USDA Collection Preserves Garlic's Genetic Diversity

USDA Blog Post:

Posted by Jan Suszkiw, USDA Agricultural Research Service Information Staff, on March 25, 2014 at 2:00 PM

“This group of diverse garlic germplasm represents all the types that might be found at a farmer’s market.” Photo courtesy of Barbara Hellier, ARS

This post is part of the Science Tuesday feature series on the USDA blog. Check back each week as we showcase stories and news from the USDA’s rich science and research portfolio.

Raw or dehydrated, garlic is a staple ingredient in dishes the world over. This herb, Allium sativum, is also the focus of medical research investigating the health-imparting properties of allicin, a compound that gives garlic its pungent aroma and flavor.

Americans consumed 2.3 pounds of garlic per person in 2010. Perhaps most familiar to consumers is the large white bulb commonly sold in supermarkets. But there’s more diversity there than meets the eye, or the taste buds, says USDA Agricultural Research Service (ARS) horticulturist Barbara Hellier.

It’s no exaggeration to say Hellier knows her garlic—and her leeks, chives, shallots, and wild onions, for that matter.

Hellier is curator of the National Plant Germplasm System’s Allium Collection at the ARS Western Regional Plant Introduction Station in Pullman, Wash. She oversees the maintenance, description, and distribution of 293 garlic specimens, 16 primitive garlics, 207 leeks, 44 chives, and 579 wild, ornamental and native Allium species.

“What we see in supermarkets is generally one type—a white softneck type and elephant garlic, which isn’t really garlic, but rather a type of leek,” Hellier says. Garlic lovers with a taste for something a bit more diverse might try a farmer’s market, for example, or place an order with a specialty grower. “At a farmer’s market, shoppers are likely to come across more of the true diversity of garlic, like the hardneck purple to purple-stripe types; small, pearly white silverskins; creole-type hardneck with red clove skin; or  white hardnecks with fiery hot taste.”

The Pullman collection includes garlic specimens acquired from around the world—but especially Central Asia, the crop’s point of origin—and serves as a backup to varieties grown commercially in the United States.

Today’s garlic is vegetatively propagated, meaning it’s grown from cloves, not seed. However, “There is no potential for breeding new varieties with vegetatively produced plants,” notes Hellier.  Recently, she and ARS colleague Phil Simon have been assisting small-scale growers seeking to reverse that trend using several of the collection’s seed-producing garlics.

“It will be interesting to watch what comes from the efforts of these growers trying to produce true seed,” she says. “They have passion for garlic and are looking for novel traits.”