Genetic Analysis Of Stripe Rust Resistance Gene In Wheat Varieties Shan515, Xiaoyan016 And Xianyan9366

Stripe rust is one of the most important wheat diseases worldwide. To identify new resistance genes is significant in wheat breeding. In this study, the Chinese land race cultivar Shan515, Xiaoyan016 and Xiaoyan9366 were tested with Chinese predominant races of P. striiformis f. sp. tritici in the seedling stage, and genetic analysis of the gene(s) confered resistance against the PST pathotypes in three different wheat cultivars were researched.The progenies of Shan515×Mingxian169, F2population, tested with Sun11-11, CYR29 and CYR33, the resistance of Shan515 were confered by two recessive gene, respectively. A single dominant gene was confered resistance against CYR30. Shan515 carries two dominant genes against CYR.31.F2, F3, and BC1F1 of Shan515×Mingxian169 tested with Sun11-4, the genetic analysis indicated that the resistance of Shan515 against Sun11-4 was conferred by a single dominant gene, which was temporarily designated as Yr515. Using bulked segregant analysis (BSA) and SSR markers,12 SSR markers(Xwmc335, Xwmc696, Xwmc476, Xbarc267, Xgwm333, Xwmc653, Xwmc396, Xgwm213, Xgwm112, Xgwm274, Xcfd22, Xgwm131 and Xwmc517) located on wheat chromosome 7BL were linked to Yr515 with genetic distance ranging from 3 to 24 cM. Based on the previously published genetic map and Chinese Spring nulli-tetrasomic analysis, Yr515 was located on wheat chromosome 7BL. Polymorphism of wheat cultivars from Huanghuai wheat grown region were screened with two markers, Xwmc653 and Xbarc267, and all of these wheat cultivars did not present the polymorphic bands as Shan515 did. Therefore, it suggested that Yr515 might be a novel gene. The mapping of the new resistance gene in Shan515 is useful for wheat breeding and diversification of resistance genes against stripe rust in commercial wheat cultivars in China.The genetic analysis of Xiaoyan016 inoculated with seven predominant Chinese PST pathotypes, Xiaoyan016 carries more than one resistance gene against each PST pathotypes. As for CYR31 and CYR32, the resistance of Xiaoyan016 was confered by two dominant genes. The resistance against Sun11-4 and CYR33 were from a dominant gene and two ressive genes, respectively. Three dominant genes offered the resistance against Sun11-11. when tested with CYR29, the result was that a dominant gene and a ressive gene conferred the resistance against it. Based on the Xiaoyan9366 tested with nine Chinese PST pathotypes, the results was that Xiaoyan9366 was susceptible to four Chinese PST races, which were predominant in the area from 2002, but Xiaoyan9366 was resistant to five Chinese PST pathotypes. The results suggests that the resistance of Xianyan9366 for CYR30 and CYR31 was confered by a dominant gene, respectively. The resistance against CYR25 and Sun11-4 was obtained from a dominant gene and a ressive gene. When tested with CYR27, two dominant genes invovled offered resistance of Xianyan9366.