Efficacy of Bacillus thuringiensis (Bt) maize expressing Cry1F, Cry1A.105, Cry2Ab2 and Vip3Aa20 proteins to manage the fall armyworm (Lepidoptera: Noctuidae) in Brazil

Abstract

Recommendations to manage the impact of Spodoptera frugiperda (Lepidoptera: Noctuidae) to maize production include the use of Bt crops where approved, combined with the adoption of integrated pest management (IPM) and insect resistance management (IRM) practices. This study evaluated the efficacy of Bt maize expressing proteins Cry1F + Cry 1A.105 + Cry2Ab2 + Vip3Aa20 to control S. frugiperda under field conditions in Brazil. This Bt maize technology effectively managed seedling cutting injury, significantly reduced foliar feeding and achieved near 100% protection from kernel-feeding caused by both a Cry1F-resistant strain and a field-collected population of S. frugiperda. Consistent field-collected data across several years and planting regions suggest that this Bt maize technology will be an important tool for the effective management of all important feeding injury types caused by S. frugiperda in Brazil. As with any Bt maize hybrid, its implementation within IPM and IRM practices should help growers maintain maize crop sustainability in Brazil.