Distribution of late instar Lymantria dispar cadavers killed by Entomophaga maimaiga on trunks of several tree species in southwestern Japan

Abstract

Attachment of late-instar Lymantria dispar L. (Lepidoptera: Lymantriidae) cadavers killed by Entomophaga maimaiga Humber, Shimazu et Soper (Zygomycetes: Entomophthorales) on trunks of five dominant tree species was determined in a broadleaf forest in southwestern Japan. The highest numbers of cadavers were found attached to the trunk of Pasania glabra (Thunb.) Oerst., while there were moderate numbers of cadavers on the trunks of Quercus glauca Thunb. and Quercus serrata Thunb. and no cadavers were found attached to trunks of Ilex pedunculosa Miq. and Clethra barbinervis Sieb. et Zucc.. All examined cadavers contained E. maimaiga resting spores. The differences in cadaver attachment among tree species may influence density of E. maimaiga resting spores around tree bases, which act as reservoirs for fungal survival during unfavorable periods or over numerous years. Our results provide important information as to where to collect E. maimaiga resting spores for biological control of L. dispar, especially in forests containing many tree species.