Response pattern of local, inbred and hybrid monsoon rice varieties to elevated nitrogen levels

Abstract

The experiment was conducted at the Bangladesh Agricultural University during July to December 2017 to investigate the response of local, inbred and hybrid rice varieties to elevated nitrogen fertilizer application. The experiment comprised two factors such as factor A: nitrogen levels viz., control (without N fertilizer), 40, 80, 120, 160 and 180 kg N ha-1; factor B: rice varieties viz., Latma (local), BRRI dhan49 (inbred) and Agrodhan-12 (hybrid). Experiment was laid out in a Split-plot design with three replications where nitrogen levels were assigned to main plots and varieties were to sub-plots. Nitrogen levels, varieties and their interactions significantly influenced the yield contributing characters and yield of rice. Agrodhan-12 fertilized with 120 kg N ha-1 produced the highest grain yield which was statistically similar to BRRI dhan49 interacted with 80 kg N ha-1. The lowest yield was obtained from Latma without N fertilizer. The treatment 40 kg N ha-1 resulted the highest nitrogen use efficiency. In terms of yield and economic performances, 120 kg N ha-1 performed best. Based on these results it may conclude that 120 kg N ha-1 is the optimum dose for hybrid Agrodhan-12, whereas 80 kg N ha-1 for local Latma or inbred BRRI dhan49.