Somatic-gametic tradeoffs in two Trichogramma species: Influence of host size and Wolbachia infection as affected by host availability.

摘要

A series of experiments were conducted to determine whether Trichogramma platneri Nagarkatti and T. kaykai Pinto and Stouthamer (Hymenoptera: Trichogrammatidae) manifested a somatic-gametic trade-off. With T. platneri, the experiments tested whether host availability influences the trade-off. With T. kaykai, the experiments tested whether the parthenogenetic-inducing bacteria, Wolibachia affected the trade-off. In T. platneri, limiting the number of available hosts daily to large wasps or depriving them of hosts for up to 10 days did not significantly affect their progeny production. In contrast, depriving small T. platneri of hosts for one and three days significantly reduced their progeny production. Large T. platneri produced more offspring and lived longer than small wasps independent of the host species on which they were reared.; With T. kaykai, Wolbachia-infected females parasitized fewer hosts, produced less progeny, produced fewer daughters, and lived for a shorter period than their uninfected counterparts. Uninfected T. kaykai developed faster at higher temperatures (20, 25, and 30°C), Whereas infected females developed faster at the lowest temperature (15°C). Behavioral observations showed that field-collected, Wolbachia-infected and uninfected T. kaykai had similar oviposition behaviors. These showed that Wolbachia-infected T. kaykai rejected more previously parasitized hosts, suffered greater intrinsic mortality during development, allocated a smaller clutch size to previously parasitized hosts, and suffered greater interbrood mortality in hosts superparasitized by both Wolbachia-infected and uninfected wasps than their uninfected counterparts.