Characterization and validation of QTLs for adult plant stripe rust resistance in Chinese wheat landrace Dabaimai

Wheat stripe/yellow rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the serious diseases of wheat. The application of resistance cultivars underpins control of wheat stripe rust. The Chinese wheat landrace Dabaimai displayed resistance to most of the Chinese yellow rust races. To decipher the genetic bases of resistance in Dabaimai, a total of 202 recombinant inbred lines F6 of Taichung 29/Dabaimai were tested under field conditions with a predominant Pst race CYR32. Based on SSR markers and field resistance data, two resistance QTLs were detected and named QYr.caas-1AS and QYr.caas-4BS, respectively. QYr.caas-1AS, located on chromosome 1AS between markers Xgwm136 and Xcfd15, can explain 45.97% and 26.83% of the phenotypic variance for infection type (IT) and disease severity (DS), respectively. QYr.caas-4BS, located on chromosome 4BS between markers Xwmc652 and Xgpw4388, can explain 43.38% and 21.30% of the phenotypic variance for IT and DS, respectively. The adult plant stripe rust resistance loci and linked SSR markers will be valuable in combining with other effective genes for combating wheat stripe rust.