Downy Mildew

Jump to: Symptoms of Downy Mildew Facts Life Cycle of Downy Mildew Management of Downy Mildew

Symptoms of Downy Mildew

downy mildew

downy mildew

Downy mildew, or crazy top, causes distortion and/or stunting of the corn plant.
Tunneling usually kills the plant.
The tassel bracts may proliferate, resulting in a very bushy appearance of the top of the plant.

Facts

Downy mildew is a fungal disease that frequently occurs in areas of fields subject to flooding.
Seedlings are more susceptible than adult plants.

Life Cycle of Downy Mildew

Crazy top is caused by a soilborne fungus, which overwinters as oospores either within infected tissue or in the soil.
During periods of flooding, the oospores germinate and swimming zoospores are produced. The zoospores infect the growing point of the young corn plants.

Management of Downy Mildew

Avoiding areas prone to flooding and providing for adequate drainage of surface water are the best means of controlling downy mildew.