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August 25, 2020
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https://www.sciencedaily.com/releases/2020/08/200825110716.htm
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High human population density negative for pollinators
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Population density, and not the proportion of green spaces, has the biggest impact on species richness of pollinators in residential areas. This is the result of a study from Lund University in Sweden of gardens and residential courtyards in and around Malmö, Sweden. The result surprised the researchers, who had expected that the vegetation cover would be more significant.
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"We have found that, in cities, the higher the population density, the fewer species of wild bees and hoverflies we find in gardens and residential courtyards. We also see that areas with enclosed courtyards and tall buildings have fewer species of wild bees than areas with semi-detached and detached houses, even when there are large green spaces between the buildings," says Anna Persson, one of the researchers behind the study.It is believed that the result is due to two things, firstly, that tall buildings and enclosed courtyards constitute physical barriers for insects and secondly, that green environments in densely populated areas often are insufficient for pollinators, as they may only consist of for example a lawn and a few ornamental shrubs."Urban green spaces often look very different and the quality can vary a lot. A space can be green and still be a poor habitat for pollinators. In multi-family areas these spaces are usually simplified and maintained by an external contractor, compared to detached houses where there is often personal engagement and a greater variation of both plants and management practices," says Anna Persson.Another interesting discovery the researchers made was that urban gardens contain different species of wild bees than those found in agricultural landscapes."Therefore, the city complements the countryside," says Anna Persson, who contends that this is important knowledge, particularly in regions with intense farming, as this means that the city constitutes an important environment for the regional diversity of bees. It also means that measures for the conservation of bees are needed both in urban and rural areas, to reach different species.For hoverflies, however, the result was different -- the species found in urban areas were just a fraction of the species in rural areas, probably due to the fact that hoverfly larval habitats are scarcer in the city, for example, aquatic environments and plant debris.Urbanisation is one of the main causes of biodiversity decline. This is due both to urban land expansion and to denitrification through infill development. The researchers wanted to study which factor affected the species richness of pollinators to the greatest extent -- population density or vegetation cover. In addition, they wanted to find out if the built urban form had any effect on the species richness and what residential areas with high diversity of pollinators look like. The study was carried out by comparing species richness in areas with varying degrees of population density and vegetation cover -- in total, forty gardens and courtyards across nearly all of Malmö were studied. Researchers also made comparisons between gardens in the urban areas and the intensively farmed agricultural landscape surrounding Malmö."Pollinators are interesting and important to study in cities as they are crucial to the functioning of the ecosystem and, in addition, they are necessary for us to be able to achieve good harvests in our vegetable gardens and community allotments," says Anna Persson.She hopes the study will contribute new knowledge about how to plan and build cities in a way that reduces their negative impact on species richness."We show that the urban form is significant. By reducing the physical barriers between residential courtyards and by combining different kinds of built environments it is possible to benefit pollinators. In addition, we demonstrate that there is scope for improvements to the existing green spaces, particularly in areas with multi-family buildings. Green spaces in these areas are often of low quality, both for biodiversity and for human recreation. One way to upgrade them is to let them grow a little more 'wild', with less intensive maintenance and more native plants," she concludes.
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Agriculture & Food
| 2,020 |
August 24, 2020
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https://www.sciencedaily.com/releases/2020/08/200824165633.htm
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Climate change and land use are accelerating soil erosion by water
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Soil loss due to water runoff could increase greatly around the world over the next 50 years due to climate change and intensive land cultivation. This was the conclusion of an international team of researchers led by the University of Basel, which published the results from its model calculation in the scientific journal
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Soil erosion has far-reaching consequences. For example, it results in a loss of fertile soil, reduces agricultural productivity and therefore threatens the food supply for the world's population. Based on a global model, the new study now predicts how soil loss from water erosion is likely to change by the year 2070.Erosion is the process by which soil is carried away by wind and, above all, water. Intensive agricultural land use and agricultural methods that increase erosion, along with deforestation and overgrazing, are responsible for accelerating the loss of soil. In addition, in some parts of the world climate change is expected to further increase the amount of precipitation that will erode the soil.The researchers based their predictions on three scenarios that are also used by the Intergovernmental Panel on Climate Change (IPCC). The scenarios outline potential developments in the 21st century based on several different socio-economic postulations.All the scenarios including the effects of climate and land use change predict persistent water erosion, irrespective of the climate conditions in most of the roughly 200 countries that were included in the study. At the same time, the results indicate that climate change is the primary factor driving increased soil erosion.Depending on the scenario, the simulations predict that by 2070 soil erosion will increase significantly, by 30% to 66%, compared to 2015 figures. If agricultural practices do not change and measures are not taken to stop global warming, the study predicts that more than 28 billion additional metric tons of soil will be lost annually. This is around two-thirds more than the 43 billion tons estimated for 2015.The places most vulnerable to a sharp increase in erosion are low- to middle-income tropical and sub-tropical countries. The authors say that it will therefore be critical for countries in the Global South to promote more widespread use of sustainable agricultural practices."Soil erosion can be mitigated by sustainable land cultivation and the right policies," says Dr. Pasquale Borrelli, an environmental scientist from the University of Basel. "We hope that our predictions will help to identify the magnitude of the threat from erosion and allow policy-makers to develop effective measures to soften the impact."Researchers from the University of Basel, Kangwon National University, the UK Centre for Ecology & Hydrology, the Joint Research Centre of the European Commission and ETH Zurich all contributed to the study.
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Agriculture & Food
| 2,020 |
August 24, 2020
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https://www.sciencedaily.com/releases/2020/08/200824092034.htm
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Agricultural pesticides can affect prawns and oysters
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Researchers from the University's National Marine Science Centre have demonstrated that imidacloprid, a neonicotinoid insecticide, can impact the feeding behaviour of prawns in a laboratory environment, leading to nutritional deficiency and reduced flesh quality.
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"The sobering thing with this study is that it shows that the exposure of prawns to high concentrations of neonicotinoids can have such a significant impact," said lead author and PhD candidate Peter Butcherine whose study focussed on adult black tiger prawns."If they are not well managed, these chemicals have the potential to affect the productivity and sustainability of cultured and capture prawn fisheries."This latest study builds on Peter's earlier work reviewing the risk of neonicotinoid exposure to the shrimp aquaculture industry where he identified a significant problem with these water-soluble pesticides increasingly being detected in coastal waters worldwide.Prawns and shrimp are in the same animal phylum (category) as insects and therefore share similarities in the nervous system that is the main target for neonicotinoids, explained Professor Kirsten Benkendorff, co-author and Director of the National Marine Science Centre based at Coffs Harbour."This means prawns and shrimp are highly vulnerable if they become exposed to high levels of neonicotinoids, either through contaminated water or feed, which often contains plant-based material," Professor Benkendorff said.Imidacloprid is an agricultural insecticide used in Australia. Peter's research provides evidence that exposure to imidacloprid, at environmentally-relevant concentrations in food or water, leads to decreased food consumption and a loss of weight, as well as changes in the lipid composition of the flesh."This laboratory-based study indicates that cultured and wild prawns could be impacted in areas affected by high levels of neonicotinoid pesticide run-off," Peter said.Sydney rock oysters are also impacted by imidacloprid, according to the findings of a separate study co-authored by Professor Benkendorff."These two studies indicate both crustaceans and molluscs are vulnerable to insecticides, weakening their immune system and leaving them susceptible to disease," Professor Benkendorff said.Professor Benkendorff said further study is required to understand the range of pesticides in Australian waterways and their impacts on estuarine environments."Our research identifies the need for effective management of pesticide use and run-off from intensive agriculture in coastal areas with productive seafood industries," she said.
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Agriculture & Food
| 2,020 |
August 19, 2020
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https://www.sciencedaily.com/releases/2020/08/200819084959.htm
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Out of sync: Ecologists report climate change affecting bee, plant life cycles
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Bees and flowers seem inseparable harbingers of spring, but what happens when pollinators emerge later than their sources of nectar and pollen? Reporting on the first community-wide assessment of 67 bee species of the Colorado Rockies, ecologists Michael Stemkovski of Utah State University and Rebecca Irwin of North Carolina State University say "phenological mismatch," changing timing of life cycles between bees and flowers, caused by climate change, has the potential to disrupt a mutually beneficial relationship.
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"We analyzed time-series abundance data collected at 18 sites around the Rocky Mountain Biological Laboratory (RMBL) in the Elk Mountains of western Colorado during a nine-year, National Science Foundation-funded bee monitoring project," says Stemkovski, doctoral student in USU's Department of Biology and the USU Ecology Center.He and Irwin, senior author, along with colleagues from RMBL, University of Texas at Austin, Imperial College London, University of Manitoba, USDA-ARS Pollinating Insects Research Unit at USU, Central Texas Melittological Institute, Royal Saskatchewan Museum, Texas A&M University, Florida State University and University of Maryland, published findings in the August 19, 2020 issue of "We find bee emergence timing is advancing with snowmelt timing, but bee phenology -- timing of emergence, peak abundance and senescence -- is less sensitive than flower phenology," says Irwin, professor of applied ecology at NCSU. "Given global concerns about pollinator declines, the research provides important insight into the potential for reduced synchrony between flowers and their pollinators under climate change."Previous studies focused primarily on temperature, Stemkovski says, but this study probed the effects of topography and bee species traits, as well."Elevation played a large role in when bees start foraging, as well as the bees' functional traits, such as whether bees nested below or above ground, and the life stage in which they overwintered," he says. "We found all of these factors predicted bee emergence, but the most important factor was snowmelt timing."If bees begin foraging later than spring plants reach their flowering peak, consequences could be reduced abundance of pollinators, from limited sustenance, and reduced abundance of plants, from limited pollination."In the short-term, we expect mutualist species to suffer fitness losses," Stemkovski says. "In the long-term, bees and plants may be able to adapt and reestablish some synchrony, unless climate change outpaces the rate of adaptation."
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Agriculture & Food
| 2,020 |
August 18, 2020
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https://www.sciencedaily.com/releases/2020/08/200818175426.htm
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Cover crop mixtures must be 'farm-tuned' to provide maximum ecosystem services
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Penn State researchers, in a recent study, were surprised to learn that they could take the exact same number of seeds from the same plants, put them in agricultural fields across the Mid-Atlantic region and get profoundly different stands of cover crops a few months later.
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The study came to be known as "'farm-tuning' cover crop mixtures," noted researcher Jason Kaye, professor of soil biogeochemistry, who added that the findings are significant because they show the need to customize cover crop mixes to achieve desired ecosystem services, depending on soil and climatic conditions.Cover crop mixtures comprised of multiple species planted in rotation between cash crops provide a suite of benefits -- such as erosion reduction, weed control, and adding carbon and nitrogen to the soil. But it turns out, the expression of species in a mixture can differ greatly across locations.The study was novel due to its breadth and complexity. Researchers tracked a five-species cover crop mix planted over two growing seasons on eight organic dairy farms in Pennsylvania and New York and on research plots at Penn State's Russell E. Larson Agricultural Research Center. In the University's experimental plots, researchers manipulated cover crop expression with nitrogen inputs and planting dates to learn response of the various species to soil conditions and growing days."There have been very few studies like this -- especially looking at cover crop mixtures that are comprised of more than two species -- that analyze how species interact with each other, so I think it's important research," Kaye said. "There has been a misguided assumption that you plant a cover crop mixture and you get the same result wherever you put it."Commercial seed companies sell many pre-formulated seed mixtures, but they can also make customized mixes, Kaye said. "Our results show that with fixed, preformulated mixtures, what you grow is not always what you expect."In the study, all eight of the participating farmers seeded the standard mixture and a "farm-tuned" mixture of the same five species -- canola, Austrian winter pea, triticale, red clover and crimson clover -- with seeding rates adjusted to achieve farmer-desired services. At each location, researchers parsed out the effects of soil inorganic nitrogen and growing days on cover crop mixture expression.When soil inorganic nitrogen and growing days were high, they found, canola dominated the mixture, especially in the fall.From the same seed mixture, cover crop mixture expression varied greatly across farms, and researchers hypothesized that this variation was correlated with soil inorganic nitrogen concentrations and growing days, explained lead researcher Barbara Baraibar, who was a postdoctoral scholar in the Department of Plant Sciences when the study was conducted.Kaye's laboratory in the College of Agricultural Sciences has been conducting a continuous experiment evaluating the effectiveness of various cover crop mixtures since 2011.In findings recently published in The results show, Baraibar pointed out, that when soil inorganic nitrogen availability is high at the time of cover crop planting, highly competitive species can dominate mixtures, which could potentially decrease services provided by other species, especially legumes. And early planting dates can exacerbate the dominance of aggressive species.Based on this study, farm managers should choose cover crop species and seeding rates according to their soil inorganic nitrogen and planting dates to ensure the provision of desired services, she advised, suggesting that the real value of this research is that it provides usable information to farmers who want to take advantage of it."We wanted to have an experiment that would be real enough for farmers to be able to use the data," Baraibar said. "We wanted to know what actually happens when we plant these cover crop mixtures on many different farms that have different soils and different management. Our research paves the way for farmers and seed companies to use soil and climate knowledge to design custom seed mixes with predictable growth from the different species."The U.S. Department of Agriculture's National Institute of Food and Agriculture, Organic Research and Extension Initiative supported this work.
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Agriculture & Food
| 2,020 |
August 18, 2020
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https://www.sciencedaily.com/releases/2020/08/200818094046.htm
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Potential and constraints of reforestation for climate mitigation
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Reforestation is a promising nature-based climate solution. However, there are practical considerations beyond the suitability of land for planting trees, such as financial, land-use and operational constraints, which can limit its outcomes and thus need to be taken into account. A recent study led by researchers from the National University of Singapore (NUS) found that these constraints could limit the climate mitigation potential of reforestation in the Southeast Asian context. Understanding how these constraints operate helps inform the prioritisation of cost-effective reforestation and investment opportunities.
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Their findings were published in the journal During the annual meeting in Davos in January this year, the World Economic Forum launched an ambitious initiative to plant one trillion trees worldwide to restore biodiversity and fight climate change.Tree planting, and reforestation in general, have often been touted as a cost-effective nature-based solution to address climate change. This is due to the ability of trees and other natural vegetation to convert atmospheric carbon dioxide (COIn the study, the research team led by Professor Koh Lian Pin, who is from the NUS Department of Biological Sciences, estimated the climate mitigation potential of reforestation across Southeast Asia, and assessed the effects of biophysical, financial, land-use, and operational considerations on different constraint scenarios.The researchers found that 121 million hectares of land across Southeast Asia are suitable for reforestation, and could potentially contribute to climate mitigation at a rate of 3.4 gigatonnes of CO"However, only a fraction of that mitigation potential may be achievable if practical constraints are taken into account," noted Prof Koh, who is also Director of the NUS Centre for Nature-based Climate Solutions.One example is the many pockets of "barren land" in Southeast Asia that may actually be in use by farmers to grow crops for subsistence, or for sale in local markets. NUS postdoctoral research fellow Dr Zeng Yiwen, who is the first author of the paper, explained, "If we exclude these small farmlands, the available land for reforestation in Southeast Asia would be reduced to about 76 million hectares, and its climate mitigation potential would drop to 2.2 gigatonnes of COThe team noted that there may also be a need for reforestation sites to be near mature forests which could act as sources of seeds or seedlings that are critical for the reforestation process. Other considerations that the team took into account included the cost of reforestation and protection status."If we want to maximise the success of reforestation projects and restrict them to within two kilometres of existing intact forests, we would only be looking at about 33 million hectares of available land in the region, which would provide only 0.9 gigatonnes of COProf Koh explained, "The barriers to reforestation we have identified are not insurmountable. For example, by involving smallholder farmers in the reforestation process, such as through agroforestry or tree planting on their farms, climate mitigation potential can be realised while balancing trade-offs with food security and local livelihoods."Reforestation is an important nature-based solution, not only for climate mitigation, but also for the multiple co-benefits it provides, including biodiversity conservation, clean air and water, and poverty alleviation."A more complete and nuanced consideration of both the potential and limits of nature-based climate solutions is needed to inform climate policies and decisions that are scientifically sound, economically feasible and socially acceptable," he elaborated.
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Agriculture & Food
| 2,020 |
August 18, 2020
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https://www.sciencedaily.com/releases/2020/08/200818094044.htm
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New building block in plant wall construction
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University of Adelaide researchers as part of a multidisciplinary, international team, have uncovered a new biochemical mechanism fundamental to plant life.
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The research, published in Project leader, Professor Maria Hrmova, said the discovery contributes to important knowledge about how plant cell walls could be formed, structured and re-modelled."Plant cell walls perform a number of essential functions, including providing shape to the many different cell types needed to form the tissues and organs of a plant, intercellular communication, and they play a role in plant-microbe interactions, including defence responses against potential pathogens," Professor Hrmova said.Earlier research into the chemistry and function of the xyloglucan carbohydrates in plants had found that xyloglucan xyloglucosyl transferase enzymes are one of the key accelerants in the re-modelling of cell walls.It has only been through the development of the methodology used in this study, recombinant technology -- which makes it possible to isolate proteins in a pure state -- and the availability of defined carbohydrates, that it has been possible to observe the enzymatic reaction which occurs between the xyloglucan and pectin carbohydrates."When we were able to closely observe the substrate specificity of barley xyloglucan xyloglucosyl transferases, we discovered a chemical reaction, which results in the production of a hetero-polysaccharide (a carbohydrate composed of chemically distinct components). We could also examine these reactions at the molecular levels to define how these enzymes precisely work," Professor Hrmova said."It is one thing to be able to identify the different components of cell walls in plants, but that is not enough, we need to understand how they are formed and what they do, and this method of isolating pure proteins so they can be examined, allowed us to do just that," Professor Hrmova said."This discovery is a new building block in our understanding of how the cell wall could be constructed.""Once you understand how something is made, you can then look at constructing or de-constructing it in different ways," Professor Hrmova said."That is why fundamental knowledge on how these enzymes function is so valuable."The findings could have far-reaching implications for the sustainability of plant-based industries such as agriculture, horticulture, forestry for biofuels production and food and materials processing.To date the team have characterised four out of 36 xyloglucan xyloglucosyl transferases in barley, so there is still many more to examine, which could lead to further discoveries. Once this work has been completed for barley, the methodology could be applied to examining the cell walls of other crops such as wheat and rice."Plants are the world's largest renewable resource -- plants feed the world and they also produce energy in the form of biofuels," Professor Hrmova said.The knowledge could allow for the bioengineering of similar proteins involved in plant cell wall re-modelling to create higher quality foods and to learn how to de-construct plant cell walls to obtain biofuels.
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Agriculture & Food
| 2,020 |
August 18, 2020
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https://www.sciencedaily.com/releases/2020/08/200818094022.htm
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Bee neighborly -- sharing bees helps more farmers
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Many farmers are used to sharing big equipment -- like tractors and other costly machinery -- with neighboring farms. Sharing cuts costs, lowers the farmer's debt load, and increases community wellbeing. But big machinery might not be the only opportunity for farmers to reap the benefits of cost-sharing with their neighbors. New research suggests that the concept could also be applied to a more lively kind of agricultural resource -- wild bees.
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"Understandably, farmers with highly valuable crops don't always want to give up plantable space to create habitats for wild bees, especially if their crops could be pollinated by a neighbor's bees for free," said Eric Londsorf, lead scientist for the Natural Capital Project at the University of Minnesota's Institute on the Environment and lead author on the paper. "What we're proposing is that those farmers providing bee habitat could be rewarded for doing so, to the benefit of all."The research, published in "Bees don't pay attention to land boundaries," said Lonsdorf. "In the current system, farmers who choose to conserve habitat for bees on their lands are rarely recognized for the pollination benefits that they're also providing to their neighbors."Creating wild bee habitat on farms can be as simple as letting a small area of land remain wild, which provides bees with a familiar sanctuary amidst rows of crops. But there is little incentive for farmers to create space on their own lands if the costs are greater than the benefits they'd receive from the bees, which means that few farmers choose to sacrifice precious planting ground for bee habitat. "We know that wild bees are essential pollinators for many of our crops, but they also require space nearby the crops to live, so we need to know where and how to invest."The researchers found that if 40 percent of landowners were to provide space for wild bee habitat, those landowners would lose one million dollars themselves, but generate nearly two and a half million for their neighbors. If the landowners were able to work together so that those who benefitted paid into the cost of the bee habitat, then everyone could come out ahead. Especially relevant in the equation is the size and patterns of farms clustered together, which the researchers say is often overlooked in this kind of analysis."This is about tackling the tragedy of the commons, the idea that what's good for society isn't always what's good for a particular individual," said co-author Taylor Ricketts, Director of the Gund Institute for Environment at the University of Vermont and co-founder of the Natural Capital Project. "This research shows how and where working together can really increase the benefits for everyone, and just as important: where it won't."Ideally, the researchers would like to see their work help inform policies that encourage cooperation and resource sharing amongst farmers. They suggest that small groups of neighboring farmers come together, supported by local or national agricultural agencies like the United States Department of Agriculture, to decide how to allocate their land and bee habitats. This common-pool resource framework can be informed by the kind of analysis done by Lonsdorf and his colleagues so that farmers are able to make decisions that result in the highest benefits for the group.In an increasingly volatile economy where small savings can go a long way, investing in shared natural resources like pollinators could be a good choice for small-scale farmers who grow high-value crops. "It's an opportunity to overcome the tragedy of the commons," said Lonsdorf. "And our goal is to spark the conversation."
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Agriculture & Food
| 2,020 |
August 17, 2020
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https://www.sciencedaily.com/releases/2020/08/200817191752.htm
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Climate change mitigation not the primary motivator in regenerative ranching
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Regenerative ranching, a holistic approach to managing grazing lands, enhances ranchers' adaptive capacity and socioeconomic well-being while also providing an opportunity to mitigate climate change, a new study from Oregon State University has found.
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Regenerative ranching practices rebuild ecological processes, allowing ranchers to reduce reliance on products such as chemical herbicides, pesticides and fertilizers, which are significant sources of greenhouse gas emissions.While some science suggests that regenerative ranching can result in climate change mitigation through carbon drawdown into soils, that is not usually the driving factor behind ranchers' decision to adopt the practice, said the study's lead author, Hannah Gosnell, an OSU geographer who studies the human dimensions of climate change.Understanding what motivates ranchers to adopt carbon-friendly practices will play an important role in efforts to expand the use of managed grazing systems to reduce climate change impacts, said Gosnell, a professor in Oregon State's College of Earth, Ocean, and Atmospheric Sciences."What we found is that ranchers manage regeneratively for all these other benefits, and if there's some measureable soil carbon sequestration and it contributes to climate change mitigation, then that's icing on the cake," she said.The findings were just published in More than a third of the Earth's ice-free land surface is used for livestock grazing. Livestock production, while important to livelihoods across the world, is a significant source of greenhouse gas emissions, a key contributor to climate change, Gosnell said.Regenerative ranching is drawing increased interest as a potential climate change solution. Previous studies have suggested that these practices boost soil carbon sequestration, a process by which carbon dioxide from the atmosphere is transferred into and stored in soil through vegetation, and increase resilience to drought, which help ranchers both mitigate and adapt to the effects of climate change, Gosnell said.To better understand ranchers' motivations and interest in regenerative agriculture practices, Gosnell interviewed ranchers in the United States and Australia about the perceived benefits and challenges of adopting the practices.She and her colleagues found that the transition to regenerative ranching is often difficult because the practices require a thorough understanding of the fundamental ecosystem processes involved. They also found that offering incentives such as cash payments are not the most promising way to convince ranchers to make the switch, since the practice requires a paradigm shift in thinking along with a new set of practices."It's hard to transition to regenerative ranching because it requires such a deep commitment," Gosnell said. "If you want ranchers to make the switch, paying them is likely not motivation enough."The most common benefit of regenerative agriculture mentioned by the ranchers interviewed was the increase in deep ground cover, which increases soil carbon sequestration and leads to increased forage for livestock and greater resilience to stressors such as droughts, floods or freezing temperatures. Because ranchers using regenerative practices were not dependent on expensive chemicals, they also were less vulnerable to financial shocks and stressors, which in turn increased their resilience, Gosnell said.Improved water retention, increased soil fertility and other benefits from regenerative ranching motivate ranchers to continue using the approach once they adopt it, through a process of self-amplifying positive feedbacks, she said."As a result of their new practices, ranchers see less bare ground, more native perennials, more biodiversity and more forage for their cattle, all without use of chemicals," she said. "This inspires them to continue with regenerative practices, which then leads to more ecological improvement, better economic returns and more positive feedback for the rancher."There are few opportunities for ranchers to be paid through carbon markets, a trading program where those who emit carbon purchase "offsets" or credits from an entity that is reducing its carbon footprint or increasing carbon sequestration. Also, because the approach takes tremendous dedication, cash incentives alone may not suffice, Gosnell said."Putting a price on carbon and incentivizing practices with payments is probably necessary, but certainly not sufficient for the approach to scale up," Gosnell said. "A broader shift in practices will likely require a 'bottom-up' approach involving networks of like-minded individuals contributing to cultural change within agriculture and the cultivation of new markets for regenerative products."Research, outreach and education is also needed to help ranchers develop a deep understanding of the ecological processes that makes the switch to regenerative ranching effective, she said."This is a low-cost, low-tech, natural climate solution, and it can be a really effective and important one," she said. "But it is hard for ranchers to transition to because it requires a deep understanding of fundamental ecological processes and adoption of a new set of management tools."
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Agriculture & Food
| 2,020 |
August 17, 2020
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https://www.sciencedaily.com/releases/2020/08/200817104323.htm
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More healthful milk chocolate by adding peanut, coffee waste
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Milk chocolate is a consumer favorite worldwide, prized for its sweet flavor and creamy texture. This confection can be found in all types of treats, but it isn't exactly health food. In contrast, dark chocolate has high levels of phenolic compounds, which can provide antioxidant health benefits, but it is also a harder, more bitter chocolate. Today, researchers report a new way to combine milk chocolate with waste peanut skins and other wastes to boost its antioxidant properties.
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The researchers will present their results today at the American Chemical Society (ACS) Fall 2020 Virtual Meeting & Expo."The idea for this project began with testing different types of agricultural waste for bioactivity, particularly peanut skins," says Lisa Dean, Ph.D., the project's principal investigator. "Our initial goal was to extract phenolics from the skins and find a way to mix them with food."When manufacturers roast and process peanuts to make peanut butter, candy and other products, they toss aside the papery red skins that encase the legume inside its shell. Thousands of tons of peanut skins are discarded each year, but since they contain 15% phenolic compounds by weight, they're a potential goldmine of antioxidant bioactivity. Not only do antioxidants provide anti-inflammatory health benefits, they also help keep food products from spoiling."Phenolics are very bitter, so we had to find some way to mitigate that sensation," Dean says. In fact, the natural presence of phenolic compounds is what gives dark chocolate its bitterness, along with less fat and sugar compared to its cousin milk chocolate. Dark varieties are also more expensive than milk ones because of their higher cocoa content, so the addition of a waste like peanut skins provides similar benefits for a fraction of the price. And peanut skins are not the only food waste that can enhance milk chocolate in this way; the researchers are also exploring the extraction and incorporation of phenolic compounds from used coffee grounds, discarded tea leaves and other food scraps.To create their antioxidant-boosted milk chocolate, Dean and her team of researchers at the U.S. Department of Agriculture's (USDA's) Agricultural Research Service worked with peanut companies to obtain the peanut skins. From there, they ground the skins into a powder, and extracted the phenolic compounds with 70% ethanol. The lignin and cellulose left behind can be used in animal feed as roughage. They also worked with local coffee roasters and tea producers to obtain used coffee grounds and tea leaves, using a similar methodology to extract the antioxidants from those materials. The phenolic powder is then combined with maltodextrin, a common food additive, to make it easier to incorporate into the final milk chocolate product.To make sure their new confection would pass gastronomic muster, the researchers created individual squares of chocolate with concentrations of phenolics ranging from 0.1% to 8.1% and had a trained sensory panel taste each one. The goal was to have the phenolic powder be undetectable in the flavor of the milk chocolate. The taste-testers found that concentrations over 0.9% were detectable, but incorporating the phenolics at 0.8% resulted in a good compromise of a high level of bioactivity without sacrificing flavor or texture. In fact, more than half of the taste testers preferred the 0.8% phenolic milk chocolate over the undosed control milk chocolate. This sample had higher chemical antioxidant activity than most dark chocolates.While these results are very promising, Dean and team also acknowledge that peanuts are a major food allergy concern. They tested the phenolic powder made from the skins for presence of allergens, and while none were detected, they say that a product containing peanut skins should still be labeled as containing peanuts.Next, the researchers plan to further explore the use of peanut skins, coffee grounds and other waste products into additional foods. In particular, Dean is hoping to test whether the antioxidants in peanut skins extend the shelf life of nut butters, which can go rancid quickly because of their high fat content. While commercial availability of their boosted chocolate is still a ways off and subject to corporate patents, they hope that their efforts will eventually lead to a better milk chocolate on supermarket shelves.
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Agriculture & Food
| 2,020 |
August 17, 2020
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https://www.sciencedaily.com/releases/2020/08/200817104300.htm
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Scientists further cowpea research--boosting canopy CO2 assimilation, water-use efficiency
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Crops grow dense canopies that consist of several layers of leaves -- the upper layers with younger sun leaves and the lower layers with older shaded leaves that may have difficulty intercepting sunlight trickling down from the top layers.
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In a recent study published in RIPE, which is led by the University of Illinois, is engineering crops to be more productive by improving photosynthesis, the natural process all plants use to convert light energy to produce biomass and yields. RIPE is supported by the Bill & Melinda Gates Foundation, the U.S. Foundation for Food and Agriculture Research (FFAR), and the U.K. Government's Department for International Development (DFID). One of the target crops of the RIPE project is cowpea.Cowpeas, commonly known as black-eyed peas in the U.S., are one of the oldest domesticated crops in the world, responsible for feeding more than 200 million people per day."They are a staple crop in Africa, providing a source of protein for humans and livestock, and restoration of soil nutrition through nitrogen fixation," said Lisa Ainsworth, a research plant physiologist with the U.S. Department of Agriculture, Agricultural Research Service (USDA-ARS).The RIPE team screened 50 cowpea genotypes from a multi-parent advanced generation inter-cross (MAGIC) population for canopy architecture traits, canopy photosynthesis, and water-use efficiency by using a canopy gas exchange chamber. This chamber was used to measure the rate by which plants would convert CO"Since sub-Saharan Africa is the region where important yield gaps persist, it is crucial that we develop a high yielding crop that can be easily grown there," said first author Anthony Digrado, a USDA-ARS postdoctoral researcher in Ainsworth's lab based at Illinois. "That is to say that water-use efficiency should be taken into serious account when developing new varieties for sub-Saharan African countries that are challenged by access to water in several regions."The team used Principal Component Analysis (PCA) models to first group the 50 MAGIC genotypes into five general canopy architectural types to study plant traits, including leaf area index, leaf greenness, and canopy height and width. This analysis gave researchers the ability to gather an overview of the traits, or combinations of traits, that could be modified to have the strongest impact on canopy photosynthesis to maximize growth.Canopy architecture contributed to 38.6 percent of the variance observed in canopy photosynthesis. Results showed that in canopies with lower biomass, the major limitation to canopy photosynthesis was leaf area; however, in higher biomass canopies, the major limiting factor was, instead, the light environment. Canopies with high biomass have greater canopy photosynthesis when leaves at the top of the canopy have lower chlorophyll content.Overall, canopy architecture significantly affected canopy photosynthetic efficiency and water-use efficiency, suggesting that optimizing canopy structures can contribute to yield enhancement in crops."Water-use efficiency refers to the amount of COThe MAGIC cowpea population that the team used matches this criteria for an ideal crop, especially one to be grown in the drought conditions of Africa. However, research on how canopy architecture affects canopy CO"There is still a lot to do to improve cowpea yields and much more research is needed," Digrado said. "But this work has established that variation exists that can be used to improve productivity and efficiency of an important food security crop."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.
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Agriculture & Food
| 2,020 |
August 14, 2020
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https://www.sciencedaily.com/releases/2020/08/200814131023.htm
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Decline in US bird biodiversity related to neonicotinoids, study shows
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Bird biodiversity is rapidly declining in the U.S. The overall bird population decreased by 29% since 1970, while grassland birds declined by an alarming 53%.
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Valuable for so much more than flight and song, birds hold a key place in ecosystems worldwide. When bird numbers and varieties dwindle, pest populations increase and much-needed pollination decreases. Those examples alone negatively impact food production and human health.Likely reasons for the far-reaching and devastating declines include intensified agricultural production, use of pesticides, conversion of grassland to agricultural land, and climate change. A new study from University of Illinois points to increased use of neonicotinoid insecticides as a major factor in the decline, says Madhu Khanna, distinguished professor in agricultural and consumer economics at U of I and co-author on the paper, published in Khanna says numerous studies have shown neonicotinoids -- nicotine-based pesticides -- negatively affect wild bees, honey bees, and butterflies, but large-scale studies on the pesticide's impact on birds have been limited. She speaks more about the topic in a podcast from the Center for the Economics of Sustainability at Illinois."This represents the first study at a national scale, over a seven-year time period, using data from hundreds of bird species in four different categories -- grassland birds, non-grassland birds, insectivores, and non-insectivores," she says."We found robust evidence of the negative impact of neonicotinoids, in particular on grassland birds, and to some extent on insectivore birds after controlling for the effects of changes in land use."Khanna and co-authors Yijia Li, a graduate student at U of I, and Ruiqing Miao, assistant professor at Auburn University, analyzed bird populations from 2008 to 2014 in relation to changes in pesticide use and agricultural crop acreage.The authors found that an increase of 100 kilograms in neonicotinoid usage per county-a 12% increase on average-contributed to a 2.2% decline in populations of grassland birds and 1.6% in insectivorous birds. By comparison, the use of 100 kilograms of non-neonicotinoid pesticides was associated with a 0.05% decrease in grassland birds and a 0.03% decline in non-grassland birds, insectivorous birds, and non-insectivorous birds.Since impacts accumulate, the authors estimate that, for example, 100 kilograms neonicotinoid use per county in 2008 reduced cumulative grassland-bird populations by 9.7% by 2014. These findings suggest that neonicotinoid use has a relatively large effect on population declines of important birds and that these impacts grow over time.According to the study, the adverse impacts on bird populations were concentrated in the Midwest, Southern California, and Northern Great Plains.The researchers say the effect of neonicotinoids could result directly from birds consuming treated crop seeds, and indirectly by affecting the insect populations they feed on. Consumption of just a few seeds is enough to cause long-term damage to the birds' reproduction and development.The study included data on bird population and species diversity from the North American breeding bird survey, a comprehensive database with data from about 3,000 bird routes across the United States. The researchers correlated the bird data with pesticide use, as well as satellite data on agricultural crop acreage and urban land use.They examined whether intensified agricultural production and conversion of grassland to agricultural land also contributed to the bird decline. Results showed a small negative effect on grassland birds related to cropland expansion, but no significant effect on other types of birds.While the use of other pesticides has been flat or declining, neonicotinoid usage has grown exponentially over the past two decades. Neonicotinoids are considerably more toxic to insects and persist longer in the environment, the researchers note."This research provides compelling support for the re-evaluation of policies permitting the use of neonicotinoids by the U.S. Environmental Protection Agency by incorporating considerations of the implications of these pesticides for bird habitats," the authors conclude.The project was supported by Hatch funding from the U.S. Department of Agriculture (USDA), National Institute of Food and Agriculture (NIFA).
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Agriculture & Food
| 2,020 |
August 14, 2020
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https://www.sciencedaily.com/releases/2020/08/200814131008.htm
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Source of pathogen that causes bitter rot disease
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Fungal spores responsible for bitter rot disease, a common and devastating infection in fruit, do not encounter their host plants by chance. Turns out, they have a symbiotic association with the plant, often living inside its leaves.
