土壤铅、镉胁迫对4种绿化植物生长、生理及积累特性的影响

Effects of Soil Pb,Cd Stress on the Growth,Physiological and Accumulating Characteristics of Four Ornamental Trees

研究不同处理浓度的Pb、Cd单一胁迫对4种绿化植物(小叶丁香、红瑞木、辽东水蜡、杞柳)生长、生理及积累特性的影响。结果表明:随重金属处理浓度的增加,4种绿化植物株高和地径的增加都受到抑制,浓度越高,抑制越明显;4种植物叶片内游离脯氨酸含量对不同处理水平的重金属响应不同;MDA含量均随胁迫浓度的增加而增大;SOD活性除红瑞木(Cd=1.00mg/kg,达到最大值),其余均随处理浓度的增加而下降;小叶丁香和辽东水蜡POD活性随处理浓度的增加先升高(Pb=250mg/kg,Cd=1.00mg/kg达到最大值)后降低,红瑞木和杞柳随处理浓度的增加而升高。4种绿化植物根部对Pb的积累较强,而叶片对Cd的积累能力大于其对Pb的富集能力。综合各个指标变化情况来看,4种绿化植物对重金属Pb、Cd的抗性排序为红瑞木>杞柳>辽东水蜡>小叶丁香。

The effect of growth,physiological and accumulating characteristics of four trees（Sytinga microphylla,Swida alba,Ligustrum obtusifolium,Salix integra）on Pb,Cd single stress under different treatment concentration was studied by apot experiment.The results showed that with the increase of the treatment concentration of different heavy metals,growth of plant height and diameter were inhibited.The response of free proline content in four trees was different to the treatment of heavy metals concentrations.The content of MDA increased with increasing concentration of heavy metals.The activity of SOD decreased with increasing concentration of heavy metals expect Swida alba（when Cd=1.00mg/kg,it reached maximum）.The activity of POD of Sytinga microphylla and Ligustrum obtusifoliumincreased first（when Pb=250mg/kg,Cd= 1.00mg/kg,it reached maximum）then decreased with increasing concentration of heavy metals.The activity of POD of Swida alba and Salix integra increased with increasing concentration of heavy metals.The Pb accumulation in the roots of four trees were higher,the Cd accumulation in the leaves of four trees were higher.Based on the overall consideration of changes of the indicators,the sequence of tolerance to the heavy metal Pb,Cd was Swida alba Salix integra Ligustrum obtusifolium Sytinga microphylla.