The following plant disease highlights from the University of Kentucky Plant Disease Diagnostic Laboratories represent recent sample submissions from field crops, fruit, vegetables, and ornamentals.
Diseases and other problems diagnosed on agronomic crops during the past two weeks have included southern rust on corn; anthracnose, web blight (Rhizoctonia), and summer black stem/leaf spot on alfalfa; Cercospora leaf spot on hemp; sudden death syndrome, frogeye leaf spot, soybean cyst nematode, anthracnose, stem canker, root mealybug, and soil compaction on soybean; black shank, frogeye leaf spot, and hollow stalk on tobacco.
On fruit and vegetable samples, we have diagnosed Phomopsis leaf blight and anthracnose on strawberry; anthracnose and bitter rot on grape; bitter rot on apple; scab on pecan; Cercospora leaf blight on asparagus; downy mildew on basil; powdery mildew and downy mildew on squash; southern blight on pepper; and bacterial spot on tomato.
Ornamental and turf samples included Pythium root rot, web blight, and bacterial spot on chrysanthemum; Cercospora leaf spot on zinnia; anthracnose, Actinopelte leaf spot, powdery mildew, and bacterial leaf scorch on oak; anthracnose on maple; brown patch, rust and anthracnose on fescue.
By Julie Beale and Brenda Kennedy, Plant Disease Diagnosticians