Abstract:  Mushroom bodies (MBs) are insect brain centers involved in learning and other complex behaviors. The proliferation and programmed cell death (PCD) pattern of MBs in the honeybee, Apis cerana cerana, was comparatively studied by using 5-bromo-2-deoxyuridine (BrdU) incorporation and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) technique. The results showed that the MBs are created in their entirety by several neuroblasts per hemisphere. Asymmetric divisions produce a smaller ganglion mother cell (GMC) and regenerate the neuroblast. Kenyon cells in a proliferation cluster are formed through symmetrical division of MB neuroblasts. These neuroblasts divide continuously from early embryogenesis until the late pupal stage. Peduncular neuropil was first visible in the 3rd instar. The calycal neuropil rapidly increased in size during the pupal stage. Extensive apoptosis in the MBs could be detected only within a narrow time window from day 3 to day 6 of the pupal stage during metamorphosis. Extensive apoptosis in the MB proliferative clusters started at about the time when proliferation began to cease. This study provides a theoretical basis for behavioural research.

Key words:  Apis cerana cerana； mushroom body； postembryonic development； proliferation； apoptosis； BrdU, TUNEL