Recent advances in food safety research are enabling plant pathologists to gain insight into how dangerous human pathogens, such as strains of E. coli and Salmonella, can survive on fresh fruits and vegetables and what can be done to control future outbreaks.

According to Steve Scheuerell, faculty research associate at Oregon State University’s Department of Botany and Plant Pathology, there has been an increase in reported human disease outbreaks associated with fresh produce over the last couple decades. "When an outbreak occurs, most of the infected produce has already been consumed," said Scheuerell. "Usually recalls won’t help. This is why prevention is key to keeping food safe," he said.

To reduce the potential for the transfer of pathogens to fresh produce, plant pathologists are stressing the need to implement and maintain sanitary growing and harvesting conditions worldwide. "As the U.S. increases its importation of produce, it is increasingly important to us that growers everywhere have good quality irrigation water and sanitary conditions for their workers," Scheuerell said.

"On the domestic front, the National Organic Program has taken the lead in implementing proactive measures to prevent potential contamination of fresh produce with human pathogens," Scheuerell said. Examples include mandated pre-harvest intervals for the application of manure and proposed quality assurance testing regulations
for compost tea regulations (a brew of compost with water used as a biocontrol agent or fertilizer). "Using techniques developed by plant pathologists, scientists are just beginning to understand how human pathogens colonize leaf surfaces, and how their survival can be influenced by manipulating leaf surface microflora and environmental conditions," he said.

Plant pathologists from across the country will present more on this topic during the Food Safety as Influenced by Phyllosphere Microflora symposium at the APS Annual Meeting in Anaheim, Calif., July 31 - August 4, 2004. The food safety symposium will be held Tuesday, August 3, 2004 from 9 a.m. to 12 p.m. at the Anaheim Convention Center, Anaheim, Calif. Members of the media are invited to attend annual meeting events; complimentary registration is available.

The American Phytopathological Society (APS) is a non-profit, professional scientific organization dedicated to the study and management of plant diseases, with 5,000 members worldwide.