Efficacy of the entomopathogenic fungus, Metarhizium anisoplae, against Khapra beetle Trogoderma granarium (Coleoptera: Dermestidae) under laboratory conditions

Abstract

The khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), is an important pest of stored wheat worldwide. This study assessed the efficacy of two isolates of M. anisoplae (commercial and local isolates). Different conidial concentrations (1×108, 1×106, 1×104) conidia/ml-1 and fungal filtrate (100, 75, 50) % of M. anisoplae were evaluated. In both fungal isolates, corrected mortality of T. granarium after exposure varied according to fungal concentrations conidial concentration of conidia/ml-1, and the fungal filtrate at a concentration of 75% caused the highest mortality rates. In addition, mortality rates were significantly varied according to the beetle's developmental stage. Both isolates of M. anisoplae caused between 41 and 67.6 % reduction in total fecundity of the female adults. The results demonstrate no significant differences between the local isolate of M. anisoplae and commercial formulation (Met 52 EC). Further studies under commercial storage conditions are required. Keywords: Insects storage pests, biological control, Entomopathogenic fungi