Any remaining fresh market sweet corn should be sprayed on a 2-3 day silk spray schedule until the end of the season. Powdery mildew has been identified in New Jersey and New York this summer infecting field grown tomatoes. Previously powdery mildew had been seen only in greenhouse production and just within the last two years in New York. Infected tomato leaves are chlorotic and the fungus produces white, talcum-like growth typical of the powdery mildews on the lower leaf surfaces. Powdery mildew is certainly a common disease on the eastern shore, but not on tomatoes.
Powdery mildew is more common in the western growing regions.
It has been reported that Bravo provides control if complete coverage of the leaves can be obtained. Be on the lookout for this new disease on tomatoes. Please let the county agents know if you spot this disease in Delaware either in commercial production or in home gardens. If there is any question concerning identification of powdery mildew, place infected leaves in a zip-lock bag and submit samples to the county agents or myself at 154 Townsend Hall, Newark, DE 19717. Be on the lookout for bean rust .