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Objectives: To understand the genetic mechanism of stripe rust resistance inJimai 22,map the resistant gene(s)and identify molecular markers closely linked for marker-assisted selection.Methods: Fifteen F1,377F2 plants and 127 F2-derived F2:3 lines from Avocet S/Jimai 22 cross were evaluated for rust resistance with CYR32.Seedling test were conducted under controlled greenhouse conditions as Li et al.(2006)described previously.Totally 1680 SSR markers were screened on the two parents and the resistant and susceptible bulks.Markers showing polymorphisms between the resistant and susceptible parents and the respective bulks were used to genotype the entire F2 population for linkage analysis.The Yr1-specific marker stm673acag was used to test the parents to discriminate Yr1 and YrJ22(Bansal et al.2009).The resistant and susceptible DNA bulks were genotyped with the IlluminaInfinium Wheat 90K iSelectBeadChip.SNPsshowing polymorphism between the resistant and susceptible bulks on chromosome 2AL were used to genotype the 377 F2 plants for linkage analysis byKASP technique(Semagn et al.2014)following the manufacturers manual.Results: Stripe rust resistance inJimai 22 was conferred by a single dominant gene,temporarily designated YrJ22.A linkage map was constructed with five SSR and two SNP markers on 2AL.Xwmc658 and IWA1348 flanked YrJ22 at genetic distances of 1.0 and 7.3 cM,proximally and distally,respectively.Seedling reactions to 21 Pstraces demonstrated differences in specificity betweenYrJ22 and other resistance genes on chromosome2AL,indicating that YrJ22 is different in specificity from Yr1 and Yr32.Conclusions: YrJ22 is likely to be a new stripe rust resistance gene.The current information on chromosomal location of YrJ22 and linked markers should be useful for developing stripe rust-resistant cultivars,preferably having combinations of two or more effective resistance genes.