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Media Contact: Glenn Brank
July 9, 2007(07-10)

Field Study Could Bring Sweet Smell of Success Back for Garlic Growers

SACRAMENTO – The Department of Pesticide Regulation will fund research that could provide California’s onion and garlic industry with a natural fungus fighter.

"This project offers a unique example of how our environmental and economic interests complement each other," said DPR Director Mary-Ann Warmerdam. "While modest in scale, this research points the way toward effective pest management without the use of fumigants."

If successful, the $40,000 project could be a major boost for growers who cultivate more than 50,000 acres of garlic and onions worth more than $300 million (plus significant revenue from processed products) a year.

California’s garlic and onion industry is threatened by "white rot," a rapidly spreading, persistent soil fungus that destroys the bulbs. White rot, which can lie dormant in the soil for up to 40 years, already has disrupted production on more than 13,000 acres of prime farm land in the San Joaquin Valley counties of Kern, Kings and Fresno.

In the Santa Clara-Gilroy area - known as the "Garlic Capital of the World" - less than 500 acres remain under cultivation due to white rot.

Soil fumigants such as methyl bromide and metam-sodium destroy most "white rot" but cannot eradicate it, and the cost of fumigation has become economically impractical for many growers, who face pressure from foreign competitors.

Under DPR’s two-year grant, the California Garlic and Onion Research Advisory Board and the University of California Cooperative Extension will commercially field test a naturally based compound found in onions and garlic. The compound "tricks" white rot into germinating, but in the absence of a crop, the fungus dies from starvation or is severely weakened.

Robert Ehn, technical manager for the onion and garlic board, said there appear to be no side effects from the treatment, other than the garlicky smell. "As white rot spreads, more and more acreage is being forced out of production," said Ehn. "This project is of critical importance, given the pressures on our industry."

Earlier this year, DPR proposed new regulations that would cap overall fumigant use in the San Joaquin Valley to reduce air emissions and meet state air goals. However, fumigant use has already declined in the onion and garlic fields due to falling commodity prices.

According to industry sources, more garlic is now imported from China than produced in California. Chinese production skyrocketed from about 50,000 pounds to nearly 3 million pounds in the last decade.

Industry contacts:

Robert Ehn, Technical Manager
California Garlic and Onion Research Advisory Board
(559) 297 - 9322

photo of healthy garlic bulb next to shriveled bulb infected with white rot.
A healthy young garlic bulb next to a shriveled bulb infected with white rot. (Photo courtesy Shannon Mueller, U. C. Cooperative Extension, Fresno.)

One of six departments and boards within the California Environmental Protection Agency, DPR regulates the sale and use of pesticides to protect people and the environment.