title: Relationships between exogenous-toxin quantity and increased biomass of transgenic Bt crops under elevated carbon dioxide.
abstract: Field-OTC experiments were conducted with the goals of ascertaining if increased biomass in Bt transgenic cotton and rice grown under elevated CO(2) results in diminished exogenous-Bt toxin, and assessing the effectiveness of Bt transgenes against lepidopteran pests. Bt cotton responded differently, in terms of Bt-toxin quantity, than Bt rice, and both indicated differences among developmental stages. Dramatic biomass increase significantly diluted Bt-toxin content in 45-DAS ("days after seedling") petioles and shoots and 90-DAS Bt cotton squares, and in the 50-DAS tissues and 100-DAS leaf sheaths of Bt rice. Moreover, the dilution effect was partially responsible for decreased Bt-toxin in these tissues, but not responsible for significant decreases in Bt-toxin in 90-DAS Bt cotton leaves and bolls. Furthermore, elevated CO(2) significantly affected the fitness and performance of Chilo suppressalis, and the susceptible and resistant colonies of Helicoverpa armigera, although adversely affected Bt-gene expression for the transgenic cotton and rice.
authors.affiliation: Department of Entomology, Nanjing Agricultural University, Nanjing 210095, China. fajunchen@njau.edu.cn
authors.forename: Fajun
authors.initials: F
authors.lastname: Chen
authors.forename: Gang
authors.initials: G
authors.lastname: Wu
authors.forename: Feng
authors.initials: F
authors.lastname: Ge
authors.forename: Megha N
authors.initials: MN
authors.lastname: Parajulee
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics; D000818:Animals; D001413:Bacillus thuringiensis / Q000235:genetics; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism / Q000633:toxicity; D001427:Bacterial Toxins / Q000378:metabolism; D018533:Biomass; D002245:Carbon Dioxide / Q000378:metabolism*; D004731:Endotoxins / Q000235:genetics / Q000378:metabolism / Q000633:toxicity; D003368:Gossypium / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism / Q000633:toxicity; D007915:Lepidoptera / Q000187:drug effects; D009036:Moths / Q000187:drug effects; D012275:Oryza / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D010572:Pest Control, Biological / Q000379:methods*; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; D012989:Soil Pollutants; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D002245:Carbon Dioxide