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Related to powdery mildew: downy mildew
1. Any of various plant diseases caused by fungi, especially of the family Erysiphaceae, that produce powdery conidia on the host surface.
2. A fungus causing such a disease.
1. (Plant Pathology) a plant disease characterized by a superficial white powdery growth on stems and leaves, caused by parasitic ascomycetous fungi of the family Erysiphaceae: affects the rose, aster, apple, vine, oak, etc
2. (Plant Pathology) any of the fungi causing this disease
1. any of various fungi of the ascomycete order Erysiphales that produce a powderlike film of mycelium on the surface of host plants.
2. the plant disease caused by powdery mildew.