The high yield potential of winter wheats cannot be realized due to disease pressure under field conditions. One of the most harmful of such diseases is stem rust, hence the constant search for sources of resistance and the development of new varieties resistant to stem rust is of great relevance. This study deals with the identification of stem rust resistance genes in a collection of winter wheats grown in Southern Russia. This genepool has not been studied yet. A total of 620 samples of winter soft wheat from various ecological and geographical zones were tested under field conditions. To identify the specific genes or alleles responsible for resistance, all samples were genotyped using PCR. As a result, the groups of resistant samples, carrying the Sr2, Sr31, Sr38 and Sr44 genes in various combinations, were identified. Most of the stem rust resistance was provided by the presence of the effective Sr44 gene. This information can be used in the future breeding work for stem rust resistance.

Salt tolerance of rice is of great importance in agricultural production, since productivity of grain grown on saline lands largely depends on it. The paper deals with determining the presence of salt tolerance gene “Saltol” in rice hybrids obtained from crossing contrasting samples. To analyze salt tolerance, there were used seeds germinated in cups with distilled water and 1.5% NaCl solution, after which 10-day-old seedlings were weighed and their ratio to the control was determined. As a result of studies, there have been identified salt tolerant lines carrying the gene “Saltol” in a homozygous state. In the control nursery there were studied the best samples on productivity and elements of its structure. Two lines “7328” and “7322” were selected from the hybrid IR 52713-2B-8-2B-1-2 x Novator which significantly exceeded the standard variety “Yuzhanin” on 0.57-1.28 t/ha. On average for 2 years, they produced 6.82-7.53 t/ha (6.25 t/ha of the standard variety).

There have been studied physical, flour-milling, technological features of the grain of the new varieties and lines of winter soft wheat developed by the FSBSI “Agricultural Research Center “Donskoy”. The purpose of the study is to identify samples with high quality of grain, flour, rheological properties of dough and baking profits. High values of grain unit and general vitreousness of grain are revealed. The samples “1237/13” (14.6%), “1261/13” (14.5%) and “Nakhodka” (14.5%) formed protein content at the level of strong wheat of the 1st class (not less than 14.5%). The varieties “Tanais” (30.9%), “Aksiniya” (30.2%), “Nakhodka” (29.5%), “Donskaya step” (28.6%) and the line “1261/13” (28.4%) showed high content of gluten in the grain of the 2nd class of quality. The studied varieties and lines of winter wheat were characterized by a high yield of flour, more than 70%. The maximum yield of flour was obtained in the variet­ies “Tanais” (74.5%), “Ermak” (74.1%) and the line “1261/13” (74.2%). According to the color, the flour of the samples (54.0–80.0 con­ventional units) “Aksiniya” (55.64 conv. units), “Nakhodka” (55.18 conv. units), “Kipchak” (54.01 conv. units), “Bonus” (54.90 conv. units), “Kazachka” (54.40 conv. units) and the line “1261/13” (54.30 conv. units) corresponded to the highest grade. There were identi­fied variety differences in flour color and ash content, which the quality of the end product largely depends on. The 6 studied varieties “Yubiley Dona” (342 u. a.), “Nakhodka” (311 u. a.), “Shef” (292 u. a.), “Kipchak” (290 u. a.), “Tanais” (289 u. a.) and “Aksiniya” (289 u. a.) showed high rheological properties of the dough at the level of strong wheat. There were identified the samples with high yield of bread “Nakhodka” (705 ml), “Aksiniya” (695 ml) and “Donskaya Step” (685 ml), which corresponded to the class of strong wheat. The identi­fied varieties and lines can be used in the breeding process as the sources with high grain quality and baking properties.

