A commercial fungus-based biopesticide impacts survival and recognition system of a tropical social bee

The use of fungus-based biopesticides has grown worldwide as an effective and ecologically sustainable strategy for the control of crop pests, which in turn increases the need to investigate potential harmful effects on non-target organisms in tropical agroecosystems. However, such effects of commercial formulations based on the entomopathogenic fungus Beauveria bassiana on stingless bees, the main pollinators of a wide range of flowering crops, remains largely unexplored. Here, we tested if Boveril^®WP, a commercial bioinsecticide, affects survival, cuticular hydrocarbon profile and social recognition in the stingless bee Scaptotrigona depilis. Combining exposure assay, cuticular hydrocarbon profiling, and lure presentation, we found that this mycopesticide causes the following: (1) lethal effects when topically applied on the thorax (LT₅₀ = 30 min) or abdomen (LT₅₀ = 24 h) of foragers; (2) quantitative changes in cuticular hydrocarbon profile of foragers within 12 h, containing significantly higher proportions of three linear alkanes and one methylated alkane; (3) subtle effect on social recognition by entrance guards, with lower aggression rates toward exposed foragers (nestmates or not), which may facilitate the transmission of lethal pathogens into and among colonies. This study demonstrates the potential incompatibility of a common biopesticide with a native pollinator, thus highlighting the much-needed Integrated Pest and Pollinator Management (IPPM) approaches for the best use of ecological services provided by non-target organisms.