LAUSR

Diseases of crops are the main reason for the decrease in yield and product quality. Blast is the most dangerous disease in all areas of world rice cultivation. The most effective, economically viable, and environmentally friendly strategy to combat it is the development of resistant varieties. The use of molecular genetic markers (DNA markers) linked to the loci of blast resistance is relevant in this direction. The objective of the study was to introgress and pyramid genes effective in the south of Russia for race-specific resistance to blast Pi ta, Pi-b, Pi-1, Pi-2, Pi-33, Pi-40 into the genotypes of highly productive rice varieties of domestic breeding to obtain new forms resistant to P. oryzae. To achieve this, varieties Flagman and Boyarin were hybridized with the donors of resistance to blast IR-36, Bl-1, C101-Lac, C101Lac-A-51, IR 83260-2-10-5-2-1-B, which have the genes Pi-ta, Ρi-b, Pi-1 + Pi-33, Pi-2, Pi-40, respectively, with a growing season of more than 150 days. Three backcrosses were carried out and the breeding material was obtained. Several samples with high rates of milled rice quality and blast resistance, productivity, and other economically valuable traits were identified. The program for combining the genes of resistance to blast was performed. The hybridization of the obtained genotypes with the integrated Pi genes between themselves in their various combinations was carried out. The result was a breeding variety with three resistance genes (Pi-1; Pi-2; Pi-33). The cultivation of such varieties in production will reduce the use of chemical protective equipment and avoid pollution of grain ecosystems.