grown nearer to their lower temperature thresholds during fall and spring. The climate models predict an increase in winter temperatures above the minimum temperature threshold for both crops, suggesting that by mid-century these crops could also be grown into winter, even in areas where they have not historically been grown.The warmer temperatures in fall and spring suggest that tomatoes might benefit from a shift in growing season. But that could prove harder than it appears."Looking at the hot-dry future climate scenario, although temperatures in fall and spring are likely to increase as will summer temperatures, a shift in growing season isn't a viable solution because the summer temperatures are likely to exceed the critical temperatures for tomatoes," Marklein said. "Tomatoes need four consecutive months for their growing season, so the gap in the middle filled by summer makes this unfeasible."While it's true that some of the crops studied, tomatoes especially, will lose areas where they have been traditionally farmed due to future warming, there could be some ways to mitigate these potential challenges. For example, because their analysis focused on air temperature rather than crop temperature, in practice irrigation may be able to reduce some negative heat effects.In total, Marklein said this study gives agricultural planners a lot to think about. "This is really a first step in planning for future climate scenarios. This work could be used to help prioritize resources like cropland and water to maximize agricultural productivity and food security," she said. "It's critical to plan ahead for future warming scenarios, particularly in areas like California that feed the nation."
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Agriculture & Food
| 2,020 |
August 25, 2020
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https://www.sciencedaily.com/releases/2020/08/200825110744.htm
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Plant living with only one leaf reveals fundamental genetics of plant growth
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Clinging to the walls of tropical caves is a type of plant with a single leaf that continues to grow larger for as long as the plant survives. Researchers at the University of Tokyo hope that their study of this unusual species may help inspire future genetic tools to control the size of common crop plants.
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"We are pleased that we finally made a small breakthrough studying this plant," said Professor Hirokazu Tsukaya, who led the recent research project.The plant's scientific name, All Tsukaya first tried working with "The same curious biology that made the plants so interesting also made them challenging to study with new genetic tools being designed at the time for more common species with immediate agricultural or medical relevance. After a decadeslong hiatus while other molecular techniques developed, the project to understand "I believe ours is the only lab in the world currently studying this species," said Tsukaya.Understanding what makes "Luckily, another of our lab members, Assistant Professor Hiroyuki Koga, is a true professional at using the whole-mount system and he persisted to develop a suitable method for plants," said Tsukaya. Koga is the second author of the research publication and was able to perfect a technique to preserve entire three-week-old In plants with standard anatomy, the gene SHOOT MERISTEMLESS (STM) is expressed in cells at the growing tips of stems, referred to as the shoot meristem. Additionally, the gene ANGUSTIFOLIA3 (AN3) is expressed in very young leaves to promote the multiplication of cells that form the leaf."With our naked eye, we cannot see any shoot meristem in Instead of separating the location and timing of STM and AN3 gene expression, young "In Researchers state that understanding how unusual species like "We study
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Agriculture & Food
| 2,020 |
August 25, 2020
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https://www.sciencedaily.com/releases/2020/08/200825110717.htm
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Mineral dust ingested with food leaves characteristic wear on herbivore teeth
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Mineral dust ingested with food causes distinct signs of wear on the teeth of plant-eating vertebrates, which can differ considerably depending on the type of dust. This is what paleontologists at Johannes Gutenberg University Mainz (JGU) have discovered in a controlled feeding study of guinea pigs. As they report in the current issue of
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Over several weeks, the researchers fed 12 groups of guinea pigs with essentially the same plant-based pellets which contained different types and amounts (zero to eight percent) of natural mineral dust. The researchers then used a high-resolution microscope to examine the surface of the tooth enamel of each animal's molars. "We were able to identify some significant differences," added Winkler. For example, larger quartz particles (sand grains) caused severe abrasion on the enamel surface. The same applied to volcanic ash, which, due to its sharp edges, also produced a more irregular wear pattern. Small quartz particles generated a smooth, almost polished surface. On the other hand, there were no subsequent distinctive signs of wear features in the case of other particles. "Our results should improve the accuracy of diet reconstruction on the basis of fossil teeth," concluded Winkler. To date, it has been assumed that smooth tooth surfaces are related to the respective animal feeding on leaves that, unlike grass, leave hardly any traces of wear on the tooth surface; hence, this animal would have lived in a forest environment. However, it now seems possible that smooth tooth enamel wear patterns could have also developed because the animal ate grass, for example, to which tiny quartz grains were attached. These particles would have eliminated any irregularities on teeth, leaving an even, polished surface. "It is normal that animals ingest mineral dust along with their food," said Winkler. This is even more likely to be the case the drier the habitat is and the closer the food is ingested to the ground.The study was undertaken as part of the Vertebrate Herbivory research project led by Professor Thomas Tütken of the Institute of Geosciences at JGU, which is funded by a Consolidator Grant from the European Research Council (ERC). The study also involved researchers of the Clinic for Zoo Animals, Exotic Pets, and Wildlife at the University of Zurich, of Leipzig University, of the Max Planck Institute for Evolutionary Anthropology in Leipzig, and of the Center of Natural History at Universität Hamburg.
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Agriculture & Food
| 2,020 |
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