Some insects may be able to develop resistance to genetically modified cotton plants more quickly than expected, rendering the plants obsolete sooner than developer Monsanto anticipated, according to research published in today’s issue of the journal Nature. If follow-up field studies yield similar results, the U.S. EPA would likely have to change its rules regarding genetically modified crops. Biotech executives disputed the study, saying, among other things, that it didn’t replicate actual field conditions. Meanwhile, growing opposition to genetically modified crops seems to be contributing to a less rosy financial outlook for Monsanto.