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

Brian Hudelson, Ann Joy, Joyce Wu, Tom Hinsenkamp, and Catherine Wendt, Plant Disease Diagnostics Clinic

The PDDC receives samples of many plant and soil samples from around the state. The following diseases/disorders have been identified at the PDDC from July 19, 2014 through July 25, 2014.

Plant/Sample Type, Disease/Disorder, Pathogen, County


Soybean, Bacterial Blight, Pseudomonas savastanoi pv. Glycinea, Lafayette

Soybean Bacterial Blight, Cercospora Blight, Cercospora kikuchii, Washington

Soybean Bacterial Blight, Downy Mildew, Peronospora manshurica, Washington

Soybean Bacterial Blight, Phytophthora Root Rot, Phytophthora sp., Lafayette


Alfalfa, Aphanomyces Root Rot, Aphanomyces euteiches,, Vernon, Allamakee (IA)

Alfalfa, Root/Crown Rot, Fusarium sp., Pythium sp., Rhizoctonia sp., Vernon, Allamakee (IA)


Apple, Root Rot, Pythium sp., Door

Apple, Sphaeropsis Canker, Sphaeropsis sp., Jackson, Marinette

Apple, Winter Injury, None, Door, Jackson,

Cherry, Powdery Mildew, Oidium sp., Dane

Cranberry, Protoventuria Early Leaf Spot, Protoventuria sp., Wood

Grape, Downy Mildew, Plasmopara viticola, Dane


Beet, Cercospora Leaf Spot, Cercospora beticola, Fond du Lac

Cabbage, Black Rot, Xanthomonas campestris, Outagamie

Garlic, Fusarium Basal Plate Rot, Fusarium oxysporum, Jackson

Onion, Fusarium Basal Plate Rot, Fusarium oxysporum, Jackson

Onion, Stemphylium Leaf Blight, Stemphylium sp., Green Lake

Tomato, Septoria Leaf Spot, Septoria lycopersici, Dane

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