UW-Madison/Extension Plant Disease Diagnostic Clinic (PDDC) Update July 3, 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 27, 2020 through July 3, 2020.
| PLANT/SAMPLE TYPE | DISEASE/DISORDER | PATHOGEN | COUNTY |
| FRUIT CROPS | |||
| Apple | Canker Disease Gymnosporangium Rust Lichens | Unspecified canker fungus Gymnosporangium sp. None | Dunn Monroe Shawano |
| Cherry | Prunus Necrotic Ringspot (Suspected) | Prunus necrotic ringspot virus | Marathon |
| Grape | Downy Mildew (Suspected) Fertility Issues (Suspected) | Plasmopara viticola None | Ozaukee Ozaukee |
| Pawpaw | Cold Injury (Suspected) | None | Dane |
| Peach | Bacterial Canker (Suspected) Peach Leaf Curl | Pseudomonas syringae Taphrina deformans | Kenosha Kenosha |
| Pear | Pear Scab (Suspected) | Venturia pirina | Dane, Waupaca |
| Raspberry (Unspecified) | Root/Crown Rot (Suspected) | Unspecified root rot fungi/water molds | Brown |
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 Apples, Berries, Disease, Grapes and tagged Apples, bacterial canker, canker disease, Cherry, cold injury, Downy mildew, fertility issues, Grapes, gymnosporangium rust, lichens, Pawpaw, PDDC, Peach, peach leaf curl, pear, pear scab, Plant Disease Diagnostic Clinic, prunus necrotic, Raspberries, ringspot, Root/Crown Rot.