摘要
Genetically engineered crops simultaneously produce defensive allelochemi-cals and Bacillus thuringiensis(Bt)toxin proteins to kill some of the world's most devastating insect pests.How the two types of toxins,when ingested sequentially or simultaneously,interact at both lethal and sublethal doses in these pests remains underexplored.Here,we examined the toxicological interactions between the Bt toxin Cry 1 Ac and the flavonoid allelochemical flavone in Helicoverpa armigera.Simultaneous exposure of H.armigera neonates to lethal doses(LC25)of Cry 1 Ac and flavone caused a mortality significantly higher than that of either toxin alone and their expected additive mortality.Preexposure for 24 h to a sublethal dose(LC10)of Cry 1 Ac followed by 6-d simultaneous exposure to the same dose of Cry 1 Ac plus a lethal dose(1.6 mg/g diets,LC50)of flavone resulted in a mortality significantly higher than that of the LC50 dose of flavone alone and the expected additive mortality of the LC50 dose of flavone plus the LC10 dose of Cry 1 Ac.One-day preexposure to the sublethal dose(LC10)of flavone followed by 6-d simultaneous exposure to the LC50 dose(6 ng/cm2)of Cry 1 Ac plus the LC25 dose of flavone yielded a mortality significantly higher than that of the LC50 dose of Cry 1 Ac but similar to the expected additive mortality of the LC50 dose of Cry 1 Ac plus the LC50 dose of flavone.The results suggest that Cry 1 Ac induces and synergizes the toxicity of flavone against H.armigera larvae.
基金
supported by the USDA National Institute of Food and Agriculture Hatch Project(No.ARZT-1370680-R31-172)
National Science Foundation of China(NSFC)-Henan Joint major grant(No.U2004206)
Key Scientific Research Projects of Colleges and Universities in Henan Province(No.21A210027)
State Key Laboratory of Cotton Biology Open Fund(No.CB2020A06).
作者简介
Correspondence:Xianchun Li,Department of Entomology and BI05 Institute,University of Arizona,Tucson,AZ 85721,USA.Tel:(520)626-1749,fax:(520)621-1150,email:lxc@email.arizona.edu;Correspondence:Zhongyuan Deng,School of Agricultural Sciences,Zhengzhou University,Zhengzhou 450001,China.Tel:+860371-67785095,Email:dengzhongyuan@outlook.com。