Nowadays one of the priorities in winter soft wheat breeding is to provide resistance to leaf diseases, and, in particular, to leaf rust as the most harmful of them. The gene for resistance to leaf rust, Lr34, provides resistance to wheat plants at the slow development. The use of this gene together with other genes for resistance to leaf rust will allow obtaining varieties and samples less susceptible to the disease. The purpose of this work was to identify the Lr34 gene in the varieties and collection samples of winter soft wheat in the Agricultural Research Center "Donskoy" (ARC "Don skoy"), because its presence was suspected due to the introduction of the variety "Bezostaya 1" in hybridiza tion of the 1960s, but the study of this gene in our collection has not been carried out yet. The article gives the results of the study of 646 samples of winter soft wheat (including 36 varieties of ARC "Donskoy" introduced in the State Register of Breeding Achieve ments of the Russian Federation and 8 varieties being tested in the State Variety Testing) and identification of the Lr34 gene and its allelic state. The assessment of the allelic state of the Lr34 gene has been carried out with the help of the codominant marker csLV34 using the method of PCR. There have been identified 238 samples with the Lr34 gene in the dominant allelic state. The varieties Nakhodka,

Grain sorghum (Sorghum bicolor (L.) Moench) is one of the major crops used for various purposes, including animal and human nutrition. The most relevant strategy for creating new sorghum hybrids is the use of lines with cytoplasmic male sterility (CMS). However, the process of creating sterile lines and lines that restore fertility is very laborious and time-consuming. The breeders need to know the genotype of the original parental forms of sorghum by the presence of the main genes that control fertility to speed up breeding work. One of these is the Rf1 gene. Our study aimed to identify alleles of the Rf1 gene in collection samples of grain sorghum (Sorghum bicolor (L.) Moench) adapted to the arid conditions of southern Russia. The studies were carried out in southern Russia (FSBSI “ARC “Donskoy”, Zernograd, Russia) between 2018–2019. The presence of alleles of the Rf1 fertility gene using the Xtxp18 SSR marker by PCR analysis in collection samples of grain sorghum (313 pcs.) was studied. Some samples were crossed with two sterile lines: “Demetra S” and “Dzhetta S” (developed in FSBSI “ARC “Donskoy”) in 2019. The assessment of the fertility of self-pollinated lines was carried out in the field using a 3-point scale. The polymorphism of the Xtxp18 marker allowed for the identification of a wide allelic diversity of the Rf1 gene in collection samples of sorghum, and the association of the identified Rf1 alleles with the fertility and sterility of self-pollinated hybrids of grain sorghum as a result of the study was performed. This result will make it possible to deepen understanding of the influence of the Rf1 gene alleles on the level of fertility of sorghum plants in the future, as well as to accelerate the breeding process to create sterile lines and their fertile analogues for further obtaining commercial hybrids.

In order to obtain high yields of winter durum wheat, it is necessary not only to use advanced agricultural technologies, but also to sow varieties resistant to major diseases. One of these diseases that cause great harm to grain crops is Septoria leaf blotch. The current paper has presented the study results of collection material of Russian and foreign winter durum wheat according to the efficiency of the Septoria leaf blotch resistance gene Stb2 in the North Caucasus region. The purpose of the current study was to identify the Septoria leaf blotch resistance gene Stb2 in the collection material of winter durum wheat. The study was carried out in 2017–2018 in the laboratory of marker breeding of the FSBSI “ARC “Donskoy” in Zernograd. In the course of the study there have been applied such methods as the isolation of genomic DNA by the CTAB-method, PCR-analysis with the molecular SSR marker WMS533, electrophoresis on 2% agarose gel, analysis of electrophoresis gels in the Bio-Rad Image Lab 6.0 software, general data analysis by Microsoft Excel. The study has shown that 29 samples out of 185 analyzed ones had the Septoria leaf blotch resistance gene Stb2, they are the lines L3557 h42, L3182 h7, L3335 h29, L3336 h43, L3408 h218 (Russia, FSBSI “Research Center of Plants named after P. P. Lukyanenko”), K-61620 (Russia), K-54455, DF 917 (Romania), K-61924, K-59179, K-51863, K-61869 (Moldova), K-63871 (Turkey), Kharkovskaya 909 (Ukraine), MVTD-15-99 (Hungary), 2196-1/04, 922/93, 589/13, 655/13, 683/13, 145/14, 322/14, 484/14, Gordeiform 1424/82 (Russia, FSBSI “ARC “Donskoy”), Beliy Parus (Ukraine), Belgorodskaya Yantarnaya (LLC “Sativa” in Belgorod, Russia), IR named after V. Ya. Yuriev (Kharkov, Ukraine)), Zhivitsa (Russia, Prikumskaya OSS), Pandur (Romania) and Elidur (Romania). There have been recommended using the identified samples of winter durum wheat with the Septoria leaf blotch resistance gene Stb2 in breeding programs.

