Assistance requested to identfy damage or disease on grapes. - Ask Extension
These symptoms started on some grapes near the end of last week and the condition is spreading fast. There was a Pylon application four weeks ago to...
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Assistance requested to identfy damage or disease on grapes. #546647
Asked March 11, 2019, 2:58 PM EDT
These symptoms started on some grapes near the end of last week and the condition is spreading fast. There was a Pylon application four weeks ago to manage spider mites and nothing since, so I don't think it's related to the spray. Plus, other types of plant material were treated with Pylon the same night with no subsequent damage.
The condition is only in the middle of the plants. So far the upper juvenile leaves and lowest leaves are not affected. Any ideas would be helpful.
Thank you,
Dahlia
Ontario County New York
Expert Response
Hi Dahlia - what variety are they? My first instinct was downy mildew, but I don't think that's it. I can stop by the greenhouse sometime next week and take a look with you if you'd like.
