Meeting Abstract

P2.167  Sunday, Jan. 5 15:30  The neonicotinoid pesticide imidacloprid affects motor responses in honey bees. LEVINSON, B.M*; BLATZHEIM, L; BOWER, C.D; POLK, T; IKIZOĞLU, D; KARAHN, A; GUNEŞ, N; ÇAKMAK, I; WELLS, H; HRANITZ, J.M; University of California, San Diego; Southwestern Oklahoma State University; Bloomsburg University; Southern Nazarene University; Uludağ University, Bursa, TURKEY; University of Tulsa blevinso@ucsd.edu

Pesticides and insecticides have been increasingly used in commercial produce and farming for decades. Neonicotinoid pesticides, mimics of nicotine, are being used at a high rate globally and have been implicated as a causal agent in the honey bee colony collapse disorder (CCD). Of the variety of neonicotinoid pesticides currently in use, imidacloprid is by far the most widely used in this class. As a systemic pesticide, imidacloprid is applied to a wide array of crops and is reported in both nectar and pollen used by honey bees at concentrations that should ensure doses lower than the LD50. As a neurological blocker of acetylcholine synapses, the sublethal effects of imidacloprid were expected to manifest as lack of motor control over muscle. Therefore, our goal was to investigate the effect of sublethal doses of imidacloprid on motor coordination of the honey bee. We fed bees sublethal doses of imidacloprid ranging from 1/5 to 1/500 LD50 in 50% sucrose. Control bees were fed 50% sucrose only. At 4 h post-ingestion, honey bees were scored for their motor coordination by assessing the proboscis extension reflex as well as coordination of the antennae, legs, and abdomen. Bees fed doses of imidacloprid higher than 1/100 LD50 showed reduced motor coordination similar to that of thermally stressed honey bees. These results show that imidacloprid, even at doses 1/100th of the LD50, impair basic motor coordination fundamental to locomotion and foraging.