Efficacy of nucleopolyhedrovirus against Spilarctia obliqua (Walker) on mulberry

Pot experiments carried out to study the efficacy of nucleopolyhedrovirus against the Bihar hairy caterpillar Spilarctia obliqua (Walker), at Bangalore indicated that a spray of NPV @ 1×10⁷ POB ml⁻¹ resulted in a larval mortality of 93.33% in third instar larvae and 87.5% in fourth instar larvae. Cent per cent larval mortality was obtained when the plants were sprayed with dichlorvos @ 2 ml l⁻¹. The leaf damage for viral treatments varied from 19.65 to 41.89 and 21.0 to 38.0 per cent for third and fourth instar larvae, respectively.