【摘要】 夏大豆花芽分化前的光合产物对产量贡献很小。花芽分化至鼓粒前是夏大豆产量形成的关键时期。这一时期营养生长和生殖生长竞争激烈，对外界环境敏感，栽培措施应以调节干物质分配流向为主，争取早分化、稳长。鼓粒后，全株的干物质积累仍维持较高水平，延长后期光合器官功能，防止早衰，将有利于减少秕粒，提高百粒重。更多还原

【Abstract】 The synthetic materials produced by photosynthesis to the flowering-beginning prior period of summer soybean is not significantly contributive to yield. The important period in deciding future yield is the stage of flowering-beginning.There are strong competition between the vegetative growth and the reproductive growth for the synthetic material. Plants are sensitive to the outside circumstances,SD the adjustment of the distribution of the dry matter should depend upon cultivation for normal flowering and steady growth.After pod-filling, accumulation of dry matter in the whole plant are still kept at high level. Extending the function of photosynthesis organs inflater-afage and preventing premature are elpful to reducing abortive seeds and enhancing seed grain weight.更多还原