SAN FRANCISCO — Advancements have been made in the fight against the vine-killing disease threatening California’s $33 billion wine industry, including the development of grapevines genetically engineered to be resistant to it.
But consumers wary of genetically modified foods may not have to worry about their wine, since the new plants could have a hard time finding their way into vineyards.
While many conventional growers appreciate the research, they’re not likely to switch their vines over to the new ones resistant to Pierce’s disease if they become available.
Most growers are interested in learning more about the genetically engineered vines, but they haven’t yet expressed a desire to plant them, said Karen Ross, director of the California Association of Winegrape Growers.
“Most growers and most of the people in the industry support doing genomic research because we believe it’s an important diagnostic tool to better understand the problems we’re facing,” she said.
In an industry where old vines are prized, the new ones could have a hard time breaking into existing vineyards. New plants take four to five years before they bear fruit worthy of winemaking. And once the vines are producing, the wines take another two to three years to make, said Kari Birdseye, director of communications for the San Francisco-based Wine Institute.
“Because we’re such a traditional industry to begin with and because wines take so long to make, it takes longer for us to implement new sciences like this,” she said.
It also would be costly to plant the new vines.
“You usually try to get 25 to 30 years at least out of a vineyard,” said Mora Cronin, vice president of public relations for Beringer Vineyards in Saint Helena. “You don’t replant on a whim.”
Beringer has more than 10,000 acres of vines in California, and about 8,000 acres in Australia.
Pierce’s disease is caused by bacteria, carried through California predominantly by the glassy-winged sharpshooter. It clogs the water vessels in the vines, causing them to die. There is no cure.
California alone has spent about $10 million on research and about $40 million on efforts to combat the sharpshooter and the disease in the last two years.
The new vines were developed by University of Florida researchers who patented the genes in May. The scientists still are doing research on the genes, and Dennis Gray, a professor of developmental biology at the University of Florida Mid-Florida Research and Education Center, said it could be almost a decade before the vines are ready to be sold to growers.
If they ever are, growers will have to decide if it’s worth the expense to switch their vineyards over.
“We want people to enjoy our wines,” Birdseye said. “If people aren’t going to buy our wines because of what we’re doing with our vines, that’s going to defeat the purpose.’
Jay Van Rein, a spokesman with the California Department of Food and Agriculture, also emphasized the research portion of the scientists’ work, and not the production of an altered vine.
“I think the growers would question whether they would be able to sell that product,” he said.
The European Union has banned biotech foods, effectively eliminating that market from California vintners if they decided to use genetically engineered vines. Exports of U.S. wine, 96 percent of which came from California, grew 2 percent in 2000 to $560 million.
And certified organic wine growers can’t use genetically modified plants if they hope to keep their certification.
“I find it very difficult to believe that we would rely on a genetically engineered plant,” said Ted Hall, owner of Long Meadow Ranch, a certified organic winery. “It seems to me there are many other approaches to maintaining balance in the environment than fundamentally altering the structure of a plant beyond what you could achieve with breeding and hybridization.”
The damage to vineyards in California by Pierce’s disease hasn’t been measured very accurately, Van Rein said. It has mostly affected Southern California vines.
Efforts to combat Pierce’s disease include inspecting shipments of nursery plants or agricultural commodities for the glassy-winged sharpshooter, Van Rein said.
The state also is using a wasp that lays its eggs in the sharpshooter’s eggs to keep the bug under control.
California wine accounts for the bulk of the wine consumed in the United States, with roughly three out of every four bottles sold in the country coming from the state. If California were a nation, it would be the fourth-leading wine-producing country in the world, according to Wine Institute statistics.