Meeting Abstract
P2.166 Sunday, Jan. 5 15:30 The effect of imidacloprid on sucrose sensitivity of the honey bee proboscis extension reflex POLK, T.J.*; BOWERS, C.; CAKMAK, I.; HRANITZ, J.M.; Southern Nazarene University; Bloomsburg University of Pennsylvania; Uludag University, Bursa, TURKEY trpolk@mail.snu.edu
The proboscis extension reflex (PER) is an important motor program integrated (with motor coordination of locomotion, other feeding reflexes, memory, learning, and social communication) in the honey bee feeding behavior. In the PER, antennal stimulation with sugar solution, nectar in nature, elicits extension of the proboscis for feeding. Honey bees are very sensitive to sucrose concentration in solutions and can distinguish between nectar rewards in nature and in the laboratory. A sucrose sensitivity test has been widely used in studies of the effects of pesticides on honey bees. Our study investigated the effect of sublethal doses, ranging from 1/5 to 1/500 of the LD50 reported for imidacloprid, on the PER of Anatolian honey bees (Apis mellifera anatoliaca) in a Turkish apiary. We tested the PER using 0% sucrose (water), 10% sucrose, and 30% sucrose solutions at 1h before and after the administration of imidacloprid to harnessed honey bees. Bees in our study exhibited a scaled response to the different sucrose solutions, with a higher rate of response to 30% sucrose solution than the 10% sucrose solution. Repeated measures ANOVA of the PER tests revealed that sublethal doses of imidacloprid at 1/5 LD50 impaired the sucrose sensitivity response in honey bees (Wilke’s Lamba=0.549, F=2.819, P=0.0006). At lower doses of imidacloprid (<1/5 LD50), bees did not perform differently than controls. Our results show that sublethal doses of this commonly used neonicotinoid pesticide can impair an important motor reflex in honey bee feeding behavior. These results, along with the effects of imidacloprid on motor coordination, indicate impairment at different levels (PER, motor coordination) of the integrated behavior of foraging in honey bees.
