Virginia Grape Disease Updates

Here are slides from my presentations at UGA Seasonal Vineyard and Pest Management Conference. 1) Ripe rot research updates 2) Introduction to trunk disease diagnostic aid app and GrapeIPM.org. FYI: Our next grape disease management meetings are at Loudon County Extension Office. Please RSVP with Ms. Beth Sastre (flores69 (at mark) vt.edu). Thursday, April 04, 2019 Vineyard IPM Program (1 - 4 pm) Disease management in the Vineyard ( Spanish ) Loudoun County Cooperative Extension office 750 Miller Drive, SE Suite F-3 Leesburg, VA 20175 Friday, April 05, 2019 Vineyard IPM Program (1-4 pm) Disease Management in the Vineyard ( English ) Loudoun County Cooperative Extension office 750 Miller Drive, SE Suite F-3 Leesburg, VA 20175

Here's a 2019 version of fungicide application template. Please read the footnote for downloading onto your computer or copy to your Google Drive to use it. This template is designed to be used as a guide. You need to create your own plan based on your vineyard(s)!! If you have time tomorrow afternoon, please join us for our first grapeIPM.org training session , which will be held at Horton Vineyards from 1 PM. It would be a great excuse to visit Horton to taste their award-winning wines!

We will hold a training session for GrapeIPM.org on March 15th (this Friday) at Horton Vineyards  (6399 Spotswood Trail, Gordonsville, VA 22942). The meeting starts at 1 PM and closes at 3 PM. GrapeIPM.org is our new online database and risk assessment system which allows you to manage your pesticide records and planning. We introduced it to select growers in 2018, and we are extending the invitation to more growers this year. You can assign multiple vineyards or blocks (whichever you wish to call).  The system has a pre-made list of commonly used fungicides (we are working on insecticide now), thus, what you need to do is pick the one you have in your inventory, and enter in the system's calendar.  If you happen to use not-so-common pesticides, we are working on an interface that allows you to enter your own. You can enter the area to be applied and the size of your sprayer, and the system will give you an estimate of how much you need to mix in your spra...

At this time of the season, I am often asked about an application of fungicide(s) to dormant vines. I totally understand that you want to do something before things get busy. A dormant application of lime sulfur (10% in our study, or 1% of a newer product called Sulforix in a study done by Dr. Annemiek Schilder at Michigan State Univ.) should be effective against Phomopsis and/or Anthracnose . We also tested cupper, but it was not effective. However, the efficacy of the application is not strong enough to allow you to skip any preventative fungicide applications to be sprayed soon after bud break. (i.e., even with a dormant application, you still need to protect your shoots when they emerge.) With the corrosiveness of lime sulfur, I feel that it is not worse the money and time, plus, it will be another application of a fungicide, which we try to reduce. It is much effective to spray mancozeb or captan soon after bud break. Thus, I would recommend a dormant application ...

Captan, which we use extensively to manage downy mildew, Phomopsis, ripe rot, and other grape diseases, is currently under review by the EPA. In order to keep captan as one of our tools to control grape diseases,  please respond to the EPA's registration review page to post your comment  (will open the EPA page). With increasing cases of fungicide resistance with newer products in our region, it is very important for the majority of commercial grape growers located east of the Rockies to keep older multi-site materials such as captan to be used as a backbone of the spray program.  Also, please forward the message to other producers and stakeholders who should respond to the need for this fungicide in our industry.