2年生酸枣移栽苗生理变化及其耐盐性

Research on the Physiological Change of the Two Year Old Transplanted Seedlings of Wild Jujube and Their Salt Tolerance

【目的】对2年生酸枣移栽苗进行耐盐性评价,为其在新疆盐渍化地区扩大种植面积提供依据。【方法】以2年生酸枣移栽苗为材料进行不同程度的NaCl胁迫处理,研究其细胞膜透性、丙二醛(MDA)含量以及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性和渗透调节物质含量的变化趋势。【结果】将2年生酸枣幼苗移栽后第80 d(CK1),其叶片细胞膜透性、SOD、POD、CAT活性和脯氨酸含量均显著高于2年生酸枣实生苗(CK)(P<0.05);MDA、可溶性糖、淀粉、蛋白质含量没有达到显著水平(P>0.05)。NaCl胁迫下,浓度为0～200 mmol/L,2年生酸枣移栽苗叶片中细胞膜透性,SOD、POD、CAT活性显著高于2年生酸枣实生苗(CK)(P<0.05);浓度为250、300 mmol/L时,SOD、POD的活性下降,而CAT活性处于稳定状态。随之NaCl浓度的加重,2年生酸枣移栽苗叶片中脯氨酸的含量成倍增加,可溶性糖、可溶性蛋白、淀粉的含量均呈增加趋势。【结论】对于酸枣移栽苗来说,在NaCl浓度为0～200 mmol/L,其叶片中的活性氧清除酶开始启动,解除活性氧的毒害,脯氨酸起着重要的渗透调节作用,因此,在此范围内的酸枣移栽苗受到盐害较轻;而在250～300 mmol/L的NaCl胁迫下,酸枣移栽苗受到的伤害比较高。

[Objective] The purpose of the study is to evaluate salt tolerance of the two-year old transplanted seedlings of wild jujube and provide theoretical basis for the expansion of the planting area in salinization region of Xinjiang.[Method] The two year-old transplanted seedlings of wild jujube were treated with different concentrations of NaCl stress.The changes of the membrane permeability,malondialdehyde content （MDA）,superoxide dismutase （SOD） activity,catalase （CAT） activity,peroxidase （POD） activity and osmotic adjustment contents of leaves were studied.[Result] The two year old seedlings of wild jujube were transplanted after 80 d （CK1）,the membrane permeability,SOD,POD,CAT activity and proline content were significantly higher than those of the two year-old seedlings of wild jujube （CK） （P 〈0.05） ;MDA,soluble sugar,starch and protein content were not significant （P 〉 0.05）.Under 0-200 mmol/L NaCl concentration,SOD,POD,CAT activity in leaves of two year-old transplanted seedlings of wild jujube was significantly higher than those of the two year-old seedlings of wild jujube （CK） （P 〈 0.05） ; But it＇sSOD,POD activity were decreased and CAT activity were in stable state under 250 and 300 mmol/L NaCl concentration.With the increase of NaCl concentration,proline content was doubly increased in the leaves,and soluble sugar,starch and proline content was increased too,but the increase was not so significant.[Conclusion] The two year-old transplanted seedlings of wild jujube,under 0-200 mmol/L NaCl concentration,leaves active oxygen scavenging enzymes were started,and the active oxygen poison was released,which revealed that the proline was an important osmotic adjustment in leaves of two year-old transplanted seedlings of wild jujube.Therefore,the two year-old transplanted seedlings of wild jujube would not been injured or little injured basically under 0-200 mmol/L salt stress,but there were injuries under 250 -300 mmol/L NaCl stress.