title: Sustained susceptibility of pink bollworm to Bt cotton in the United States.
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 y. 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.
authors.affiliation: Department of Entomology; University of Arizona, Tucson, AZ, USA. brucet@cals.arizona.edu
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Tabashnik
authors.forename: Shai
authors.initials: S
authors.lastname: Morin
authors.forename: Gopalan C
authors.initials: GC
authors.lastname: Unnithan
authors.forename: Alex J
authors.initials: AJ
authors.lastname: Yelich
authors.forename: Christa
authors.initials: C
authors.lastname: Ellers-Kirk
authors.forename: Virginia S
authors.initials: VS
authors.lastname: Harpold
authors.forename: Mark S
authors.initials: MS
authors.lastname: Sisterson
authors.forename: Peter C
authors.initials: PC
authors.lastname: Ellsworth
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Dennehy
authors.forename: Larry
authors.initials: L
authors.lastname: Antilla
authors.forename: Leighton
authors.initials: L
authors.lastname: Liesner
authors.forename: Mike
authors.initials: M
authors.lastname: Whitlow
authors.forename: Robert T
authors.initials: RT
authors.lastname: Staten
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Fabrick
authors.forename: Xianchun
authors.initials: X
authors.lastname: Li
authors.forename: Yves
authors.initials: Y
authors.lastname: Carrière
mesh_terms: D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics*; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics; D018556:Crops, Agricultural; D004731:Endotoxins / Q000235:genetics; D003368:Gossypium / Q000235:genetics* / Q000469:parasitology; D006460:Hemolysin Proteins / Q000235:genetics; D007305:Insecticide Resistance; D007306:Insecticides; D009036:Moths / Q000502:physiology*; D010572:Pest Control, Biological; D030821:Plants, Genetically Modified; D019076:Transgenes; D014481:United States
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis