Most scholarship on the closely-watched case of genetically modified Bacillus thuringiensis (Bt) cotton in India has focused on short-term impacts and has also ignored other major changes in India’s cotton agriculture. This Perspective combines several data sources over a 20-year span to provide long-term comparisons of Bt adoption with yields and other inputs at both countrywide and state-specific scales. Bt cotton adoption is shown to be a poor indicator of yield trends but a strong indicator of initial reductions in pesticide use. Yield increases correspond to changes in fertilizer and other inputs. Bt cotton has continued to control one major cotton pest, but with Bt resistance in another pest and surging populations of non-target pests, farmers now spend more on pesticides today than before the introduction of Bt. Indications are that the situation will continue to deteriorate.

在印度，受到密切关注的转基因苏云金芽孢杆菌（Bt）棉花案例的大多数奖学金都集中在短期影响上，也忽略了印度棉花农业的其他重大变化。该观点结合了20年间的多个数据源，以长期比较Bt的采用与全国范围和特定州范围内的收益和其他投入。事实证明，采用转Bt棉花不能很好地指示单产趋势，但是可以很好地表明农药用量的最初减少。产量增加对应于肥料和其他投入物的变化。转基因棉花继续控制一种主要的棉花害虫，但转基因棉花由于另一种害虫具有抗药性，并且非目标害虫数量激增，因此，如今农民比使用Bt之前花费更多的农药。有迹象表明情况将继续恶化。