Fourteen Years of Bt Cotton Advances IPM

The pink bollworm, Pectinophora gossypiella (Saunders), first invaded Arizona in 1926 and has been a key pest of cotton, Gossypium hirsutum L., since the early 1960s. A broad range of tactics has been developed to manage this pest including a variety of cultural methods, mating disruption via pheromones, sterile insect release, and plant resistance. Transgenic cotton producing the insecticidal proteins of Bacillus thuringiensis Berliner (Bt) was introduced in 1996 and was rapidly and widely adopted by producers in Arizona. Adoption rose to approximately 86% by 2006 and has been more than 93% since 2007 when the state was granted a U.S. Environmental Protection Agency exemption to eliminate required refuge plantings as part of a regional eradication program. The deployment of Bt cotton for selective control of caterpillars led to dramatic regional reductions in abundance of pink bollworm, and associated crop damage and insecticide use. Bt cotton has also been a key technology enabling more selective and biologically-based control approaches for sweetpotato whitefly, Bemisia tabaci (Gennadius), and western tarnished plant bug, Lygus hesperus Knight, two other keys pests of cotton in Arizona. Overall insecticide use (statewide average number of sprays per hectare) in cotton has dropped 88% since 1995. Some challenges ahead include re-invasion of eradicated zones, maintaining susceptibility of pink bollworm to Bt cotton, the economics of Bt cotton use in a post-eradication future, and a rapidly changing agroecosystem. Resumen. El gusano rosado, Pectinophora gossypiella (Saunders), invadió por primera vez Arizona en 1926 y ha sido una de las plagas principales del algodonero desde principios de los 1960s. Una amplia variedad de tácticas se han implementado para controlar a esta plaga, las que incluyen métodos de cultivo, la disrupción de apareamientos debido a la presencia de feromonas, la liberación de insectos estériles, así como variedades resistentes. El algodonero transgénico que expresa Bacillus thuringiensis Berliner (Bt) fue introducido en 1996 y fue rápidamente adoptado por los agricultores de Arizona. Esta adopción se incrementó el 86% en 2006 y a partir del 2007 ha llegado a 93%, cuando al estado se le otorgó la excepción por parte de la institución a cargo de la protección del medio ambiente Estadounidense (U.S. Environmental Protection Agency) para eliminar el refugio, como parte de un programa de erradicación regional. La utilización de algodonero Bt para el control de ciertos gusanos ha llevado a una ________________________ This article presents the results of research only. Mention of a proprietary product does not constitute endorsement or recommendation for its use by USDA. USDA-ARS, Arid-Land Agricultural Research Center, 21881 North Cardon Lane, Maricopa, AZ 85138. University of Arizona, Department of Entomology, Maricopa Agricultural Center, 37860 West SmithEnke Road, Maricopa, AZ 85138.