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The purpose of the current study was to estimate immunity of the winter grain varieties sown in the south of Russia to the pink snow mold pathogen (Microdochium nivale (Fr.) Samuels & I.C. Hallett) in the sprouting phase. For resistance to M. nivale there have been studied 35 winter wheat varieties sown in the south of the Russian Federation, 19 winter barley varieties and 4 variety samples and 13 winter triticale varieties developed in the LLC “Agrostandart”, FSBSI RCG named after P.P. Lukyanenko, FSBSI FRC Kabardino-Balkarian Research Center of the RAS, FSBSI “ARC Donskoy”, FSBSI “North Caucasian FRSC”, FSBSI “FRAC”, NPO “KUBANZERNO”, FSBEI HE “KubSAU”. There has been substantiated a methodological approach to conducting research on immunological estimation of winter grain varieties in the laboratory conditions. The optimal temperature for the cultivation of the pathogen was +10/+15 °C (with a photoperiod of 12 hours). There was found that the required temperature to stimulate sporulation was +5 °C. The optimum temperature for the incubation period was +5 °C at 85% humidity. There has been established that the only winter wheat variety ‘Dolya’ had a very high resistance degree to pink snow mold; the varieties ‘Antonina’ and ‘Brigada’ had a high resistance degree; 21 varieties were classified as resistant. M. nivale resistance was demonstrated by 9 winter barley varieties and 3 variety samples (‘Versal’, ‘Iosif’, ‘KA-12’, ‘KA-5/KA-3’, ‘KA-5/KA-1’, ‘Karrera’, ‘Kondrat’, ‘Kubagro-1’, ‘Lazar’, ‘Master’, ‘Romans’, ‘Sarmat’). Among the studied winter triticale varieties, 4 varieties had a very high resistance degree (‘Argus’, ‘Slon’, ‘Tikhon’, ‘Ullubiy’) and 9 varieties had a high resistance degree to pink snow mold pathogen (‘Aznavur’, ‘Argo’, ‘Arioso’, ‘Valentin 90’, ‘Iliya’, ‘Sotnik’,’ Styuard’, ‘Forte’, ‘Khleborob’).

The current trend of winter rye breeding for the conditions of northern agriculture is development of aluminum and acid-tolerant cultivars. Studies were carried out in the central zone of the Kirov region in 1991-2019. The complex natural provocative background was used (aluminum ion content 25.5-26.7 mg/100 g of soil at a pH of salt extract 3.6-3.8; annual epiphytotic development of pink snow mold Microdochium nivale (Fr.). Winter-resistant and adaptive cv. Kirovskaya 89 served as the initial material. A rigid natural provocative background made it possible to select the best plants (500 pieces) that were transplanted in spring to an isolated area. Subsequent negative selections, field and laboratory assessments made it possible to create the Kiprez population. During the period of 1995-2013 population reproduction was carried out on a provocative background and 5 cycles of negative selection with simultaneous study in competitive varietal testing on two soil backgrounds. The first selection cycle contributed to an increase in the yield of the new population under conditions of edaphic stress over the original cv. Kirovskaya 89 by 12.6%; the second and third by 19.5 and 29.3%, respectively. Further selection did not show a significant effect. Since 2010, the further improvement of the cv. Kiprez has been carried out using individual-family selection and paired crosses. A multi-year competitive test (2014-2019) showed the advantage of the cv. Kiprez over the standard and the initial cultivar. The average yield increase to the Kirovskaya 89 variety under conditions of slightly acidic soils (pH − 5.3-5.7; Al3+ − 5.0-6.5) was 0.50 t / ha (Kirov) and 0.75 t/ha (Falenki); in the conditions of edaphic stress − 1.91 t / ha (Falenki). A combination of aluminum- and acid tolerance of the cultivar with drought resistance was revealed. In 2014, with a moisture deficit (31% of the norm) in the grain filling and ripening phase, cv. Kiprez exceeded significantly the cv. Falenskaya 4 (standard) by 0.82 tons/ha (19.1%) in a acidic background; initial cv. Kirovskaya 89 - by 1.97 tons/ha (62.7%). Cv. Kiprez is recommended for cultivation on low-fertile soils in harsh hydrothermal conditions of northern agriculture.