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The new way of looking at the fungal pathogen, Colletotrichum fioriniae, as a leaf endophyte -- bacterial or fungal microorganisms that colonize healthy plant tissue -- was the outcome of a two-year study conducted by researchers in Penn State's College of Agricultural Sciences.According to Phillip Martin, a doctoral candidate in plant pathology, the findings, which were published recently in the journal Colletotrichum fioriniae causes diseases, often called anthracnoses, in more than 100 fruit and vegetable plants, including apple, peach, pear and strawberry. The fungus infects the fruit under warm and wet conditions and causes brown, sunken lesions; occasionally, orange spores will be seen on the surface.The disease is of concern to the Pennsylvania apple industry, which produces 400 million to 500 million pounds of apples per year. The state ranks fourth in the nation for apple production, per statistics from the U.S. Department of Agriculture."The research was based on the idea that if we can determine where the spores are coming from, then maybe we can eliminate the source and break the bitter rot disease cycle," said Martin, who carried out the study under the guidance of Kari Peter, associate research professor of tree-fruit pathology. "Unfortunately, from this perspective, many of the spores come from leaves, including apple leaves, and from trees and shrubs that are everywhere in Pennsylvania."Previously, the spores in question were thought to originate mostly from diseased fruits and twigs. However, even when infected fruits and twigs were removed from a tree, the disease, while reduced, often still was present, a circumstance that puzzled scientists.The research, which took place in 2018 and 2019, focused on apples and involved the placement of rain-splash spore traps in orchards at Penn State's Fruit Research and Extension Center, at Hollabaugh Bros. Inc. fruit and vegetable farm, and at a satellite location in Arendtsville, all of which are located in Adams County. Traps also were placed in two forested areas -- comprised mostly of deciduous trees -- near the orchards.Based on previous research that indicated that Colletotrichum fioriniae could survive on leaves, the team collected more than 1,000 leaves of apple and of 24 forest plant species. The leaves were disinfected to kill fungi on the leaf surface, frozen to kill the leaves and incubated to allow the fungi inside of the leaves to grow out and sporulate.This test found Colletotrichum fioriniae in more than 30% of leaves sampled, with most spores coming from the forest samples. In orchards that were managed with fungicides, up to 8% of apple leaves were infected with the fungus. In the untreated orchard, Martin said, the spores were abundant, meaning they were found in 15-80% of the leaves. The infections did not seem to be causing any leaf diseases, however."While unexpected, these findings did explain why growers struggle with bitter rot even when they remove all diseased fruits and twigs -- the fungus was living in the leaves during the season," Martin said. "The fungus was present in all the tested orchards and could not be traced to infection from a nursery, which makes sense since the initial infections likely are coming from surrounding forests and fence rows."Since the fungus is abundant in the forest canopy, eradication from nearby areas would be impractical, Martin added. However, the spatial limitations of rain-splash dispersal mean that forests are not regular sources of fungus spread; they likely serve only as primary introduction sources during extreme rain and wind events, after which the fungus becomes established in agricultural areas."Our study changes how we think about this fungus," Martin said. "While it may not supply quick fixes, it provides the basis for further research aimed at developing better management techniques, such as selecting resistant cultivars and breeding for genetic resistance."Peter agreed. "Although it's exciting to understand that Colletotrichum fiorinae's niche in the environment is more sophisticated than we had appreciated, it does make managing bitter rot in apple orchards less straightforward," she said. "As researchers, we can view this is an opportunity to think outside the box and to be creative in figuring out a sustainable bitter rot management strategy."In the meantime, Martin noted, disease-management tactics stay the same. "We don't believe most spores are overwintering in the leaves," he said. "Growers should continue to remove the infected fruits and twigs to help reduce disease spread season to season."
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Agriculture & Food
| 2,020 |
August 14, 2020
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https://www.sciencedaily.com/releases/2020/08/200814101515.htm
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A new role for a well-known molecule as a plant hormone
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Researchers at the University of Maryland (UMD) have discovered an entirely new role for a well-known plant molecule called ACC, providing the first clear example of ACC acting on its own as a likely plant hormone. Just like in humans and animals, hormones in plants carry messages to signal and trigger essential processes for plant health and functionality, from reproduction to defense. Without these processes, crops can't reproduce and thrive to provide the food we need to feed a growing global population.
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In a new publication in "There are several novel things about this paper," explains Caren Chang, UMD. "But the main impact is that it introduces a new plant growth regulator or plant hormone, alongside a small handful of other publications. It isn't a newly identified molecule, but it has never been thought of before as a plant hormone, only as the precursor to ethylene."Chang, a professor in Cell Biology & Molecular Genetics and affiliate professor of Plant Science & Landscape Architecture supported by the Maryland Agricultural Experiment Station (MAES), explains that ethylene is one of the five major plant hormones and has been studied for over a century. It is important for many processes that are vital to plant health and crop production, including fruit ripening, stress responses to flooding and drought, plant disease defenses, germination, and flowering."In much of the research, ACC has been used in place of ethylene, knowing that it's a precursor that plants convert into ethylene. This is because ACC is easy to work with in powder form and can even be sprayed on the plant, but working with ethylene is very difficult because it is a gas. So researchers have used ACC for decades in place of ethylene, and the literature would interpret the observed responses as ethylene responses. What our paper shows is that an ACC response is not necessarily an ethylene response. While ethylene is an important plant hormone with its own set of functions, some of these responses that have been attributed to ethylene through ACC may actually be separate ACC responses, acting as a growth regulator or hormone itself."This finding opens the door for many papers across decades of research, as well as textbooks and future education on plant hormone responses, to be revised in the event that ACC is actually triggering important plant processes previously attributed to ethylene.According to Chang, the paper also presents advances in plant reproduction. "In the plant reproduction field, there are many steps that are critical in pollination, and one of these steps requires the pollen to reach the ovules to actually produce a seed," says Chang. "Our paper shows that ACC signaling in the ovule is involved in getting the pollen tube to turn and effectively deliver the pollen, which makes it essential for seed production. It's probably the first example showing how the maternal ovule tissue actually helps attract the pollen tube." And this isn't a small effect, Chang stresses. "The seed number pretty much doubles in the presence of ACC. There is potential here to improve the seed number, which can increase food production in certain crops and have an impact on food security long-term."Led by José Feijó, another professor in Cell Biology & Molecular Genetics and affiliate professor of Plant Science & Landscape Architecture, another major finding of this paper shows clear connections between human, animal, and plant hormone signaling pathways by identifying a potential receptor for ACC activity."The most interesting parallel is cell-cell communication," explains Feijó. "Animal glutamate receptors are proteins which are needed for information to jump from one neuron to the next, either through an electric impulse or through calcium signaling, which is essential for things like memory. Problems in the processes mediated by glutamate receptors are known to be related to neurodegeneration and depression."Chang adds, "These receptors have been found in the human nervous system, and neuroscientists have been studying them for drug development to treat nervous system issues like depression. They found that ACC can actually affect the nervous system in humans. So we decided to look for the same receptors, named glutamate-like receptors (GLRs) in plants, to see if they respond to ACC in plants. We found that ACC can actually affect GLRs in plants as well."This finding opens an entirely new avenue of research in plant biology and points to similarities in plants and humans that are currently not well understood. "In plants, GLRs all seem to convey functions related to communication, either to bring male and female genes into an egg, or in pathogen or stress alert systems and defenses," says Feijó."Emerging trends suggest that GLRs underlie long distance electric signaling through the plant vascular system, where injury to tissues in one leaf inform the whole plant to create nasty substances to deter insects. All these lines seem to point into the existence of electric communication within plant tissues and organs, and that these functions involve GLRs. This is an interesting parallel evolution of a function for glutamate receptors as they evolved to be associated with the animal nervous systems to perform similar functions."With ACC as a new candidate activating GLRs and all the newly discovered roles it is playing as a plant hormone, Chang and the team are excited about the directions this work can go. "There is still a lot of research to be done to see how this is all happening and can be used in different crops, but all that new research can happen now."
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Agriculture & Food
| 2,020 |
August 13, 2020
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https://www.sciencedaily.com/releases/2020/08/200813155823.htm
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Cover crop roots are an essential key to understanding ecosystem services
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To judge the overall effectiveness of cover crops and choose those offering the most ecosystem services, agricultural scientists must consider the plants' roots as well as above-ground biomass, according to Penn State researchers who tested the characteristics of cover crop roots in three monocultures and one mixture.
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"Almost everything that we know about the growth of cover crops is from measuring the above-ground parts and yet some of the benefits that we want to get from cover crops come from the roots," said researcher Jason Kaye, professor of soil biogeochemistry. "This study shows us that what we see above ground is sometimes -- but not always -- reflective of the benefits below ground."Cover crops are widely used to increase the quantity of organic carbon returned to the soil between cash crops such as corn, wheat and soybean, as well as to limit erosion and to fix or add nitrogen to the soil. Cover crop roots are known to play an essential role in increasing soil organic carbon levels, Kaye noted, but the root traits that impact carbon levels vary widely among cover crop species, and this variation has yet to be characterized.Recently, Kaye pointed out, cover crop mixtures have expanded in popularity as a way to increase the diversity of cover crop benefits. His research group in the College of Agricultural Sciences has been conducting a continuous experiment evaluating the effectiveness of various cover crop mixtures since 2011.In the latest study, conducted at Penn State's Russell E. Larsen Agricultural Research Center at Rock Springs, recently published in They tested the quantity, quality and spatial distribution of those cover crop roots to learn about root-trait variation among species, and how that variation impacts mixture design. They took root cores from in-row and between-row locations to a depth of about 16 inches in both fall and spring from cover crops planted after winter wheat.Researchers also assessed cumulative carbon inputs for the entire rotation to determine cover crop and cash crop root carbon contributions. They measured the vertical and horizontal distribution of root biomass, the ratio of root biomass to aboveground biomass -- known as the root-to-shoot ratio -- and related that to the amount of nitrogen in the plants to determine how these parameters differed between cover crop treatments.Cover crop mixtures increased total carbon inputs to soil because they simultaneously had high root and shoot inputs and they promoted higher carbon inputs from corn crop residues, Kaye explained."The corn crop was more productive following the mixtures than following grasses, and while we harvest a lot of that productivity, some gets left behind in residues," he said. "I think this is really interesting because it shows that the effect of cover crops on soil carbon are not just related to their own roots and shoots, but also how they affect growth of the cash crops."The study revealed root trait differences among the three important winter annual cover crops, canola, crimson clover and triticale, lead researcher Joseph Amsili pointed out. The research uncovered several important root traits, he added, including the high root-to-shoot ratio and large production of between-row roots for triticale, which is a hybrid of winter wheat and cereal rye."The five-species mix was associated with increased quantity and distribution of roots compared to a crimson clover monoculture, which shows the benefits of combining legumes that have limited root biomass with brassica and grass species that produce greater root biomass, but provide more nitrogen," said Amsili. Now an extension associate in the Soil and Crop Sciences Section in the School of Integrative Plant Sciences at Cornell University, he was a graduate student in the Department of Ecosystem Science and Management at Penn State when he spearheaded the research.The study is important because the increased knowledge of cover crop root traits it yielded improves the understanding of the linkages between root traits and the services cover crops provide, Kaye explained. Going forward, he expects to find cover crops and design cover crop mixtures that deliver unexpected ecosystem benefits and added boosts to cash crops that follow."We'll now be able to think about what we want to occur in the soil and then design mixtures that have the root traits that are best able to provide those benefits," he said. "Advancing research on cover crop root traits serves as a strong foundation for designing mixtures with complementary root traits. I envision that we will exploit lots of different cover crop plants for different traits, both above and below ground."This research was funded by the U.S. Department of Agriculture's National Institute of Food and Agriculture, Organic Research and Extension Initiative.
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Agriculture & Food
| 2,020 |
August 13, 2020
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https://www.sciencedaily.com/releases/2020/08/200813123612.htm
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Flavonoids' presence in sorghum roots may lead to frost-resistant crop
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Flavonoid compounds -- produced by the roots of some sorghum plants -- positively affect soil microorganisms, according to Penn State researchers, who suggest the discovery is an early step in developing a frost-resistant line of the valuable crop for North American farmers.
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That is important because sorghum is a crop that can respond to climate change because of its high water- and nitrogen-use efficiency, according to Surinder Chopra, professor of maize genetics, and Mary Ann Bruns, professor of soil microbiology. A close relative to corn, it is the fifth most valuable cereal crop globally."Sorghum can be used for human food and animal feed and also can be grown as a bioenergy crop, producing more ethanol than corn when grown on marginal lands," they said. "Sorghum is better adapted than corn to stresses such as drought, salinity and heat. But increased sorghum production requires increasing its tolerance to chilling and frost stress, and this is especially true for the northeastern U.S."To reach its full potential, sorghum needs to grow five months after being planted in the first week of June. If a frost occurs in early October -- which is not unusual in the U.S. Northeast -- farmers can be devastated. Because sorghum is so sensitive to being chilled, even a mild frost or an early cold snap can kill the crop.Earlier studies by Chopra's research group in the College of Agricultural Sciences showed that sorghum produces potent flavonoids in its leaves when exposed to stresses such as fungi, insect feeding or frost. These flavonoids can allow the plant to adapt and survive. Bruns group has been working on understanding soil microbiomes in various stressed ecosystems.Together, the researchers are testing whether interactions between those flavonoids and microorganisms in the root zone can lead to the development of sorghum varieties and compatible soil microbial additions to provide resistance to cold and frost. A collaborative effort between the two research groups enables them to connect the prevalence of plant-associated microbiomes, plant genetics and flavonoids.In this study, researchers found evidence that plant genetic variation influences root flavonoids and the composition of the soil microbial community, and that low temperatures affect these relationships. In findings recently published in "We think that the flavonoids can provide the needed tolerance against the stress of cold and frost," Bruns and Chopra said. "In addition, certain microorganisms present in the soil can interact with flavonoids to provide adaptability to the plant when it perceives cold or frost above ground."The researchers grew selected lines of sorghum at Penn State's Russell E. Larson Agricultural Research Center at Rock Springs from seeds they acquired from the Grain, Forage and Bioenergy Research Laboratory maintained by the U.S. Department of Agriculture's Agricultural Research Service in Lincoln, Nebraska.Of those "near-isogenic" lines of sorghum -- alike except for two genes involved in the production of flavonoids -- one set of lines inherently produced flavonoids, the second set lacked genes to produce flavonoids, and the third type only produced flavonoids when the plants were exposed to stress such as frost and fungal pathogens.Researchers analyzed the community of microorganisms in the soils surrounding the roots to see if the presence or absence of flavonoids in the roots of some of the sorghum plants impacted communities of fungi and bacteria. Lead researcher Mara Cloutier, doctoral candidate in soil science and biogeochemistry, led the evaluation of microbiomes in the vicinity of the roots before and after a late-season frost.The researchers analyzed roots for total flavonoids, total phenolics and antioxidant activity to determine whether sorghum genetic variation influenced root flavonoid concentrations and soil microbial communities. The researchers wanted to identify how frost affected these relationships."We found that a greater number of bacterial strains were correlated with total flavonoids compared with fungal species," she said. "Collectively, this study provides evidence that plant genetic variation influences root flavonoids and the soil microorganism community composition in the vicinity of the plant roots, and that these relationships are affected by frost."Also involved in the research were Debamalya Chatterjee, Dinakaran Elango and Jin Cui, graduate students in plant science.The Sun Grant Initiative and the U.S. Department of Agriculture's National Institute of Food and Agriculture funded this research.
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Agriculture & Food
| 2,020 |
August 13, 2020
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https://www.sciencedaily.com/releases/2020/08/200813100642.htm
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Insect diversity boosted by combination of crop diversity and semi-natural habitats
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To enhance the number of beneficial insect species in agricultural land, preserving semi-natural habitats and promoting crop diversity are both needed, according to new research published in the British Ecological Society's
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The study, by researchers in Sweden, the UK, Italy, Germany, Spain and France, found that increasing the diversity of crops in agricultural landscapes increased the diversity of beneficial insects such as pollinators. However, this benefit was only seen in landscapes with high proportions of semi-natural habitats such as forests and grassland.In landscapes with both high crop diversity and semi-natural habitat cover, the researchers observed an increased diversity of ground beetle species as well as pollinators like bees and hoverflies. These insects have the potential to benefit crops through predating pests or pollinating flowering crop plants, both important for crop yields.The same effects were not found for spiders, which surprised the researchers. "We expected pollinators to benefit because they are a highly mobile species, but the difference between ground beetles and spiders is harder to explain since both share similar adaptations to inhabit local crops." said Guillermo Aguilera of the Swedish University of Agricultural Sciences and lead author of the study.Many beneficial insects and invertebrates are in decline, partly due to intensive crop management practices and a loss of semi-natural habitats from agriculture land, meaning the results have important implications. Guillermo Aguilera said: "We show that increasing local insect communities is possible in landscapes with semi-natural habitats by increasing crop diversity. Therefore, reducing the arable land and increasing semi-natural habitats is not always the only way for obtaining benefits from insects."Insects and other invertebrates provide important ecosystem services. "Ground beetles and spiders are predators of species that can become pests. Wild pollinators have one of the most important roles in flowering crops. Both services, pest control and pollination, are important for the final crop yield." explains Guillermo Aguilera.A greater diversity of crops may benefit pollinators through giving them a more varied and continuous food source. Oilseed rape, the most abundant flowering crop in the study area, provides massive resources for pollinators. However, its flowers are only open for a short period of time. Growing other crops that flower throughout the year could help support pollinators.Semi-natural habitats provide nesting sites and additional food for both pollinators and predators. They're likely to be particularly beneficial to mobile species of ground beetles which often colonise crop fields from these habitats.The researchers compiled data from seven previous studies that looked at invertebrate abundances in crop fields. The data spanned 154 crop fields in southern Sweden, an area consisting of arable land and semi-natural habitats, like grassland and woodland, between 2007 and 2017."The ultimate goal was to investigate the effect of crop diversity in the landscape with local communities of invertebrates" said Guillermo Aguilera. "After obtaining the invertebrate information and the coordinates of the fields where they were collected, we analysed the diversity of crops present in the landscape at the time of the sampling as well as the amount of semi-natural habitats such as grasslands."The research focussed on southern Sweden, the most agriculturally important region in the country in terms of crop production. While this gave the researchers a large study area, they acknowledge that it's hard to generalise the results to a more global landscape.Guillermo Aguilera said "It would be interesting to see what happens in other landscapes with a higher crop diversity by default than Sweden. It would also be interesting to look at how invertebrate communities respond to other forms of diversification in agriculture landscapes. For instance, the management of certain crops is something that can vary a lot between countries or regions."
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Agriculture & Food
| 2,020 |
August 11, 2020
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https://www.sciencedaily.com/releases/2020/08/200811120112.htm
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Gluten in wheat: What has changed during 120 years of breeding?
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In recent years, the number of people affected by coeliac disease, wheat allergy or gluten or wheat sensitivity has risen sharply. But why is this the case? Could it be that modern wheat varieties contain more immunoreactive protein than in the past? Results from a study by the Leibniz-Institute for Food Systems Biology at the Technical University of Munich and the Leibniz Institute of Plant Genetics and Crop Plant Research are helping to answer this question.
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Wheat grains contain about 70 percent starch. Their protein content is usually 10 to 12 percent. Gluten accounts for the lion's share of proteins, at around 75 to 80 percent. Gluten is a compound mixture of different protein molecules. These can be roughly divided into two subgroups: "gliadins" and "glutenins."It has long been known that wheat proteins can trigger disorders such as coeliac disease or wheat allergies. Approximately 1 or 0.5 percent of the adult population is affected worldwide. In addition, non-celiac gluten sensitivity (NCGS) is becoming increasingly important in the western world."Many people fear that modern wheat varieties contain more immunoreactive proteins than in the past and that this is the cause of the increased incidence of wheat-related disorders," says Darina Pronin from the Leibniz-Institute for Food Systems Biology, who was significantly involved in the study as part of her doctoral thesis. Where gluten is concerned, the protein group of gliadins in particular is suspected of causing undesired immune reactions, explains the food chemist.But how big are the differences between old and new wheat varieties really? In order to help clarify this, Katharina Scherf and her team at the Leibniz-Institute for Food Systems Biology investigated the protein content of 60 preferred wheat varieties from the period between 1891 and 2010. This was made possible by the Leibniz Institute of Plant Genetics and Crop Plant Research. It has an extensive seed archive. From the archive, the researchers selected five leading wheat varieties for each decade of the 120 years examined. In order to generate comparable samples, they cultivated the different varieties in 2015, 2016 and 2017 under the same geographical and climatic conditions.Analyses by the team of scientists show that, overall, modern wheat varieties contain slightly less protein than old ones. In contrast, the gluten content has remained constant over the last 120 years, although the composition of the gluten has changed slightly. While the proportion of critically viewed gliadins fell by around 18 percent, the proportion of glutenins rose by around 25 percent. In addition, the researchers observed that higher precipitation in the year of the harvest was accompanied by a higher gluten content in the samples."Surprisingly, environmental conditions such as precipitation had an even greater influence on protein composition than changes caused by breeding. In addition, at least on the protein level, we have not found any evidence that the immunoreactive potential of wheat has changed as a result of the cultivation factors," explains Katharina Scherf, who is now continuing her research as a professor at the Karlsruhe Institute of Technology (KIT). However, Scherf also points out that not all protein types contained in wheat have been investigated with regard to their physiological effects. Therefore, there is still a lot of research to be done.
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Agriculture & Food
| 2,020 |
August 10, 2020
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https://www.sciencedaily.com/releases/2020/08/200810160142.htm
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Agtech to the rescue in a pandemic: Adapting plant labs for human testing
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Just as redeploying a fleet of small British fishing boats helped during the Battle of Dunkirk, marshalling the research equipment and expertise of the many agtech labs around the world could help combat pandemics, say the authors of a just-published article in
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Sophisticated agtech labs and equipment used for crop and animal breeding, seed testing, and monitoring of plant and animal diseases could easily be adapted for diagnostic testing and tracing in a human pandemic or epidemic, the article states."If there is anything this current pandemic has shown us, it is that we need to mobilize efforts on a large scale to ramp up diagnostics," said lead author Steven Webb, chief executive officer of the Global Institute for Food Security (GIFS) at the University of Saskatchewan (USask)."We must mobilize 'large ships' to fight pandemics by exploiting and adapting the screening capacity of high-throughput plant breeding laboratories which can rapidly analyze hundreds of thousands of samples."The authors urge a national or international effort to co-ordinate rapid redeployment of digital agriculture infrastructure for pandemic preparedness. This approach would relieve the pressure on limited testing tools in the health sector and speed up the ability to respond with treatment and measures to contain the spread and occurrence of disease."Agtech has the infrastructure and capacity to support this need through its versatile equipment that can be used for very large-scale and automated applications including genetic testing and sequencing, virus detection, protein analysis, and gene expression," Webb said.For instance, automated analysis of new plant varieties could be quickly switched to the automated detection of viral RNA or proteins, as well as detection of neutralizing antibodies, in humans. Selection of the fittest plant cultivars for breeding could be replaced by confirmation of patient diagnose of infectious diseases."As an example, the Omics and Precision Agriculture Laboratory (OPAL) at GIFS combines the digital data analysis of plant genes and traits with the latest precision agriculture technologies, and can provide a complete profile and data analysis of 3,000 plant samples per day," said Webb."Appropriate quality control measures would guide OPAL's switch from plant sample testing and analysis to human sample diagnostics during a pandemic, complying with regulation and using processes personnel are trained to employ."GIFS has already lent equipment to enable expanded testing of COVID-19 blood samples and has donated materials and supplies to the Saskatchewan Health Authority.The article notes that pandemics also affect animals and plants, with severe consequences for human food security, the economy, the environment, and society. For instance, the Great Famine in Ireland caused by the potato blight in the 1800s led to one million deaths and the spread of the blight in Europe claimed another 100,000 lives.The article stresses the need to be able to adapt available agtech infrastructure from 'peacetime' applications to emergency use for diagnostic testing. This requires development of contingency protocols at national and international levels."There needs to be comprehensive quality control, standardizing the process and outcomes of this high-capacity testing of pandemic diagnostic samples," Webb said.As well, there's a need to invest in agricultural technologies that can easily be adapted for medical use during pandemics."We need to be proactive to fight the next one. A proactive approach on all fronts will ensure the world is more prepared with the infrastructure and resources needed to respond to a pandemic," said Webb.Other collaborators on the paper include: Richard Twyman, director of Scientific Management Consultancy TRM Ltd. in the United Kingdom, and Maurice Moloney, founder and management partner of AgritecKnowledge LLC, an international consultancy network for agricultural technologies, also in the United Kingdom.
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Agriculture & Food
| 2,020 |
August 10, 2020
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https://www.sciencedaily.com/releases/2020/08/200810115522.htm
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New research reveals previously hidden features of plant genomes
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An international team led by the Plant Phenotyping and Imaging Research Centre (P2IRC) at the University of Saskatchewan (USask) and researchers at Agriculture and Agri-Food Canada (AAFC) has decoded the full genome for the black mustard plant -- research that will advance breeding of oilseed mustard crops and provide a foundation for improved breeding of wheat, canola and lentils.
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The team, co-led by P2IRC researchers Andrew Sharpe and Isobel Parkin, used a new genome sequencing technology (Nanopore) that results in very long "reads" of DNA and RNA sequences, providing information for crop breeding that was previously not available. The results are published today in "This work provides a new model for building other genome assemblies for crops such as wheat, canola and lentils. Essentially, it's a recipe for generating a genome sequence that works for any crop," said Sharpe, director of P2IRC."We now know that we can get the same quality of genomic data and level of information about genetic variation for these important national and international crops. This means we can make breeding more efficient because we can more easily select genes for specific desired traits."Sharpe said his team is already using this software platform in the Omics and Precision Agriculture Lab (OPAL) at the USask Global Institute for Food Security (GIFS) to sequence larger and more complex crop genomes.Black mustard (Brassica nigra), commonly used in seed form as a cooking spice, is grown on the Indian sub-continent and is closely related to mustard and canola crops grown in Canada. The research provides a clearer, "higher resolution" view of the plant's genes and gives researchers and breeders a more defined view of which genes are responsible for which traits.The resulting gene assembly for black mustard also helps explain how the black mustard genome differs from those of its close crop relatives -- such as cabbage, turnip and canola.The team also uncovered the first direct evidence of functional centromeres, structures on chromosomes essential for plant fertility, and detected other previously hard to identify regions of the genome. This knowledge provides a foundation for improving crop production.Parkin, a USask adjunct professor and P2IRC member, said the use of long-read sequence data has enabled unprecedented access to previously hidden features of plant genomes."This provides not only insights into how crops evolve but enables the identification of novel structural variation -- now known to play an important role in the control of many key agronomic traits," said Parkin, also the lead research scientist with AAFC Saskatoon Research Centre.They also found in the sequence multiple copies of certain genes that express specific traits. This could mean that certain traits, such as fungal resistance, could be expressed more strongly through several genes.Other USask members of the team include GIFS researcher Zahra-Katy Navabi and bioinformatics specialist Chu Shin Koh. Other team members include Sampath Perumal, a post-doctoral fellow with Parkin, as well as others from the University of Ottawa, Thompson River University, the National Research Council, and researchers from the United Kingdom and China."The genome assembly for black mustard that we have developed is a great example of how new Nanopore sequencing technology quickly reveals important genome biology," Sharpe said, noting that this advanced sequencing technology and capability is available to public and private plant breeding organizations through the OPAL at GIFS.
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Agriculture & Food
| 2,020 |
August 10, 2020
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https://www.sciencedaily.com/releases/2020/08/200810113213.htm
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Photosynthetic hacks can boost crop yield, conserve water
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Plants are factories that manufacture yield from light and carbon dioxide -- but parts of this complex process, called photosynthesis, are hindered by a lack of raw materials and machinery. To optimize production, scientists from the University of Essex have resolved two major photosynthetic bottlenecks to boost plant productivity by 27 percent in real-world field conditions, according to a new study published in
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"Like a factory line, plants are only as fast as their slowest machines," said Patricia Lopez-Calcagno, a postdoctoral researcher at Essex, who led this work for the RIPE project. "We have identified some steps that are slower, and what we're doing is enabling these plants to build more machines to speed up these slower steps in photosynthesis."The RIPE project is an international effort led by the University of Illinois to develop more productive crops by improving photosynthesis -- the natural, sunlight-powered process that all plants use to fix carbon dioxide into sugars that fuel growth, development, and ultimately yield. RIPE is supported by the Bill & Melinda Gates Foundation, the U.S. Foundation for Food and Agriculture Research (FFAR), and the U.K. Government's Department for International Development (DFID).A factory's productivity decreases when supplies, transportation channels, and reliable machinery are limited. To find out what limits photosynthesis, researchers have modeled each of the 170 steps of this process to identify how plants could manufacture sugars more efficiently.In this study, the team increased crop growth by 27 percent by resolving two constraints: one in the first part of photosynthesis where plants transform light energy into chemical energy and one in the second part where carbon dioxide is fixed into sugars.Inside two photosystems, sunlight is captured and turned into chemical energy that can be used for other processes in photosynthesis. A transport protein called plastocyanin moves electrons into the photosystem to fuel this process. But plastocyanin has a high affinity for its acceptor protein in the photosystem so it hangs around, failing to shuttle electrons back and forth efficiently.The team addressed this first bottleneck by helping plastocyanin share the load with the addition of cytochrome c6 -- a more efficient transport protein that has a similar function in algae. Plastocyanin requires copper and cytochrome requires iron to function. Depending on the availability of these nutrients, algae can choose between these two transport proteins.At the same time, the team has improved a photosynthetic bottleneck in the Calvin-Benson Cycle -- wherein carbon dioxide is fixed into sugars -- by bulking up the amount of a key enzyme called SBPase, borrowing the additional cellular machinery from another plant species and cyanobacteria.By adding "cellular forklifts" to shuttle electrons into the photosystems and "cellular machinery" for the Calvin Cycle, the team also improved the crop's water-use efficiency, or the ratio of biomass produced to water lost by the plant."In our field trials, we discovered that these plants are using less water to make more biomass," 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. "The mechanism responsible for this additional improvement is not yet clear, but we are continuing to explore this to help us understand why and how this works."These two improvements, when combined, have been shown to increase crop productivity by 52 percent in the greenhouse. More importantly, this study showed up to a 27 percent increase in crop growth in field trials, which is the true test of any crop improvement -- demonstrating that these photosynthetic hacks can boost crop production in real-world growing conditions."This study provides the exciting opportunity to potentially combine three confirmed and independent methods of achieving 20 percent increases in crop productivity," said RIPE Director Stephen Long, Ikenberry Endowed University Chair of Crop Sciences and Plant Biology at the Carl R. Woese Institute for Genomic Biology at Illinois. "Our modeling suggests that stacking this breakthrough with two previous discoveries from the RIPE project could result in additive yield gains totaling as much as 50 to 60 percent in food crops."RIPE's first discovery, published in Next, the team plans to translate these discoveries from tobacco -- a model crop used in this study as a test-bed for genetic improvements because it is easy to engineer, grow, and test -- to staple food crops such as cassava, cowpea, maize, soybean and rice that are needed to feed our growing population this century. 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.Realizing Increased Photosynthetic Efficiency (RIPE) aims to improve photosynthesis to equip farmers worldwide with higher-yielding crops to ensure everyone has enough food to lead a healthy, productive life. This international research project is sponsored by the Bill & Melinda Gates Foundation, the U.S. Foundation for Food and Agriculture Research (FFAR), and the U.K. Government's Department for International Development (DFID).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 |
August 10, 2020
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https://www.sciencedaily.com/releases/2020/08/200810103233.htm
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Land-use change disrupts wild plant pollination on a global scale
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Human changes to the environment have been linked to widespread pollinator declines. New research published in
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Plants provide resources including food and shelter to all other living organisms on earth. Most plants need pollinators to reproduce, which is why mounting research showing widespread pollinator declines is concerning. Despite concerns we are facing a pollination crisis, we do not know which types of plants will be most affected by pollinator declines and under which conditions declines in plant reproductive success are to be expected.Changes in land-use are the leading threat to plants and pollinators. However, different groups of pollinators may have different responses to changes in land-use. For example, some farming practises may increase honeybee abundance on the one hand but reduce the abundance of other pollinators such as wild bees and butterflies on the other hand. Dr Joanne Bennett, who led the research as a postdoctoral researcher at iDiv and MLU and is now working at the University of Canberra, said: "Plants and their pollinators have evolved relationships over millions of years . Humans are now changing these relationships in just a few years."To determine if land use effects pollen limitation, an international team of researchers set out to compile a global dataset that quantified the degree to which pollenation limits plant reproductive success. For this, they analysed thousands of published pollen supplementation experiments -- experiments that estimate the magnitude of pollen limitation by comparing the number of seeds produced by naturally pollinated flowers with flowers receiving hand supplemented pollen. Joanne Bennett said: "If naturally pollinated plants produce less fruits or seeds than plants that have received additional pollen by hand then the reproduction of that plant population is limited -- this is called pollen limitation. In this way, pollen limitation experiments provide an unparalled opportunity to link plant reproductive function to the health of pollination services."It was almost 20 years ago when Prof Dr Tiffany Knight, Alexander von Humboldt professor at MLU and head of the Spatial Interaction Ecology research group at iDiv and UFZ, started to compile the first data sets. Supported by iDiv's synthesis centre sDiv, Knight and Bennett took the project to a new level by forming a group of 16 experts from all over the world to expand the dataset and generate new ideas. The researchers started with 1,000 experiments on 306 plant species from Europe and North America. To date, it includes data from over 2,000 experiments and more than 1,200 plants and has a more global distribution. Tiffany Knight said: "One of the most rewarding components of this research has been the collaboration with the international team, and the inclusion of studies published in languages other than English."Ultimately, this data allowed for a global meta-analysis, which showed that wild plants in intensely used landscapes, such as urban areas, are highly pollen limited. The researchers found that plants that are specialized in their pollination are particularly at risk of pollen limitation, but this varies across the different land-use types and is based on which pollinator taxa they are specialized on. For example, plants specialized on bees were less pollen limited in agriculturally managed lands than those specialized on other pollinator types. This could be because domesticated honey bees support the pollination of wild plants in these lands.The results show conclusively that intensive land use is linked to lower plant reproductive success due to lower pollination success. This suggests that future land-use change will decrease the pollination and reproductive success of plants, and can cause plant communities to become more dominated by species that are generalized in their pollination.
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Agriculture & Food
| 2,020 |
August 7, 2020
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https://www.sciencedaily.com/releases/2020/08/200807153653.htm
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Decline in plant breeding programs could impact food security
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Public plant breeding programs are declining across the United States.
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A team of scientists led by Kate Evans, a Washington State University horticulture professor who leads WSU's pome fruit (apples and pears) breeding program, found that public plant breeding programs are seeing decreases in funding and personnel.The study was published in the journal Evans and her colleagues conducted a survey of 278 plant breeding programs around the country. Public programs are chiefly federal programs, like those run by the U.S. Department of Agriculture, or based at public research universities.In the surveys, respondents estimated a 21.4% decline in full time employee (FTE) time for program leaders over the past five years and an estimated 17.7% decline in FTE time for technical support personnel.The researchers also found that retirement looms for a significant number of plant breeding program leaders. Over a third of the responding programs reported having leaders over the age of 60 and 62% are led by people over 50.This decline is concerning because plant breeding has a direct impact on food security, Evans said."Plant breeding plays a fundamental part of the long-term food security of this country," Evans said. "The tremendous increases in food production over the past century are largely due to plant breeding, and the world's population is only increasing."The focus on food security has received more attention in the last few months, as the COVID-19 pandemic has moved around the world, she said."Plant breeding is a long-term, sustainable way to address concerns over having enough food and keeping our food sources secure," said Evans, who is based at WSU's Tree Fruit Research & Extension Center in Wenatchee.Plant breeding takes on many forms, from breeding disease tolerance, increasing production, introducing new delicious varieties, or improving drought tolerance."It could be a disease, a pest, climate change, any number of things," Evans said. "We do not live in a stable environment, and there are many different ways to deal with that."Plant pathogens, like bacteria, and pests are always adapting, so varieties of crops that were bred to naturally fight off a disease start to lose their defenses. Plant breeding programs help growers stay ahead of those potentially harmful adaptations.Another impact of declining breeding programs is losing those with a local focus."In Washington, for example, our cereal breeding programs are very focused on local production," Evans said. "They breed wheat that grows very well for eastern Washington."Another example is the citrus industry. Citrus greening disease has been devastating to growers, particularly in Florida, when trees produce bitter, green, and misshapen fruit. Plant breeding programs are working hard to develop varieties that naturally repel the pest that causes the problems.One reason that plant breeding programs are declining is expense. It takes many years to develop a new variety of a crop, Evans said. And funding a program for that long requires significant investment."We can't rely on grants because those are often only for a few years," she said. "You can't do anything in plant breeding in three years, it requires long-term sustained funding to get a program going."
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Agriculture & Food
| 2,020 |
August 6, 2020
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https://www.sciencedaily.com/releases/2020/08/200806101804.htm
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Herbicide harming marsupial health and development, research finds
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The health of wallabies and kangaroos is being affected by the herbicide, atrazine, which is used widely in Australia on cereal crops and in forestation to prevent weeds, according to new research.
