Trehalose and Other Carbohydrates in Diapausing and Starving Boll Weevils1,2

Abstract

Anthonomus grandis Boheman (Coleoptera: Curculionidae) was studied to determine the effects of diapause and starvation on trehalose and glycogen levels. When corrections were made for the greater dry weight of diapausing boll weevils, there was little if any difference in trehalose levels between diapausing and reproducing adults and between males and females. The effects of starvation also were small because trehalose levels in weevils starved for 12–20 hours were about normal. Glycogen may have been metabolized at a more rapid rate in starved reproducing than in starved diapausing weevils. But trehalose levels were maintained in weevils starved 12–20 hours because the trehalose content of reproducing weevils was equal to or slightly higher than that of diapausing weevils. On a dry-weight basis, glycogen levels in weevils fed bolls continually were greater in reproducing than in diapausing individuals. Because levels of glycogen and trehalose were no greater in diapausing than in reproducing weevils, the increased longevity of overwintering diapausing weevils cannot be caused by accumulations of glycogen or trehalose.