Why the World's Most Popular Wine Grapes Are Vulnerable to a Pandemic

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When you're in the wine shop looking for the right wine to pair with your meal or bring to the party, the variety on the shelves seems rich and diverse, their taste influenced by the grape, soil, climate, and age. Among the most famous are the French "noble wines"—cabernet sauvignon, merlot, pinot noir, chardonnay, riesling, and sauvignon blanc—so called for being associated with high quality and easy growth in a variety of places.

But it turns out that many of the most famous grapes in the world are like nobility in another way: They're as inbred as a royal family, and have been for hundreds—and in some cases thousands—of years.

"Scientists are getting really concerned that this is setting up the perfect scenario for a great pandemic," Kevin Begos, whose new book, Tasting the Past, explores the history, archaeology, genetics, and future of wine, said at a recent book release event in New York City. They fear that a single merciless pathogen could wipe out many grapes around the world in the same way that a single fungus, Phytophthora infestans, eradicated the variety of potato common across Ireland in the 1840s, causing the great famine.

The vast majority of wine produced across the world derives from a single grapevine species: Vitis venifera. The domesticated grape has thousands of varieties, and quite a lot of genetic diversity among them, according to a 2010 paper in PNAS that analyzed genome-wide genetic variation of more than 1000 samples of V. vinifera subsp. vinifera and its wild relative, V. vinifera subsp. sylvestris. But that's not true for all grapes: Nearly 75 percent of cultivars had a first-degree relationship to at least one other. They were either parents or children.

The most popular commercial wines are made from a handful of these inbred grapes. Sauvignon blanc, for instance, has a first-degree relationship with cabernet sauvignon, cabernet franc, and chenin blanc, among many others. That genetically cozy family isn't unusual. You see it all over the grapevine.

Another problem is how grapes reproduce in vineyards. Instead of pollinating these hermaphroditic plants or growing them from seeds, as might happen naturally, grape growers generally make new plants from cuttings of existing ones, essentially cloning the same vines over and over.

They use this method to produce consistent flavor quality—and it's nice to decant a bottle of your favorite wine and know what to expect with the first sip. But this practice has kept some popular grapes in relative genetic stasis for a long time. Take pinot, parent of chardonnay and gamay, which has been cloned for 2000 years. Genetically, it's remained virtually unchanged—but the organisms that prey on it have not. "All those insects and pathogens and mildews that attack grape vines have been evolving," Begos said. "And they always figure out new ways to attack the grape vines."

Despite the wide use of pesticides—in the last 10 years, 260 million pounds of pesticides were put on wine grapes in California alone—"the industry is losing the arms race to the pathogens," Sean Myles, an author of the 2010 PNAS grape genome study, told Begos in Tasting the Past. "It’s really only a matter of time. If we just keep using the same genetic material, we’re doomed.”

The good news is that grape diversity could be the key to preventing rosé season from disappearing. Scientists are looking outside the noble wines and their popular cousins to old, wild, and lesser-known varieties, which "turn out to have natural disease resistance, and they've kept evolving," Begos said.

The idea is create hybrids selected for specific traits—not just pest resistance, but an ability to withstand greater heat in an era of climate change, adaptability to a wider variety of soils, and other resilient qualities.

One effort is VitisGen, a USDA-funded project involving researchers from a handful of American universities, including UC Davis, Cornell University, and the University of Minnesota. By studying the genomes of a variety of grapes, they're creating an enormous database of genetic traits. They're also experimenting with crossbreeding. Some of this genetic tweaking is decidedly old school, including pollinating grapes by hand.

Begos tells Mental Floss that they're especially interested in developing grapes that are resistant to downy mildew (Plasmopara viticola), a potential plague a la the potato famine. It can cause total crop loss if not controlled.

When it comes to selecting traits, it probably won't be flavor they'll be pulling from wild grapes, which "are really kind of terrible," Begos said. (In Tasting the Past, he quotes wine experts who describe the flavor of a fox grape as combining "animal fur and candied fruits.”) It's generally hardiness they're looking for. The concord grape in your kid's PB&J, for example, is "really tough," Begos said. Select some of its hardy genes and cross them with, say, the peppery flavor genes of the syrah grape—which the researchers have also identified—and maybe you can create a genetically resilient hybrid.

"The University of Minnesota has already had success identifying cold-hardy wine grape genes, and breeding them into new varieties that have impressed the toughest critics," Begos says, pointing to a 2015 top 10 wine list from New York Times food critic Eric Asimov. Number two on the list was made from hybrid grapes developed by UM.

You can do your part to encourage wine diversity by getting adventurous with your vino, trying a grape you've never heard of or blends from new regions. Check out organic and small wineries, which are experimenting with old cultivars and new varieties. And don't be afraid of a future with genetically tweaked grapes. We've been modifying them as long as we've been growing them. As Begos writes of these efforts, "At heart they’re unlocking flavor, disease-resistance, and growth genes that may be tens of millions of years old. To me these scientists are doing exactly what ancient Babylonians, Egyptians, and Greeks did: refining wine grapes to produce tastes we enjoy."

