Effect of the Cry1, Cry2 and Vip3 protein combinations on the control of Anticarsia gemmatalis (Erebidae) and Chrysodeixis includens (Noctuidae) Lepidoptera

Abstract

The transgenic soybean expressing the cry1Ac insecticidal gene of the Bacillus thuringiensis bacterium has been widely adopted in agriculture. This bacterium acts as an efficient control agent of pest insects due to the expression of different proteins with entomopathogenic activity such as Cry and Vip. This study investigates the toxicity and mode of interaction between the Cry1Ab, Cry1Ac, Cry2Aa, Cry2Ab and Vip3Aa proteins against Chrysodeixis includens and Anticarsia gemmatalis larvae. The combination of the Cry1Ac, Cry2Aa and Vip3Aa toxins had a synergistic effect for C. includens, however, only Vip3Aa and Cry2Aa exhibited synergistic interaction against A. gemmatalis. Cry1Ab and Cry1Ac proteins have been shown to share receptors with the two species tested, however, Cry1Ac does not share binding sites with Cry2Aa, Cry2Ab, and Vip3Aa in both species. Besides helping the resistance management to B. thuringiensis proteins, the combination of Cry and Vip proteins can increase toxicity through synergistic action.