Evaluating in vitro Compatibility of Pesticides with Metarhizium anisopliae (Metchnikoff) Sorokin and Its Pathogenicity against Aphis craccivora Koch

Abstract

An in vitro trial was conducted in the Department of Entomology, Dr. Balasaheb Sawant Konkan Krishi Vidyapeeth, Dapoli, Ratnagiri, Maharashtra; to determine the compatibility of green muscardine fungus, Metarhizium anisopliae (Metachnikoff) Sorokin with pesticides and its pathogenicity against A. craccivora. Azadirachtin, Buprofezin and Sulphur were the most suitable pesticides as it showed significantly superior growth on potato dextrose agar media over untreated control. However, Emamectin benzoate, Azadirachtin, Profenophos, Indoxacarb, Thiophanate, Paraquat Dichloride and Glyphosate showed significantly higher mean mycelial weight over the untreated control on potato broth medium. At the same time, amongst pesticides used in the experiment; only insecticides (Emamectin benzoate, Azadirachtin and Deltamethrin) reported synergistic increase in conidial count with the untreated control, while fungicides and herbicides reported drastic reduction in conidial count. The pathogenicity of M. anisopliae harvested from the pesticide treatments against A. craccivora revealed that all the pesticides investigated had reduced its pathogenicity in comparison to untreated control. However Emamectin benzoate, Indoxacarb and Paraquat dichloride showed maximum per cent mortality and can be used in combination with M. anisopliae.