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Atrazine, which has been banned in the European Union since 2003, may be impacting reproduction in marsupials, the University of Melbourne study found, published today in "Exposures to atrazine is causing major abnormalities in the male reproductive system in many animals, triggering male sterility or even male-to-female sex reversal in frogs," Professor in Genetics Andrew Pask said."With the marsupial's unique mode of reproduction and the young completing their development in the pouch, mothers are unknowingly passing the toxins on in their breast milk, exposing their young to environmental toxins."The study is the first time the impacts of pesticides have been investigated in any marsupial and show that they are able to affect reproductive development.The research found that concentrations of atrazine have been recorded at disturbingly high levels in Victorian rivers and Tasmanian streams immediately after forestry spraying.Kangaroos and wallabies are at high risk because they eat the sprayed crops and drink from contaminated water resources where chemicals such as atrazine accumulate from run off.Atrazine affects a broad range of animals from mammals such as rats to amphibians, reptiles and even fish.With marsupials already experiencing devastating population declines across Australia, and 21 per cent of native mammals currently threatened with extinction, researchers say the potential impacts of environmental toxins are of major concern.Researchers exposed the adult female tammar wallabies to atrazine contaminated water throughout pregnancy, birth and lactation to help establish the extent of harm being caused by the chemical.They then examined the reproductive development of their young by assessing their growth and development.Lead author on the research and PhD student Laura Cook said it is hoped the study will lead to more stringent guidelines around the use of atrazine in Australia."Endocrine-disrupting chemicals, such as atrazine, have the ability to impact development and increase disease susceptibility," she said."With increased habitat destruction, marsupials are being pushed onto farmland, attracted to the food resources and rare permanent water sources where they may be vulnerable to agricultural contaminants, such as pesticides."
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Agriculture & Food
| 2,020 |
August 6, 2020
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https://www.sciencedaily.com/releases/2020/08/200806101802.htm
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Study sheds new light on vein formation in plants
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An international team of researchers including the University of Adelaide, has found plant hormones known as strigolactones suppress the transportation of auxin, the main plant hormone involved in vein formation, so that vein formation occurs slower and with greater focus.
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The research, published in Co-author, Dr Philip Brewer of the University of Adelaide's Waite Research Institute, said scientists know that the interaction between strigolactones and auxin is important for plant responses, but further research in this area is essential to learn how.Vascular plants have veins in leaves, stems and roots that carry water and nutrients to cells, and provide structural support. The hormone auxin flows from new leaves and buds to connect them together and joins them with the stem, and re-joins veins at wound sites, a process call canalisation."Although only recently identified, what we know about strigolactone hormones is that they help plants respond to environmental conditions, such as optimising plant growth to match soil nutrient levels," said Dr Brewer."By observing the interaction of the two hormones in pea and thale cress plants in this study, we found that when applied, strigolactones reduce the transport of auxin and slow vein formation."Strigolactones also supress auxin as it flows through root tips. Specifically, strigolactones limit the way auxin promotes its own transport out of cells," said Dr Brewer.Dr Brewer said plant hormones like auxin and strigolactones have great potential to improve crop productivity."However, understanding how they act is still a major research challenge, and applying hormones in agriculture often results in unwanted side effects," said Dr Brewer."Improved knowledge of how the hormones act allows us to uncover ways to fine-tune hormone responses so that we can realise the benefits and limit the side effects."While more research is needed in this field, this study contributes to fundamental knowledge of plant biology and offers hope of finding new ways to adapt crops to increasingly difficult climate conditions," Dr Brewer said.
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Agriculture & Food
| 2,020 |
August 5, 2020
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https://www.sciencedaily.com/releases/2020/08/200805124052.htm
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Land use changes may increase disease outbreak risks
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Global changes in land use are disrupting the balance of wild animal communities in our environment, and species that carry diseases known to infect humans appear to be benefiting, finds a new UCL-led study.
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The findings, published in The research team, led by the UCL Centre for Biodiversity & Environment Research, studied evidence from 6,801 ecological communities from six continents, and found that animals known to carry pathogens (disease-causing microorganisms) that can infect humans were more common in landscapes intensively used by people.The evidence was sourced from a dataset of 184 studies incorporating close to 7,000 species, 376 of which are known to carry human-shared pathogens.The researchers say we may need to alter how we use land across the world to reduce the risk of future spillovers of infectious diseases.Lead author, PhD candidate Rory Gibb (UCL Centre for Biodiversity & Environment Research) said: "The way humans change landscapes across the world, from natural forest to farmland for example, has consistent impacts on many wild animal species, causing some to decline while some others persist or increase."Our findings show that the animals that remain in more human-dominated environments are those that are more likely to carry infectious diseases that can make people sick."Species that host zoonotic pathogens (which can jump from animals to people) constituted a higher proportion of the animal species found in human-influenced (disturbed) environments compared to the ecological communities in more wild habitats.The same relationship is seen for animals that tend to carry more pathogens of any kind -- whether or not they can affect humans.In comparison, most other wild animal species are found in lower numbers in disturbed environments compared to natural habitats. The researchers say this suggests that similar factors may be influencing both whether a species can tolerate humans and how likely it is to carry potentially zoonotic diseases.Co-lead author Dr David Redding (ZSL Institute of Zoology and UCL Centre for Biodiversity & Environment Research) said: "Other studies have found that outbreaks of emerging zoonotic infectious diseases appear to be increasingly common -- our findings may help to explain that pattern, by clarifying the underlying ecological change processes that are interacting to drive infection risks."Senior author Professor Kate Jones (UCL Centre for Biodiversity & Environment Research and ZSL Institute of Zoology) said: "Global land use change is primarily characterised by the conversion of natural landscapes for agriculture, particularly for food production. Our findings underscore the need to manage agricultural landscapes to protect the health of local people while also ensuring their food security."The researchers say that while there are numerous other factors influencing emergent disease risks, the findings point to strategies that could help mitigate the risk of further infectious disease outbreaks comparable to COVID-19.Professor Jones said: "As agricultural and urban lands are predicted to continue expanding in the coming decades, we should be strengthening disease surveillance and healthcare provision in those areas that are undergoing a lot of land disturbance, as they are increasingly likely to have animals that could be hosting harmful pathogens."Dr Redding added: "Our findings provide a context for thinking about how to manage land use changes more sustainably, in ways that take into account potential risks not only to biodiversity, but also to human health."
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Agriculture & Food
| 2,020 |
August 4, 2020
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https://www.sciencedaily.com/releases/2020/08/200804122223.htm
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Studies shed new light on how biodiversity influences plant decay
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Scientists have provided new insights on the relationship between plant diversity in forests and the diversity of organisms involved in their decay, such as bacteria and fungi.
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Plant litter decomposition is a major ecosystem function, linking plant biomass to carbon stocks in the soil and atmosphere, and releasing nutrients including nitrogen and phosphorus that influence soil biodiversity. Two new independent studies, published today in For the first study, researchers based in China and France analysed the relationship between the diversity of plant litter and decomposition across 65 field studies in forests around the world. Their results show that plant decomposition is faster when litter is composed of more than one species. This was particularly clear in forests with mild temperatures, but were more variable in other forest environments."We also found that plant diversity accelerated the release of nitrogen, but not phosphorus, potentially indicating a shift in ecosystem nutrient limitation caused by a change in biodiversity," explains joint first author Liang Kou, Associate Professor at the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China. "This discovery was again clear for temperate forests, but still needs confirmation for boreal, Mediterranean, subtropical and tropical forests that are currently limited on data.""Our results suggest that biodiversity loss will modify carbon and nutrient cycling in forest ecosystems," adds joint senior author Huimin Wang, Professor at the Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences. "The potential impact of changes in litter diversity on carbon and nutrient cycling warrants particular attention in future studies, which would ideally integrate responses from decomposers for a better understanding of changes in carbon and nutrient cycling and the mechanisms driving them."The second study in "Industrial and agricultural activities can have detrimental effects on decomposer organisms," says first author Léa Beaumelle, a postdoctoral researcher at the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, University of Leipzig, Germany. "They release chemical stressors such as metals and pesticides, as well as nutrients, into soil and water. Chemical stressors and added nutrients modify decomposer communities by affecting their diversity, abundance and metabolism."Previous experiments conducted in simplified conditions have shown that biodiversity loss has detrimental effects on ecosystem processes. But how these results apply to real-world scenarios of change in biodiversity remains unclear. The researchers set out to discover if the responses of plant litter decomposition to chemical stressors and added nutrients can be explained by changes in decomposer diversity across ecosystems.To do this, the team analysed the results of 69 independent studies that reported 660 observations of the effects of chemical stressors or nutrient enrichment on animal and microbial decomposers and on plant litter decomposition. They found that declines in the diversity and abundance of decomposers explained reductions in plant decay rates under the influence of chemical stressors, but not added nutrients. This suggests that human activities decrease decomposer biodiversity, which then leads to significant effects on ecosystem functions."These findings could inform the design of suitable strategies to maintain biodiversity and ecosystem functioning," concludes senior author Nico Eisenhauer, Head of Experimental Interaction Ecology at the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, University of Leipzig. "But they also show that these strategies must take human activities into account and cannot rely solely on improving biodiversity alone."
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Agriculture & Food
| 2,020 |
August 4, 2020
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https://www.sciencedaily.com/releases/2020/08/200804111509.htm
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An easier way to go veggie: Vitamin B12 can be produced during dough fermentation
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Vitamin B12 is an essential micronutrient that is needed for functions such as maintaining the nervous system and forming blood cells. However, B12 is mainly found in food of animal origin. Those who consume only small amounts of animal products or are vegan must therefore take B12 in the form of pills or eat food to which industrially produced B12 has been added.
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"In situ fortification of B12 via fermentation could be a more cost-effective alternative. And as a commonly consumed staple food, grains are excellent vehicles for enrichment with micronutrients," explains Chong Xie from the Faculty of Agriculture and Forestry, University of Helsinki, about the background of his doctoral dissertation.Xie used 11 different grain-based materials and fermented them with Propionibacterium freudenreichii -- the only B12-producing micro-organism accepted for food products.Propionibacterium freudenreichii, the essential microbe in Emmental cheese, produced nutritionally significant amounts of vitamin B12 in most of the fermented grain materials. During the three-day fermentation process, rice bran and buckwheat bran had the highest B12 production. The addition of Lactobacillus brevis was able to dominate indigenous microbes during fermentation and greatly improved microbial safety during the fermentation process.Further information: https://helda.helsinki.fi/bitstream/handle/10138/317682/insitufo.pdf?sequence=1&isAllowed=y
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Agriculture & Food
| 2,020 |
August 3, 2020
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https://www.sciencedaily.com/releases/2020/08/200803140042.htm
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Strategy for sustainable aquaculture, the world's fastest growing food sector
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As the population grows, and the global standard of living improves, humanity's appetite for seafood is increasing. In 2020 seafood consumption reached an all-time high, with an average of 20kg consumed annually by every person on the planet.
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Up to now most of this was caught in the world's freshwaters and oceans. But things are changing, and today half of all seafood consumed comes from farmed sources, called aquaculture. The sector is expected to double by 2050 to supply the increasing global demand.UC Santa Barbara Assistant Professor Halley E. Froehlich has contributed to an evaluation of the complex interactions between human, environmental and animal health parameters of this budding industry, a view scientists call the One Health framework. The study, published in the journal "Aquaculture is now being more widely recognized as an important part of our global food system," said Froehlich, a faculty member in the departments of environmental studies and of ecology, evolution, and marine biology. "And it will continue to grow. So the question is, how do we plot that course in a more sustainable way?"Aquaculture has played a major role in lifting millions of people out of poverty in many low and middle-income nations, but it faces a range of sustainability challenges. These include environmental degradation, overuse of antibiotics, release of disease agents and the requirement of wild-caught fish meal and fish oil to produce feed. Parts of the industry also engage in poor labor practices and gender inequality.Negative societal impressions created by such examples mask aquaculture's potentially significant benefits. Farming cold-blooded animals is very efficient from a nutrient perspective. Many species, such as oysters, don't even require feeding. In addition, aquaculture can operate on a smaller footprint than many other forms of food production.The new paper uses the One Health framework to lay out a set of metrics to include in national aquaculture strategies across the globe to improve sustainability as the industry expands. These include concepts like access to nutritious food and quality employment, the health of wild fish stocks and ecosystems and maintaining a small environmental footprint and resilience to climate change.Communication, cooperation and coordination will be critical to the sustainable development of aquaculture as the sector grows. "If you don't have that knowledge transfer -- for instance, from scientists to policy-makers or farmers to scientists -- these types of framework structures won't go anywhere," Froehlich said.With that in mind, the authors collaborated widely on this report. "The paper results from extensive interaction between a wide range of academic experts in aquaculture, health, environmental and social sciences, economists, industry stakeholders and policy groups," said senior co-author Charles Tyler from the University of Exeter.The paper presents a strategy for developing aquiculture as well as the benchmarks to which we will measure its sustainability and success. "This is an important paper," said lead author, Grant Stentiford of the Centre for Environment, Fisheries and Aquaculture Science, "acknowledging that aquaculture is set to deliver most of our seafood by 2050, but also that sustainability must be designed-in at every level."The One Health approach offers a tool for governments to consider when designing policies. "I hope it will become a blueprint for how government and industry interact on these issues in the future," Stentiford added. "Most importantly, it considers aquaculture's evolution from a subject studied by specialists to an important food sector -- requiring now a much broader interaction with policy and society than arguably has occurred in the past."Some of these principles are already being applied in the European Union and in Norway, according to Froehlich, who has begun shifting her focus toward the industry in the United States, especially California. She is currently in the middle of a Sea Grant project collecting the most comprehensive dataset of marine aquaculture information from across all coastal states in the U.S. This includes practices, policies, and the hidden interactions with fisheries that influence how aquaculture is conducted in each state."Aquaculture is everywhere and nowhere at the same time," Froehlich said. "People don't realize how integrated it is into so many facets of marine ecology, conservation biology, and fisheries."
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Agriculture & Food
| 2,020 |
August 3, 2020
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https://www.sciencedaily.com/releases/2020/08/200803105233.htm
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Exploring the sustainability of the Indian sugar industry
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Generations of political support for sugar cultivation have helped India become the second-largest producer of sugar worldwide. Now, the country's commitment to renewable energy could create additional benefits, like conserving natural resources and providing better nutrition to the poor.
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Stanford researchers conducted the first comprehensive analysis of India's sugar industry and its impact on water, food and energy resources through the lens of its political economy -- that is, how entrenched political interests in sugar production threaten food, water and energy security over time. The results show that a national biofuel policy encouraging production of ethanol made directly from sugarcane juice may make India's water and energy resources more sustainable. Using sugarcane juice instead of molasses would also free up land and irrigation water for growing nutrient-rich foods. The research was published July 24 in "There are spillover effects between sectors, unintended consequences," said co-author Rosamond Naylor, a food security expert and the William Wrigley Professor in Stanford's School of Earth, Energy & Environmental Sciences (Stanford Earth). "It's very instructive to think about the connection between food, water and energy because the solution may not be in the sector you're focusing on."Somewhat analogous to the corn industry in the U.S., which has shifted about 40 percent of its output to ethanol production in recent years, policymakers in India -- many of whom benefit financially from the sugar industry -- are currently exploring how to use sugarcane to increase energy independence and shift toward renewable energy use.The Indian government has set a goal to increase the ethanol-to-gasoline blending rate from its current rate of about 6 percent to 20 percent by 2030 and introduced several policies to promote production of ethanol from sugarcane. The increased blending rate is a "desirable goal for improved energy security," the researchers write. However, its effects on human health and the environment will largely depend on which sugar product ends up being the main feedstock: juice extracted from crushed sugarcane, or molasses, a by-product from sugar processing.India's national policy on biofuels only recently began allowing use of sugarcane juice in ethanol production, in addition to molasses."If the energy industry continues to use molasses as the bioethanol feedstock to meet its target, it would require additional water and land resources and result in the production of extra sugar," said co-author Anjuli Jain Figueroa, a postdoctoral researcher in Earth system science. "In contrast, if the industry used the sugarcane juice to produce ethanol, the target could be met without requiring additional water and land beyond current levels."Using sugarcane juice to create ethanol could also help alleviate government spending to subsidize sugar and sell it below cost in its public distribution system.The public distribution system of sugar in India dates to the 1950s, when frequent famines plagued the country. Back then, sugar helped to meet basic calorie requirements. But today -- with micronutrient deficiency leading to illness, disabilities and even death -- the Indian government is more concerned with nutrition."In India right now, even poor populations have met their basic calorie needs," said Naylor, who is also a senior fellow at the Stanford Woods Institute for the Environment. "They have been able to buy sugar at subsidized prices, but meanwhile they don't have access to adequate protein and micronutrients for cognitive growth and for physical well-being."Sugarcane cultivation in India has expanded in part because of policies that incentivize production, including a minimum price, guaranteed sales of sugarcane and public distribution of sugar. These regulations have become entrenched over many generations, making the crop highly profitable to the 6 million farmers in the country, but the empty-calorie crop reduces the amount of resources available for micronutrient-rich foods."Using scarce natural resources to produce a crop that doesn't fulfill nutritional needs for the second most populated country in the world can place pressure on the global food system if more and more food imports are required to meet the rising demand in India," Naylor said.The researchers focused their analysis on Maharashtra in western India, one of the country's largest sugarcane-producing states. Sugarcane cultivation in Maharashtra has increased sevenfold in the past 50 years to become the dominant user of irrigation water. The study found that in 2010-11, sugarcane occupied only 4 percent of Maharashtra's total cropped areas but used 61 percent of the state's irrigation water. Meanwhile, irrigation for other nutritious food crops remained lower than the national averages."Irrigation of sugarcane in our study region is about four times that of all other crops and has doubled from 2000 to 2010. This resulted in about a 50 percent reduction of river flow over that period," said co-author Steven Gorelick, the Cyrus Fisher Tolman Professor at Stanford Earth. "Given that this region is susceptible to significant drought, future water management is likely to be quite challenging."As part of continued efforts to examine the Indian sugar industry and its impacts, lead author Ju Young Lee, a PhD student in Earth system science, also developed satellite imagery analyses to identify sugarcane from space."Despite the importance of sugarcane in the water, food and energy sectors in India, there are no reliable sugarcane maps for recent years and in time series," Lee said. "Using remote sensing data, I am developing current time-series sugarcane maps in Maharashtra -- an important step forward."The agricultural area of Maharashtra is considered drought-ridden, and yet in September 2019, the region experienced major floods that killed 21 people and caused 28,000 residents of Pune city to evacuate.While the researchers started the FUSE project in Maharashtra with an explicit focus on drought management, their objectives expanded to include flooding after witnessing the devastation of Pune during their research period, presenting "a far more difficult water management problem," according to co-author Steven Gorelick."Climate projections over the next 40 to 80 years suggest maybe a 10 percent increase in rainfall, but much greater variability -- and that variability is what worries me the most, in terms of future management of both floods and droughts," Gorelick said.
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Agriculture & Food
| 2,020 |
July 29, 2020
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https://www.sciencedaily.com/releases/2020/07/200729114840.htm
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Studying interactions between ground-nesting bees and soils
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Many living creatures live in soil. Though their sizes range from microscopic soil microbes to larger animals like gopher turtles, they all call soil their "home." Included in these ground-dwelling species are bees -- vital in the pollination cycle of about 90% of plant life.
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Rebecca Lybrand and her team at Oregon State University are studying the interaction between the bees and soil in agricultural settings.According to the recently-published paper, bees contribute $15 billion to crop value annually. They pollinate about three-quarters of the fruits, vegetables, and nuts within the United States alone. Declines in honeybee colonies are a critical threat to agriculture and the global food supply."Growers who are interested in attracting alternative pollinators, such as wild bees, face a major challenge," says Lybrand. "There are not many studies about what habitats are best for these wild bees."Pollinators are widely affected by human land use. Creating buildings, parking lots and other "anthropogenic changes" disrupt the natural habitats of animals and plants. Agricultural disturbance also affects bee communities. Interestingly, above-ground bee species are nine times more affected by agricultural intensification than ground-dwelling species.In some cases, growers have been able to build "bee beds" in their farm setting. In the 1950s, they started to design moist, salty soil areas to attract ground-nesting bees that helped increase alfalfa yields in Washington state.Lybrand's study looked at physical and chemical properties of soils collected from active bee and sand nest wasp sites in the Willamette Valley of western Oregon. They compared soil properties among seven farm sites to identify similarities and differences.The Willamette Valley has wet winters with warm, hot summers. The team first found agricultural sites that contained ground-nesting bees. They collaborated with farmers who observed ground-nesting bee activity around their fields.The nests are only identified by rather small holes (only 3-5mm). The team only collected data if they observed bees entering the nest. Nests and holes can remain even after the bees leave. At the study site, they specified the type of bee to the family level (i.e. "bee" versus "genus" and "species." ) But they also collected some bees to bring back to the lab for further identification.The data the team collected in the field included soil temperature, pH, and soil texture. They also collected soil samples to bring back to the lab for analysis.Findings from the study included that active nesting sites were present in locations with little to no rock cover and low vegetation. Nesting sites were found in areas with low organic matter coverage. The slope of the land didn't seem to have any influence, nor did a north/south-facing aspect."One of our observations confirmed that active emergence holes remained open throughout the year," says Lybrand. "They didn't swell shut during the wetter, cooler seasons -- despite having clay in the soils that might cause shrinking and swelling."An interesting finding from the research is that the team found lipids in the soil nest linings. The lipids may provide a type of waterproofing for the nests and their inhabitants."Because the large majority of wild bee species nest in the soil, studies about how to best attract them to farms are important," says Lybrand. "Soil scientists and entomologists can partner with growers to identify soil habitats that support and attract more of these pollinators to agricultural lands. Improving our understanding of the connections between agriculture and the soils that bees, crops, and living organisms rely on to survive is important. Our research also provided a framework for studying ground-nesting organisms -- an area of soil science that is underrepresented."Looking to the future, Lybrand says, "future research should also integrate methods that identify bees and/or wasps to the species level. That would allow for interpretations of the results from an ecological point of view. Another question to follow up on could be the nature and purpose of the lipids found in the soil nest linings, to confirm their actual role."
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Agriculture & Food
| 2,020 |
July 28, 2020
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https://www.sciencedaily.com/releases/2020/07/200728201558.htm
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Decline of bees, other pollinators threatens US crop yields
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Crop yields for apples, cherries and blueberries across the United States are being reduced by a lack of pollinators, according to Rutgers-led research, the most comprehensive study of its kind to date.
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Most of the world's crops depend on honeybees and wild bees for pollination, so declines in both managed and wild bee populations raise concerns about food security, notes the study in the journal Proceedings of the Royal Society B: Biological Sciences."We found that many crops are pollination-limited, meaning crop production would be higher if crop flowers received more pollination. We also found that honey bees and wild bees provided similar amounts of pollination overall," said senior author Rachael Winfree, a professor in the Department of Ecology, Evolution, and Natural Resources in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick. "Managing habitat for native bee species and/or stocking more honey bees would boost pollination levels and could increase crop production."Pollination by wild and managed insects is critical for most crops, including those providing essential micronutrients, and is essential for food security, the study notes. In the U.S., the production of crops that depend on pollinators generates more than $50 billion a year. According to recent evidence, European honey bees (Apis mellifera) and some native wild bee species are in decline.At 131 farms across the United States and in British Columbia, Canada, scientists collected data on insect pollination of crop flowers and yield for apples, highbush blueberries, sweet cherries, tart cherries, almond, watermelon and pumpkin. Of those, apples, sweet cherries, tart cherries and blueberries showed evidence of being limited by pollination, indicating that yields are currently lower than they would be with full pollination. Wild bees and honey bees provided similar amounts of pollination for most crops.The annual production value of wild pollinators for all seven crops was an estimated $1.5 billion-plus in the U.S. The value of wild bee pollination for all pollinator-dependent crops would be much greater."Our findings show that pollinator declines could translate directly into decreased yields for most of the crops studied," the study says. The findings suggest that adopting practices that conserve or augment wild bees, such as enhancing wildflowers and using managed pollinators other than honey bees, is likely to boost yields. Increasing investment in honey bee colonies is another alternative.James Reilly, a research associate in Winfree's lab, led the study, which used data collected by researchers at many universities and was part of The Integrated Crop Pollination Project funded by the USDA-NIFA Specialty Crop Research Initiative.
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Agriculture & Food
| 2,020 |
July 28, 2020
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https://www.sciencedaily.com/releases/2020/07/200728130821.htm
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Research could save years of breeding for new Miscanthus hybrids
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As climate change becomes increasingly difficult to ignore, scientists are working to diversify and improve alternatives to fossil-fuel-based energy. Renewable bioenergy crops, such as the perennial grass Miscanthus, show promise for cellulosic ethanol production and other uses, but current hybrids are limited by environmental conditions and susceptibility to pests and diseases.
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Breeders have been working to develop new Miscanthus hybrids for years, but the clonal crop's sterility, complex genome, and long time to maturity make conventional breeding difficult. In a new study, University of Illinois researchers mine the crop's vast genomic potential in an effort to speed up the breeding process and maximize its most desirable traits."The method we're using, genomic selection, can shorten the time it takes to breed a new hybrid by at least half," says Marcus Olatoye, lead author on the study and postdoctoral researcher in the Department of Crop Sciences at Illinois. "That's the overall goal."In conventional breeding, one typical approach is for researchers to grow individuals from a diverse set of populations and select those with the best traits for mating. But, for Miscanthus, those traits don't show up until plants are 2-3 years old. Even after plants from this first generation are mated, it takes the offspring another 2-3 years to reveal whether the desired traits were faithfully passed on.In genomic selection, scientists take genetic samples from seeds or seedlings in a target population. This is the group of plants that would ordinarily have to be grown to maturity before experimental crosses are made. Meanwhile, the researchers compile both genetic and phenotypic data from related populations, known as reference or training sets, into a statistical model. Cross-referencing genetic data from the target population with data in the model allows the researchers to predict the phenotypic outcome of hypothetical crosses within the target population.This allows breeders to cut to the chase, pursuing only the most promising crosses with further field testing."Ideally, this process could allow breeders to make selections based on predicted phenotypic values before plants are even planted," says Alex Lipka, associate professor of biometry in the Department of Crop Sciences and co-author on the study. "Specifically, we want to make selections to optimize winter hardiness, biomass, disease tolerance, and flowering time in Miscanthus, all of which limit the crop's performance in various regions of North America."Although it's not a simple process in the best of times, genomic selection in Miscanthus is orders of magnitude more challenging than in other crops. The hybrid of interest, Miscanthus × giganteus, is the product of two separate species, Miscanthus sinensis and Miscanthus sacchariflorus, each of which have different numbers of chromosomes and contain a great deal of variation within and across natural populations."As far as we know, no one has tried to train genomic selection models from two separate species before. We decided to go totally nuts here," Lipka says. "Unfortunately, we found the two parent species do not do a very good job of predicting biofuel traits in Miscanthus × giganteus."The problem was twofold. First, the statistical model simply revealed too much genetic variation among parental subpopulations to capture the impact of genes controlling biofuel traits. This meant the parental populations chosen for the reference set were too diverse to reliably predict traits in the hybrid Miscanthus × giganteus. And second, the genes controlling a particular trait -- like those related to biofuel potential -- seemed to be different in the two parent species.In other words, the genomes contributing to Miscanthus × giganteus are highly complex, explaining why the statistical approach had a hard time predicting traits in offspring from the two parents.Still, the research team kept trying. In a simulation study, Olatoye created 50 Miscanthus × giganteus families, each derived from parents randomly selected from both species. He selectively dialed genetic contributions of each parent up and down, and these contributions formed the genetic basis of simulated phenotypes. The intention of the study was to provide a better view of which individuals and populations might be most valuable for crosses in real life."The results suggest the best strategy for utilizing diversity in the parents is to fit genomic selection models within each parental species separately, and then add the predicted Miscanthus × giganteus trait values from the two models separately," Olatoye says.Although the researchers have more work to do, the simulation study proved genomic selection can work for Miscanthus × giganteus. The next step is further refining which populations are used to train the statistical model and evaluating crosses in the field.
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Agriculture & Food
| 2,020 |
July 28, 2020
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https://www.sciencedaily.com/releases/2020/07/200728121218.htm
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Combating a pandemic is 500 times more expensive than preventing one, research suggests
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According to new research, the failure to protect tropical rain forests has cost trillions of dollars stemming from the coronavirus pandemic, which has wreaked economic havoc and caused historic levels of unemployment in the United States and around the world.
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For decades, scientists and environmental activists have been trying to draw the world's attention to the many harms caused by the rapid destruction of tropical forests. One of these harms is the emergence of new diseases that are transmitted between wild animals and humans, either through direct contact or through contact with livestock that is then eaten by humans. The SARS-CoV-2 virus -- which has so far infected more than 15 million people worldwide -- appears to have been transmitted from bats to humans in China."Much of this traces back to our indifference about what has been occurring at the edges of tropical forests," says Les Kaufman, a Boston University professor of biology.He recently brought together 18 experts from Princeton University, Duke University, Conservation International, and other institutions, to better understand the economic costs of reducing transmission of viruses like the novel coronavirus. Looking at existing research, they made a startling realization.They discovered that significantly reducing transmission of new diseases from tropical forests would cost, globally, between $22.2 and $30.7 billion each year. In stark contrast, they found that the COVID-19 pandemic will likely end up costing between $8.1 and $15.8 trillion globally -- roughly 500 times as costly as what it would take to invest in proposed preventive measures. To estimate the total financial cost of COVID-19, researchers included both the lost gross domestic product and the economic and workforce cost of hundreds of thousands of deaths worldwide. They published their findings in a policy brief in The researchers say disease transmission from wild animals to humans occurs frequently near the edges of tropical forests, where human incursions increase the likelihood of contact with animals. These incursions take the form of logging, cattle ranching, and other livestock businesses, and the exotic animal trade, among others. Tropical forests are often cut down in a patchwork or checkerboard pattern, increasing the amount of land that lies at the edges of the forest and thus increasing the risk for disease transmission between species that would normally live in different ecosystems.To reduce disease transmission, Kaufman and his collaborators propose expanding wildlife trade monitoring programs, investing in efforts to end the wild meat trade in China, investing in policies to reduce deforestation by 40 percent, and fighting the transmission of disease from wild animals to livestock.In China alone, wildlife farming (a government-monitored effort to sustainably hunt wild animals without overhunting them) is an approximately $20 billion industry, employing 15 million people, say Kaufman and his peers. In many China communities, the purchase of wildlife and bushmeat -- meat from wildlife species -- is a status symbol.The researchers also propose to increase funding for creating an open source library of the unique genetic signatures of known viruses, which could help quickly pinpoint the source of emerging diseases and catch them more quickly, before they can spread.Every year, two new viruses are estimated to transfer from animals to humans, the researchers say. Historically, these have included HIV, MERS, SARS-CoV-1, H1N1, and most recently, the SARS-CoV-2 virus that causes COVID-19. Kaufman and his colleagues hope that their report will spur governments around the world, including the US government, to help fund these preventive measures.There are some signs of hope, they say, including the February announcement by the Standing Committee of the National People's Congress that wildlife consumption for food or related trade would be banned in China."The pandemic gives an incentive to do something addressing concerns that are immediate and threatening to individuals, and that's what moves people," says Kaufman. "There are many people who might object to the United States fronting money, but it's in our own best interest. Nothing seems more prudent than to give ourselves time to deal with this pandemic before the next one comes."
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Agriculture & Food
| 2,020 |
July 28, 2020
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https://www.sciencedaily.com/releases/2020/07/200728113528.htm
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Scientists unlock genetic secrets of wine growers' worst enemy
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Following a decade-long effort, scientists have mapped out the genome of an aphid-like pest capable of decimating vineyards. In so doing, they have discovered how it spreads -- and potentially how to stop it.
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The research team's work on the genome was published this past week in a "In effect, phylloxera creates its own refrigerator on the plant that it can feed from whenever it wants," said Paul Nabity, an assistant professor of plant-insect ecology at UC Riverside. In addition to feeding the insects, these structures also protect them from attack by other parasites.A heavy phylloxera infestation, as occurred in the Pacific Northwest last year, could cause grapevines to lose their leaves. If the infestation reaches the roots, the plants could die.The tumor-like structures, known as galls, disrupt the vine's ability to move nutrients and feed itself. They also create wounds in roots that make grapevines more susceptible to fungi and other pathogens, ultimately killing the vines.Claude Rispe from the French National Institute for Agriculture, Food, and Environment led the research team, while Nabity helped identify how phylloxera secrete molecules that can change the immune system of grapevines."These molecules alter the plant's defense systems and make it so that the plant doesn't know it's being attacked," Nabity said.When phylloxera was accidentally introduced to Europe in the 1860s, it nearly brought French viticulture to an end, causing vines to weaken and die. French and American scientists collaborated on a solution that is still used today.Native North American grapevines co-evolved with phylloxera and are now resistant to it. However, most of the grapes we eat and drink are European varieties. As a result, growers have to graft North American roots onto their European grapevines to give them tolerance to this insect.Though phylloxera are considered negative, not all of their effects on plants are necessarily bad. When they feed on plants and start creating gall structures, they change the cells in the leaf surface. Protective cells on the leaves become tiny pores called stomata, which allow movement of gases in and out of the cells."We think this is a means to reduce the negative impact on its host," Nabity said. "Stomata can create carbon gains for plants that can offset how much the insects are taking from it."Now that the genes involved in the attack on non-native grapes have been identified, it may be possible to engineer phylloxera-resistant grapevines."Growers currently have to graft roots to make their plants viable," Nabity said. "A lot of money and effort could be saved with pest-resistant rootstocks."
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Agriculture & Food
| 2,020 |
July 28, 2020
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https://www.sciencedaily.com/releases/2020/07/200728113520.htm
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Soil animals are getting smaller with climate change
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The biomass of small animals that decompose plants in the soil and thus maintain its fertility is declining both as a result of climate change and over-intensive cultivation. To their surprise, however, scientists have discovered that this effect occurs in two different ways: while the changing climate reduces the body size of the organisms, cultivation reduces their frequency. Even by farming organically, it is not possible to counteract all negative consequences of climate change.
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Today, life in the soil must contend with several problems at once. The biomass of small animals that decompose plants in the soil and thus maintain its fertility is declining both as a result of climate change and over-intensive cultivation. To their surprise, however, scientists from the Helmholtz Centre for Environmental Research (UFZ) and the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig have discovered that this effect occurs in two different ways: while the changing climate reduces the body size of the organisms, cultivation reduces their frequency. Even by farming organically, it is not possible to counteract all negative consequences of climate change, the researchers warn in the trade journal Largely unnoticed and in secret, an army of tiny service providers works below our feet. Countless small insects, arachnids and other soil dwellers are indefatigably busy decomposing dead plants and other organic material, and recycling the nutrients they contain. However, experts have long feared that these organisms, which are so important for soil fertility and the functioning of ecosystems, are increasingly coming under stress.On the one hand, they are confronted with the consequences of climate change, which challenges them with high temperatures and unusual precipitation conditions with more frequent droughts. On the other hand, they also suffer from over-intensive land use. If, for example, a meadow is turned into a field, soil animals find fewer niches and food sources there. Intensive ploughing, mowing or grazing, as well as the use of pesticides and large amounts of fertilizer also have a negative effect. But what happens when soil life is faced with both challenges at the same time? "Until now, we knew almost nothing about this," says Dr Martin Schädler from the UFZ. But he and his colleagues at the UFZ and iDiv have very good opportunities to pursue such complex questions. The ecologist coordinates the "Global Change Experimental Facility" (GCEF) in Bad Lauchstädt near Halle. There, researchers can simulate the climate of the future on arable and grassland plots used with varying degrees of intensity. In large steel constructions reminiscent of greenhouses without a roof or walls, they recreate a scenario that could be typical for the region between 2070 and 2100: it is about 0.6 degrees warmer than today, in spring and autumn there is ten percent more precipitation and summers are about 20 percent drier. A team led by Martin Schädler and doctoral student Rui Yin has now investigated how these conditions affect mites and springtails. Both groups have many decomposers in their ranks, which play an important role in the nutrient cycles in the soil.The results show that these soil animals are likely to dwindle even further due to climate change. "It is likely that not only smaller species will prevail, but also smaller individuals within the same species," says Martin Schädler. In any case, the examined specimens on the areas with higher temperatures and changed precipitation were on average about ten percent smaller than on the comparable areas with today's climate. Biologists have so far been familiar with such connections between body size and climate primarily in larger animals. For example, bear species in warm regions of the Earth are significantly smaller than the polar bear found in the Arctic. This is due to the fact that a small body has a comparatively large surface area over which it can release heat -- which is an advantage in the tropics, but easily leads to cooling in polar regions. In poikilothermal animals such as insects, high temperatures also stimulate metabolism and developmental speed. "This creates new generations faster, but they remain smaller," explains Martin Schädler. If the mites and springtails from the plots with an altered climate are weighed, the total weight is therefore lower in comparison with those from the unaffected areas. But this is not good news. After all, these animals' decomposition performance also depends on this biomass. Less total weight therefore also means that nutrient recycling is slowed down. According to the experiment, over-intensive land use can also trigger a very similar effect. This is because the biomass in the soil also decreases as a result. "Interestingly, however, there is another process behind this," says Martin Schädler, summarising the most important result of the study. "Unlike the climate, use does not reduce the size of the animals, but their density." For example, around 47 percent fewer mites and springtails lived on GCEF plots cultivated conventionally compared with plots extensively used as meadows."The fascinating and sobering thing about it is that the effects of climate and use hardly influence each other," says the ecologist. Until now, many experts had hoped that eco-friendly agriculture could offer some kind of insurance against the negative consequences of climate change. After all, organic farming generally leads to a more diverse community in fields and grassland. However, it is thought that this makes such ecosystems less susceptible to climatic disturbances than conventionally used areas.Yet when it comes to maintaining the performance of soil animals, this strategy does not seem to work: changes in temperature and precipitation reduce their biomass regardless of cultivation. "So not everything that threatens to break down as a result of warming can be saved by environmentally friendly land use," says Martin Schädler in summary. In order to mitigate the consequences of climate change, it is therefore necessary to tackle greenhouse gases directly -- and as quickly as possible. "We can't assume that we'll come up with anything else."
