Issue link: http://winesandvines.uberflip.com/i/70673
G r AP e G ro W in G that were more susceptible to common viruses. We called this the "latent virus" issue at the time and were able to prove that AXR-1 was a rootstock that was tol- erant of virus while many of our current favorites are much more susceptible. If a grower wants to use a field selec- tion, I always recommend planting a small block of the rootstock he is plan- ning on using with budwood from his selected source. This is a simple, empiri- cal test that can give you a lot of infor- mation. After a few years, you can see if there are any obvious problems. Screen- ing the selection by testing in a commer- cial laboratory for virus can be helpful, but it isn't a perfect solution: One set of tests at a particular time of year isn't really enough to know what viruses are there. The same type of virus—say, leafroll virus type 3—has both mild and severe strains. You can't predict which strains will be severe. Looking for a perfect match? Devoted grape grower seeks serious buyer Chip buds from newly imported vines are grafted to rooted St. George indicator root- stock and monitored for virus for two years. There is the age-old question of whether wine quality can be improved by virus infection. Fewer and fewer winemakers buy into this idea today, but there still are some. My colleagues and I have a large research vineyard that went in this year at the UC Davis plant pathol- ogy farm with multiple virus treatments against multiple rootstocks. In a few years, we'll be able to make experimental wines and let people make up their own minds. But given that the leafroll viruses and the vitiviruses cause reduced sugar and color in fruit, it is pretty hard to imagine this is a good thing. The most forward-thinking wineries ad- dress this issue by bringing their impor- tant field selections to FPS and having us test them thoroughly and provide disease- elimination therapy if they are virus- Wines & Vines FeBRUARY 2011 47 Object: Supply the wine grapes or bulk wine you need Likes: Working in my vineyard; enjoying great Sonoma County wine with family and friends We can help you find your ideal match — the right grower for your needs, from those perfect Chardonnay or other grapes to quality bulk wine. Who knows, it could lead to a rewarding long-term relationship. Get to know our grape growers at SonomaWineGrape.org. Need grapes? Find the grapes or bulk wine you want, in one central location, any- time, day or night at the Sonoma County Grape Marketplace: SonomaWineGrape.org/marketplace BRIDGET WILLIAMS