中文摘要：

本研究通过人为控制土壤盐分梯度,以盆栽当年生紫穗槐幼苗为材料,研究不同盐分条件下紫穗槐叶片光合速率、酶活性、有机渗透调节物质等生理特性,探讨紫穗槐耐盐机制。结果表明,随盐分胁迫程度的加剧,紫穗槐幼苗的净光合速率（Pn）、蒸腾速率（Tr）、气孔导度（Gs）、K＋含量逐渐下降,超氧化物歧化酶（SOD）活性、过氧化物歧化酶（POD）活性、Na＋、可溶性糖和游离脯氨酸含量则显著上升;叶绿素a、叶绿素b、叶绿素总量、类胡萝卜素含量随土壤盐分浓度的增加逐渐增大,而叶绿素a与叶绿素b含量之比无显著变化。以上生理指标反映出紫穗槐幼苗对盐渍环境的适应性变化,是其抵御逆境的一种积极调节机制。

英文摘要：

Physiological characteristics of Amorpha fruticosa leaves,including photosynthetic rate,enzyme activity,organic osmolytes etc.were studied under different soil salt concentrations.The mechanism of salt-tolerance in A.fruticosa is discussed.The net photosynthesis rate（Pn）,transpiration rate（Tr）,stomatal conductance（Gs） and the content of K＋ decreased with reduced severity of salt stress,while the activities of SOD and POD,the contents of soluble sugar,free praline（Pro） and Na＋ noticeably increased.The contents of chlorophyll a（Chla）,chlorophyll b（Chlb）,total chlorophyll（Chl） and carotenoid pigment increased along with the increase in soil salt concentrations,but,the ratio of Chla/Chlb showed no significant change.The results show that the improvement of leaf salt-tolerance in A.fruticosa seedlings resulted from the modulation of physiological characteristics and A.fruticosa had certain salt-tolerant characteristics.