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Agriculture & Food
| 2,020 |
July 24, 2020
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https://www.sciencedaily.com/releases/2020/07/200724191441.htm
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Plant-based diets shown to lower blood pressure even with limited meat and dairy
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Consuming a plant-based diet can lower blood pressure even if small amounts of meat and dairy are consumed too, according to new research from the University of Warwick.
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Published online by a team from Warwick Medical School in the Plant-based diets support high consumption of fruits, vegetables, whole grains, legumes, nuts and seeds, limiting the consumption of most or all animal products (mainly meat and diary). High blood pressure is the leading risk factor globally for heart attacks, strokes and other cardiovascular diseases. A reduction in blood pressure has important health benefits both for individuals and for populations. Unhealthy diets are responsible for more deaths and disabilities globally than tobacco use, high alcohol intake, drug use and unsafe sex put together. An increased consumption of whole grains, vegetables, nuts and seeds, and fruit, as achieved in plant-based diets, could avert up to 1.7, 1.8, 2.5 and 4.9 million deaths globally respectively every year according to previous research.Vegetarian and vegan diets with complete absence of animal products are already known to lower blood pressure compared to omnivorous diets. Their feasibility and sustainability are, however, limited. Until now, it has not been known whether a complete absence of animal products is necessary in plant-based dietary patterns to achieve a significant beneficial effect on blood pressure.Lead author Joshua Gibbs, a student in the University of Warwick School of Life Sciences, said: "We reviewed 41 studies involving 8,416 participants, in which the effects of seven different plant-based diets (including DASH, Mediterranean, Vegetarian, Vegan, Nordic, high fibre and high fruit and vegetables) on blood pressure were studied in controlled clinical trials. A systematic review and meta-analysis of these studies showed that most of these diets lowered blood pressure. The DASH diet had the largest effect reducing blood pressure by 5.53/3.79 mmHg compared to a control diet, and by 8.74/6.05 mmHg when compared to a 'usual' diet."A blood pressure reduction of the scale caused by a higher consumption of plant-based diets, even with limited animal products would result in a 14% reduction in strokes, a 9% reduction in heart attacks and a 7% reduction in overall mortality."This is a significant finding as it highlights that complete eradication of animal products is not necessary to produce reductions and improvements in blood pressure. Essentially, any shift towards a plant-based diet is a good one."Senior author Professor Francesco Cappuccio of Warwick Medical School said: "The adoption of plant-based dietary patterns would also play a role in global food sustainability and security. They would contribute to a reduction in land use due to human activities, to global water conservation and to a significant reduction in global greenhouse gas emission."The study shows the efficacy of a plant-based diet on blood pressure. However, the translation of this knowledge into real benefits to people, i.e. its effectiveness, depends on a variety of factors related to both individual choices and to governments' policy decisions. For example, for an individual, the ability to adopt a plant-based diet would be influenced by socio-economic factors (costs, availability, access), perceived benefits and difficulties, resistance to change, age, health status, low adherence due to palatability and acceptance."To overcome these barriers, we ought to formulate strategies to influence beliefs about plant-based diets, plant food availability and costs, multisectoral actions to foster policy changes focusing on environmental sustainability of food production, science gathering and health consequences."Details of the seven plant-based diets examined (Table 1 in the research paper):Plant-based diet & principal components:
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Agriculture & Food
| 2,020 |
July 24, 2020
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https://www.sciencedaily.com/releases/2020/07/200724104144.htm
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Livestock expansion is a factor in global pandemics
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The growth of global livestock farming is a threat to our biodiversity and also increases the health risks to both humans and domesticated animals. The patterns that link them are at the heart of a study published in
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Research has shown a global increase in the emergence of infectious diseases and epidemics, an accelerated loss of biodiversity and a marked increase in the breeding of domesticated animals. This subject was brought back to the fore by the COVID-19 outbreak and a new study in parasite ecology is providing some initial answers to the ongoing question of whether these events are connected. Its goal was to trace the global patterns of biodiversity and infectious diseases both spatially and temporally.To achieve this, the researcher cross referenced various open databasesThe study brings up the question of the place of farmed animals and their increase across the world, which varies according to factors such as human demographics and diet. In order to lower the health risk and protect biodiversity we need to take into account the cultural value of animals to reflect on the place of both wild and domesticated species. Future studies will examine the role played by livestock in pandemics by looking at, on the one hand, the cultivation of vegetable protein needed for feed, which contributes to reduce the space for wild animals, and on the other, on the role of livestock as an epidemiological bridge between wildlife and humans facilitating the transmission of pathogens.1. The Global Infectious Diseases and Epidemiology Online Network (GIDEON) was used for data on human epidemics, the World Organisation for Animal Health was used for data on animal epidemics, the Food and Agricultural Organisation of the United Nations was used for data on livestock production, and the International Union for Conservation of Nature was used for data on biodiversity and endangered species.
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Agriculture & Food
| 2,020 |
July 23, 2020
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https://www.sciencedaily.com/releases/2020/07/200723172212.htm
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Bee disease spreading via flowers
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One in 11 flowers carries disease-causing parasites known to contribute to bee declines, according to a Cornell University study that identifies how flowers act as hubs for transmitting diseases to bees and other pollinators.
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The study, published July 20 in The study was conducted in field sites in upstate New York, where the researchers screened 2,624 flowers from 89 species and 2,672 bees from 110 species for bee parasites through an entire growing season. They used molecular data to identify five common protozoan (free-living, single-celled) and fungal parasites."We know very little about transmission of these diseases," said senior author Scott McArt, assistant professor of entomology in the College of Agriculture and Life Sciences. "Our study shows that transmission can likely occur on a lot of different flowers, and the amount of disease in a community is shaped by both the floral community and the bee community."The researchers found three main factors -- flower abundance, numbers of social bees and bee diversity -- played roles in disease transmission.As the season progresses, the number of flowers goes up. For example, in the fall, flower-laden goldenrod dominates many New York fields. At the same time, the proportion of flowers with parasites goes down, lowering the risk that a bee will pick up a parasite when it visits a flower."That has really important conservation implications, because if you want to limit disease spread, just plant a lot of flowers," said McArt, adding that planting flowers also provides food for pollinators. "It's a win-win: If we plant flowers and create a lot of forage, we can also dilute disease."The study revealed that social bees, such as honeybees and bumblebees, were more likely to be infected with parasites than solitary bee species. The researchers found that later in the season, the number of social bees increases, while bee diversity overall decreases.And as a general rule, diversity of species lowers the spread of disease."Both bee diversity and fewer of the social bees make it less likely for bees [overall] to be infected. That's another win for conservation: if we promote bee diversity, there will be less disease," McArt said. High numbers of infections in the social species may also spill over to infect other species, he said.Future studies will try to determine whether increased flower abundance cancels out the negative effects of increased numbers of social bees combined with lower overall bee diversity later in the summer.More study is also needed to understand why social bees are so susceptible to parasites, whether they lack defenses and if they are sharing disease in close colony quarters.
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Agriculture & Food
| 2,020 |
July 23, 2020
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https://www.sciencedaily.com/releases/2020/07/200723143706.htm
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Correct dosage of methane-inhibiting additive in dairy cow feed shown in study
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The optimum amount of a methane-inhibiting supplement in dairy cattle feed has been determined by an international team of researchers, indicating that widespread use of the compound could be an affordable climate change-battling strategy, if farmers embrace it.
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Previous studies conducted at Penn State and around the world showed the addition of 3-Nitrooxypropanol -- often referred to as 3-NOP -- to the feed of dairy cows reduced their enteric methane emissions by about a third. This follow-up research showed that the optimum dose of the white, granular compound made by Dutch health and nutrition giant DSM is 150 mg/kg -- about a tablespoon in every 250 pounds of dry feed."The maximum mitigation effect was achieved with the three highest 3-NOP doses tested -- with no statistical difference among 100, 150 and 200 mg/kg," said researcher Alex Hristov, distinguished professor of dairy nutrition in Penn State's College of Agricultural Sciences. "The decrease in methane emission yield in the study ranged from 16 to 36%, and emission intensity reduction ranged from 25 to 45%."3-NOP is the only substance that has worked significantly in reducing enteric methane in cattle and not had unacceptable effects on milk production or quality, added Hristov, who has experimented with many feed additives in recent years.DSM, which has a patent on 3-NOP, has already applied to European regulators for authorization to sell the compound as a cattle feed additive. The company hopes to launch the product in the European Union soon, followed by registrations in other regions such as Brazil, Australia, New Zealand and Canada. U.S. approval, if it is granted, will come slower because 3-NOP is considered a drug here and will be regulated by the Food and Drug Administration.In this research conducted at Penn State's Dairy Teaching and Research Center, recently reported in the Methane -- a natural byproduct of digestion in ruminants -- is released by cows into the atmosphere mostly through belching. So, the results of 3-NOP trials are viewed by many scientists as critical, if the carbon footprint of dairy and beef cattle production is to be reduced to help slow climate change, explained Hristov.The climate-change contribution of methane from cow burping -- often incorrectly characterized as cow flatulence -- has been the subject of considerable derision within the U.S. However, it is taken seriously in other countries, Hristov pointed out, because the average dairy cow belches approximately 350 pounds of the potent greenhouse gas each year."But greenhouse gases from animal agriculture are just 5% of the total greenhouse gases produced in the United States -- much, much more comes from the energy and transportation sectors," he said. "So, I think it's a fine line with the politics surrounding this subject. Do we want to look at this? I definitely think that we should, and if there is a way to reduce emissions without affecting profitability on the farm, we should pursue it."It is also a matter of improving the overall efficiency of producing milk or meat, he added.For farmers to use 3-NOP, it must be economical, Hristov noted, so the research showing that relatively low dosages are effective indicates it may be, although DSM has not set a price on the feed supplement yet.But the question remains -- will the public accept it? "It's a very small synthetic molecule that is metabolized quickly and falls apart into compounds that are naturally present in the rumen of the cow," he said.
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Agriculture & Food
| 2,020 |
July 23, 2020
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https://www.sciencedaily.com/releases/2020/07/200723143702.htm
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Trends in consolidation of US agriculture with 35 years of data
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The current COVID-19 pandemic has more and more people asking about our food supply, how agriculture is moving forward, and where agriculture is going in this country. Based on the long term work of James MacDonald, a new research professor in Agricultural & Resource Economics at the University of Maryland, he is a firm believer in the Maya Angelou quote, "You can't really know where you are going until you know where you have been." In MacDonald's latest publication in
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"My background is in the field of industrial organization, so it's about competition, how industries are organized, and how they evolve," explains MacDonald. "Fundamentally with this work, I was interested in how and why production is shifting to bigger farms, because basic statistics don't give you a clear picture."As MacDonald describes in his latest paper, the trends are much more complicated than what just average acreages and farm size statistics can tell you. In order to characterize these trends, MacDonald looked at data from 1982 through 2017, showing a large aggregate shift in farming operations that hasn't been captured before in this level of detail, going beyond just industry-level data."What's been happening is a steady shift of acreage and production to larger operations that covers almost all crop and livestock commodities and that occurs steadily over three or four decades. A large part of what I was trying to do was capture that story, and then draw conclusions about what that widespread, persistent, and large pattern of consolidation meant," says MacDonald.Results show that production has in fact significantly shifted to larger farms in 60 of the 62 crop and livestock commodities analyzed over the 35-year period. This shift means fewer distinct farming operations, with smaller farms going out of business and ultimately becoming unsustainable. And with larger operations comes more acreage as well. Farms with at least 2,000 acres of cropland only operated 15% of all cropland in 1987, but now these larger farms operate 37% of all cropland. While this shift is steady across all farming industries, there are some distinctions in how it manifests."This shift happens everywhere, in fruits and vegetables as well as field crops," explains MacDonald. "But with crops, we see a more steady evolution, whereas with livestock, you get spurts of dramatic change."An example of this can be seen in dairy farming. In 1987, half of all dairy cows in the U.S. were in herds of 80 or fewer cows. But by 2017, that midpoint herd size shifted to 1,300 cows. "Consolidation in dairy is just dramatic," says MacDonald, "with shifts to much bigger farms and smaller farms going out of business. The last two years, 15% of the dairy farms in the country went out of business. The very large farms have lower costs than midsize and smaller ones, and while those lower costs reflect productivity growth and result in lower prices for the consumer, it is also pretty heartbreaking for people who have been small or midsize dairy farmers who are going out of business. In 1980 when I started this work, there were probably about 250 thousand dairy farms in the country. Today, we have 30 thousand, and it's going to keep shrinking."Despite this finding, MacDonald found that family farms still account for the vast majority of farms and farm production, with no significant movement of production toward non-family operations. According to MacDonald, consolidation encompasses shifts of production to larger family businesses, but these are still predominantly family businesses. "Every farm you see is different, and there are things that are very difficult to capture in a survey," says MacDonald. "And not only are they different, but they all have this family history that matters for how they are organized and run."So what's behind these trends? According to MacDonald, the widespread and persistent pace of this shift in the data suggests that technology plays an important role in the consolidation process. For instance, new labor-saving equipment, materials, and organizational changes now allow a single farmer or farm family to manage more acres or more livestock. Advances in technology are often expensive to implement, but cheaper in the long run, so larger operations are at an advantage and have lower overall operating costs.MacDonald thinks that we may be on the cusp of continuing technological changes, particularly in crop agriculture, through the application of precision agriculture technologies in farming. Precision agriculture technologies allow farmers to collect, analyze, and apply finely detailed information from field and herd operations. Some precision agriculture applications may favor smaller operations, but others could provide advantages to very large farming organizations. At USDA-ERS, MacDonald managed farm surveys designed to track the adoption of such technologies, and he hopes to use that survey data in the future to assess how farmers can use precision technologies, and how these technologies will affect the business of farming.
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Agriculture & Food
| 2,020 |
July 23, 2020
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https://www.sciencedaily.com/releases/2020/07/200723115855.htm
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Meet Cosmo, a bull calf designed to produce more male offspring
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Scientists at the University of California, Davis, have successfully produced a bull calf, named Cosmo, who was genome-edited as an embryo so that he'll produce more male offspring. The research was presented in a poster today (July 23) at the American Society of Animal Science meeting.
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Using the genome-editing technology CRISPR, researchers can make targeted cuts to the genome or insert useful genes, which is called a gene knock-in. In this case, scientists successfully inserted or knocked-in the cattle SRY gene, the gene that is responsible for initiating male development, into a bovine embryo. It's the first demonstration of a targeted gene knock-in for large sequences of DNA via embryo-mediated genome editing in cattle."We anticipate Cosmo's offspring that inherit this SRY gene will grow and look like males, regardless of whether they inherit a Y chromosome," said Alison Van Eenennaam, animal geneticist with the UC Davis Department of Animal Science.Van Eenennaam says part of the motivation to produce more male cattle is that male cattle are about 15 percent more efficient at converting feed into weight gain. They are more fuel-efficient than females. Additionally, they tend to be processed at a heavier weight.It could also be a win for the environment, with fewer cattle needed to produce the same amount of beef. "Ranchers could produce some females as replacements and direct a higher proportion of male cattle for market," said Joey Owen, a postdoctoral researcher in animal science who is leading the project with Van Eenennaam.The SRY gene was inserted into bovine chromosome 17, which is a genomic safe harbor site. That ensures the genetic elements function predictably and don't disrupt the expression or regulation of adjacent genes. Chromosome 17 was chosen after unsuccessful attempts to knock-in the gene on the X chromosome, which would have resulted in a bull that produced only male offspring. Cosmo is expected to produce 75 percent male offspring -- the normal 50 percent XY animals, and another 25percent XX animals that inherit the SRY gene."It took two and a half years to develop the method to insert a gene into the developing embryo and another two years to successfully establish a pregnancy," said Owen. But in April of 2020, a healthy 110-pound male calf was born."This has been a real labor of love," said Van Eenennaam.She said this is just the beginning of the research. Cosmo will reach sexual maturity in a year, and he will be bred to study if inheriting the SRY gene on chromosome 17 is sufficient to trigger the male developmental pathway in XX embryos, and result in offspring that will grow and look like males. As the Food and Drug Administration regulates gene-editing of animals as if they were drugs, Cosmo and his offspring will not enter the food supply.Other researchers on the team include James Murray, Pablo Ross, Sadie Hennig and Jason Lin with the UC Davis Department of Animal Science, and Bret McNabb and Tamer Mansour of the UC Davis School of Veterinary Medicine.This project was supported by Biotechnology Risk Assessment Grant Program from the U.S. Department of Agriculture, the California Agricultural Experiment Station at UC Davis and the USDA NIFA National Needs Graduate and Postgraduate Fellowship.
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Agriculture & Food
| 2,020 |
July 22, 2020
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https://www.sciencedaily.com/releases/2020/07/200722192150.htm
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Diets high in protein, particularly plant protein, linked to lower risk of death
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Diets high in protein, particularly plant protein, are associated with a lower risk of death from any cause, finds an analysis of the latest evidence published by
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The researchers say these findings "support current dietary recommendations to increase consumption of plant proteins in the general population."Diets high in protein, particularly protein from plants such as legumes (peas, beans and lentils), whole grains and nuts, have been linked to lower risks of developing diabetes, heart disease and stroke, while regular consumption of red meat and high intake of animal proteins have been linked to several health problems.But data on the association between different types of proteins and death are conflicting.So researchers based in Iran and the USA set out to measure the potential dose-response relation between intake of total, animal, and plant protein and the risk of death from all causes, cardiovascular disease, and cancer.They reviewed the results of 32 studies that reported risk estimates for all cause, cardiovascular, and cancer mortality in adults aged 19 or older.All studies were thoroughly assessed for bias (problems in study design that can influence results).Mathematical models were then used to compare the effects of the highest versus lowest categories of protein intake, and analyses were done to evaluate the dose-response relations between protein intake and mortality.During a follow-up period of up to 32 years, 113,039 deaths (16,429 from cardiovascular disease and 22,303 from cancer) occurred among 715,128 participants.The results show that high intake of total protein was associated with a lower risk of all cause mortality compared with low intake.Intake of plant protein was associated with an 8% lower risk of all cause mortality and a 12% lower risk of cardiovascular disease mortality. Intake of animal protein was not significantly associated with risk of cardiovascular disease and cancer mortality.A dose-response analysis of data from 31 studies also showed that an additional 3% of energy from plant proteins a day was associated with a 5% lower risk of death from all causes.Possible reasons for the beneficial effects of plant proteins include their association with favourable changes in blood pressure, cholesterol and blood sugar levels, which might help to lower the risk of conditions such as heart disease and type 2 diabetes, say the researchers.They point to some limitations, such as differences in the way studies assessed diet and the possibility that some effects may have been due to unmeasured (confounding) factors. What's more, as most of the included studies were from Western nations, the findings may not be applicable to other countries.However, strengths include the large number of participants and deaths, providing a detailed insight into the association between intake of dietary protein and risk of mortality based on the current evidence, they write."These findings have important public health implications as intake of plant protein can be increased relatively easily by replacing animal protein and could have a large effect on longevity," say the researchers.While further studies are required, these findings "strongly support the existing dietary recommendations to increase consumption of plant proteins in the general population," they conclude.
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Agriculture & Food
| 2,020 |
July 22, 2020
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https://www.sciencedaily.com/releases/2020/07/200722142736.htm
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Mitigation of greenhouse gases in dairy cattle through genetic selection
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Researchers in Spain propose mitigating methane production by dairy cattle through breeding. In an article appearing in the
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Methane from enteric fermentation is considered the main contributor to GHG coming from ruminants. These emissions contribute to global warming and represent a loss of dietary energy in ruminants. "Current selection pressure is increasing total methane production in the population of dairy cows but is reducing methane intensity (per kilogram of milk) due to higher productive levels of each cow. A reduction of methane in the breeding goals should also be included in the selection indices," said lead author Oscar González-Recio, PhD, Department of Animal Breeding, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid, Spain.Evaluation of the genetic traits and economic response of the traits in the selection index were considered in this study that used genetic parameters estimated with 4,540 records from 1,501 cows. The project was funded by the Spanish National Plan of Research, Development, and Innovation 2013-2020. While methane production is necessary to maintain rumen homeostasis, total methane emissions are expected to decrease four to six percent in 10 years due to increased milk production per cow. If annual methane production per cow is included in breeding goals and ad hoc weights are placed on methane production, GHG emission from cattle could be reduced by 20 percent in 10 years.Dr. González-Recio added that "increasing per-cow productivity may reduce the number of cows needed per billion kilograms of milk produced, contributing to mitigation of GHG emissions, but this is not enough. If no action is taken, the genetic potential for methane production is expected to increase."While the biological limit of methane production remains unknown, this study shows the potential for including environmental traits in selection indices while retaining populations of cows that are profitable for producers.
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Agriculture & Food
| 2,020 |
July 22, 2020
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https://www.sciencedaily.com/releases/2020/07/200722112735.htm
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Science sweetens stingless bee species honey health claims
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Science has validated Indigenous wisdom by identifying a rare, healthy sugar in native stingless bee honey that is not found in any other food.
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University of Queensland organic chemist Associate Professor Mary Fletcher said Indigenous peoples had long known that native stingless bee honey had special health properties."We tested honey from two Australian native stingless bee species, two in Malaysia and one in Brazil and found that up to 85 per cent of their sugar is trehalulose, not maltose as previously thought," she said.Dr Fletcher said trehalulose was a rare sugar with a low glycaemic index (GI), and not found as a major component in any other foods."Traditionally it has been thought that stingless bee honey was good for diabetes and now we know why -- having a lower GI means it takes longer for the sugar to be absorbed into the blood stream, so there is not a spike in glucose that you get from other sugars," Dr Fletcher said."Interestingly trehalulose is also acariogenic, which means it doesn't cause tooth decay."Dr Fletcher said the findings would strengthen the stingless bee honey market and create new opportunities."Stingless bee honey sells now for around AUD $200 per kilogram, which is up there with the price of Manuka and Royal Jelly honey," she said."The high commercial value also makes it a risk for substitution, where people could sell other honey as stingless bee honey, or dilute the product."But due to this research, we can test for this novel sugar, which will help industry to set a food standard for stingless bee honey."People have patented ways of making trehalulose synthetically with enzymes and bacteria, but our research shows stingless bee honey can be used as a wholefood on its own or in other food to get the same health benefits."The work of Dr Fletcher and the research team has led to a new project funded by AgriFutures Australia and supported by the Australian Native Bee Association.Working with Dr Natasha Hungerford from UQ's Queensland Alliance for Agriculture and Food Innovation and Dr Tobias Smith from the School of Biological Sciences the new project will investigate storage and collection, to optimise the trehalulose content of Australian stingless bee honey.Stingless bees (Meliponini) occur in most tropical and sub-tropical regions, with more than 500 species across Neotropical, Afrotropical and Indo-Australian regions.Like the well-known Apis mellifera honeybees, stingless bees live in permanent colonies made up of a single queen and workers, who collect pollen and nectar to feed larvae within the colony.Dr Fletcher said keeping native stingless bees was gaining in popularity in Australia, for their role as pollinators as well as for their unique honey.As well as having health benefits, stingless bee honey is valued for its flavour and is in high demand from chefs.
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Agriculture & Food
| 2,020 |
July 21, 2020
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https://www.sciencedaily.com/releases/2020/07/200721114723.htm
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Site-directed mutagenesis in wheat via haploid induction by maize
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A new study, which has recently been published in the
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For exemplification of this principle, new allelic variants were generated for the wheat genes BRASSINOSTEROID-INSENSITIVE 1 (BRI1) and SEMIDWARF 1 (SD1) which are involved in the regulation of the agronomically important trait plant height.In total, 15 independent target gene-specific mutants were identified out of 174 wheat plants. Mutants were obtained in six wheat backgrounds, including the three spring-type common wheats BW, W5 and K15, the winter-type bread wheat S96, as well as the two durum wheats D6 and D7. Mutations were found in all three genomic target motifs addressed. None of the 15 mutants carried any transgene. The efficiency in mutant plant formation ranged from 3.6% to 50%."The major advances achieved in the present study include (1) much reduced genotype dependence, (2) the opportunity of creating a whole variety of wheat plants carrying different allelic variants of the target gene using just one cas9/gRNA-transgenic maize plant as well as (3) the production of target gene-specific mutants that are instantly true-breeding and generally free of any transgenes," says Dr. Nagaveni Budhagatapalli who played a key role in the study conducted at the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben.However, there is still room for increasing the efficiency of this approach, e.g. by stronger Cas9 and gRNA expression at the relevant timepoint or by the development of improved protocols for in planta production of doubled haploids.
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Agriculture & Food
| 2,020 |
July 21, 2020
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https://www.sciencedaily.com/releases/2020/07/200721102203.htm
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Recycling Japanese liquor leftovers as animal feed produces happier pigs and tastier pork
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Tastier pork comes from pigs that eat the barley left over after making the Japanese liquor shochu. A team of professional brewers and academic farmers state that nutrients in the leftover fermented barley may reduce the animals' stress, resulting in better tasting sirloin and fillets.
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"Kyushu, in Western Japan is well-known historically for making shochu and for its many pig farms. We hope collaborative research projects like ours can directly benefit the local community and global environment," said Yasuhisa Ano, the first author of the research paper published in Food Chemistry. Ano is affiliated with the Kirin Central Research Institute at Kirin Holdings Co., Ltd.Currently, the mash of leftovers that remains after distilling out the alcohol is considered industrial waste and is often disposed of in ways that create more climate-changing carbon dioxide. Feeding distillation leftovers to farm animals can improve the animals' quality of life, lower farmers' and brewers' costs, appeal to discerning foodies, and benefit the environment by reducing food waste.Japanese shochu can be made from barley, potatoes, rice or other starches first decomposed with mold, then fermented with yeast, and finally distilled to an alcohol content usually greater than 20 percent. Incidentally, Japanese sake is a fermented drink always made from rice with an alcohol content typically around 15 percent.Researchers at the University of Tokyo fed six pigs a standard diet supplemented with shochu distillation remnants, the dried mixture of barley, mold and yeast left over after distilling out the shochu. Pigs fed shochu remnants from age 3 to 6 months had higher amounts of antibodies called IgA in their saliva, indicating that shochu remnants kept the pigs healthier than the standard diet. Additionally, pigs fed shochu remnants had lower stress levels than pigs fed the normal diet supplemented with fresh barley, as measured by the amount of cortisol, a common stress hormone, in their saliva.Other studies have linked healthier responses to stress to two protein building blocks called leucine and histidine peptides, which barley shochu contains in abundance.The UTokyo research team performed additional tests in mice to study the effect of barley shochu distillation remnants on stress. Mice that ate the distillation remnants just once directly before a stressful event returned to normal behavior faster than other mice. The mice who ate the shochu remnants also had normal levels of dopamine in their brains after the stressful event, indicating a better response to stress.Researchers suspected that the lower stress and better health throughout the pigs' lives created higher quality meat, but they asked flavor experts from Kirin for a blind taste test.According to the experts' palates, both sirloin and fillet cuts of pork from the shochu remnant-fed pigs were higher quality than meat from pigs that ate the standard diet: better umami, tenderness, juiciness and flavor."We saw no difference in the pigs' weight gain between the two diets and the pigs were slaughtered at the standard six months of age, meaning any difference in the quality of meat was not because of a difference in quantity of fat," said Associate Professor Junyou Li from the University of Tokyo, a co-author of the research publication.That higher quality taste was likely due to chemical differences in the meat. Fat from the higher-quality meat melted at lower temperatures, which creates the delicious melt-in-your-mouth texture. That fat was also made up of a higher percentage of oleic acid, an unsaturated fatty acid linked by other studies to improved levels of "healthy" LDL cholesterol."We hope that identifying these benefits for the animals and creating a premium tasting product for consumers will increase farmers' motivation to try a new diet for their pigs," said Professor Masayoshi Kuwahara, director of the University of Tokyo Animal Resource Science Center and last author of the research publication.
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Agriculture & Food
| 2,020 |
July 20, 2020
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https://www.sciencedaily.com/releases/2020/07/200720152409.htm
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Returning to farming's roots in the battle against the 'billion-dollar beetle'
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Nicknamed the "billion-dollar beetle" for its enormous economic costs to growers in the United States each year, the western corn rootworm is one of the most devastating pests farmers face.
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"They are quite insidious. They're in the soil gnawing away at the roots and cutting off the terminal ends of the roots -- the lifeblood of corn," said Bruce Tabashnik, Regents Professor and head of the University of Arizona Department of Entomology. "And if they're damaging enough, the corn plants actually fall over."Genetically modified crops have been an important tool in the battle against pests such as these, increasing yields while reducing farmers' reliance on broad-spectrum insecticides that can be harmful to people and the environment.Corn was genetically engineered to produce proteins from the bacterium Bacillus thuringiensis, or Bt, that kill rootworm larvae but are not toxic to humans or wildlife. The technology was introduced in 2003 and has helped keep the corn rootworm at bay, but the pest has begun to evolve resistance."So, now the efficacy of this technology is threatened and if farmers were to lose Bt corn, the western corn rootworm would become a billion-dollar pest again," said Yves Carrière, a professor of entomology in the College of Agriculture and Life Sciences.Carrière is lead author of a study to be published in Crop rotation, the practice of growing different crops in the same field across seasons, has long been used for pest control. In 2016, the U.S. Environmental Protection Agency mandated crop rotation as a primary means of reducing the damage to Bt corn fields caused by resistant corn rootworms, but there have been limited scientific studies to support the efficacy of this tactic.Carrière and his team rigorously tested this approach by analyzing six years of field data from 25 crop reporting districts in Illinois, Iowa and Minnesota -- three states facing some of the most severe rootworm damage to Bt cornfields.The results show that rotation works. By cycling different types of Bt corn and rotating corn with other crops, farmers greatly reduced rootworm damage.Most notably, crop rotation was effective even in areas of Illinois and Iowa where rootworm resistance to corn and soybean rotation had been previously reported.According to the study, crop rotation provides several other benefits as well, including increased yield, reductions in fertilizer use and better pest control across the board."Farmers have to diversify their Bt crops and rotate," Carrière said. "Diversify the landscape and the use of pest control methods. No one technology is the silver bullet."Tabashnik relates the research back to UArizona's work with the pink bollworm, in which researchers spearheaded a management program to suppress the pink bollworm's resistance to Bt cotton."The key to eradicating pink bollworm in the U.S. was integrating Bt cotton with other control tactics," Tabashnik said. "We succeeded, whereas this voracious invasive pest rapidly evolved resistance to Bt cotton in India, where the genetically engineered crop was used alone."In collaboration with cotton growers, UArizona scientists sustained the efficacy of Bt cotton against pink bollworm by establishing the "refuge strategy," in which non-Bt crops are planted near Bt crops to allow survival of susceptible insects. The strategy has become the primary approach used worldwide to delay the adaptation of insect pests to genetically engineered crops.Although farmers have used refuges to thwart the rootworm's resistance to Bt corn, this strategy alone has proven insufficient against the pest."During the last decade, we have learned that refuges are often not sufficient to delay resistance in pests like the corn rootworm," Carrière said. "It would be wise to diversify management tactics before such pests evolve resistance. This approach, called integrated pest management, is vital for preserving the benefits of biotechnology."In many ways, the study reaffirms traditional agricultural knowledge."People have been rotating crops since the dawn of farming. The new agricultural technology we develop can only be sustained if we put it in the context of things we've known for thousands of years," Tabashnik said. "If we just put it out there and forget what we've learned in terms of rotating crops, it won't last."The authors emphasize that increasing crop rotation is essential for sustaining the economic and environmental benefits provided by rootworm-active Bt corn. During the six years of the study, the average percentage of corn rotated to other crops per state ranged from about 55-75%."This is one of the most important applications of Bt crops in the United States," Carrière said. "If we lose this technology and we start using soil insecticides again, it's going to have a big negative environmental impact."
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Agriculture & Food
| 2,020 |
July 20, 2020
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https://www.sciencedaily.com/releases/2020/07/200720103320.htm
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New research reveals antifungal symbiotic peptide in legume
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Fungal diseases cause substantial losses of agricultural harvests each year. The fungus Botrytis cinerea causing gray mold disease is a major problem for farmers growing strawberries, grapes, raspberries, tomatoes and lettuce. To mitigate the problem, they often resort to applying chemical fungicides which can lose their effectiveness over time. Danforth Center scientists, Dilip Shah, PhD, research associate member, Siva Velivelli, PhD, postdoctoral associate, Kirk Czymmek, PhD, principal investigator and director, Advanced Bioimaging Laboratory and their collaborators at the Pacific Northwest National Laboratory have identified a sub class of peptides in the nodules of the legume, Medicago truncatula that proved effective in inhibiting growth of the fungus causing gray mold. The results of their research, Antifungal symbiotic peptide NCR044 exhibits unique structure and multifaceted mechanisms of action that confer plant protection, were recently published in the journal,
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"We are excited about the possibility of developing this class of peptides as a spray-on fungicide that would provide farmers with an environmentally friendly alternative to chemical fungicides for pre- and post-harvest management of fungal diseases," said Dilip Shah. "When applied to crops, the peptides will eventually break down to amino acids in the soil and be used by beneficial microbes as an energy source."Medicago truncatula is a relative of alfalfa. Shah and his team produced recombinantly large quantities of the highly charged NCR044 peptide that is expressed in the nodules of this legume. They then applied the peptide in low concentrations to tobacco and tomato plants in the lab and challenged the plants with the gray mold fungus. The plants showed significant protection from this fungal disease.To understand the antimicrobial mechanism within the cell, they collaborated with Czymmek, who is also a mycologist and has studied fungal cell biology for many years. Using time-lapse confocal and super resolution microscopy, the team was able to observe dynamically how the peptide binds to fungal spores and germlings, how it is internalized and where it goes inside the fungal cell. One key finding here was the confirmation that the peptide concentrated in the nucleolus, the organelle where ribosomal assembly takes place."It was a pleasure to work with Dilip and his team. As a young scientist, Siva, was able to move diligently across a very diverse set of platforms and techniques, following-up on leads from the scientific data. Ultimately, he was able to apply these corroborating techniques and uncover significant new information to create robust conclusions about the research project," said Czymmek, "It was really great science."The unique team of scientists with expertise in fungal and plant cell biology combined with advanced imaging capabilities allowed them to make critical interpretations and confirm their hypotheses. Their collaborator and co-author on the paper, Garry Buchko, PhD at the Pacific Northwest National Laboratory solved the first three-dimensional structure of a nodule-specific peptide revealing a largely disordered, and highly dynamic, peptide structure containing a short anti-parallel ?-sheet, tiny ?-helix, and when oxidized, two stabilizing disulfide bonds.A portion of the project was funded by TechAccel. Shah and Czymmek will continue their research and have applied to the National Science Foundation for a grant to further explore how antifungal nodule-specific peptides kill harmful fungal pathogens in vitro and in planta.
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Agriculture & Food
| 2,020 |
July 20, 2020
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https://www.sciencedaily.com/releases/2020/07/200720102052.htm
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Soil microbes could promote better farm outputs
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In hotter, dryer conditions with climate change, a secret agent for more sustainable agricultural production could lie in harvesting the diverse beneficial soil microbiome in native bushland settings, scientists say.
