Biocontrol Efficacy of Entomopathogenic Fungi against San Jose Scale Quadraspidiotus perniciosus (Comstock) (Hemiptera: Diaspididae) in Field Trials

Abstract

San Jose scale Quadraspidiotus perniciosus is a key pest of apple crop in the northern states of India. The efficacy of entomopathogenic fungi - Beauveria bassiana, Metarhizium anisopliae sensu lato and Lecanicillium lecanii against San Jose scale was examined in three apple orchards, each located at Srinagar, Bandipora and Pulwama districts in Kashmir. The relative pathogenicity of these fungi against the pest was also evaluated during field trials. Mortality was monitored at 2-day intervals until 30 days after application. All three fungal pathogens caused mortality of the pest particularly with the increase in treatment concentration. High mortality (76-77%) was determined with B. bassiana at 15 í— 10⁵ conidia/ml. formulation followed by L. lecanii at the same formulation (mortality 73-75%) at all the experimental sites tested. M. anisopliae sensu lato was significantly less effective (mortality 47-67%) in all the three field trials. The results demonstrate the suitability of entomopathogenic fungi for controlling San Jose scale.