title: The interaction of two-spotted spider mites, Tetranychus urticae Koch, with Cry protein production and predation by Amblyseius andersoni (Chant) in Cry1Ac/Cry2Ab cotton and Cry1F maize.
abstract: Crops producing insecticidal crystal (Cry) proteins from the bacterium, Bacillus thuringiensis (Bt), are an important tool for managing lepidopteran pests on cotton and maize. However, the effects of these Bt crops on non-target organisms, especially natural enemies that provide biological control services, are required to be addressed in an environmental risk assessment. Amblyseius andersoni (Acari: Phytoseiidae) is a cosmopolitan predator of the two-spotted spider mite, Tetranychus urticae (Acari: Tetranychidae), a significant pest of cotton and maize. Tri-trophic studies were conducted to assess the potential effects of Cry1Ac/Cry2Ab cotton and Cry1F maize on life history parameters (survival rate, development time, fecundity and egg hatching rate) of A. andersoni. We confirmed that these Bt crops have no effects on the biology of T. urticae and, in turn, that there were no differences in any of the life history parameters of A. andersoni when it fed on T. urticae feeding on Cry1Ac/Cry2Ab or non-Bt cotton and Cry1F or non-Bt maize. Use of a susceptible insect assay demonstrated that T. urticae contained biologically active Cry proteins. Cry proteins concentrations declined greatly as they moved from plants to herbivores to predators and protein concentration did not appear to be related to mite density. Free-choice experiments revealed that A. andersoni had no preference for Cry1Ac/Cry2Ab cotton or Cry1F maize-reared T. urticae compared with those reared on non-Bt cotton or maize. Collectively these results provide strong evidence that these crops can complement other integrated pest management tactics including biological control.
authors.affiliation: Department of Entomology, Cornell University, New York State Agricultural Experiment Station (NYSAES), Geneva, NY, USA.|Department of Entomology, China Agricultural University, Beijing, China.
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Guo
authors.affiliation: State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Plant Protection and Microbiology, Zhejiang Academy of Agricultural Sciences, Hangzhou, Zhejiang, China.
authors.forename: Jun-Ce
authors.initials: JC
authors.lastname: Tian
authors.affiliation: Department of Entomology, China Agricultural University, Beijing, China.
authors.forename: Wang-Peng
authors.initials: WP
authors.lastname: Shi
authors.affiliation: Department of Agriculture Science, China Agricultural University, Beijing, China.
authors.forename: Xue-Hui
authors.initials: XH
authors.lastname: Dong
authors.affiliation: Agroscope, Institute for Sustainability Sciences ISS, Zurich, Switzerland.
authors.forename: Jörg
authors.initials: J
authors.lastname: Romeis
authors.affiliation: Arid-Land Agricultural Research Center, USDA-ARS, Maricopa, AZ, 85138, USA.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Naranjo
authors.affiliation: Corn Insects and Crop Genetics Research Unit, USDA-ARS, Ames, IA, 50011, USA.|Department of Entomology, Iowa State University, Ames, IA, 50011, USA.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Hellmich
authors.affiliation: Department of Entomology, Cornell University, New York State Agricultural Experiment Station (NYSAES), Geneva, NY, USA. ams5@cornell.edu.
authors.forename: Anthony M
authors.initials: AM
authors.lastname: Shelton
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics; D018556:Crops, Agricultural; D004731:Endotoxins / Q000235:genetics; D005298:Fertility; D003368:Gossypium / Q000235:genetics* / Q000502:physiology; D006460:Hemolysin Proteins / Q000235:genetics; D060434:Herbivory / Q000502:physiology; D019476:Insect Proteins; D007814:Larva; D010572:Pest Control, Biological; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000502:physiology*; D011235:Predatory Behavior / Q000502:physiology; D011956:Receptors, Cell Surface / Q000235:genetics; D018570:Risk Assessment / Q000379:methods; D040102:Tetranychidae / Q000502:physiology*; D003313:Zea mays / Q000235:genetics* / Q000502:physiology
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; C095416:Cry toxin receptors; D004731:Endotoxins; D006460:Hemolysin Proteins; D019476:Insect Proteins; D011956:Receptors, Cell Surface; C030956:insecticidal crystal protein, Bacillus Thuringiensis
keywords: Biological control; Cry1Ac; Cry1F; Cry2Ab; Environmental risk assessment; Tri-trophic exposure