Submitted to: International Symposium on Biological Control of Arthropods
Publication Type: Abstract Only
Publication Acceptance Date: November 26, 2004
Publication Date: N/A
Technical Abstract: Bacillus thuringiensis (Bt) maize has become increasingly popular with U.S. growers since it was commercially available in 1996. Yield protection, reduced need for insecticides, improved grain quality, and ease of use are benefits that motivated growers to plant 32 percent of total acres to Bt maize in 2004. Rapid adoption of a technology raises many questions concerning product longevity and how the technology will influence the corn agricultural ecosystem. Overuse could result in the development of resistant insects or economic populations of secondary pests, or influence populations of non-target insects. Studies are ongoing to determine possible impacts, positive and negative, that Bt maize has on natural enemy communities and specialized pathogens attacking European corn borer, Ostrinia nubilalis (Hübner) (Lepidoptera: Crambidae). Also, there are questions concerning possible influences natural enemies have on development of insect resistance to Bt maize. Scrutiny of Bt crops has resulted in an appreciation of the biodiversity associated with crops, but there is a general lack of knowledge about how corn pest management influences biodiversity in both agricultural and nearby non-agricultural ecosystems. Grower strategies for using Bt maize in the U.S. vary regionally and depend on targeted pest(s), cropping practices, secondary pests, and insect resistance management requirements. A challenge for scientists and educators has been to try to keep grower recommendations uniform and grounded in IPM. Scientists emphasize that Bt is an important tool among many that growers can use in IPM approaches to managing corn pests, that is, to exploit as many strategies for suppressing pest levels as possible and to avoid reliance on any one practice, tactic, chemical, or seed technology. Sweet corn is a high value crop that often is sprayed multiple times to assure product quality. Potential use of biocontrol with Bt sweet corn is particularly promising, since insecticide use in these systems has been dramatically reduced.