Powdery mildew—Erysiphe polygoni
Powdery mildew usually appears first as yellow spots on the upper leaf surface of older leaves; these
spots develop the characteristic powdery growth and symptoms spread to the undersides of leaves and stems.
Affected leaves may turn completely yellow, die, and fall off and the fruit beneath may become sunburned.
In most cases, planting resistant varieties or avoiding the most susceptible varieties and following
good cultural practices will adequately control powdery mildew. Plant in unshaded areas as much as possible.
Provide enough water and avoid excess fertilizer. Protection of susceptible varieties with applications
of sulfur may be necessary where conditions are most favorable for mildew.
For more information see the Powdery
Mildew Pest Note.
of powdery mildew on pea