Advances in genetic basis of nitrogen use efficiency of rice

Nitrogen is one of the fundamental key element required for crop growth and development. Excessive use of N in crop production has become a major global concern as it is causing environmental degradation through soil–water and also atmosphere. Increasing N use efficiency (NUE) and a balance of crop yields to achieve food security is the need of current situation. It is also important that, judicious application of N along with developing N efficiency crops are to be targeted for reducing the global climate change impacts. Ample opportunities existing in the form of germplasm resources which are yet to be utilized, advancement of genetic tools such as QTLs, genes associated with N metabolism, proteomics, association mapping, microarray, miRNA, genetic transformation and transcriptomic strategies are yet to be fully implemented to decipher the secrets of natural efficiency of N in crop plants. Progress of N use efficient developed using some of the above tools in a multidisciplinary mode and the first set of improved N efficient rice lines are field tested so as to understand genetic basis of NUE.