Wheatgrass Thinopyrum intermedium is a source of agronomically valuable traits for common wheat. Partial wheat–wheatgrass amphidiploids and lines with wheatgrass chromosome substitutions are extensively used as intermediates in breeding programs. Line Agis 1 (6Agi2/6D) is present in the cultivar Tulaykovskaya 10 pedigree. Wheatgrass chromosome 6Agi2 carries multiple resistance to fungal diseases in various ecogeographical zones. In this work, we studied the transfer of chromosome 6Agi2 in hybrid populations Saratovskaya 29 × skaya 10 (S29 × T10) and Tulaykovskaya 10 × Saratovskaya 29 (T10 × S29). Chromosome 6Agi2 was identif ied by PCRwith chromosome-specif ic primers and by genomic in situ hybridization (GISH). According to molecular data, 6Agi2was transmitted to nearly half of the plants tested in the F2 and F3 generations. A new breeding line 49-14 (2n = 42)with chromosome pair 6Agi2 was isolated and characterized in T10 × S29 F5 by GISH. According to the results ofour f ield experiment in 2020, the line had high productivity traits. The grain weights per plant (10.04 ± 0.93 g) andthe number of grains per plant (259.36 ± 22.49) did not differ signif icantly from the parent varieties. The number ofgrains per spikelet in the main spike was signif icantly higher than in S29 ( p ≤ 0.001) or T10 ( p ≤ 0.05). Plants werecharacterized by the ability to set 3.77 ± 0.1 grains per spikelet, and this trait varied among individuals from 2.93 to4.62. The grain protein content was 17.91 %, and the gluten content, 40.55 %. According to the screening for fungaldisease resistance carried out in the f ield in 2018 and 2020, chromosome 6Agi2 makes plants retain immunity tothe West Siberian population of brown rust and to dominant races of stem rust. It also provides medium resistantand medium susceptible types of response to yellow rust. The possibility of using lines/varieties of bread wheatwith wheatgrass chromosomes 6Agi2 in breeding in order to increase protein content in the grain, to confer resistanceto leaf diseases on plants and to create multif lowered forms is discussed. Wild perennial common wheat relatives of the Thinopyrumgenus are broadly polymorphic. They can be sources ofcommercially valuable traits: resistance to fungal and viraldiseases ,tolerance of saline soils and drought, and high protein contentsin the grain . TheThinopyrum genus includes about 20 species of differentploidies: diploids, allotetraploids, allohexaploids, octoploids,and decaploids . The genetic poolsof two species are in the greatest use: elongate wheatgrassTh. elongatum (Agropyron elongatum) and intermediatewheatgrass Th. intermedium (Ag. glaucum). They becamedonors of genes for resistance to pests: Lr19, Lr24, Lr29,and Lr38 to brown rust; Sr24, Sr25, Sr26, Sr43, and Sr44to stem rust; Pm40 and Pm43 to powdery mildew; Bdv2to barley yellow dwarf virus; and Wsm1 to wheat streakmosaic virus .Viable wheat–wheatgrass hybrids were first obtained byN.V. Tsitsin in 1930–1933. He crossed diploid, tetraploid,and hexaploid wheats to Ag. elongatum and Ag. glaucum and obtained octoploid forms of perennialand ratooning wheats known as intermediate wheat–wheatgrasshybrids, IWWHs . Experiments on wheat hybridization to plants ofthe Thinopyrum genus were also carried out in the UnitedStates, Germany, Canada, and China. Various hybrid formswere obtained and annotated: partial amphiploids; highproteinaddition, substitution, and translocation lines andforms resistant to barley yellow dwarf virus, wheat streakmosaic virus, powdery mildew, yellow rust, brown rust,and stem rust .Partial wheat–wheatgrass amphidiploids are used internationallyfor transferring valuable traits to commonwheat . In Russiatwo groups of common wheat cultivars resistant to fungalpests have been raised via IWWHs at the AgriculturalResearch Institute of the South-East and the Samara ResearchInstitute of Agriculture. In their genomes, wheatchromosome 6D is replaced by chromosome 6Agi fromwheatgrass Th. intermedium. Chromosomes 6Agi1 and6Agi2 are not identical, as they show different C bandingpatterns in Giemsa staining . In theformer case, 6Agi1 was inherited from substitution lineS29-Agro139-M2-2, obtained by crossing spring commonwheat Saratovskaya 29 to IWWH 139, and fromcv. Mnogoletka2. Then wheatgrass addition chromosomesrecombined with each other . The cultivarsraised in Samara inherited wheatgrass chromosome6Agi2 from substitution line Agis 1, obtained by crossingS29 to IWWH 644 .Since 1984, when Tulaykovskaya 5 was enlisted to theState Register of Selection Achievements, varieties withwheatgrass chromosome introgression bred in Samararetain their resistance to brown rust and powdery mildewin various ecogeographical regions of Russia . It has been shown thatthe Lr genes on chromosome 6Agi2 are not allelic to thegenes Lr9, Lr19, Lr24, Lr29, or Lr47, and the type of responseto inoculation with Puccinia triticina Eriks. isolatesconfirms their not being allelic to Lr19 or Lr38 . Testing of F2 and F3 hybrids of susceptiblevarieties with Tulaykovskaya 10 for brown rust resistanceshows that chromosome 6Agi2 houses a locus for resistanceto the West Siberian brown rust race .However, the copy number of resistance genes on 6Agi2is still unknown. The loci have not been mapped on thechromosome either.Molecular and cytogenetic markers are designed fordetectionof wheatgrass genetic material in the commonwheat genome . There are molecularmarkers specific to the Th. intermedium genome: simple sequencerepeats (SSRs) , markers designed on the base of expressed sequences (ESTs), and specificlocus amplified fragments (SLAFs) .There are several RFLP , SCAR, and ISSR  markersfor Pseudoroegneria spicata (St genome), designedfor identification of particular chromosomes of the St genome.The correspondence of wheatgrass chromosomes tohomoelogical common wheat groups is tested with uniquegene markers based on PCR (PLUG markers)  and SNP markers . Salina et al. (2016) designed markersspecific to the long and short arms of Th. intermediumchromosome 6Agi2Varieties bred in Samara are used in Russian breedingprograms . Thegoal of this work was to obtain breeding material with introgressedwheatgrass chromosome, test its commerciallysignificant indices, and investigate the transfer of Th. intermediumchromosome 6Agi2 present in cv. Tulaykovskaya10 by the example of a hybrid population with wheatcultivar Saratovskaya 29, which is a gold standard of grainquality. DNA markers specific to the long and short armsof 6Agi2 and genomic in situ hybridization (GISH) wereused to identify the chromosome.Plants. Experiments were conducted with spring commonwheat varieties Saratovskaya 29 (S29) and Tulaykovskaya10 (T10) and with their hybrids S29 × T10  and T10 × S29 (generations F2–F6). The hybridgenerations were obtained by self-pollination of F1 hybrids.Varieties S29 and T10 belong to the mid-season group.Saratovskaya 29 is highly susceptible to leaf diseases. Tulaykovskaya10 is immune to brown leaf rust and mediumsensitiveto powdery mildew (https://samniish.ru/pshenicamyagkaya-yarovaya-sort-tulajkovskaya-10.html).Hybrids S29 × T10, generations F2 and F3, and T10 × S29,generations F2, F3 and F5, were grown in a hydroponicgreenhouse of the Laboratory of Artificial Plant Growth,Institute of Cytology and Genetics, Novosibirsk, in theautumn of 2017 and in the springs of 2019 and 2020,respectively. The temperature schedule was 22 °C in thedaytime and 16 °C at night. The light/dark schedule was16:8 h. Hybrid generations T10 × S29 F4 and F6 were grownin the field in the Moshkovo raion of the Novosibirsk oblastin the summers of 2018 and 2020, respectively; localitycoordinates 55.14° N and 83.63° E.Fluorescence in situ hybridization (FISH). Mitoticchromosome slides for FISH were prepared as in Ivanova etal. (2019). Use was made of the Aegilops tauschii pAet6- 09probe specific to chromosome centromeric repeatsofrice, wheat, rye, and barley  andwheatgrass genomic DNA isolated from Th. intermediumplants. A DNA sample of the pAet6-09 repeat was kindlyprovided by Dr. A. Lukaszewski . All slides were examinedunderan Axio Imager M1 microscope .Images were captured with a ProgRes MF camera in the Shared Access Center for MicroscopyAnalysis of Biologic Objects, Siberian Branch ofthe RAS, and processed with Adobe Photoshop CS2.Plant DNA isolation. DNA was isolated from youngleaves of hybrids and control plants with a Genomic DNAPurification Kit  accordingto manufacturer’s recommendations.PCR analysis. DNA samples were analyzed with primersMF2/MR1r2 (amplicon size 347 bp) to the long armof chromosome 6Agi2L of Th. intermedium, Te6HS476(amplicon size 200 bp) to the short arm of chromosome6Agi2S of Th. intermedium, and MF2/MR4 (ampliconsize 328 bp) to the long arm of chromosome 6DL. Theprimershad been designed at the Laboratory of Plant MolecularGenetics and Cytogenetics, Institute of Cytologyand Genetics . PCR was carried outin a Bio-Rad T-100 Thermal Cycler. The products wereresolved in 1.5 % agarose gel with ethidium bromide andvisualized with a Gel Doc XR+ gel documentation system.Assessment of commercially valuable traits. TheT10 × S29 F4 progeny selected with molecular markers wastested for resistance to brown rust Puccinia triticina Eriks.and stem rust P. graminis Pers. in field experiments in2018. The F6 progeny selected by molecular cytologicalanalysis was tested for resistance to brown rust P. triticinaEriks., stem rust P. graminis Pers., and yellow rustP. glumarum Eriks.et Henn. in the field in 2020. The followingparameterswere recorded in generation F6 selectedby molecular and cytological methods in the field in 2000:the sprouting–flowering interval, plant height, productivetillering, main spike length, number of spikelets in the mainspike, number of grains in the main spike, grain weight ofthe main spike, number of grains per spikelet in the mainspike, grain number per plant, grain weight per plant,1000 grain weight, and contents of protein and gluten inthe grain. Grains were sown on May 9, 2020, in plots of70 cm in width, 15 grains per row, and 25-cm intervalsbetween rowsThe degree of injury by fungal pests was assessed accordingto the CIMMYT scale .The contents of protein and gluten were measured with aninfrared OmegAnalyzer G . The timefrom the mass-scale appearance of sprouts till the first appearanceof yellow anthers in middle spikelets of spikeswas taken to be the sprouting–flowering interval. Floweringdates were recorded in individual spikes. The significanceof differences between two mean values of two sampleswas assessed by Student’s t testIdentification of wheatgrass chromosome 6Agi2in generations F2–3 of the S29 × T10 and T10 × S29 hybridswith chromosome-specific primersChromosomes 6Agi2 of wheatgrass and 6D of wheat werepresent in the F1 of S29 × T10 and T10 × S29 in the univalentstate. Therefore, their presence or absence in DNAsamples from generation F2 was tested by PCR with primersspecific to the wheatgrass chromosome. We tested 116and 45 DNA samples from F2 S29 × T10 and T10 × S29,respectively, and found samples with the absence of amplificationwith two primer pairs