Control of Earias vittella (Lepidoptera: Noctuidae) by Beauveria bassiana along with Bacillus thuringiensis

A laboratory strain of Beauveria bassiana sensu lato (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) and commercial formulation of Bacillus thuringiensis (Berliner) were assessed against three field populations of Earias vittella F. (Lepidoptera: Noctuidae) in the laboratory. Three dose rates of B. bassiana (1.5x10(6), 1.5x10(7) and 1.5x10(8) conidia mL(-1)) and one of B. thuringiensis (0.5 mu g g(-1)) were applied alone and in combination against 2nd and 4th larval instars. The mortality was observed until pupation. The bioassays were carried out at 25 degrees C and 75% RH The highest larval mortality was observed in the population from Faisalabad with lowest pupation rate, adult emergence and egg eclosion treated with combined concentrations of B. bassiana and B. thuringiensis. The lowest mortality was observed in population from Pakpattan among all the tested populations. Overall results demonstrated that all the treatments gave significant control of E. vittella and both microbial agents may become the integral part of the successful IPM program of E. vittella in okra crop. (C) 2015 Friends Science Publishers