Response of hybrid and inbred rice (Oryza sativa) to nitrogen in central alluvial tract of Uttar Pradesh

Field experiment was conducted during two consecutive wet seasons (kharif) of 2005 and 2006 to assess the response of hybrid and inbred rice (Oryza sativa L.) to various levels of nitrogen in upland condition of central alluvial tract of Uttar Pradesh, India. Among the hybrids, ‘KRH-2’ recorded maximum grain (6.16 t ha⁻¹) and straw (8.20 t ha⁻¹) yield, yield attributing characters, nitrogen uptake and protein content, closely followed by hybrid ‘PHB-71’. All the growth and yield attributing characteristics, grain and straw yield, nitrogen uptake and protein content enhanced markedly with increasing levels of nitrogen up to 180 kg ha⁻¹. The magnitude of the effect of highest dose of N i.e. 180 kg ha⁻¹ increased 73.6, 23.9 and 6.2% in grain yield, and 79.1, 26.3 and 5.6% in straw yield over control, 60 and 120 kg N ha⁻¹, respectively.