Mating-induced inhibition of remating in female Mediterranean fruit flies Ceratitis capitata

Mechanisms producing inhibition of remating in mated female Mediterranean f ruit flies Ceratitis capitata, were investigated by matings with surgically altered males. Comparison of remating by females mated with either intact control males or males with a shortened penis, showed that ejaculate or a p hysical stimulus of penis insertion caused remating inhibition for at least 10 days after first mating. Remating frequency at two days after mating wa s significantly higher in females mated to castrated (spermless) males than in females mated to sham-operated control males. This difference disappear ed by day four after mating, indicating that sperm cause a shorter-term inh ibition of remating than does a normal first mating. Other factors in addit ion to sperm must therefore play a role in inhibition of remating. (C) 1999 Elsevier Science Ltd. All rights reserved.