Virulence of entomopathogenic fungi to cashew stem and root borer, Plocaederus ferrugineus Linnaeus (Coleoptera: Cerambycidae) under laboratory conditions

摘要

The relative susceptibility of different life stages viz, egg, larvae and pupae of the cashew stem and root borer; Plocaederus ferrugineus Linnaeus (Coleoptera: Cerambycidae) to three entomopathogenic fungi (Beauveria bassiana (Balsamo) Vuillemin, Beauveria brongniartii (Sacc.) Patch (Hyphomycetes: Moniliales) and Metarhizium anisopliae (Metsch.) Sorokin (Deuteromycotina: Moniliales) was evaluated in laboratory by topical application of conidial suspension of 10~7 conidia/ ml. Of them, M. anisopliaewas found to be more effective with 36.0, and .33.3 per cent egg and larval mortality followed by B. bassiana with 30.0 and 30.9 per cent egg and larval mortality, respectively. Pupal mortality was 10.00 and 8.00 per cent with B. bassiana and M, anisopliae. There was moderate increase in terms of larval mortality due to fungal pathogens with a decrease in larval age.