中文摘要：

为探明油菜氮高效的生理机制,采用砂培试验在2种氮水平条件下研究了3个不同油菜品种在苗期、开花期和角果发育期的光合作用与干物质积累对氮效率的影响。结果表明：在氮胁迫条件下,不同油菜品种苗期和角果发育期的叶片光合速率对氮效率的影响较大,而3个生育期干物质积累对氮效率的影响都较小。在正常供氮条件下,不同油菜品种苗期和角果发育期的叶片光合速率以及3个生育期的干物质积累对氮效率的影响都较大。

英文摘要：

In order to investigate the physiological mechanism of nitrogen use efficiency（NUE） of oilseed rape,sand experiments were used to study the influences of photosynthesis and dry matter accumulation of three different oilseed rape cultivars on nitrogen use efficiency at seedling stage,flowering stage and podding stage under two supply levels of nitrogen.The results showed that under the nitrogen threatening,the photosynthetic rate of different oilseed rape cultivars at seedling stage and podding stage had large impact on NUE,while the dry matter accumulation of different oilseed rape cultivars at three growth stages had small impact on NUE.Under the normal supply of nitrogen,the photosynthetic rate at seedling stage and podding stage and the dry matter accumulation at three growth stages of different oilseed rape cultivars all had great impact on NUE.