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A field experiment was conducted in alkali soils of A.D. Agricultural College and Research Institute farm Tiruchirappalli, Tamil Nadu, in wet season (September to January) of 2006-07 and 2007-08 to study the effect of amendments viz., gypsum and distillery spentwash (DSW) and nutrient omission plots on yield, nutrient use efficiency and fertilizer N, P and K requirement of rice. In both years, reclamation of alkali soils with DSW recorded the highest grain yield of 6.58 Mg ha^-1 followed by gypsum @ 50% GR (5.94 Mg ha^-1). Among the nutrient omission plots, application of recommended dose of NPK (RDN) recorded significantly higher rice grain yield of 6.98 Mg ha^-1. In DSW reclaimed alkali soils, N limiting yield was 6.79 and 6.33 Mg ha^-1 during first and second year respectively which were 43 and 36 per cent higher than gypsum reclamation. But the effect of amendment on P limiting yield during the second year and K limiting yield on both years were not significant. The N, P and K requirement to produce one tonne of rice grain varied between 17. 3 to 25.5, 3.9 to 4.9 and 21.7 to 56.5 kg Mg^-1 of grain respectively. For a yield target of 7.0 Mg ha^-1, the mean fertilizer N requirement was higher under no amendment followed by gypsum and DSW reclamation. The mean fertilizer P₂O₅ requirement was 30 per cent less than RDN while mean fertilizer K₂O requirement was 60 per cent higher than RDN.

Key words: Distillery spent wash for reclamation, fertilizer requirement of rice, Site Specific Nutrient Management