Productivity and economic assessment of diverse rice (Oryza sativa L.) varieties with varied nitrogen levels in eastern indo-gangetic plains

During the Kharif seasons of 2020 and 2021, a field experiment was performed at the IndianAgricultural Research Institute (ICAR), Regional Station, Pusa, Bihar, to investigate the impact of different rice varieties and nitrogen levels on growth, yield, and economic aspects. Five varieties of rice, namely PNR 381, Rajendra Sweta, Sugandha-5, Pusa Sambha-1850, and Pusa-44, along with five nitrogen levels (0, 60, 120, 180, and 240 kg N/ha), were assessed.A progressive improvement in growth parameters and yield as nitrogen levels increased from the control to 200% recommended dose of nitrogen (RDN) equivalent to 240 kg/ha. The application of nitrogen at 240 kg N/ha resulted in significantly elevated plant height (102.1 cm), panicle length (27.1 cm), 1,000 grain weight (21.3 g), grains per panicle (200.9), grain yield (4.94 t/ha), net returns (₹ 61104/ha), and B:C ratio (2.27), as well as increased gross energy output, net energy return, energy use efficiency, and energy productivity. The Pusa-44 variety demonstrated superior performance compared to the other varieties tested. In conclusion, for the calcareous soil of the Indo-Gangetic Plains, cultivating the Pusa-44 rice variety along with the application of 150% RDN (180 kg N/ha) emerges as the optimal strategy to improve productivity, profitability and energetic.