for the short and longarms of chromosome 6Agi2 and with amplification of themarker to chromosome 6D. Thus, there were no 6Agi2/6Dsubstitution in these samples, designated as wheat (w) type.The presence of chromosome 6D was also proven insamples with amplification of markers to either long orshort arm, being indicative of the presence of telocentrics. Altogether, 12 telocentrics forthe long arm and 29 telocentrics for the short arm were detected in samples of generations F2 and F3, and the ratioof telocentrics for the short and long arm depended significantlyon the cross direction. Telocentrics for the long armwere very rare in the T10 × S29 cross.The presence of amplification fragments with two markersto the short and long arms pointed to the presenceof the whole chromosome 6Agi2. With regard to the presenceor absence of chromosome 6D, we suggest eitherfull 6Agi2/6D substitution (Ag type) or the heterozygousstate of the chromosome in the samples (H type).For further analysis, plants with amplification of markersto the short and long arm of the wheatgrass chromosomewere selected.Karyotyping of generation F5 of T10 × S29 hybridsTo verify the presence of one or two wheatgrass chromosomesin chromosome sets and to confirm stable inheritanceof the substitution, we performed GISH of mitotic chromosomesat various self-pollination stages. The analysisof plants bearing substitutions according to PCR revealed42 chromosomes, of which two were whole wheatgrasschromosomes . Their long arms housed a largesubtelomeric heterochromatin block, which is consistentwith the locations of Giemsa C bands on chromosome6Agi2 in Tulaykovskaya 10 . Thecentromere-specific pAet6‑09 repeat located on wheatgrasschromosomes showed weak signals, to demonstrate thepoor hybridization of the repeat to centromeric DNA ofwheatgrass chromosomes.In situ hybridization confirmed the stable inheritance ofthe 6Agi2/6D substitution through generations.Commercially valuable traitsin T10 × S29 generations F5 and F6Tulaykovskaya 10 is present in the pedigrees of manymoderncommon wheat varieties. Its use in the breedingof new forms is based on its locus for brown leaf rustresistance, mapped on wheatgrass chromosome 6Agi2. Inspite of the replacement of chromosome 6D by alien chromosome6Agi2, the variety shows high grain yield, droughttolerance,and good baking quality (https://samniish.ru/pshenica-myagkaya-yarovaya-sort-tulajkovskaya-10.html).Three lines were raised from F4 plants of T10 × S29 withidentified wheatgrass chromosomes: 33-2, 34-1, and 35-45.Analysis of the performance of T10, S29, and T10 × S29F5 lines grown in a hydroponic greenhouse showed thatall the lines significantly outperformed T10 in all indices(Table 2). As compared to S29, the lines did not differ inproductive tillering; lines 34-1 an 35-45 did not differ ingrain number per plant or grain weight per plant; and inline 33-2, these indices were significantly lower. None ofthe lines outperformed S29 in 1000 grain weight; this indexwas significantly lower.We selected the most productive plants of generation F5of line 35-45 to analyze performance indices and the durationof the sprouting–flowering interval in plants grown inthe field in 2020. Thus, daughter line 49-14 was selectedfrom the chosen segregating line 35-45.Phenological observations revealed the shortest sprouting–flowering interval in line 49-14 (50.6 days), and in S29and T10 it was one day longer. The flowering durations inthe main spikes of individual plants were 11 days in 49-14,10 days in T10, and 9 days in S29.Comparison of performance indices in 49-14, S29, andT10 revealed no difference in main spike length, grainweight in the main spike, grain weight per plant, or grainnumber per plant (Table 3). Plants of line 49-14 weresignificantly taller than T10 but did not differ in height from S29. Productive tillering and main spike density in49-14 showed significant ( p ≤ 0.05) differences from thecultivars. The number of grains in the main spike in 49-14was significantly greater than in S29 ( р ≤ 0.001) or T10( р ≤ 0.05).The number of grains per spikelet in the main spike ofline 49-14 was significantly higher than in S29 ( p ≤ 0.001)or T10 ( p ≤ 0.05). Line 49-14 set 3.77 ± 0.1 grains perspikelet on the average, and this trait varied among individualplants from 2.93 to 4.62 . The1000 grain weights in line 49-14 and T10 were significantly( р ≤ 0.001) lower than in S29.Grain quality analysis showed that S29, T10, and 49- 14had high contents of protein and gluten (see Table 3),characteristic of strong wheats. Grain quality in 49-14 wascomparable with S29 and T10.Screening of generations F4 and F6 of the T10 × S29 crossfor resistance to fungal pathogensThe resistance of plants to brown rust and stem rust agentswas tested in the field in 2018 and 2020. Field resistanceto powdery mildew was not tested in those years, becauseweather conditions were unfavorable for the agent, asseen from the fact that the susceptible variety S29 wasnot injured.In tests of the resistance to the Siberian population ofthe brown rust agent P. triticina conducted in 2018, S29demonstrated the S (susceptibility) type of response, scoring4 with about 100 % damage of leaf surface .Tulaykovskaya 10 and F4 plants of T10 × S29 showed theimmune type without P. triticina pustules .The hybrids tested and parental varieties produced aspecific response to stem rust. Plants of S29, T10, andF4 T10 × S29 showed generally the immune response exceptfor a single case. One of the F4 plants showed a specific typeof interaction with the pathogen: occasional uredial pustuleswithout chlorosis (5S) . In practice, thedetected local but pronounced syndrome is interpreted asa sign of a rare virulent fungus race in the local population. As reported by Skolotneva et al.(2020), the stem rust population in the Novosibirsk oblastis highly heterogeneous, as it is formed by southern andwestern migrants.No signs of fungal diseases were detected in plants ofthe cultivars and line 49-14 at the stages of tillering andflowering in the field in 2020. Tests for plant resistanceto the brown rust population at the milky ripeness stageshowed type S (susceptibility) response in S29 plants, score 4 with about 100 % leaf damage, whereasT10 and 49-14 demonstrated the immune response with noP. triticina pustules .At the milky ripeness stage, on August 2–5, the start ofdamage of S29, T10, and 49-14 by the yellow rust agentP. striiformis was noted. The percentage of leaf area injury in S29 was 50 to 75 , corresponding to mediumsusceptibility (MS).Plants of T10 and 49-14 showed medium resistance(MR) and medium susceptibility (MS) to the yellow rustagent. The percentage of leaf area injury was 5 to 40, withchlorotic zones .No damage by stem rust was seen in plants of S29, T10,or 49-14 in the summer of 2020.Thus, the results of screening for resistance to a varietyof plant pathogens conducted in the field in different yearsindicate that chromosome 6Agi2 retains the immunity ofplants to the West Siberian brown rust population and immunityto dominant stem rust races. It also supports themedium resistant and medium susceptible types of responseto yellow rust agents.Breeding line 49-14 (2n = 42) was isolated from generationF5 of intervarietal hybrids T10 × S29, with introgressionof a pair of wheatgrass chromosomes 6Agi2. It showshigh performance indices and immunity to West Siberianpopulationsof brown rust agents. The response of 49-14plants to the yellow rust agent varies from medium resistanceto medium susceptibility,probably because of thedifference in aggressiveness among the agent races. Stemrust injury was noted in only one plant and was interpretedas immunity to dominant stem rust races.Previously, it was demonstrated that the genetic materialof chromosome 6Agi2 in common wheat varietiesTulaykovskaya 5, Tulaykovskaya 10, Tulaykovskaya zolotistaya,Tulaykovskaya 100, and Volgouralskaya retains theresistance to brown rust populations typical of the Lowerand Middle Volga regions, Central and Ural regions, andWest Siberia . The damageof Tulaykovskaya 10 by brown rust in infection nurseriesof the Central Chernozem region reached 22 %, and thevariety was assigned to group II of epidemic resistance(moderately resistant ER II) . In Tatarstan,the damage of Tulaykovskaya 10 by stem rust was assessedas 5–10 % on the average, and the damage by powdery mildewscored 6; the type of response to brown rust remainedimmune . The susceptibility ofT10 to the powdery mildew population of the West Siberianregion was assessed as resistance. A genome-wideassociation search (GWAS) mapped the Pm6Agi2 gene onthe long arm of wheatgrass chromosome 6Agi2, and thisgene imparts resistance to the powdery mildew agent . In experiments in the Middle Volga region,T10 showed immunity to brown rust and medium resistance(20 % injury) to stem rust, yellow rust, and powdery mildew. Thus, T10 retains its immunity tobrown rust populations in various ecogeographical regions.It is medium susceptible to stem and yellow rusts but showsdiverse responses to the powdery mildew agent.The substitution of wheatgrass chromosome 6Agi2 for6D does not impair grain yield, grain quality, or droughttolerance ,although in some cases of using T10 as a resistance genedonor, plants with lower productive tillering and 1000 grainweight appeared among the offspring with chromosome6Agi2 . The contents of protein andgluten in line 49-14 were about the same as in S29 orT10, corresponding to the grain quality of strong wheats. Line 49-14 lagged behindthe parental varieties in productive tillering (S29), numberof spikelets in the main spike (T10), and 1000 grainweight (S29). In spite of lower productive tillering, fewerspikelets in the main spike, and lower 1000 grain weight,the indices grain weight per plant and grain number perplant in line 49-14 did not differ significantly from theparental varieties owing to the significantly higher grainnumber per spikelet in the main spike of 49-14 than inS29 ( р ≤ 0.001) or T10 ( p ≤ 0.05). Plants of 49-14 set3.77 ± 0.1 grains per spikelet, the range of variation inindividual plants being 2.93–4.62, and up to 6 grains wereset in spikelets of the middle spike part. Spikelets werefan-shaped . This shape is a specific sign ofmultiflowered spikelets in wheat .Although common wheat has multiflowered spikelets,most of them set two or three grains. As the potential offorming more grains in wheat exceeds the actual yield byfar, many studies are dedicated to seeking tools to controlthis process. The genetic and physiological groundsof breeding for more grains in spikes and spikelets and,ultimately, more grains per unit area are extensively investigated. Analysis of thereproductive developmental stages of spikes, spikelets,florets, and grains, as well as of their genetic regulation, isthe best way to understand the formation of the trait ‘grainnumber and spike fertility’. The ‘grain number per spikelet’trait depends on the initiation of floret primordia, then onfloret survival at the next stage, and then on their efficientpollination. Normally, up to 12 floret primordia form atthe white anther stage, but