Does the transgenic Cry1Ac toxin adversely affect the population dynamics of floral-visiting insects in soybean crop?

Abstract

One of the strategies of Integrated Pest Management (IPM)-soybean is the use of genetically modified plants. However, there are concerns about the unknown effects associated with this technology on nontarget organisms. The objective of this study was to determine the population dynamics of species of floral-visiting insects in Bacillus thuringiensis (Bt) and non-Bt soybean. In the experiment, two soybean treatments were assessed, one of soy DM 6563 Intacta and the other BMX Potência RR. Floral-visiting insects were collected in the flowering period every 15 min/h for 12 h/day, every 3 to 4 days. 549 floralvisiting insects (Class Insecta) were collected, comprising 8 orders, 30 families, and 92 species. Of these, 279 were present in the cultivar DM 6563 Intacta and 270 in the cultivar BMX Potência. The most abundant species were Apis mellifera (35.15%), Musca species 1 (10.01%), and Lagria villosa (5.28%). Species composition was similar for the two cultivars. The highest number of species visited the flowers of the cultivars between 8:00 and 11:00 am, while the lowest intensity of visitation occurred between 12:00 and 15:00 pm. After diversity was determined, it was observed that cultivar BMX Potência (non-Bt) had a higher diversity than cultivar DM 6563 Intacta (Bt).

Keywords: Pollinators, species diversity, transgenic