Abstract Powdery mildew, caused by Blumeria graminis f. sp. tritici, is one of the most important wheat diseases worldwide. Application of resistance varieties is the most economical and effective method for controlling this disease. The common wheat line 3D256, a derivative of wild emmer (Triticum dicoccoides) with pedigree Yanda1817/WE27//Nongda015/3/941, is highly resistant to prevailing local wheat powdery mildew isolate E09 in Beijing area. Genetic analysis of the F2 population and their F3 families, developed from 3D256 and a susceptible common wheat cultivar Xuezao, indicated that the powdery mildew resistance in 3D256 was controlled by a single dominant gene, designated temporarily MlWE27. Molecular markers and the bulked segregant analysis were used to characterize the powdery mildew resistance gene MlWE27. Three SSR markers (Xwmc243、Xwmc154 and Xbarc318), one EST-SSR marker (Xdp358), one AFLP-derived SCAR markers (XCAUG1) and one RFLP-derived STS marker (XWG516-1) were found to be linked to the powdery mildew resistance gene MlWE27, with an order of Xdp357-MlWE27-Xwmc243-XCAUG1-XWG516-1-Xwmc154-Xbarc318 in the genetic linkage map. Using Chinese Spring nullisomic-tetrasomics, ditelosomics and deletion lines, MlWE27 was physically mapped on chromosome 2BS terminal bin 0.84-1.00. The new developed common wheat powdery mildew resistance line 3D256 and its resistance gene linked molecular markers provide useful germplasm and tool in disease resistance genes pyramiding and marker-assisted selection (MAS) in wheat breeding program.
