An experiment was conducted during three consecutive kharif season of 2012, 2013 and 2014 at Raipur in clay soil having neutral reaction, low nitrogen, medium phosphorus and high potassium content to find out effect of levels and scheduling of nitrogen on yield and economics of aerobic rice. The experiment was laid out in split plot design with three replications. Two levels of nitrogen in main plot viz.,120 kg N/ha and 150 kg N/ha and six nitrogen schedules in sub plot viz., S1-2 splits (1/2 at basal+ 1/2 at panicle initiation), S2- 2 splits (1/2 at 10 days after emergence+ 1/2 at panicle initiation), S3- 3 splits (1/3 at basal+ 1/3 at active tillering+ 1/3 at panicle initiation), S4- 3 splits (1/3 at 10 days after emergence+ 1/3 at active tillering+ 1/3 at panicle initiation), S5-4 splits (1/4 basal+ 1/4 at active tillering+ 1/4 at panicle initiation+ 1/4 at flowering) and S6-4 splits (1/4 at 10 days after emergence + 1/4 at active tillering+ 1/4 at panicle initiation+ 1/4 at flowering) was assigned. The test variety was IGKV R1 coarse seed maturing in 125 days and semi dwarf in nature. Application of different levels of nitrogen did not exhibit any significant effect on grain yield, straw yield, net return and B: C ratio of aerobic rice. Pooled data of three years exhibited that higher grain yield, straw yield, net return, B:C ratio and nitrogen uptake were recorded under application of nitrogen in three splits as 1/3 at 10 days after emergence+ 1/3 at active tillering+ 1/3 at panicle initiation which was, however, at par with four splits of nitrogen as 1/4 at 10 days after emergence+ 1/4 at active tillering+ 1/4 at panicle initiation+ 1/4 at flowering stage. Three splitting of nitrogen produced an increase of 16.92 and 1.47% in grain yield, 11.64 and 2.16% in straw yield, 26.78 and 2.90% in net return, 15.71 and 2.37 % in B: C ratio, 41.08 and 6.30% in grain nitrogen uptake, 46.68 and 4.60% in straw nitrogen uptake and 42.28 and 5.86% in total nitrogen uptake as compared to two and four splits, respectively. Application of nitrogen at 10 days after emergence exhibited an increase of 7.80% in grain yield, 5.17% in straw yield, 12.37% in net return, 7.64% in B: C ratio and 13.35% in total N uptake as compared to basal application of nitrogen in aerobic rice.

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