摘要： 以韭菜叶片为试材，研究了不同光强下外源水杨酸(SA)对韭菜硝酸盐含量和光系统Ⅱ(PSⅡ)活性的影响。结果表明，随着光照强度的增加，氮还原动力泵硝酸还原酶(NR)活性逐渐升高，硝酸盐含量逐渐下降。叶面喷施SA后均可提高不同光强下NR活性，硝酸盐累积明显减小，在100%自然光下表现最为显著。10%～70%自然光下，外源SA可明显提高韭菜叶片的叶绿素含量，光吸收、光能利用和能量转化效率，促进了光系统Ⅱ的活性，而100%自然光下这种增加效果不明显。

关键词: 韭菜, 水杨酸, 硝酸盐累积, 光系统活性

Abstract: Effects of exogenous salicylic acid (SA) on nitrate acuumulation and PST activity under different lightintensity in the leaves of Chinese chive were studied. The results indicated that with increasing light intensity the ac-tivity of nitrate reductase ( NR) was increased and the nitrate content was decreased. The activity of NR was significant-1y increased and the nitrate content was decreased obviously by spraying on leaves with exogenous SA than compari-son Specially under 100% natural light. Exogenous SA may significantly enhance chlorophyll content optical absorp-tion light utilization energy conversion efficiency and activity of PST under 10%－ 70% natural light however theeffect is not obvious under 100% natural light.

Key words: Chinese chive, Salicylic acid, Nitrate acuumulation, Photosystem activity

中图分类号: 

• S633.3