An inside into the nitrogen use efficiency and its importance in crop production

Abstract

Agriculture is the backbone of developing countries and plays a vital role in sustaining human society. Agricultural production is highly dependent on the use of synthetic fertilizers, among all nitrogenous fertilizer rank first. With increasing use of global nitrogen (N) fertilizers tremendously; at the beginning of the decade it was around 87 million metric tons, is estimated to increase up to 236 million metric tons by 2050. Heavy use of nitrogenous fertilizer to the farmland has resulted in a dramatic increase in crop yield but with considerable negative impacts on the environment. Nitrogen use efficiency (NUE) of most of the crops particularly cereals is very low that is around 30-35%, remaining 60-65% N is lost in the environment due to runoff, leaching, volatilization, denitrification, etc. The ability of plants to effectively utilize N from the soil depends on a number of factors including N uptake, assimilation, translocation and remobilization during senescence. The innate efficiency of the plant to utilize this available N can be increased with proper phenotyping, identification of genotypes with high NUE, molecular breeding approaches, and targeting candidate genes for the improvement of NUE. The present review highlights the physiological and genetic basis of NUE and its related traits in enhancing crop productivity.