In vitro Interactions of Bacillus thuringiensis with Biorationals and Synthetic Insecticides

Managing crop pests using microorganism is one of the key component and eco-friendly alternative to reduce chemical inputs in integrated farming systems. Biorationals and chemical pesticides can exert either antagonistic or synergistic effects on the efficacy of entomopathogens potentially impacting natural epizootic outbreaks. The present study was therefore undertaken to evaluate the in vitro compatibility between Bacillus thuringiensis with biorationals and synthetic insecticides. The findings revealed that B. thuringiensis MTCC 9025 recorded minimum growth percent reduction over control with Beauveria bassiana PCP-6 (5.33%) and B. bassiana MTCC 6097 (12.76%) and were highly compatible. However, B. thuringiensis MTCC 8481 recorded maximum growth percent reduction and was least compatible. All B. thuringiensis isolates were compatible with azadirachtin 5% w/w (@0.2ml/l and @0.4ml/l) and synthetic insecticide Chlorantraniliprole 18.5% SC (@0.2ml/l and @0.4ml/l). However, all B. thuringiensis isolates were incompatible with Emamectin benzoate 5% SG and exhibited maximum growth percent reduction over control. The results indicated that B. thuringiensis isolates could be successfully integrated into Integrated Pest Management strategies with Beauveria bassiana isolates, azadirachtin 5 % w/w and chlorantraniliprole 18.5% SC.