ANTIFEEDANT EFFECT OF SYNTHETIC PYRETHROIDS TO THE LARVAE OF BIHAR HAIRY CATERPILLAR, SPILOSOMA OBLIQUA WALKER ON MUSTARD AND CASTOR PLANTS

In a laboratory trial synthetic pyrethroids cypermethrin, delta methrin and fenvalerate on mustard and castor plants (a) 0.05% a. i conc. spray showed antifeedant properties to the larvae of Spilsona obliqua Walker. The insect consumed a maximum of about 10 per cent area of the treated leaves in comparison to almost complete consumption of leaves sprayed with endosulfan, monocrotophos, acephate, methyl parathion, diazinon and triazophos insecticide at the same level of application. Insect mortality occured between 40 to 100% on castor and between 16.67 to 50% on mustard plants possibly due to starvation. Thus these synthetic pyrethroid insecticides could be employed successfully as antfeedants in controlling Bilar hairy catepillar on mustard and castor.