Characterization of Modern Russian Varieties of Spring Soft Wheat for Their Resistance to Yellow Rust

The study has been conducted with the aim of assessing the genetic diversity of commercial varieties of spring soft wheat for resistance to yellow rust to identify their potential for genetic protection against Puccinia striiformis West. The objects of study have been represented by 86 varieties first included in the State Register of Breeding Achievements of the Russian Federation in 2019–2023. To assess seedling resistance, four populations of P. striiformis have been used, which differed from each other in their geographical origin (Leningrad, Dagestan, Krasnodar, and Novosibirsk populations) and virulence to differentiators containing Yr1, Yr2, Yr4, Yr7, Yr27, Yr32, YrSD, and YrN D genes. Only six varieties, or 7% of the whole sampling (Odeta, KWS Jetstream, Nadira, Pexeso, Sviyaga, and Khazine), manifest resistance to all pathogen populations at the seedling stage. Molecular markers have been used to postulate ten Yr genes (Yr5, Yr7, Yr9, Yr10, Yr15, Yr17, Yr18, Yr24, Yr40, and Yr60) and a wheat-rye translocation 1AL.1RS with an unknown Yr gene. Avocet isogenic lines and varieties with identifiable genes have been used as positive controls. No effective Yr5, Yr10, Yr15, Yr24, and Yr40 genes, as well as Yr7 and Yr60 genes with varying effectiveness, have been detected in the studied varieties. Yr9, Yr17, and Yr18 genes and the 1AL.1RS wheat-rye translocation with an unknown Yr gene have been widely presented in the variety sampling. The performed analysis indicates a low genetic diversity of Russian localized spring wheat varieties in relation to the yellow rust resistance and the necessity to conduct advance breeding for resistance to P. striiformis.