Seminal fluids mediate sexual inhibition and short copula duration in mated female Queensland fruit flies

• Published in: Journal of insect physiology Vol. 53; no. 7; pp. 741 - 745
• Main Authors: Radhakrishnan, Preethi, Taylor, Phillip W.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.07.2007
• Subjects: accessory sex glands; animal tissue extracts; Animals; Bactrocera tryoni; Copula duration; Copulation; dose response; duration; Ejaculation; Female; female receptivity; fruit flies; Male; male reproductive system; mating behavior; mating frequency; Pupa - physiology; Remating inhibition; Semen - physiology; Seminal fluid; sexual behavior; Sexual Behavior, Animal - physiology; sexual receptivity; Tephritidae; Tephritidae - growth & development; Tephritidae - physiology; virgin females; Copula duration; Seminal fluid; Tephritidae; Remating inhibition
• ISSN: 0022-1910; 1879-1611
• DOI: 10.1016/j.jinsphys.2006.10.009

Molecules in male seminal fluid transferred to female insects during mating can have potent effects on their subsequent sexual and reproductive behaviour. Like many other tephritids, female Queensland fruit flies ( Bactrocera tryoni) typically have diminished sexual receptivity after their first mating. Also, copulations of females that do remate tend to be shorter than those of virgins. We here find that virgin females injected with small doses (0.1, 0.2 or 0.5 male equivalents) of extracts from the male reproductive tract accessory tissues, which consist of male accessory glands, ejaculatory apodeme and ejaculatory duct (AG/EA/ED), have diminished receptivity and short copula duration very similar to naturally mated females. In contrast, virgin females injected with saline or with high doses of AG/EA/ED (1 or 2 male equivalents) that likely exceed the range of natural variation retain the higher levels of sexual receptivity and longer copulations of un-injected virgins. We conclude that reduced sexual receptivity and shorter copulations of mated female Q-flies are mediated by products in the male seminal fluid derived from the male reproductive tract accessory tissues.