Effects of Bt crops on non-target insect pests

Abstract

The long-term large-scale planting of genetically modified (GM) crops may have potential impacts on the health and stability of agricultural ecosystems while benefitting agricultural production. Bt proteins expressed in Bt crops have a good control on target pests. However, non-target insects that are not susceptible to Bt toxins may have increased populations rapidly, causing significant damage to crops. With the long-term continued cultivation of insect-resistant GM crops, different reports and views on the amounts of pesticide applications have been reported. Based on existing research, we reviewed the characteristics and status of non-target insect pest outbreaks and analyzed the main causes of the outbreaks (such as insecticide use, de-crease of natural enemies, and species replacement). In addition, we discussed the effects of GM crops on non-target pests over long-term cultivation using Bt corn and cotton as examples. Given the existing prob-lems of non-target insect outbreaks due to commercial applications of Bt crops, further studies on monitoring the efficacies of insect-resistant GM crops are necessary to prevent outbreaks of non-target pests needed for sustainable agriculture.