Efficacy of nuclear polyhedrosis virus and flubendiamide alone and in combination against spodoptera litura F.

Nuclear polyhedrosis virus (npv) is an important potential pathogen which can control a wide range of bollworm larvae in both agricultural and horticultural crpos. flubendiamide is a new chemistry insecticide which also controls bollworm effectively and relatively safer for natural enemies and beneficial arthropods. present investigations were carried out to determine their impact on larval mortality,pupal and adult emergence of 2nd and 4th instar larvae of spodoptera litura f. under laboratory conditions. both npv and flubendiamide were applied using diet incorporation method. larvae were allowed to feed for 48 h. mortality was recorded until larvae died or pupated. second instar larvae showed more susceptibility as compared with 4th instar larvae. maximum mortality was recorded in 2nd instar larvae (91.02±2.04%) in comparison to fourth instar larvae (69.35±1.66%) in combined application of npv and flubendiamide. dose of flubendamide was the key factor for type of interaction,its combination with npv at lower dose showed synergistic interaction (ctf=20). while rest of the combination showed additive effect (ctf=20). integration of npv and flubendiamide proved more fatal at higher concentrations than the individual application at lower concentration for pupation and adult emergence of s. litura. apart from untreated larvae (control) maximum pupation (66.01±1.32 and 73.95±1.28 %) and adult emergence (61.87±1.71 and 67.77±1.11 %) was observed when larvae were treated with npv (1x107 pob/ml) against 2nd and 4th instar larvae. this study would be helpful to use npv and flubendiamide in ipm under field conditions to control s. litura on cauliflower. copyright 2017 zoological society of pakistan.