An ideal pesticide would kill only pests, leaving all other creatures unharmed. Now biologists have engineered potatoes to be lethal to a major pest called the Colorado potato beetle but harmless to other species, no pesticide required.
Ralph Bock of the Max Planck Institute of Molecular Plant Physiology in Germany has genetically modified potatoes to produce RNA molecules that, when eaten, shut down an important gene in the beetle. The approach is based on a technique known as gene silencing or RNA …