Comparative efficacy of microbials and botanicals against diamondback moth (Plutella xylostella Linn) on cabbage

The present investigation was conducted during rabi season of 2019-2020 at SHUATS, Prayagraj in randomized block design on three replications. Eight treatments comprised of botanicals viz. Neem seed kernel extract 5%, Neem leaf extract, Neem oil 10ml/lit and three treatments of Microbials i.e., Beauveria bassiana 3g/lit of water, Bacillus thuringiensis 1g/liter of water and Spinosad 45SC 0.32ml/lit, Indoxacarb 14.5SC 0.35ml/lit and one untreated control was taken. The observations on larval population 3,7 and 14 days at each spraying (1st and 2nd) were recorded for computing the percent larval reduction. The data revealed that highest percentage reduction of DBM larvae was observed in Spinosad 45SC (84.97%) followed by Indoxacarb 14.5SC (58.77%) and Bacillus thuringiensis (46.62%). The mean crop yield ranged between 298 q/ha to 228 q/ha in the insecticidal treatments, the highest yield was recorded in Spinosad 45SC (298 q/ha) followed by Indoxacarb 14.5SC (275 q/ha) and Bacillus thuringiensis (268 q/ha). The cost benefit ratio varied from (1:5.97) to (1:5.57) in different treatments, the highest was recorded in Indoxacarb14.5SC (1:5.97) followed by Bacillus thuringiensis (1:5.94) and Spinosad 14.5SC (1:5.86).