Avoidance of parasitized host by female wasps of Aphidius gifuensis (Hymenoptera: Braconidae): The role of natal rearing effects and host availability?

In this study we examined whether and how parasitoids ’ natal rearing experience would affect their host discrimination ability according to host availability. We established separate colonies ofAphidius gifuensis Ashmead by continual rearing on two hosts,Sitobion avenae F. andMyzus persicae (Suzler), and quantified self superparasitism and self superparasitism versus parasitism ratio for the four combinations of parasitoid colonies and host species (S. aveane andM. persicae) at four host densities (30, 50, 100 or 150 per plant). Results showed that self superparasitism ofM. persicae byA. gifuensis reared onS. avenae was significantly higher than by those reared onM. persicae, no matter whether the host densities were 30, 50, 100 or 150.Aphidius gifuensis reared onM. persicae significantly superparasitized moreS. avenae than those reared onS. aveane only when host density was 30. Self superparasitism versus parasitism ratio ofA. gifuensis from both colonies was always lower on natal hosts than on new hosts, and the difference was more pronounced as the host density decreased. These results suggested that natal rearing effects is important on host discrimination and oviposition decision of the parasitoidA. gifuensis. These effects promoted the parasitoid's host adaptation and made them confer greater fitness.

Source: Insect Science - November 22, 2018 Category: Biology Authors: Ming ‐Zhen Pan, Tong‐Xian Liu, Christian Nansen Tags: ORIGINAL ARTICLE Source Type: research