title: Effects of Cry34/35Ab1 corn on the survival and development of western corn rootworm, Diabrotica virgifera virgifera.
abstract: BACKGROUND
  The western corn rootworm, Diabrotica virgifera virgifera LeConte, is a major agricultural pest that is managed with transgenic corn, Zea mays L., expressing genes from Bacillus thuringiensis Berliner (Bt). The effects of Bt corn producing Cry34/35Ab1 (event DAS-59122-7) and entomopathogens on the survival and development of larval D. v. virgifera were examined in laboratory, field and greenhouse experiments.
  
  
  RESULTS
  Larvae preferred non-Bt over Bt corn in a laboratory experiment, and there was higher recovery from non-Bt corn than from Bt corn in a field experiment. In a greenhouse study, survival at 17 days did not differ significantly among non-Bt corn, Bt corn and a blend of Bt and non-Bt corn, but development was delayed on Bt corn. Older larvae fed non-Bt corn had lower survival when entomopathogenic nematodes were added, but no other effects of pathogen were detected.
  
  
  CONCLUSIONS
  Bt corn producing Cry34/35Ab1 delayed larval development of D. v. virgifera and deterred feeding. In a mixture of Bt and non-Bt corn, larval development and survival were similar to non-Bt corn alone, suggesting that non-Bt plants in a blended refuge or a pure stand may produce a similar number of adult insects, and that timing of adult emergence may also be similar.
authors.affiliation: Entomology Department, Iowa State University, Ames, IA, USA. ryne0008@umn.edu
authors.forename: Melissa L
authors.initials: ML
authors.lastname: Rudeen
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Gassmann
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001517:Coleoptera / Q000254:growth & development* / Q000502:physiology; D004731:Endotoxins / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D006460:Hemolysin Proteins / Q000235:genetics* / Q000378:metabolism; D007305:Insecticide Resistance; D010572:Pest Control, Biological / Q000379:methods*; D010935:Plant Diseases / Q000235:genetics / Q000276:immunology / Q000469:parasitology*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000276:immunology / Q000469:parasitology*; D003313:Zea mays / Q000235:genetics / Q000276:immunology / Q000469:parasitology*
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis