Could your favorite variety of wine one day disappear? If the traditional types of wine grapes grown for centuries in European vineyards go extinct, the sources of popular varieties of wine like champagne and bordeaux will run permanently dry.
And according to the results of a study on wine grape genetics recently published by scientists from Cornell University, extinction may be a real possibility for some types of wine grape in the future.
The study, led by Sean Myles of Cornell’s Institute for Genomic Diversity, sequenced the genomes of major wine grape varieties and discovered that, despite their distinct differences in color and flavor, all wine grapes of European origin are very closely related from a genetic point of view.
According to the study, wine grapes were domesticated about 8,000 years ago and moved to Europe about 5,000 years ago. But over all those thousands of years that wine grapes have been cultivated by humans, grape farmers have apparently stuck with a small set of favorite varieties that have rarely been crossbred. More recently, to increase yields and combat pests, farmers have taken to grafting new grape vines from old stock, rather than growing new plants from seed.
As a result, many of the grape varieties grown today are essentially genetic siblings to those grown a thousand years ago, and some vineyard fields are filled entirely with clones of a single plant. And from the grape plant’s perspective, that’s a problem.
The Importance of Genetic Diversity
In nature, most wild plants are constantly crossbreeding with other members of their species, creating a diverse population with a wide variety of individual plants that have differing genetic weaknesses and strengths. As a result of genetic diversity, when a wild plant species faces a new threat, such as a virus, a fungus or a new invasive pest, some individual plants are likely to have resistant traits that will help them survive — and then pass that resistance on to the next generation.
But the most common varieties of domesticated wine grapes are essentially inbred. There is little variation between varieties, and agricultural practices have actually prevented the plants from evolving pest resistance over time.
As a result, wine grapes have become more and more susceptible to fungi, viruses and insects, so conventional grape farming has become increasingly dependent on the use of chemical pesticides and fungicides. In the United States, 70% of all the chemical fungicides used in agriculture are used to protect grapes from the diseases to which they have so little natural resistance.
Beyond its negative consequences for the environment and the health of the workers who tend and pick conventionally grown grapes, this sort chemical warfare is only a temporary fix. New diseases and pests are continually challenging grape growers. In fact, the wine industry has already survived one near-death experience that could only be averted with the help of nature.
Wine’s Historic Brush with Extinction
In the 19th century, the Great French Wine Blight destroyed most of the wine plants in France, including those in the storied vineyards of the famous Champagne region, and dramatically decreased wine production across nearly all of Europe. The cause of this devastating plague was a tiny, sap-sucking insect called phylloxera, a native of North America that had been brought to Europe accidentally in shipments of wild North American grapes.
While wild American grapes have evolved a resistance to phylloxera, Eurpoean grapes had no defenses. In fact, the only way wine producers in Europe eventually saved their vineyards was to graft their traditional wine grape varieties onto American grape rootstock, a practice which continues to this day.
The Next Evolution of Wine
To protect wine grapes for future generations, wine lovers might soon have to develop a taste for new varieties of wine.
With the help of the grape genome sequencing research recently completed by Cornell’s scientists, botanists and agricultural experts can develop new grape varieties that are resistant to pest and disease by breeding domesticated grape varieties with wild grapes and one another to promote desirable results.
But will wine drinkers make a place in the cellar for these newcomers alongside bottles brewed from their more traditional ancestors?
Photo by FlagSteward, from Wikimedia Commons. Used under Creative Commons license.