Vegetable Disease Update – September 2, 2011

Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu

Cucurbit Downy Mildew
Cucurbit downy mildew was confirmed on pumpkin, summer squash and winter squash this week in DE. It will likely be more widespread following the storm. Maintain fungicide sprays specific for downy mildew if the foliage is still green and harvest is still planned.

Late Blight
Late blight was reported in a central New York county this past week on tomatoes in a homeowners garden. After the hurricane we might see some late blight develop on tomatoes.

Lima Bean Downy Mildew
Be sure to scout for lima bean downy mildew after the hurricane. Symptoms may take 7-10 days to develop after the rain ended. See previous issues for recommendations, or the 2011 Commercial Vegetable Production Recommendations.