Effect of a low cost diet on the cotton leaf worm, Spodoptera littoralis nucleopolyhedrosis virus pathogenicity and sterile insect technique

Mass rearing cost of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae) is one of the critical methods for the successful utilization of Baculovirus pathogenicity and sterile insect technique (SIT). Effectiveness of both SIT and S. littoralis Nucleopolyhedrosis Virus (SpliNPV) was assessed in response to plant-based diet and substitution of agar with commercial sources of gelling components as feed. Pupal and adult recoveries produced by castor bean leaves were significantly high, followed by the agar-based diet. Moreover, larval durations were significantly prolonged for (starch + gelatin)-based diet than the other dietary diets. Obviously, SpliNPV pathogenicity against the larvae reared on (starch + gelatin)-based diet was 2.5 and 2 times higher than those reared on castor leaves and agar-based diet, respectively. Contrary to expectation, the sterility doses of male moths produced by castor leaves and agar-based diet were relatively similar. The findings suggest that the lowest cost diets (starch + gelatin)-based diet could be used effectively for increasing the SpliNPV pathogenicity, while either castor leaves or agar-based diet could be considered as a promising choice for SIT program.