M8657-1,one of the wheat translocation lines derived from Leymus mollis Trin.Hara,is possessed of effective resistance at all stages to Su-11 and other dominant races of Puccinia striiformis f.sp.tritici in China.Seedlings of the parents,F1,and F2 progeny derived from the cross of M8657-1(resistant)Ming-xian169(susceptible)were inoculated with Su-11 in greenhouse to identify and map the probable new stripe rust resistance gene.The results suggested that the stripe rust resistance in M8657-1 was conferred by a pair of recessive genes.Simple sequence repeat(SSR)technique was used to detect molecular marker associated with the resistance gene:208 pairs of wheat SSR primers were used to screen the two parents,as well as resistant and susceptible bulks and then three SSR markers were selected for genotyping the F2 population.The gene,temporarily designated as YrLm1,was found to be located on the chromosome 7DL and flanked by three SSR markers GDM67,WMC150 and WMC671,with the genetic distance of 5.0,9.7 and 11.8cM,respectively.