Fungi related to larvae of red palm weevil Rhynchophorous ferrugineus (Coleoptera: Curculionidae)

Abstract

As a first step to developing effective biocontrol strategies, we analyzed the pathogens and mainly the entomopathogenic fungal species, present into dead larvae of Rhynchophorous ferrugineus; a quarantine pest recently introduced and acclimated in Sicily (Italy). From 2008 to 2010, we estimated the natural larval mortality (> second instar) of R. ferrugineus collected from infested palm Phoenix canariensis; that was variable from 10 to 35%, according to the different seasons Among the different pathogens recorded the fungi seems have an important role, than in order to distinguish saprophytic or opportunistic species from potential pathogens (including the non cultivable ones) we applied different protocols based on observation by optical and scanning electron microscopy and on molecular analysis. Among fungi species, Acremonium and Beauveria were identified as agents of eumycotic white grain mycetoma, found into several dead larvae. Both of them are considered for biological control and Acremonium is reported to be endophytic with a potential role in the reducing population of phytophagous. The identified species should be play a potential role in controlling R. ferrugineus population in Sicily