DEVELOPMENT OF EFFECTIVE MANAGEMENT PRACTICES AGAINST POD BORER (Helicoverpa armigera Hubner) IN CHICKPEA

Abstract

The study was conducted to develop effective management practices against chickpea pod borer in the research field of Plant Pathology and Seed Science Department, Faculty of Agriculture, Sylhet Agricultural University (SAU), Sylhet from 25 November, 2014 to15 April, 2015. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. There were seven treatments including synthetic insecticides and botanicals. The treatments were lamda-chyhalothrin (Karate 2.5EC) applied @ 1.5 ml/L of water (T1), chloropyriphos + cypermethrin (Nitro 505EC) applied @ 2 ml/L of water (T2), chlorantranilprole + thiamethoxam (Virtako 40WG) applied @ 0.15g/L of water (T3), neem leaf extract (1:4) (T4), biskatali leaf extract (1:4) (T5), marigold leaf extract (1:4) (T6) and control (untreated) (T7). The 1st spray was applied at 50% of flowering stage, 2nd and 3rd sprays were applied at 10-day intervals after the 1st spray. Data on pod damage (%), reduction of pod damage over control (%) and seed yield (t ha-1) was recorded and analyzed statistically. Significant variations in pod damage and seed yield were observed among different treatments. The highest pod damage reduction (72.53%) over control was found from the plots treated with lamdachyhalothrin. The highest seed yield (1.6 t ha-1) and highest Marginal Benefit Cost Ratio (MBCR) (4.60) was also obtained from the same plots treated with lamda-chyhalothrin (T1). The 2nd highest MBCR (3.77) was found from the plots that were treated with neem leaf extract (T4). The results indicate that the use of lamda-chyhalothrin @ 1.5 ml/L of water is biologically effective and economically viable followed by neem leaf extract for the management of chickpea pod borer.