Background. Structuring and phenotyping genetic diversity is an important aspect of the work with breeding sources and materials. In the Introduction, the authors pointed out the role of N.I. Vavilovs scientific foresight in defining the topical trend in researching the genetic diversity of a crop, particularly the analysis of its biochemical composition. As the target of their research, the authors chose biochemical characters identifiable in the process of metabolomic analysis conducted by means of gas chromatography with mass spectrometry. Materials and methods. The object was the grain of naked and covered forms of common oat (Avena sativa L.) from the collection held by the Oat, Rye and Barley Genetic Resources Department of VIR. The analysis of oil fatty acid content and metabolomic research were performed using the method of gas-liquid chromatography with mass spectrometry on the chromatograph Agilent 6850 (USA). Results. The obtained metabolomic spectra which reflected the metabolomic status of genotypes of various ecogeographic origin were compared among themselves using statistical (principal component) analysis methods. The results of the comparison are discussed by referring to the most important groups of metabolites significant for forming the traits of resistance to stressors as well as the characters related to food qualities of grain products. Special attention has been paid to biologically active compounds determining the functional value of the products for human nutrition: the sum of phenolics in covered forms is five times higher than that in naked ones and the content of glycine amino acid in covered forms is five times higher than in naked grain, with a similar proportion in the content of organic acids, sugars, etc. Conclusion. Differences between metabolomic profiles of naked and covered forms have been detected and statistically verified. Accessions with the most optimal nutritional composition have been identified for food purposes and for the development of resistance to biotic and abiotic environmental stresses.

Under conditions of climate change, the assessment of the stability of genotypes is of particular importance. To conduct directed selection of genotypes with a narrow or broad reaction rate, it is necessary to assess their stability already in the early stages of breeding. The aim of the study was to study the stability of breeding significant traits of oat and barley samples in contrasting ecological and geographical conditions. 25 oat samples and 25 barley samples were studied over 3 years under contrasting conditions in St. Petersburg and the Tambov region. Varieties are characterized by average values of economically valuable traits and genotype regression coefficients on the influence of the bi environment according to Eberhart and Russell. The most sensitive to a change in the ecological and geographical situation were the durations of the germination-heading, germination-harvest periods and grain yield. These characters varied to a greater extent depending on the cultivation conditions than on the genotype. According to regression coefficients for environmental conditions, significant differences in genotypes were only in yield. Contrasting groups of varieties were distinguished by regression coefficients on environmental conditions, genotypes with high productivity. The durations of germination-heading, germination-harvest, the plant height reacted to the change in the environment the same in different varieties. The duration of the growing season was determined by the sum of effective temperatures above 15C. The reduction of the growing season in both crops was 3 days with an increase in the sum of effective temperatures above 15C by 100C.

Sixty six genotypes belong to wild and cultivated Avena species from the VIR collection were evaluated for infection of grain by Fusarium fungi and mycotoxins in accumulation. Among genotypes 13.6, 28.8, and 57.6% were diploid, tetraploid, and hexaploid oats, respectively. The aim of this study was to recognize the interrelationship between the wild species of the genus Avena not subjected to formal breeding programs, and Fusarium fungi, which have been reported as predominant seed borne pathogens. The real-time PCR was used to simultaneously detect and quantify fungi in grain of Avena genotypes. Mycotoxin analysis was performed by ELISA. The average amount of Fusarium DNA and deoxynivalenol (DON) in groups of the tetraploid oats were higher than they were found in the groups of di- and hexaploid species. It was determining the strong correlation between the presence of Tri-Fusarium DNA and DON content (p < 0,01). The low amounts of DON in the grain were detected in seven hexaploid genotypes (A. byzantina, A. sterilis, A. sativa, and A. fatua) and one diploid A. wiestii. The connection of morphological characters (weight of 1000 grains, husk hardness, trichomes profusion and plant height) of Avena species and the indicators of Fusarium infection were analyzed. Only biomass of Fusarium has demonstrated significant connection with weight of 1000 grains. Significant correlation between the hardness of husk and the amounts of Fusarium DNA (p < 0,01) was detected. For Fusarium the strong protective effect of the husk from the penetration of pathogens into grain was evident.