Effect of nitrogen application on nitrogen uptaking and utilization in ten different rice varieties

Using ten rice varieties of different nitrogen dry matter production efficiency as materials,the effects of four nitrogen treatments on nitrogen dry matter production efficiency(NDMPE),dry matter accumulation(DMA) and nitrogen accumulation(NA) were investigated in pot experiments.The results showed that the nitrogen application increased DMA and NA,but different genotype rice had different increment.With the nitrogen application,the NA and nitrogen content(NC) and DMA increased significantly,but the DMPE obviously declined.The NA was significantly correlated with NC and DMA,the NDMPE was significantly negatively correlated with NA and NC.Significant difference of soil nitrogen apparent balance appeared among different rice varieties,and the difference become more obvious with the increase of nitrogen application.