title: [Investigation of different dosages of inserted Bt genes and their insect-resistance in transgenic Bt cotton].
abstract: The plants with various dosages of inserted Bt genes were developed by intercrossing among transgenic Bt lines in which Bt genes were inserted in different chromosomes, and commercial non-transgenic Bt varieties. Laboratory bioassay of insect-resistance and Bt toxin protein assays with ELISA were used to detect efficacy to bollworm in different cotton growing stages. As transgenic Bt insect-resistant cotton, temporal difference of resistance existed in plants converging on different dosages of inserted Bt genes, i.e., there was a declining level of efficacy with plant age as the mortality (%) of Helicoverpa and Bt toxin protein expressional level decreased gradually, when analyzed with leaves from the main stem. Our research also revealed that the insect-resistance of converging 4 Bt genes plants was decreased due to homozygous suppression.
authors.affiliation: Cotton Research Institute, Nanjing Agricultural University, Key Laboratory for Crop Genetics and Germplasm Enhancement, Ministry of Education, Nanjing 210095, China.
authors.forename: W Z
authors.initials: WZ
authors.lastname: Guo
authors.forename: J
authors.initials: J
authors.lastname: Sun
authors.forename: Y F
authors.initials: YF
authors.lastname: Guo
authors.forename: T Z
authors.initials: TZ
authors.lastname: Zhang
mesh_terms: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000235:genetics*; D001427:Bacterial Toxins; D004731:Endotoxins / Q000235:genetics*; D018628:Gene Dosage; D003368:Gossypium / Q000235:genetics*; D006460:Hemolysin Proteins; D010572:Pest Control, Biological; D030821:Plants, Genetically Modified
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004731:Endotoxins; D006460:Hemolysin Proteins; C030956:insecticidal crystal protein, Bacillus Thuringiensis