In a pot experiment, various nitrogenous fertilizers and nitrification inhibitors were evaluated at varying N levels in rice (Oriza sativa L.) during kharif seasons of 2003 and 2004 at Kanpur, Uttar Pradesh. Maximum amount of ammonical nitrogen in soil was observed under N-Serve, a nitrification inhibitor. N-Serve treated urea also had highest 1000-grain weight, and grain and straw yields as well as nitrogen content in rice. Maximum nitrogen use efficiency was obtained with N-Serve treated urea, followed by DCD (dicyandiamide) and neem cake coated urea. The nitrogen use efficiency declined but grain yield increased linearly with incremental dose of nitrogen. Protein content in rice increased significantly with increasing doses of nitrogenous fertilizer but it was maximized with the application of oxamide, another nitrification inhibitor.
Nitrogen inhibitors, Nitrogen use efficiency, Rice, Slow release nitrogenous fertilizers, Yield
