稀盐盐生植物盐角草对盐胁迫生理响应的初步研究

Preliminary Study on the Physiologic Response of Salt-dilution Halophyte Salicornia europaea L. to Salt Stress

【目的】分析盐胁迫下盐角草生长特性指标和抗逆性指标的变化,初步研究盐角草对盐胁迫的耐盐机理。【方法】用不同浓度的NaCl对盐角草进行盐胁迫处理,常规方法测定盐角草的湿重、干重、含水率、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶(CAT)活性、脯氨酸含量和丙二醛(MDA)含量。【结果】随着NaCl浓度的不断增加,盐角草湿重、干重和含水率均呈先升后降再升趋势,最适生长浓度为100mmol/L;叶绿素含量先降后升;SOD活性总体呈先升后降,POD活性和CAT活性则是先降后升再降,三者相互协调发挥作用;脯氨酸含量、MDA含量呈先升后降态势,且盐处理后的均较对照的高。【结论】盐角草的抗氧化酶活性,尤其是SOD活性是盐胁迫的敏感指标,反应了盐角草独特的耐盐机理。

【Objective】The aim of this project was to analyze the changes of growth and resistance characteristics of Salicornia europaea L.under salt stress to study the mechanism of salt resistance of S.europaea.【Method】The characteristics such as fresh weight,dry weight,water ratio,chlorophyll content,superoxide dismutase（SOD）,peroxidase（POD）,and calatase（CAT） activities,malondidehyde（MDA） and free proline content of S.europaea treated with different concentration of NaCl stress were determined by conventional method.【Result】The fresh weight,dry weight and water ratio were increased first,then decreased,and finally increased with the increasing NaCl concentrations,and 100 mmol/L was the optimal concentration for S.europaea.Chlorophyll content increased first and then decreased.The activity of SOD gradually increased first and decreased finally with the increase of NaCl concentration while the activity of POD and CAT increased first,then decreased,and finally increased.MDA content and free proline content went up and then dropped.However,the contents of S.europaea.under NaCl stress were higher than those of S.europaea.cultured without NaCl.【Conclusion】In conclusion,the study results showed that the antioxidative enzyme activity of halophytes,especially the activity of SOD,is a sensitive index to salt stress.This reflected the special mechanism of salt resistance of S.europaea.