Abstract:
The effects of pesticides on honeybee larvae are less understood than for adult bees, even
though larvae are chronically exposed to pesticide residues that accumulate in comb and food
stores in the hive. We investigated how exposure to a plant alkaloid, nicotine, affects
survival, growth and body composition of honeybee larvae. Larvae of Apis mellifera
scutellata were reared in vitro and fed throughout development on standard diets with
nicotine included at concentrations from 0 to 1000 μg/100 g diet. Overall mortality across all
nicotine treatments was low, averaging 9.8 % at the prepupal stage and 18.1 % at the whiteeyed
pupal stage, but survival was significantly reduced by nicotine. The mass of prepupae
and white-eyed pupae was not affected by nicotine. In terms of body composition, nicotine
affected water content but did not influence either protein or lipid stores of white-eyed pupae.
We attribute the absence of consistent negative effects of dietary nicotine to detoxification
mechanisms in developing honeybees, which enable them to resist both natural and synthetic
xenobiotics.
