Nutritional contribution to females of¹⁴C-labeled male secretions transferred during mating inMenida scotti (Heteroptera: Pentatomidae)

Abstract

Menida scotti (Puton) males have been shown to transfer secretions from their bulbus ejaculatorius and reservoir of ectodermal accessory gland to females by mating during hibernation. In the present study, the major components of the secretions were found to be proteins and lipids. To specify the female organ incorporating the male secretions, a radiotracer experiment in which the male secretions were labeled by [¹⁴C]valine was conducted in nine tissues of females collected in the fall and spring of the hibernation period. Relatively high radioactivities were detected in the haemolymph and the residual carcass (head, legs, air-sacs, exoskeleton, etc.) in the fall females, and in CO₂ gas evolved and carcasses in the spring females. The radioactivities in the fat body were significantly higher in the fall mating females than in the spring mating females, and vice versa in the ovary. The radioactivities in six fractions (lipids, proteins, glycogen, sugars, free amino acids and the residues) were also assayed in the five organs of females that had a relatively high radioactivity. The highest radioactivity was detected in the protein fraction of the haemolymph in fall and spring females. There were significant differences in the radioactivities incorporated into the lipid fractions of the carcass between fall and spring females.