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 3^rd, 4^th and 5^th 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 3^rd, 4^th and 5^th 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 3^rd instar larvae at a dose of 10 infective juveniles per larva.