NITROGEN FERTILIZER MANAGEMENT FACTORS AFFECTING NITROGEN USE EFFICIENCY AND YIELD OF RICE (Oryza sativa L.): A REVIEW

Rice is a very fascinating crop because of its higher yield real adoption by farmers and its adaptative to water logged soils. The use of chemical fertilizers is an essential component of modern agriculture but is being checked by sustainability issues. Global food systems are not only failing to keep us all fed, but they are also failing to keep us healthy too. Managing land to produce food, fiber or timber must have some environmental impact, the magnitude of which will depend on the cropping system and the intensity of management. Nitrogen (N) is central to living systems. Nitrogen is a major component of proteins, hormones, chlorophyll, vitamins, and enzymes essential for plant life. The addition of N to agricultural cropping systems is an essential facet of modern crop management and one of the major reasons that crop production has kept pace with human population growth. However, nitrogen fertilizer and its management have been the subject of considerable research and debate for several decades because the benefits of N added to cropping systems come at well-documented environmental costs due to lack of proper management. Excessive rates of N fertilizer can lead to losses of inorganic N from agricultural lands into surface water and groundwater, thereby threatening our environment. Rice production consumes about 20% of the total N fertilizer used for agriculture in the world. N fertilizer is often not effectively used by rice in general and irrigated rice in particular because of improper management. Inefficient N management practices have contributed to low (30–40%) NUE estimates for cereal crops. To achieve high yield and high partial factor productivity of N, a scientifically integrated nutrient management strategy based on a comprehensive understanding of the causes of the crop’s yield and knowledge on the nature of nitrogen fertilizers is mandatory.