Veränderungen der Wirtsqualität von Lymantria dispar Larven für die endoparasitische Entwicklung der Braconidae Glyptapanteles liparidis durch eine Mikrosporidieninfektion

Changes in host suitability of Lymantria dispar larvae for the endoparasite development of the braconid Glyptapanteles liparidis by a microsporidian infection

Müncheberg

2001

S. 437-440

Bandaufführung

11826S

189235

We investigated interactions between the endoparasitoid G. liparidis (Hym., Braconidae) and the pathogen Vairimorpha sp. (Microsporidae, Burenellidae) within their host the L. dispar larva (Lep., Lymantriidae). Although the parasitoid did not become infected by Vairimorpha negative effects of the microsporidiosis of the host were ascertained. Parasitoids developing in infected hosts had a longer endoparasitic development, higher mortality during metamorphosis and resulted in smaller adults. We analysed free amino acids and carbohydrates in infected L. dispar hosts to find indications of a reduced suitability for G. liparidis development. The concentrations of several free amino acids were altered, e.g. levels of glutamine were reduced, levels of proline were increased in the hemolymph of infected larvae. The hemolymph of infected larvae was totally depleted from trehalose at the time when proliferation and spore formation in the host fat body began. Also glycogen content in the tissue was significantly reduced when the fat body had become completely invaded by the microsporidium.