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ARS Home » Pacific West Area » Parlier, California » San Joaquin Valley Agricultural Sciences Center » Crop Diseases, Pests and Genetics Research » Research » Publications at this Location » Publication #277333

Title: Sustained susceptibility of Pink Bollworm to Bt cotton in the United States

Author
item TABASHNIK, BRUCE - University Of Arizona
item MORIN, SHAI - Hebrew University
item UNNITHAN, GOPALAN - University Of Arizona
item YELICH, ALEX - University Of Arizona
item ELLERS-KIRK, CHRISTA - University Of Arizona
item HARPOLD, VIRGINIA - University Of Arizona
item Sisterson, Mark
item ELLSWORTH, PETER - University Of Arizona
item DENNEHY, TIMOTHY - Bayer Crop Sciences, Germany
item ANTILLA, LARRY - Arizona Cotton Research And Protection Council
item LIESNER, LEIGHTON - Arizona Cotton Research And Protection Council
item WHITLOW, MIKE - Arizona Cotton Research And Protection Council
item STATEN, ROBERT - Animal And Plant Health Inspection Service (APHIS)
item Fabrick, Jeffrey
item LI, XIANCHUN - University Of Arizona
item CARRIERE, YVES - University Of Arizona

Submitted to: GM Crops
Publication Type: Literature Review
Publication Acceptance Date: 4/10/2012
Publication Date: 7/1/2012
Citation: Tabashnik, B., Morin, S., Unnithan, G., Yelich, A., Ellers-Kirk, C., Harpold, V., Sisterson, M.S., Ellsworth, P., Dennehy, T., Antilla, L., Liesner, L., Whitlow, M., Staten, R., Fabrick, J.A., Li, X., Carriere, Y. 2012. Sustained susceptibility of Pink Bollworm to Bt cotton in the United States. GM Crops. 3:194-200.

Interpretive Summary: Crops genetically engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) kill some key pests and are used extensively worldwide. Benefits of using Bt crops may include reduced insecticide use, regional pest suppression, increased yield, and increased profitability. However, evolution of resistance by target pests threatens to negate these benefits. The pink bollworm is a major cotton pest in many parts of the world and is targeted by transgenic Bt cotton. In China, the frequency of resistance to Cry1Ac has increased, but control failures have not been reported. In western India, pink bollworm resistance to Cry1Ac has caused widespread control failures of Bt cotton. By contrast, in the state of Arizona in the southwestern United States, monitoring data from bioassays and DNA screening demonstrate sustained susceptibility to Cry1Ac for 16 years. Here, factors affecting successful use of Bt cotton against pink bollworm in Arizona are reviewed. From 1996-2005, the main factors that delayed resistance in Arizona appear to be abundant refuges of non-Bt cotton, recessive inheritance of resistance, fitness costs associated with resistance, and incomplete resistance. From 2006-2011, refuge abundance was greatly reduced in Arizona, while mass releases of sterile pink bollworm moths were made to delay resistance as part of a multi-tactic eradication program.

Technical Abstract: Evolution of resistance by pests can reduce the benefits of transgenic crops that produce toxins from Bacillus thuringiensis (Bt) for insect control. One of the world's most important cotton pests, pink bollworm (Pectinophora gossypiella), has been targeted for control by transgenic cotton producing Bt toxin Cry1Ac in several countries for more than a decade. In China, the frequency of resistance to Cry1Ac has increased, but control failures have not been reported. In western India, pink bollworm resistance to Cry1Ac has caused widespread control failures of Bt cotton. By contrast, in the state of Arizona in the southwestern United States, monitoring data from bioassays and DNA screening demonstrate sustained susceptibility to Cry1Ac for 16 years. From 1996-2005, the main factors that delayed resistance in Arizona appear to be abundant refuges of non-Bt cotton, recessive inheritance of resistance, fitness costs associated with resistance, and incomplete resistance. From 2006-2011, refuge abundance was greatly reduced in Arizona, while mass releases of sterile pink bollworm moths were made to delay resistance as part of a multi-tactic eradication program. Sustained susceptibility of pink bollworm to Bt cotton in Arizona has provided a cornerstone for the pink bollworm eradication program and for integrated pest management in cotton. Reduced insecticide use against pink bollworm and other cotton pests has yielded economic benefits for growers, as well as broad environmental and health benefits. We encourage increased efforts to combine Bt crops with other tactics in integrated pest management programs.