later up to 60 % of the floretsmay remain underdeveloped . Thisapplies especially to apical (uppermost) florets of a spikelet.As reported by Kuperman (1969), the growth rates ofthe two lowest and upper floret apices are nonuniform atorganogenesis stage V; a spikelet may have up to five, lessoften, to seven florets. Lower florets very quickly formprimordia of generative organs, stamens, and the pistil.A delay in organ formation is observed in the third and,particularly, fourth, fifth, and subsequent florets. Pistilsmost often remain underdeveloped in the uppermost florets.Chromosomes 4A, 5A, 6A, 7A, 2B, 5B, 7B, and 7D bear QTLs responsible for the trait ‘number of floret primordiaper spikelet’ . Also, the correlation andcluster analyses performed in the same study infer thatthe number of grains per spikelet does not depend on themaximum number of floret primordia per spikelet . Hence, the number of grains in a spikelet isdetermined by the fertility of each floret .A QTL responsible for greater numbers of grains perspikelet was detected on the long arm of chromosome 2Ain GWAS of European common wheat varieties . Further studies of this locus mapped the GrainNumber Increase 1 (GNI1) gene, encoding a transcriptionfactor with the HDZip1 homeodomain. Its mutationcontributes much to greater numbers of fertile florets dueto upper florets of the spikelet . Supposedly,GNI1 was formed by gene duplication in wheatevolution, and its mutations were selected in domestication,as they increased the number of fertile florets, and,consequently, grains. Transcription factor ARGONAUTE1d(AGO1d ) also affects the grain number in the spikes ofcommon and durum wheats . AGO1dis important for the development of anthers and pollenat early developmental stages of wheat. Its malfunctionshortens the spike, reduces anther size, decreases pollenfertility, and thereby decreases the number of grains in thespike .The manifestation of traits in a plant is cumulatively affectedby the genotype, ambient conditions, and farmingtechniques. All these factors greatly influence quantitativetraits, including yield components . The day/night regime and solarspectrum are particularly important ambient factors atorganogenesis stages V and VI . Lowerintensities of the red and infrared radiation reduce thenumber of fertile florets, number of grains per plant, and1000 grain weight . The combinationsof environmental factors required for each developmentalstage stem from the conditions under which the species,varieties, and cultivars formed. With regard to their physiologicaldevelopmental features, cultivars S29 and T10belong to the Volga steppe and forest-steppe agroecologicalgroups, respectively, or morphophysiological type II  (https://samniish.ru/yarovaya_myagkaya_pshenica.html). Such varieties utilize mainly winter andearly spring precipitation in regions with water shortagein the second half of summer; that is, they are tolerant ofsummer drought. Cultivars bred in West Siberia belongto morphophysiological type V. The ecotype of Siberianforest-steppe wheats is determined by the climate: cold anddry April, May, and the first half of June; relatively ampleprecipitation in the second half of summer (July), and coldtemperatures in August. The delay in organogenesis stage Vallows much better use of late summer precipitation forthe formation of large spikes and multiflowered spikelets.Owing to developmental physiological features and highdrought tolerance, varieties of morphophysiological type IIcan be grown in steppe and forest-steppe regions of WestSiberia . Thus, the genotypes of S29 andT10 are environmentally flexible. In the climate of WestSiberian forest-steppe, they synchronize the metamericgrowth of spikelets to develop four, five, or more normalflorets in a spikelet.The genetic material of crested wheatgrass Agropyroncristatum is also beneficial for yield components. Additionlines with chromosome 6P of Ag. cristatum and,particularly, substitution lines 6P/6D show high productivetillering and significantly greater grain numbers inspikes and spikelets: up to 4.5 grains per spikelet . It has been inferred thatchromosome 6P houses genes controlling the numbers offlorets and grains in a spike and spikelet .Conceivably, chromosome 6Agi2 of Th. intermedium bearsgene(s) controlling the synchronous metameric growth ofspikelets in T10, whereas the additive manifestation of thetrait ‘grain number per spikelet’ is observed in line 49-14(T10 × S29), where up to six normal florets develop ina spikeletSakuma et al., 2019) are means for improvingwheat grain yield.The authors declare no conflict of interest.Arbuzova V.S., Dobrovolskaya O.B., Martinek P., Chumanova E.V.,Efremova T.T. Inheritance of signs of “many-flowered” commonwheat and evaluation of productivity of the spike of F2 hybrids.Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journalof Geneticsand Breeding. 2016;20(3):355-363. DOI 10.18699/VJ16.125. (in Russian)Askhadullin D.F., Askhadullin D.F., Vasilova N.Z., Khusainova I.I.,Tazutdinova M.R. A variety in the spring wheat protection systemfrom leafy diseases. Vestnik Kazanskogo GAU = Vestnik ofthe Kazan State Agrarian University. 2019;3(54):10-14. DOI10.12737/article_5db8423bb4f997.64890554. (in Russian)Ayala-Navarrete L., Thompson N., Ohm H., Anderson J. Molecularmarkers show a complex mosaic pattern of wheat-Thinopyrum intermediumtranslocations carrying resistance to YDV. Theor. Appl.Genet. 2010;121:961-970. DOI 10.1007/s00122-010-1365-y.Bao Y., Wu X., Zhang C., Li X., He F., Qi X., Wang H. Chromosomalconstitutions and reactions to powdery mildew and striperust of four novel wheat-Thinopyrum intermedium partial amphiploids.J. Genet. Genomics. 2014;41(12):663-666. DOI 10.1016/j.jgg.2014.11.003.Bhusal N., Sarial A.K., Sharma P., Sareen S. Mapping QTLs for grainyield components in wheat under heat stress. PLoS One. 2017;12(12):e0189594. DOI 10.1371/journal.pone.0189594.Chang Z.-J., Zhang X.-J., Yang Z.-J., Zhan H.-X., Li X., Liu C.,Zhang C.-Z. Characterization of a partial wheat-Thinopyrumintermedium amphiploid and its reaction to fungal diseases ofwheat. Hereditas. 2010;147(6):304-312. DOI 10.1111/j.1601-5223.2010.02156.x.Cseh A., Yang C., Hubbart-Edwards S., Scholefield D., Ashling S.S.,Burridge A.J., Wilkinson P.A., King I.P., King J., Grewal S. Developmentand validation of an exome-based SNP marker setfor identification of the St, Jr and Jvs genomes of Thinopyrumintermedium in a wheat background. Theor. Appl. Genet. 2019;132:1555-1570. DOI 10.1007/s00122-019-03300-9.Cui F., Ding A., Li J., Zhao C., Wang L., Wang X., Qi X., Li X.,Li G., Gao J., Wang H. QTL detection of seven spike-relatedtraits and their genetic correlations in wheat using two related RILpopulations. Euphytica.2012;186:177-192. DOI 10.1007/s10681-011-0550-7.Danilova T.V., Zhang G., Liu W., Friebe B., Gill B.S. Homoeologousrecombination-based transfer and molecular cytogenetic mappingof a wheat streak mosaic virus and Triticum mosaic virusresistance gene Wsm3 from Thinopyrum intermedium to wheat.Theor. Appl. Genet. 2017;130(3):549-556. DOI 10.1007/s00122-016-2834-8.Davoyan R.O., Bebyakina I.V., Davoyan E.R., Zinchenco A.N., ZubanovaY.S., Mikov D.S. Introgression of common wheat lineswith genetic material of Agropyron glaucum. Vavilovskii ZhurnalGenetiki i Selektsii = Vavilov Journal of Genetics and Breeding.2015;19(1):83-90. DOI 10.18699/VJ15.010. (in Russian)Fedak G., Han F. Characterization of derivatives from wheat-Thinopyrumwide crosses. Cytogenet. Genome Res. 2005;109:360-367.DOI 10.1159/000082420.Feng N., Song G., Guan J., Chen K., Jia M., Huang D., Wu J.,Zhang L., Kong X., Geng S., Liu J., Li A., Mao L. Transcriptomeprofiling of wheat inflorescence development from spikeletinitiation to floral patterning identified stage-specific regulatorygenes. Plant Physiol. 2017;174(3):1779-1794. DOI 10.1104/pp.17.00310.Filatova E.V., Syukov V.V., Anisimkina N.V. Influence of the T-5translocation from wheat grass on the protein fractional structureof spring bread wheat. Agrarnyy Vestnik Yugo-Vostoka = AgrarianHerald of the Southeast. 2010;4:15-17. (in Russian)Friebe B., Jiang J., Raupp W.J., McIntosh R.A., Gill B.S. Characterizationof wheat-alien translocations conferring resistance todiseases and pests: current status. Euphytica. 1996;91:59-87.Fu S., Lv Z., Qi B., Guo X., Li J., Liu B., Han F. Molecular cytogeneticcharacterization of wheat-Thinopyrum elongatum addition,substitution and translocation lines with a novel source of resistanceto wheat fusarium head blight. J. Genet. Genomics. 2012;39:103-110. DOI 10.1016/j.jgg.2011.11.008Guo Z., Chen D., Alqudah A.M., Röder M.S., Ganal M.W., SchnurbuschT. Genome-wide association analyses of 54 traits identifiedmultiple loci for the determination of floret fertility in wheat. NewPhytol. 2017;214:257-270. DOI 10.1111/nph.14342.Guo Z., Slafer G.A., Schnurbusch T. Genotypic variation in spikefertilitytraits and ovary size as determinants of floret and grainsurvival rate in wheat. J. Exp. Bot. 2016;67:4221-4230. DOI10.1093/jxb/erw200.Guo Z., Zhao Y., Röder M.S., Reif J.C., Ganal M.W., Chen D.,Schnurbusch T. Manipulation and prediction of spike morphologytraits for the improvement of grain yield in wheat. Sci. Rep. 2018;8:14435. DOI 10.1038/s41598-018-31977-3.Han F., Liu B., Fedak G., Liu Z. Genomic constitution and variationin five partial amphiploids of wheat-Thinopyrum intermediumas revealed by GISH, multicolor GISH and seed storage proteinanalysis. Theor. Appl. Genet. 2004;109:1070-1076. DOI 10.1007/s00122-004-1720-y.Han H., Bai L., Su J., Zhang J., Song L., Gao A., Yang X., Li X.,Liu W., Li L. Genetic rearrangements of six wheat-Agropyroncristatum 6P addition lines revealed by molecular markers. PLoSOne. 2014;9(3):e91066. DOI 10.1371/journal.pone.0091066.Hu J., Wang X., Zhang G., Jiang P., Chen W., Hao Y., Ma X., Xu S.,Jia J., Kong L., Wang H. QTL mapping for yield-related traits inwheat based on four RIL populations. Theor. Appl. Genet. 2020;133:917-933. DOI 10.1007/s00122-019-03515-wHu L.J., Li G.R., Zeng Z.X., Chang Z.J., Liu C., Zhou J.P., Yang Z.J.Molecular cytogenetic identification of a new wheat-Thinopyrumsubstitution line with stripe rust resistance. Euphytica. 2011;177:169-177. DOI 10.1007/s10681-010-0216-x.Hu L., Li G., Zhan H., Liu C., Yang Z. New St-chromosome-specificmolecular markers for identifying wheat-Thinopyrum intermediumderivative lines. J. Genet. 2014;93:69-74. DOI 10.1007/s12041-012-0158-2.Ishikawa G., Nakamura T., Ashida T., Saito M., Nasuda S., Endo T.R.,Wu J., Matsumoto T. Localization of anchor loci representing fivehundred annotated rice genes to wheat chromosomes using PLUGmarkers. Theor. Appl. Genet. 2009;118:499-514. DOI 10.1007/s00122-008-0916-y.Ivanova Yu.N., Solovey L.A., Loginova D.B., Miroshnikova E.E.,Dubovets N.I., Silkova O.G. The creation and characterizationof the bread wheat line with a centric translocation T2DL.2RL.VavilovskiiZhurnal Genetiki i Selektsii = Vavilov Journal of Geneticsand Breeding. 2019;23(7):846-855. DOI 10.18699/VJ19.558. (in Russian)Jiang J., Friebe B., Gill B.S. Recent advances in alien gene transfer inwheat. Euphytica. 