Plant Disease Diagnostic Lab Highlights

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.

Recent agronomic samples have included Rhizoctonia stem canker on alfalfa; gray leaf spot, northern leaf blight, and southern rust on corn; Phytophthora root/stem rot and sudden death syndrome on soybean; Cercospora leaf spot and Pythium root rot on hemp; black shank, hollow stalk, frogeye leaf spot, target spot, tomato spotted wilt virus, tobacco streak virus, drowning, manganese toxicity, and boron deficiency on tobacco.

On fruit and vegetable crops, we have seen Botryosphaeria canker on blueberry; leaf blight (Isariopsis) on grape; downy mildew on basil; anthracnose, bacterial wilt, Fusarium fruit rot, and belly rot (Rhizoctonia) on cantaloupe; downy mildew and powdery mildew on cucumber; bacterial spot on pepper; early blight, Septoria leaf spot, Fusarium wilt, and tomato spotted wilt virus on tomato; angular leaf spot on zucchini; and anthracnose on watermelon.

On ornamentals and turf, we have diagnosed Pythium root rot, bacterial spot and Fusarium wilt on chrysanthemum; bacterial spot on begonia; Phoma canker/dieback on vinca; anthracnose, web blight and Phoma leaf spot on hydrangea; Verticillium wilt on redbud; Botryosphaeria canker on arborvitae and rhododendron; copper spot on bentgrass; and brown patch on fescue.

 

By Julie Beale and Brenda Kennedy, Plant Disease Diagnosticians

 

Posted in Plant Disease Diagnostic Lab