Scientists have already created genetically modified crops that produce proteins that are toxic to the pests that eat them. Now they have gone a step further and created plants that literally rewrite the genetic code of the insects that eat them. The genetically modified crops use a process called RNA interference:

RNA interference occurs naturally in animals ranging from worms to humans. It’s a process whereby double-stranded RNA copies of specific genes prevent cells from translating those genes into proteins. The new genetically modified plants carry genes for double-stranded RNA targeted to particular insect genes…

Researchers at the Chinese Academy of Sciences, in Shanghai, made cotton plants that silence a gene that allows cotton bollworms to process the toxin gossypol, which occurs naturally in cotton. Bollworms that eat the genetically engineered cotton can’t make their toxin-processing proteins, and they die. Researchers at Monsanto and Devgen, a Belgian company, made corn plants that silence a gene essential for energy production in corn rootworms; ingestion wipes out the worms within 12 days.