铜、水分胁迫下金属型植物海洲香薷水分代谢的变化

Water Metabolism Changes of Metallophyte-Elsholtzia haichowensis Treated with Copper and Water Stress

金属型植物生长土壤重金属含量高,同时保水性和持水能力差,易造成重金属和干旱双重胁迫。据此,本项目选用铜污染区(CS)和非污染区海洲香薷(NCS)为试材,以水培方法构成Cu、水分胁迫,研究金属型植物蒸腾速率(Tr)、叶片水分利用效率(WUE)以及叶片相对含水量(RWC)等的变化。结果表明,与对照相比,Cu、水分胁迫以及Cu+水分胁迫下,NCS的Tr明显下降,WUE明显提高,RWC和根自然含水量(NWC)下降或明显下降。不同的是,对CS而言,其Tr在Cu胁迫下明显上升,在其它处理下明显下降;其WUE在水分胁迫下明显增加,在其它处理下无明显变化;RWC和NWC下降或明显下降;尽管胁迫下CS和NCS的Tr和RWC均下降,但是下降的幅度有较大差别。总之,在铜和干旱胁迫下,不同来源金属型植物水分代谢存在明显差异,其结果可为尾矿库复垦以及矿山生态恢复提供科学依据。

The heavy metal content is high in soil where metallophytes vegetate and its water reten-tion and moisture holding capacity is poor simultaneously. Accordingly, the heavy metal stress and the drought stress easily occur at the same time. In the experiment, hydroponic method formed Cu and water stress,Elsholtzia haichowensis from the Cu-contaminated （CS） and non-contaminated soil （NCS） was used as test materials, the transpiration rate （ Tr）, leaf water use efficiency （WUE） , rel- ative water content （RWC） in leaf and natural water content （NWC） in root was comparatively re- searched. The results claimed that under the stress of Cu, drought and Cu ＋ drought,for NCS ,Tr sig- nificantly decreased, WUE dramatically increased, RWC and NWC declined or significantly de-clined. For CS, compared with control, Tr significantly increased under Cu stress and significantly de-creased under the stress of drought and Cu ＋ and slightly changed under other stresses, drought, WUE dramatically increased under water stress RWC and NWC declined or significantly declined. In short, significant differences in water metabolism occurred between contaminated and non-contamina- ted metallophytes. This could provide scientific evidence to reclamation of tailings reservoirs and eco-logical restoration of metal mine.