1993;73:199-212. DOI 10.1007/BF00036700.Koyshybaev M., Shamanin V.P., Morgunov A.I. Wheat Screeningfor Resistance to Major Diseases: Guidelines. Ankara: FAO-SEKPubl., 2014. (in Russian)Kroupin P., Kuznetsova V., Romanov D., Kocheshkova A., KarlovG., Dang T.X., Khuat T.M.L., Kirov I., Alexandrov O., PolkhovskiyA., Razumova O., Divashuk M. Pipeline for the rapiddevelopment of cytogenetic markers using genomic data of relatedspecies. Genes. 2019;10(2):113. DOI 10.3390/genes10020113.Krupin P.Yu., Divashuk M.G., Belov V.I., Zhemchuzhina A.I., KovalenkoE.D., Upelniek V.P., Karlov G.I. Investigation of intermediarywheat-Agropyron hybrids on resistance to leaf rust. Sel’skokhozyaistvennayaBiologiya = Agricultural Biology. 2013;48(1):68-73. DOI 10.15389/agrobiology.2013.1.68eng.Krupin P.Yu., Divashuk M.G., Karlov G.I. Gene resources of perennialwild cereals involved in breeding to improve wheat crop (review).Sel’skokhozyaistvennaya Biologiya = Agricultural Biology. 2019;54(3):409-425. DOI 10.15389/agrobiology.2019.3.409eng.Kuperman F.M. Physiology of the development, growth and organogenesisof wheat. In: Henkel P.A. (Ed.). Wheat Physiology.IV. Physiologyof Agricultural Plants. Moscow: Moscow UniversityPubl., 1969;7-193. (in Russian)Leonova I.N. Influence of alien genetic material on the manifestationof agronomically important traits of common wheat (T. aestivumL.). Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journalof Geneticsand Breeding. 2018;22(3):321-328. DOI 10.18699/VJ18.367. (in Russian)Leonova I.N. Influence of alien genetic material on the manifestationof agronomically important traits of common wheat (T. aestivumL.). Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journalof Geneticsand Breeding. 2018;22(3):321-328. DOI 10.18699/VJ18.367. (in Russian)Leonova I.N. Genome-wide association study of powdery mildewresistance in Russian spring wheat varieties (T. aestivum L.).Russ. J. Genet. 2019;55(11):1360-1374. DOI 10.1134/S1022795419110085.Leonova I.N., Stasyuk A.I., Skolotneva E.S., Salina E.A. Enhancementof leaf rust resistance of Siberian winter wheat varieties bymarker-assisted selection. Cereal Res. Commun. 2017;45(4):621-632. DOI 10.1556/0806.45.2017.048.Li D., Long D., Li T., Wu Y., Wang Y., Zeng J., Xu L., Fan X., Sha L.,Zhang H., Zhou Y., Kang H. Cytogenetics and stripe rust resistanceof wheat-Thinopyrum elongatum hybrid derivatives. Mol.Cytogenet.2018;11:16. DOI 10.1186/s13039-018-0366-4.Li G., Wang H., Lang T., Li J., La S., Yang E., Yang Z. New molecularmarkers and cytogenetic probes enable chromosome identificationof wheat-Thinopyrum intermedium introgression lines for improvingprotein and gluten contents. Planta. 2016;244:865-876.DOI 10.1007/s00425-016-2554-yLi H., Wang X. Thinopyrum ponticum and Th. intermedium: the promisingsource of resistance to fungal and viral diseases of wheat.J. Genet. Genomics. 2009;36(9):557-565. DOI 10.1016/S1673-8527(08)60147-2.Liu C., Yang Z.J., Li G.R., Feng J., Zhou J.P., Ren Z.L. A discussionon genetic relationship in genome between Thinopyrum andDasypyrum. Chinese High Tech. Lett. 2007;17:295-300.Ma H., Zhang J., Zhang J., Zhou S., Han H., Liu W., Yang X., Li X.,Li L. Development of P genome-specific SNPs and their applicationin tracing Agropyron cristatum introgressions in commonwheat. Crop J. 2019;7(2):151-162. DOI 10.1016/j.cj.2018.07.003.Martinek P., Watanabe N., Peng Z.S. Gene resources of wheat (Triticumaestivum L.) with different arrangement of spikelets in spike.In: 7th International Wheat Conference, Mar del Plata, 2005.Martynov S.P., Dobrotvorskaya T.V., Krupnov V.A. Genealogicalanalysisof the use of two wheatgrass (Agropyron) species incommonwheat (Triticum aestivum L.) breeding for disease resistance.Russ. J. Genet. 2016;52(2):154-163. DOI 10.1134/S1022795416020071.Philipp N., Weichert H., Bohra U., Weschke W., Schulthess A.W.,WeberH. Grain number and grain yield distribution along thespike remain stable despite breeding for high yield in winterwheat. PLoS One. 2018;13(10):e0205452. DOI 10.1371/journal.pone.0205452.Piskarev V.V., Boyko N.I., Kondratieva I.V. Sources of agronomicallyimportant traits for breeding of soft spring wheat (Triticum aestivumL.) in the forest steppe of Novosibirsk region. VavilovskiiZhurnal Genetiki i Selektsii = Vavilov Journal of Genetics andBreeding. 2016;20(3):277-285. DOI 10.18699/VJ16.166. (in Russian)Plakhotnik V.V., Zeleneva Yu.V., Sudnikova V.P. Sources and highperformance donors for spring wheat selection to increase resistanceto stress factors of environment. Voprosy Sovremennoj Naukii Praktiki.Universitet imeni V.I. Vernadskogo = Problems ofContemporary Science and Practice. Vernadsky University. 2014;1(50):109-113. (in Russian)Roelfs A.P., Singh R.P., Saari E.E. Rust Diseases of Wheat: Conceptsand Methods of Disease Management. Mexico: CIMMYT, 1992Sakuma S., Golan G., Guo Z., Ogawa T., Tagiri A., Sugimoto K.,BernhardtN., Brassac J., Mascher M., Hensel G., Ohnishi S.,Jinno H., Yamashita Y., Ayalon I., Peleg Z., Schnurbush T., KomatsudaT. Unleashing floret fertility in wheat through the mutationof a homeobox gene. Proc. Natl. Acad. Sci. USA. 2019;116(11):5182-5187. DOI 10.1073/pnas.1815465116Salina E.A., Adonina I.G., Badaeva E.D., Kroupin P.Yu., Stasyuk A.I.,Leonova I.N., Shishkina A.A., Divashuk M.G., Starikova E.V.,Khuat T.M.L., Syukov V.V., Karlov G.I. A Thinopyrum intermediumchromosome in bread wheat cultivars as a source of genesconferring resistance to fungal diseases. Euphytica. 2015;204:91-101. DOI 10.1007/s10681-014-1344-5.Salina E.A., Leonova I.N., Shcherban A.B., Stasyuk A.I. Patent RU2598275 C1. Method of creating lines of winter soft wheat withcomplex resistance to brown and stem rust and powdery mildew. Date of filing:29.07.2015. Date of publication: 20.09.2016. Bull. No. 26. (inRussian)Sibikeev S.N., Badaeva E.D., Gultyaeva E.I., Druzhin A.E.,ShishkinaA.A., Dragovich A.Yu., Kroupin P.Yu., Karlov G.I.,Thi Mai Khuat, Divashuk M.G. Comparative analysis of Agropyronintermedium (Host) Beauv 6Agi and 6Agi2 chromosomes inbread wheat cultivars and lines with wheat–wheatgrass substitutions.Russ. J. Genet. 2017;53(3):314-324. DOI 10.1134/S1022795417030115.Sinigovets M.E. Transferring wheatgrass rust resistance to wheat byadding and replacing chromosomes. Genetika = Genetics (Moscow).1976;12(9):13-20. (in Russian)Sinigovets M.E. Cytogenetic fundamentals of using wheatgrass inwheat improvement. Dr. Biol. Sci. Diss. Bol’shie Vyazemy, 1988.OD 71 89-3/185. Available at: https://search.rsl.ru/ru/record/01008509447. (in Russian)Skolotneva E.S., Kelbin V.N., Morgunov A.I., Boiko N.I., ShamaninV.P., Salina Е.А. Races composition of the Novosibirsk populationof Puccinia graminis f. sp. tritici. Mikologiya i Fitopatologiya= Mycology and Phytopathology. 2020;54(1):49-58. DOI10.31857/S0026364820010092. (in Russian)Sreenivasulu N., Schnurbusch T. A genetic playground for enhancinggrain number in cereals. Trends Plant Sci. 2012;17(2):91-101.DOI 10.1016/j.tplants.2011.11.003Stasyuk А.I., Leonova I.N., Salina Е.А. Variability of agronomicallyimportant traits in spring wheat hybrids obtained by marker-assistedselection from crosses of winter wheat with spring wheatdonors of resistance genes. Sel’skokhozyaistvennaya Biologiya =Agricultural Biology. 2017;52(3):526-534. DOI 10.15389/agrobiology.2017.3. 526eng.State Standard 9353-2016. Wheat: Specifications. 2018. Availableat: http://docs.cntd.ru/document/1200139414 (in Russian)State Standard 26574-2017. Wheat Bakery Flour: Specifications(amended). 2019. Available at: http://docs.cntd.ru/document/1200157423 (in Russian)Sukumaran S., Lopes M., Dreisigacker S., Reynolds M. Geneticanalysis of multi environmental spring wheat trials identifiesgenomic regions for locus-specific tradeoffs for grain weightand grain number. Theor. Appl. Genet. 2018;131:985-998. DOI10.1007/s00122-017-3037-7.Syukov V.V., Shabolkina E.N., Shevchenko S.N., Vyushkov A.A.Spring soft wheat Tulaykovskaya 110. Molodoy Uchenyy = YoungScientist. 2016;27.3:57-60. (in Russian)Tsitsin N.V. Remote Hybridization of Plants. Moscow: SelkhozgizPubl., 1954;3-64. (in Russian)Ugarte C.C., Trupkin S.A., Ghiglione H., Slafer G., Casal J.J. Lowred/far-red ratios delay spike and stem growth in wheat. J. Exp.Bot. 2010;61(11):3151-3162. DOI 10.1093/jxb/erq140.Upelniek V.P., Belov V.I., Ivanova L.P., Dolgova S.P., Demidov A.S.Heritage of academician N.V. Tsitsin: state-of-the-art and potentialof the collection of intermediate wheat × couch-grass hybrids.Vavilovskii Zhurnal Genetiki i Selektsii = Vavilov Journal of Geneticsand Breeding. 2012;16(3):667-674. (in Russian)Volkova L.V., Bebyakin V.M., Lyskova I.V. Plasticity and stabilityof spring wheat varieties and breeding forms according to grainproductivity and quality. Russ. Agricult. Sci. 2010;36(1):1-4. DOI10.3103/S1068367410010015.Wang M.J., Zhang Y., Lin Z.S., Ye X.G., Yuan Y.P., Ma W., Xin Z.Y.Development of EST-PCR markers for Thinopyrum intermediumchromosome 2Ai#2 and their application in characterization ofnovelwheat-grass recombinants. Theor. Appl. Genet. 2010;121:1369-1380. DOI 10.1007/s00122-010-1394-6.Wang R.R.C. Agropyron and Psathyrostachys. In: Kole C. (Ed.). WildCrop Relatives: Genomic Breeding Resources. Springer, Berlin,Heidelberg, 2011;77-108. DOI 10.1007/978-3-642-14228-4_2Wolde G.M., Mascher M., Schnurbusch T. Genetic modification ofspikelet arrangement in wheat increases grain number without significantly affecting grain weight. Mol. Genet. Genomics. 2019;294:457-468. DOI 10.1007/s00438-018-1523-5.Wu J., Yang X., Wang H., Li H., Li L., Li X., Liu W. The introgressionof chromosome 6P specifying for increased numbers offlorets and kernels from Agropyron cristatum into wheat. Theor.Appl. Genet. 2006;114:13-20. DOI 10.1007/s00122-006-0405-0.Zeleneva Yu.V. Substantiation of the genetic protection of wheatfrom diseases in the Central Chernozem Belt. Dr. Biol. Sci. Diss.St. Petesburg; Pushkin, 2019. Available at: https://rusneb.ru/catalog/000200_000018_RU_NLR_BIBL_A_012131792/ (in Russian)Zeng J., Cao W., Fedak G., Sun S., Mccallum B., Fetch T., Xue A.,Zhou Y. Molecular cytological characterization of two novel durum– Thinopyrum intermedium partial amphiploids with resistanceto leaf rust, stem rust and Fusarium head blight. Hereditas.2013;150(1):10-16. DOI 10.1111/j.1601-5223.2012.02262.x.Zeng Z.-X., Yang Z.-J., Hu L.-J., Liu C., Li G.R., Ren Z.-L. Developmentof St genome specific ISSR marker. Acta Bot. Boreal. Occident.Sin. 2008;28(8):1533-1540.Zhang P., Li W., Fellers J., Friebe B., Gill B.S. BAC-FISH in wheatidentifies chromosome landmarks consisting of different types oftransposable elements. Chromosoma. 2004;112:288-299. DOI10.1007/s00412-004-0273-9.Zhang Z.Y., Xin Z.Y., Larkin P.J. Molecular characterization ofa Thinopyrum intermedium group 2 chromosome (2Ai-2) conferringresistance to barley yellow dwarf virus. Genome. 2001;44(6):1129-1135. DOI 10.1139/g01-083.Zheng Q., Lv Z., Niu Z., Li B., Li H., Xu S.S., Han F., Li Z. Molecularcytogenetic characterization and stem rust resistance offive wheat-Thinopyrum ponticum partial amphiploids. J. Genet.Genomics. 2014;41(11):591-599. DOI 10.1016/j.jgg.2014.06.003.


