Bioefficacy of entomopathogenic mycoformulations and effect of adjuvants against nymphs of cabbage aphid, Brevicornye brassicae (Linnaeus)

Abstract

Cabbage aphid, Brevicornye brassicae (Linnaeus) is one of the major insect pests of cabbage. Chemical control is mostly used to manage this pest. The present investigation was conducted to evaluate an environmentally benign approach for the pest management through different entomopathogenic mycoformulations against nymphs of B. brassicae to identify effective mycoformulation. The effect of mycoformulations supplemented with different adjuvants against nymphs of B. Brassicae was also evaluated under laboratory conditions. The bioassay studies of fungal bioformulation against nymphs of B. brassicae recorded maximum cumulative per cent mortality (53.33%) in talc formulation of L. lecanii MTCC 956 and commercial L. Lecanii formulation @12g L^-1 and these were at par with each other. Maximum percent reduction of nymphal population over control 54.66 and 51.33 per cent was recorded @12 g L^-1in talc formulation of L. lecanii (MTCC 956) and commercial L. Lecanii formulation ten days after treatment respectively. Laboratory studies undertaken to evaluate talc formulation of L. lecanii MTCC 956 lecanii with and without adjuvants against the nymphs of B. brassicae recorded maximum percent increase in mortality over control (7.89%) in L. lecanii formulation + tween80@1%. Results of this study signified that L. lecanii formulation, when supplemented with adjuvants enhanced the growth of L. lecanii and increased mortality of nymphs of B. brassicae and could be used as a part of the integrated pest management program.