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Potato Sprout Inhibitor Discovered at WSU Now Approved for Commercial Use

PULLMAN, Wash. – Consumers will soon be able to leave potatoes on the shelf a good deal longer, with federal regulators approving a natural food additive that will keep tubers from sprouting.

American Vanguard Corporation (NYSE:AVD) announced that its wholly owned subsidiary, AMVAC Chemical Corporation (AMVAC), has received registration from the Environmental Protection Agency for SmartBlock®, a novel potato sprout inhibitor. Canadian and European registrations have been filed and these approvals are progressing on schedule.

SmartBlock features a patented new class of potato sprout inhibitor technology that represents a breakthrough approach in the treatment of post-harvest potatoes. The product is a naturally occurring molecule, an FDA-approved direct food additive and is classified by the EPA as a biopesticide. It offers safe, comprehensive long-term storage control and requires no capital investment by customers since it is easily applied using existing equipment. AMVAC will begin marketing SmartBlock in the United States immediately.

The technology was discovered at Washington State University by Rick Knowles, scientist and chair of the Department of Horticulture, and Lisa Knowles, assistant research professor of horticulture.

The technology involves the application of naturally occurring organic compounds after potatoes are harvested and at the onset of sprouting. In testing, the WSU research team found that one application inhibits sprouting from two to three months. Two to three applications can provide full season sprout suppression. Applications leave little residue.

About half of the 9.4 billion pounds of potatoes grown in Washington each year are stored to provide a continuing supply to fresh markets and processing plants. Most varieties begin to sprout three to four months after harvest. Sprouting hastens deterioration and reduces overall quality. Growers and processors in the Pacific Northwest, which account for more than half the total potato acres in the U.S., spend an estimated $7 million to $9 million annually to inhibit sprouting of stored potatoes, according to Knowles.

The new technology provides an alternative for other compounds currently used to inhibit sprouting and will facilitate expansion of fresh and processed product exports, particularly to markets with strict chemical residue limits.

The Washington potato industry has a $4.6 billion economic impact and contributes more than 23,000 jobs to the state of Washington, according to the Washington State Potato Commission.

Anson Fatland, director of WSU’s Intellectual Property office said, “We are very pleased to have partnered with AMVAC on the SmartBlock technology. As a result of this very productive and collaborative research relationship, additional intellectual property was developed which resulted in worldwide patent protection.”

Dan Bernardo, WSU’s vice president for agriculture and extension and dean of the College of Agricultural, Human, and Natural Resource Sciences (CAHNRS), said, “Drs. Rick and Lisa Knowles have been at the forefront of postharvest research of potatoes and this success exemplifies the high quality research being carried out by CAHNRS faculty that has significant impact on Washington potatoes.”


Media Contacts

Rick Knowles, scientist and chair, 509-335-3451
Lisa Knowles, assistant research professor, 509-335-1874