Wart (a disease caused by Synchytrium endobioticum) and golden cyst potato nematode (Globodera rostochiensis),which parasitize the roots of the host plant, cause signif icant damage to potato crop. Both of these diseasefactors are quarantined in the Russian Federation, and each registered variety is tested for resistance to their mostcommon races and pathotypes. The main method of opposing such diseases is by the development of resistant varieties.An important step in this process is the selection of resistant genotypes from the population and the estimationof the resistance of hybrids obtained by crosses during the breeding process. Conducting a permanent phenotypicevaluation is associated with diff iculties, for example, it is not always possible to work with pathogens, and phenotypicevaluation is very costly and time consuming. However, the use of DNA markers linked to resistance genes cansignif icantly speed up and reduce the cost of the breeding process. The aim of the study was to screen the GenAgropotato collection of ICG SB RAS using known diagnostic PCR markers linked to golden potato cyst nematode and wartresistance. Genotyping was carried out on 73 potato samples using three DNA markers 57R, CP113, Gro1-4 associatedwith nematode resistance and one marker, NL25, associated with wart resistance. The genotyping data were comparedwith the data on the resistance of the collection samples. Only the 57R marker had a high level of correlation  between resistance and the presence of a diagnostic fragment. The diagnosticeff iciency of the 57R marker was 86.11 %. This marker can be successfully used for screening a collection, searchingfor resistant genotypes and marker-assisted selection. The other markers showed a low correlation between the presenceof the DNA marker and resistance. The diagnostic eff iciency of the CP113 marker was only 44.44 %. Spearman’scorrelation coeff icient  did not show signif icant correlation betweenresistance and the DNA marker. The diagnostic eff iciency of the NL25 marker was 61.11 %. No signif icant correlationwas found between the NL25 marker and resistance . The use of thesemarkers for the search for resistant samples is not advisable. Potato is one of the most important crops in the world andis the world’s fifth largest staple food crop by volume . One of the possible reasons fora decrease in yield is the damage of potatoes by various factors.Especially dangerous for potatoes are golden potato cystnematode (Globodera rostochiensis) and potato wart (pathogen– Synchytrium endobioticum). They are quarantined in theRussian Federation. Data on resistance to G. rostochiensis andS. endobioticum are required when registering a potato varietyin the State Register of Selection Achievements Authorizedfor Use .Potato cyst nematode (PCN) can cause significant damageto the potato yield, which can reach 80–90 % . Today, 5 pathotypes of this pestare known in the world: Ro1, Ro2, Ro3, Ro4, Ro5 , while in Russia only the Ro1pathotype of PCN has been detected at the moment .Potato wart affects from 35  to 100 % of the yield. There are 43 wart pathogensin Europe today . Only a few varietiesaffected by this disease are registered in the State Registerof Selection Achievements .One of the main methods of dealing with these pests isthe development of resistant potato varieties. Accordingly,it is important to detect genes responsible for resistance toPCN, study their heritability, develop DNA markers linkedto these genes, and use genes in breeding in marker-assistedselection schemes.The potato has 7 loci of resistance to PCN on chromosomesIII ), V , H1 ,GroV1 ), VII ), X ),XI ). Four loci  provide partial resistance, while three others  give high resistance toone or more pathotypes . DNA markers havemade it possible to identify complex loci containing severalR-genes, including a locus containing two genes for PCN resistance, which was identified on chromosome Vin two different potato species .The H1 resistance gene is introgressed into breeding varietiesfrom Solanum tuberosum ssp. andigenum and S. vernei. This gene is dominant anddetermines resistance to pathotypes Ro1 and Ro4 of G. rostochiensis; according to other data, it determines resistanceto pathotypes Ro5 and Ro6 . This gene is located at the distal part of thelong arm of the V chromosome  and encodes the CC-NBS-LRR protein (coiledcoil/nucleotide-binding/leucine-rich repeat). The H1 gene isthe only nematode resistance gene for which Flora’s geneto-gene interaction concept has been validated by classicalgenetic analysis . The H1 resistance gene corresponded to theAvr gene of golden potato cyst nematode G. rostochiensis.The GroV1 gene originates from the wild potato speciesS. vernei, is linked to the H1 locus ,and is responsible for resistance to the Ro1 pathotype ofG. rostochiensis .The Gro1 locus is localized on chromosome VII andcontains a family of genes Gro1-1, Gro1-2, Gro1-3, Gro1-4,Gro1-5, Gro1-6, Gro1-8, Gro1-10, Gro1-11, Gro1-12 andGro1-14, as well as a number of pseudogenes . J. Paal andcolleagues showed that the Gro1-4 gene is a monogenicdominant gene responsible for resistance to the Ro1 pathotypeof G. rostochiensis and encodes a protein belonging to theTIR-NB-LRR class of proteins. Gro1-4 was introduced into S. tuberosum from the wild potato S. spegazzinii .A number of loci of quantitative traits associated with resistanceto cyst nematodes were mapped in the potato genome:Gro1.2, Gro1.3, and Gro1.4 determining resistance to G. rostochiensiswere localized on chromosomes X, XI, and III. Inthis case, S. spegazzinii was the source of resistance .The Grp1 locus provides a broad spectrum of resistance toboth cyst nematodes G. rostochiensis and G. pallida. It hasbeen mapped to chromosome V  and determines resistance to the Ro5 pathotypeof G. rostochiensis .A significant number of diagnostic DNA markers have beendeveloped for the H1 gene. Among them are markers CD78, TG689 , N146, N195 , CP113 , TG689/TG689indel12 , 239E4left , EM15 (repulsion) and CMI (coupling) , 57R . Markers have also been designed forother genes and QTLs. For example, markers TG69 , SCAR-U14, and SCAR-X02 have been developedfor the GroV1 gene ; markers CP56 and St3.3.2 , CP56, CP51(c), GP516(c) were selectedfor the Gro1 locus . MarkersGro1-4  and Gro1-4-1  were designed forthe Gro1-4 gene. For Grp1-QTL, markers GP21 and GP179, TG432  have been developed.The TG63 marker was selected for Gro1.2-QTL . Markers Ssp75 and TG30 have been developedfor Gro1.3-QTL . The Ssp8 marker wasdesigned for Gro1.4-QTL .A number of genes for resistance to wart (S. endobioticum)have been found in potatoes. These are the followinggenes: Sen1, located on the XI chromosome ; Sen1- 4 mapped to chromosome IV ; locus Sen18-IX, located on chromosome IX; locusSen2/6/18- I, located on chromosome I ;locus Xla-TNL found on chromosome XI ; the Sen2 locus mapped to chromosome XI ; the Sen3 locus was mapped on chromosome XIin the same region as the Sen1 gene ; the authors suggested that Sen3 could be either a Sen1paralogue from the same cluster or an allelic variant of theSen1 gene.QTLs responsible for resistance to races 1, 2, 6 and 18 ofwart are found on other chromosomes: chromosome I (torace 2), chromosome II , chromosome VI , chromosome VII , chromosomeVIII , chromosome X , chromosome XI  .J.E. Obidiegwu and colleagues also found additional wartresistance loci on chromosomes I, IV, X, XI, and XII thatwere less influential than the main genes . Minor QTLs located on the chromosome X furtheraffect resistance to race 18 of wart .The Sen1 and Sen1-4 genes determine the resistance torace 1 of the potato wart pathogen; in both cases, resistanceis determined by the dominant alleles of the genes. The Sen1gene is located at the distal part of the long arm of chromosomeXI . However,it should be noted that J.E. Obidiegwu et al. (2015), usinggenome-wide association studies (GWAS), identified theSen1/ RSe-XIa multi-allelic locus on potato chromosome XIas the main factor of resistance to four S. endobioticum races . The Sen1-4gene is located on the long arm of chromosome IV at a distanceof 5 cM from the centromere .The Xla-TNL locus on potato chromosome XI is linked toresistance to races 18 and 6 and can be considered as one ofthe main factors of wart resistance .The Sen2 locus is mapped to chromosome XI and isa dominant monogenic locus that provides a high level ofresistance to eight races of S. endobioticum simultaneously:1 (D1), 2 (G1), 6 (O1), 8 (F1), 18 (T1), 2 (Ch1), 3 (M1) and39 (P1). The genetic and physical distances between the Sen1and Sen2 loci were indirectly estimated at 63 cM and 32 Mbp,respectively .Sen3 is a dominant monogenic locus of resistance to races 2,6, and 18 . Locus Sen18-IX (chromosomeIX) determines resistance to race 18 S. endobioticum,and locus Sen2/6/18-I (chromosome I) to races 2, 6, and 18.A. Ballvora et al. (2011) note that resistances to races 2, 6and 18 correlate with each other, but are inherited regardlessof resistance to race 1.Several markers have been developed to detect the dominantallele of the Sen1 gene: CP58, GP125 ,NL25 , Sti046, St_At5g16710, GP125 and GP259 . Also, using a genome-wide association studies,a haplotype-specific marker PotVar0067008 associated withSen1 was identified .To identify the Sen18-IX locus, markers GP129, GP101and STM3023b can be used. The Sen2/6/18-I locus can bediagnosed using markers STM2030, SC176, GP192, GP124,and GP194 . Markers Kc8103 and RK36,located on chromosome XI and linked to the Xla-TNL locus,have shown potential diagnostic value in determining resistanceto races 18 and 6 of S. endobioticum . Three markers, 5450_3, 2502_1, and 2502_3, linked tothe Sen2 locus were developed . It is possibleto use the markers chr11_1259552 and chr11_1772869to detect Sen3 .The aim of the study was to screen the GenAgro potato collectionof the Institute of Cytology and Genetics of the SiberianBranch of the Russian Academy of Sciences (ICG SB RAS)using known diagnostic PCR markers linked to resistance togolden cyst potato nematode and potato wart.Plant material. The research material was the collection ofvarieties and hybrids of potatoes named the “GenAgro” plantcollection of the ICG SB RAS. The collection was representedby 73 varieties and hybrids of potatoes (Solanum tuberosum)(Supplement 1)1. The plants were grown in the field on theterritory of the Michurinsky village, Novosibirsk region, fromMay to August 2017.http://vavilov.elpub.ru/jour/manager/f iles/Suppl_Totsky_Engl.pdfSupplementary Materials are available in the online version of the paper:Field tests were carried out according to the followingscheme: the number of rows for each genotype was two; thenumber of plants in a row – 10; row length – 3 m; distancebetween the rows – 0.75 m; distance between the plants inrows – 0.30 m; planting method – manually (by hand) on furrows,filling furrows with harrows; landing date is the thirddecade of May.Agrochemical characteristics of the soil: the content ofexchanged potassium 110.00 mg/kg; the amount of exchangedbases 24.19 mg-eq/100 g; hydrolytic acidity 3.23 mg-eq/100 g;exchanged acidity 5.60 mg-eq/100 g; humus content 2.67 %;the content of mobile phosphorus 5.14 mg/kg; the degree ofsaturation with bases (V) 88.20 %.Most of the data on resistance to PCN and potato wart weretaken from references, namely from the database of the StateRegister of Selection Achievements Authorized for Use , and from the EuropeanCultivated Potato Database (https://www.europotato.org/).Some of the samples and hybrids for which there were nopublished data on resistance were evaluated under experimentalconditions. Determination of resistance to PCN wascarried out in accordance with the methodology recommendedby OEPP/EPPO (2006) at the All-Russian Institute of PlantProtection. Potato wart resistance was evaluated accordingto the Glynn–Lemmerzahl method as described in the EPPODiagnostic protocol for S. endobioticum at the Russian Potato Research Center.DNA isolation and PCR analysis. DNA was isolated fromthe skin of potato tubers using the DNeasy Plant Mini kit  according to the protocol. The concentrationand purity of the tested samples were determined using gelelectrophoresis and a Nanodrop 2000 apparatus.Several diagnostic markers most often used in breedingprograms were selected for genotyping (Table 1). These markerswere associated with R-genes that determine resistanceto race 1 of potato wart (S. endobioticum) and Ro1 pathotypeof potato cyst nematode (G. rostochiensis).Two markers, 57R and CP113, associated with the H1 resistancegene, and the Gro1-4 marker, associated with theGro1-4 resistance gene, were selected to identify PCN resistancegenes (see Table 1). The SCAR PCR marker CP113-5’2/CP113-3’2 was proposed by J. Niewöhner et al. (1995) basedon the RFLP marker CP113. Amplification of DNA of resistantgenotypes using this marker formed product with a 760 bplength. The 57R marker was proposed by L. Schultz et al.