The analysis of the phytosanitary situation in production, selection and seed crops of winter rye in Kirov region for the period from 1999 to 2018 was carried out in order to adjust the tasks of breeding for resistance to the most harmful diseases. The affection of the sowings (spread of the disease), the development of the disease and the area of the affected crops relative to the number of the examined ones were evaluated. The trend in the development of the diseases was established on the basis of a regression analysis of long-term data of the branch of the FSBI Rosselkhozcentr in Kirov region. The annual (100 %) manifestation of snow mold and ergot has been established. Next according to the frequency of manifestation there are root rots and brown rust – 95 %, powdery mildew – 75 %, sclerotinia – 70 %, Fusarium head blight – 70 %, and stem rust – 50 %. A relatively low frequency of manifestation has been observed with septoriose and rhynchosporium – 35 and 30 %. However, taking into account the development of winter rye diseases which exceed the economic threshold of harmfulness (ETH), the studied pathocomplexes have different levels of danger. Thus, the development of brown rust above ETH was diagnosed 13 times within 19 years. The most severe disease development (20.0-52.0 %) was in 2001, 2005, 2009, and 2010; weak - in 2007 (0.8 %), 2017 (1.4 %), 2015 (2.4 %), and 2011 (5 %). The manifestation of powdery mildew above ETH was observed 6 times within 15 years, disease development was at the level of 13.0-53.0 %. The development of septoriose above ETH was diagnosed 6 times within 7 years with the development of disease from 13.5 to 63.0 %. Development of stem rust above ETH was diagnosed 5 times within 10 years with the status of the sign of 15.0-20.0 %. The cyclicity of spread of the most harmful diseases and trends of their change in agrocenoses of winter rye are shown. Thus, the most epitphytotically dangerous diseases include snow mold, brown rust, stem rust, powdery mildew and septoriose. Constant control is also required in relation to ergot and Fusarium head blight. These diseases should be an object for breeding-and-immunological studies.

Speckled snow mold caused by Typhula ishikariensis is one of the most devastating diseases of winter wheat in Hokkaido, Japan and parts of the Pacific Northwest region of USA. Munstertaler is a winter wheat landrace from Switzerland that has very high resistance to snow mold and superior freezing tolerance. Quantitative trait loci (QTL) for resistance to speckled snow mold were identified in a doubled haploid population derived from a cross between Munstertaler and susceptible variety Ibis, both under field conditions and controlled environment tests. Composite interval mapping analysis revealed a major QTL on chromosome 5D from Munstertaler, and on chromosome 6B from Ibis. Flanking microsatellite marker cfd 29 for the QTL on chromosome 5D was about 5 cM distant from vernalization requirement gene Vrn-D1, suggesting that the QTL on chromosome 5D is located on a cold-stress-related gene cluster along with Vrn-D1 and freezing tolerance gene Fr-D1. The QTL on chromosome 6B from Ibis was located on the centromere region flanking QTn.mst-6B, which is reported to increase plant tiller number.

The aim of the study was to establishdistribution of pink snow mold on turfgrass and to improve the measures for disease control. The crop survey was carried out in the Polissya, Forest-Steppe and Steppe areas. For the identification of pathogens, a selection of plant samples was carried out with further analysis in laboratory conditions. Experiments were carried out during 2015-2018 on the lawn mixture "Universalna". The effect of fungicides of various chemical groups and their mixtures was investigated. Treatment was carried out prophylactically in the fall before installing the snow cover. The assessments were performed according to generally accepted methods; disease spread, disease severity and technical efficiency of pesticides were determined. Symptoms of pink snow mold were fixed annually with a large variation in the spread and severity of disease. Its highest development was recorded in the Zhytomyr region during the vegetative period 2017/2018 , which is associated with a longer period of snow cover. The use of fungicides and their mixtures significantly reduced the number of infected plants, but the protective fungicidal action varied. The most effective was the use of a tank mixture of fungicides Maxim 025 FS (0.4-0.75 l/ha) with Horus 75 WG (0.3-0.6 kg/ha). The average level of fungicidal action was demonstrated by Horus 75 WG, Amistar Gold 250 SE and Amistar Extra 280 SC - 51.4-60.5%. In addition, due to the decrease in the disease development, positive effect on the formation of the quality of the lawn was achieved, projective coverage increased from 62 to 86%. During 2015-2018, the results of the monitoring of the emergence and development of diseases showed that turfgrass was annually affected by snow mold. Development of the disease reached 14,7-26,4%. Preventive spraying of grass in the autumn period protects plants against pink snow mold in the spring. Under application of a mixture of fungicides Maxim 025 FS + Horus 75 WG high level protection was obtained. Depending on the flow rates it varied from 85.3 to 91.5%. Projective coverage thus increased from 62% to 80-86%.

