We asked Andy Walker, a geneticist, professor, and Louis P. Martini–endowed chair in viticulture in the Department of Viticulture and Enology in the School of Agricultural and Environmental Sciences at the University of California, Davis, about the future of California’s wine.
Boom: What is the legacy of the California Mission grape and its role in our state’s wine legacy?
Andy Walker: The Mission grape variety was brought into California in the mid-1760s by Spanish missionaries as they explored California and established the missions. We thought for many years that this grape originated from a collection of seeds from an unknown variety in Spain that Spaniards brought to the New World in the 1560s. Recent DNA-based testing has found that Mission is the same as Listan Prieto, a grape from the Canary Islands—the last stop to load food and water on the way to the edge of the earth or the Americas, whichever came first. They also brought Muscat of Alexandria. Interestingly, the Torrontes grape of Argentina and several obscure relatives turn out to be hybrids of Listan Prieto (Mission) and Muscat of Alexandria, and may have been crossed and created here in the New World. Mission was widely grown until the Gold Rush era when Europeans brought better quality wine grapes to meet the expanding wine demand in the state. It is a very vigorous variety with very high yields and well suited to dry arid conditions with limited rainfall, but it has poor color and is often astringent.
Boom: How are California grape growers and vinters investing in sustainable practices?
Walker: Sustainability has become a key concern for the California wine industry and has focused on soil, water, energy, and labor. Water will be one of the biggest challenges to viticulture in our dry and overpopulated state. Growers are rethinking their irrigation and rootstock choices and considering a time in the near future in which water will be much more limited—perhaps due to the environment but certainly due to political, social, and environmental pressures.
Boom: How is the millennial generation of Americans—those in their twenties and thirties—driving new trends in wine consumption?
Walker: The most dramatic example is the sudden explosion of interest in Muscat wines (apparently the result of a few rap songs)—the acreage of these varieties has dramatically expanded in the last few years.
Boom: What are the possibilities on the horizon for out-of-the-box technological or genomic innovations that will challenge our perceptions of the limits of terroir, climate, and grape varietals?
Walker: One of the limitations in wine research has been the inability of machines to equal the human nose. We are now approaching that ability—and at the same time are in the midst of a genetic revolution due to the dramatic reductions in the cost of and improvements in approaches to genome sequencing. The next step will be to use these tools to understand the role of terroir in quality, or manipulate ripening profiles to combat climate change. I hope we see a movement toward using wine varieties that are better suited for warm climates and a greater willingness to use new varieties bred to be resistant to pest and diseases. Both of these fit the sustainability bill.
Boom: How do you see climate change affecting the California wine industry?
Walker: A changing climate will likely impact the varieties we choose to grow in a given region. It will also change the way we trellis and cultivate vines. I think we have the ability to produce excellent wines in a warmer climate.
Boom: What wines will we be drinking in 2050?
Walker: I think we will be using varieties with mildew resistance. Classical breeding is poised to take advantage of genetic markers for disease resistance and solve many grape disease problems. Foremost among these in California is powdery mildew for which growers apply fungicides prophylactically eight to twelve times (or more) per season. I also hope we are using some of the outstanding Sicilian and Spanish varieties that are well suited for California’s warm and dry climate.
Boom: What would you include in a time capsule for 2050?
Walker: The California Grape Acreage Report for 2012, an iPad mini, and as many of the endangered wild grape species as we could fit! These species are threatened across the United States by urbanization, agriculture, wanton disregard, and herbicide use by highway crews.
Image at top courtesy of Lee Coursey.