A STRAIN of genetically modified cotton cuts the numbers of a devastating moth pest and could eventually eliminate it, the longest trial of the GM crop to date has found. But for this to happen farmers need to ensure they also plant enough conventional cotton.
In 1992, Arizona farmers began planting cotton that produces a toxin from a soil microbe called Bacillus thuringiensis. The cotton kills pink bollworm, the larva of the moth Pectinophora gossypiella. It was designed as an alternative to pesticide sprays, which allow pests to bounce back between each application.
Since then Yves Carrière, an entomologist at…
