Biotech Updates

Scientists Explain Why Pest Has Not Evolved Resistance to Bt Maize in EU

May 11, 2016

Spain is the only country in the European Union where Bt maize has been grown continuously on a large scale. The main target insect of Bt maize, the corn borer, has not developed resistance even if Bt maize has been planted since 1998. A study was conducted by Pedro Castañera of Centro de Investigaciones Biológica (CIB), Spain, and colleagues to investigate why.

The researchers used evolutionary models to evaluate the factors that are expected to develop or delay resistance. Results showed that low initial adoption rates and the EU policy decision to replace Event 176 with MON 810 Bt maize were key to delaying resistance evolution. The model results also suggest that if refuge compliance continues at the current 90%, Bt maize might be used sustainably in northeast Spain for at least 20 more years before resistance might happen.

Read the open-access research article in PLos One.