盐胁迫对蓖麻Na+、K+吸收分布和叶绿素荧光的影响

目的]探讨蓖麻的耐盐机制。方法]比较了栽培蓖麻淄蓖6号和天然生长于滨海盐碱地的野生蓖麻体内K+、Na+的分布特点、叶绿素荧光参数、植株生长状况和叶片渗透调节能力对NaC l处理的响应。结果]野生蓖麻较栽培蓖麻具更明显的喜盐特性;蓖麻的耐盐机制在于促进K+的吸收和向地上部的运输,进而维持叶片的K+/Na+平衡;通过维持光系统Ⅱ的稳定性进而维持盐胁迫下叶片的光合速率。结论]该研究为蓖麻在盐碱滩涂地的推广应用提供了理论依据。

Absorption and Distribution of Na+, K+ and Chlorophyll Fluorescence in Castor under Salt Stress

Objective] The aim of this study is to reveal the salt resistance of castor.Method] Under salt stress,the growth,osmotic potential,chlorophyll fluorescence parameters,Na+ and K+ uptakes and transports in the seedlings of two Ricinus communis varieties(cultivar castor Zibi 6 and wild castor which grew naturally in coastal saline-alkali land) were comparatively studied.Result] Wild castor preformed better in halophilism than that of cultivar castor Zibi 6 under the NaCl treatment.One of the salt tolerant mechanisms of castor is to improve K+ uptake and transport to overground portion,thus to maintain K+/Na+ homeostasis in leaves;on the other hand,the high stability of Photoreaction System Ⅱ(PS Ⅱ) plays a key role in maintaining the leaf photosynthetic rate under salt stress.Conclusion] The results of this study provided theoretical basis for the extension and application of castor in saline beach.