根生长法测定柳树对重金属的耐性研究（摘要）

[目的]探讨柳树对单一或复合重金属的耐性大小,为木本植物修复重金属污染土壤提供理论依据。[方法]采用根生长法研究重金属Cu^2＋、Pb^2＋、Zn^2＋及3者混合液对柳树枝条不定根生长的影响。调查项目包括柳树枝条不定根的数目及长度,并由此计算生根率、抑制率和耐性指数。[结果]不同浓度的重金属溶液对柳树枝条不定根的生长存在显著影响。当Cu^2＋浓度高于15mg/L、混合溶液浓度高于20mg/L、Zn^2＋浓度高于30mg/L时,柳树枝条均无不定根生成;溶液浓度达到40mg/L时,只有Pb^2＋处理组能长出不定根;随着溶液浓度的升高,柳树枝条不定根的数目逐渐下降;浓度为5mg/L的Zn^2＋处理组柳树枝条不定根数目最多。其他浓度中,Pb^2＋处理组不定根数目最多、根长及平均根长最长、生根率最高。[结论]柳树枝条对Pb^2＋的耐受性最强,对Cu^2＋的耐受性最弱。柳树对3种重金属及3者混合液的耐受性大小依次为Pb^2＋〉Zn^2＋〉Cu^2＋＋Pb^2＋＋Zn^2＋〉Cu^2＋。

Tolerance of Salix matsudana to Heavy Metals Determined by Root Elongation Method

[Objective]The research aimed to discuss the tolerance of Salix matsudana to single or compound heavy metals and provide theoretical basis for renovating polluted soil by heavy metals with woody plants.[Method]Using root elongation method,the effects of heavy metal Cu^2＋,Pb^2＋,Zn^2＋ and their mixed solution on the adventitious roots growth of S.matsudana cuttings were studied.[Result]The adventitious roots growth of S.matsudana cuttings was obviously affected by different concentrations of heavy metals solution.Adventitious roots of S.matsudana cuttings could not grow while the concentration of Cu^2＋ was higher than 15 mg/L,the mixture solution concentration was higher than 20 mg/L and Zn^2＋ concentration was higher than 30 mg/L.When the solution concentration reached 40 mg/L,adventitious roots of S.matsudana cuttings could grow only in Pb^2＋ treatment group.With the increasing of the solution concentration,the number of adventitious roots of S.matsudana cuttings gradually decreased.In 5 mg/L Zn^2＋ treatment group,the number of adventitious roots of S.matsudana cuttings was the most,the longest root length and average root length were the longest and the rooting rate was the highest.[Conclusion]The tolerance of S.matsudana to Pb^2＋ was strongest and its tolerance to Cu^2＋ was the weakest.The tolerance order of S.matsudana to three kinds of heavy metals and their mixed solution was as following：Pb^2＋〉Zn^2＋〉Cu^2＋＋Pb^2＋＋Zn^2＋〉Cu^2＋.