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Disease risks from this weekend

It looks like we are going to have another wet week...

The rain on the 29th was a very short one, but it was enough to make leaves wet for about 10 hours and the average temperature was higher 60F.  It was infection event for downy, black rot, and Phomopsis.  The rain on the 30th was too short for any infection.

Once again, the current condition favors development of downy mildew and black rot.  Please do not let something like the picture below happen to you!  (Downy mildew on a cluster, taken from our downy mildew trial.)


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Comments

  1. Vitor GuimaraisJuly 1, 2013 at 11:06 PM

    Hi Mizuho,

    Hope everything is good with you.
    I don't know what to do... I've sprayed last June 25th and since then I had 1.1" accumulated rain with all this humidity and heat.
    I think we will not be able to spray until Friday the 5th of July because there's a forecast of rain Tue, Wed and Thur...
    Last spray I used Prophyt, Sulfur and Scala. I'm thinking about using Prophyt + Captan, Sulfur and Pristine (some berries are touching and bunches closing) next spray.
    What should I do?

    Thanks,
    Vitor

    ReplyDelete
  2. Mizuho NitaJuly 2, 2013 at 8:39 AM

    Hi Vitor, I think you have a good program. Do you see any diseases in your vineyard?

    ReplyDelete
  3. Vitor GuimaraisJuly 2, 2013 at 10:53 PM

    Not really but with all this rain, humidity and heat you never know! We will try to spray tomorrow (Wednesday) and see what happens!

    thank you!

    ReplyDelete

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