Effect of inorganic and organic sources of nutrient on NPK content, NPK uptake, apparent nitrogen recovery, nitrogen use efficiency and Protein content in rice under rice wheat cropping system

Food security is a major global issue because of the very fast growth of population with decreasing natural resources. Rice (Oryza sativa L.) is the most important staple cereal crop in the world. Application of nitrogen (N) fertilizer has improved crop yield in the world during the past five decades but with considerable negative impacts on the environment. New solutions are therefore urgently needed to simultaneously increase yields while maintaining decreasing applied N to improve the nitrogen use efficiency (NUE) of crops. Plant NUE is inherently complex with each step (including N uptake, translocation, assimilation, and remobilization) governed by multiple interacting genetic and environmental factors. Based on the current knowledge, researcher developed some possible approaches for enhancing NUE, by molecular manipulation of genes and integrated nutrients management practices for improving NUE. Development of integrated research approaches, mainly based on whole-plant physiology, quantitative genetics, forward and reverse genetics, agronomical approaches to improve NUE, is a major objective in the future.