Insect resistance to Bt crops – when is it likely?
A University of Arizona survey of 77 studies, released in 2013, found "well-documented cases of field-evolved resistance to Bt crops in five major pests as of 2010, compared with only one case in 2005.
Armyworm resistant to GE corn is found in Southeast
Researchers confirmed that fall armyworms in North Carolina are resistant to a variety of corn genetically engineered to produce a protein toxic to the insects. It is the first documented occurrence of insect resistance to so-called Bt (Bacillus thuringiensis) corn in 18 years of use, said Entomology Today.