Bioefficacy of Steinernema masoodi (Ali et al., 2005) Against Pre Pupa/Pupa of Helicoverpa armigera

A dose of 200–500 IJs of S. masoodi in 100 g of soil was sufficient to bring down the mortality of soil dwelling stage (pupa) of H. armigera and curb the adult emergence from pupa. At this dose the adult emergence was only 15–25% as compared to 95% in control. Under field condition, a dose of 6x10⁹ IJs of S. masoodi/plot of 50 X 50 cm when applied to soil, 12% adult emergence was observed against 92% in control thus indicating that EPN can effectively kill the soil dwelling stage (pupa) of the insect. Infection of pre pupa/pupa of H. armigera through S. masoodi has been reported for the first time. This finding can be made use in IPM of H. armigera to combat this pest even in the soil especially where number of generations are recorded in a single crop season.