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New research from CSIRO, Flinders University and La Trobe University highlights the importance of soil biological health and further potential to use organic rather than chemical farm inputs for crop production."We know antibiotics are very useful in pharmaceuticals, and actinobacteria found plentifully and in balance in various natural environments play a vital role in the plant world," says lead author Dr Ricardo Araujo, a visiting Flinders University researcher from the University of Porto in Portugal."These actinobacterial communities contribute to global carbon cycling by helping to decompose soil nutrients, increase plant productivity, regulate climate support ecosystems -- and are found in abundance in warm, dry soil conditions common in Australia."A new article in Other researchers from the La Trobe University AgriBio Centre contributed to the analysis of 2211 actinobacterial operational taxonomic units (OTUs) mapped in mainland Australia, and 490 OTUs from Tasmania, King Island, Christmas Island and Northern Antarctica.CSIRO Agriculture and Food senior principal research scientist, Associate Professor Gupta Vadakattu, says the dfferences we found between mainland Australia and more remote locations showed how agriculture has had an impact on the diversity of actinobacterial."Our study shows how native vegetation is a reservoir for these important soil microorganisms, and this could be used to enrich adjoining agricultural soils," says Associate Professor Vadakattu, adding an intriguing finding was the similarity in actinobacteria profiles of King Island and areas of Antarctica where these continents were once connected."Patterns of actinobacteria dispersal suggest only a small fraction of them had the capability of spreading throughout the Southern Hemisphere, especially across oceans."Flinders University colleague Professor Chris Franco, says biotechnology has long benefited from actinobacteria for human and animal health products, and increasingly in sustainable agriculture."The diversity and structure of soil antinobacterial communities are influenced by multiple factors, representing one of the most abundant soil bacterial taxa across a diverse range of ecological regions -- from deserts to Antarctica," Professor Franco says."There is much more we need to learn about their potential in primary production and retaining and incorporating native plants in our ecosystems."
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Agriculture & Food
| 2,020 |
July 20, 2020
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https://www.sciencedaily.com/releases/2020/07/200720093251.htm
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Scientists supercharge shellfish to tackle vitamin deficiency in humans
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Cambridge scientists have developed a new way to fortify shellfish to tackle human nutrient deficiencies which cause severe health problems across the world. The team is now working with major seafood manufacturers to further test their microencapsulation technology, or "Vitamin Bullets."
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Over two billion people worldwide are nutrient deficient, leading to a wide range of serious health problems. Fortifying food with micronutrients is already an industry standard for enhancing public health but now scientists at Cambridge's Department of Zoology have teamed up with Cambridge-based company BioBullets to supercharge one of the world's most healthy and sustainable sources of animal protein: bivalve shellfish such as oysters, clams and mussels.Dr David Aldridge and PhD student David Willer have produced the world's first microcapsule specially designed to deliver nutrients to bivalves which are beneficial to human health. These "Vitamin Bullets" -- manufactured under patent by Aldridge's company, BioBullets -- are tailored for optimal size, shape, buoyancy and to appeal to shellfish.This breakthrough, described in a study published today in the journal In their Cambridge laboratory, the scientists trialled Vitamin A and D fortified microcapsules on over 100 oysters to identify the optimal dose. They also established that this should be fed for 8 hours towards the end of "depuration," the period in which bivalves are held in cleansing tanks after being harvested.The team found that fortified oysters delivered around 100 times more Vitamin A, and over 150 times more Vitamin D, than natural oysters. Even more importantly, they dramatically outperformed salmon, one of the best natural sources of these vitamins. The fortified oysters provided more than 26 times more Vitamin A and over 4 times more Vitamin D than salmon. The scientists found that a serving of just two of their supercharged shellfish provided enough Vitamin A and D to meet human Recommended Dietary Allowance (RDAs).Vitamin A and D deficiencies pose a particularly serious public health challenge -- in Ghana more than 76% of children are Vitamin A deficient, causing widespread mortality and blindness. In India, 85% of the population is Vitamin D deficient, which causes cardiovascular diseases, osteoporosis, and rickets. Even in the US, over 40% of people are Vitamin D deficient.David Willer said: "We have demonstrated a cheap and effective way to get micronutrients into a sustainable and delicious source of protein. Targeted use of this technology in regions worst affected by nutrient deficiencies, using carefully selected bivalve species and micronutrients, could help improve the health of millions, while also reducing the harm that meat production is doing to the environment."David Aldridge said: "We are very excited about BioBullets' potential. We are now establishing links with some of the world's biggest seafood manufacturers to drive a step change in the sustainability and nutritional value of the seafood that we consume."Bivalves have a higher protein content than beef, are a rich source of omega-3 fatty acids, and have some of the highest levels of key minerals of all animal foods. Nevertheless, the nutrients that they deliver naturally is unlikely to solve global deficiencies. These shellfish are also highly sustainable to farm, having a far lower environmental footprint than animal meat or fish, and lower even than many plant crops such as wheat, soya, and rice.Bivalves are a highly affordable food source when produced at large scale and the global market is rapidly expanding. Production in China alone has grown 1000-fold since 1980 and there is great potential to sustainably expand bivalve aquaculture worldwide, with over 1,500,000 km2 available for sustainable low-cost industry development, particularly around the west coast of Africa and India.The researchers point out that consumers in poorer regions where vitamin deficiencies are most prevalent are more likely to buy slightly more expensive fortified food than to make additional purchases to take supplement pills. They calculate that fortification adds just $0.0056 to the cost of producing a single oyster.
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Agriculture & Food
| 2,020 |
July 16, 2020
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https://www.sciencedaily.com/releases/2020/07/200716111634.htm
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Timing key in understanding plant microbiomes
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Oregon State University researchers have made a key advance in understanding how timing impacts the way microorganisms colonize plants, a step that could provide farmers an important tool to boost agricultural production.
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The findings, published in the journal While scientists have studied microbes living in plants for decades, it has only been in the last 10 years or so that advances in DNA sequencing technology have it made it possible to characterize the unseen diversity of plant microbiomes with more precision. The surge in research involving the plant microbiome coincides with a spike in research involving the human microbiome and its role in human health and disease.Understanding how plant microbiomes form is important because some microorganisms are beneficial and others are harmful to plants. Some factors shaping microbiome composition are predictable, like the relative humidity of the environment, or the thickness of the protective, waxy layer of cells on the leaf surface.However, much of the variation in microbiome composition remains unexplained. The Oregon State research, led by Posy Busby, an assistant professor in the Department of Botany and Plant Pathology, and Devin Leopold, a postdoctoral fellow in her lab, unravels some of those mysteries.In this study, Busby and Leopold explored one process that likely contributes to this unexplained variation: the order in which microorganisms colonize plants.The research was unique in that they studied plants with different genetic backgrounds, in this case black cottonwood trees collected throughout the Cascade Range in the Pacific Northwest, and also exposed those plants to leaf rust, a disease-causing fungus.They found that the order the microorganisms reached the plant had a significant impact on microbiome composition and how susceptible the plant was to disease. Additionally, the researchers found that this random variation in arrival order of microorganisms may be more important for highly disease-susceptible plants, which have not evolved their own effective defense strategies.Farmers have a long history of applying beneficial microorganisms to crops. This research provides them with more information about which plant cultivars may be best suited for microbial biocontrol, and how to best time treatments to prevent disease in plants."Our hope is that our findings will translate into tools for combatting plant disease that aren't limited to planting only disease-resistant cultivars," Busby said. "Because maintaining diversity in our crops is essential to the long-term sustainability of our agricultural systems."This research was supported by the U.S. Department of Energy's Office of Biological and Environmental Research and the OSU Department of Botany and Plant Pathology in the College of Agricultural Sciences.
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Agriculture & Food
| 2,020 |
July 15, 2020
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https://www.sciencedaily.com/releases/2020/07/200715142355.htm
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Urban bees: Pollinator diversity and plant interactions in city green spaces
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With the right mix of plants, urban green spaces can be a rich habitat to support diverse pollinators, according to a study published July 15, 2020 in the open-access journal
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With cities expanding and insect populations rapidly declining across the globe, incorporating insect-friendly green spaces into urban design is a critical step to bolster pollinator populations -- intrinsically valuable in their own right as well as necessary for more than 75 percent of the world's food supply. In this study, Daniels and colleagues surveyed diverse green spaces across the German city of Aachen to assess plant-pollinator interactions within an urban environment.The authors categorized Aachen's green spaces into four categories: recreational parks; community gardens; the cemetery; and a "representative" park in the city center, with a rural reference site at Aachen's outskirts as a control -- focusing on two different park elements within each study site, flower beds and insect-pollinating trees (specifically Tilia, or linden trees). Daniels and colleagues then surveyed these sites to observe visiting pollinators in thirty-minute intervals from 10AM-5PM in sunny, non-windy conditions from May to August 2016 (with the linden trees observed during their bloom period, from June 21-July 15) -- recording 7723 total interactions between pollinators and plants.At the rural control site, the average number of observed pollinator visits was 46.2±14.6 within 30 minutes. Community gardens showed similar levels of visitation (43.7±23.0 per 30 minutes), but average insect visits for the representative park, recreational parks, and cemetery were significantly lower (mean visitation rates of 21.0±12.6, 20.8±15.5 and 17.8±10.1 respectively). The authors note that the composition of pollinators varied across park types as well, with community gardens and the rural site showing similar -- and significantly higher -- frequencies of wild bee and hoverfly visits. In contrast, the visitation rates of flowering linden trees showed similar frequencies for all tested park types (with an average ranging from 12.9 visits/30 minutes (cemetery site) to 16.4 visits/30 minutes (recreational parks). The linden trees also showed higher rates of bumblebee and honeybee visitors as compared to other pollinators.The authors note that though this study only ran during the peak bloom season, from May to August, future studies should run year-round in order to accurately gauge pollinator behavior. They also note that recreational parks showed comparably low visitation rates of pollinators as compared to other green spaces in Aachen, but would likely have high potential to provide additional diverse resources for pollinators via additional tree plantings or small flower beds -- and encourage future policies for integrated management of urban parks as key habitats for pollinators.The authors add: "In these times of global insect decline, cities and especially urban green spaces show a high potential to provide habitats for a variety of insect groups. The design and management of urban green spaces have a strong impact on the diversity and abundance of pollinators in cities."
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Agriculture & Food
| 2,020 |
July 15, 2020
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https://www.sciencedaily.com/releases/2020/07/200715095452.htm
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New study shows how plants regulate their growth-inhibiting hormones to survive
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In a world with a consistently growing population and a climate crisis, food shortage is a looming threat. To alleviate this threat, crop scientists, botanists, genetic engineers, and others, have been exploring ways of boosting crop productivity and resilience. One way to control plant growth and physiology is to regulate the levels of "phytohormones" or plant hormones.
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However, much remains to be known about the mechanisms that underlie this hormonal regulation in plants, limiting advancement in this direction. Now, in a study led by Nagoya University Japan, a team of scientists has discovered, using rice plants as the study model, that a process called "allosteric regulation" is involved in maintaining the phytohormonal balance in plants. Their findings, published in Plants survive by adapting their development and physiology to their surrounding environments by controlling the levels of enzymes driving the synthesis of two phytohormones, gibberellin and auxin. Enzymes are proteins that bind to one or more reactant chemicals and speed up a reaction process. The binding site is called the activation site. In 1961, it was discovered that in bacteria, enzyme activity is enhanced or inhibited via allosteric regulation, which essentially is the binding of a molecule called the "effector" at a site other than the active site of the enzyme. In allosteric regulation, the structure of the enzyme changes to either support or hinder the reaction that the enzyme enables.Professor Miyako Ueguchi-Tanaka of Nagoya University, lead scientist in the team that has now observed allosteric regulation in plants for the first time, explains their research findings, ''We used a technique called X-ray crystallography and found that, as molecules of the enzymes (gibberellin 2-oxidase 3 [GA2ox3], and auxin dioxygenase [DAO]) bind to gibberellin and auxin (respectively), they interact among themselves and form 'multimeric' structures, comprising four and two units respectively. As the amounts of gibberellin and auxin increase, so does the rate of multimerization of the enzymes. And multimerization enhances the activity of the enzymes, enabling greater degradation of gibberellin and auxin. Synchronous structural changes and activity enhancement are typical of allosteric-regulation events."The scientists further carried out "phylogenetic" analysis of GA2ox3 and DAO, which revealed that plants independently developed this hormone regulation mechanism at three separate time-points over the course of the evolutionary process.Enthusiastic about the future prospects of these findings, Prof Ueguchi says, "The activity control system revealed here can be used to artificially regulate the activity of the growth inactivating hormones in plants. As a result, rice crop productivity can be improved and high-biomass plants can be produced in the event of food shortage or an environmental crisis."Of course, this study is only a stepping stone for now, and much remains to be done to see how the findings of this study can be applied practically in agricultural lands. However, these findings certainly are encouraging, and they signal the coming of a new era of sustainable development fueled by biotechnological advancements.
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Agriculture & Food
| 2,020 |
July 16, 2020
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https://www.sciencedaily.com/releases/2020/07/200716144740.htm
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About 94 per cent of wild bee and native plant species networks lost
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Climate change and an increase in disturbed bee habitats from expanding agriculture and development in northeastern North America over the last 30 years are likely responsible for a 94 per cent loss of plant-pollinator networks, York University researchers found.
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The researchers, corresponding author Professor Sandra Rehan of the Faculty of Science and grad student Minna Mathiasson of the University of New Hampshire, looked at plant-pollinator networks from 125 years ago through present day. The networks are comprised of wild bees and the native plants they historically rely on, although most of those have now been disrupted.About 30 per cent of plant-pollinator networks were completely lost, which translates to a disappearance of either the bees, the plants or both. In another 64 per cent of the network loss, the wild bees, such as sweat or miner bees, or native plants, such as sumac and willow, are still present in the eco-system, but the bees no longer visit those plants. The association is gone.The remaining six per cent of the plant-pollinator networks are stable or even thriving with pollinators such as small carpenter bees, which like broken stems for nest making."There are several reasons for the losses in the networks. Climate change is likely the biggest driver. We know that over the last 100 years or so annual temperatures have changed by two and a half degrees. This is enough to alter the time when certain native plants bloom," says Rehan."For a bee that's out for months on end or is a generalist pollinator, this isn't such a critical mismatch, but for a bee that's only out for two weeks of the year and only has a few floral hosts, this could be devastating." An increase in non-native species of bees and invasive species of plants, which have displaced some of the native species, is another reason for the decline in networks."We are getting a lot of invasive species and new records of invasive species every year. This is usually accidentally through trade and through ornamental plants," says Rehan.A lot of these bees live in stems, so it's easy to import plants with non-native bee species without knowing it. "We can actually show routes and means of invasion biology," she says.These bees are following shipping routes from one continent to the other around the world, including North America through ornamental plants for our gardens.The researchers say an increase in habitat restoration and native flowering plants in agricultural landscapes are critical for improving wild bee biodiversity, but also food security for humans.Bees and other pollinators are worth hundreds of billions of dollars globally by pollinating the crops we eat, and wild bees are at the top of the list believed to pollinate more than 87 per cent or 308,006 flowering plant species. Many of these are economically important commercial crops, such as apples and blueberries."There is an urgent need to gain a deeper understanding of the environmental circumstances affecting these wild pollinator populations and their specialised, evolutionary relationships with plant communities," says Rehan. "Plant pollinator webs are dependent on changes in the landscape, so knowing how these networks are shaped is important for all regional habitats."Previous recent research by Rehan and team looked at 119 wild bee species over 125 years and found 14 declining and eight increasing species. All of the wild bee species in decline are native and over half experienced significant range (latitude and elevation) shifts.
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Agriculture & Food
| 2,020 |
July 14, 2020
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https://www.sciencedaily.com/releases/2020/07/200714101253.htm
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Pesticide mixtures a bigger problem than previously thought
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New research led by The University of Queensland has provided the first comprehensive analysis of pesticide mixtures in creeks and rivers discharging to the Great Barrier Reef.
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UQ's School of Earth and Environmental Sciences researcher Associate Professor Michael Warne conducted the study with the Queensland Department of Environment and Science, and analysed 2600 water samples from 15 waterways that discharge into the Great Barrier Reef lagoon over a four-year period."While I knew many water samples would contain mixtures, I was shocked to find that essentially every sample contained mixtures of pesticides," Dr Warne said."We found 99.8 per cent of the samples contained pesticide mixtures with up to 20 pesticides in any single water sample."The issue with having mixtures of pesticides is that as the number of pesticides increases the impact to aquatic ecosystems generally increases."This work strongly supports the inclusion of the pesticide reduction target in the Reef 2050 Water Quality Improvement Plan which aims to protect at least 99 per cent of aquatic organisms at the mouths of rivers from the adverse effects of all pesticides."Dr Warne said the best way to address the problem of pesticides and pesticide mixtures in run-off was to work with land managers, share information and help them to improve their pesticide management practices."We are doing just that with other partners including Farmacist, James Cook University and the Department of Environment and Science through Project Bluewater which is funded by the Great Barrier Reef Foundation," he said."This project is working with 70 sugar cane farmers in the Barratta Creek and Plane River catchments to improve their pesticide management and application, upgrade equipment, reduce pesticide use and switch to using lower risk pesticides."We have found the farmers involved to be very eager to engage with the science -- they have embraced the challenge and are making significant steps toward improvement."We are looking to expand this project to include considerably more farmers in more catchments and make more rapid progress in reducing pesticide losses to waterways."There is always hope, but this study reveals the pesticide situation is more complex than we previously realised."
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Agriculture & Food
| 2,020 |
July 14, 2020
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https://www.sciencedaily.com/releases/2020/07/200714101240.htm
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Drones and artificial intelligence show promise for conservation of farmland bird nests
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Farmland bird species are declining over most of Europe. Birds breeding on the ground, are particularly vulnerable because they are exposed to mechanical operations, like ploughing and sowing, which take place in spring and often accidentally destroy nests.
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Researchers flew a drone carrying a thermal camera over agricultural fields to record images. These were then fed to an artificial intelligence algorithm capable of accurately identifying nests, a first step to aid their protection. Researchers tested the system in Southern Finland near University of Helsinki's Lammi Biological Station, using wild nests with eggs of the Lapwing Vanellus vanellus."We have been involved in conservation of ground-nesting farmland birds for years, and realized how difficult it is to locate nests on the ground. At least at high latitudes, the temperature of these nests is typically higher than that of the surrounding environment. Hence, we thought that thermal cameras could assist. A small pilot study indicated that thermal vision is hampered by vegetation and objects on the ground. Therefore to make this an efficient system, we thought that the camera could be flown using a drone, and artificial intelligence could help to analyse the resulting thermal images. We show that this works. However, the system performed best under cloudy and cold conditions, and on even grounds," says Andrea Santangeli, an Academy of Finland fellow at the Finnish Museum of Natural History Luomus, University of Helsinki.It is possible to map in near real-time the spread of diseases on crops in agricultural areas using drones with various sensors. The latter is an integral part of precision agriculture, a new way of crop production that makes large use of drone technology to monitor crops and maximize production efficiency.Studies like this one can help pave the way to integrate bird nest detection within the drone borne sensors used in precision agriculture, and automate a system for saving those nests."The conservation community must be ready to embrace technology and work across disciplines and sectors in order to seek efficient solutions. This is already happening, with drone technology becoming rapidly popular in conservation. A next and most challenging step will be to test our system in different environments and with different species. Our auspice is that this system will be, one day, fully integrated into agricultural practices, so that detecting and saving nests from mechanical destruction will become a fully automated part of food production," says Andrea Santangeli.
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Agriculture & Food
| 2,020 |
July 14, 2020
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https://www.sciencedaily.com/releases/2020/07/200714082842.htm
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Space to grow, or grow in space -- how vertical farms could be ready to take-off
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Vertical farms with their soil-free, computer-controlled environments may sound like sci-fi. But there is a growing environmental and economic case for them, according to new research laying out radical ways of putting food on our plates.
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The interdisciplinary study combining biology and engineering sets down steps towards accelerating the growth of this branch of precision agriculture, including the use of aeroponics which uses nutrient-enriched aerosols in place of soil.Carried out by the John Innes Centre, the University of Bristol and the aeroponic technology provider LettUs Grow, the study identifies future research areas needed to accelerate the sustainable growth of vertical farming using aeroponic systems.Dr Antony Dodd, a group leader at the John Innes Centre and senior author of the study, says: "By bringing fundamental biological insights into the context of the physics of growing plants in an aerosol, we can help the vertical farming business become more productive more quickly, while producing healthier food with less environmental impact."Jack Farmer, Chief Scientific Officer at LettUs Grow and one of the authors of the study, adds: "Climate change is only going to increase the demand for this technology. Projected changes in regional weather patterns and water availability are likely to impact agricultural productivity soon. Vertical farming offers the ability to grow high value nutritious crops in a climate resilient manner all year round, proving a reliable income stream for growers."Vertical farming is a type of indoor agriculture where crops are cultivated in stacked systems with water, lighting and nutrient sources carefully controlled.It is part of a rapidly growing sector supported by artificial intelligence in which machines are taught to manage day to day horticultural tasks. The industry is set to grow annually by 21% by 2025 according to one commercial forecast (Grand View Research, 2019).Green benefits include better use of space because vertical farms can be sited in urban locations, fewer food miles, isolation from pathogens, reduction in soil degradation and nutrient and water recapturing and recycling.Vertical farms also allow product consistency, price stabilization, and cultivation at latitudes incompatible with certain crops such as the desert or arctic."Vertical systems allow us to extend the latitude range on which crops can be grown on the planet, from the deserts of Dubai to the 4-hour winter days of Iceland. In fact, if you were growing crops on Mars you would need to use this kind of technology because there is no soil," says Dr Dodd.The study, which appears in the journal These seek to understand:Why aeroponic cultivation can be more productive than hydroponic or soil cultivation.The relationship between aeroponic cultivation and 24-hour circadian rhythms of plants.Root development of a range of crops in aeroponic conditions.The relationship between aerosol droplet size and deposition and plant performance.How we can establish frameworks for comparing vertical farming technologies for a range of crops.How aeroponic methods affect microbial interactions with plant roots.The nature of recycling of root exudates (fluids secreted by the roots of plants) within the nutrient solutions of closed aeroponic systems.The report argues that a driver of technological innovation in vertical farms is minimizing operation costs whilst maximizing productivity -- and that investment in fundamental biological research has a significant role.Dr Dodd's research area covers circadian rhythms -- biological clocks which align plant physiology and molecular processes to the day to day cycle of light and dark. He recently completed a year-long Royal Society Industry Fellowship with LettUs Grow.This involved combining Dr Dodd's expertise in circadian rhythms and plant physiology with the work of LettUs Grow's team of biologists and engineers to design optimal aeroponic cultivation regimens. This is a key area of investigation as these molecular internal timers will perform differently in vertical farms.Aeroponic platforms are often used to grow high value crops such as salads, pak choi, herbs, small brassica crops, pea shoots and bean shoots. LettUs Grow are also working on growth regimens for fruiting and rooting crops such as strawberries and carrots, as well as aeroponic propagation of trees for both fruit and forestry.John Innes Centre researchers have bred a line of broccoli adapted to grow indoors for a major supermarket and one of the aims of research will be to test how we can genetically tune more crops to grow in the controlled space of vertical farms.Bethany Eldridge, a researcher at the University of Bristol studying root-environment interactions and first author of the study adds: "Given that 80% of agricultural land worldwide is reported to have moderate or severe erosion, the ability to grow crops in a soilless system with minimal fertilizers and pesticides is advantageous because it provides an opportunity to grow crops in areas facing soil erosion or other environmental issues such as algal blooms in local water bodies that may have been driven by traditional, soil-based, agriculture."Lilly Manzoni, Head of Research and Development at LettUs Grow and one the authors of the study says, "This paper is unique because it is broader than a typical plant research paper, it combines the expertise of engineers, aerosol scientists, plant biologists and horticulturalists. The wonderful thing about controlled environment agriculture and aeroponics is that it is truly interdisciplinary."The study Getting to the Roots of Aeroponic Indoor Farming appears in the
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Agriculture & Food
| 2,020 |
July 13, 2020
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https://www.sciencedaily.com/releases/2020/07/200713104339.htm
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Parasite infestations revealed by tiny chicken backpacks
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Blood-feeding livestock mites can be detected with wearable sensor technology nicknamed "Fitbits for chickens."
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To help farmers detect mite infestations, a team of entomologists, computer scientists, and biologists led by UC Riverside entomologist Amy Murillo has created a new insect detection system. The team's work is detailed in the journal In recent years, concern for the well-being of livestock has given rise to more farms where poultry are allowed to roam. Though this freedom improves the quality of chickens' lives, free-range chickens are still subject to insect infestations."The trend in egg sales is 'cage free,' but that doesn't necessarily mean the chickens are insect free," Murillo said.Of particular concern to scientists is the northern fowl mite, which Murillo said feeds on chicken blood and lives on hens in feathers surrounding "the butt area of the chicken."In addition to the economic consequences of infected hens laying fewer eggs, mites can make the chickens sick and cause lesions to develop on their skin."Fowl mites are very unpleasant for the birds being fed upon and cause an itchy immune response," Murillo said.To devise their detection system, Murillo's team first identified three key chicken pastimes closely linked to chickens' well-being: pecking, preening, and dustbathing. The team hypothesized they would see a big increase in preening and dustbathing among infected chickens because these activities keep feathers clean.The team placed motion sensors into tiny backpacks the chickens could wear without discomfort. The next challenge was translating data from these sensors into algorithms that could be detected as behaviors.Alireza Abdoli, a doctoral student in computer science at UCR, explained that quantifying fowl behavior isn't as simple as working with human behaviors like walking, because it isn't as regular.In order to train a computer to recognize chicken behaviors, Abdoli had to take an unusual approach. He created an algorithm, or set of instructions, for the computer that considers the shape that the backpack sensor data makes on a graph, as well as features of the data such as mean and max."Most algorithms use either shape or features, but not both," Abdoli said. "Our approach is exciting because it increases the accuracy of the data so much and is key to making good decisions about the chickens' health."Traditional animal behavior studies have had to rely on video or visual observations, which can be both time consuming and prone to errors. Murillo did some flock observations at the beginning of the project to make sure the computer's conclusions about behaviors were accurate. Once they were certain, observations were no longer necessary, and the computer could take over.Not only does this new approach increase the reliability of scientists' observations, it also increases the number of animals and length of time they can be tracked.The flock in this study did suffer from a mite infestation, which the team related to an increase in cleaning behaviors. Once the birds were treated and healed, the data showed preening and dust baths went back to normal levels.Far more than farm fashion, these "Fitbits for chickens" offer valuable information for livestock farmers."These results could let farmers know it's time to examine their birds for parasites," Murillo said. "And the tools we developed can also be used examine the effects of any change in a bird's environment or diet."
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Agriculture & Food
| 2,020 |
July 9, 2020
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https://www.sciencedaily.com/releases/2020/07/200709210504.htm
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Study reveals scale of habitat loss for endangered birds
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A new study warns that the last remaining habitat for several endangered bird species in Europe could reduce by up to 50 per cent in the next century as farmers convert land to more profitable crops and meet increased demand for products such as olive oil and wine.
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Low intensive agricultural practices created semi-natural agro-steppes that hold important populations of great bustards, little bustards, lesser kestrels, rollers and other at risk bird species. In the early 2000s several of these sites were designated as Special Protection Areas (SPAs) for bird conservation and are part of the EU Natura 2000 network of priority areas for conservation.Researchers at the University of East Anglia (UEA) and University of Lisbon assessed the effectiveness of Natura 2000, the world's largest protected area network, at conserving Western Europe's agro-steppes over a 10-year period. The regions in Iberia studied hold approximately a third -- or 14-15,000 -- of the world's population of great bustards, Otis tarda.Agro-steppes are characterised by the cultivation of cereal in a low-intensity rotating system. These low yield farmlands are being converted predominately to permanent and irrigated crops, which dramatically changes the open landscapes that provide resources for important bird populations.Traditional olive groves and vineyards are occasionally used for feeding or resting by great bustards, little bustards or sandgrouses, but the modern versions of these and other permanent crops are intensively managed and inadequate for such birds.If the current market pressure on agro-steppe habitat conversion is maintained, it may decline 20 per cent by 2050 and 40 per cent by 2110. Declines will be more severe if the demand for products derived from permanent or irrigated crops continues to increase. For example, with high demand for Mediterranean products such as olive oil and wine, agro-steppes within SPAs may soon be the only areas left to be converted.The findings, published in the journal João Gameiro, a PhD student at the Centre for Ecology, Evolution and Environmental Changes (cE3c), University of Lisbon, led the study, which used aerial imagery to classify how agro-steppes have changed from 2004 to 2015. He said: "The Natura 2000 network is the centrepiece of Europe's biodiversity conservation strategy and has enabled an important comeback of a very diverse range of mammals and birds, including the great bustard and the lesser kestrel."However, it is important to consider why losses occurred even within these protected sites. This will compromise the positive outcomes of past conservation efforts and, at the current rate of habitat conversion, agro-steppes could be reduced to 50 per cent of the present area during the next century."The researchers suggest that weak enforcement of the restrictions imposed by the protected area network, insufficient incentives to warrant the co-operation of farmers, and short-term habitat conservation measures, are likely to affect the success of Natura 2000 sites in the protection of other key habitats throughout Europe, especially in human-dominated landscapes where conservation may often compete with economic activities.PhD co-supervisor Dr Aldina Franco, of UEA's School of Environmental Sciences and Centre for Ecology, Evolution and Conservation, said: "Although ecological restoration has become a priority and a reality in Europe, we are still losing important priority habitats for conservation. This study highlights crucial insufficiencies that need to be addressed to realize the full potential of the network, halt biodiversity loss, and meet the goals of a new global biodiversity framework soon to be defined by the UN Convention on Biological Diversity."It is crucial to develop new agricultural methods and improve agricultural productivity to feed an increasing human population. This should reduce pressure on the conversion of natural habitats into new agricultural areas."However, at the same time, we also need to allocate large areas of land to less intensive agricultural methods where human activities are compatible with the persistence of wider countryside species and deliver a variety of ecosystem services and resilience. Finding this balance is a challenge for humanity."The researchers also warn that the greater farmland conversions outside protected sites may transform the remaining agro-steppes into isolated 'islands' restricted to protected areas, with low population connectivity. Maintaining connectivity is important for population viability and to facilitate dispersal, which is particularly significant in light of climate change.They add that in agro-steppes and other human-dominated landscapes, farmers may have to diversify their economic activities to remain economically viable, a process that should be funded by agro-environment financial methods.
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Agriculture & Food
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July 9, 2020
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https://www.sciencedaily.com/releases/2020/07/200709135613.htm
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Aquaculture's role in nutrition in the COVID-19 era
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Aquaculture, the relatively young but fast-growing industry of farming of fish and other marine life, now produces around half of all seafood consumed by humans. A new paper from American University published today examines the economics of an aquaculture industry of the future that is simultaneously environmentally sustainable and nutritious for the nearly 1 billion people worldwide who depend on it for health and livelihoods.
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Of the scenarios the paper discusses, included are two approaches that illustrate what aquaculture might look like if nations refocus inward for food and nutrition security in the COVID-19 era."Seafood is essential to meeting global food and nutrition security goals," said Jessica Gephart, the paper's primary author and an assistant professor of environmental science at American University. "Under what circumstances, and with what policies, can we maximize aquaculture for its nutrition benefits and sustainability for all who rely on seafood?"This is a challenging question to answer, especially in the COVID-19 era. As the pandemic is still unfolding, the full scope of long-term damage to food systems is unknown, the paper notes. Yet, the aquaculture industry is suffering major setbacks, as some exports are being halted, workers are being laid off, demand has dramatically decreased, production units are incurring large losses and some countries are reconsidering their reliance on foreign seafood. The authors note that such setbacks "can be particularly long-lasting for a budding sector, with many young farms that potentially lack the capital to weather the storm and the political clout to secure sufficient recovery aid."The demand for seafood is expected to increase significantly by 2050, the paper notes, if historical trends in income and population growth, urbanization, and diets are maintained. This has prompted researchers to contemplate the future role of aquaculture in meeting demand and supporting nutrition needs. "Nutrition sensitivity" refers to the multiple benefits derived from diverse foods, including improving nutrition, valuing the social significance of food, and supporting livelihoods.For aquaculture, this means a food system that supports public health through production of diverse seafood, provides multiple, rich sources of essential nutrients, and supports equitable access to nutritious, safe, and culturally acceptable diets that meet food preferences for all populations, without compromising ecosystem functions, other food systems, and livelihoods.The paper describes and discusses four possible scenarios for the future of the growth of aquaculture, with the first two outlining what an inward approach might look like. Elements of each of these scenarios exist in current production systems from around the world:Growth-first, nationalistic approach. In this scenario, countries throughout the world turn inward for economic growth and focus on supporting national industries to meet seafood demand. Overall, diversity of seafood available in each country generally declines. Countries with mature aquaculture sectors that already supply a diversity of production technologies, species and product types will continue to meet some nutritional needs, but for a narrower range of consumers and at increased cost, and to a more limited extent.Sustainable growth, localized approach. In this approach, countries throughout the world adopt sustainable local food production approaches focused on small-holder production. While some traditional production systems are highly productive, in general, global aquaculture production grows at a relatively slow rate -- if at all -- and total production is relatively low. Countries that have retained a cultural history of developing small-scale aquaculture will see an increase in these production systems, supported by government-backed schemes and extension services. When production is at the household scale, women are more likely to play a key role, increasing the likelihood that nutritional benefits flow directly to the most vulnerable.Sustainable growth, globalized world. The world fully embraces the application of sustainable development principles, taking advantage of the benefits of globalized food systems while strengthening environmental governance. Global competition and high levels of technology transfer lead to relatively high global inland and marine seafood production. Favoring production of seafood in line with local environmental contexts, this world leads to moderate global species diversity. High global seafood production and low trade barriers enable low seafood prices, improving seafood access in urban areas and areas with transportation infrastructure connections and access to electricity for refrigeration.Growth first, globalized world. In this scenario, the world moves toward further economic globalization and encourages boundless economic growth. Through genetic selection and modification, as well as technological innovations, the aquaculture industry develops intensive production systems with limited environmental regulation. Production systems rely on globalized supply chains, sourcing feed ingredients internationally, and taking advantage of low labor costs for processing. Through competition, massive production of only a few species results, which are highly traded and spread rapidly (akin to the dominance of four species in the meat market, led by chicken). Targeted policy interventions would be necessary to help nutritionally vulnerable populations."Scenarios for global aquaculture and its role in human nutrition," is published in
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Agriculture & Food
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July 9, 2020
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https://www.sciencedaily.com/releases/2020/07/200709135611.htm
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Native bees also facing novel pandemic
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Move over, murder hornets. There's a new bee killer in town.
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CU Boulder researchers have found there is growing evidence that another "pandemic," as they call it, has been infecting bees around the world for the past two decades and is spreading: a fungal pathogen known as Nosema.Yet while it's been documented across Europe, Canada and even in Kenya, this infection has almost exclusively been recorded in the European honeybee, the recognizable commercial pollinator. Their findings, published in Plos Pathogens, reveal that almost nothing is known about the impact of this pathogen on native, solitary bees, which make up the majority of the approximately 20,000 bee species on the planet."More work needs to be done to understand Nosema infections in native bee species and the potential consequences to native ecosystems, if native bees suffer a similar fate as honeybees when infected," said Arthur Grupe II, lead author and postdoctoral researcher in the Department of Ecology and Evolutionary Biology.Not only are native bees incredibly important as pollinators in their local ecosystems, as honeybees are not generally found in these places, but they also contribute to pollination of agricultural crops."One out of every three bites of the food we eat is due to a pollinator," said Grupe.Bee populations, and specifically honeybee hives, around the world have been declining in the past two decades due to colony collapse disorder. While there is no singular cause behind this phenomenon, bees and their colonies' health are affected by what's known as the four P's: pests, pathogens, poor nutrition and pesticides.Nosema is a fungal pathogen, a type of Microsporidia, or spore-forming single-celled parasite.It survives by infecting the guts of bees, where it germinates, infects the host's cell, reproduces, and ruptures the host cell to release its spores. While being passed through the digestive tract, these spores can infect other cells in the bee's body, sickening the bee and contaminating flowers, pollen, and hives along the way. Some strains of Nosema even lower sperm count and mutilate the male genitalia of bumblebees, reducing their reproductive success.Different strains, mainly Nosema apis and Nosema ceranae, are now also appearing in new places, with some strains, specifically N. ceranae, causing year-round infections in hives where previously the bees could fight it off seasonally.So far only Nosema bombi, which infects bumblebees, has been documented in Colorado. However, the more detrimental N. ceranae is probably not far behind, according to Grupe.A few treatments exist, including plant extracts, breeding methods for resistance and microbial supplements. But most research in native bee populations has been limited to DNA-based methods which test for the pathogen in a bee, rather than looking more holistically at how it effects the bee and the broader population.The study authors say it's crucial for scientists to better understand how these Nosema strains are traveling the globe and affecting native, solitary bees, as they could lead to further bee pandemics and contribute to colony collapse.Some flowers, like the snapdragon (Penstemon), can only be pollinated by a bee or insect with the right size and weight, triggering the flower to open as the bee lands on it. If that type of bee is wiped out by an infection, that plant could also disappear -- and with it, other animals that ate its fruit or leaves.Flowers are also almost exclusively where solitary bees -- the majority of all bee species -- meet their mates, since otherwise females nest alone in the ground or in structures built from plant materials. If these flowers die off, so too do the places where bees find their reproductive partners.Another major threat for native bees is pathogen spillover, when infected bees from commercial hives leave the fungus on flowers and native bees pick it up. These native bees, having never encountered this pathogen before, could be much more susceptible to its negative effects.The same thing could happen in reverse: If a novel strain of Nosema develops in native bees, that more aggressive strain could then find its way back into commercial honeybee populations -- who wouldn't have resistance to that particular version of it.Without knowing how Nosema is affecting native, solitary bees, a whole pandemic and its ecological consequences could be going on unnoticed."We know so little about the biology of what's happening," said Alisha Quandt, co-author and assistant professor of ecology and evolutionary biology. "That's one of the reasons why we think it's so important for people to start doing this kind of surveillance work, going out there and sampling more native bees."
