BIOTOXICITY ASSAY OF NEEM (Azadirachta indica) PRODUCTS AND DISTILLERY EFFLUENT ON THE THIRD INSTAR LARVAE OF COCONUT RHINOCEROS BEETLE Oryctes rhinoceros

Abstract

The coconut Rhinoceros beetle (Oryctes rhinoceros) is one of the most damaging insect to coconut palms in India. The experimental study on the growth response of 3^rd instar larvae of Oryctes rhinoceros infesting the coconut trees.  The LC₅₀/96 hours value for the larvae of Oryctes rhinoceros were 29.5% for neem cake powder, 24.5% for neem oil and 14.9% for distillery effluent respectively.   In the present study, it was observed that the entire larval growth was affected with this bio-pesticides and distillery effluent irrespective of its experimental concentrations. The reduced weight of the larval forms exposed to different concentrations of bio-pesticides and distillery effluent were clear indication of their deterrent activity and they totally affect the larval growth, since no one was undergone pupation. Even mortality occurred at the midst of this experimental duration in higher concentration.  The overall data indicated that the distillery effluent caused antifeedent activity ultimately leading to deterrant activity, of larval forms.