Page 49 - Grapevine May-June 2020

Around The Vineyard

Powdery Mildew Management Plan
for 2020

Pscheidt recommends the following steps for
managing powdery mildew during the upcoming
2020 season:

• Review the overall 2019 plan devised for man-
aging powdery mildew to assess its suc-cess, as
well as the areas needing improvement.
• Devise a fungicide program based on the histor-
ical use of those products in this particular vine-
yard. Assess those products that were proven to
be the most effective.
• Engage in timely vineyard management in terms
of canopy, system, leaf pulling and sucker con-
trol.
• Do hotspot monitoring. Focus on the vigorous
areas of the vineyard, as that is where there’s
most likely to be problems with powdery mil-
dew. Monitor weather and vine growth, and
scout for disease in this area to ascertain exactly
where adjustments to the program are needed.
• Use short intervals during and shortly after
bloom by using the best products at the be-gin-
ning of the season. Do not wait to use the best
products until later after powdery mil-dew has
begun to form.
• Adjust intervals of application of products to hit
10% bloom.
• Sulfur and alternative products should have
multiple applications during bloom.

Those looking for additional information about
wine grape production with a focus on Oregon
can log on to https://extension.oregonstate.
edu/crop-production/wine-grapes. For the latest
re-search on resistance in powdery mildew, check
out this the resources offered via the Fungicide
Resistance Assessment, Mitigation and Extension
Network (FRAME) at https://framenetworks.wsu.
edu

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