【摘要】 以九里香为试材,采用盆栽试验方法,研究了250、500、1 000、1 500、3 000 mg·kg^-1铅（Pb）胁迫下九里香对Pb的吸收和九里香生物量,叶绿素含量、脯氨酸（Pro）含量、超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、过氧化物酶（POD）活性的变化,以期为在大生物量植物中筛选Pb污染的修复植物提供参考依据。结果表明:当土壤Pb浓度为250 mg·kg^-1时,九里香根、茎、叶的生物量达到峰值,叶绿素含量、Pro含量、SOD和CAT活性也显著高于对照;超过这一浓度后,这些指标开始下降,在3 000 mg·kg^-1的土壤Pb浓度胁迫下,生物量、叶绿素含量、Pro含量降到最低,与对照相比差异不显著,SOD、CAT活性在高浓度Pb胁迫下虽然出现不同程度的降低,但均高于对照。POD活性则表现为随着Pb处理浓度的增加而上升。九里香根、茎、叶对Pb的积累随着土壤Pb浓度的增加而增大,根是Pb的主要吸收部位。在不同Pb浓度处理下,植株转移系数均小于0.5,而耐性指数为0.79～1.22。以上结果表明,九里香具有较强的Pb耐性,能在高浓度的Pb污染土壤中生存,但并非Pb富集植物,可作为Pb污染地区的先锋树种用于植被重建和生态恢复。更多还原

【Abstract】 Taking Murraya exotica L. as material,a pot-experiment was conducted to investigate its biomass,physiological index and Pb accumulation characteristics under different Pb concentration(250,500,1 000,1 500,3 000 mg·kg^-1).The results demonstrated that when soil Pb concentration was 250 mg·kg^-1,the biomass of roots,stems and leaves of Murraya exotica L. reached the peak value and the content of chlorophyll and Pro as well as the activities of SOD and CAT became significantly higher than those of the control group.When soil Pb concentration was over 250 mg·kg^-1,all these indexes decreased respectively.When soil Pb concentration was 3 000 mg·kg^-1,the biomass,the content of chlorophyll and Pro were the smallest,while the data varieties were not apparent.Nevertheless,in high Pb concentrations,the activities of SOD and CAT decreased in different degrees,but the data were still higher than those of the control group.On the other hand,the activities of POD raised with the increase of Pb concentration.Pb accumulation in roots,stems and leaves of Murraya exotica L.increased with the increase of Pb concentration in soil.The roots was the main part of Pb absorption.Under the series of Pb concentration treatments,the transport coefficient was less than 0.5 and the tolerance index was between 0.79-1.22.The results indicated that Murraya exotica L.had a strong Pb tolerance and could survive in the soil polluted by high Pb concentration.But it was not Pb hyperaccumulation plant.It could be used to recover the vegetation and restore damaged ecosystem.更多还原