In the conditions of the Kirov region, the major factor reducing the productivity of winter crops is infestation with snow mold (Microdochium nivale (Fr.) Samuels et. Hallet. - synonym Fusarium nivale (Fr.) Ces.), which annually grows by 80-100%. Therefore, the main direction of breeding is receiving winter rye varieties having maximum resistance to this disease. During the period of 2003-2017 there was carried out the assessment of zoned and perspective cultivars of domestic breeding of various ecological-and-geographical origin for snow mold infestation in natural provocative conditions. Weather conditions differed greatly in all periods of rye development. It has been established that plant resistance to M. nivale pathogen is influenced greatly by the condition of plants before wintering regulated by the sowing time. Well-developed plants of Falenskaya 4 variety formed the optimum density of an agro-phytocenosis, accumulated bigger amount of sugars (more than 7%), regenerated during spring re-growth by more than 90%, and produced stable high yield (more than 4.9 t/ha). In order to realize the biological potential of the variety, there was a need to shift the previously established sowing time to 5-10 days later period. The productivity was influenced greatly by April conditions, namely, by the period of total clearing of sowings from snow, which took only several days (3-6). Warm and dry weather favored an active re-growth of rye and prevented disease development. Cold and damp weather provoked fungus development, which affected quickly the plants weakened after rewintering. It was revealed that winter rye varieties of different ecological-and-geographical groups responded to this disease differently. The variability in productivity of each cultivar by years was high (CV = 25.8…65.4%). The greatest stability was characteristic for varieties bred in FARC North-East. The main methods of breeding for the resistance to snow mold are crossing and selection in the conditions of a provocative background. The efficiency of a selection method is confirmed with creation from Falenskaya 4 a highly winter-hardy variety Flora with active regeneration after snow mold infestation (100%) and stable productivity by years – 4.62 t/ha (addition yield to an initial cultivar was 0.27 t/ha). The distinctive feature of Flora variety is active formation of powerful green mass in spring that is important for the early use for green forage for cattle and poultry. Since 2012 the variety is included in the State Register of breeding achievements in Volga-Vyatka and North-West regions of the Russian Federation.

Results 10 years' (2008-2017) comparative studying of varieties of winter rye with recessive-polygenic (the first group) and dominant- monogenic (the second group) short-stem type are presented. In each group tested 5 varieties which estimated on 6 traits: productivity, winter hardiness, plant height, weight is 1000 grains, number of falling and viscosity of water extract of grain meal. Determined by each trait: stability of a phenotype (SF), ecological variation (CV), ecological plasticity (bi), general (GAА) and specific (SAА) adaptive ability, selection value of a genotype (SVG). Average productivity on groups of varieties was identical (respectively 6,69 and 6,62 t/ha), however varieties with dominant-monogenic type of a short-stem differed authentically in the best winter hardiness of plants (for 6,3%) and had shorter stalk (on 9,3 cm). On the ecological variation of traits was influenced significantly by all three factors: weather conditions of year (75,5-95,0%), variety genotype (1,1-2,5%) and interaction variety x years (2,9-22,3%). The most strongly weather conditions of year influenced a productivity variation (86,3% for the first group and 95,0% for the second). On the trait of winter hardiness force of influence of a factor a variety x years was higher, than on other traits, and made respectively 9,3 and 22,3%. Ecological stability at varieties of the second group was twice higher (CV=12,4%), than at varieties of the first group (CV=24,3%). The conclusion is made that varieties of winter rye with a dominant-monogenic short-stem have lower norm of reaction to the adverse conditions of a rewintering developing in years with a high snow cover. Therefore regions where the main limiting factor is the low rewintering because of strong defeat of plants a snow mold have to be the main area of cultivation of such varieties of winter rye. The opinion is expressed that in the main winter rye regions of Russia it is expedient to cultivate varieties of winter rye with different types of a short-stem, but taking into account their agroecological specifics.

