author(s)
Priyadharshini Pachiappan, Prabhu S and Mahalingam CA

abstract
Leaf webber, Diaphania pulverulentalis (Hampson) (Lepidoptera : Pyralidae) is a key pest of mulberry. Use of chemicals to control the pests, developed resistance and destroyed beneficial insects. Nuclear Polyhedrosis Virus plays an vital role in management of leaf webber due to its restricted host specificity. In the present study, histopathology of NPV infected leaf webber larvae was carried out to know the mechanism underlying behind the extent of infection by Nuclear Polyhedrosis Virus. The feral dead larvae collected from the mulberry field, were examined under the microscope for the presence of virions and the polyhedral bodies were isolated, purified and maintained under lab conditions. The production of virus was performed in healthy third instar larvae of D. Pulverulentalis through leaf contamination method and histopathology was done on the NPV infected fifth instar larvae. The results showed that the virions were scattered throughout the granular virogenic stroma and accumulated peripherally with the advancement of infection. The midgut region of uninfected larvae of D. pulverulentalis did not show any evidence of damage or disruption of cells. Hence, it is proved that DpNPV could be an excellent potential and safe biopesticide for the management of leaf webber in mulberry eco system.