Compatibility of Beauveria bassiana (Balsamo) Vuillemin, an entomopathogenic fungi, with selective insecticides for enhanced pest management

Abstract

Six insecticides, viz. Imidacloprid 17.8 SL, Chlorpyrifos 20 EC, Quinalphos 25 EC, Dimethoate 30 EC, Dichlorvos 76 EC and Fenvalerate 20 EC, at three concentrations [recommended dose - RD, and 0.5 per cent each below RD (BRD) and above RD (ARD)] were used to treat on the entomopathogenic fungus, Beauveria bassiana (Balsamo) Vuillemin. Impact on the conidial germination, vegetative growth, and spore production was studied by grading as harmless (<50%), slightly harmful (50-79%), moderately harmful (80-90%), and harmful (>90%). Among all these treatments, imidacloprid and fenvalerate were rated as harmless to B. bassiana, whereas chlorpyrifos, was slightly harmful in all three concentrations. In the case of treatment with dimethoate, the toxicity was slightly high in the RD and BRD but moderate at ARD. Quinalphos was moderately toxic in all three concentrations; however, dichlorvos was highly toxic, and there was no mycelial growth in all the three concentrations. Imidacloprid and fenvalerate are found highly compatable with B. bassiana.