DEVELOPMENT OF MANAGEMENT PRACTICES AGAINST JASSID (Amrasca devastans) IN OKRA

Abstract

The experiment was conducted at the field laboratory of Sher-e-Bangla Agricultural University, Dhaka during the period from November, 2013 to March, 2014 to find out the efficacy of different management practices against jassid in okra. The treatments comprised two botanical products, two synthetic chemical insecticides along with soap and detergent and one untreated control. These treatments are T1 = Spray with soap @ 3g/L of Water at 7 days interval; T2 = Spray with neem oil @ 4ml+Trix (detergent) @ 10 ml/L of water at 7 days interval; T3 = Spray with neem seed kernel water extract @ 20g/L of water at 7 days interval; T4 = Spray with (Fenitrothion) Sumithion 50EC@ 1ml/L of Water at 7 days interval; T5= Spray with Admire 200SL@ 0.5ml/L of water at the 7 days interval and T6= Untreated Control. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. The data were recorded on fruit infestation by number, weight and diameter of individual fruit at early, mid and late fruiting stages; and yield related attributes as well as yield of okra. Among six treatments, T5 treatment (Admire 200SL) reduced the highest percent (88.46 %) of fruit infestation by number and fruit infestation by weight (85.94 %), followed by T2 treatment (neem oil + trix) 77.73% and 75.39% respectively, whereas T1 treatment (soap water ) showed the least performance, 32.05% and 30.83% respectively by number and weight. Considering plant and yield related attributes, maximum height of plant (132.97), length of fruits (10.89), and diameter of fruits (1.188) were recorded in T5 treatment over control followed by T2. Similarly the highest fruit yield (23.39 ton/ha) was also achieved by the application of Admire 200SL with the increase of 60.21% yield over control whereas soap water showed least yield (15.89 ton/ha), followed by Sumithion 50EC (19.03). Okra yield increased due to increases of fruit length, diameter and plant height; on the other hand fruit yield decreased due to increase of fruit infestation by number and weight. The chemical insecticide Admire 200SL is the most effective in controlling jassid. Among other treatment Neem oil+ trix performed better to control jassid in okra. Considering Benefit Cost Ratio (BCR) and environment aspect, it may be suggested that neem oil+ trix, neem seed kernel water extract and use of soap water may be suitable option than other control.