Michigan Grape Facts: Managing Grapevine Leafroll DiseaseDOWNLOAD FILE
April 27, 2020 - Author: Laura Miles, Jan Byrne, Jerri Gillett, Mark Longstroth, Rufus Isaacs and Timothy Miles
Grapevine leafroll disease is a major viticultural problem that can be found in every wine, juice and table grape-growing region in the world. Unfortunately, Michigan is no exception. There are several different viruses associated with this disease, all belonging to the same virus family, Closteroviridae. There is great diversity within this family; together they are all known as grapevine leafroll-associated viruses (GLRaV) and each discovered virus has been named with a consecutive number.
Vineyard surveys conducted in Michigan during 2010 and 2016 revealed the presence of viruses that cause grapevine leafroll disease. GLRaV-3 was most common, followed by GLRaV-2. This matches the pattern seen in other grape production regions, where GLRaV-3 is the most widespread grapevine virus. Although sources of grapevine leafroll disease resistance have not yet been identified, growers can make use of the management strategies presented here to reduce the impact of grapevine leafroll disease in their vineyards.