EFFECTIVE SPRAY SCHEDULE OF CYPERMETHRIN FOR MANAGING POD BORER ATTACKING SUMMER COUNTRY BEAN

ABSTRACT: The study was conducted in order to find out an effective spray schedule of cypermethrin insecticide against pod borer, Maruca vitrata F. attacking summer country bean. Including an untreated control there were six treatments were used to measure the effectiveness of cypermethrin based on inflorescence and pod infestation, yield and also benefit cost ratio (BCR). Among the different spray schedules of cypermethrin, the lowest rate of pod infestation (4.59% by number and 6.10% by weight) and the highest BCR (6.98) were obtained with Ripcord (cypermethrin) 10 EC @ 1 ml l-1 of water sprayed after observing 5% level of pod infestation and repetition of the same at 15 days interval up to last harvest. On the other hand, highest marketable yield (11.64 t ha-1) was obtained Ripcord (cypermethrin) 10 EC @ 2 ml l-1 of water sprayed after observing 5% level of pod infestation and repetition of the same at 15 days interval up to last harvest but the BCR was lower (4.21) compare to the application rate 1 ml l-1 of water. So, Ripcord (cypermethrin) 10 EC @ 1 ml l-1 of water sprayed after observing 5% level of pod infestation and repetition of the same at 15 days interval up to the last harvest performed the best.

Keywords: Spray schedule, Cypermethrin, Maruca vitrata, Summer country bean.