Powdery Mildew

Erysiphe cichoracearum, Sphaerotheca fuliginea

Symptoms:
Powdery mildew is a fungal disease that affects most cucurbits, and in fact, many other species as well. Infection is first noted as slightly chlorotic spots on leaves. A white powdery appearing "dust" quickly covers the leaf surface, and affected leaves gradually turn brown and papery.

Control:
Use of resistant varieties and/or preventative fungicide sprays are both important. Since the fungus also infects many weed species, good weed control in and around production fields is important. Disease development is favored by cool, dry weather.

See also the Texas Plant Disease Handbook.

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