中文摘要：

2001～2002年，在群体水培条件下，以不同年代育成的籼稻代表品种国内88个和国外122个为材料，成熟期测定植株的干物重（包括根系）、全氮含量及产量，分析籼稻品种间成熟期氮素累积苣、氮素干物质生产效率和氮素籽粒生产效率的差异及其对产量的影响。结果表明：成熟期氮素累积量、氯素籽粒生产效率和氮素干物质生产效率，品种间差异很大，均达到极显著水平，其中，氮素累积量的差异明显大于氮素籽粒生产效率，氮素籽粒生产效率的差异又明显大于氮素干物质生产效率。相关分析表明，成熟期氮素累积量、氮素籽粒生产效率与籼稻品种的产量水平关系密切，氮素干物质生产效率与籼稻品种的产量水平关系不密切。逐步多元回归分析表明，成熟期氮素累积量和氮素籽粒生产效率对籼稻品种的产量水平均有显著影响（R^2=0．957—0．974），提高成熟期氮素累积量和氮素籽粒生产效率均可提高籼稻品种的产量水平。通径分析显示，籼稻成熟期氮素累积量对产量的直接影响比氮索籽粒生产效率大40％～70％。作者认为，籼稻品种的选育应在保持较高氮索累积量的基础上，重点改良提高氮素籽粒生产效率，有利于实现籼稻品种高产与高效的有机统一。

英文摘要：

Dry matter weight （ including root system）, nitrogen （N） content and grain yield of eighty eight and one hundred twenty two solution-cultured conventional indica rice cuhivars were measured at maturity in 2001 and 2002 to study the differences of N absorption and utilization and their influences on grain yield in the tested cuhivars. Significant differences （ P〈0.01 ） in N accumulation, NUEg （ N use efficiency for grain yield） and NUEp （ N use efficiency for the plant） among cuhivars were found at maturity. Difference among cultivars in N accumulation was larger than that of NUEg, and difference in NUEg was greater than that of NUEp. Grain yield of conventional indica rice cuhivars was not closely related to NUEg but to N accumulation and NUEg. Polynomial stepwise regression analysis showed that grain yield was significantly influenced by N accumulation and NUEg at maturity （R^2 = 0. 957 -0. 974） which indicated that higher yield level could be enhanced by improving N accumulation and NUEg of conventional indica rice cuhivars. Through path analysis, it was also found that the effect of N accumulation on grain yield was more important than NUEg. The results mentioned above suggested that based on high N accumulation at maturity, it was important to improve NUEg to coordinately increase yields and profit.