(2012). Amplification of DNA of resistant genotypes formedproduct with a 450 bp length. SCAR PCR marker Gro1-4 wasdeveloped by J. Paal et al. (2004) based on the RFLP markerGro1. Amplification of DNA of resistant genotypes formedproduct with a 602 bp length.The NL25 marker was proposed by R. Hehl et al. (1999)when mapping the Sen1 gene. C.A. Bormann et al. (2004)and C. Gebhardt et al. (2006) used this marker for markerassistedselection (see Table 1). Amplification produces oneor two fragments of 1200 or 1400 bp lenght. The presenceof the dominant Sen1 allele is determined by the presence ofa 1400 bp fragment.PCR was carried out in a 20 μL reaction mixture containing100 ng of DNA, 67 mM Tris-HCl (pH 8.8), 1.8 mM MgCl2,0.01 % Tween 20, 0.2 mM each dNTP, 0.25 μM forward andreverse specific primers, 1 unit Taq DNA polymerase.Two types of amplification programs (SSR55 and SSR60)represented the time-temperature profile of PCR. SSR55:(1) first cycle: 94 °C – 2 min; (2) the next 45 cycles: 94 °С –1 minute, 55 °С – 1 minute and 72 °С – 2 minutes; (3) onecycle of 5 minutes at 72 °C (Gro1-4). SSR60: (1) first cycle:94 °C – 2 min; (2) the next 45 cycles: 94 °С – 1 minute, 60 °С –1 minute and 72 °С – 2 minutes; (3) one cycle of 5 minutesat 72 °C .The analysis of the obtained PCR products was carriedout by electrophoresis in a 2 % agarose gel. The results weredocumented using a Molecular Imager Gel Doc XR System(BioRad) using UV light.Statistical processing of the data was carried out usingSpearman’s correlation coefficient; for calculations, theSTATISTICA program was used. The diagnostic efficiency,sensitivity, specificity and predictive value were calculatedusing the MedCalc softwarehttps://www.medcalc.org/Diagnostic efficiency was defined as the proportion of correcttest results in the total number of test results, or the sum oftrue positive and true negative test results divided by the totalnumber of test results. The sensitivity was calculated as thenumber of resistant samples identified using a DNA markerdivided by the total number of resistant samples. Specificityis the number of susceptible samples identified by the DNAmarker divided by the total number of susceptible samples.Positive predictive value was defined as the proportion ofcorrect positive diagnostic test results.Among 73 samples selected for genotyping, 35 were resistantto PCN, 37 samples were susceptible, and in one sample,resistance to nematodes was unknown (Table 2). 69 sampleswere resistant to wart, 3 samples were susceptible to disease,the resistance of one sample was unknown (see Table 2).Genotyping of varieties and hybridsusing markers designed for resistance to PCNThe 57R marker is found in 85.7 % of resistant samples, aswell as in 13.5 % of susceptible ones . Some mismatches can be observeddue to the absence of linkage of the 57R marker with the H1resistance gene in a number of samples. The second reason forthe mismatches can be explained by the presence of other resistancegenes in samples that do not carry the 57R marker. Thediagnostic efficiency of the 57R marker, which is expressedas the percentage of true (both positive and negative) testresults to the total number of results obtained, was 86.11 %.The diagnostic sensitivity of the used marker, which shows thenumber of resistant samples identified using the DNA marker divided by the total number of resistant samples, was 85.71 %.The diagnostic specificity, which is the number of susceptiblesamples identified by the DNA marker divided by the totalnumber of susceptible samples, was 86.48 %. The predictivevalue of a positive result, showing the proportion of correctpositive diagnostic test results, was 85.71 %. Calculation ofthe Spearman correlation coefficient  showed a significant correlation betweenresistance and the 57R marker.The CP113 marker is found in only 48.6 % of resistant accessions,while the marker is present in 62.9 % of susceptiblegenotypes .These results can be regarded as the absence of linkage of themarker with the H1 resistance gene in many samples of the potatocollection. The diagnostic efficiency of the CP113 markerwas only 44.44 %. Diagnostic sensitivity was 48.57 %. Diagnosticspecificity accounted for 40.54 %. The predictive valueof a positive result, indicating the probability of resistancepresence if the test shows a positive result when CP113 markerwas used, was equal to 43.58 %. Spearman’s correlation coefficient inthis case showed no significant correlation between resistanceand DNA marker. The use of such a marker when screeninga population to search for resistant samples is not advisable.29 samples were analyzed using the Gro1-4 marker. Thediagnostic fragment was amplified in only 5 samples. Correspondenceof the presence of the marker in the resistantsample was observed only in 1 case out of 5. In other cases,the marker was found in the samples susceptible to the disease.The data obtained show that when screening populationsfor resistance to PCN, it is advisable to use the 57R marker.Genotyping of varieties and hybridsusing markers linked to resistance to potato wart The NL25 marker is found in 62.3 % of resistant samples,however, the marker is present in two of the three susceptiblegenotypes . This can be explainedby the processes of crossing over and by the fact that in a numberof samples the linkage of the marker and the resistancegene is not observed; however, the small number of sensitivesamples does not allow sufficiently assessing the applicabilityof the marker for breeding. The marker is absent in 27 samplesand only in one case we observe the absence of a marker in thesusceptible sample, in the other cases the marker is absent inthe resistant samples. This can be explained by the presence ofanother resistance gene that is not linked to the NL25 marker.The diagnostic efficiency of resistance using the NL25 markerwas 61.11 %. The diagnostic sensitivity turned out to beat 62.31 %. The diagnostic specificity was only 33.33 %.However, the predictive value of a positive result, showingthe proportion of correct positive diagnostic test results, whenusing the NL25 marker was equal to 95.55 %. It should benoted that such results are associated with the fact that the setof samples contained only three sensitive samples, and twoof them showed the presence of the NL25 marker. Spearman’scorrelation coefficient  in such situation showed the absenceof significant correlations.Despite the fact that the NL25 marker is often used inscreening and marker selection, a study in our set of samplesshowed that its use does not guarantee a reliable result.In our study, 13 resistant to golden potato nematode samplesthat had both markers (57R and CP113) linked to the H1nematode resistance gene were found. In addition, there are8 genotypes resistant to nematodes and wart and carryingboth the 57R and CP113 markers linked to the H1 nematoderesistance gene and the NL25 marker linked to the Sen1 wartresistance gene. There is also one sample (Safo) in the populationthat is resistant to wart and nematodes and carries all threemarkers 57R, CP113, Gro1-4, linked to nematode resistance,and marker NL25, linked to wart resistance.The NL25 marker linked to the Sen1 gene, which providesresistance to pathotype 1 of potato wart, is successfully usedin the practice of marker-oriented selection. So, C. Gebhardtand colleagues reported that after screening 17 plants in twofamilies of segregating populations using the NL25 marker, 14 genotypes with the marker were identified. All these plantswere found to be resistant to pathotype 1 S. endobioticum.Some were also resistant to pathotype 2 and/or pathotype 6.The effectiveness of this marker is also reported by O.Y. Antonovaand colleagues who analyzed 98 varieties using theNL25 marker. A diagnostic component was found in 95 studiedwart-resistant varieties, while it was not found in threesusceptible varieties. This shows a high level of correlationbetween the presence or absence of the marker and the resistanceand sensitivity of the genotype to wart, respectively.However, A. Khiutti and colleagues, when screening 52 genotypesusing the NL25 marker, found that 39 samples (bothsensitive and resistant genotypes) had the same nondiagnosticfragment, 12 genotypes did not have amplification of theNL25 marker fragments. Only 5 out of 52 genotypes hada diagnostic fragment indicating the presence of a resistancegene. Four of these five accessions were resistant, but onegenotype was found to be sensitive; most resistant genotypesdid not have a 1400 bp diagnostic fragment predicting a resistantphenotype .Our analysis also did not allow us to speak about the reliabilityof using the NL25 marker for screening resistantvarieties.Using the Gro1-4 marker in a segregating population, C. Gebhardtand colleagues found that all 45 plants carrying thismarker linked to the Gro1 gene were resistant to the Ro1 pathotypeof G. rostochiensis .C. Gebhardt and colleagues in 1993 found in a segregatingpopulation that the CP113 marker is linked to the H1 geneso strongly that it has zero recombination . However, D. Milczarek and colleagues (2011) reportedthat the CP113 marker was amplified for all tested varieties,resistant and sensitive, and was unsuitable for the selectionof resistant clones. A similar picture is observed in our work.The 57R SCAR marker was tested in a mapping population,where it was linked to the H1 locus and nematoderesistance . Later L. Schultzand colleagues reported that they analyzed two independentpopulations of 281 and 122 potato samples with knownresistance/sensitivity using the 57R SCAR marker. Whenscreening the first population, the 57R marker revealed a correspondencebetween genotype and phenotype, 89 out of90 resistant varieties had an allele associated with resistance.Only one resistant variety, in which no marker amplificationwas observed, became an exception. None of the 191 PCNsusceptible varieties had an allele predicting resistance. Thenanother independent population of 122 varieties was screened.All varieties showed complete correspondence between resistanceto G. rostochiensis and the presence/absence of the57R allele, corresponding to the presence of the resistancegene .O.Y. Antonova et al. (2016) identified the 57R markerin 33 (30.3 %) of 109 breeding varieties they studied. Theoverwhelming majority of the varieties with the diagnosed57R fragment were resistant or weakly affected by the nematode.The correspondence between resistance and the presenceof a diagnostic fragment was high – 93.5 %. At the same time,only four genotypes with the Gro1-4 marker were identified:two resistant varieties, one weakly affected variety and onesusceptible. All these four varieties, along with the Gro1-4marker, also possessed the H1 gene markers – 57R, TG689,N146, N195 .In the work of N.S. Klimenko et al. (2017) showed the presenceof the 57R marker in 24 out of 103 samples, while themarker was found in 15 resistant and 2 susceptible samples.It was shown that the correlation between the presence of atleast one marker of the H1 gene and the data on the nematoderesistance of varieties was +0.92 .T.A. Gavrilenko et al. (2018) showed that out of 39 samplesof the studied set of samples, 15 had a dominant allele ofthe H1 gene (based on a number of DNA markers), and twovarieties had dominant alleles of both H1 and Gro1-4 genes.At the same time, none of the markers was identified in theremaining 22 genotypes. Comparison of these results withresistance to G. rostochiensis (pathotype Ro1) showed thatall accessions with H1 gene markers are nematode resistant,while varieties affected by G. rostochiensis did not have thesemarkers . This high correlation shows the reliability of the markers used in the study, which can beused to select resistant samples.It should be noted that the saturation of the genotype withgenes of resistance to the nematode does not affect its economicallyvaluable traits. At the same time, there is a stronglink between the presence of the marker and resistance. So, inthe study of D. Milczarek and colleagues in 2014, the relationshipbetween the presence of markers TG689 and 57R linkedto the H1 gene, which determines resistance to the nematodeG. rostochiensis, and valuable agricultural traits is presented.Clones with these markers had a higher total yield of tubersand total starch yield than clones without markers. There wasno negative association between marker presence and quality.All 347 seedlings obtained after three crosses were genotypedusing both markers and phenotypically evaluated for resistanceto the Ro1 pathotype of G. rostochiensis. Of these, 316 (i. e.91 %) and 325 (94 %) clones were resistant and carried theTG689 or 57R markers .In general, our data on the 57R marker are quite close to theresults described above and confirm the high reliability ofthe work of this marker, which suggests the need to use thismarker when selecting samples resistant to PCN.The authors declare no conflict of interest.Antonova O.Y., Shvachko N.A., Novikova L.Y., Shuvalov O.Y., KostinaL.I., Klimenko N.S., Shuvalova A.R., Gavrilenko T.A. Geneticdiversity of potato varieties bred in Russia and its neighboring countriesbased on the polymorphism of SSR-loci and markers associatedwith resistance R-genes. Russ. J. Genet. Appl. Res. 2017;7(5):489-500. DOI 10.1134/S2079059717050021.Asano K., Kobayashi A., Tsuda S., Nishinaka M., Tamiya S. DNAmarker-assisted evaluation of potato genotypes for potential resistanceto potato cyst nematode pathotypes not yet invading into Japan.Breed. Sci. 2012;62(2):142-150. DOI 10.1270/jsbbs.62.142.Baayen R.P., Cochius G., Hendriks H., Meffert J.P., Bakker J., BekkerM., van den Boogert P.H.J.F., Stachewicz H., van LeeuwenG.C.M. History of potato wart disease in Europe – a proposalfor harmonisation in defining pathotypes. Eur. J. Plant Pathol.2006;116(1):21-31. DOI 10.1007/s10658-006-9039-y.Bakker E., Achenbach U., Bakker J., van Vliet J., Peleman J., Segers B.,van der Heijden S., van der Linde P., Graveland R., Hutten R., vanEck H., Coppoolse E., van der Vossen E., Bakker J., Goverse A.A high-resolution map of the H1 locus harbouring resistance to thepotato cyst nematode Globodera rostochiensis. Theor. Appl. Genet.2004;109(1):146-152. DOI 10.1007/s00122-004-1606-z. Epub 2004Feb 25.Ballvora A., Flath K., Lubeck J., Strahwald J., Tacke E., HofferbertH.- R., Gebhardt C. Multiple alleles for resistance and susceptibilitymodulate the defense response in the interaction of tetraploidpotato (Solanum tuberosum) with Synchytrium endobioticum pathotypes1, 2, 6 and 18. Theor. Appl. Genet. 