Effects of sublethal exposure to imidacloprid on subsequent behavior of subterranean termite Reticulitermes virginicus (Isoptera : Rhinotermitidae)

Experiments were conducted to determine whether subterranean termites. Reti culitermes virginicus (Banks), previously exposed to sublethal doses of imi dacloprid (Premise), and allowed to recover for 1 wk, demonstrated behavior al aversion to a subsequent exposure. Worker termites experiencing a previo us sublethal but debilitating exposure to imidacloprid-treated sand (either 10 or 100 ppm for 4h) showed no apparent aversion to a second encounter wi th imidacloprid sand under conditions of this experiment. If these laborato ry results hold in the field and termites traveling through a zone of soil treated with imidacloprid are impaired but subsequently recover , they will be just as likely as their naive nestmates to reenter the treated area if their travels take them through the nonrepellent application a second time. Our results also indicate that a sublethal exposure to imidacloprid can af fect termite tunneling behavior. Many worker termites that received an init ial 4-h exposure to 100 ppm imidacloprid-treated sand died, but those that survived tunneled significantly less than did their naive nestmates, as did some termites exposed to 10 ppm imidacloprid.