不同浓度Na_(2)CO_(3)胁迫处理对科罗拉多蓝杉生理特性的影响

Effects of Na_(2)CO_(3) Stress on Physiological Characteristics of Picea pungens var.glauca

为研究碱性盐胁迫对科罗拉多蓝杉生理特性的影响,旨在为其在盐碱地上的栽植提供科学指导与理论依据,采用盆栽梯度浓度盐水补给法,对一年生蓝杉进行不同浓度的Na_(2)CO_(3)溶液[浓度分别为0(CK),3‰,6‰,9‰]胁迫处理,分别在第10天、第20天、第30天、第40天测定蓝杉叶中叶绿素、可溶性糖、游离脯氨酸、MDA、相对电导率以及SOD和POD等生理指标。结果表明:蓝杉叶中叶绿素a及叶绿素b的含量随着Na_(2)CO_(3)浓度的升高而降低,当胁迫时间超过10d,且Na_(2)CO_(3)浓度在大于3‰时,其含量显著降低。当胁迫时间超过20d,且Na_(2)CO_(3)浓度为9‰时,可溶性糖含量显著升高。游离脯氨酸含量随着Na_(2)CO_(3)浓度的升高而升高,当浓度大于3‰时,其含量开始显著升高。相对电导率在在Na_(2)CO_(3)浓度超过9‰时,从第20天开始显著升高。SOD与POD活力都随着Na_(2)CO_(3)浓度的升高而降低,而MDA含量随着Na_(2)CO_(3)浓度的升高而升高,当Na_(2)CO_(3)浓度超过3‰时,三者含量出现显著性变化。这说明蓝杉正常生长的碱性盐阈值为3‰,过高盐浓度会损害植株的的生长发育。

The aim of this study was to demonstrated the effects of saline-alkali stress on physiological characteristics of Picea pungens var.glauca,then provided scientific guidance and theoretical basis for its reasonable planting.In this study,one-year-old trees were treated with different concentrations of Na_(2)CO_(3) solution stress by the pot gradient concentration water supply method.The concentrations were performed to 0(CK),3‰,6‰and 9‰respectively.On the 10th,20th,30th and 40th day,the physiological characteristics,including the contents of chlorophyll,soluble sugar,free proline,MDA,relative conductivity,and activities of SOD and POD,in the leaves were measured.The results showed that the content of chlorophyll a and b in leaves decreased with the increase of Na_(2)CO_(3) concentration.When the stress time exceeded 10 days and the Na_(2)CO_(3) concentration was greater than 3‰,the content of chlorophyll a and b decreased significantly.When the stress time exceeded 20 days,and the Na_(2)CO_(3) concentration was 9‰,the soluble sugar content increaseed significantly.The content of free proline increased with the increase of Na_(2)CO_(3) concentration.When the concentration was greater than 3‰,their content started to increase significantly.When the concentration of Na_(2)CO_(3) exceeded 9‰,the relative conductivity increased significantly from the 20th day.The activities of SOD and POD both decreased with the increase of Na_(2)CO_(3) concentration,while the content of MDA increased with the increase of Na_(2)CO_(3) concentration.When the concentration of Na_(2)CO_(3) exceeded 3‰,the content of the SOD,POD,and MDA changes significantly.This suggested that the threshold value of alkaline salt for normal growth in the Picea pungens var.glauca planting is 3‰;otherwise,the growth and development of plants will be damaged.