Abstract
Differences in host-plant species may affect the structure of parasitoid communities of phytophagous insects. Phytophagous insect species often consist of host races, and comparisons between host races enable us to infer the effects of host-plant differences on parasitoid communities. Here, we compare the parasitoid fauna of two host races of the leaf-mining moth Acrocercops transecta, which are associated with either Juglandaceae or Lyonia ovalifolia (Ericaceae). Field collection and subsequent laboratory rearing revealed a significantly higher parasitization ratio in the Juglandaceae race than in the Lyonia race. In the Juglandaceae race the majority of parasitoids were Braconidae, whereas in the Lyonia race the majority were Eulophidae. Furthermore, even within the same host race the most abundant parasitoid species differed between populations with different host associations. Hence, the present results strongly indicate that different host-plant taxa affect the structure of parasitoid communities even within a single phytophagous insect species.
Acknowledgements
We thank K. Maeto, K. Takasuka and T. Yoshida for identification of parasitoid wasps, K. Mizota for his assistance in field collection of A. transecta mines and D. Hembry for comments on the manuscript and for English editing. We also thank anonymous referees for their comments on the draft manuscript. This work was supported by Research Fellowships of the Japan Society for the Promotion of Science (JSPS) for Young Scientists (20–5555) and JSPS KAKENHI grant number 23870037 to I.O.