The caterpillar pest Helicoverpa zea (also known as cotton bollworm and corn earworm) has evolved resistance to four Bt proteins produced by biotech crops. ALEX YELICH/UA DEPARTMENT OF ENTOMOLOGYResistance to insecticides produced by genetically modified crops is on the rise, according to a study published Wednesday (October 11) in Nature Biotechnology.
For more than 20 years, farmers across the globe have been planting crops, including corn, cotton, and soybeans, that have been genetically modified to express insecticide genes from the bacterium Bacillus thuringiensis (Bt). When susceptible pests munch on these “Bt crops,” they get poisoned. But insects that have developed resistance to Bt toxins can live on undeterred, and that resistance is growing.
“When Bt crops were first introduced in 1996, no one knew how quickly the pests would adapt,” says study coauthor Bruce Tabashnik, head of the University of Arizona (UA) department of entomology, in a release. “Now we have a cumulative total of over 2 billion acres of these crops planted during the past two decades and extensive monitoring data, so we can build ...
