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.
It have proved that wheat translocation line H9020-1-6-8-3 derived from Psathyrostachys huashanica Keng is an important resistant resource to stripe rust.To confirm the existence of resistant genes,it was crossed with susceptible cultivar MingXian 169 as male and female parent,respectively.Seedlings of parents and F2 progeny were tested for resistance to selected CY29 of races of Puccinia striiformis f.sp.tritici from China.H9020-1-6-8-3 had one dominant resistant gene which temporarily named YrHs,whatever it was male or female parent.By using BSA method,two markers,Xgwm261 and Xgwm455 located on 2DL were found.The distance to YrHs were 4.3 and 5.8 cM respectively.The result could be used in molecular-assisted breeding.
