Back in February of this year American and German researchers released a study showing that Monsanto’s genetically modified Bt cotton almost doubled crop yields while requiring less pesticides. But a new study of Bt cotton claims that most Indian farmers who used the GM cotton saw a decline in crop yields by about 35 percent. What gives?
The February study looked at 157 farms that used Bt cotton. The cotton is designed to be especially resistant to the boll weevil which traditionally causes significant crop loss. GM cotton has been used successfully in China, resulting in a 70 percent decline in pesticide use, but India has a far more severe pest problem. That study found that even though Bt cotton was more expensive, farmers who used it still managed to increase their income five-fold.
But the latest study — which the BBC did not bother to identify the source — says that 71 percent of farmers who used the GM cotton found that their yields declined an average of 35 percent compared to farmers who used traditional crop varieties.
The BBC reports that a Monsanto spokesperson ascribed the decline in crop yields to a drought, which would still seem to imply that if the GM cotton is more pest resistant, it might be more sensitive to drought.
Sources:
‘Indian GM cotton a failure’. The BBC, June 6, 2003.
GM cotton doubles yield in India trials. Tim Radford, The Guardian, February 7, 2003.