Abstract

                               A field experiment was conducted at Anbil Dharmalingam Agricultural College and Research institute, Thiruchirappalli during Samba season 2015-16 to optimize the nitrogen dose for green manure incorporated paddy field under sodic soil. The experiment was laid out in Randomized block design (RBD), with three replications. The treatments consists of green manure (GM) alone, green manure + 100% recommended dose of nitrogen, green manure + 75% recommended dose of nitrogen, green manure + LCC based nitrogen management, green manure + skipping N during tillering stage, 100% recommended dose of nitrogen alone and control (No nitrogen). The results revealed that the green manure + 100% N recorded significantly higher growth, yield parameters and grain yield (5900 kg ha-1), net returns and BCR over green manure alone. However, the grain yield was comparable with GM + 75% N, GM + skipping N during tillering stage, GM + LCC based nitrogen management. Since the grain yield recorded under GM + 100% N was statistically on par with GM + 75% N, 25% of nitrogen could be saved through green manuring. Hence the recommended dose of nitrogen could be reduced from 187.5 kg to 140.6 kg ha-1 (75%) for green manure incorporated rice under sodic soil.

Key words :Green manure, Nitrogen, Rice, LCC, Optimization, Grain yield, Economics