Cotton is an important cash crop for many smallholder farmers in low- and middle-resource settings. Yet it remains particularly susceptible to insects that can decrease or even destroy yields. Farmers often use expensive and environmentally unsafe pesticides to protect their crops. As a result, cotton production is associated with considerable negative environmental and economic consequences for farmers and their communities.
Bt cotton, a genetically modified seed introduced in the 1990s, is resistant to many common cotton-attacking insects. While it does not affect all possible cotton pests, it does significantly decrease the amount of insecticide required to protect crops. Bt cotton was introduced in Argentina in 1998, where insects affected by Bt cotton are common and farmers could benefit from its use. However, high seed prices prevented widespread adoption. Thus, while the benefits of Bt cotton have been demonstrated elsewhere, the impact for farmers and the environment in Argentina is not well understood.
Researchers used 2001 survey data from 299 farmers – 89 who had adopted Bt cotton and 210 who had not – in two major cotton-growing provinces to determine the effects on pesticide use and farmers’ yields. Surveyed farms are largely representative of cotton producers nationally in that it is primarily large-scale farms that have adopted Bt cotton while smallholders have not. Among Bt adopters that also cultivated other cotton, use and yield differences within farms were also measured. In addition to general data on farm and household characteristics, the survey included detailed questions about input–output use in cotton cultivation for the 1999/2000 and 2000/2001 growing seasons. The effects of Bt cotton on pesticide use and yield were estimated by comparing the differences in pesticide use and productivity on Bt and non-Bt plots for both growing seasons, controlling for observable household, farm and plot characteristics.
Results and Policy Implications
The researchers found that Bt cotton adopters applied pesticides less frequently and, when used, they applied 55 percent leading to improved environmental conditions. Bt adoption also increased cotton yields, adopters had yield increases of 32 percent – 506 kg per hectare. These large gains are due, at least in part, to the relatively low use of insecticide in Argentina coupled with the significant number of pests. Bt adopters avoided crop destruction due to common pests. This suggests that smallholder farmers, who use the least amount of pesticide or insecticides, may benefit the most from Bt adoption. The net yield gain may be as high as 42 percent. Simulation models run by the researchers also indicate that the benefits of Bt cotton adoption are likely to be sustainable; as long as application guidelines are followed it is unlikely that insects will develop resistance to Bt cotton. While more research is necessary to identify the long-term impacts, this study contributes to the literature that pest-resistant crops may have positive economic and environmental effects for farmers.
Photo credit: Abhishek Srivastava via Flickr