ORGANIC APPLE AND GRAPE PERFORMANCE IN THE MIDWESTERN U.S.

Since 1999, there has been a resurgence of interest in grape and organic fruit production in the Midwestern U.S. state of Iowa. With the new U.S. federal rules governing organic production becoming effective in October 2002, any products sold as “organic” in the U.S. must be grown without synthetic fertilizers, pesticides, genetically modified seeds or ingredients, antibiotics or hormones for a period of 3 years, but “wine made with organic grapes” may contain 100 ppm sulfur dioxide. In an Organic Grape Vineyard Survey, conducted in 2002, and at the Organic Grape Vineyard Demonstration, viticulturists reported planting Vitis labrusca or V. labrusca hybrids with inherent disease-tolerance as their most important method for managing diseases. Integrated weed management, using cover crops, mulching and mowing, offered the option for weed control. Successful organic apple production relies on insect mating disruption and integrated pest management, including apple scab disease-resistant cultivars and non-synthetic pesticides, such as kaolin clay particle film. Research conducted in a certified organic apple (MalusHdomestica Borkh.) orchard in 2000 determined that kaolin particle film was effective in lowering codling moth and plum curculio insect damage in Redfree and Jonafree apples during the growing season and in Jonafree apples at harvest. Beneficial insects were not harmed by the kaolin clay treatments. Apple productivity and yields were not affected by pest management treatments. In postharvest examinations, washing significantly reduced yeast and mold populations on kaolin particle film-treated apples. Organic fruit production will become a viable niche market in the Mid¬western U.S. as producer and consumer demand for less pesticides in the environ¬ment increases and pest management technology is advanced through cooperative efforts between universities and private industry.