SUPPRESSION OF QUEEN REARING IN EUROPEAN AND AFRICANIZED HONEY-BEES APIS-MELLIFERA L BY SYNTHETIC QUEEN MANDIBULAR GLAND PHEROMONE

Queen rearing is suppressed in honey bees (Apis mellifera L.) by pheromones, particularly the queen's mandibular gland pheromone. In this study we compared this pheromonally-based inhibition between temperate and tropically-evolved honey bees. Colonies of European and Africanized bees were exposed to synthetic queen mandibular gland pheromone (QMP) for ten days following removal of resident queens, and their queen rearing responses were examined. Queen rearing was suppressed similarly in both European and Africanized honey bees with the addition of synthetic QMP, indicating that QMP acts on workers of both races in a comparable fashion. QMP completely suppressed queen cell production for two days, but by day six, cells containing queen larvae were present in all treated colonies, indicating that other signals play a role in the suppression of queen rearing. In queenless control colonies not treated with QMP, Africanized bees reared 30% fewer queens than Europeans, possibly due to racial differences in response to Feedback from developing queens and/or their cells, Queen development rate was faster in Africanized colonies, or they selected older larvae to initiate cells, as only 1% of queen cells were unsealed after 10 days compared with 12% unsealed cells in European colonies.