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Agriculture & Food
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July 9, 2020
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https://www.sciencedaily.com/releases/2020/07/200709113515.htm
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Born to be a cannibal: Genes for feeding behavior in mandarin fish identified
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Some mandarin fish species (Sinipercidae) are pure fish-eaters, which feed exclusively on living juvenile fish -- also of their own species. A research team led by the Chinese Huazhong Agricultural University (HZAU) and the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB) has described the genome of four mandarin fish species and thus also identified genes for cannibalistic eating behaviour. Knowledge of the connections between the genome and feeding behaviour is of interest for sustainable aquaculture.
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Most fish larvae feed on easily digestible, small zooplankton. Not so some species of mandarin fish. These are pure "fish-eaters" already after hatching and feed on young fish of other fish species and on conspecifics. This cannibalism leads to a high mortality rate of juvenile fish and to economic losses in aquaculture.The researchers compared the genome sequences of different species of mandarin fish and were thus able to trace the evolution of 20,000 genes over a period of 65 million years. They were able to link many genes with species-specific characteristics. "For 32 of these evolving genes, we were able to experimentally demonstrate different gene expression in mandarin fish species that are common to other food and in pure fish-eating species," explains Ling Li, one of the first authors of the study and guest scientist from HZAU at the IGB.Mandarin fish are aggressive predators. During the complex genome analysis, the researchers identified so-called candidate genes that are associated with particularly high aggression and affect behaviour. "Our genome analyses show the evolutionary development of mandarin fish. They have adapted rapidly to changing environmental conditions, especially with regard to their feeding behaviour. Today, some mandarin fish species are more aggressive predators than others due to their genetic predisposition," says Prof. Xu-Fang Liang from HZAU."Research on the relationship between the genetic code and feeding behaviour is an important basis for the sustainable aquaculture of these fish. In future, fish farmers will be able to use marker based selection to choose fish for breeding where the genome indicates less predatory behavior -- and thus reduce losses," summarises Dr. Heiner Kuhl, leading bioinformatician of the project from the IGB.The reference genome for Siniperca chuatsi is one of the highest quality fish genomes to date. It was analysed using third-generation sequencing techniques and has very high sequence continuity and almost complete reconstruction of the 24 chromosomes. The high-quality reference genome enabled the cost-efficient sequencing of three other species from the Sinipercidae family by means of comparative genomics. This approach to create genome sequences for entire taxonomic families of organisms could serve as a blueprint for large-scale genomic projects.
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Agriculture & Food
| 2,020 |
July 9, 2020
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https://www.sciencedaily.com/releases/2020/07/200709085306.htm
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Gall fly outmaneuvers host plant in game of 'Spy vs Spy'
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Over time goldenrod plants and the gall flies that feed on them have been one-upping each other in an ongoing competition for survival. Now, a team of researchers has discovered that by detecting the plants' chemical defenses, the insects may have taken the lead.
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According to John Tooker, professor of entomology, this complex scenario begins when a female gall fly (Eurosta solidaginis) lays its eggs in the leaf bud of a goldenrod plant (Solidago altissima). This action forces the plant to produce a tumor-like growth, called a gall. This gall, he said, provides the fly larvae with a source of nutrition and safety from predators and the environment but decreases the plants' ability to reproduce."Our previous research showed that goldenrod plants have evolved to 'eavesdrop' on the sexual communications of their gall fly herbivores -- specifically, the sex pheromones used by males to attract females," he said. "Our new research, suggests that the plants respond to this 'intelligence' by strengthening, also known as 'priming,' chemical defenses to prevent females from laying eggs and inducing gall formation."Eric Yip, postdoctoral scholar in the Department of Entomology, Penn State, explained that this plant-insect dynamic is similar to the reversals of fortune that occur in the "Spy vs. Spy" comic strip, only the characters are a plant and an insect rather than a pair of cartoon drawings.To investigate the effects of priming, the researchers in their new study exposed almost 300 goldenrod plants comprising 11 genetic types -- or genotypes -- to male flies that varied in age, from one to four weeks old, as well as a control in which the plants were not exposed to flies. Next, the team allowed already-mated females to access the plants, and they counted the number of times a female inserted her ovipositor -- egg-laying device -- into the flower buds as a measure of her preference for particular plants. The team then tracked gall formation.The findings appear today (July 9) in the The scientists found that although priming led to reduced gall formation overall, its effects varied by the age of the male flies used for priming. Priming by younger males resulted in significantly fewer galls, while priming by older males yielded more galls."The female flies in our study appeared to 'know' -- likely via some sort of code breaking that we have yet to understand -- that their offspring would be most successful on plants that had been primed to a lesser degree by the older males.The effects of priming also differed by plant genotype."One genotype became completely resistant to galling after priming, but another became more vulnerable when exposed to older male flies," said Yip. "So, the plant evolved to protect itself against the fly, and subsequently the fly, at least on some plant genotypes, has evolved to make galls more likely."The team plans to next investigate how flies, through their avoidance of primed plants, may be asserting further selective pressure on the evolution of this defense."Ultimately," Tooker said, "the findings could have practical applications in agriculture, perhaps enabling us to enhance crop plants' defenses against pests without the use of toxic pesticides."
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Agriculture & Food
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July 7, 2020
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https://www.sciencedaily.com/releases/2020/07/200707120651.htm
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Antioxidants in corn line could aid human IBD protection, therapy
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Flavonoids from a specific line of corn act as anti-inflammatory agents in the guts of mice with an inflammatory-bowel-disease-like condition, according to a team of researchers who said flavonoid-rich corn should be studied to determine its potential to provide a protective effect on human health.
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The researchers bred a novel line of corn at Penn State's Russell E. Larson Agricultural Research Center to produce compounds called flavan-4-ols. The team then conducted an experiment with mice to judge the effect of those powerful antioxidant compounds on induced inflammation of the colon."In this study, we utilized two corn lines -- one containing flavan-4-ols and one lacking flavan-4-ols -- to investigate the anti-inflammatory property of that flavonoid," said Surinder Chopra, professor of maize genetics in the College of Agricultural Sciences, Penn State. "They are near isogenic lines, meaning that their genetic makeups are identical except for a few specific genetic loci that are responsible for generation of the flavonoids."According to the researchers, inflammatory bowel disease, often referred to as IBD, is a chronic intestinal inflammatory condition that awaits safe and effective preventive strategies. Naturally occurring flavonoid compounds are promising therapeutic candidates against IBD due to their great antioxidant potential and ability to reduce inflammation and leaky gut syndrome.A growing number of epidemiological studies show that diets rich in fruits and vegetables, which contain a significant amount of flavonoids, have been associated with reduced risk of hypertension, cardiovascular disease, type 2 diabetes and other chronic diseases such as inflammatory bowel disease. In addition to their anti-inflammatory properties, naturally occurring flavonoids are safer than standard drugs.In the study, researchers obtained seeds for an inbred corn line from the National Seed Storage Laboratory at Fort Collins, Colorado, and for a corn genetic stock containing genes required for the flavonoid pathway. After back-crossing the plants, the resulting hybrid possesses a higher antioxidant capacity than conventional lines -- a promising trait that could be introduced into elite cultivars to increase dietary benefits, according to Chopra.Mice in the study with the induced-IBD syndrome were divided into four groups. One group was fed a control, or standard, diet. The second and third groups' diets were supplemented with corn containing flavan-4-ols at 15% and 25%. The fourth group was fed a diet supplemented with a genetically related corn that did not contain the flavonoids.In findings recently published in The idea that flavonoids coming from grains may promote human health is a new one, noted Lavanya Reddivari, assistant professor of food science at Purdue University, who helped guide the study. She and Chopra began collaborating on research related to antioxidant compounds in crop plants about five years ago when she was a faculty member at Penn State."Most of the epidemiological studies focus on flavonoid-enriched fruits, especially berries," she said. "However, grains contain a high concentration of bound flavonoids that are thought to exert better antioxidant activity and prolonged presence in systemic circulation, compared to free-form flavonoids, due to their slower and continuous release during digestion and microbial fermentation. These results suggest the feasibility of a human intervention study with flavonoid-rich corn to investigate its protective effects."
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Agriculture & Food
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July 7, 2020
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https://www.sciencedaily.com/releases/2020/07/200707113331.htm
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Agriculture - a climate villain? Maybe not!
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The UN's Intergovernmental Panel on Climate Change (IPCC) claims that agriculture is one of the main sources of greenhouse gases, and is thus by many observers considered as a climate villain. This conclusion, however, is based on a paradigm that can be questioned, writes Per Frankelius, Linkoping University, in an article in
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The fundamental process in agriculture is large-scale photosynthesis, in which carbon dioxide is captured by crops and at the same time oxygen is produced. A fraction of the carbon is bound in the plant roots, while most of it is bound in the form of carbohydrates that are harvested and used in other sectors of society. This involves various form of cereal, oilseed crops, vegetables and grassland."The fact that the carbon is bound in the crops, which at the same time produce oxygen, just as growing forest does, is a positive effect that is not included in the IPCC calculations. These only consider the greenhouse gases that have a negative impact on the climate. This is also the case in The Greenhouse Gas Protocol, which is a well established standard for calculating the emission of greenhouse gases," says Per Frankelius, associate professor in business administration at Linköping University, who has recently written an article in the "This view is based on a paradigm that has essentially never been questioned. Politicians and decision-makers must understand the complete range of the climate impact of agriculture, otherwise there is a risk that many decisions that influence long-term sustainability in a negative manner will be taken," says Per Frankelius.The justification that crops are not included as a positive factor is probably that carbon dioxide is formed in the next step along the chain, when the crops are consumed by humans. "But that takes place in another sector: it's not part of agriculture," Per Frankelius points out.Per Frankelius gives an example calculation in the article in Many different crops are cultivated as agricultural products, and all of them perform photosynthesis. One common crop is cereals, such as wheat, and in 2019, global production of cereals was 2.7 billion tonnes. This corresponds to approximately 1 billion tonnes of carbon, which in turn corresponds to 3.8 billion tonnes of carbon dioxide. The figure would be significantly higher if we included other crops such as oilseed crops and sugar beet."The total agricultural production has been estimated to be 9200 million tons by FAOSTAT. Different crops have different water content, but a good guess is that the total production corresponds to approximately 9100 million tonnes of carbon dioxide," adds Per Frankelius.Agriculture produces also grasslands and grazing that bind carbon, and a further 2.7 billion tonnes of carbon is bound in the soil."So is agriculture one of the world's largest climate villains, or does the sector actually have a positive impact on climate?" asks Per Frankelius.He does not question the fact that agriculture also produces a significant amount of negative greenhouse gases, and it is important to reduce this in a sustainable manner.Per Frankelius, who is also process manager at Agtech 2030, an innovation platform at Linköping University, presents in the article no less than seven concrete measures that can both advance the sector and reduce emissions. The measures range from ensuring that fields are green throughout the year to the marketing of animal ecosystem services, the use of fossil-free mineral-based fertilisers, the spread of biochar, replacing diesel by fossil-free biodiesel, electricity, fuel cells or even steam to power engines, planting trees in rows along the edges of fields and placing solar panels there to follow the sun with a recently patented technology, and various ways to reduce soil compaction. He refers to concrete examples in all cases.The conclusions Per Frankelius draws are unambiguous: in order to achieve long-term sustainability, all aspects of global agriculture must be developed, not wound down or given less advantageous economic conditions. One key to success is innovation.
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Agriculture & Food
| 2,020 |
July 7, 2020
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https://www.sciencedaily.com/releases/2020/07/200707084008.htm
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Nutrients in microalgae: An environmentally friendly alternative to fish
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Microalgae could provide an alternative source of healthy omega-3 fatty acids for humans while also being more environmentally friendly to produce than popular fish species. This is the result of a new study by scientists from Martin Luther University Halle-Wittenberg (MLU). The study was recently published in the
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Microalgae have been the focus of several decades of research -- initially as a raw material for alternative fuels, but more recently as a source of nutrients in the human diet. They are mainly produced in open ponds in Asia; however, these ponds are at risk of potential contamination. Also, some species of algae are easier to cultivate in closed systems, so-called photobioreactors. "We wanted to figure out whether microalgae produced in photobioreactors in Germany could provide a more environmentally friendly source of essential nutrients than fish," says Susann Schade from the Institute of Agricultural and Nutritional Sciences at MLU. Up to now, photobioreactors had usually only been compared to pond cultivation and they often scored worse due to their higher environmental impacts. "However, little research has been done on the precise extent of the environmental impacts of algae produced for human consumption, especially under climatic conditions such as those found in Germany," adds Schade.For their study, the researchers developed a model to determine location-specific environmental impacts. "One of the things we did was to compare the carbon footprint of nutrients from microalgae and fish. We also analysed how much both food sources increase the acidification and eutrophication in water bodies," explains Dr Toni Meier, head of the Innovation Office nutriCARD at MLU. The researchers were able to show that microalgae farming has a similar impact on the environment as fish production. "However, if we compare the environmental effects in relation to the amount of omega-3 fatty acids produced, fish from aquaculture comes off far worse," says Schade. One advantage of algae cultivation is its low land consumption; even infertile soils can be used. In contrast, both open ponds and the cultivation of feed for aquaculture require very large areas of land. In particular, fish species that are popular in Germany, such as salmon and pangasius, are primarily produced through aquaculture and therefore put the environment under a considerable amount of pressure. However, even fishing wild Alaska pollack had poorer values than microalgae for all environmental indicators."Microalgae should not and cannot completely replace fish as a food source. But if microalgae could be established as a common food, it would be another excellent environmentally friendly source of long-chain omega-3 fatty acids," explains Meier. Several algae are already used as a food supplement in powder or tablet form and as an additive to foods such as pasta or cereals. It would be a way to reduce the current gap in the global supply of omega-3 fatty acids. At the same time, it would provide considerable relief to the world's oceans.
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Agriculture & Food
| 2,020 |
July 6, 2020
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https://www.sciencedaily.com/releases/2020/07/200706152653.htm
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Group genomics drive aggression in honey bees
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Researchers often study the genomes of individual organisms to try to tease out the relationship between genes and behavior. A new study of Africanized honey bees reveals, however, that the genetic inheritance of individual bees has little influence on their propensity for aggression. Instead, the genomic traits of the hive as a whole are strongly associated with how fiercely its soldiers attack.
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The findings are reported in the "We've always thought that the most significant aspects of an organism's behavior are driven, at least in part, by its own genetic endowment and not the genomics of its society," said Matthew Hudson, a University of Illinois at Urbana-Champaign professor of bioinformatics who led the research with Gene Robinson, an entomology professor and the director of the Carl R. Woese Institute for Genomic Biology at the U. of I. "This is a signal that there may be more to genetics as a whole than we've been thinking about."The researchers focused on a unique population of gentle Africanized honey bees in Puerto Rico, which have evolved to become more docile than Africanized bees anywhere else in the world."We wanted to know which parts of the genome are responsible for gentle behavior versus aggressive behavior," Hudson said. "And because these are Africanized bees but they're also gentle, they are an ideal population to study. There's quite a bit of variation in aggression among them."Africanized bees are hardier and more resistant to disease than their European predecessors on the island, so scientists are eager to learn more about the genetic underpinnings of the Puerto Rican bees' gentle nature.When a honey bee hive is disturbed, guard bees emit a chemical signal that spurs soldier bees into action. The response depends on the nature of the threat and the aggressiveness of the hive. Whether the soldiers sting their target is another measure of aggression, as soldiers that sting will die as a result.In general, foragers do little to defend the hive.The researchers compared the genomes of soldier and forager bees from each of nine honey bee colonies in Puerto Rico. They also tested how aggressively the soldier bees responded to an assault on the hive.To their surprise, the scientists found no genome-sequence differences between the soldiers and foragers that consistently explained the different responses.But when the researchers conducted a genomewide association study comparing the the most-aggressive and least-aggressive hives, they saw a strong correlation between hive genomics and aggression. The analyses revealed that one region of the genome appeared to play a central role in the hives' relative gentleness or aggression."Mostly these bees' genomes look like Africanized bees," Hudson said. "But there was one chunk that looked very European. And the frequency of that European chunk in the hive seems to dictate how gentle that hive is going to be to a large extent."What that tells us is that the individual genetic makeup of the bee doesn't have a strong influence on how aggressive it is," he said. "But the genetic makeup of the society that the bees live in -- the colony -- has a very strong impact on how aggressive the bees in that colony are.""Many behavioral traits in animals and humans are known to be strongly affected by inherited differences in genome sequence, but for many behaviors, how an individual acts also is influenced by how others around it are acting -- nature and nurture, respectively," Robinson said. "We now see that in the beehive, nurture can also have a strong genomic signature."Such behavioral genomic influences may be particularly pronounced in honey bees, which live in an extraordinarily cooperative society where each individual has a defined social and functional role, he said.Hudson also is a professor of crop sciences at Illinois.
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Agriculture & Food
| 2,020 |
July 6, 2020
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https://www.sciencedaily.com/releases/2020/07/200706145435.htm
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Newly discovered pathogen in NY apples causes bitter rot disease
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In a study of New York state apple orchards, Cornell University plant pathologists have identified a new fungal pathogen that causes bitter rot disease in apples. In addition, a second related fungus known to cause rot disease in other fruits was found for the first time in apples.
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"We were shocked by what we found, just dumbfounded," said Srdjan Acimovic, a senior extension associate at the Hudson Valley Research Laboratory (part of Cornell AgriTech) and the paper's senior author. "We found these two species, one that has never been described before and one that has been described before but never on this host."Both pathogens belong to the genus If protective practices are not applied in a timely manner, apple losses from bitter rot in New York state can average up to 25% per year, with reports of some organic farms losing up to 100% of their crop. Bitter rot also accounts for up to 5% additional loss of marketable fruit in storage post-harvest.This damage is costly for farmers; the farm gate value for New York apples was roughly $260 million in 2018, according to U.S. Department of Agriculture statistics.The dominant species found in the apples was "When we know which species are dominant in our area, we know how environmental conditions will affect them and which control method is best in an orchard," said study first author Fatemeh Khodadadi, a postdoctoral researcher in Acimovic's lab.In the future, the researchers plan to work with other plant pathologists and apple breeders to identify possible genes that confer natural resistance to
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Agriculture & Food
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July 6, 2020
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https://www.sciencedaily.com/releases/2020/07/200706113948.htm
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Coconut confusion reveals consumer conundrum
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Coconut oil production may be more damaging to the environment than palm oil, researchers say.
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The issue of tropical forests being cut down for palm oil production is widely known, but the new study says coconut oil threatens more species per litre produced than palm or other vegetable oils.The researchers use this example to highlight the difficulties of "conscientious consumption."They say consumers lack objective guidance on the environmental impacts of crop production, undermining their ability to make informed decisions."The outcome of our study came as a surprise," said lead author Erik Meijaard, of Borneo Futures in Brunei Darussalam."Many consumers in the West think of coconut products as both healthy and their production relatively harmless for the environment."As it turns out, we need to think again about the impacts of coconut."Co-author Dr Jesse F. Abrams, of the Global Systems Institute and the Institute for Data Science and Artificial Intelligence, both at the University of Exeter, added: "Consumers, especially those striving to be more responsible in their consumption, rely heavily on information that they receive from the media, which is often supplied by those with vested interests."When making decisions about what we buy, we need to be aware of our cultural biases and examine the problem from a lens that is not only based on Western perspectives to avoid dangerous double standards."According to the study, production of coconut oil affects 20 threatened species (including plants and animals) per million litres of oil produced. This is higher than other oil-producing crops, such as palm (3.8 species per million litres), olive (4.1) and soybean (1.3).The study shows that the main reason for the high number of species affected by coconut is that the crop is mostly grown on tropical islands with rich diversity and many unique species.Impact on threatened species is usually measured by the number of species affected per square hectare of land used -- and by this measure palm's impact is worse than coconut.Coconut cultivation is thought to have contributed to the extinction of a number of island species, including the Marianne white-eye in the Seychelles and the Solomon Islands' Ontong Java flying fox.Species not yet extinct but threatened by coconut production include the Balabac mouse-deer, which lives on three Philippine islands, and the Sangihe tarsier, a primate living on the Indonesian island of Sangihe.The authors, however, emphasise that the objective of the study is not to add coconut to the growing list of products that consumers should avoid.Indeed, they note that olives and other crops raise also raise concerns.Co-author Professor Douglas Sheil, of the Norwegian University of Life Sciences, said: "Consumers need to realise that all our agricultural commodities, and not just tropical crops, have negative environmental impacts."We need to provide consumers with sound information to guide their choices."The researchers argue for new, transparent information to help consumers."Informed consumer choices require measures and standards that are equally applicable to producers in Borneo, Belgium and Barbados," they write."While perfection may be unattainable, improvements over current practices are not."
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Agriculture & Food
| 2,020 |
July 1, 2020
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https://www.sciencedaily.com/releases/2020/07/200701152919.htm
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Treatments tested for invasive pest on allium crops
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Native to Europe but discovered in Pennsylvania in 2015, the Allium leafminer is a fly whose larvae feed on crops in the Allium genus, including onions, garlic and leeks.
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Since its arrival in the U.S., it has spread to New York, Connecticut, Massachusetts, Maryland and New Jersey, and is considered a major agricultural threat. A Cornell University-led team of researchers field-tested 14 active ingredients in insecticides, applied in a variety of methods, to understand the best treatment options.The researchers' findings are described in a study, "Managing Allium Leafminer: An Emerging Pest of Allium Crops in North America," published in the The research team, led by senior author Brian Nault, professor of entomology at Cornell AgriTech and one of the nation's leading Allium leafminer management experts, found that several traditional chemical insecticides worked best against the invasive insect."Problems with the Allium leafminer tend to be worse on organic farms where highly effective management tools -- synthetic insecticides -- are not used," Nault said.The Allium leafminer (Crops with green foliage during either adult leafminer generation are most at risk. In the northeastern U.S., these include chives, scallions and garlic in the spring, and scallions and leeks in the fall. Wild alliums, which cross both generations, can be a reservoir where the insects to grow.Larvae start feeding at the tops of plants and migrate toward the base to pupate. The larvae can destroy vascular tissue, which can lead to bacterial or fungal infections that cause rot.The research team tested various management strategies with onions, leeks and scallions in Pennsylvania and New York in 2018 and 2019. Spraying chemical insecticides (dinotefuran, cyantraniliprole and spinetoram) was the most consistent and effective method, with up to 89% reduction in damage and up to 95% eradication of the insect. Dinotefuran and cyantraniliprole applied through a drip irrigation technique were not effective.Other insecticides (abamectin, acetamiprid, cyromazine, imidacloprid, lambda-cyhalothrin, methomyl and spinosad) also reduced densities of Allium leafminers. Spinosad applied to bare roots, or in plug trays for plant starts, reduced the insect's damage after transplanting by 90%.Though Allium leafminers have not been an issue in onions so far, researchers and farmers are concerned they may become a problem if they gain traction and move west, where onions are a major crop. "This has been a huge concern for the U.S. onion industry," Nault said.
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Agriculture & Food
| 2,020 |
July 1, 2020
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https://www.sciencedaily.com/releases/2020/07/200701134246.htm
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Influence of insect and microalgae feeds on meat quality
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Worldwide there is a growing demand for animal products for human nutrition, despite vegan and vegetarian diets becoming more popular in Western countries. Changing diets necessitate a substantial amount of protein as an input for animal production. Future protein feedstuffs will need to become independent of arable land in order to avoid further land use changes, such as deforestation. The cultivation of insects as well as microalgae are up-and-coming sectors in Germany, as well as globally, to meet protein demands for humans and animals alike. Therefore, a research team at the University of Göttingen investigated whether these alternative protein sources alter typical meat quality. Their results have been published in the
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In a study conducted as a part of the project "Sustainability Transitions in the Food Production," broiler chickens were fattened using feed with the main protein sources being soybean meal, spirulina, or insects. Animal growth, meat quality (especially concerning shelf life), and eating quality were investigated. Their results of laboratory testing and sensory (taste-testing) analyses across 132 birds show that black soldier fly larvae meal and spirulina can be included in poultry feed without negatively impacting quality. Chickens fed with black soldier fly larvae meal produce meat equivalent to the status quo. Chickens fed with spirulina produce meat with a more intensive colour and flavour. "Overall, both prove to be potential soybean meal alternatives in the search for new protein sources for animal feed," as explained by the study lead researcher Dr Brianne Altmann.Microalgae are currently produced globally for biofuel, animal feed, and human consumption; however, they remain much more expensive than soybean meal. Currently in the European Union (EU), insects are only authorized for human consumption and for fish feed; they are likely to be approved for poultry feed in the near future. In the EU, all insects must be produced using certified animal feedstuffs. However, "sustainability necessitates the incorporation of waste products in the production of insects," explains Professor Daniel Mörlein, professor for the Quality of Animal Products.Three groups at the Faculty of Agricultural Sciences, University of Göttingen, are currently examining the foundations for more sustainable and socially-accepted plant and animal-based foods. Product perception as well as consumer acceptance studies are commonly conducted in the faculty's modern sensory laboratory.
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Agriculture & Food
| 2,020 |
July 1, 2020
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https://www.sciencedaily.com/releases/2020/07/200701125502.htm
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Alarming long-term effects of insecticides weaken ant colonies
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Scientists have shown how even low doses of neonicotinoid insecticides, as they may realistically occur in contaminated soils, adversely affect the development of black garden ants (Lasius niger). This study highlights the need to overthink current deployment and management of chemical pest control for more sustainable agriculture.
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"Ants are one of the most important animal groups on our planet. However, they are also affected by the recently observed global declines in abundance and diversity of insects," says Daniel Schläppi of the Institute of Bee Health of the University of Bern, main author of the study. Evidence suggests that pesticides are among the factors responsible for the observed declines. "One problem of these substances is their persistence and the potential to contaminate soils and water, even in areas in which they are not applied," says co-author Gaétan Glauser from the University of Neuchâtel.But so far, no data existed to show how exposure to low concentrations, which do not induce direct mortality, affect ants in the long run. The data, collected at the University of Bern in cooperation with Agroscope and the University of Neuchâtel, clearly demonstrate previously overlooked long-term effects, which are not detectable during the first year of colony development. The results are published in Thiamethoxam has a clear negative impact on the health of ants. Thiamethoxam is a neonicotinoid insecticide used to combat pest insects that threaten our harvest. Unfortunately, there is more and more evidence showing that thiamethoxam and similar agro-chemicals have negative consequences for other beneficial insects, including ants and honey bees."With our study we show that ants, which play a very important roles in our ecosystems and provide valuable ecosystem services such as natural pest control, are negatively affected by neonicotinoids too," says Schläppi.In the present work, colonies of black garden ants were chronically exposed to field realistic concentrations of thiamethoxam over 64 weeks. Colonies were raised in the laboratory from queens that were captured in the field. Before the first overwintering of the colonies no effect of neonicotinoid exposure on colony strength was visible. However, until the second overwintering it became apparent that colonies exposed to thiamethoxam were significantly smaller than control colonies. Because the number of workers is a very important factor for the success of an ant colony, the observed effects are most likely to compromise colony survivorship. Considering the important role of ants in natural ecosystems, our results indicate that neonicotinoids impose a threat to ecosystem functioning."Accumulating long-term impact of neonicotinoids on ants is alarming," says Prof. Peter Neumann of the Institute of Bee Health at the University of Bern. "This is an exemplary study showing how negative effects of an environmental contaminant only become visible after long monitoring, but with potentially far reaching consequences." Therefore, the authors stress the importance to include ants as model organisms and to fully incorporate long-term effects in future risk assessment schemes for more sustainable agriculture.
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Agriculture & Food
| 2,020 |
July 1, 2020
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https://www.sciencedaily.com/releases/2020/07/200701125427.htm
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To listen is to survive: Unravelling how plants process information
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Plants must constantly integrate information on the availability of water and nutrients or about the presence of pathogens to produce fruits and seeds for reproduction, heavily used for human consumption. Given the increasing threat of droughts and the requirements of sustainable plant protection it is important to better understand the molecular mechanisms behind the information processing of plants. So far, different plant hormones were known to trigger molecular signaling pathways that result in developmental transitions like fruit ripening or drought response. While the signaling pathways are well studied, it remained enigmatic how the information exchange between them exactly works.
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A team at the Institute of Network Biology at Helmholtz Zentrum München with the participation of LMU biologists charted the molecular protein network of plants by experimentally testing more than 17 million protein pairs for physical interactions using a next-gen robotics pipeline combined with latest bioinformatics methods. The network of more than 2,000 observed protein interactions was analyzed using bioinformatic mathematical approaches form statistics and graph theory to find the signaling pathways and potential information exchange points. This way the researchers identified hundreds of these points which were not known before.Next, by using genetic tests, they could show that all tested information exchange points between proteins that were thought to function in single signaling pathways, in fact, organize the communication between different pathways. "This was one of the most striking new insights from this study: Most proteins function in multiple signaling pathways. Moreover, in contrast to single-gene analyses, our results revealed the high degree in which different pathways are physically and functionally intertwined. We believe that this is a fundamental principle and we need to pay more attention to it," says Dr. Melina Altmann, first-author of the study.Prof. Pascal Falter-Braun, Director at the Institute of Network Biology and professor at LMU adds: "This insight might open new strategies for biotechnological development or breeding of plants to address the challenges of climate change in farming. We might be able to redirect the information in crops such that the plants require less fertilizer or pesticides or are more resistant against droughts."The finding builds on long-term research at the Institute of Network Biology on understanding molecular networks in plants and humans. The project was funded by the DFG via SFB924 "Molecular mechanisms regulating yield and yield stability in plants" and by an ERC consolidator grant awarded to Prof. Pascal Falter-Braun. For this study, the group collaborated with groups from the School of Life Science at the Technical University of Munich (TUM), colleagues from the Department of Environmental Sciences at the Helmholtz Zentrum München, and the University of Warwick, UK.
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Agriculture & Food
| 2,020 |
June 30, 2020
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https://www.sciencedaily.com/releases/2020/06/200630150414.htm
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Sneaky salmonella finds a backdoor into plants
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As the world wrestles with the coronavirus (COVID-19) pandemic, which arose after the virus jumped from an animal species to the human species, University of Delaware researchers are learning about new ways other pathogens are jumping from plants to people.
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Opportunistic bacteria -- salmonella, listeria and But University of Delaware researchers Harsh Bais and Kali Kniel and their collaborators now have found that wild strains of salmonella can circumvent a plant's immune defense system, getting into the leaves of lettuce by opening up the plant's tiny breathing pores called stomates.The plant shows no symptoms of this invasion and once inside the plant, the pathogens cannot just be washed off.Stomates are little kidney-shaped openings on leaves that open and close naturally and are regulated by circadian rhythm. They open to allow the plant to cool off and breathe. They close when they detect threats from drought or plant bacterial pathogens.Some pathogens can barge into a closed stomate using brute force, Bais said. Fungi can do that, for example. Bacteria don't have the enzymes needed to do that so they look for openings -- in roots or through stomates, he said.Plant bacterial pathogens have found a way to reopen those closed stomates and gain entry to the plant's internal workings, Bais said.But now, in research published by "What's new is how the non-host bacteria are evolving to bypass plant immune response," Bais said. "They are real opportunists. They are absolutely jumping kingdoms....When we see these unusual interactions, that's where it starts to get complex."Opportunities for pathogens arise as plants are bred to increase yield, often at the expense of their own defense systems. Other opportunities arise when a grower plants low-lying crops too close to a livestock field, making contamination easier.Together and separately, Bais and Kniel and their collaborators have been looking at this plant problem from several angles for about five years.They are looking at the "trojan horse" methods bacteria such as salmonella are using to elude plant immune systems and find their way to new human hosts.They are looking at an assortment of irrigation methods that can carry bacteria from waterways, ponds and reclaimed water to the surface and root systems of plants.They are looking at the genetic components that enable pathogens to persist and survive along their passage to a new host.Bais and Kniel have published multiple articles on these threats to the world's food supply and have developed recommendations for increasing plant defenses.Bais' team, for example, developed and patented a beneficial microbe -- UD1022 -- to protect and strengthen plant root systems. That microbe has been licensed by BASF and is incorporated into an increasing variety of applications. Testing done as part of their new publication showed that roots inoculated with UD1022 -- through watering and irrigation -- could provide protection from these opportunistic bacteria.Kniel said she was surprised to see that UD1022 kept some mutants from getting into the plant."There is a lot of hope for biocontrols," she said.Kniel's team and collaborators from the U.S. Department of Agriculture and several other universities in the Mid-Atlantic region, recently published new findings in PLOS One analyzing the pathogenic content of irrigation methods that draw from waterways, ponds and reclaimed water.Those are pre-harvest perils. The post-harvest dangers come more from hygiene practices of workers on the conveyor belts that move these products to market.Many companies run leafy greens through water treated with appropriate sanitizers and may consider ozone or ultraviolet treatments to address surface bacteria. They can't see or treat human pathogens that already have gotten into the leaf."The food industry works tirelessly to make the product as safe as they can," Kniel said. "But even then, we are growing these products outside, so they're accessible to wildlife, wind, dust and water that may transmit microorganisms. It's a tough situation."Nicholas Johnson, a graduate student in Bais' lab, did painstaking work to examine how stomates on spinach and lettuce responded to applications of salmonella, Listeria and He counted these sizes every three hours after the bacteria were applied."He had to sit under a microscope and count the aperture sizes," Bais said. "And he has to be meticulous."He found some troubling results. The salmonella strain was reopening the stomates."Now we have a human pathogen trying to do what plant pathogens do," Bais said. "That is scary."It would be especially scary, Bais said, if it were to occur in a "vertical" farm, where plants are grown in vertical rows hydroponically."These are wonderful systems," Kniel said. "But there needs to be a lot of care within the system to control the water and interactions with people. There has to be a lot of handwashing. I work with a lot of growers to make sure they have 'clean' breaks and are sanitizing properly. When you do that, you have fewer products to recall."But the dangers are real."The industry is working hard on this," Kniel said. "They are some of the most passionate, dedicated people I have ever met. But outbreaks happen.""And if this hits vertical farms, they don't lose a batch," Bais said. "They lose the whole house."The collaboration has drawn on a wide range of expertise, giving researchers insight into many angles of the problem."This project [with Bais] has mutant salmonella strains and that allows us another angle on the molecular biology side," Kniel said. "The individual mutations are important for the salmonella structure and the regulation of stress. We can see the ability of the salmonella to internalize into the plant. When we used mutant strains we saw big differences in the ability to colonize and internalize -- and that's what consumers hear a lot about. You are not able to wash it off."We can also look at which genes or part of the organism might be more responsible for the persistence on the plant -- making it last longer and stronger. That is so important when you think of food safety issues."Among the other questions researchers are asking:Do these bacteria die off more easily when they are in the sun?Does a lot of moisture or humidity allow them to grow?How much do they interact with the plant?The study of irrigation water in the Mid-Atlantic region of the United States was done in collaboration with "Conserve," a Center of Excellence that includes researchers from the U.S. Department of Agriculture and the University of Maryland."We're looking at where growers get their water from and what they are doing to make sure it is microbially safe," she said.Some of the water is reclaimed after it was used to wash other crops. Some comes from waterways and ponds. The team took a series of samples over a two-year period, testing for salmonella, listeria, "Water has been shown in multiple outbreaks to be a potential risk of contamination," Kniel said. "This paper is important because it is identifying the risks of ponds, rivers and reclaimed water as well as discussing what growers could do and how to treat water. A lot of growers are happy to use the technology as long as it is cost-effective and reliable and can be used for fresh produce."
