Fertiliser N has played a key role in increasing food grain production in India and will continue to do so in future. India is currently consuming about 14.4% of the world's total consumption of fertiliser N, a little more than USA but about half of that by China. Cereals are the staple food in India and about 69% of the total fertiliser consumed in India is applied to cereals, out of which rice and wheat consume about 61%. Rice and wheat are the backbone of India's self-sufficiency in food production and make-up to about 81% of the total cereal production in the country. These two crops cover up to 52 % of the total area under cereals and 31% of the total cultivated area. Globally the value of apparent recovery of fertiliser N is 55%, while true recovery (TREn) is 44%. TREn values are specially low in rice; in India these vary from 21-33%. Agronomic efficiency value of 4-17 kg grain/kg N in rice-wheat cropping system is very low. Enhancement of NUE can be achieved by following the best crop management practices to achieve good yields, adopting right method and timing of fertiliser application and practicing balanced NPK application, site specific nutrient management and integrated nutrient management. Seven 'R's of the 'road to enhanced NUE' are: 1, Optimum rate, 2. Eight source, 3. Right time of application, 4. Right placement, 5. Might balance of primary, secondary and micronutrients, 6. Recycling the plant nutrients by using more and more organic manures and crop residues and 7. Eeliance on biological nitrogen fixation to some extent.
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