EFFECT OF DIFFERENT APPLICATION METHODS OF IMIDACLOPRID ON ABUNDANCE AND MANAGEMENT OF JASSID IN OKRA

Abstract

A field study was carried out in the farm of Sher-e-Bangla Agricultural University during May to June, 2009 to investigate the effect of different application methods of imidacloprid on abundance and management of jassid in okra. The population of jassid was gradually increased with the age of the crop and the peak population was found on last week of May and it was remained constant after that. The lowest number of jassid (16.47/plant) was found in T2 (seed treatment by Gauchu 70WS + foliar spray with Admire 200SL), which reduced 77.71% population of jassid over control. Plant height, number of fruits/plot and yield per plot were significantly increased under different treatments. The highest plant height (244.8 cm), number of fruits/plant (652) and yield (13.84 t/ha) were observed in T2 (seed treatment by Gauchu 70WS + foliar spray with Admire 200SL) treated plot. The result of T4 (seed treatment by Gauchu 70WS + band application of Gauchu 70WS) and T5 (pre-plant injection by Gauchu 70WS at a depth of 4cm below the seed line + foliar spray with Admire 200SL) were statistically similar with T2 (seed treatment by Gauchu 70WS + foliar spray with Admire 200SL) treated plot. The highest benefit cost-ratio (BCR) was obtained in T1 (23.22) and the highest adjusted net return (Tk. 41,300) was obtained in T2 which was found as the best treatment in this study. Considering jassid population, plant growth, number of fruits and fruit yield, T2 (seed treatment by Gauchu 70WS + foliar spray with Admire 200SL) was the most effective application methods.