Nowadays in Russia and in the world, the problem of improving food security is becoming more and more urgent. One of the main crops grown worldwide is winter bread wheat. Varieties resistant to main leaf diseases can produce large grain yields. Thus, the study and identification of resistance genes are of great importance. The purpose of the current work was to estimate the gene pool of winter bread wheat from the CIMMYT collection (Mexico) according to the age brown rust Lr 34 resistance gene. In the study of collection samples, there have been used such methods as DNA extraction using CTAB, PCR, electrophoresis on agarose gels. As a result of the study, there has been identified a presence of a functional allele of the Lr 34 gene in 146 winter bread wheat samples out of 411 studied ones (sets 20th IWWYT-SA, 21th IWWYT-IRR, 25th FAWWON-IRR, 25th FAWWON-SA). There have been identified three samples with a heterozygous allelic state of the Lr 34 gene. There have been identified 232 samples with the non-functional Lr 34 gene allele. 30 winter bread wheat samples had no amplification of DNA fragments with the molecular marker csLV34, which means a significant microsatellite sequence variability for which the molecular marker was developed in their genotype. 121 out of 146 winter bread wheat samples with the functional brown rust Lr 34 resistance gene showed resistance in field conditions and in the infectious plots. The rest 25 samples with the Lr 34 gene belonged to the group of moderately resistant ones in the infectious plots. The identified 121 CIMMYT collection winter bread wheat varieties, with the Lr 34 gene possessing a resistant type of pathogen damage response (for example, 9919, 9921, 9928, 9809, 9811, 9812, 23, 24, 30, 262, 265, 266, etc.) have been recommended for use in leaf rust resistance pyramiding in future breeding programs.

One of the main problems in most of the world rice-growing regions is soil salinity. Rice is considered a saline sensitive crop, especially at the early stages of development and in the period of maturity. In the Rostov region, rice is grown in the south-eastern parts, where there are currently difficulties with the operation of the existing reclamation facilities. The problem of saline soils for this region is especially urgent, since a significant part of the arable lands has alkali complexes. In order to return the saline lands into exploitation, it is necessary to develop salt tolerant varieties, which, under crop rotation and maintenance, can contribute to soil desalinization. Due to the difficulty of determining salt tolerance only by estimating the phenotype, it is necessary to use molecular markers associated with this trait. Thus, the purpose of the current work was to identify one of the main Saltol QTL in breeding rice samples of the eighth generation (F8) obtained from hybridizing the donor variety NSYC Rc106 with Russian varieties. For that purpose, there have been used such marker-assisted selection methods as DNA isolation, polymerase chain reaction (PCR), electrophoresis on 2% agarose gels, gels’ coloring in ethidium bromide solution, photography in ultraviolet light and evaluation of the obtained electrophoregrams. As a result of the study of 398 breeding rice samples, there have been identified 67 samples with the functional allele of Saltol QTL (6865/3, 6874/2, Don 7343/4, Don 7343/5, Don 7343/6, Don 7343/7, Don 7343/8, Don 7343/9, Don 7343/10, Don 7337/1, Don 7337/3, Don 7337/4, Don 7337/5, Don 7337/6, Don 7337/7, Don 7337/8, etc.). There have been recommended to use these samples in the further breeding process in order to develop new salinity resistant rice varieties.