Safety Studies of DpNPV (Diaphania pulverulentalis Nuclearpolyhedrosis Virus) Suspension and its Formulation on Non-Target Organisms in Mulberry Ecosystem

Regular usage of toxic chemicals in mulberry garden to control the pests cause pollution and are detrimental to human beings and beneficial organisms including silkworms. Further, the pests develop resistance to the chemical insecticides with indiscriminate use and result in sudden outbreak. In view of these, pest management using non-chemical methods have gained importance including biological control. Among bio control agents, baculovirus are very important as they are arthropod specific pathogens. Higher host specificity and amenability for formulation as that of chemical pesticides make baculoviruses particularly attractive as biological control agents (Dent and Jenkins, 2000). The Baculoviridae is a promising family of viruses that might provide active Laboratory studies were carried out to explore the potential of Diaphania pulverulentalis (Hampson.) nucleopolyhedrosis virus (DpNPV) suspension and its formulations against non-target organisms viz., Trichogramma chilonis Ishii, Chrysoper lacarnea (Stephens), Bombyx mori (L.), Apiscerena indica (Fab.), Apis mellifera (L.) and Apis florea. The per cent parasitization, adult emergence of T. chilonis exposed to DpNPV suspension did not differ significantly with that of DpNPV formulations and control, while, the per cent parasitization and adult emergence were significantly lower in dichlorvos treated eggs. C. carnea exposed to DpNPV suspension showed no adverse effects on per cent hatchability, larval period, per cent pupation, pupal period, adult emergence, adult longevity, total life cycle and grub mortality in comparison with DpNPV formulations and control. Whereas, dichlorvos was found to be hazardous compared to NPV and control. The larval weight of third, fourth and fifth instar of B. mori, per cent larval mortality, pupation, pupal period, adult emergence cocoon weight and shell weight exhibited no significant differences between the virus treated and control indicating the safety of the DpNPV suspension and its formulation. The survival period of bees in virus treatments was on par with control, while the survival period of bees was significantly low (1-2 days only) in dichlorvos. Results indicated no evidence of infection or other pathological manifestations in the tissues of bees. K e y w o r d s