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Agriculture & Food
| 2,020 |
June 30, 2020
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https://www.sciencedaily.com/releases/2020/06/200630125142.htm
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Wild bees depend on the landscape structure
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Sowing strips of wildflowers along conventional cereal fields and the increased density of flowers in organic farming encourage bumblebees as well as solitary wild bees and hoverflies. Bumblebee colonies benefit from flower strips along small fields, but in organic farming, they benefit from large fields. This research was carried out by agroecologists from the University of Göttingen in a comparison of different farming systems and landscape types. The results of the study have been published in the
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Organic farming and flower strips are financially supported by the European Union in order to enhance populations of wild bees and hoverflies, which are major pollinators of most crops and wild plants. The research team selected nine landscapes in the vicinity of Göttingen along a gradient of increasing field size and then analysed the wild bees and hoverflies in each landscape at the edge of an organic wheat field, in a flower strip along conventional wheat, and at the edge of a conventional wheat field without flower strips. The result: most pollinators were found in the flower strips, but organic fields, characterized by more flowering wild plants than conventional fields, were also beneficial. Bumblebee colonies established on the margins of fields as part of the project produced more queens in flower strips when located in landscapes with small conventional fields. In contrast, large areas were particularly advantageous when it came to flower-rich organic fields. Flower strips offer a high local density of pollen and nectar, but organic areas compensate for this by their increased area."The results show that action at both local and landscape level is important to promote wild bees," emphasises Costanza Geppert, first author of the study. The investigations were part of her Master's thesis in the Agroecology Group in the Department of Crop Sciences at the University of Göttingen. "Wild bees and other insects cannot survive in a field simply by making improvements to that field, they depend on the structure of the surrounding landscape," adds Head of Department Professor Teja Tscharntke. "Therefore, future agri-environmental schemes should take more account of the overall landscape structure," adds Dr Péter Batáry who initiated the study.
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Agriculture & Food
| 2,020 |
June 30, 2020
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https://www.sciencedaily.com/releases/2020/06/200630125138.htm
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Plant tissue engineering improves drought and salinity tolerance
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After several years of experimentation, scientists have engineered thale cress, or Arabidopsis thaliana, to behave like a succulent, improving water-use efficiency, salinity tolerance and reducing the effects of drought. The tissue succulence engineering method devised for this small flowering plant can be used in other plants to improve drought and salinity tolerance with the goal of moving this approach into food and bioenergy crops.
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"Water-storing tissue is one of the most successful adaptations in plants that enables them to survive long periods of drought. This anatomical trait will become more important as global temperatures rise, increasing the magnitude and duration of drought events during the 21st century," said University of Nevada, Reno Biochemistry and Molecular Biology Professor John Cushman, co-author of a new scientific paper on plant tissue succulence published in the The work will be combined with another of Cushman's projects: engineering another trait called crassulacean acid metabolism (CAM), a water-conserving mode of photosynthesis that can be applied to plants to improve water-use efficiency."The two adaptations work hand-in-hand," Cushman, of the University's College of Agriculture, Biotechnology & Natural Resources, said. "Our overall goal is to engineer CAM, but in order to do this efficiently we needed to engineer a leaf anatomy that had larger cells to store malic acid that accumulates in the plant at night. An added bonus was that these larger cells also served to store water to overcome drought and to dilute salt and other ions taken up by the plant, making them more salt tolerant."When a plant takes up carbon dioxide, it takes it through its pores on the leaf, called stomata. They open their stomata so carbon dioxide goes in, and then it gets fixed into sugars and all other compounds that support most of life on earth. But, when stomata open, not only does carbon dioxide come in, but also water vapor goes out, and because plants transpire to cool themselves, they lose enormous amounts of water."Cushman's team of scientists created genetically modified A. thaliana with increased cell size resulting in larger plants with increased leaf thickness, more water-storage capacity, and fewer and less open stomatal pores to limit water loss from the leaf due to the overexpression of a gene, known as VvCEB1 to scientists. The gene is involved in the cell expansion phase of berry development in wine grapes.The resulting tissue succulence serves two purposes."Larger cells have larger vacuoles to store malate at night, which serves as the carbon source for carbon dioxide release and refixation, by what's called Rubisco enzyme action, during the day behind closed stomatal pores, thereby limiting photorespiration and water loss" Cushman said. "And, the succulent tissue traps the carbon dioxide that is released during the day from the decarboxylation of malate so that it can be refixed more efficiently by Rubisco.One of the major benefits of VvCEB1 gene overexpression was the observed improvements in whole-plant instantaneous and integrated water-use efficiency, which increased up to 2.6-fold and 2.3-fold, respectively. Water-use efficiency is the ratio of carbon fixed or biomass produced to the rate of transpiration or water loss by the plant. These improvements were correlated with the degree of leaf thickness and tissue succulence, as well as lower stomatal pore density and reduced pore openings."We tried a number of candidate genes, but we only observed this remarkable phenotype with the VvCEB1 gene," Cushman said. "We typically will survey between 10 to 30 independent transgenic lines, and then these are grown for two to three generations before detailed testing."Arabidopsis thaliana is a powerful model for the study of growth and development processes in plants. It is a small weed-like plant that has a short generation time of about six weeks and grows well under laboratory conditions where it produces large amounts of seeds.Engineered tissue succulence is expected to provide an effective strategy for improving water?use efficiency, drought avoidance or attenuation, salinity tolerance and for optimizing performance of CAM.CAM plants are very smart, keeping their stomata closed during the day, and only opening them at night when evapotranspiration is low because it is cooler and the sun is not shining, Cushman explained. The significance of CAM is found in its unique ability to conserve water. Where most plants would take in carbon dioxide during the day, CAM plants do so at night."Essentially, CAM plants are five to six times more water-use efficient, whereas most plants are very water inefficient," he said. "The tissue succulence associated with CAM and other adaptive traits like thicker cuticles and the accumulation of epicuticular waxes, means that they can reduce leaf heating during the day by reflecting some of the light hitting the leaf. Many desert-adapted CAM plants also have a greater ability to tolerate high temperatures."With demand for agricultural products expected to increase by as much as 70% to serve a growing human population, which is predicted to reach about 9.6 billion by 2050, Cushman and his team are pursuing these biotechnology solutions to address potential future food and bioenergy shortages."We plan to move both tissue succulence and CAM engineering into crop plants. This current work is proof-of-concept," Cushman said.The work was funded by the Department of Energy, Office of Science, Genomic Science Program.
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Agriculture & Food
| 2,020 |
June 29, 2020
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https://www.sciencedaily.com/releases/2020/06/200629120143.htm
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Controlling plants with the power of colored light
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University of East Anglia scientists have helped find a way to control different plant processes -- such as when they grow -- using nothing but coloured light.
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The development, published today in the journal The researchers hope that their findings could lead to advances in how plants grow, flower, and adapt to their environment, ultimately allowing increases in crop yields.The research was led by Heinrich Heine University and the Cluster of Excellence on Plant Sciences (CEPLAS) in Düsseldorf, in collaboration with colleagues at the University of Freiburg and UEA.Dr Ben Miller, from UEA's School of Biological Sciences, said: "Our team have been working on optogenetics -- using light to precisely control biological processes -- in plants."Using optogenetics in plants hadn't been possible before because plants naturally respond to light as they grow. Any genetic switches controlled by light would therefore be constantly active."But we have developed a special system which overcomes this problem and allows us to control different cellular processes in plants using light."We can now use a red light to cause gene expression at a precise moment, while an ambient white light can be used as an 'off switch' to reverse the process. This can be repeated any number of times."We can use this system to manipulate physiological responses in plants, for example their immune response, and perhaps their development, growth, hormone signalling and stress responses."The project bridges two hot topics in biology -- optogenetics and synthetic biology.The new tool called PULSE (Plant Usable Light-Switch Elements) is suitable for plants growing under normal day and night cycles.Dr Miller said: "In the future, this research might mean that we can modulate how plants grow, and respond and adapt to their environment, with light cues."For example, we have shown that plant immune responses can be switched on and off using our light-controlled system. If this system was used in crops, we could potentially improve plant defences to pathogens and have an impact by improving yields."Using light to control biological processes is far less invasive and more reversible than using chemicals or drugs, so this new system in plants is a really exciting new tool for us to answer fundamental questions in plant biology."
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Agriculture & Food
| 2,020 |
June 26, 2020
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https://www.sciencedaily.com/releases/2020/06/200626114805.htm
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The millenial pre-colonial cultural influence is evident in the Amazon forest
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Before the arrival of European colonizers, the Amazonian Indigenous peoples cultivated their food -- cassava, corn, pineapple, peppers and squash, among other things. The food of the ancient civilizations of the Amazon also largely consisted of the fruits of palm and Brazilian nut trees. The protection and management of trees across generations have affected the diversity of the rainforest right up until the present time.
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More than ten years ago, large geometric earthworks found in the southwestern parts of the Amazon, called geoglyphs, were reported in the global scientific news. A pre-colonial civilization unknown to scholars that built geometric ceremonial centers and sophisticated road systems. This civilization flourished in the rainforest area 2,000 years ago. The discovery radically altered the prevailing notion of the pristine Amazon rainforest. The research of an interdisciplinary Finnish-Brazilian team continues in the region with the support of the Academy of Finland. Recent findings show that large ancient construction projects not only shaped the landscape, but civilization has also impacted the diverse construction of rainforest.The research team's latest article "Domestication in Motion" has been published in the journal The article also describes how tree domestication was not a linear process in Amazon conditions, as wild forms of plants could also be protected. During the archaeological excavations wild and domesticated forms of peach palm fruit were found, among other plants. On the other hand, especially Brazilian nut trees as well as many palm trees, which are vital for both their fruits and palm kernels, were domesticated in the rainforest area for human consumption. Their fruits are clearly larger than they were 2,000 years ago.A unlinear process of domestication is evident, as both wild and domesticated peach palm trees are still well known by Indigenous peoples in the state of Acre, and the latter have spread to a very large area across the Amazon, says Pirjo Kristiina Virtanen, assistant professor involved in the project.Human impact on the Amazon rainforest stand has been significant, and therefore there is no such thing as virgin rainforest. On the other hand, the study shows that Indigenous peoples of the Amazon have been able to use their environment in a sustainable way by domesticating certain plants while protecting and respecting it. There is no indication that large areas of forest would have been deforested.These new findings argue against the idealistic notion of the pristine Amazon rainforest. At the same time, however, it highlights how Indigenous peoples utilize wild plants while domesticating certain plants for humans' use. The relationship between the peoples of the Amazon and forest has been proved sustainable. It should be explored further and lessons could be learned from this.The authors of the article are from the University of Helsinki. Martti Pärssinen, Professor Emeritus leads the project and Pirjo Kristiina Virtanen, Assistant Professor of Indigenous Studies, has worked with the Indigenous peoples of the region. In addition to them, the authors were Brazilian palm researcher Evandro Ferreira and paleoecologist Alceu Ranzi from the Federal University of Acre. The Finnish Cultural and Academic Institute in Madrid has also contributed to the project. In Brazil the research was authorised by Instituto do Patrimônio Histórico e Artístico Nacional (IPHAN) and Fundação Nacional do Índio (FUNAI).
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Agriculture & Food
| 2,020 |
June 24, 2020
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https://www.sciencedaily.com/releases/2020/06/200624151611.htm
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Crops: Light environment modifications could maximize productivity
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The crops we grow in the field often form dense canopies with many overlapping leaves, such that young "sun leaves" at the top of the canopy are exposed to full sunlight with older "shade leaves" at the bottom. In order to maximize photosynthesis, resource-use efficiency, and yield, sun leaves typically maximize photosynthetic efficiency at high light, while shade leaves maximize efficiency at low light.
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"However, in some of our most important crops, a maladaptation causes a loss of photosynthetic efficiency in leaves at the bottom of the canopy, which limits the plants' ability to photosynthesize and produce yields," said Charles Pignon, a former postdoctoral researcher at the University of Illinois. "In order to address this problem, it's important to know whether this is caused by leaves being older or exposed to a different light environment at the bottom of the canopy."This question was answered in a recent study published in This work was conducted through the Illinois Summer Fellows (ISF) program. Launched in 2018, ISF allows undergraduate students to conduct plant science research alongside highly skilled scientists at Illinois. 2018 Fellows Robert Collison and Emma Raven worked with Pignon and Stephen Long, the Stanley O. Ikenberry Chair Professor of Plant Biology and Crop Sciences at Illinois, to confirm and better understand results from previous studies for Water Efficient Sorghum Technologies (WEST), a research project that aimed to develop bioenergy crops that produce more biomass with less water.Photosynthesis is the natural process that plants use to convert sunlight into energy. Plants usually fall under the two main types of photosynthesis -- C3 and C4. The difference between these types is that C4 plants have a mechanism that concentrates carbon dioxide inside their leaves, allowing them to photosynthesize more efficiently. However, most plants, trees, and crops operate using the less efficient C3 photosynthesis.Both sun and shade leaves contribute to photosynthetic carbon assimilation, producing the sugars that feed the plant and fuel yield. Therefore, lower canopy photosynthesis is an important process that affects the yield of the whole plant, with an estimated 50 percent of total canopy carbon gain contributed by shade leaves.Previous studies of C3 plants have shown that shaded leaves are typically more efficient than sun leaves at low light intensities, meaning shaded leaves adapt to their low light environment. However, a previous study by Pignon and Long showed that this is not the case for all plants. The canopies of maize and Miscanthus, C4 crops that usually photosynthesize more efficiently than C3 crops, had shade leaves that were less photosynthetically efficient, suggesting a maladaptation in these important crops."Shade leaves receive very little light, so they usually become very efficient with low light use," said Pignon, now a plant physiologist at Benson Hill in St. Louis. "Essentially, they make the most of what little light they do receive. However, in the C4 crops we studied, shade leaves in these crops not only receive very little light, but they also use it less efficiently. It's a very costly maladaptation in crops that are otherwise highly productive -- hence our calling it an Achilles' heel."With six to eight layers of leaves in our modern maize crop stands, most leaves are shaded and can account for half of the plant's growth during the critical phase of grain filling."In the previous study, researchers estimated that this maladaptation was causing a loss of 10 percent in potential canopy photosynthesis gain," said Raven, who recently graduated from Oxford with plans to pursue her doctorate. "There are essentially two potential reasons: the age of the leaves or the light conditions, so we investigated which factor was causing this inefficiency."Collison and Raven, co-first authors of this newly published paper, collected data and analyzed the maximum quantum yield of photosynthesis -- the maximum efficiency with which light is used to assimilate carbon -- in leaves of the same chronological age but different light environments to discover the crops' Achilles' heel. This was achieved by comparing leaves of the same age in the center of plots of these species versus those on the sunlight southern edge of these plots. From this, they showed that the poor photosynthetic efficiency of these crops' lower leaves is caused by altered light conditions and not age."Maize and Miscanthus are both closely related to sugarcane and sorghum, so other C4 crops could potentially have this loss in photosynthetic efficiency caused by the light environment," explained Collison, who has also graduated from Oxford and may pursue graduate studies. "By finding the cause of this loss in efficiency, we can begin to look at potential solutions to this problem, modifying plants to improve their productivity."The ISF program has cultivated an environment where the Fellows have the independence needed to develop as scientists while knowing that they have the support and encouragement of their supervisors. Fellows are paired with a scientist supervisor to assist them with a specific element of a project aimed to increase crops' photosynthetic and/or water-use efficiency. The program aims to provide a rewarding experience that helps students develop as scientists, and ultimately, to consider pursuing careers in plant biology."The opportunity to travel to another country and conduct meaningful research in a real-world field environment alongside mentors in their field is invaluable," said Long, who launched and directs the ISF program at the Carl R. Woese Institute for Genomic Biology. "At the end of their time at Illinois, our Fellows have expressed that this experience allowed them to contribute to the world and take back valuable skills they can apply in their future endeavors as innovators in the field of agriculture and beyond."Collison reflects on his time at Illinois as an experience that not many students, especially so early in their career, get to take part in. "The chance to do any research so early in your career as a scientist is really exciting," he said. "Everyone we met -- including our supervisors and other scientists -- was always willing to help us."Raven also shared her insights on the value of doing research at Illinois and what differences there may be in other academic or work settings. "When you are attending lectures or practical classes, you never quite get that feeling of true ownership of your own projects because you just follow whatever your professor tells you to do," Raven said. "But having ownership of this paper at Illinois is gratifying. It is also exciting to be a part of something that is bigger than us and will ultimately help farmers in other countries to grow food more sustainably."
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Agriculture & Food
| 2,020 |
June 24, 2020
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https://www.sciencedaily.com/releases/2020/06/200624082715.htm
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Transgenic rice lowers blood pressure of hypertensive rats
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In the future, taking your blood pressure medication could be as simple as eating a spoonful of rice. This "treatment" could also have fewer side effects than current blood pressure medicines. As a first step, researchers reporting in ACS'
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High blood pressure, also known as hypertension, is a major risk factor for cardiovascular disease and stroke. A common class of synthetic drugs used to treat hypertension, called ACE inhibitors, target the angiotensin converting enzyme (ACE), which is involved in blood pressure regulation. However, ACE inhibitors often have unpleasant side effects, such as dry cough, headache, skin rashes and kidney impairment. In contrast, natural ACE inhibitors found in some foods, including milk, eggs, fish, meat and plants, might have fewer side effects. But purifying large amounts of these ACE-inhibitory peptides from foods is expensive and time-consuming. Le Qing Qu and colleagues wanted to genetically modify rice -- one of the world's most commonly eaten foods -- to produce a mixture of ACE-inhibitory peptides from other food sources.The researchers introduced a gene to rice plants that consisted of nine ACE-inhibitory peptides and a blood-vessel-relaxing peptide linked together, and confirmed that the plants made high levels of the peptides. The researchers then extracted total protein (including the peptides) from the transgenic rice and administered them to rats. Two hours after treatment, hypertensive rats showed a reduction in blood pressure, while rats treated with wild-type rice proteins did not. Treatment of rats over a 5-week period with flour from the transgenic rice also reduced blood pressure, and this effect remained 1 week later. The treated rats had no obvious side effects in terms of growth, development or blood biochemistry. If these peptides have the same effects in humans, a 150-pound adult would need to eat only about half a tablespoon of the special rice daily to prevent and treat hypertension, the researchers say.
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Agriculture & Food
| 2,020 |
June 23, 2020
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https://www.sciencedaily.com/releases/2020/06/200623225443.htm
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Agricultural conservation schemes not enough to protect Britain's rarest butterflies
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Conservation management around the margins of agriculture fail to protect butterfly species at greatest risk from the intensification of farming, a new study says.
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The research, from the University of York, says the subsidised schemes are likely to help common, more mobile grassland species like the Ringlet (Aphantopus hyperantus) or the Meadow brown (Maniola jurtina) but not rarer species like the Duke of Burgundy (Hamearis lucina) or the Dingy skipper (Erynnis tages).Agri-environment schemes financially reward farmers managing land in ways which aim to reduce the environmental impacts of agriculture. Common options include setting aside small areas of land out of production, including leaving grassland strips at the edges of agricultural fields.The study examined whether these strips helped support insects including grassland butterfly populations. It used ecological models to look at whether the schemes improved butterfly survival locally and also if set aside land helped species expand their range and move across landscapes. This expansion is important so that species can move in response to climate change.Katie Threadgill, PhD student from the Department of Biology said: "These kind of set aside schemes help mobile, common butterfly species move across landscapes but they do not help all species."The greatest benefits were seen in species which were either highly mobile or which live in high densities. High density species which could travel further were already successful expanders regardless of set-asides although expansion rates were still improved when set-asides were added. Overall, set-aside strips did increase rates of range expansion across landscapes by up to 100% for some species but they did not boost long term butterfly survival locally.Prof Jane Hill, who co-supervised the project added: "Small-scale set-asides have the potential to improve connectivity, which will help some species move to cope with climate change, and connect up habitat patches for others."The study concluded that set-asides are unlikely to benefit low dispersal, low density species which are probably at greatest risk from agricultural intensification.Katie Threadgill added: "Our results suggest that small set-aside strips alone are not an appropriate solution for preventing extinctions in the long term, but can provide other benefits"
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Agriculture & Food
| 2,020 |
June 22, 2020
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https://www.sciencedaily.com/releases/2020/06/200622152542.htm
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Nanoplastics accumulate in land-plant tissues
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As concern grows among environmentalists and consumers about micro- and nanoplastics in the oceans and in seafood, they are increasingly studied in marine environments, say Baoshan Xing at the University of Massachusetts Amherst and colleagues in China. But "little is known about the behavior of nanoplastics in terrestrial environments, especially agricultural soils," they add.
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Xing, an environmental scientist at UMass Amherst's Stockbridge School of Agriculture, and collaborators at Shandong University, China, point out that until now, there had been no direct evidence that nanoplastics are internalized by terrestrial plants.They state, "Our findings provide direct evidence that nanoplastics can accumulate in plants, depending on their surface charge. Plant accumulation of nanoplastics can have both direct ecological effects and implications for agricultural sustainability and food safety." Both positively and negatively charged nanoplastics accumulate in the commonly used laboratory model plant, Arabidopsis thaliana.Xing adds that widespread global use and persistence in the environment result in an "enormous" amount of plastic waste. He says, "Our experiments have given us evidence of nanoplastics uptake and accumulation in plants in the laboratory at the tissue and molecular level using microscopic, molecular and genetic approaches. We have demonstrated this from root to shoot." Details are in Xing points out that nanoplastic particles can be as small as a protein or a virus. Weathering and degradation change plastic's physical and chemical properties and imparts surface charges, so environmental particles are different from the pristine polystyrene nanoplastics often used in the lab. "This is why we synthesized polystyrene nanoplastics with either positive or negative surface charges for use in our experiments."He helped to design the study, interpret the results, evaluate and revise the manuscript while a large team at Shandong University led by Xian-Zheng Yuan and Shu-Guang Wang conducted the experiments.They grew Arabidopsis plants in soil mixed with differently charged, fluorescently labeled nanoplastics to assess plant weights, height, chlorophyll content and root growth. After seven weeks, they observed that plant biomass and height were lower in plants exposed to nanoplastics than in controls, for example."Nanoplastics reduced the total biomass of model plants," Xing adds. "They were smaller and the roots were much shorter. If you reduce the biomass, it's not good for the plant, yield is down and the nutritional value of crops may be compromised."He adds, "We found that the positively charged particles were not taken up so much, but they are more harmful to the plant. We don't know exactly why, but it's likely that the positively charged nanoplastics interact more with water, nutrients and roots, and triggered different sets of gene expressions. That needs to be explored further in crop plants in the environment. Until then, we don't know how it may affect crop yield and food crop safety."The team also analyzed seedlings to investigate sensitivity of the roots to charged nanoplastics. Exposed for 10 days, seedling growth was inhibited compared with that of control seedlings. To identify molecular mechanisms responsible, the researchers used RNA-Seq transcriptomic analyses of roots and shoots, then verified results with a quantitative PCR assay on three root genes and four shoot genes."Regardless of the surface charge, Arabidopsis can take up and transport nanoplastics with sizes of less than 200 nm," they write. Further, "In this study, we mainly demonstrate that the pathway of uptake and transport of nanoplastics in root tissues differed between differentially charged nanoplastics."
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Agriculture & Food
| 2,020 |
June 18, 2020
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https://www.sciencedaily.com/releases/2020/06/200618120147.htm
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Innovation by ancient farmers adds to biodiversity of the Amazon
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Innovation by ancient farmers to improve soil fertility continues to have an impact on the biodiversity of the Amazon, a major new study shows.
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Early inhabitants fertilized the soil with charcoal from fire remains and food waste. Areas with this "dark earth" have a different set of species than the surrounding landscape, contributing to a more diverse ecosystem with a richer collection of plant species, researchers from the State University of Mato Grosso in Brazil and the University of Exeter have found.The legacy of this land management thousands of years ago means there are thousands of these patches of dark earth dotted around the region, most around the size of a small field. This is the first study to measure the difference in vegetation in dark and non-dark earth areas in mature forests across a region spanning a thousand kilometers.The team of ecologists and archaeologists studied abandoned areas along the main stem of the Amazon River near Tapajós and in the headwaters of the Xingu River Basin in southern Amazonia.Lead author Dr Edmar Almeida de Oliveira said: "This is an area where dark earth lush forests grow, with colossal trees of different species from the surrounding forest, with more edible fruit trees, such as taperebá and jatobá."The number of indigenous communities living in the Amazon collapsed following European colonization of the region, meaning many dark earth areas were abandoned.The study, published in the journal Researchers sampled around 4,000 trees in southern and eastern Amazonia. Areas with dark earth had a significantly higher pH and more nutrients that improved soil fertility. Pottery shards and other artefacts were also found in the rich dark soils.Professor Ben Hur Marimon Junior, from the State University of Mato Grosso, said: "Pre-Columbian indigenous people, who fertilized the poor soils of the Amazon for at least 5,000 years, have left an impressive legacy, creating the dark earth, or Terras Pretas de Índio"Professor José Iriarte, an archaeologist from the University of Exeter, said: "By creating dark earth early inhabitants of the Amazon were able to successfully cultivate the soil for thousands of years in an agroforestry system"We think ancient communities used dark earth areas to grow crops to eat, and adjacent forests without dark earth for agroforestry."Dr Ted Feldpausch, from the University of Exeter, who co-authored the study with Dr Luiz Aragão from the National Institute for Space Research (INPE) in Brazil, said: "After being abandoned for hundreds of years, we still find a fingerprint of the ancient land-use in the forests today as a legacy of the pre-Colombian Amazonian population estimated in millions of inhabitants."We are currently expanding this research across the whole Amazon Basin under a project funded by the UK Natural Environment Research Council (NERC) to evaluate whether historical fire also affected the forest areas distant from the anthropogenic dark earths."Many areas with dark earth are currently cultivated by local and indigenous populations, who have had great success with their food crops. But most are still hidden in the native forest, contributing to increased tree size, carbon stock and regional biodiversity. For this reason, the lush forests of the "Terra Preta de Índio" and their biological and cultural wealth in the Amazon must be preserved as a legacy for future generations, the researchers have said. Areas with dark earth are under threat due to illegal deforestation and fire."Dark earth increases the richness of species, an important consideration for regional biodiversity conservation. These findings highlight the small-scale long-term legacy of pre-Columbian inhabitants on the soils and vegetation of Amazonia," said co-author Prof Beatriz Marimon, from the State University of Mato Grosso.
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Agriculture & Food
| 2,020 |
June 17, 2020
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https://www.sciencedaily.com/releases/2020/06/200617150015.htm
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Tomato's hidden mutations revealed in study of 100 varieties
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Human appetites have transformed the tomato -- DNA and all. After centuries of breeding, what was once a South American berry roughly the size of a pea now takes all sorts of shapes and sizes, from cherry-like to hefty heirloom fruit.
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Today, scientists are teasing out how these physical changes show up at the level of genes -- work that could guide modern efforts to tweak the tomato, says Howard Hughes Medical Institute Investigator Zachary Lippman.He and colleagues have now identified long-concealed hidden mutations within the genomes of 100 types of tomato, including an orange-berried wild plant from the Galapagos Islands and varieties typically processed into ketchup and sauce.Their analysis, described June 17, 2020, in the journal Previous studies have long shown that these mutations exist in plant genomes, says Lippman, a plant geneticist at Cold Spring Harbor Laboratory. "But until now, we didn't have an efficient way to find them and study their impact," he says.Mutations, or changes, in the four types of DNA letters carried within an organism's cells can alter its physical characteristics. Scientists studying plants have generally focused on a small, tractable kind of mutation, in which one DNA letter is swapped for another.The mutations Lippman's team studied are much bigger -- they modify DNA's structure by copying, deleting, inserting, or moving long sections of DNA elsewhere in the genome. These mutations, also called structural variations, occur throughout the living world. Studies in humans, for example, have linked these variations to disorders such as schizophrenia and autism.Scientists can identify mutations by reading out the letters of DNA using a technique known as genetic sequencing. Limitations in this technology, however, have made it difficult to decode long sections of DNA, Lippman says. So researchers haven't been able to capture a complete picture of structural mutations in the genome.Even so, plant geneticists have suspected that these mutations contribute significantly to plants' traits, says Michael Purugganan, who studies rice and date palms at New York University and was not involved in the new study. "That's why this paper is so exciting," he says. Lippman's team not only found these mutations in tomato and its wild relatives, but also determined how they function within the plants, he says.The new study, a collaboration with Michael Schatz at Johns Hopkins University and others, identified more than 200,000 structural mutations in tomatoes using a technique called long-read sequencing. Lippman likens it to looking through a panoramic window at large sections of the genome. By comparison, more conventional sequencing offered only a peephole, he says.The majority of the mutations they found do not change genes that encode traits. But what's clear, Lippman says, is that many of these mutations alter mechanisms controlling genes' activity. One such gene, for instance, controls tomato fruit size. By modifying DNA structure -- in this case, the number of copies of the gene -- Lippman's team was able to alter fruit production. Plants lacking the gene never made fruit, while plants with three copies of the gene made fruit about 30 percent larger than those with just a single copy.Lippman's team also demonstrated how DNA structure can influence traits in an example he calls "remarkably complex." They showed that four structural mutations together were needed for breeding a major harvesting trait into modern tomatoes.These sorts of insights could help explain trait diversity in other crops and enable breeders to improve varieties, Lippman says. For instance, perhaps adding an extra copy of the size gene to tiny ground cherries, a close relative of the tomato, could increase their appeal by making them larger, he says."One of the holy grails in agriculture is to be able to say, 'If I mutate this gene, I know what the output will be,'" he says. "The field is making important steps toward this kind of predictable breeding."
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Agriculture & Food
| 2,020 |
June 17, 2020
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https://www.sciencedaily.com/releases/2020/06/200617145957.htm
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What it means when animals have beliefs
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Humans are not the only ones who have beliefs; animals do too, although it is more difficult to prove them than with humans. Dr. Tobias Starzak and Professor Albert Newen from the Institute of Philosophy II at Ruhr-Universität Bochum have proposed four criteria to understand and empirically investigate animal beliefs in the journal
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The first criterion for the existence of beliefs worked out by the philosophers is that an animal must have information about the world. However, this must not simply lead to an automatic reaction, like a frog instinctively snapping at a passing insect.Instead, the animal must be able to use the information to behave in a flexible manner. "This is the case when one and the same piece of information can be combined with different motivations to produce different behaviours," explains Albert Newen. "For example, if the animal can use the information that there is food available at that moment for the purpose of eating or hiding the food."The third criterion says that the information is internally structured in a belief; accordingly, individual aspects of that information can be processed separately. This has emerged, for example, in experiments with rats that can learn that a certain kind of food can be found at a certain time in a certain place. Their knowledge has a what-when-where structure.Fourthly, animals with beliefs must be able to recombine the information components in novel ways. This reassembled belief should then lead to flexible behaviour. Rats can do this too, as the US researcher Jonathan Crystal demonstrated in experiments in an eight-armed labyrinth. The animals learned that if they received normal food in arm three of the maze in the morning, chocolate could be found in arm seven at noon.The authors from Bochum also cite crows and scrub jays as examples of animals with beliefs. British researcher Nicola Clayton carried out conclusive experiments with scrub jays. When the birds are hungry, they initially tend to eat the food. When they are not hungry, they systematically hide the leftovers. In the process, they encode which food -- worm or peanut -- they have hidden where and when. If they are hungry in the following hours, they first look for the worms they prefer. After the period of time has elapsed that takes worms to become inedible, they head for the peanut hiding places instead."What best explains this change in behaviour is the birds' belief about the worms being spoiled and their beliefs about the location of other food items," says Tobias Starzak. The animals also react flexibly in other situations, for example if they notice that they are being watched by rivals while hiding; if this is the case, they hide the food again later.Flexible behaviour, which can be interpreted as caused by beliefs, has also been shown in rats, chimpanzees and border collies. "But probably many more species have beliefs," supposes Albert Newen.
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Agriculture & Food
| 2,020 |
June 17, 2020
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https://www.sciencedaily.com/releases/2020/06/200617145954.htm
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Gut bacteria may modify behavior in worms, influencing eating habits
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Gut bacteria are tiny but may play an outsized role not only in the host animal's digestive health, but in their overall well-being. According to a new study in
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"We keep finding surprising roles for gut bacteria that go beyond the stomach," said Robert Riddle, Ph.D., program director at the NIH's National Institute of Neurological Disorders and Stroke (NINDS), which supported the study. "Here, the gut bacteria are influencing how the animal senses its environment and causing it to move toward an external source of the same bacteria. The gut bacteria are literally making their species tastier to the animal."Researchers at Brandeis University, Waltham, Massachusetts, led by Michael O'Donnell, Ph.D., postdoctoral fellow and first author of the paper, and Piali Sengupta, Ph.D., professor of biology and senior author of the study, were interested in seeing whether it was possible for gut bacteria to control a host animal's behavior. The group investigated the effects of gut bacteria on how worms, called C. elegans, sniff out and choose their next meal.Bacteria are the worms' primary food. In this study, the researchers measured how worms fed different strains of bacteria reacted to octanol, a large alcohol molecule secreted by some bacteria, which worms normally avoid when it is present at high concentrations.Dr. O'Donnell and his colleagues discovered that worms grown on Providencia alcalifaciens (JUb39) were less likely to avoid octanol compared to animals grown on other bacteria. Curiously, they found that live JUb39 bacteria were present in the gut of the worms that moved toward octanol, suggesting that the behavior may be determined in part by a substance produced by these bacteria.Next, the researchers wanted to know how the bacteria exerted control over the worms."We were able to connect the dots, all the way from microbe to behavior, and determine the entire pathway that could be involved in this process," said Dr. O'Donnell.The brain chemical tyramine may play an important role in this response. In the worms, tyramine is transformed into the chemical octopamine, which targets a receptor on sensory neurons that controls avoidance behavior. The results of this study suggested that tyramine produced by bacteria increased levels of octopamine, which made the worms more tolerant of octanol by suppressing the avoidance of octanol that is driven by these neurons.Using other behavioral tests, the researchers found that genetically engineering worms so that they did not produce tyramine did not affect suppression of octanol avoidance when the worms were grown on JUb39. This suggests that tyramine made by the bacteria may be able to compensate for the endogenous tyramine missing in those animals.Additional experiments indicated that worms grown on JUb39 preferred eating that type of bacteria over other bacterial food sources. Tyramine produced by the bacteria was also found to be required for this decision."In this way, the bacteria can take control over the host animal's sensory decision-making process, which affects their responses to odors and may influence food choices" said Dr. Sengupta.Future studies will identify additional brain chemicals produced by bacteria that may be involved in changing other worm behaviors. In addition, it is unknown whether specific combinations of bacterial strains present in the gut will result in different responses to environmental cues. Although worms and mammals share many of the same genes and biochemical processes, it is not known whether similar pathways and outcomes exist in higher order animals.
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Agriculture & Food
| 2,020 |
June 17, 2020
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https://www.sciencedaily.com/releases/2020/06/200617121440.htm
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Weed's wily ways explained
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Like antibiotic-resistant bacteria, some herbicide-resistant weeds can't be killed by available chemicals. The problem affects more than just the errant weed in our driveways; herbicide-resistant weeds threaten our food supply, stealing resources and outcompeting the crops that make up our breakfast cereal and feed the nation's livestock.
