Pathogenicity and in vivo culturing of a local isolate of Steinernema carpocapsae against Spodoptera litura (Fab.)

Experiments were conducted in the laboratory to find out the pathogenicity of local isolate of Steinernema carpocapsae against 3rd, 4th and 5th instar larvae of tobacco caterpillar, Spodoptera litura (Fab.). Study revealed cent per cent mortality after 96 hours in all the tested larval instars and at all the doses. The LC50 values varied between 11.41 and 27.17 infective juveniles per larva in all the instars. The LT50 values of 3rd, 4th and 5th instar larva of S. lilura were observed to be 24.8, 31.5 and 38.8 hours, respectively. Fifth instar larvae of S. litura at a dose of 160 infective juveniles per larva produced maximum infective juveniles (3.29 × 105) whereas minimum number of infective juveniles (0.97 × 105) was obtained from 3rd instar larvae at a dose of 10 infective juveniles per larva.