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powdery mildew

noun

Definition of powdery mildew

1 :an ascomycetous fungus (family Erysiphaceae) producing abundant powdery conidia on the host
2 :a plant disease caused by a powdery mildew

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First Known Use of powdery mildew

1889

Learn More about powdery mildew

  1. Britannica.com: Encyclopedia article about powdery mildew

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