Whats wrong with my grapes?

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Bev Campbell

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I have a 100 year old bine in a vinery. My 2nd year with it. Had slight mildew last year and sprayed with bordeax mix in spring. Yesterday they looked great .... got up today to this. Pretty much every bunch affected. Also strange white an pink long growths from trunk about 4 ft up. Is anything salvegable? Gratefully for any ideas and advice. X20210719_182759.jpg20210719_182751.jpg20210719_182742.jpg20210719_182730.jpg
 
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I am thinking its phomopsis. The leaves look ok so its not powdery mildew. Mancozeb can treat it. Dont know of its too late.
 
Don't forget that there's a 66 day interval between spraying and harvest with mancozeb. This late in season I'd use Immunox and Captan. Immunox is effective against black rot and boIt looks like it could be black rot. This has been a very humid year. I have a little spotting on my grapes, which is just about unavoidable here. Might want to mix in Serenade as well to beef up the fungal resistance.
 
Had slight mildew last year and sprayed with bordeax mix in spring.

Many organic fungicides work best using a schedule of spraying every 7 to 10 days, from early spring, till your grape berries enter veraison (i.e. maturity often easiest seen as color change in red grapes).

Yes, you can spray less with organic sprays. As some years, that may be very hot and dry, will need less spraying. But another year that is just a little bit more cool and moist can result in lost crops if not sprayed enough. To know how to optimally spray is complicated, and to get best results, spaying on a simple schedule is most effective.

Also strange white an pink long growths from trunk about 4 ft up. View attachment 76700

I suspect those are simply areal roots.

https://blog-fruit-vegetable-ipm.ex...4/creepy-but-harmless-grape-aerial-roots.html
If those appear, you probably have a lot of humidity this year, which is why your grapes are also showing fungus due to not spraying enough, or your vines may be stressed (too much heat, water stress, disease stress, etc.).

Hope this helps.
 

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