In 2001-2017 in the conditions of Kirov region 36 winter rye varieties were assessed according to the character of interrelation in a "Secale cereale - Claviceps purpurea" pathosystem. The article provides the results of this research. For assessment of the change in meteorological conditions and their influence on ergot development the average daily air temperature and amount of precipitations from May 1 to May 31 (the period of screrotia germination) and from June 5 to June 15 (the period of plants infection) were used. The study of varieties was carried out by artificial inoculation of flowers with pathogen suspension. The ergot recording was carried out at a phase of milk-wax ripeness of grain according to infection of biocenoses (quantitative trait) and on contamination of grain mass with sclerotia (qualitative trait). At an artificial inoculation all rye varieties under study were infected by ergot in limits from 8.3 up to 100% that demonstrated their strong susceptibility to disease. Only 6 varieties (Falenskaya 4, Kirovskaya 89, Rada, Flora, Dymka, and Volkhova) were infected at the level of 8.3-27.3%, contamination of grain mass by sclerotia – 0.4-1.9%. The standard variety Falenskaya 4 had a high productivity and efficiency of plants (660 g/m2 and 11.0 g), which was characterized by a high degree of re-growth after infestation with a snow mold (100%), the smallest distribution of an ergot in sowing and contamination of grain mass with sclerotia. During the correlation analysis a close relation between the infestation of plants with an ergot and contamination of grain mass with sclerotia (r = 0.76) was established. The same immunological traits significantly influenced on the productivity (r = -0.67 and -0.55) and insignificantly - on plants efficiency. The positive dependence between immunological traits and 1000-grain mass was revealed. Possibly, sterilization of an ear leads to formation of a larger grain in fertile flowers (r = 0.42 and 0.37). The regression equations between the amount of sclerotia in an ear, mass of grain per ear and a number of grains in it have proved with 95-97% probability that with 1 sclerotium increase in contamination per ear, the grain mass per ear decreases by 0.18 grams, and the amount of grains per ear – by 4.7 pieces.

In northern regions, annual and perennial overwintering plants such as wheat and temperate grasses accumulate fructan in vegetative tissues as an energy source. This is necessary for the survival of wintering tissues and degrading fructan for regeneration in spring. Other types of wintering plants, including chicory and asparagus, store fructan as a reserve carbohydrate in their roots during winter for shoot- and spear-sprouting in spring. In this review, fructan metabolism in plants during winter is discussed, with a focus on the fructan-degrading enzyme, fructan exohydrolase (FEH). Plant fructan synthase genes were isolated in the 2000s, and FEH genes have been isolated since the cloning of synthase genes. There are many types of FEH in plants with complex-structured fructan, and these FEHs control various kinds of fructan metabolism in growth and survival by different physiological responses. The results of recent studies on the fructan metabolism of plants in winter have shown that changes in fructan contents in wintering plants that are involved in freezing tolerance and snow mold resistance might be largely controlled by regulation of the expressions of genes for fructan synthesis, whereas fructan degradation by FEHs is related to constant energy consumption for survival during winter and rapid sugar supply for regeneration or sprouting of tissues in spring.

