Yield and economics of direct seeded rice as influenced by nitrogen and weed management practices

A field experiment was conducted at Agricultural Research Farm, Institute of Agricultural sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, during rainy (kharif) season of 2015 and 2016 to study the effect of nitrogen and weed management in direct seeded rice (Oryza sativa L.) under irrigated condition. The experiment comprised of 24 treatments including all the combinations of 4 nitrogen and 6 weed management treatments. The results indicated that the maximum filled spikelets, fertility percentage, yield, gross returns, net returns and B: C ratio were recorded under nitrogen application of ¼ N basal + ¼ N at active tillering stage + ¼ N at panicle initiation stage + ¼ N at heading stage which was statistically at par with 1/3 N at basal + 1/3 N at active tillering stage + 1/3 N at panicle initiation stage and significantly higher than remaining nitrogen treatments. The minimum filled spikelets, fertility percentage, yield, gross returns, net returns and B:C ratio were recorded under nitrogen application of ½ N basal + ¼ N at active tillering stage + ¼ N at panicle initiation stage. Among weed management practices, significantly the maximum filled spikelets, fertility percentage, yield, gross returns, net returns and B:C ratio were recorded under application of bispyribac at 25 g a.i. ha-1 + azimsulfuron at 17.5 g a.i. ha-1 + NIS (0.25 %) at 15-20 DAS was significantly superior over other treatments.