Author(s): Steve Whyard
Publication: PLANT SCIENCE
Abstract: Insects cost the agricultural sector bil- lions of dollars every year in lost crop yields and insecticide expenditures. The continued use of chemical insecticides has inadvertently selected for more resistant pest strains, prompting higher doses and more frequent applications to control them. The advent of transgenic plants, such as those expressing insecticidal Bacillus thuringiensis (Bt) toxins, reduces the use of chemicals while offering protec- tion to some crops (1), but not all insects are affected by Bt toxins, and continued use of Bt technologies will eventually see the rise of Bt-resistant insects. To stay ahead of the pests will require additional technologies. On page 991 of this issue, Zhang et al. (2) describe a clever modification to an existing transgenic plant technology that produces insecticidal RNAs. The trick is to express lethal RNA in the plant’s photosynthetic or- ganelles, the chloroplasts.