UW-Madison/Extension Plant Disease Diagnostic Clinic (PDDC) Update June 12, 2020
The PDDC is now once again accepting physical samples for diagnosis, but due to COVID-19, only with limited hours and limited sample processing capacity. Click here for the current submission policy. The PDDC is continuing to provide diagnoses through examination of digital photographs. Digital diagnoses have not traditionally been included in the Wisconsin Disease Almanac, because such diagnoses are not verified through lab testing (critical in most situations for a diagnosis to be accurate). However, in an attempt to keep clients as informed as possible, digital diagnoses will be included in the Almanac until normal PDDC operations resume. For Almanac entries below, when a digital diagnosis would normally require a lab confirmation, the disease/disorder will be labeled as “suspected”. The following diseases/disorders have been identified at the PDDC from June 6, 2020 through June 12, 2020.
| Plant/Sample Type | Disease/Disorder | Pathogen | County |
| Apple | Frogeye Leaf Spot (Suspected) Gymnosporangium Rust Root/Crown Rot (Suspected) | Botryosphaeria obtusa Gymnosporangium sp. Unspecified root/crown rot fungi/water molds | Rock Dane, Rock Dane |
| Cherry | Bacterial Canker (Suspected) Bacterial Leaf Spot (Suspected) | Pseudomonas syringae Pseudomonas syringae | La Crosse, Waupaca La Crosse |
| Grape | Anthracnose (Suspected) Cold Injury (Suspected) | Sphaceloma ampelinum None | Chippewa Chippewa |
| Mulberry | Wood Rot | Unspecified wood rot fungus | Grant |
| Pear (Unspecified) | Bacterial Canker (Suspected) Cold Injury (Suspected) Peach Leaf Curl Fertility Issues (Suspected) | Pseudomonas syringae None Taphrina deformans None | Dane, Sauk Sauk Dane, Waupaca Dane |
| Raspberry | Spur Blight (Suspected) | Didymella applanata | Dane |
| Strawberry | Common Leaf Spot Phomopsis Leaf Blight (Suspected) | Mycosphaerella fragariae Phomopsis obscurans | Monroe Monroe |
To learn more about plant diseases and their control, as well as PDDC educational resources and activities, visit the PDDC website at pddc.wisc.edu, follow the clinic on Facebook and Twitter @UWPDDC or email pddc@wisc.edu to subscribe to the PDDC listserv “UWPDDCLearn”.
This article was posted in Disease and tagged Cherry, diseases, mulberry, PDDC, pear, Plant Disease Diagnostic Clinic.