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 diagnosed on agronomic crops during the past week have included Rhizoctonia root rot on alfalfa; glume blotch, speckled leaf blotch, tan spot, and stripe rust on wheat; Pythium root rot, target spot, and cold injury on tobacco transplants.
On fruit and vegetable samples, we have diagnosed Phomopsis leaf blight on strawberry; anthracnose and black rot on grape (Figure 1); cedar-apple rust on apple; fire blight on apple and pear; anthracnose on bean; Pythium root rot and foliar blight on pea; bacterial spot on pepper; potassium deficiency on sweet corn; Botrytis leaf blight and fruit decay, Sclerotinia blight, early blight, and Pythium root rot on tomato.
Ornamental and turf samples included Pythium root rot and high soluble salts on annual vinca; Botrytis blight on petunia; leaf streak on daylily; anthracnose on liriope; anthracnose on ash; frogeye leaf spot on crabapple; chemical injury on rose; and red thread on bluegrass.
By Julie Beale and Brenda Kennedy, Plant Disease Diagnosticians