Snow mold is a severe plant disease caused by psychrophilic or psychrotolerant fungi, of which Microdochium species are the most harmful. A clear understanding of Microdochium biology has many gaps, the pathocomplex and its dynamic are poorly characterized, virulence factors are unknown, genome sequences are not available, and the criteria of plant snow mold resistance are not elucidated. Our study aimed to identify comprehensive characteristics of a local community of snow mold-causing Microdochium species colonizing a particular crop culture. By using the next-generation sequencing (NGS) technique, we characterized fungal and bacterial communities of pink snow mold-affected winter rye (Secale cereale) plants within a given geographical location shortly after snowmelt. Twenty-one strains of M. nivale were isolated, classified on the basis of internal transcribed spacer 2 (ITS2) region, and characterized by morphology, synthesis of extracellular enzymes, and virulence. Several types of extracellular enzymatic activities, the level of which had no correlations with the degree of virulence, were revealed for Microdochium species for the first time. Our study shows that genetically and phenotypically diverse M. nivale strains simultaneously colonize winter rye plants within a common area, and each strain is likely to utilize its own, unique strategy to cause the disease using &ldquo, a personal&rdquo, pattern of extracellular enzymes.

Propiconazole is often used to remove fungal endophytes from turfgrass to study the effects of Epichloë endophytes. However, besides a fungicidal effect, propiconazole can bind to the genes in the cytochrome P450 family and affect the biosynthesis of brassinosteroids. For this reason, outside of fungicidal application, propiconazole has also been used as plant growth regulator. In this study, we used a combination of RNA sequencing and liquid chromatography–mass spectrometry (LC-MS) to study how hard fescue (Festuca brevipila) responded to the high dose of propiconazole treatment. To test the long-term effect of the heavy use of propiconazole on plants, we inoculated with Microdochium nivale (causal agent of pink snow mold) half year post the last fungicide application. Propiconazole-treated plants showed enhanced pink snow mold resistance. This study suggested that the high dose use of propiconazole fungicide resulted in phenotypic and physiological changes in the plant such as slow growth and change in disease resistance. Genes and pathways affected by propiconazole identified in this study provide turfgrass breeders new information for genetic improvement of hard fescue and also provide turfgrass management new ways to control turfgrass diseases.

Snow mold is a severe plant disease caused by psychrophilic or psychrotolerant fungi, of which Microdochium species are the most harmful. A clear understanding of Microdochium biology has many gaps; the pathocomplex and its dynamic are poorly characterized, virulence factors are unknown, genome sequences are not available, and the criteria of plant snow mold resistance are not elucidated. Our study aimed to identify comprehensive characteristics of a local community of snow mold-causing Microdochium species colonizing a particular crop culture. By using the next-generation sequencing (NGS) technique, we characterized fungal and bacterial communities of pink snow mold-affected winter rye (Secale cereale) plants within a given geographical location shortly after snowmelt. Twenty-one strains of M. nivale were isolated, classified on the basis of internal transcribed spacer 2 (ITS2) region, and characterized by morphology, synthesis of extracellular enzymes, and virulence. Several types of extracellular enzymatic activities, the level of which had no correlations with the degree of virulence, were revealed for Microdochium species for the first time. Our study shows that genetically and phenotypically diverse M. nivale strains simultaneously colonize winter rye plants within a common area, and each strain is likely to utilize its own, unique strategy to cause the disease using “a personal” pattern of extracellular enzymes.

Winter wheat (Triticum aestivum L.) undergoes a period of cold acclimation in order to survive the ensuing winter, which can bring freezing temperatures and snow mold infection. Tolerance of these stresses is conferred in part by accumulation of carbohydrates in the crown region. This study investigates the contributions of carbohydrate accumulation during a cold treatment among wheat lines that differ in their snow mold tolerance (SMT) or susceptibility (SMS) and freezing tolerance (FrT) or susceptibility (FrS). Two parent varieties and eight recombinant inbred lines (RILs) were analyzed. The selected RILs represent four combinations of tolerance: SMT/FrT, SMT/FrS, SMS/FrT, and SMS/FrS. It is hypothesized that carbohydrate accumulation and transcript expression will differ between sets of RILs. Liquid chromatography with a refractive index detector was used to quantify carbohydrate content at eight time points over the cold treatment period. Polysaccharide and sucrose content differed between SMT and SMS RILs at various time points, although there were no significant differences in glucose or fructose content. Glucose and fructose content differed between FrT and FrS RILs in this study, but no significant differences in polysaccharide or sucrose content. RNAseq was used to investigate differential transcript expression, followed by modular enrichment analysis, to reveal potential candidates for other mechanisms of tolerance, which included expected pathways such as oxidative stress, chitinase activity, and unexpected transcriptional pathways. These differences in carbohydrate accumulation and differential transcript expression begin to give insight into the differences of wheat lines when exposed to cold temperatures.

