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Hot weather and powdery mildew

As you know, we are expecting to have a high temperature for next few days.  Please protect yourself from heat related illnesses.  

Having this much of heat is not really a fun, but there is a good aspect as well.  Powdery mildew pathogen cannot survive very well under high temperature.  At 33C (92F) or more, this fungus will suffer, and colonies can get killed.  If there is an extensive exposure to the sunlight and high temperature (as we have right now), they will have a difficulty surviving.  A study has shown that the fungus colonies will be completely killed after 12 hours at 35C.  Thus, this heat wave should reduce the risk of disease development, especially if you had a good canopy management.
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Comments

  1. C VroomanJuly 7, 2010 at 6:54 AM

    Ahh.. A silver lining to these red-hot days. Thank you, Mizuho.

    ReplyDelete
  2. Mizuho NitaJuly 26, 2010 at 10:03 AM

    Hi Christie,
    Yes, indeed. I hope you don't have much powdery at your place.

    ReplyDelete

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