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Powdery mildew caused by Blumeria graminis f.sp.tritici (Bgt) is one of the most important wheat diseases worldwide.Breeding resistant cultivars are the most economical, effective and environmentally safe method to prevent the epidemic outbreaks of powdery mildew.Spelt wheat (Triticum aestivum ssp.spelta (T.spelta)2n=6X=42, AABBDD) is a close relative of common wheat, contains several known disease resistance genes, including Pm1d, Yr5, Lr65, etc.Here we report the identification and mapping of powdery mildew resistance gene in spelt wheat cultivar Hubel, Hubel was resistant to Bgt race E09 at seedling stage.Genetic analysis by the segregation of resistance and susceptibility among a recombinant inbred lines (RILs) population derived from a cross of Hubel with its early mature mutant line 2463, indicated that Hubel possessed a single powdery mildew resistance gene (temporarily designated MlHubel).MlHubel was suggested to be recessive since the F1 plants of Hubel and susceptible cultivar Liaochun10 was susceptible.By bulked segregant analysis (BSA), we have identified polymorphic simple sequence repeats (SSR),expressed sequence tags (EST) derived sequence tagged site (STS) markers linked to MlHubel.The linked markers were physically located on wheat chromosome 2D.Comparative genetic analyses indicated that the genetic interval covering MlHubel in wheat is highly co-linear with the corresponding regions on Brachypodium distachyon chromosome 5, and the Oryza sativa chromosome 4.This colinearity enabled us to develop new and closer EST-STS markers of MlHubel.The genetic map of MlHubel provides the initial step for fine mapping, chromosome landing and map-based cloning of the powdery mildew resistance gene.Moreover, the developed conserved markers closely linked to MlHubel can be used for the marker-assisted selection (MAS) of MlHubel in wheat breeding programs.