Nitrogen uptake and N use efficiency in hybrid and common rice as influenced by nitrogen fertilization

Nitrogen uptake and N use efficiency in hybrid and common rice as influenced by nitrogen fertilization were studied in a field experiment. Nitrogen content in rice plant was affected significantly by both genotype and nitrogen fertilization. N content increased with N uptake rate in all plant parts. The grain contained 66, 59 and 60% of total N at N0, N1 and N2 levels, respectively. The interaction effect of genotype and nitrogen rates on N content in leaf at tillering and heading and in grain at maturity was significant. Both genotype and nitrogen fertilization affected physiological N use efficiency significantly and higher PNUE was observed in common rice. Agronomic N use efficiency and efficiency of fertilizer N didn't differ significantly among genotypes and N rates.