DETERMINATION OF THE EFFECTIVENESS OF DIFFERENT DOSES OF NEEM PRODUCTS AND TWO BIO-CONTROL AGENTS FOR COMBATING CHICKPEA POD BORER Helicoverpa armigera (Hubner)

Abstract

A study was conducted at the Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka, Bangladesh during the period from November, 2009 to March, 2010 to evaluate the effectiveness of different doses of neem products and bio-control agents on the basis of infestation level of chickpea pod borer (Helicoverpa armigera) on chickpea pods, variety BARI Chola-5. The experiment comprised of 7 treatments as T1: Neem oil @ 3 ml/L of water at 7 days interval, T2: Neem oil @ 5 m1/L of water at 7 days interval, T3: Neem seed kernel @ 20 g/L of water at 7 interval, T4: Neem seed kernel @ 30 g/L of water at 7 interval, T5: Trichogramma evanescense @ 0.5 gm/6m2 at 7 days interval, T6: Bacillus thuringiensis serovar kurstaki @ 1.5 ml/L of water at 7 days interval and T7: Untreated control. The plants treated with T2 treatment resulted significantly lowest pod infestation compared to those of other treatments during early, mid and late fruiting stage. Significantly the highest yield was also obtained from the treatment T2. The treatments T4 and T1 also yielded more or less similar result as in treatment T2. The yield contributing characters were found highest in T2 treatment for longest plant, branches plant-1, leaves plant-1, pods plant-1, pod length and number of seeds pod-1. The highest BCR was found in the treatment T2 may be due to the minimum infestation and cost compared to the other treatment components and the highest yield was produced in this treatment. The percentage of infestation of chickpea pod gradually increased from early fruiting stage to late fruiting stage by number and weight. Therefore, any control measure taken from pod initiation to harvest might be effective for controlling pod borer of chickpea.