[Nitrogen use efficiency and its relationship with nitrogen nutrition characteristics of wheat varieties]

Forty wheat varieties were tested at two sites (Xuzhou and Nanjing) to evaluate genotypic and environmental variation of nitrogen use efficiency (NUE) and its relationship with nitrogen nutrition characteristics. It was shown that genotype had significant effect on NUE, but environment had less effect on NRE and NFE. All of the nitrogen nutrition traits were significantly influenced by the interaction of genotype x environment. NFE, as an integrated index reflecting the differences of grain yield and nitrogen utilization among different wheat varieties, was significantly correlated with NRE, NPP and NPS, which indicated that it should be more useful in evaluating nitrogen use efficiency. NFE could be improved by increasing N assimilation and translocation after anthesis to effectively increase the N utilization of wheat.