Aipova R, Abdykadyrova A, Silayev D, Tazabekova E, Oshergina I, Ten E, Kurmanbaye A. 2020. The fabrication of the complex bio-fertilizer for wheat cultivation based on collection bacteria of the PGPR group. Biodiversitas 21: 5021-5028. The development of new types of biological products based on microbial complexes from local bacterial strains is a great theoretical and practical interest for agriculture. It can provide an opportunity for better preservation of the natural properties of the wheat products under extreme conditions. The aim of this study was to obtain and test a biological product to increase wheat productivity in northern Kazakhstan. Our data indicate the potential of Plant Growth-Promoting Rhizobacteria (PGPR) group bacteria for the development of biofertilizers and biopesticides. For instance, the bacteria B. mojavensis showed effectiveness in the experiments with the wheat (Astana-2 type). We observed an increase in wheat yield by 15% under conditions of artificial infection of crops with snow mold (by 2.5fold compared with the control). The results demonstrated that the B. mojavensis Lhv 97 strain can be used as an ingredient of biological products due to its activity against plant diseases caused by phytopathogenic fungi.

Key messageSnow mold resistance is a complex quantitative trait highly affected by environmental conditions during winter that must be addressed by resistance breeding.AbstractSnow mold resistance in winter cereals is an important trait for many countries in the Northern Hemisphere. The disease is caused by at least four complexes of soilborne fungi and oomycetes of whichMicrodochium nivaleandM. majusare among the most common pathogens. They have a broad host range covering all winter and spring cereals and can basically affect all plant growth stages and organs. Their attack leads to a low germination rate, and/or pre- and post-emergence death of seedlings after winter and, depending on largely unknown environmental conditions, also to foot rot, leaf blight, and head blight. Resistance in winter wheat and triticale is governed by a multitude of quantitative trait loci (QTL) with mainly additive effects highly affected by genotype × environment interaction. Snow mold resistance interacts with winter hardiness in a complex way leading to a co-localization of resistance QTLs with QTLs/genes for freezing tolerance. In practical breeding, a multistep procedure is necessary with (1) freezing tolerance tests, (2) climate chamber tests for snow mold resistance, and (3) field tests in locations with and without regularly occurring snow cover. In the future, resistance sources should be genetically characterized also in rye by QTL mapping or genome-wide association studies. The development of genomic selection procedures should be prioritized in breeding research.

Purpose. Analysis of winter rye varietal resources formation for Ukrainian producers. Results. Rye varieties (Secale cereale L.) were analyzed for a number of economically valuable traits and resistance to abiotic factors. Accor­ding to the yield data in the zones of Steppe, Forest-Steppe and Polissia, one can see that the variety of foreign selection occupies the leading place. The analyzed cultivars are early maturing, what allows to get crops in a shorter time. The State Register of Plant Varieties includes plants which were 100–140 cm in height. The mass of 1000 grains of all analyzed varieties was 32–34 g. The protein content in grains of varieties ranged from 9 to 12%. High rates of resistance to abiotic factors, such as droughts, and undesirable events like lodging and shedding, allow growing these varieties in all soil-climatic zones on the territory of Ukraine. It is worth noting that the varieties have a high resistance to powdery mildew and snow mold. The State Register of Plant Varieties includes 43 varieties of winter rye as of August 10, 2018. Varieties that are listed in the State Register of Plant Varieties suitable for distribution in Ukraine have high rates of resistance to abiotic factors, what is the basis for their inclusion in the Registry.Conclusions. A detailed study and analysis of the resistance of plant varieties to stress factors allows us to assess them thoroughly. In addition to the assessment of frost and winter resistance, drought and heat resistance of field crops, it is necessary to assess the cold resistance, resistance to winter thaws, asphyxiation, ice crust, rotting and other adverse factors. Such analysis will allow a better description of new varieties and the selection of those that in addition to high yields, are resistant to abiotic factors. In climate changes it will allow obtaining high yields of winter rye.

