Nitrogen Use Efficiency of Wheat and Transplant <i>Aman</i> Rice under Bed Planting Method in Rice-Wheat Cropping System

Abstract

An experiment was conducted at the Bangladesh Rice Research Institute (BRRI) experimental farm, Gazipur and at farmer's field in Chuadanga during Rabi season 2001-02 (November - March) to Kharif-II season 2002 (June - November) to determine the effect of different doses of N fertilizer on growth and yield of wheat and transplant Aman rice and to compare the N use efficiency in bed planting and conventional method in rice-wheat cropping system. Bed planting with 0, 60, 80, 100 and 120 kg N ha-1 and conventional (flat) method with 0 and 100 kg N ha-1 were tested. The yields increase of wheat in bed planting with 80, 100 and 120 kg N ha-1 over 100 kg N ha-1 in conventional method were 10-21, 20-29 and 23-38%, respectively. For transplant Aman rice, bed planting with 80, 100 and 120 kg N ha-1 and conventional method with 100 kg N ha-1 produced statistically identical grain yield. Bed planting increased the grain number panicle-1 and reduced sterility of both wheat and transplant Aman rice. Nitrogen use efficiency such as partial factor productivity and agronomic efficiency were higher in bed planting than conventional method and it saved about 20% N without losing yield of wheat and transplant Aman rice. Key words: Nitrogen use efficiency, rice, wheat and bed planting. DOI: 10.3329/jard.v7i1.4420 J Agric Rural Dev 7(1&2), 41-49, June 2009