Tuesday, April 7, 2009
Transgenic sweet corn containing the genes for expression of Bacillus thuringiensis toxins has been developed and is actually in the marketplace in the European Union and North America. B. thuringiensis (Bt) is a naturally-occurring bacterium that was found to produce exotoxins with insecticidal properties. The HD-1 strain of Bt was the first microbe to be successfully commercialized and used in caterpillar control, and it continues to be used as a microbial insecticide. In fact, several other strains of the bacterium have been developed for control of beetles, flies and mosquitoes. The genes for expression of these toxins have been identified, isolated and inserted into the genomes of crop plants. As susceptible insects feed upon the plant, they also consume the insecticidal toxin(s). Transgenic cotton and maize with the Bt toxin trait are now commonly grown in North America. Sweet corn is commonplace in our supermarkets, local markets, and on our tables. Will Bt sweet corn be the variety of choice for producers who supply our markets and our tables with the summer delicacy? What are the risks and the benefits for producers and consumers?