Hybridization in principal parasitoids of synanthropic Diptera: the genus Muscidifurax (Hymenoptera: Pteromalidae)

Abstract

Parasitoid vigor measured by female longevity, progeny production, and host destruction, is compared among cohorts from different populations of Muscidifurax raptor, M. zaraptor, M. raptorellus and M. uniraptor, parasitoids of synanthropic flies. Hybridization between populations usually produced an immediate post-mating parasitization depression in the female, with partial or full recovery occurring in randomly mated F1 or F2 progeny. Parasitization intensity approached an asymptote when females were 6 to 7 d old. Single matings were sufficient to guarantee female-biased sex ratios in progeny through 10 oviposition d, after which senescing females fertilized fewer eggs. Virgin females either approximated or exceeded mated females in parasitization activity. Preintroduction assessments of different parasitoid populations may be desirable for biological control to avoid postmating depression and the creation of inferior hybrids. -from Author