Evaluation of Oil Based Formulation of Beauveria bassiana (Bb 112) (Bals.) Vuill. and Delivery Methods for the Management of Chilli Thrips, Scirtothrips dorsalis Hood

In recent years, increased interest has been shown towards biological control based management practices following the unsatisfactory results with the application of conventional insecticides. In Integrated Pest Management, selection of right plant protection methods coupled with right appliance is important to tackle the target pest in an effective manner. In this context, microplot and field trials were carried out to evaluate the efficacy of the oil based formulation of B. bassiana (Bb 112) against chilli thrips, Scirtothrips dorsalis Hood to identify an effective delivery method among different sprayers used (ASPEE Maruyama Engine sprayer, Avenger ULV sprayer, ASPEE Battery sprayer, ASPEE Knapsack hand sprayer, ASPEE Hitech hand sprayer and CDA sprayer). Microplot experiment on chilli thrips, S. dorsalis revealed that the oil based formulation of B. bassiana (Bb 112) was significantly superior to all other treatments and recorded the highest cumulative mean population reduction of 47.54 per cent. The cumulative mean per cent reduction in first (at Kumarapalayam) and second field trial (at Ambilikkai) against Chilli thrips showed that, oil based formulation of B. bassiana (Bb 112) @ 10⁸ spores ml^-1 sprayed with CDA sprayer was significantly superior to other treatments with 43.01 and 46.65 per cent reduction, respectively.