Archaeologists Uncover World's Oldest Known Brewery in Israel

People have been knocking back beers for 13,000 years, according to new archaeological findings out of the Middle East. As Science magazine reports, evidence of wheat and barley-based beer was found inside stone mortars carved into the floor of a cave near Haifa, Israel.

The Raqefet Cave was used as a burial site by the Natufians, a group of semi-nomadic hunter-gatherers who were also responsible for the world’s oldest known bread, which was discovered in Jordan in July. These findings challenge previous evidence that traced the origin of beer back just 5000 years.

Beer was also previously believed to be merely a by-product of bread-making, but archaeologists say that isn’t necessarily the case. Instead, researchers believe beer may been served during ritual feasts “to venerate the dead and/or to enhance group cohesion among the living,” researchers wrote in their paper, published in the Journal of Archaeological Science: Reports.

Remarkably, the Stanford University researchers who made this discovery weren't even looking for evidence of alcohol. “We did not set out to find alcohol in the stone mortars, but just wanted to investigate what plant foods people may have consumed because very little data was available in the archaeological record,” Li Liu, a professor of Chinese archaeology at Stanford, said in a statement.

Researchers theorize that beer brewing may have inspired the Natufians to cultivate cereals in the region, but it’s not currently known whether beer or bread came first. The mortars dug into the cave floor were reportedly used for storing and pounding wheat and barley, as well as brewing beer.

The beverage wasn’t exactly what we know as beer today, though. According to the BBC, the prehistoric beer was “gruel-like” and similar to porridge. It was likely weaker than modern beer, too.

[h/t Science]

Newly Uncovered Galileo Letter Details How He Tried to Avoid the Inquisition

Galileo Before The Papal Tribunal by Robert Henry. Hulton Archive, Getty Images
Galileo Before The Papal Tribunal by Robert Henry. Hulton Archive, Getty Images

Galileo Galilei was one of the Roman Catholic Inquisition’s most famous targets. As a result of his outspoken support for the theory that all the planets, Earth included, revolve around the Sun, the Catholic Church charged him with heresy and he spent the last years of his life under house arrest. Galileo was well aware that he was on the Church’s hit list, and a newly discovered letter shows that at one point, he tried to tone down his ideas to avoid persecution, according to Nature and Ars Technica.

The letter in question, written in 1613, solves a long-held mystery for Galileo scholars. It was found in the library of the Royal Society, where it has been for at least 250 years.

Galileo’s beef with the Catholic Church came about because of his support for heliocentrism—the idea that the solar system centers around the Sun—as advocated in Nicolaus Copernicus’s book De Revolutionibus. Galileo’s scientific writings clearly endorsed Copernicus’s theory of the world, including in personal correspondence that was widely disseminated, and in some cases, he directly questioned the scientific merit of Biblical passages.

In 1613, Galileo wrote to a friend and former student named Benedetto Castelli who was then teaching mathematics at the University of Pisa. The letter was a long treatise on Galileo’s thoughts on Copernicus’s ideas and religion, arguing that science and astronomy should not be overpowered by religious doctrin . (He would later expand this into his Letter to the Grand Duchess Christina.) As with many of Galileo’s writings at the time, the letter was copied and disseminated widely, and eventually, a friar named Niccolò Lorini forwarded it to the Inquisition in Rome in 1615.

This is where things get tricky. Galileo claimed that the version of the letter Lorini sent was doctored to be more inflammatory. He sent a less controversial version of the letter to a friend, saying that it was the original document and should be forwarded to the Vatican, essentially to clear his name. But scholars have never been able to be totally sure if he was telling the truth about the letter being doctored.

This newly discovered letter suggests that he was lying, and that he himself was looking to tone down his rhetoric to appease the Catholic Church and keep authorities from quashing the spread of heliocentric ideas. The original copy found in the Royal Society archives shows changes to the wording in what appears to be Galileo’s handwriting. The seven-page letter, signed “G.G.,” includes changes like swapping the word “false” for the more slippery “look different from the truth,” changing “concealing” to “veiling,” and other edits that seek to tone down the rhetoric that inflamed Church leaders. The wording and handwriting corresponds to similar writing by Galileo at the time. Based on this finding, it seems that Galileo did seek to make his ideas more palatable to the Catholic Church in the hopes of escaping persecution by the Inquisition.

Discovered on a research trip by science historian Salvatore Ricciardo of Italy's University of Bergamo, the letter may have been overlooked in the Royal Society archives because it was cataloged as being dated October 21, 1613 rather than the date it actually bears, December 21, 1613. However, it’s unclear how it came to the Royal Society in the first place. The document is the subject of a forthcoming article by Ricciardo and his colleagues in the Royal Society journal Notes and Records, according to Nature.

The minor changes Galileo made did not successfully hold off the Church’s crackdown on heliocentrism. In 1616, the Inquisition ordered Galileo to stop teaching or defending the theory, and several of his books were subsequently banned. He would stand trial again almost two decades later, in 1633, on suspicion of holding heretical thoughts. He was found guilty and sentenced to house arrest, where he remained until his death in 1642.

[h/t Ars Technica]

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