施氮水平对马铃薯块茎形成期光合特性的影响

Effect of Nitrogen Application Levels on Photosynthetic Characteristics at the Tuber Formation Stage in Solanum tuberosum L.

通过随机区组试验研究了施氮水平对马铃薯块茎形成期叶片光合特性的影响。结果表明,施氮可促进叶绿素合成,提高气孔开闭变化幅度、光合光响应灵敏度及光能转化效率;低氮对马铃薯块茎形成期光合特性的影响程度较中、高氮处理小,光合作用自身气孔调节能力以施中氮处理最高;随施氮水平提高,马铃薯块茎形成期光补偿点(LCP)、表观量子效率(Φ)、最大净光合速率(Pmax)、表观暗呼吸速率均逐渐提高,高氮处理具有更高光能转化效率。

This study analyzed the effect of nitrogen application levels on photosynthetic characteristics in the period of tuber formation by randomized blocks trial.The result indicated that nitrogen application promoted synthesis of chlorophyll,increased the scope of stoma＇s open or shut,increased the light sensitivity of photosynthesis and conversion efficiency of light energy;the effect of low nitrogen level on photosynthetic characteristics was smaller than that of middle and high nitrogen level.Capability of stoma adjusted by photosynthesis was the highest at middle nitrogen level;with the increasing of nitrogen application levels,the light compensation point（LCP） of potato leaf,apparent quantum efficiency（Φ）,maximum net photosynthesis rate（Pmax）,and apparent dark respiration rate（Rd） were increased.