Insufficient yield capacity potential of varieties is one of the reasons for decrease in areas and production of winter rye grain. Creation of productive varieties adaptable to region conditions is possible with the use of modern sources of breeding-valuable traits that meet demands of growing conditions. The purpose of the research was to assess the yield capacity of 578 varieties of the world gene pool and 86 varieties of domestic selection in the conditions of the Kirov region and to select the sources of breeding-valuable traits. Studies were done in 1996-2015. During the study in collection nursery 9 varieties with yield capacity at the level of standard Falenskaya 4 (400 g/m 2 ) were selected: Zhatva, Nadezhda, Narymskaya 89 (Russian Federation); Feya (Belarus); Lira, Pallada (Ukraine); SСW 1662 (Germany); (k-11060) local (Finland); Suceava 317/76 (Romania). Nine sources of valuable traits on the density of productive plant stand (> 371 pcs./m 2 ) were selected; 15 - on ear productivity (> 19 g), 23 - on the grain size (weight of 1000 grains >36 g). The following varieties of domestic breeding have high potential of yield capacity: Purga, Tatyana, NVP-3, Pamyat' Kondratenko, Grafinya, Rushnik, Tatarskaya 1, Estafeta Tatarstana, Era, Volkhova, Roksana, Populyaciya BC, Chulpan 7, Pamyati Kunakbaeva. Heavy-productive varieties (variety Era had the maximum yield capacity - 8.28 t/ha) in some years suffer significantly or even completely die at overwintering during the period of snow mold (Microdochium nivale) epiphytoty. Varieties bred in Russia Pamyat Kondratenko, Chulpan 7, Populyaciya AC, Marusen'ka, Irina, Antares, Volna, Radon', Tatarskaya 1, Saratovskaya 6, Saratovskaya 7, Kirovskaya 89, Snezhana, and Krona can be recommended as a source of high ear productivity. Eight sources of large grains and 12 sources of grain number in an ear have been selected. Work collection of gene sources for use in modern winter rye breeding programs of the North-East breeding center has been formed.

There were studied the peculiarities of fungal diseases of triticale and spelt in the conditions of Ukrainian Polissia. It was found that Septoria leaf blotch and powdery mildew have a dominant role in the pathogenic complex of both cultures as their relative shares are 34.0 and 23.0% respectively in the complex of triticale leaf mycoses, and 52.0 and 36.0% respectively in the complex of spelt leaf mycoses. It was noted that such diseases as tan spot, brown leaf rust and snow mold rarely occurred on winter triticale plants, and such diseases as ascochyta leaf blight, spot blotch and Fusarium disease were episodic in nature. Development of tan spot and spot blotch on spelt plants had non-systematic character. It was established that on spelt wheat level of disease severity is lower and number of pathogens is less

The article presents an analysis of the distribution and development of pink snow mold (pathogenMicrodochium nivale(Fr.) Samuels & I.C. Hallett) on winter cereal crops in the Republic of Belarus and in the South of Russia. Pink snow mold is currently one of the most harmful diseases of winter cereal crops, as it can cause damage not only to various parts of the plants, but also lead to their complete death. The intensity of the disease development mainly depends on weather conditions in the autumn-spring period, namely, on the duration of snow cover, its height and the rate of melting in spring. We determined the dependence of the disease development progress on agroclimatic conditions. There is a description of weather conditions in combination with a gradation of the disease development level in the Republic of Belarus and in Krasnodar Krai (southern Russia) during the epiphytotic and depressive years of the pink snow mold development. The article provides a retrospective analysis of the crops infected with pink snow mold and the treated cereal crops in southern Russia in 2011 -2019.

