Why scientists released billions of sterile moths across American cotton fields to defeat one of agriculture's most destructive pests

Scientists released billions of sterile moths across American cotton fields/Image: AI Generated For much of the twentieth century, the pink bollworm (Pectinophora gossypiella) was one of the greatest threats to cotton farming in North America. The tiny insect caused billions of dollars in crop losses by burrowing into cotton bolls, where its larvae fed on seeds and fibres while remaining largely protected from pesticides. Farmers often had little choice but to spray their fields repeatedly, yet the pest continued to spread and develop resistance to many chemical controls.Instead of relying solely on insecticides, scientists turned to an idea that seemed almost unbelievable, they bred billions more pink bollworms. Beginning in Arizona, specially reared sterile moths were released from aircraft over cotton fields. Unable to produce offspring, these insects gradually reduced wild populations until the pest disappeared from commercial cotton production across theUnited States. The programme is now regarded as one of the most successful examples of biological pest control ever achieved.Why the pink bollworm became one of cotton's most destructive pestsOriginally native to Asia, the pink...