EFFICACY OF COMMERCIAL INSECTICIDE FOR THE MANAGEMENT OF COWPEA POD BORER (MARUCA VITRATA) ON COWPEA (VIGNA UNGUICULATA (L.) WALP) UNDER FIELD CONDITION IN CHITWAN, NEPAL

A field experiment was conducted to evaluate the efficacy of commercially available insecticides for management of cowpea pod borer to know about the effective and safe chemical insecticide to manage the cow pea pod borer. A total of five treatments; (i. Neemix (2ml/L), ii. Flubendamide 48% SC (2ml/L), iii. Spinosad 45% SC (3ml/L), iv. Chlorantraniliprole 18.5% SC(2ml/L) and v. control) were tested using Randomized Complete Block Design (RCBD) with four replications for each treatment. The results showed that the Chlorantraniliprole 18.5% SC was most effective to reduce cowpea pod borer larva followed by Flubendamide 48% SC and Spinosad 45% SC. The damage of pod by cowpea pod borer was recorded the highest control plot (20.53%) whereas lowest fruit damage was recorded Chlorantraniliprole (5.18%) followed by Flubendamide (5.44%). Among the treatments, the highest yield was obtained with Chlorantraniliprole (11.22mt/ha) followed by Flubendamide (9.21mt/ha) and Spinosad (8.27/ha). Whereas the lowest yield was obtained with control plot (6.59mt/ha) followed by Neemix (7.09mt/ha) treated plots. The benefit-cost (B:C) ratio for all the treatments revealed that chlorantraniliprole @ 0.2ml/L was highly economical with a B:C of 1:62.14 followed by spinosad with 1: 21.91. The chlorantraniliprole resulted the lowest larval count, lowest fruit damage, highest yield and highest marginal B: C thus could be the best insecticide to manage cowpea pod borer.