In certain areas across the state of California, specifically in the San Joaquin Delta, Central Valley and coastal counties, wine grape growers are reporting that their grapevines are mysteriously collapsing. Fortunately, a team of growers, pest control experts and scientists, and the Lodi Winegrape Commission, have studied these dying vines and have determined that viruses are likely involved in what is called “sudden vine collapse”.

The research has shown that the combination of a leafroll virus and a vitivirus may be the cause of this mysterious disease. Once an infected vine is dead, the virus-carrying mealybugs move to a live vine to obtain a new source of food which potentially spreads the virus contributing to the collapse.

How to Manage Sudden Vine Collapse

• Test your vineyard – If you think your vines could be infected, you can test both your healthy and collapsing vines for Leafroll virus (1, 2, 2RG and 3) as well as Grapevine virus A, B, D and F (GVA, GVB, GVD, and GVF).
• Remove the infected vines – As of now there is no cure for grapevine viruses, so the most efficient way to reduce the spread of the viruses is to remove the infected vines from the field. The USDA Tree Assistance Program is providing financial assistance to eligible growers who need to remove a vineyard infected with leafroll virus.
• Reduce the mealybug vectors – Grow West can help you manage vine mealybugs. This will help you protect your healthy vines and the vines of your neighbors.

To learn more about virus management, visit www.lodigrowers.com/growereducation/viruses. Contact Grow West today to learn how we can help you manage your vineyard.