Journal of Apicultural Science

Causes of the lack of diapause in bumble bee females (Bombus Latr., Apoidea)

Journal of Apicultural Science. Volume 46, Issue 1, Pages 31-40, ISSN (Print) 1643-4439
The study was performed at the Chair of Economic Insects, Agricultural University, Poznań. The objective of the study was to determine the causes of the failure of bumble bee females to undergo diapause.
Ninety-two diapausing queens and 89 non-diapausing queens were reared in the laboratory. In addition, 40 naturally overwintered queens were caught for analysis. All queens were examined for the following characteristics: ovary size, volume and filling of spermathecae, and dry matter of the fat body.
Of the anatomical characteristics of the reproductive organs of bumble bee females that may have significantly affected the occurrence of diapause ovary length and filling of spermathecae were of prime importance. The mean values of those characteristics were significantly higher in diapausing queens than in non-diapausing queens. The mean length of both ovaries and the number of sperms in the spermathecae were significantly higher in naturally reared queens compared to those from the laboratory rearing which may have been the reflection of an imperfect understanding of the requirements of bumble bee colonies reared under laboratory conditions.
Ovary width and spermatheca volume have no influence on the occurrence of diapause in bumble bee females as no statistical differences for mean values of those characteristics were found in diapausing vs. non-diapausing queens.
The size of the fat body influences the occurrence of diapause. The diapausing queens developed a fat body with a significantly higher dry weight meaning that they were better prepared to survive the diapause than the non-diapausing queens.
Bumble bees, diapause, ovaries, spermatheca, fat body
Submit your Manuscript to JAS
Use our Editorial System to submit your paper
JAS Current Articles
Current Issues