Physiological approaches for increasing nitrogen use efficiency in rice

Nitrogen (N) plays an important role in plant growth, development and also one of the major factor for developing a high-yielding rice cultivars. Nitrogen use efficiency (NUE) in plants is a complex phenomenon that depends on a number of internal and external factors, which include soil N availability, its uptake and assimilation of carbon and nitrogen. An increased awareness of the regulatory mechanisms controlling Nitrogen economy is imperative to enhance nitrogen uptake and use efficiency so as to reduce excessive input of fertilizers, while maintaining an acceptable yield. The physiological, biochemical, molecular aspects like QTL, mi RNA technology and transgenic approaches as well as NUE can be targeted to improve rice productivity. Yield being complex and multigenic trait linkages between carbon and nitrogen pathways are essential. An attempt on complex interactions between the two major physiological pathways linked by photosynthesis and photorespiration in global climate change for enhancing NUE in relation to rice yield was reviewed. © 2013 Indian Society for Plant Physiology.