Plant Disease Diagnostic Clinic (PDDC) Update 9/13-9/19

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 September 13, 2014 through September 19, 2014.

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


Corn, Common Rust, Puccinia sorghi, Pierce

Corn, Gibberella Stalk Rot, Fusarium graminearum, Rock

Corn, Goss’ Wilt, Clavibacter michiganensis subsp. nebraskensis, Lincoln, Trempealeau

Corn, Gray Leaf Spot, Cercospora sp., Lafayette, Pierce

Corn, Northern Corn Leaf Blight, Exserohilum turcicum, Lafayette, Pierce

Soybean, Brown Spot, Septoria glycines, Eau Claire, Sheboygan

Soybean, Brown Stem Rot, Phialophora gregata, Eau Claire

Soybean, Pod and Stem Blight, Phomopsis sp., Eau Claire, Sauk

Soybean, Soybean Cyst, Heterodera glycines, Eau Claire


Alfalfa, Aphanomyces Root Rot, Aphanomyces euteiches, Marathon

Alfalfa, Fusarium Root Rot, Fusarium sp., Marathon

Alfalfa, Phytophthora Root Rot, Phytophthora sp., Marathon

Alfalfa, Rhizoctonia Root Rot, Rhizoctonia solani, Marathon


Apple, Sphaeropsis Canker, Sphaeropsis sp., Marathon

Apple, Cedar-Apple Rust, Gymnosporangium sp., Sauk

Apple, Scab, Venturia inaequalis, Sauk

Cranberry, Blueberry Shock, Blueberry shock virus, Wood

Cranberry, Tobacco Streak, Tobacco streak virus, Wood

Grape, Anthracnose, Sphaceloma ampelinum, Dodge

Grape, Black Rot, Phyllosticta ampelicida, Dodge


Carrot, Cercospora Leaf Blight, Cercospora sp., Dane

Cucumber, Downy Mildew, Pseudoperonospora cubensis, Calumet

Muskmelon, Anthracnose, Colletotrichum sp., Dane

Pepper, Bacterial Canker, Clavibacter michiganensis subsp. michiganensis, Portage

Pepper, Root Rot, Pythium sp., Portage

Potato, Late Blight, Phytophthora infestans, Unknown

Pumpkin, Downy Mildew, Pseudoperonospora cubensis, Calumet

Tomato, Anthracnose, Colletotrichum sp., Dane

Tomato, Early Blight, Alternaria solanit, Calumet

Tomato, Late Blight, Phytophthora infestans, Brown, Racine

Tomato, Septoria Leaf Spot , Septoria lycopersici, Dane, Racine

For additional information on plant diseases and their control, visit the PDDC website at