| Transgenic plants producing insecticidal protein derived from Bacillus thuringiensis (Bt) have been widely adopted since their commercial introduction in 1996. In 2009, 25 countries planted 134 million ha of transgenic crops. The widespread adoption of such plants has reduced use of conventional insecticides while attaining yield gains, thus providing economic, environmental and human health benefits. Because of Bt crops’ high pest control efficacy, there is concern that pests will develop resistance to Bt toxins so that Bt crops are less or no longer effective. To delay the evolution of resistance, the U.S. Environmental Protection Agency (EPA) currently requires Bt crop growers to also plant non-Bt (conventional) crops on a minimum percentage of their... |
