Nitrogen Use Efficiency of Rice Crop: Physiological & Biochemical Studies on Nitrogen Use Efficiency in Different Genotypes of Rice (Oryza Sativa L.)

The present study was conducted at the Dr. N. E. Borlaug?s Crop Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, India with an objective to evaluate the effects of different N doses on growth dynamic, morphological, physiological parameters and nitrogen use efficiency in five genotypes of rice. The field experiment was conducted during rainy season of 2008 and 2009. Five rice genotypes (KRH-2- hybrid, Vasumati- aromatic, Tulsi, Kasturi and Krishna Hamsa- high yielding) were used as experimental material. The N fertilizer 0, 50, 100 and 200N kg ha-1 was sprouted in the field. The growth parameters were recorded at time of panicle initiation, maximum tillering and reproductive stage. The growth as well as physiological parameters and guttative fluid increases as the nitrogen levels increased. The grain and biological yieldalso increased with increasing nitrogen levels. The application of nitrogen fertilizers also affected the nitrogen and protein content of leaves, seeds and the soil significantly. The NUE increased up to N100 level and found to be highest for KRH-2.