盐角草幼苗对盐离子胁迫生理响应的特性研究(简报)  

Study of characteristic response to salt-ion stresses of Salicornia europaea seedlings

作　　者：郑青松[1,2] 华春[3] 董鲜[1] 李秀华[1] 陈刚[2,4] 

机构地区：[1]南京农业大学资源与环境科学学院,江苏南京210095 [2]江苏省作物栽培生理重点实验室,江苏扬州225009 [3]南京晓庄学院生命科学系,江苏南京210017 [4]扬州大学生物科学与技术学院,江苏扬州225009

出　　处：《草业学报》2008年第6期164-168,共5页Acta Prataculturae Sinica

基　　金：江苏省重点实验室开放课题(k04009);江苏省博士后基金资助计划(0701015C);江苏省教育厅自然科学基金(05KJD180118)资助

摘　　要：研究盐角草幼苗对不同盐离子处理和不同水平盐度的响应和体内的盐分分布，试图探索离子吸收分配与其高盐适应的关系。结果表明，与对照相比，等渗条件（-0．88MPa）下处理12d，不同盐处理均明显刺激盐角草幼苗生长，其鲜重、干重、肉质化程度显著增加，其中NaCl处理的肉质化程度促进效应最大。等渗条件（-0．88MPa）下处理24d，NaCl处理的生长促进效应更明显，其幼苗肉质化程度显著高于其他处理，Cl^-处理仍然保持一定的生长促进效应，而Na^＋处理的幼苗生长明显受到抑制。盐角草幼苗的生长既需要Na^＋，也需要Cl^-，300～400mmol／LNaCl为其生长的最适浓度，盐角草对高盐的适应性主要在于植株维持K^＋稳态的能力很强，其Na^＋、K^＋吸收和K^＋／Na^＋选择性相关的耐盐机制与非盐生植物显然不同，推断盐生植物盐角草很可能具有各自独立的Na^＋、K^＋吸收载体或通道系统。其差别可能正是盐生植物与非盐生植物耐盐性不同的原因所在。Salicornia europaea seedlings were examined for their performance under different salt-ion stresses （--0.88 MPa, Na^＋ , Cl^-, NaCl） and for their tolerance to a wide range of NaCl concentrations （100-1 000 mmol/L） in the laboratory. The distributions of salts and ionic absorption in S. europaea under 100--1 000 mmol/L NaCl treatments were also studied. Treatments with different salts of the same osmotic potential for 12 days all promoted growth of S. europaea seedlings, with the best effect from the NaCl treatment. When plants were treated for 24 days, growth of S. europaea seedlings was still stimulated under treatments of Cl^- alone or NaCl, while growth was inhibited under Na^＋ stress. The growth under NaCl was much better than that under the Cl-alone treatment, suggesting that both Na^＋ and Cl^- were beneficial elements for the growth of S. europaea seedlings. Our results also showed that 300-400 mmol/L NaCl was the optimum concentration for growth. K^＋ content in roots did not show significant change at less than 100--200 mmol/L NaC1, and Na^＋ content in roots did not change at less than 100 mmol/L NaCl. As NaCl concentration was increased （〉200 mmol/L）, K^＋ content in roots decreased markedly. When NaCl was above 700 mmol/L, K^＋ content in roots did not decrease further. Root SK, Na increased greatly with an increase in NaCl concentration, suggesting that K^＋ absorptive selectivity was higher under NaCl treatments. In S. europaea shoots, K^＋ content was decreased at low concentrations of NaCl but did not decrease further when NaCl in the medium exceeded 200 mmol/L. The results suggested that maintaining K^＋ homeostasis was a notable characteristic of S. europaea shoots. We conclude that an increase in K^＋ absorptive selectivity in roots and maintenance of K^＋ homeostasis in shoots may contribute to S. europaea＇s tolerance to high salt concentrations, implying the existence of unique Na^＋ , K^＋ absorptive carriers or channel systems in S. europaea.

关 键 词：盐角草 幼苗 等渗 NACL 生长 肉质化 K^+稳态 

分 类 号：S540.34[农业科学—作物学] Q945.78[生物学—植物学]