Apis cerana Is Less Sensitive to Most Neonicotinoids, Despite of Their Smaller Body Mass

Multiple stressors and interaction between them may be responsible for the decline of global pollinators. Among them, exposure to neonicotinoids has been getting more attention and has been considered as a main stressor. The Western honey bee (Apis mellifera L.) (Hymenoptera: Apidae) and Chinese indigenous honey bee (Apis cerana F.) (Hymenoptera: Apidae) are two managed honey bee species in China. These two species are widely used in beekeeping, and many wild A. cerana is widely spread in forests and contributes to the ecosystem. It is predicated that A. cerana is more sensitive to insecticides than A. mellifera due to their smaller mass. Here, we found that although the body mass of A. cerana is significantly lower than A. mellifera, the sensitivity of the two species to neonicotinoids are not associated with their body mass but depended on the chemical structure of neonicotinoids. To dinotefuran, the two species showed the similar sensitivity. To acetamiprid, A. mellifera was less sensitive than A. cerana. However, to imidacloprid and thiamethoxam, A. mellifera was more sensitive than A. cerana. These results suggested that the sensitivity of honey bees to neonicotinoids is closely associated with the structure of pesticides, but not with body mass of bees. It is also indicated that the hazards of pesticides to the different pollinators could not be inferred from one species to another.