title: Quercetin interacts with Cry1Ac protein to affect larval growth and survival of Helicoverpa armigera.
abstract: BACKGROUND
  Bt cotton has been widely planted in China for over a decade to control H. armigera, but field surveys indicate increasing resistance in the pest. It has been speculated that accumulating plant secondary compounds in mature cotton may interact with Bt toxins and affect the toxicity of Bt to H. armigera.
  
  
  RESULTS
  Both quercetin, one of the main flavonoids in cotton, and the Bt toxin Cry1Ac protein had significant negative effects on the growth, development and survival of H. armigera when added singly to artificial diet, but their effects were inhibited when added in combination. Quercetin was antagonistic to Cry1Ac toxicity at all tested concentrations.
  
  
  CONCLUSIONS
  The accumulation of quercetin might be one factor contributing to the reduced toxicity of mature Bt cotton plants to H. armigera, and could partially explain the reduced efficacy of Cry1Ac in controlling this pest in the field. © 2015 Society of Chemical Industry.
authors.affiliation: Department of Entomology, China Agricultural University, Beijing, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Entomology, China Agricultural University, Beijing, China.|Shandong Plant Protection Station, Jinan, China.
authors.forename: Xiumin
authors.initials: X
authors.lastname: Guan
authors.affiliation: Department of Entomology, Kansas State University, KS, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Michaud
authors.affiliation: Department of Entomology, China Agricultural University, Beijing, China.
authors.forename: Qingwen
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Entomology, China Agricultural University, Beijing, China.
authors.forename: Xiaoxia
authors.initials: X
authors.lastname: Liu
mesh_terms: D000818:Animals; D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins / Q000494:pharmacology*; D004731:Endotoxins / Q000494:pharmacology*; D003368:Gossypium / Q000469:parasitology; D006460:Hemolysin Proteins / Q000494:pharmacology*; D007306:Insecticides / Q000494:pharmacology*; D007814:Larva / Q000187:drug effects / Q000254:growth & development; D009036:Moths / Q000187:drug effects* / Q000254:growth & development; D011794:Quercetin / Q000494:pharmacology*
chemical_list: D000083722:Bacillus thuringiensis Toxins; D001426:Bacterial Proteins; D004731:Endotoxins; D006460:Hemolysin Proteins; D007306:Insecticides; C030956:insecticidal crystal protein, Bacillus Thuringiensis; D011794:Quercetin
keywords: Bt toxin; Old World bollworm; flavonoid; pest management; plant secondary compound; transgenic plant