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The weed that represents the biggest threat to Midwestern corn and soybean production, waterhemp, has outsmarted almost every kind of herbicide on the market today.University of Illinois scientists are working to reveal waterhemp's tricks. Through years of research, they discovered the weed can ramp up production of detoxifying enzymes that neutralize certain herbicides before they can disrupt essential cellular processes. Metabolic resistance, as this strategy is known, is just one process by which waterhemp evades herbicides. Unfortunately, because there may be hundreds of detoxifying enzymes involved, metabolic resistance is hard to identify and even harder to combat.In two recent studies, Illinois researchers explain metabolic resistance to three commonly used herbicides in waterhemp, getting closer to finding important genetic cues. Results also confirm the importance of using a multi-pronged approach to waterhemp control."These waterhemp populations are adapting and evolving incredible abilities to metabolize everything. It's bad news, but at least we understand the mechanisms better. And ultimately, that understanding could potentially be exploited to use waterhemp's metabolic arsenal against itself," says Dean Riechers, professor in the Department of Crop Sciences at Illinois and co-author on both studies. "That's one interesting way our research could be directly applied to controlling this weed."Last year, Illinois researchers documented resistance to Group 15 herbicides in waterhemp. This group of herbicides, including S-metolachlor, targets very-long-chain fatty acid production in sensitive plants. The researchers suspected it was also a case of metabolic resistance, and the Illinois team, led by graduate student Seth Strom, has now confirmed it in a study published in "We were the first group in the world to show resistance to Group 15 herbicides in waterhemp, and now we have identified the mechanism behind it," Riechers says. "Again, it's not good news because it means we're running out of herbicides, and in this case it involves pre-emergence herbicides."The study suggests two classes of detoxifying enzymes, known as GSTs and P450s, appear to neutralize S-metolachlor in resistant waterhemp.Group 15 herbicides can be safely used in corn because the crop uses GSTs to naturally detoxify the chemicals; in other words, corn has a natural tolerance to these chemicals. Strom's research suggests waterhemp is not only able to mimic corn's natural detoxification mechanism, but it evolved an additional way to avoid being harmed by S-metolachlor.Honing in on the two classes of detoxifying enzymes is not the end of the story, however. Because plants have hundreds of enzymes in each class, the researchers have more work ahead of them to identify the specific genes that are activated.In a separate study, Riechers and another group of Illinois scientists revealed more of waterhemp's metabolic secrets."We have known for the last 10 years that whenever we see waterhemp with resistance to an HPPD inhibitor in the field, such as mesotrione, it has always shown metabolic atrazine resistance, too. However, it is possible for waterhemp to be resistant to atrazine and not mesotrione," Riechers says.The apparent association between mesotrione and metabolic atrazine resistance could be coincidental, but given how often the resistances co-occur, Riechers thought the genes controlling resistance for the two chemicals might be shared or linked.In a study published in "Whenever we find out whether it's two or three or four genes involved in mesotrione resistance, our results tell us one of them should be the metabolic atrazine resistance gene," Riechers says. "We know which one that is."Unfortunately, even if researchers are able to trace each resistance trait back to the genetic level, that won't ensure an easy solution to the problem. Experts say there are no new herbicide sites-of-action coming into the marketplace, so farmers will need to consider alternative methods of weed control."With metabolic resistance, our predictability is virtually zero. We have no idea what these populations are resistant to until we get them under controlled conditions. It's just another example of how we need a more integrated system, rather than relying on chemistry only. We can still use the chemistry, but have to do something in addition," says Aaron Hager, associate professor in the Department of Crop Sciences at Illinois and co-author on the Pest Management Science study. "We have to rethink how we manage waterhemp long term."
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Agriculture & Food
| 2,020 |
June 17, 2020
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https://www.sciencedaily.com/releases/2020/06/200617091007.htm
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Crop residue decisions affect soil life
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In some ways, farming is like cooking. Cooking would be much easier if we could leave the kitchen after eating and not come back until we make the next meal. But someone needs to put away the leftovers, do the dishes, and clean up the table.
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Similarly, there's work to do in farm fields after harvest and before planting the next spring.After harvest in the fall, farmers take the harvested crops to market or store them on their farm. They don't take the whole plant from the field, though.The leftover parts of the plant, like the stalk and leaves from corn, remain in the field. This debris is called crop residue.Using no-till and prescribed fire management are two potential ways to manage crop residue. Both practices help keep organic matter and nitrogen in the soil. However, research was needed to understand how these two practices can affect long-term soil health.Lisa Fultz and her team want to help farmers determine the best way to manage their residue between growing seasons. To do this, her team decided to learn more about how no-till and prescribed fire management affect nutrients and microbes in the soil. Fultz is a researcher at Louisiana State University AgCenter.No-till is a practice where farmers plant directly into the crop debris from the previous year. Prescribed fires are used to purposely burn off the previous crop debris with controlled fire. "Both of these practices have minimal physical disturbance to the soil," says Fultz.Both of these practices also come with drawbacks. No-till can cause poor conditions for crop growth like low spring temperatures and increased moisture, which promotes disease. Prescribed fire can leave bare soil vulnerable to erosion.The team focused the research on wheat and soybean rotations and continuous corn production systems. "These are common practices not only in the mid-south, but across many areas of the world," explains Fultz."Wheat and corn production leave behind residue," she says. "Common practices, like conventional tillage, are highly disruptive. The need to identify viable conservation practices is growing in importance."Crop residue and its degradation by soil microbes is an important part of the carbon cycle. Plants store carbon during the growing season, then microbes use the plant residue for food. The carbon then gets stored in the soil in a chemically stable form."Fresh, green material in no-till fields is easy to breakdown and provides rich nutrients for soil microbes," says Fultz. "Ash from burned residue is more chemically stable, but it doesn't provide a nutrient source for microbes."The team found that impacts from crop management practices, like crop rotation or fertilization, outweighed the influence of prescribed fire for residue management. Researchers found some decreases in microbial activity after yearly prescribed burns.Findings show prescribed fire had some possible short-term benefits for soil nutrient availability, but timing is crucial. Prescribed burning of wheat residue provided an increase of nitrogen for about 7 days. These benefits should be weighed against other possible impacts, like carbon dioxide production and crop yield.We still need to learn the long-term influence of prescribed fire on the soil biological community," says Fultz. "While short-term impacts were measured, the long-term influence on soil nutrients, biological cycles and soil health are not known."No two farm management systems are the same, and their success is defined by the user. Scientists continue to examine possible scenarios to provide accurate and sustainable recommendations to farmers."I have always been interested in soil conservation and the potential it has to impact many facets of life," says Fultz. "By improving soil health, we can improve air and water quality, store carbon, and provide stable resources for food production."
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Agriculture & Food
| 2,020 |
June 16, 2020
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https://www.sciencedaily.com/releases/2020/06/200616155951.htm
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Honeybee lives shortened after exposure to two widely used pesticides
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The lives of honeybees are shortened -- with evidence of physiological stress -- when they are exposed to the suggested application rates of two commercially available and widely used pesticides, according to new Oregon State University research.
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In a study published in the journal The western honeybee is the major pollinator of fruit, nut, vegetable and seed crops that depend on bee pollination for high quality and yield.Coupled with other stressors such as varroa mites, viruses and poor nutrition, effects from these pesticides can render honeybees incapable of performing their tasks smoothly. Beekeepers and some environmental groups have raised concerns in recent years about these insecticides and potential negative effects on bees.According to the researchers, this is the first study to investigate "sub-lethal" effects of sulfoxaflor, the active ingredient in Transform, and flupyradifurone, the active ingredient in Sivanto. Sub-lethal effects mean that the bees don't die immediately, but experience physiological stress resulting in shortened lifespan.In the case of Transform, the bees' lives were severely shortened. A majority of the honeybees exposed to Transform died within six hours of being exposed, confirming the severe toxicity of the pesticide to bees when exposed directly to field application rates recommended on the label, the researchers said.Study lead author Priyadarshini Chakrabarti Basu, a postdoctoral research associate in the Honey Bee Lab in OSU's College of Agricultural Sciences, emphasized that the researchers aren't calling for Sivanto or Transform to be taken off the market."We are suggesting that more information be put on the labels of these products, and that more studies need to be conducted to understand sublethal effects of chronic exposure," Basu said.Sivanto and Transform are used on crops to kill aphids, leaf hoppers and whiteflies, among other pests. Many of these same crops attract bees for pollination. There are some restrictions on their use. For example, Transform can't be applied to crops in bloom, for example.Honeybees might be exposed indirectly through pesticide drift, said study co-author Ramesh Sagili, associate professor of apiculture and honeybee Extension specialist in OSU's College of Agricultural Sciences."The average life span of a worker honeybee is five to six weeks in spring and summer, so if you are reducing its life span by five to 10 days, that's a huge problem," Sagili said. "Reduced longevity resulting from oxidative stress could negatively affect colony population and ultimately compromise colony fitness."For the study, the researchers conducted two contact exposure experiments: a six-hour study and a 10-day study in May 2019. The honeybees were obtained from six healthy colonies at the OSU apiaries. In each experiment, groups of 150 bees were placed in three cages. One group was exposed to Transform, a second to Sivanto and the third was a control group that wasn't exposed to either pesticide.Honeybee mortality, sugar syrup and water consumption, and physiological responses were assessed in bees exposed to Sivanto and Transform and compared to bees in a control group. Mortality in each cage was recorded every hour for the six-hour experiment and daily for the 10-day experiment.While Sivanto was not directly lethal to honeybees following contact exposure, the 10-day survival results revealed that field-application rates of Sivanto reduced adult survival and caused increased oxidative stress and apoptosis in the honey bee tissues. This suggests that even though Sivanto is apparently less toxic than Transform, it might also reduce honeybee longevity and impart physiological stress, according to the study authors.Co-authors on the study included graduate student Emily Carlson and faculty research assistant Hannah Lucas, who both conduct research in the Honey Bee Lab; and Andony Melathopoulos, assistant professor and pollinator health Extension specialist.
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Agriculture & Food
| 2,020 |
June 16, 2020
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https://www.sciencedaily.com/releases/2020/06/200616135816.htm
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Newly discovered plant gene could boost phosphorus intake
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Researchers from the University of Copenhagen have discovered an important gene in plants that could help agricultural crops collaborate better with underground fungi -- providing them with wider root networks and helping them to absorb phosphorus. The discovery has the potential to increase agricultural efficiency and benefit the environment.
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It is estimated that about 70 percent of phosphorus fertilizer used in Danish agriculture accumulates in soil, whereas only 30 percent of it reaches plants.Quid pro quo -- that's how one might describe the "food community" that the majority of plants have with mycorrhizal fungi. Plants allow fungi to live among their roots, while feeding them fat and sugar. And in return, fungi use their far-reaching hypha (filamentous branches) to capture vital soil nutrients for plants, including the important mineral phosphorus.Now, researchers at the University of Copenhagen's Department of Plant and Environmental Sciences have discovered an extraordinary plant gene, the CLE53 gene, which regulates cooperation between fungi and plants. The gene is central to a mechanism that controls how receptive plants are to working with mycorrhizal fungi. Down the road, this newfound knowledge could serve to deliver better harvests and reduced fertiliser use."Similar genes are found in all plants -- including agricultural crops. So, by mutating or turning off the CLE53 gene in a crop plant, it is more likely for a plant to become symbiotically involved with a fungus. In doing so, it becomes possible to reduce the need for phosphorus fertilizers, as plants improve at absorbing preexistent phosphorus from soil," explains Assistant Professor Thomas Christian de Bang of the Department of Plant and Environmental Sciences.The research has been published in the Phosphorus is vital for all plants. However, the problem with phosphorus use in agriculture is that more of it is applied for fertilisation than can be absorbed by crops. It is estimated that about 70 percent of phosphorus fertilizer used in Danish agriculture accumulates in soil, whereas only 30 percent of it reaches plants. With rain, there is an ever present risk that some of the accumulated phosphorus will be discharged into streams, lakes and the sea.Paradoxically, researchers have observed that when phosphorus levels in soil are high, plants are less likely to collaborate with fungi, meaning that they become worse at absorbing nutrients."Through a range of experiments, we have demonstrated that a plant does not produce the CLE53 gene if it lacks phosphorus. However, when the phosphorus levels in a plant are high, or if the plant is already symbiotically involved with a fungus, then the level of CLE53 increases. Our study demonstrates that CLE53 has a negative effect on a plant's ability to enter into symbiosis with a fungus, and thereby absorb phosphorus most effectively," says Thomas Christian de Bang.The genomic editing of plants is legal in a number of non-EU countries -- e.g., China, the US, Switzerland and the UK. However, within the EU, there is no general acceptance of gene-editing methods, such as CRISPR, to alter plants and foodstuffs.Therefore, the researchers' discovery has, for the time being, a poorer chance of being used in Denmark and the rest of the EU."One can use the technology in other parts of the world, and getting started would be relatively straightforward. My guess is that within five years, plants will be tested and refined in such a way that they become more symbiotically involved with fungi and absorb more phosphorus. Here in Denmark and throughout the EU, an acceptance is required for gene editing and an amended approach to approval procedures for these types of plants," says Thomas Christian de Bang.90% of all plants engage in symbiotic relationships with mycorrhizal fungi, which popularly said, extend the root networks of plants, thus helping them to obtain enough phosphorus, water and other nutrients.In order to benefit from the ability of mycorrhizal fungi to extract phosphorus from soil, a plant must feed it with fat and sugar. To avoid spending too much energy on the sponge, if for example, it is experiencing high phosphorus levels or has already been colonised by a fungus, the plant may switch off symbiosis.It is estimated that Danish farms fertilise with roughly 30 kilos of phosphorus per hectare of land.Of this, roughly 30 percent makes its way to crops, while the remaining 70 percent binds to soil.With rain, some of this accumulated phosphorus is flushed away via surface runoff, into nearby streams, lakes and the sea. This increases algae growth and can kill both plants and wildlife.Phosphorus is a finite natural resource, one that is expected to eventually be depleted.The research is funded by the Novo Nordisk Foundation and the University of CopenhagenPrevious research has shown that a similar mechanism exists for symbiosis between legumes and rhizobium bacteria. This involved a CLE gene as well, albeit a different one than the researchers have now discovered.
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Agriculture & Food
| 2,020 |
June 16, 2020
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https://www.sciencedaily.com/releases/2020/06/200616135746.htm
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Cattle vs. hippopotamus: Dung in rivers of the Savannah
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In many regions of the world, populations of large mammalian herbivores have been displaced by cattle breeding, for example in Kenya the hippos by large herds of cattle. This can change aquatic ecosystems due to significant differences in the amount and type of dung input. Researchers from the University of Eldoret in Kenya, the University of Innsbruck and the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB) have therefore taken a closer look at the dung of hippopotamus and cattle.
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Animal dung can pollute water bodies with nutrients and impact water quality and the ecological functions of water bodies. For many aquatic ecosystems, however, the input of organic matter from the surrounding land is part of the natural matter cycling. In temperate latitudes, it is the leaf fall that brings nutrients into water bodies. In the rivers of the African savannah, it is the hippos with their dung. The increasing displacement of hippopotami by herds of cattle is changing the nutrient inputs into water bodies.Professor Gabriel Singer, Dr. Frank O. Masese and their team investigated the effects of nutrient and carbon inputs from dung on aquatic ecosystems in experiments. The researchers also developed a mathematical model to compare dung inputs from cattle and hippos into the Mara River in Kenya. According to the mathematical simulation, despite lower manure introduction by the individual cattle compared to a hippopotamus, the large number of cattle gives this animal group overwhelming influence.With cattle dung, higher amounts of nutrients such as nitrogen, phosphorus and dissolved organic carbon enter the Mara River. In the experiments, the researchers were able to show that, as a result, more plant biomass is formed with cattle dung. The biomass of bacteria and algae was also higher than with hippopotamus dung. This can change food webs in the river."Just the exchange of an animal species that lives on the edge of the river changes the ecological status of the river. Our results show the high species-specific importance of the various large herbivores; they also show how changes in land use or the composition of the species lead to unintended consequences that are not initially the focus of management measures, but which must always be taken into account. Especially with such crucial ecosystems as the waters of the savannah," Gabriel Singer explains the significance of the investigation.
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Agriculture & Food
| 2,020 |
June 16, 2020
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https://www.sciencedaily.com/releases/2020/06/200616100818.htm
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Origins of the beloved guinea pig
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New University of Otago research sheds light on guinea pig domestication and how and why the small, furry animals became distributed around the world.
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Just published in the international science journal, It builds on previous research over many years by Professor of Biological Anthropology, Lisa Matisoo-Smith, tracing the DNA from plants and animals that Pacific settlers carried in their canoes and using that as a proxy for identifying human population origins and tracking their movement around the Pacific.As part of her Otago Master's thesis research in Professor Matisoo-Smith's lab, Edana Lord, now at Stockholm University, Sweden and Dr Catherine Collins from Otago's Department of Anatomy and other international researchers, set about finding out where the guinea pigs that were introduced to the islands of the Caribbean came from.Professor Matisoo-Smith explains it is generally accepted that modern guinea pigs were domesticated in the Andes region of what is now Peru. As an important food item that was also included in religious ceremonies, they were transported and traded around South America.Sometime around AD500, guinea pigs were taken out to the islands of the Caribbean, through at least one of several established trade networks. The researchers expected that the guinea pigs found in the Caribbean would came from Colombia, one of the closer locations in South America to the Caribbean.Using ancient DNA of guinea pigs remains excavated from several sites in the Caribbean, Peru, Colombia, Bolivia, Europe and North America, they found the guinea pigs on the islands did not originate in Colombia, but most likely originated in Peru.What was a bigger surprise to the team was that the guinea pig remains found in the Colombian Highlands appeared to be from a totally different species. This suggests that guinea pig domestication likely took place independently in both Peru and Colombia.The genetic information, along with archaeological contexts, also shows how the guinea pigs had different roles through time."They were and still are important food item in many parts of South America and cultures that derived from South America -- people took them live to introduce to new islands where they were not native or they traded them for other goods," Professor Matisoo-Smith explains."The guinea pig was brought to Europe in the late 1500s or early 1600s by the Spanish and to North America in the early 1800s as part of the exotic pet trade. In the 18th century guinea pigs began to be used by medical researchers as laboratory animals because they have many biological similarities to humans, thus the origin of the phrase 'being a guinea pig' in research."All guinea pigs today -- pets, those that are sold for meat in South America and Puerto Rico, and those used in medical research -- are derived from the Peruvian domesticated guinea pigs."Why the guinea pig was viewed as a pet in some cultures and a food source in others can likely be attributed to long-established cultural notions of what is acceptable as food.Professor Matisoo-Smith says the research demonstrates that the history of guinea pigs is more complex than previously known and has implications for other studies regarding mammal domestication, translocation and distribution."Identifying the origins of the guinea pig remains from the Caribbean helps us to understand how the human trade networks in the region moved in the past 1000 years or so."Through this analysis of ancient guinea pig DNA, we better understand the history of human social interactions over thousands of years and across three continents. It also provides a critical historical perspective of the genetic diversity in guinea pigs and the relationship humans have had with this important domestic animals."
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Agriculture & Food
| 2,020 |
June 15, 2020
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https://www.sciencedaily.com/releases/2020/06/200615184148.htm
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Coffee, cocoa and vanilla: An opportunity for more trees in tropical agricultural landscapes
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The cultivation of coffee, cocoa and vanilla secures the income of many small-holder farmers and is also a driver of land-use change in many tropical countries. In particular, cultivation in agroforestry systems, in which these crops are combined with trees that provide shade, is often considered to have great potential for ecologically sustainable cultivation. Researchers at the University of Göttingen are now showing that the land-use history of agroforestry systems plays a crucial role in assessing the sustainability of agroforestry. The results have been published in the journal
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Tropical agroforests differ greatly in their land-use history, i.e. the former use of the land now occupied by agroforests. On the one hand, an agroforest can be established directly in a forest -- in this case the undergrowth is removed and replaced by vanilla vines, coffee or cocoa bushes. In the process, many plant and animal species and important ecosystem services are lost. On the other hand, an agroforest can be established on land that is open -- for example on a pasture or cornfield which was forest in former times but had been cleared for farming. In this case, the land would be replanted with trees, and so animal species that depend on trees may benefit. Trees also store carbon and may have a cooling effect, which can reduce global warming."Our results show that agroforestry systems can only lead to a significant enhancement of the landscape for biodiversity if they are established on open land," says Dominic Martin, first author of the study. "The conversion of the remaining species-rich tropical forests into coffee, cocoa or vanilla plantations should, however, be avoided." This requires incentives, adds Professor Holger Kreft, Head of the Biodiversity, Macroecology and Biogeography Group at the University of Göttingen. "Sustainability labels should take this into account and avoid giving certification to plantations that were previously forest. It is really only in this way that the ecological advantages of cultivation in agroforestry systems can be achieved. This can then help to ensure that our morning coffee can be enjoyed without a bitter aftertaste," says Kreft.
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Agriculture & Food
| 2,020 |
June 15, 2020
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https://www.sciencedaily.com/releases/2020/06/200615115748.htm
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Vegetarians tend to be slimmer and less extroverted than meat eaters, study finds
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According to a survey by the Allensbach Institute, more than 6.1 million Germans stated last year that they were vegetarians, 400,000 more than two years earlier. A large-scale study at the Max Planck Institute for Human Cognitive and Brain Sciences (MPI CBS) in cooperation with the University Hospital of Leipzig has now examined in almost 9,000 people how this form of nutrition is related to the body and the psyche -- regardless of age, gender and level of education.
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It was found that the rarer the proportion of animal food in a person's diet, the lower their body mass index (BMI) on average and thus their body weight. One reason for this could be the lower proportion of heavily processed foods in the plant diet. "Products that are excessively rich in fat and sugar are particularly fattening. They stimulate the appetite and delay the feeling of satiety. If you avoid animal foods, you consume fewer such products on average," explains Evelyn Medawar, first author of the underlying publication, which has now been published in the journal For the BMI it also seems to make a difference which animal products a person feeds on. If it is predominantly so-called primary animal products, i.e. meat, sausage and fish, the person usually has a higher BMI than someone who eats primarily secondary animal products, i.e. eggs, milk, dairy products, cheese and butter. In the former case the correlation is statistically significant.Medawar uses an example to illustrate what this could mean for nutrition: "A person with a 1.2 point lower BMI on average either completely avoids certain animal products, such as the primary ones, and is on a vegetarian diet. Or she continues to eat meat and fish, but less often. Whether nutrition is ultimately the cause of lower body weight or whether other factors are responsible for it cannot be determined from the data. A follow-up study in cooperation with the University Hospital Leipzig will now shed light on this.The researchers also found out that vegetarian or vegan nutrition is also related to personality. Especially with one of the five major personality factors, extroversion. It was shown that people with predominantly plant-based foods on their diet are more introverted than those who mainly fed on animal products. "It is difficult to say what the reason for this is," says Veronica Witte. "It could be because more introverted people tend to have more restrictive eating habits or because they are more socially segregated because of their eating habits." Here, again, further studies should follow on how people identify with the characteristics of their diet.However, they could not confirm that a plant-based diet is associated with a tendency towards neurotic behaviour, as other studies suggested. "Earlier analyses had found that more neurotic people were generally more likely to avoid certain groups of foods and to behave more restrictively. We focused here solely on the avoidance of animal products and could not observe any correlation," explains study leader Veronica Witte.In a third part, they finally concentrated on the question of whether a predominantly plant-based diet is more often associated with depressive moods. Here previous studies had also suggested a relationship between the two factors. "We could not detect this correlation," says Witte. "It is possible that in previous analyses other factors had blurred the results, including the BMI or conspicuous personality traits that are known to be associated with depression. We accounted for them," said Witte explaining a possible reason for the different results. In addition, the plant-based diet is now more common and more accepted and not anymore restricted to a certain group.The scientists had investigated these connections within the so-called LIFE project, a broad-based study in cooperation with the University Hospital of Leipzig. They determined the personal diets by means of questionnaires in which the participants were asked to fill in how often they had eaten the individual animal products in the last 12 months -- from "several times a day" to "never." The personality traits such as extroversion and neuroticism were assessed by means of a so-called personality inventory (NEOFFI), while depression was assessed by means of the so-called CESD test, a questionnaire that records various symptoms of depression.
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Agriculture & Food
| 2,020 |
June 12, 2020
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https://www.sciencedaily.com/releases/2020/06/200612172202.htm
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Parasites and the microbiome
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Parasite infections are a constant presence for many people who live in tropical regions, particularly in less industrialized areas. These often chronic conditions are at best unpleasant; more seriously, children with parasite diseases that cause diarrhea can die of malnutrition or dehydration.
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In "We found that we could look at someone's microbiome and use it to predict whether someone had a gastrointestinal parasite infection," says Meagan Rubel, who completed her doctorate degree at Penn and is now a postdoc at the University of California, San Diego. "Whether or not it was parasites changing the microbiome or something in the resident microbiota of a person that made them more susceptible to infection, we can't say, but the association was strong."Rubel led the study in collaboration with Penn's Sarah Tishkoff, a Penn Integrates Knowledge Professor in the Perelman School of Medicine and School of Arts and Sciences, and Frederic Bushman, a microbiologist in the medical school. In addition to the microbiome and parasites, the research also examined markers of immune function, dairy digestion, and pathogen infection, a rich dataset.The investigation entailed six months of field work, collecting fecal and blood samples from Mbororo Fulani pastoralists, cattle herders with a diet high in meat and dairy; Baka and Bagyeli rainforest hunter-gatherers, who practice a limited amount of farming but also forage for meat and plant-based foods; and Bantu-speaking agropastoralists, who both grow crops and raise livestock. As a comparison group, the study included data from two groups of people living in urban areas of the United States, with a diet heavier in animal fats, proteins, and processed foods.In the field, the researchers tested for malaria and a number of other pathogens that infect both the blood and gastrointestinal system.Of the 575 people tested in Cameroon, the researchers found nearly 40% were infected with more than one parasite before receiving an antiparasitic treatment, with hunter-gatherers, on average, most likely to be co-infected with multiple parasites. In particular, the team found that four soil-transmitted gut parasites tended to co-occur at a rate much higher than chance: Ascaris lumbricoides, Necator americanus, Trichuris trichiura, and Strongyloides stercoralis, or ANTS."Gut parasites are a global public health concern," says Rubel. "And you tend to see several of these parasites together in resource-poor settings where people may not have access to clinical care, piped water, and soap, so there's more opportunity for them to be transmitted."Back in the lab at Penn, the researchers used genomic sequencing tools to take a snapshot of the participants' gut microbiomes. The composition of the microbiome, they found, could accurately predict a person's country (U.S. or Cameroon) and lifestyle (urban, pastoralist, agropastoralist, or hunter-gatherer). But after these two variables, the presence of ANTS parasites could be predicted with greater accuracy by the microbiome structure than any other variable the research team studied. Taken together, the microbiome could predict the presence of these four gut parasites with roughly 80% accuracy.Infection with these parasites also led to upticks in immune system activation, specifically turning on pathways that promote inflammatory responses. Parasite infection was also associated with a greater likelihood of having bacteria from the order Bacteroidales, which are known to play a role in influencing digestion and immune system function.In a second part of the study, the Penn-led team assessed the relationship between the gut microbiome and milk consumption in the Fulani pastoralist population. Earlier work by Tishkoff and colleagues illuminated how genetic mutations enabling lactose digestion arose in pastoralist communities in Africa, selected through evolution because of the important nutritional benefits of consuming dairy. In looking at the Fulani's microbiomes, they also tended to have an abundance of bacterial genes capable of breaking down galactose, a component of lactose, and fats, compared to other groups. "This enrichment of genes could help you extract more nutrition from the food you eat," Rubel says.The researchers believe their findings, the largest-ever study on the link between gut microbiome composition and parasite infection from sub-Saharan Africa, can open new possibilities for future work. "The kinds of microbiome markers we found could be useful to predict the type of pathogens you have, or to shed light on the interplay between the microbiome and the immune system," says Rubel.Eventually, she adds, more research could even illuminate strategies for purposefully modulating the microbiome to reduce the risk of a parasite infection or minimize the harm it causes to the body.
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Agriculture & Food
| 2,020 |
June 12, 2020
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https://www.sciencedaily.com/releases/2020/06/200612111423.htm
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Plant cell gatekeepers' diversity could be key to better crops
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Scientists have shed new light on how the network of gatekeepers that controls the traffic in and out of plant cells works, which researchers believe is key to develop food crops with bigger yields and greater ability to cope with extreme environments.
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Everything that a plant needs to grow first needs to pass through its cells' membranes, which are guarded by a sieve of microscopic pores called aquaporins."Aquaporins (AQPs) are ancient channel proteins that are found in most organisms, from bacteria to humans. In plants, they are vital for numerous plant processes including, water transport, growth and development, stress responses, root nutrient uptake, and photosynthesis," says former PhD student Annamaria De Rosa from the ARC Centre of Excellence for Translational Photosynthesis (CoETP) at The Australian National University (ANU)."We know that if we are able to manipulate aquaporins, it will open numerous useful applications for agriculture, including improving crop productivity, but first we need to know more about their diversity, evolutionary history and the many functional roles they have inside the plant," Ms De Rosa says.Their research, published this week in the Journal "We described 76 types of these microscopic hour-glass shape channels based on their gene structures, protein composition, location in the plant cell and in the different organs of the plant and their evolutionary origin. These results are extremely important as they will help us to transfer basic research to applied agriculture," says Ms De Rosa, whose PhD project focused on aquaporins."The Centre (CoETP) is really interested in understanding aquaporins because we believe they are a key player in energy conversion through photosynthesis and also control how a plant uses water. That is why we think we can use aquaporins to enhance plant performance and crop resilience to environmental changes," says lead researcher Dr Michael Groszmann from the Research School of Biology and the CoETP at ANU.Aquaporins are found everywhere in the plant, from the roots to flowers, transporting very different molecules in each location, at an astonishing 100 million molecules per second. The configuration of an aquaporin channel determines the substrate it transports and therefore its function, from the transport of water and nutrients from roots to shoots, to stress signalling or seed development."We focused on tobacco because it is a fast-growing model species that allows us to scale from the lab to the field, allowing us to evaluate performance in real-world scenarios. Tobacco is closely related to several important commercial crops, which means we can easily transfer the knowledge we obtain in tobacco to species like tomato and potato. Tobacco itself has own commercial applications and there is a renewed interest in the biofuel and plant-based pharmaceutical sectors," he says."This research is extremely exciting because the diversity of aquaporins in terms of their function and the substrates they transport, mean they have many potential applications for crop improvement ranging from improved salt tolerance, more efficient fertiliser use, improved drought tolerance, and even more effective response to disease infection. They are currently being used in water filtration systems and our results could help to expand these applications. The future of aquaporins is full of possibilities," says Dr Groszmann.This research has been funded by the Australian Research Council (ARC) Centre of Excellence for Translational Photosynthesis (CoETP), led by the Australian National University, which aims to improve the process of photosynthesis to increase the production of major food crops such as sorghum, wheat and rice.
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Agriculture & Food
| 2,020 |
June 11, 2020
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https://www.sciencedaily.com/releases/2020/06/200611151414.htm
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Function of genetic pathway for reproductive fitness in flowering plants
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Small RNAs are key regulators involved in plant growth and development. Two groups of small RNAs are abundant during development of pollen in the anthers -- a critical process for reproductive success. A research collaboration has demonstrated the function of a genetic pathway for anther development, with this pathway proven in 2019 work to be present widely in the flowering plants that evolved over 200 million years ago. The research team was led by Blake Meyers, Ph.D., member, Donald Danforth Plant Science Center and professor, Division of Plant Sciences, University of Missouri, and Virginia Walbot, Ph.D., Professor of Biology, Stanford University. Their findings, "Dicer-like 5deficiency confers temperature-sensitive male sterility in maize" were published in the journal,
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Unexpectedly, their research uncovered an environmentally sensitive male sterile phenotype. By using mutants and knocking out one of the pathways, the research team produced plants that failed to make pollen, but when they lowered the temperature, they found they could recover full male fertility. This ability to turn on or turn off pollen production in different conditions could be useful for seed production. The team could also attribute the function of this pathway in anther development, an observation previously missing but important. These results are important companions to a previously published discovery, which described the evolutionary distribution of the pathway across flowering plants, "24-nt reproductive phasiRNAs are broadly present in angiosperms,"also published in the journal "Putting these two discoveries together, we can understand the role these molecules play is important for full male fertility in maize, plus, the pathway first evolved with flowering plants," said Meyers. "Understanding the genetic mechanisms by which flowers develop is important for improving crop yields and breeding better varieties, particularly for making the high-yielding hybrid crops that support modern agriculture."The research team will continue to work to understand why there is an environmentally-sensitive response to changes in this pathway, and what exactly is the molecular mechanism that leads to this male sterility in the absence of this small RNA pathway. Work in a separately funded project is examining if modulation of this pathway could be used to regulate pollen development in other crops, for the improvement of seed production and crop yield.The authors include co-first authors, Chong Teng, Ph.D., postdoctoral associate in the Meyers lab and Han Zhang, Ph.D. former postdoctoral associate in the Walbot lab. Also contributing were Kun Huang, Ph.D., postdoctoral associate in the Meyers lab, and Reza Hammond, Ph.D., former graduate student in the Meyers lab. The work is funded by the National Science Foundation.
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Agriculture & Food
| 2,020 |
June 11, 2020
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https://www.sciencedaily.com/releases/2020/06/200611094125.htm
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Crop pathogens 'remarkably adaptable'
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Pathogens that attack agricultural crops show remarkable adaptability to new climates and new plant hosts, new research shows.
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Researchers at the Department of Biosciences, University of Exeter studied the temperature preferences and host plant diversity of hundreds of fungi and oomycetes that attack our crops.The researchers found that plant pathogens can specialise on particular temperatures or host plants, or have wide temperature or host ranges.Lead author Professor Dan Bebber, a member of Exeter's Global Systems Institute, said: "Traditionally, scientists have considered species to be specialists or generalists."Generalists are sometimes called 'Jack of all trades, master of none'. Our analyses show that many plant pathogens are 'Jack of some trades, master of others'."Tom Chaloner, an SWBIO DTP PhD student, said: "We have collated the largest dataset on plant pathogen temperature responses, and made this available for the scientific community."Our data allow us to test some of the most fundamental questions in ecology and evolution."For example, we found that temperature preferences are narrower when pathogens are growing within plants, demonstrating the difference between the so-called fundamental niche and the realised niche."The researchers used recently-developed statistical methods to investigate the co-evolution between pathogens and their hosts, showing that pathogens can readily evolve to attack new host plants."In an era of growing global population size, climate change and emerging threats to crop production and food security, our findings will be key to understanding where and when pathogens could strike next," said co-author Professor Sarah Gurr.
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Agriculture & Food
| 2,020 |
June 10, 2020
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https://www.sciencedaily.com/releases/2020/06/200610094051.htm
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Reusing chicken litter shows benefits
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Chicken is the most consumed protein in the United States. According to the National Chicken Council, the U.S. produced more than 9.2 billion broiler chickens in 2019. US consumers spent more than 95 billion dollars on chicken products.
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All these broilers -- chickens raised for meat -- need millions of tons of litter, or bedding material. Reusing chicken litter can save costs. There exists some health and safety concerns though.A new study shows that the environment in reused poultry litter can deter growth of pathogens like Salmonella."When you read or hear that broiler litter is reused to raise multiple flocks of chickens, the typical reaction is that it must be bad for food safety," says Adelumola Oladeinde, a co-author of the recent study. "Our study demonstrates the exact opposite."Oladeinde is a researcher at the USDA's National Poultry Research Center in Athens. He and his colleagues found that 'good' bacteria in used poultry litter can hinder Salmonella growth."It may be worthwhile to invest time and resources to characterize the bacteria in reused litter," says Oladeinde. "We can develop the promising ones into beneficial microbes for better chicken gut health."The study also explored litter characteristics, such as moisture and ammonia levels. These characteristics can dramatically affect the litter microbiome -- the mix of bacteria, fungi, and viruses in litter."Our findings provide new information on the relationship between the physical environment of broiler litter and its microbiome," says Oladeinde. "Management techniques that account for both factors may help reduce Salmonella in chickens."Chicken litter plays a big role in determining broiler health. After a broiler chick gets to a farm, it usually spends the next several weeks pecking and living on litter.In fact, chicks begin to eat litter even before eating from feeding troughs or drinking. The microbiome present in the litter likely become the 'first settlers' in the guts of the chicks."These first microbes play a key role in determining gut health," says Oladeinde. "Therefore, it is critical to determine what a beneficial litter microbiome looks like."The team collected samples of reused poultry litter from the University of Georgia Poultry Research Center. The litter was used to raise three flocks of broiler chickens under conditions like those used in broiler farms. "Each sample represents a unique broiler litter environment," says Oladeinde.In the lab, researchers measured characteristics of the litter samples. Then they added Salmonella to each sample. After that, the samples were tested for levels of Salmonella, other bacteria, and physical characteristics.Within two weeks of adding Salmonella, most samples developed predictable microbiomes. Certain microbes, such as Nocardiopsis bacteria, seemed to reduce growth of Salmonella.That makes sense, according to Oladeinde. Some species of Nocardiopsis bacteria are known to produce antibiotics and toxins. These compounds could be keeping Salmonella levels low in the litter samples.A key aspect of reusing broiler litter is how long to wait before reuse. This waiting period is called litter downtime."For farmers, a shorter downtime will result in growing more birds through the year," says Oladeinde. However, we know little about how downtime affects litter microbiome.Results from the study show that surveying levels of specific bacteria could help determine if litters have had enough downtime. That could be of big help to farmers."Poultry litter is a complex environment to study," says Oladeinde. "We showed that the reused litter after two weeks of downtime had a microbiome that was unfavorable to Salmonella."Oladeinde aims to repeat these experiments with litter from various sources. He also wants to test for multiple Salmonella strains. "These studies will tell us about the underlying mechanisms behind reusing litter and reducing Salmonella," he says.This work was funded by the United States Department of Agriculture, Agricultural Research Service.
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Agriculture & Food
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