中文摘要：

采用田间试验，在常规氮素管理下，以氮素吸收效率（NAE）、利用效率（NUE）和收获指数（NHI）为衡量指标，分析了国内外607份不同类型水稻种质氮素营养效率的变异状况。结果表明，水稻NAE、NUE和NHI存在显著的基因型差异，以NHI为最大和NAE为最小。不同类型水稻间的NAE、NUE和NHI未达显著差异，但籼型杂交稻NAE、NUE和NHI的变异小于常规籼稻和常规粳稻。相关分析表明，水稻NAE与NUE、NHI呈极显著负相关，NUE与NHI间无显著相关；水稻NUE和NHI与单株产量存在极显著的正相关，NAE与单株产量无显著相关。频数分析可知，常规籼稻NAE、NUE及NHI和籼型杂交稻NUE的种质频数分布呈典型正态曲线，低、高效种质较少，中效种质众多；常规粳稻NAE、NUE和NHI种质的频数分布呈近似正态分布，略偏向低效；籼型杂交稻NAE的种质频数分布离散程度较高和高效种质较多，NHI的种质频数分布呈近似正态分布和略偏低效。籼型杂交稻的NAE、NUE和NHI差异小而分布较集中，常规粳稻最分散，常规籼稻居中。不同类型水稻的氮素营养效率的极差很大，可分为若干组，各组间差异显著。

英文摘要：

Field experiment was conducted to investigate the variations of nitrogen absorption efficiency （NAE）, nitrogen utilization efficiency （NUE） and nitrogen harvest index （NHI） in 607 rice germplasms （including conventional indica, japonica and hybrid indica combination rice）. The results showed that genotypic differences of NAE, NUE and NHI obviously existed among these rice germplasms, with maximum coefficient of variation in NHI and minimum in NAE. There were not significant differences among conventional indica rice, conventional japonica rice and hybrid indica rice combinations, but the variations of NAE, NUE and NHI in hybrid indica rice combinations were lower than those in conventional indica and japonica rice. Correlation analyses indicated that the correlations of NAE to NUE and NHI in rice were very significantly negative, and the correlations of NUE and NHI to yield per plant were very significantly positive, but the correlations of NUE to NHI and NAE to yield per plant were not significant. The distributions of rice germplasms based on single NAE, NUE or NHI in conventional indica rice and NUE in hybrid indica rice combinations resembled typical normal curve, namely that low and high efficient germplasms were fewer and medium efficient germplasms were more. The distributions of rice germplasms based on single NAE, NUE or NHI in conventional japonica rice and NHI in hybrid indica rice combinations resembled normal curve approximately. The distributions of rice germplasms based on NAE in hybrid indica rice combinations were very sporadic and high efficient germplasms were more. Furthermore, the distribution of hybrid indica combinations was concentrative with small variation on NAE, NUE and NHI, but that of conventional japonica rice was much scattered. The ranges of NUE and NHI in three rice types were so large that they could be classified into some clusters. The differences among clusters were significant.