Powdery mildew, caused by Blumeria graminis f. sp. tritici, is one of the most devastating wheat diseases. Wild emmer wheat（Triticum turgidum ssp. dicoccoides） is a promising source of disease resistance for wheat. A powdery mildew resistance gene conferring resistance to B. graminis f. sp. tritici isolate E09, originating from wild emmer wheat, has been transferred into the hexaploid wheat line WE4 through crossing and backcrossing. Genetic analyses indicated that the powdery mildew resistance was controlled by a single dominant gene, temporarily designated Ml WE4. By mean of comparative genomics and bulked segregant analysis, a genetic linkage map of Ml WE4 was constructed, and Ml WE4 was mapped on the distal region of chromosome arm 5BL. Comparative genetic linkage maps showed that genes Ml WE4, Pm36 and Ml3D232 were co-segregated with markers XBD37670 and XBD37680, indicating they are likely the same gene or alleles in the same locus. The co-segregated markers provide a starting point for chromosome landing and map-based cloning of Ml WE4, Pm36 and Ml3D232.
