In-vitro compatibility of entomopathogenic fungus, Lecanicillium lecanii (Zimm.) Zare and Gams with insecticides and fungicides

Abstract

The compatibility of Lecanicillium lecanii with insecticides and fungicides was tested to identify and incorporate the compatible chemicals in the IPM package for sucking pest management. Among the new generation insecticides tested, we found flubendiamide 39.35% SC, chlorantraniliprole 18.5% SC, imidacloprid 17.8% SL and thiamethoxam 25% WG were found to be compatible with L. lecanii at all the three doses. Thiamethoxam, 25 % WG, was the least inhibitive at recommended dose with the highest Biological index (BI) of 80. Of the old-generation insecticides, dimethoate 30 % EC was compatible, while malathion 50 % EC, quinalphos 25% EC and chlorpyrifos 20% EC were toxic to L. lecanii. Quinalphos, 25 % EC, was the highly inhibitive insecticide with a BI of 14-18, exhibiting
a significant reduction in growth, sporulation, and germination of the fungus. Among the fungicides tested, copper oxychloride 50% WP and azoxystrobin 23% SC were moderately toxic. Other fungicide viz., tebuconazole 25% EC, hexaconazole 5% EC, carbendazim 50% WP and mancozeb 75% WP were found to be toxic to L. lecanii.