Citronella is not a Repellent to Africanized Honey Bees Apis mellifera L. (Hymenoptera: Apidae)

Abstract

Experiments were performed investigating citronella (Cymbopogon winterianus Jowitt) as a repellent to Africanized honey bees Apis mellifera (L.) (Hymenoptera: Apidae) in Brazil. Results indicated that citronella is not a repellent. Bees exposed to a 100% concentration of citronella easily learned a Pavlovian association between citronella and feeding. In a second experiment, conditioned suppression was used to evaluate the effect of citronella on a proboscis extended by learning and by sucrose stimulation. Performance was indistinguishable from the application of a novel control odor. The laboratory experiments were confirmed in a field experiment in which citronella was applied directly to individuals foraging on a flower patch. Bees did not fly off flowers when the odor of citronella was applied directly to them relative to a control odor. The value of evaluating potential repellents using learning paradigms is discussed.