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Disease risks from 6/6-6/8 rains

A series of rain event started around 9:30 AM on June 6th, and continued on until about 2AM on June 8th at Winchester.  Thus we had a wetness event for about 40 hours with an average temperature of lower 60F (~63F).  It was long and warm enough for Phomopsis, black rot, downy mildew, and Botrytis. 

If you are planning for fungicide application to reduce the risk of on-going infection of downy mildew or black rot, please refer to this post, or PMG, or my workbook (PMG and workbook are listed under "Resources").  Looks like chances of rain remain high for next few days across the state.

FYI: Because we have seen downy mildew in our vineyard since last week, we applied Prophyt (a phoshite material) and Ranman (cyazofamid) yesterday morning.  A phosphite material and cyazofamid has a kick-back activity and a protective activity against downy mildew, respectively.  (Note: We did not apply a material for black rot, because it may interfere with some of our experiments.) 
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