Plantings of cotton bioengineered to produce its owninsecticide against bollworms, a major cause of crop failure, sustained littlebollworm damage until this year. Thisyear the plantings are being seriously damaged by bollworms. Bollworms, however, are not necessarilydeveloping resistance to the cotton’s insecticide. Bollworms breed on corn, and last year morecorn than usual was planted throughout cotton-growing regions. So it is likely that the cotton is simplybeing overwhelmed by corn-bred bollworms.