Boll Drop Problems in Roundup-Resistant Cotton

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Farmers in the Mississippi Delta had serious and unexpected problems with Monsantos new Roundup Ready cotton during the 1997 growing season. Introduced commercially this year by Monsanto and Delta and Pine Land seed company, the cotton is genetically engineered to tolerate the pesticide company's best-selling weed killer, glyphosate (Roundup). In early August, some Roundup Ready cotton growers began finding deformed bolls and bolls that dropped off the plants. By fall, nearly 30,000 acres in Mississippi alone were affected. Some growers face losses of $500,000 to $1,000,000. About one-fourth of the almost 200 Mississippi farmers licensed to grow the transgenic cotton have taken their complaints to the state Seed Arbitration Council, as a first step in trying to recoup expected losses. Once the Council evaluates this fall's yield data and issues rulings, farmers are free to take their cases to court.

Company and university scientists are searching for clues to what went wrong with the transgenic cotton. So far they have been able to establish that the boll problems are associated with Roundup Ready cotton, but only 20% of the cotton with the new gene is affected. Investigators are looking for other factors such as soil type, weather conditions, and Roundup applications that might have interacted with the engineered gene to cause the abnormalities. Whatever the mechanism turns out to be, boll development is not obviously related to herbicide resistance and would not have been predicted as an outcome of adding a resistance gene. The boll problems appear to contradict industry claims that gene splicing is a precise technology which allows scientists to reliably predict risks based on knowledge about the added genes.

The abnormal boll development apparently escaped detection under the U.S. Department of Agriculture's (USDA's) oversight program. Within the federal regulatory framework for biotechnology, the Department is charged with determining that transgenic crops are safe for agriculture and the environment before allowing them to be commercialized. The Roundup Ready cotton was approved after passing USDA's field testing and commercialization requirements for genetically engineered crops. This is the second time in two years that one of Monsanto's transgenic crops has suffered a performance failure that was apparently not revealed during field testing. Last summer, the company's Bt cotton failed to meet many farmers' expectations that it would control the cotton bollworm.