Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu
The rain we have had has also been favorable for powdery mildew which is a minor disease of tomato in fields that have not been sprayed. It is more common in backyard gardens and can result in defoliation. For commercial growers apply Rally or Cabrio at the first sign of disease and repeat every 14 days.
Powdery mildew on tomato