Marquette fruit rots
What is the best pesticide and how often do I need to use it for grapevines specifically Marquette varietyI have used a generic pesticide and continue to have fruit rotAs the great Ripens
Livingston County Michigan
There are 4 major grape diseases; black rot, phomopsis, downy mildew and powdery mildew. Marquette is fairly resistant to them all. It is susceptible to anthracnose. Unfortunately, there is no one fungicide that controls all these diseases. Do you know which one is causing you problems? You can look at the different diseases at our grape website Here is a link to the disease page. https://www.canr.msu.edu/grapes/integrated_pest_management/
Let me know which is your problem disease and I can help you more.
If you think it is anthracnose let me know. You might want to read this document from the retired grape disease specialist in New York. https://doubleavineyards.com/Images/2015%20Anthracnose_Wilcox.pdf