Snow mold is a yield-limiting disease of wheat in the Pacific Northwest (PNW) region of the US, where there is prolonged snow cover. The objectives of this study were to identify genomic regions associated with snow mold tolerance in a diverse panel of PNW winter wheat lines in a genome-wide association study (GWAS) and to evaluate the usefulness of genomic selection (GS) for snow mold tolerance. An association mapping panel (AMP; N = 458 lines) was planted in Mansfield and Waterville, WA in 2017 and 2018 and genotyped using the Illumina® 90K single nucleotide polymorphism (SNP) array. GWAS identified 100 significant markers across 17 chromosomes, where SNPs on chromosomes 5A and 5B coincided with major freezing tolerance and vernalization loci. Increased number of favorable alleles was related to improved snow mold tolerance. Independent predictions using the AMP as a training population (TP) to predict snow mold tolerance of breeding lines evaluated between 2015 and 2018 resulted in a mean accuracy of 0.36 across models and marker sets. Modeling nonadditive effects improved accuracy even in the absence of a close genetic relatedness between the TP and selection candidates. Selecting lines based on genomic estimated breeding values and tolerance scores resulted in a 24% increase in tolerance. The identified genomic regions associated with snow mold tolerance demonstrated the genetic complexity of this trait and the difficulty in selecting tolerant lines using markers. GS was validated and showed potential for use in PNW winter wheat for selecting on complex traits such tolerance to snow mold.

Climate change is reducing the depth and duration of winter snowpack, leading to dramatic changes in the soil environment with potentially important ecological consequences. Previous experiments in the Intermountain West of North America indicated that loss of snowpack increases survival and population growth rates of the invasive annual grass Bromus tectorum; however, the underlying mechanism is unknown. We hypothesized that reduced snowpack might promote B. tectorum population growth by decreasing damage from snow molds, a group of subnivean fungal pathogens. To test this hypothesis, we conducted greenhouse and field experiments to investigate the interaction between early snowmelt and either fungicide addition or snow mold infection of B. tectorum. The greenhouse experiment confirmed that the snow mold Microdochium nivale can cause mortality of B. tectorum seedlings. In the field experiment, early snowmelt and fungicide application both increased B. tectorum survival, but their effects did not interact, and snow mold inoculation had no effect on survival. We did find interactive effects of snowmelt and fungal treatments on B. tectorum seed production: with ambient snowpack, M. nivale inoculation reduced seed production and fungicide increased it, whereas in the early snowmelt treatment seed production was high regardless of fungal treatment. However, treatment effects on seed production did not translate directly to overall population growth, which did not respond to the snow melt by fungal treatment interaction. Based on our mixed results, the hypothesis that reduced snowpack may increase B. tectorum fitness by limiting the effects of plant pathogens deserves further investigation.

Climate change is reducing the depth and duration of winter snowpack, leading to dramatic changes in the soil environment with potentially important ecological consequences. Previous experiments in the Intermountain West of North America indicated that loss of snowpack increases survival and population growth rates of the invasive annual grass Bromus tectorum; however, the underlying mechanism is unknown. We hypothesized that reduced snowpack might promote B. tectorum population growth by decreasing damage from snow molds, a group of subnivean fungal pathogens. To test this hypothesis, we conducted greenhouse and field experiments to investigate the interaction between early snowmelt and either fungicide addition or snow mold infection of B. tectorum. The greenhouse experiment confirmed that the snow mold Microdochium nivale can cause mortality of B. tectorum seedlings. In the field experiment, early snowmelt and fungicide application both increased B. tectorum survival, but their effects did not interact, and snow mold inoculation had no effect on survival. We did find interactive effects of snowmelt and fungal treatments on B. tectorum seed production: with ambient snowpack, M. nivale inoculation reduced seed production and fungicide increased it, whereas in the early snowmelt treatment seed production was high regardless of fungal treatment. However, treatment effects on seed production did not translate directly to overall population growth, which did not respond to the snow melt by fungal treatment interaction. Based on our mixed results, the hypothesis that reduced snowpack may increase B. tectorum fitness by limiting the effects of plant pathogens deserves further investigation.