USE OF PLANT MATERIALS FOR THE MANAGEMENT OF SUCKING INSECT PESTS OF OKRA

Abstract

The present experiment was conducted at the field laboratory of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka during the period from April to August, 2011 to find out the efficacy of different plant materials against sucking pest of okra. The treatments comprised seven botanical products, one synthetic chemical insecticide and one untreated control and these were T1 = Ripcord 10EC @ 1 ml/L of water, T2 = Tamarind fruit juice @ 100 g/4L of water, T3 = Neem leaf extract @ 0.5 kg/4L of water, T4 = Bullock’s heart leaf extract @ 0.5 kg/4L of water, T5 = Dodder extract @ 0.5 kg/4L of water, T6 = Oleander leaf extract @ 0.5 kg/4L of water, T7= Dhutra leaf extract @ 0.5 kg/4L of water, T8 = Dholkolmi leaf extract @ 0.5 kg/4L of water, T9 = Control. Plant extracts and insecticide were applied at 7 days interval. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. Among the treatments, oleander leaf extract gave the highest percent reduction of aphid infestation (21.69%) over control. Dhutra leaf extract gave the highest percent reduction of jassid infestation (35.42%) over control. Ripcord showed the best efficacy by reducing 66.35% and 31.31% population of mealybug and whitefly, respectively over control. Considering plant and yield related attributes, dholkolmi leaf extract increased the highest percent of plant height (18.21%), leaf per plant (19.81%) and number of branch per plant (39.17%), where neem leaf extract and bullock’s heart leaf extract respectively showed the least performance. Similarly, highest number of fruit per plant, fruit weight, fruit length and fruit diameter (9.83 g, 29.33 g, 15.06 cm and 6.60 cm, respectively) was obtained by application of dhutra leaf extract, tamarind fruit juice and neem leaf extract respectively with the increase of 40.85%, 28.58%, 17.18 % and 30.09 % over control, whereas neem leaf extract (9.73%), dodder extract (11.45%), bullock’s heart leaf extract (23.20%) and dhutra leaf extract (18.07%) showed the least performance. Finaly, the highest yield increase over control was achieved in bullock’s heart leaf extract (40.35%), whereas the lowest increase showed in ripcord (24.34%). All plant materials have great impact on okra yield attributing character and better impact on aphid and jassid and moderate effect on other sucking pests.