Effects of queen weight and requeening on colony development of the bumblebee, (Bombus terrestris L.)

Bombus terrestris L. is an effective pollinator of crops particularly tomato and has been commercially mass reared for pollination in greenhouses for more than two decades. Although the mass rearing techniques have been developed rapidly, there are still several problems such as being short lifespan of the colony in the greenhouse and queen loss occurred in the colony development stages. In this thesis, we investigated the effects of requeening on colony development, prevention of colony and queen losses in B.terrestris. Moreover, the relationships between pre and post diapause queen weights and colony development traits were also determined. All queens and colonies were fed with ad-libitum same sugar syrups and pollen diets and reared under standard laboratory conditions (27 ± 1 oC, 55 ± 5 RH%). Immediately after colony foundation phase, a total of 60 colonies were randomly assigned to one of three treatment groups to test for effects of requeening. The first group (S) involved colonies that were requeened with newly hibernated queens after all the workers in the first brood had emerged. In the second group (P), we requeened the colonies with newly hibernated queens when reached some 40 workers and the third group (K) retained their original queens and served as a control group. Queen acceptance (requeening success) rate was much lover in the P group (45%) than in the S group (90%). Colony lifespan was significantly longer in the P group (83.57 ± 3.55 days) than in the K group (76.70 ± 2.76 days). Pre and post-diapause weights did not have a significant effect on examined colony development traits. Results show that requeening technique can be used and provides an option to overcome colony losses in B. terrestris mass rearing. KEYWORDS: Bumblebee, B. terrestris, Requeening, Colony traits