Recycling of wastes obtained particularly from semi-synthetic diet during mass production of nuclear polyhedrosis virus of Helicoverpa armigera (Hubner) in biocontrol laboratory for biogas production and cultivation of mushroom, Pleurotus sajor-caju (Fr.) Singer

The semi-synthetic diet, obtained as waste during mass culturing of larvae of Hellcoverpa armigera (Hubner), was used for biogas production as also for the cultivation of edible oyster mushroom. The utilization of waste semi-synthetic diet (WSSD) and its combination with cowdung (1:1, 1:3, 3:1) and dried banana leaves in the laboratory revealed that cowdung alone (300 g) produced the maximum quantity of total gas (22,486.8 ml) over 13 weeks, followed by WSSD + cowdung (1: 1) (22,032.3 ml). Gas produced by WSSD alone contained the maximum methane content (56.5%). Similarly, in spawn production of oyster mushroom, Pleurotus sajor-caju (Fr.) Singer, WSSD could be used and the sorghum grains (substrate for mycelial growth) were replaced by 6.67%, WSSD. This suggests that not only the cost of rearing will be reduced but will also provide the solution for the problem of waste disposal.