中文摘要：

对绥农14系谱中14个品种进行大田及盆栽试验，揭示同一大豆系谱的产量及相关生理性状演化趋势，探讨未来大豆品种改良的关键性状。结果表明：经过5个世代的杂交重组，鼓粒初期（R5）的光合速率显著增加，绥农14最高，为16．2mmol·m^-2·S^-1，且光合速率的增加与产量显著相关（P〈0．05），但叶面积指数（LAI）没有规律性的变化；通过系统选育，根系形态性状也发生显著变化，从绥农14的早代亲本到晚代亲本，根重、根长及根表面积均有不同程度的提高，但主要表现为生殖生长后期；抗性方面，倒伏级别从4（75％倒伏）下降到1（无倒伏），籽粒病虫害比率也分别从5．3％和20％降低至0和6．8％；生殖生长后期的干物质积累、收获指数及荚粒数的增加与产量的提高密切相关，而百粒重对产量的提高贡献不大。

英文摘要：

With fourteen cultivars in pedigree of Suinong 14, a field and a pot experiment were conducted to evaluate yield- related physiological improvement in a pedigree of soybean, and to seek the crucial traits in need of improving future soybean breeding. The results showed that the photosynthetic rate at the initial seed filling stage（RS） greatly increased after 5 generations of recombination,which contributes to 16.2 mmol.m^ -2.s^-1 of this rate in Suinong 14 ,the highest one among 14 cultivars. Furthermore, the photosynthetic rate had significant relation with yield （ P 〈 0.05 ） , but leaf area index （LAI） had no relation with yield. The root morphological characteristics changed greatly as well. From early to late generation, root weight, root length and root surface area increased to some extent, especially at late reproductive stage. For stress-resistant capability, the resistances of lodging reduced from 4 （75 % of lodging） to 1 of score （ no lodging）, and the percentage of disease and pest seed decreased from 5.3% and 20% to 0 and 6.8% , respectively. The improvement of dry weight accumulation, harvest index and number of pod and seed were closely related with yield increment, but 100-seed weight did not contribute yield improvement that much.