Managing grapevine leafroll disease

Laura Miles<lmiles@msu.edu>, Jan Byrne<byrnejm@msu.edu>, Jerri Gillett, Mark Longstroth, Rufus Isaacs<isaacsr@msu.edu> and Timothy Miles<milesti2@msu.edu>, Michigan State University - April 27, 2020

New grape fact sheet on grapevine leafroll disease management now available.

Symptoms of grapevine leafroll disease — Typical symptoms of grapevine leafroll disease in Pinot Noir (foreground) and Chardonnay (background) grapevines. Note the leaf curling and green coloration of main veins. Leaves turn red in the infected Pinot Noir vine whereas leaves appear chlorotic (yellowish) in the Chardonnay vine. Photos by Marc Fuchs, Cornell University.

In collaboration with the Michigan State University grape team and funding from Michigan State Horticultural Society and Michigan Craft Beverage Council, we are releasing a new Michigan Grape Facts resource for growers battling grapevine leafroll disease or simply wanting to keep informed. Michigan Grape Facts: Managing Grapevine Leafroll Disease is now available at the MSU Extension Grapes website.

Download Michigan Grape Facts: Managing Grapevine Leafroll Disease

Viruses associated with grapevine leafroll disease can be common issues in viticultural regions and Michigan is no exception. The extent of the impact that this disease can have varies depending on the circumstances in a particular vineyard block. Factors that include grape variety, viruses involved and environmental conditions drive the expression of disease symptoms. In general, the management of diseases caused by viruses starts with prevention; however, grape growers can make use of the management strategies laid out in the fact sheet to reduce the effects of grapevine leafroll disease.

Key messages

Avoid – Do not use budwood or cuttings of unknown health status.
Exclude – Plant virus-tested material from a reputable nursery.
Protect – Apply dormant sprays to control overwintering mealybugs and scale insects.
Eradicate – Remove all virus-infected vines.

This article was published by Michigan State University Extension. For more information, visit https://extension.msu.edu. To have a digest of information delivered straight to your email inbox, visit https://extension.msu.edu/newsletters. To contact an expert in your area, visit https://extension.msu.edu/experts, or call 888-MSUE4MI (888-678-3464).