Genetics and Molecular Mapping of Stripe Rust Resistance Gene YrShan515 in Chinese Wheat Cultivar Sh

Stripe rust is one of the most important wheat diseases worldwide. To identify new resistance genes is significant in wheatbreeding. In this study, stripe rust resistance of a Chinese cultivar Shan 515 was tested with Chinese predominant racesof P. striiformis f. sp. tritici in the seedling stage, and genetic analysis and simple sequence repeats (SSR) technique wereused to identify the inheritance model of seedling stripe rust resistance in cultivar Shan 515 and to mark the sites ofresistance gene(s) on chromosome. The genetic analysis indicated that the resistance of Shan 515 against Su11-4 wasconferred by a single dominant gene, which was temporarily designated as YrShan515. 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 toYrShan515 with genetic distance ranging from 3 to 24 cM. Based on the previously published genetic map and ChineseSpring nulli-tetrasomic analysis, YrShan515 was located on wheat chromosome 7BL. Polymorphism of wheat cultivarscollected from Huanghuai wheat grown regions were screened with two markers, Xwmc653 and Xbarc267, and all of thesewheat cultivars tested did not present the polymorphic bands as Shan 515 did. Therefore, it suggested that YrShan515might be a allele of the available yellow rust resistance gene. The mapping of the new resistance gene in Shan 515 is usefulfor wheat breeding and diversification of resistance genes against stripe rust in commercial wheat cultivars in China.