Inheritance Analysis And Moleculor Mapping To The Stripe Rust Resistance Of Adult XiaoYan 54 In High Temperature

This thesis focus on high temperature resistance to stripe rust of the progenies of Xiaoyan54, and susceptible cultivar, Mingxian169. Genetic analysis, RGAP and SSR techniques are used to study the mode of inheritance of seedling stripe rust resistance in cultivar Xianyan54 and identify the genomic location of gene(s) involved, in order to further cloning and use of its high-temperature adult plant resistance gene(s) in wheat breeding.Xianyan54 was tested with the Chinese predominant races of P. striiformis f. sp. tritici CYR29, CYR30, CYR31, CYR33, Su11-4, and Su11-11 under high temperature, the results showed that Xianyan54 was immune or nearly immune against theses pathotypes.The F1, F2, F3 and F4 progenies of Xianyan54 and Mingxian169 were used for genetic analysis. As for CYR29, the resistance of Xianyan54 was confered by a dominant gene and a ressive gene. The results was consistant with a 3:13 ratio; The resistance against CYR30 and CYR31 were from two ressive genes,respectively. And the ratio was consistant with 1:15; A ressive gene offered the resistance against CYR32, which segregation of resistant to sussceptible fit a 1:3 ratioThe results suggested that the resistantce against CYR32 was conferred by a ressive gene. Using bulked segregant analysis (BSA) and RGAP markers, 4 RGAP pairs(M1(S2-INV,RLRR Rev),M2(S2-INV, Pto kin4),M3(S2-INV, LM637),M4(AS3, S2))were linked to Yrxy54 with genetic distance ranging from 7.3 to 16.6cM. Based on the previously published genetic map and Chinese Spring nulli-tetrasomic analysis, Yrxy54 was located on wheat chromosome 7A.The chromosomal location of Yrxy54 was confirmed by using 21 SSR markers which located on 7A, two SSR, Xbarc49 and Xwmc422, were linked to the taget gene.The genetic distance were 15.1 cm and 26.1 cm, respectively.The mapping of the new resistance gene in Xianyan54 is useful for wheat breeding and diversification of resistance genes against stripe rust in commercial wheat cultivars in China.