author(s)
Dr. P Lakshmidevi, Dr. C Gopalakrishnan and R Selastin Antony

abstract
The plant oil based bio-formulation of Beauveria bassiana (B2 and TBb8) strains and its mixture amended with and without plant derived oils were developed and tested for their efficacy against the lepidopteran fruit borer insect pest (Helicoverpa armigera) in tomato under glasshouse and field conditions. Application of oil based bio-formulation of strains mixture (amended with or without oil) through seed, soil and foliar spray effectively reduced the incidence of fruit borer in tomato compared to individual control treatments both under glasshouse and field conditions. Tomato leaves when treated with this bioformulation mixture, altered the feeding behavior of fruit borer larvae and increased larval mortality under in vitro. Further, a significant increase in growth parameters and yield were observed in tomato plants treated with compared to untreated control. Increased accumulation of defence related enzyme was observed in tomato plants treated with against H. armigera when compared to other treatments.