Vitellogenesis in acanthoscelides obtectus coleoptera bruchidae 2. the conditions of vitellogenesis in a strain from colombia comparative study and adaptive significance

Huignard, J.; Biemont, J. C.

The reproductive activity of an A. obtectus strain originating in the high Colombian plateau (Altiplanos) was compared to that of a European strain. Colombian females exhibited greater individual variations than their European counterparts. Some females did not synthesize vitellogenin during the 140 days of observation, while others performed synthesis but not incorporation into oocytes. Under these conditions, 40-50% of the females could form a limited number of oocytes. The presence of Phaseolus vulgaris seeds stimulated vitellogenin synthesis and incorporation by most females. This initiation of ovarian activity enabled mating to occur, which in turn led to maximal stimulation of oogenesis. This host plant-mating interaction leads to the production and release of a large number of eggs. The observed variability of reproductive activity and its dependence on stimulatory factors probably reflect an adaptation to the ecological conditions prevailing in the high altitude environment of these insects.