Blumeria graminis is an ascomycete fungus responsible for powdery mildew in a variety of grasses, including economically important cereals such as barley and wheat, causing falls in yields of up to 40%. Its genome exhibits considerable variability, allowing the evolution of strains that are able to infect previously resistant crop varieties, or that exhibit fungicide resistant. There are two strains available in Ensembl Genomes:

Blumeria graminis f. sp. hordei and Blumeria graminis f. sp. tritici .