2011;123(8):1281-1292.DOI 10.1007/s00122-011-1666-9. Epub 2011 Aug 6.Ballvora A., Hesselbach J., Niewöhner J., Leister D., Salamini F., GebhardtC. Marker enrichment and high-resolution map of the segmentof potato chromosome VII harbouring the nematode resistancegene Gro1. Mol. General Genet. 1995;249:82-90. DOI 10.1007/BF00290239.Barone A., Ritter E., Schachtschabel U., Debener T., Salamini F., GebhardtC. Localization by restriction fragment length polymorphismmapping in potato of a major dominant gene conferring resistanceto the potato cyst nematode Globodera rostochiensis. Mol. GeneralGenet. 1990;224(2):177-182. DOI 10.1007/BF00271550.Bartkiewicz A., Chilla F., Terefe-Ayana D., Lübeck J., Strahwald J.,Tacke E., Hoferbert H.-R., Flath K., Linde M., Debener T. Improvedgenetic resolution for linkage mapping of resistance to potato wartin monoparental dihaploids with potential diagnostic value in tetraploidpotato varieties. Theor. Appl. Genet. 2018;131:2555-2566.DOI 10.1007/s00122-018-3172-9.Bormann C.A., Rickert A.M., Ruiz R.A.C., Paal J., Lübeck J., StrahwaldJ., Buhr K., Gebhardt C. Tagging quantitative trait loci formaturity-corrected late blight resistance in tetraploid potato withPCR-based candidate gene markers. Mol. Plant-Microbe Interact.2004;17(10):1126-1138. DOI 10.1094/MPMI.2004.17.10.1126.Brugmans B., Hutten R.G.B., Rookmaker N., Visser R.G.F., vanEck H.J. Exploitation of a marker dense linkage map of potato forpositional cloning of a wart disease resistance gene. Theor. Appl.Genet. 2006;112(2):269-277. DOI 10.1007/s00122-005-0125-x.Finkers-Tomczak A., Bakker E., Boer J., Vossen E., Achenbach U.,Golas T., Suryaningrat S., Smant G., Bakker J., Goverse A. Comparativesequence analysis of the potato cyst nematode resistance locusH1 reveals a major lack of co-linearity between three haplotypesin potato (Solanum tuberosum ssp.). Theor. Appl. Genet. 2011;122:595-608. DOI 10.1007/s00122-010-1472-9.Finkers-Tomczak A., Danan S., van Dijk T., Beyene A., Bouwman L.,Overmars H., van Eck H., Goverse A., Bakker J., Bakker E. A highresolutionmap of the Grp1 locus on chromosome V of potato harbouringbroad-spectrum resistance to the cyst nematode speciesGlobodera pallida and Globodera rostochiensis. Theor. Appl. Genet.2009;119(1):165-173. DOI 10.1007/s00122-009-1026-1.Flor H.H. Current status of the gene-for-gene concept. Annu. Rev.Phytopathol. 1971;9:275-296. DOI 10.1146/annurev.py.09.090171.001423.Food and Agriculture Organization of the United Nations. World Foodand Agriculture – Statistical pocketbook 2019. Rome: FAO, 2019.Available at: http://www.fao.org/3/ca6463en/ca6463en.pdf.Galek R., Rurek M., De Jong W.S., Pietkiewicz G., Augustyniak H.,Sawicka-Sienkiewicz E. Application of DNA markers linked to thepotato H1 gene conferring resistance to pathotype Ro1 of Globoderarostochiensis. J. Appl. Genet. 2011;52(4):407-411. DOI 10.1007/s13353-011-0056-y.Gavrilenko Т.А., Klimenko N.S., Antonova O.Yu., Lebedeva V.A.,EvdokimovaZ.Z., Gadjiyev N.M., Apalikova O.V., Alpatyeva N.V.,Kostina L.I., Zoteyeva N.M., Mamadbokirova F.T., Egorova K.V.Molecular screening of potato varieties bred in the northwesternzone of the Russian Federаtion. Vavilovskii Zhurnal Genetiki i Selektsii= Vavilov Journal of Genetics and Breeding. 2018;22(1):35-45.DOI 10.18699/VJ18.329. (in Russian)Gebhardt C., Ballvora A., Walkemeier B., Oberhagemann P., Schüler K.Assessing genetic potential in germplasm collections of crop plantsby marker-trait association: a case study for potatoes with quantitativevariation of resistance to late blight and maturity type. Mol. Breed.2004;13:93-102. DOI 10.1023/B:MOLB.0000012878.89855.df.Gebhardt C., Bellin D., Henselewski H., Lehmann W., SchwarzfischerJ., Valkonen J. Marker-assisted combination of major genesfor pathogen resistance in potato. Theor. Appl. Genet. 2006;112(8):1458-1464. DOI 10.1007/s00122-006-0248-8. Epub 2006Mar 15.Gebhardt C., Mugniery D., Ritter E., Salamini F., Bonnel E. Identificationof RFLP markers closely linked to the H1 gene conferringresistance to Globodera rostochiensis in potato. Theor. Appl. Genet.1993;85:541-544. DOI 10.1007/BF00220911.Gebhardt C., Valkonen J.P.T. Organization of genes controlling diseaseresistance in the potato genome. Annu. Rev. Phytopathol. 2001;39:79-102. DOI 10.1146/annurev.phyto.39.1.79.Groth J., Song Y., Kellermann A., Schwarzfischer A. Molecular characterisationof resistance against potato wart races 1, 2, 6 and 18 ina tetraploid population of potato (Solanum tuberosum subsp. tuberosum).J. Appl. Genet. 2013;54(2):169-178. DOI 10.1007/s13353-013-0141-5. Epub 2013 Feb 24.Hampson М.С. History, biology and control of potato wart disease inCanada. Can. J. Plant Pathol. 1993;15(4):223-244. DOI 10.1080/07060669309501918.Hehl R., Faurie E., Hesselbach J., Salamini F., Whitham S., Baker B.,Gebhardt C. TMV resistance gene N homologues are linked to Synchytriumendobioticum resistance in potato. Theor. Appl. Genet.1999;98:379-386. DOI 10.1007/s001220051083.Jacobs J.M.E., Eck H.J., Horsman K., Arens P.F.P., Verkerk-Bakker B.,Jacobsen E., Pereira A., Stiekema W.J. Mapping of resistance to thepotato cyst nematode Globodera rostochiensis from the wild potatospecies Solanum vernei. Mol. Breed. 1996;2:51-60. DOI 10.1007/BF00171351.Janssen R., Bakker J., Gommers F.J. Mendelian proof for a gene-forgenerelationship between virulence of Globodera rostochiensisand the H1 resistance gene in Solanum tuberosum ssp. andigenaCPC 1673. Rev. de Nematol. 1991;14(2):207-211.Jones F.G.W., Parrott D.M., Perry J.N. The gene-for-gene relationshipand its significance for potato cyst nematodes and their solanaceoushosts. In: Zuckerman B.M., Rohde R.A. (Eds.). Plant Parasitic Nematodes.Vol. 3. New York: Acad. Press, 1981;23-36.Khiutti A., Afanasenko O., Antonova O., Shuvalov O., Novikova L.,Krylova E., Chalaya N., Mironenko N., Spooner D., Gavrilenko T.Characterization of resistance to Synchytrium endobioticum in cultivatedpotato accessions from the collection of Vavilov Institute ofPlant Industry. Plant Breed. 2012;131(6):744-750. DOI 10.1111/j.1439-0523.2012.02005.x.Khiutti А.V., Antonova O.Yu., Mironenko N.V., Gavrilenko T.A.,Afanasenko O.S. Potato resistance to quarantine diseases. Russ. J.Genet. Appl. Res. 2017;7(8):833-844. DOI 10.1134/S2079059717050094.Klimenko N.S., Antonova O.Yu., Kostina L.I., Mamadbokirova F.T.,Gavrilenko T.A. Marker-assisted selection of Russian potato varietieswith markers of genes for resistance to potato golden nematode(pathotype Ro1). Trudy po Prikladnoy Botanike, Genetike i Selektsii= Proceedings on Applied Botany, Genetics, and Breeding.2017;178(4):66-75. DOI 10.30901/2227-8834-2017-4-66-75. (inRussian)Koretsky P.M. Harmfulness of potato wart in household plots in areasof widespread of the disease in Ukraine. Mikologiya i Fitopatologiya= Mycology and Phytopathology. 1970;4(4):366-369. (in Russian)Kort J., Stone A.R., Rumpenhorst H.J., Ross H. An international schemefor identifying and classifying pathotypes of potato cyst-nematodesGlobodera rostochiensis and G. pallida. Nematologica. 1977;23(3):333-339. DOI 10.1163/187529277x00057.Kreike C.M., De Koning J.R.A., Vinke J.H., Van Ooijen J.W., StiekemaW.J. Mapping of loci involved in quantitatively inherited resistanceto the potato cyst-nematode Globodera rostochiensis pathotypeRo1. Theor. Appl. Genet. 1993;87:464-470. DOI 10.1007/BF00215092.Kreike C.M., Kok-Westeneng A.A., Vinke J.H., Stiekema W.J. Mappingof QTLs involved in nematode resistance, tuber yield and rootdevelopment. Theor. Appl. Genet. 1996;92:463-470. DOI 10.1007/BF00223694.Kuhl J.C. Mapping and tagging of simply inherited traits. In: BradeenJ.M., Chittaranjan K. (Eds.). Genetics, Genomics and Breedingof Potato. Enfield, New Hampshire: Sci. Publishers, 2011;90-112.Leister D., Ballvora A., Salamini F., Gebhardt C. A PCR based approachfor isolating pathogen resistance genes from potato with potentialfor wide application in plants. Nat. Genet. 1996;14:421-429.DOI 10.1038/ng1296-421.Limantseva L., Mironenko N., Shuvalov O., Antonova O., Khiutti A.,Novikova L., Afanasenko O., Spooner D., Gavrilenko T. Characterizationof resistance to Globodera rostochiensis pathotype Ro1in cultivated and wild potato species accessions from the VavilovInstitute of Plant Industry. Plant Breed. 2014;133(5):660-665. DOI10.1111/pbr.12195.Lopez-Pardo R., Barandalla L., Ritter E., de Galarreta J.I.R. Validationof molecular markers for pathogen resistance in potato. Plant Breed.2013;132:246-251. DOI 10.1111/pbr.12062.Milczarek D., Flis B., Przetakiewicz A. Suitability of molecular markersfor selection of potatoes resistant to Globodera spp. Am. J.Potato Res. 2011;88:245-255. DOI 10.1007/s12230-011-9189-0.Milczarek D., Przetakiewicz A., Kaminski P., Flis B. Early selection ofpotato clones with the H1 resistance gene – the relation of nematoderesistance to quality characteristics. Czech J. Genet. Plant Breed.2014;50(4):278-284. DOI 10.17221/114/2014-CJGPB.Mori K., Sakamoto Y., Mukojima N., Tamiya S., Nakao T., Ishii T., HosakaK. Development of a multiplex PCR method for simultaneousdetection of diagnostic DNA markers of five disease and pest resistancegenes in potato. Euphytica. 2011;180:347-355. DOI 10.1007/s10681-011-0381-6.Niewöhner J., Salamini F., Gebhardt C. Development of PCR assaysdiagnostic for RFLP marker alleles closely linked to alleles Gro1and H1, conferring resistance to the root cyst nematode Globoderarostochiensis in potato. Mol. Breed. 1995;1:65-78. DOI 10.1007/BF01682090.Obidiegwu J.E., Flath K., Gebhardt C. Managing potato wart: a reviewof present research status and future perspective. Theor. Appl. Genet.2014;127(4):763-780. DOI 10.1007/s00122-014-2268-0.Obidiegwu J.E., Sanetomo R., Flath K., Tacke E., Hoferbert H.-R.,Hofmann A., Walkemeier B., Gebhardt C. Genomic architecture ofpotato resistance to Synchytrium endobioticum disentangled usingSSR markers and the 8.3 k SolCAP SNP genotyping array. BMCGenet. 2015;16:38. DOI 10.1186/s12863-015-0195-y.OEPP/EPPO Standards PM 7/28. Diagnostic protocols for regulatedpests: Synchytrium endobioticum. Bulletin OEPP/EPPO Bulletin.2004;34:213-218. DOI 10.1111/j.1365-2338.2004.00722.x.OEPP/EPPO Testing of potato varieties to assess resistance to Globoderarostochiensis and Globodera pallida. Bulletin OEPP/EPPO Bulletin. 2006;36:419-420. DOI 10.1111/j.1365-2338.2006.01032.x.Paal J., Henselewski H., Muth J., Meksem K., Menéndez C.M., SalaminiF., Ballvora A., Gebhardt C. Molecular cloning of the potatoGro1-4 gene conferring resistance to pathotype Ro1 of theroot cyst nematode Globodera rostochiensis, based on a candidategene approach. Plant J. 2004;38(2):285-297. DOI 10.1111/j.1365-313X.2004.02047.x.Pajerowska-Mukhtar K., Stich B., Achenbach U., Ballvora A., LübeckJ., Strahwald J., Tacke E., Hofferbert H.-R., Ilarionova E., BellinD., Walkemeier B., Basekow R., Kersten B., Gebhardt C. Singlenucleotide polymorphisms in the allene oxide synthase 2 geneare associated with field resistance to late blight in populations oftetraploid potato cultivars. Genetics. 2009;181(3):1115-1127. DOI10.1534/genetics.108.094268.Pineda O., Bonierbale M.W., Plaisted R.L., Brodie B.B., Tanksley S.D.Identification of RFLP markers linked to the H1 gene conferringresistance to the potato cyst nematode Globodera rostochiensis.Genome. 1993;36(1):152-156. DOI 10.1139/g93-019.Plich J., Przetakiewicz J., Śliwka J., Flis B., Wasilewicz-Flis I., Zimnoch-Guzowska E. Novel gene Sen2 conferring broad-spectrumresistance to Synchytrium endobioticum mapped to potato chromosomeXI. Theor. Appl. Genet. 2018;131:2321-2331. DOI 10.1007/s00122-018-3154-y.Prodhomme C., Esselink D., Borm T., Visser R.G.F., van Eck H.J.,Vossen J.H. Comparative Subsequence Sets Analysis (CoSSA) isa robust approach to identify haplotype specific SNPs; mappingand pedigree analysis of a potato wart disease resistance gene Sen3.Plant Methods. 2019;15:60. DOI 10.1186/s13007-019-0445-5.Prodhomme C., Peter G.V., Paulo M.J., Visser R.G.F., Vossen J.H.,van Eck J.H. Distribution of P1(D1) wart disease resistance in potatogermplasm and GWAS identification of haplotype-specific SNPmarkers. Theor. Appl. Genet. 2020;133:1859-1871. DOI 10.1007/s00122-020-03559-3.Ramakrishnan A.P., Ritland C.E., Blas Sevillano R.H., Riseman A. Reviewof potato molecular markers to enhance trait selection. Am. J.Potato Res. 2015;92(4):455-472. DOI 10.1007/s12230-015-9455-7.Rouppe van der Voort J., Lindeman W., Folkertsma R., Hutten R., OvermarsH., van der Vossen E., Jacobsen E., Bakker J. A QTL for broadspectrumresistance to cyst nematode species (Globodera spp.) mapsto a resistance gene cluster in potato. Theor. Appl. Genet. 1998;96:654-661. DOI 10.1007/s001220050785.Rouppe van der Voort J., van der Vossen E., Bakker E., Overmars H.,van Zandvoort P., Hutten R., Klein Lankhorst R., Bakker J. Two additiveQTLs conferring broadspectrum resistance in potato to Globoderapallida are localized on resistance gene clusters. Theor. Appl.Genet. 2000;101:1122-1130. DOI 10.1007/s001220051588.Schultz L., Cogan N.О.I., McLean K., Dale M.F.B., Bryan G.J., ForsterJ.W., Slater A.T. Evaluation and implementation of a potentialdiagnostic molecular marker for H1-conferred potato cyst nematoderesistance in potato (Solanum tuberosum L.). Plant Breed. 2012;131:315-321. DOI 10.1111/j.1439-0523.2012.01949.x.Skupinová S., Vejl P., Sedlák P., Domkářová J. Segregation of DNAmarkers of potato (Solanum tuberosum ssp. tuberosum L.) resistanceagainst Ro1 pathotype Globodera rostochiensis in selected F1progeny. Rostlinná Výroba. 2002;48(11):480-485. DOI 10.17221/4399-PSE.State Register of Selection Achievements Authorized for Use for ProductionPurposes. Vol. 1. Plant Varieties . Moscow:Rosinformagrotech Publ., 2019. (in Russian)Toxopeus H.J., Huijsman C.A. Breeding for resistance to potato rooteelworm. I. Preliminary data concerning the inheritance and thenature of resistance. Euphytica. 1953;2(3):180-186. DOI 10.1007/BF00053725.


