Screening of leaf rust resistance genes (Lr) in the breeding lines of winter bread wheat

In the Rostov region, among cereal crops, winter wheat occupies a leading position in terms of the sown area. Breeders have developed wheat varieties, a productivity potential of which is 1.5–2 times higher than their actual yield in production. One of the most important factors that can destabilize gross grain harvests and reduce productivity are parasitic organisms, the most dangerous of which are rust pathogens (Puccinia triticina, P.striiformis, P.graminis). Brown rust (pathogen Puccinia triticina Erikss.) is one of the dangerous wheat diseases. The genetic diversity of cultivated varieties according to resistance types and genes that control it, provides reliable wheat protection against this pathogen. The purpose of the current study was to identify leaf rust resistance genes (Lr-genes) using marker selection for the winter bread wheat lines. The study was carried out in 2020–2021. The objects of research were 311 winter bread wheat lines of the FSBSI Agricultural Research Center «Donskoy». In the study of winter bread wheat lines, there were used such methods as DNA isolation using CTAB, PCR, and electrophoresis on agarose gels. Using molecular markers, there have been identified 24 samples with a functional allele of the Lr10 gene (1672, 518/21 (1), 595/21 (1) 595 (4), 625/21, 626/21, etc.), 49 samples with the dominant allele Lr26 (1105, 502/21, 526/21 (1), 526/21 (2), 529/21 (12), 557/21, etc.), 13 lines with the resistance allele of the Lr37 gene (1105, 1609, 1610, 1611, 1612, 1613, 1615, etc.). There was also found that the Lr17a gene was not detected in the studied lines.