Reproductive Potential Difference of Artificially Inseminated and Naturally Mated Honey Bee Queens (Apis mellifera L.)

Sammanfattning: Apis mellifera L. is the only commercially cultivated bee species in Bangladesh nowadays and has been practicing for migratory beekeeping since 1990. Notably, without taking initiatives to improve the bee stocks, intensified beekeeping has been making the species vulnerable to different threats of diseases, pests and inbreeding depression. Reproductive potentiality of the queens has been declining severely. The investigation was carried out to diagnose present problems regarding reproductive potentiality of the queen bees and finding out the possible solutions. Firstly, 56 numbers of naturally mated queens (Apis mellifera L.) were collected from problematic and non-problematic hives from three districts of Bangladesh. Samples were weighed, body length and thorax width were measured, and dissected to study spermathecae appearance. Average queen body weight (160.75±3.65 mg) was found much lower than the earlier studies in different countries. Moreover, 32.33% spermathecae of the queens were found poor in appearance. Again, 3 different queen rearing and mating procedures were applied in 12 replications each: naturally mated queen (NM), grafted and naturally mated queen (GNM) and grafted and artificially inseminated queen (AIQ). NM and GNM queens were allowed to mate naturally where AIQ queens were inseminated artificially in the laboratory. Interestingly, GNM (196.65±3.13 mg) and AIQ(196.55±2.41 mg) queens were significantly heavier than the NM (159.07±6.94 mg) queens. Likewise, their spermathecae radius, respective workers, drones, brood occupation area showed much better strength than the NM queens, though, latency period of AIQ queens were higher. Since grafted queens were reared with good larvae and implemented in artificial queen cups with increased brood support, hence that could make the queens heavier and reproductively more potential, whereas NM queens were left to grow naturally and found less potential. The findings will encourage beekeepers for practicing grafting procedure as the better queen rearing procedure in field condition. However, the procedure of AIQ queens also could be used for stock improvement and bee research because of its control mating system.