Over 600,000 COVID-19 cases, including >7000 deaths reported to MN Dept of Health (MDH) by June 1, 2021. Clinical trials demonstrated high effectiveness of COVID vaccines. We assessed COVID-19 cases among fully vaccinated residents [vaccine breakthrough (VB) cases]. COVID-19 VB cases were MN residents with completed COVID-19 vaccination series ≥14 days prior to symptom onset or positive for SARS-CoV-2 by nucleic acid amplification or antigen test. COVID-19 cases were reported to MDH and COVID-19 vaccinations reported to the MN Immunization Information Connection (MIIC). COVID-19 cases were matched to MIIC to identify VB and interviewed; medical records of hospitalized cases were reviewed. Available VB case specimens underwent whole genome sequencing (WGS) at MDH or collaborating lab.Jan 19 – June 1, 2021, 2765 VB cases were reported among >2.45 million fully vaccinated residents and 147,445 COVID-19 cases. VB case median (MED) age was 52 y , 83% white, 65% female; MED age of fully vaccinated was 55 y , 77% white, 54% female. Of VB cases, 273 (10%) were hospitalized and 32 (1%) died . 2212 (80%) VB cases were interviewed; 60% reported symptoms; most common were fatigue (53%), rhinorrhea (49%), cough (42%), headache (41%). 35% reported a comorbidity.Of hospitalized VB cases, 120 had completed record reviews. 64 were admitted for COVID-19 related illness  including 27 admitted to ICU . 90% (108) reported a comorbidity, most common being chronic metabolic conditions (46%), obesity (45%), renal disease (31%) and chronic lung disease (26%); 27 were immunocompromised , including immunosuppressive therapy (15), hematological malignancy (9), other cancer (11), and organ transplant recipients (8).Of 604 VB case specimens, 79% were B.1.1.7, 9% B.1.427/429, 3% P.1, and 2% B.1.351; lineage distribution was similar to overall 24,157 MN SARS-CoV2 WGS data.Identified VB cases were 0.1% of those vaccinated and < 2% of total cases reported in the time period. COVID-19 vaccines are an important tool in preventing COVID-19. Additional surveillance, including WGS and case characteristics will be useful to monitor VB.Ruth Lynfield, MD, Nothing to disclose


Salmonella enterica serovar Typhi ISP2825, isolated in 1983 from a Chilean patient, is one of the major S. Typhi strains used for research, along with strains Ty2, CT18, and H58. The complete genome sequence of ISP2825, consisting of a 4,774,014-bp circular chromosome, will help us understand typhoid pathogenesis and evolution. Salmonella enterica serovar Typhi is the causative agent of the life-threatening systemic disease typhoid fever, which is a major cause of infection-mediated morbidity and mortality in countries of endemicity. Humans are the only known host of S. Typhi. Despite its narrow host specificity, S. Typhi has remained a highly successful pathogen since its emergence  and extensively drug-resistant (XDR) strains have become the dominant S. Typhi variants  overnight at 37°C, and its genomic DNA was extracted using the DNeasy blood and tissue kit , without processing additional fragmentation and size selection. The genomic DNA quality and quantity were monitored using a NanoDrop 2000 spectrophotometer  and a Qubit 4 fluorometer (Thermo Fisher Scientific). A genomic DNA library was prepared using a SQK-LSK110 ligation sequencing kit , followed by sequencing with two MinION Flongle flow cells (R9.4.1) using MinKNOW v21.06.0 (ONT). The combined raw reads from two Flongle flow cells were used for base calling using Guppy v5.0.11 (ONT). Fastq files having Q scores of ≥8 were collected, filtered using NanoLyse v1.2.0 (https://github.com/lh3/bwa) and polished sequentially using Racon v1.4.22 (-m 8 -x -6 -g -8 -w 500) (https://github.com/nanoporetech/medaka) (-m r941_min_hac_g507), and Homopolish v0.2.3 (-s bacteria.msh -m R9.4.pkl) (https://github.com/b-brankovics/fasta_tools) was used to set the start position of the polished assembly according to that of S. Typhi CT18 (GenBank accession number GCF_000195995.1) and Ty2 (GCF_000007545.1). The complete genome sequence was annotated using the NCBI Prokaryotic Genome Annotation Pipeline (PGAP)  , Medaka 9.4.pkl) . Fasta_se (PGAP) , and itse (PGAP)  and AMRFe (PGAP) , respecte (PGAP) . Defaulte (PGAP) . OverallS. Typhi ISP2825 has been deposited at GenBank under accession number GCF_019645915.1 or CP080960.1, BioProject accession number PRJNA753482, BioSample accession number SAMN20695325, and Sequence Read Archive (SRA) accession number SRR15411315.The complete genome sequence of


Escherichia coli sequence type 1193 (ST1193) is an important cause of multidrug-resistant extraintestinal infections. Here, we report the complete genome sequence of strain AVS0096, isolated from river water in Switzerland in 2020. The genome consists of a chromosome (4.9 Mbp), a multidrug resistance plasmid (101 kb), and two small plasmids. Escherichia coli lineages sequence type 131-H30 (ST131-H30) and ST1193 are major causative agents of fluoroquinolone-resistant E. coli infections in humans  (–blaCTX-M-27-carrying ST1193 isolate (AVS0096) obtained from river water in Switzerland.The pandemic  (ESBLs) –6. Where(ESBLs) –, 6, few Enterobacteriaceae enrichment (EE) broth (BD) at 37°C for 24 h. One loopful of the enrichment broth was spread onto Brilliance ESBL agar (Oxoid) and incubated at 37°C for 24 h. Matrix-assisted laser desorption ionization–time of flight mass spectrometry  was used for species identification. Susceptibility testing against 13 antimicrobial agents was performed using the disk diffusion method according to CLSI protocols (https://www.bioinformatics.babraham.ac.uk/projects/fastqc/) and LongQC v1.2.0  and 274 Mbp short-read  data using Unicycler v0.4.8 (AVS0096 was isolated in August 2020 from the river Lorze. The water sample 100 ml) was filtered through a 0.45-μm membrane filter (Millipore). The filter was incubated in 10 ml rotocols  and Pore0 ml was r v0.4.8  and annor v0.4.8 . Resistar v0.4.8  and Plasr v0.4.8  databaseH64 clade, as determined using https://pubmlst.org/ and FimTyper v1.0   from E. coli WP3-W18-CRE-03 (ST1193), isolated from wastewater in Japan. According to the CLSI criteria, AVS0096 showed resistance against azithromycin (macrolide), ampicillin, cefazolin, and cefotaxime (β-lactams), ciprofloxacin (fluoroquinolone), streptomycin (aminoglycoside), tetracycline, and trimethoprim-sulfamethoxazole, confirming genotypically identified resistances.The complete genome of AVS0096 consisted of a 4,944,762-bp chromosome and the three plasmids pAVS0096-a , pAVS0096-b , and pAVS0096-c . AVS0096 belonged to the ST1193-per v1.0 , and carVS0096-a . A near-CP076344.1 (chromosome), CP076345.1 (plasmid pAVS0096-a), CP076346.1 (plasmid pAVS0096-b), and CP076347.1 (plasmid pAVS0096-c). The raw data were deposited in the NCBI Sequence Read Archive (SRA) under BioSample accession number SAMN19493560 and BioProject accession number PRJNA734472.The complete genome sequence of AVS0096 has been deposited in GenBank under the accession numbers


Candidemia is the second most common cause of healthcare-associated bloodstream infections in the US with mortality of approximately 25%. Studies demonstrate lower candidemia mortality with infectious diseases consultation (IDC). We evaluated effects of IDC on mortality and guideline-adherence at our institution to determine if mandatory IDC was warranted.Candida) between 1/1/2016-12/31/2019. Exclusion criteria included age < 19 years, polymicrobial blood culture, or death or hospice within 48 hours. Primary outcome was all-cause 30-day mortality. Secondary outcomes included guideline-adherence and treatment choice. Guideline-adherence was assessed with a modified EQUAL Candida score (Table 1). Descriptive statistics were performed.We retrospectively reviewed adults hospitalized with candidemia  were present in 66 (71.7%) patients and were the most common infection source (N=38 [41.3%]) followed by intra-abdominal (N=23 [25%]). The most isolated species were Candida glabrata (40/94 [42.6%]) and C. albicans/dublienensis (35/94 [37.2%]). 30-day mortality was 21.7%. IDC was performed in 84 (91.3%) cases. Outcomes are in Table 3. Mortality was not different between IDC vs no IDC (18 [21.4%] vs 2 [25%]); other comparisons were numerically different but not significant: repeat blood culture (98.8% vs 87.5%), echocardiography (70.2% vs 50%), CVC removal (91.7% vs 83.3%), and initial treatment echinocandin (67.9% vs 50%). All patients received antifungal therapy. IDC resulted in more ophthalmology consultations . Mean modified EQUAL Candida score was higher with IDC .Of 187 patients reviewed, 92 episodes of candidemia with 94 species of Table 2. Patient CharacteristicsAbbreviations. TPN: total parenteral nutrition, ICU: intensive care unit, AIDS: acquired immunodeficiency syndromeTable 3. OutcomesAbbreviations. NS: non-significant, CVC: central venous catheterIDC was common in candidemic patients and not associated with significant differences in outcomes. Current antimicrobial stewardship and consultation practices at our center do not warrant mandated IDC for candidemia.Trevor C. Van Schooneveld, MD, FACP, BioFire  Involved: Self): Consultant, Scientific Research Study Investigator; Insmed  Involved: Self): Scientific Research Study Investigator; Merck  Involved: Self): Scientific Research Study Investigator; Rebiotix  Involved: Self): Scientific Research Study Investigator