Pink Bollworm

Pectinophora gossypiella — the pink bollworm — was historically one of the most economically important COTTON PESTS in the world and one of about 4,500 species in family Gelechiidae (the twirler moths). The species is native to South Asia and was accidentally spread globally with cotton commerce in the 1800s-early 1900s — establishing as a major cotton pest across all major cotton-growing regions worldwide (Asia, Africa, Mediterranean, Americas, Australia). The species was a particularly destructive pest in the southwestern US (Arizona, California, New Mexico, west Texas) from the 1910s through the 2010s. Adults are 1.5-2 cm wingspan, small inconspicuous tan-brown moths with dark wing markings. Larvae are 1-1.5 cm long, pale-pink-to-dark-pink (the source of the common name) with darker head capsule, and BORE INTO COTTON BOLLS to feed on developing cotton seeds and damage developing cotton fibers. Pink bollworm damage causes massive losses in cotton yield (damaged bolls have reduced cotton fiber and seed value) and quality (residual bollworm material contaminates harvested cotton lint). The species is the FOUNDATIONAL CASE STUDY in modern AREA-WIDE PEST ERADICATION. The southwestern US pink bollworm eradication program was launched in the late 1980s and integrated multiple control approaches: (1) Bt COTTON deployment (Bt cotton became commercially available in 1996 and provides direct in-plant control of pink bollworm — Bt cotton became dominant in southwestern US cotton acreage by the early 2000s); (2) STERILE INSECT TECHNIQUE (SIT) — mass-rearing and releasing sterilized male pink bollworms to disrupt wild population reproduction; the SIT program operated continuously over the southwestern US cotton-growing region from the 1990s through 2018, with billions of sterile pink bollworms released annually); (3) PHEROMONE MATING DISRUPTION (synthetic pheromone applications that saturate the air with mating pheromones, preventing males from finding females); and (4) intensive surveillance and quarantine. The combined eradication program cost over $400 MILLION across two decades but achieved EFFECTIVE ERADICATION OF PINK BOLLWORM from the southwestern US and northern Mexico in 2018 — one of the most successful agricultural pest eradication programs in modern history. The species remains a major pest across the rest of its global range (especially in India, where Bt cotton resistance evolution has reduced Bt cotton effectiveness over the past 10 years), but the southwestern US eradication is featured in essentially every modern agricultural entomology curriculum as a flagship example of integrated pest eradication. The species is harmless to humans but is one of the most-cited cases in modern agricultural entomology of successful invasive pest eradication.