UW-Extension/Madison Plant Disease Diagnostic Clinic (PDDC) Update

Brian Hudelson, Ann Joy, Amy Gibbs, and Brooke Weber, Plant Disease Diagnostics Clinic

The PDDC receives samples of many plant samples from around the state. The following diseases/disorders have been identified at the PDDC since August 5, 2009:

PLANT/SAMPLE TYPE	DISEASE/DISORDER	PATHOGEN	COUNTY
FIELD CROPS
Soybeans	Brown Spot   Growth Regulator Herbicide Damage   Root/Crown Rot	Septoria glycines   None     Fusarium sp., Pythium sp.	Sauk   Buffalo     Monroe, Sauk
FRUIT CROPS
Grape	Guignardia Leaf Spot/ Black Rot	Guignardia bidwellii	Dodge
VEGETABLES
Beet	Root Rot	Fusarium sp., Pythium sp., Rhizoctonia sp.	St. Croix
Cucumber	Cucumber Mosaic   Tobacco Mosaic	Cucumber Mosaic Virus   Tobacco Mosaic Virus	Fond du Lac   Fond du Lac
Eggplant	Verticillium Wilt	Verticillium sp.	Racine, Vernon
Onion	White Rot	Sclerotinia cepivorum	Dickinson (MI)
Tomato	Bacterial Canker     Growth Regulator Herbicide Damage   Late Blight   Septoria Leaf Spot   Tobacco Mosaic   Tomato Spotted Wilt   Walnut Toxicity	Clavibacter michiganensis subsp. michiganensis   None     Phytophthora infestans   Septoria lycopersici   Tobacco Mosaic Virus   Tomato Spotted Wilt Virus   None	Grant     Dane     Dane   Clark   Iowa   Iowa   Grant

For additional information on plant diseases and their control, visit the PDDC website at pddc.wisc.edu.