重金属铅镉短期胁迫对蓬莱蕉生理生化指标的影响

The Effect of Pb and Cd on Physiological and Biochemical Indexes of Monstera Deliciosa Liebm.in the Short-term Conditions

为了探讨蓬莱蕉在Pb、Cd胁迫下的生理变化规律,采用盆栽试验研究土壤重金属Pb、Cd单一及其复合胁迫对蓬莱蕉部分生理指标的影响。结果表明:(1)相同处理水平下,随着处理时间的延长,重金属Pb、Cd单一和复合胁迫下,可溶性糖和可溶性蛋白含量降低,超氧化物歧化酶活性下降,游离脯氨酸、丙二醛含量增加,过氧化氢酶活性升高。在Pb单一胁迫下,总叶绿素含量先升后降,过氧化物酶活性升高;在Cd单一胁迫和Pb、Cd复合胁迫下,总叶绿素含量和过氧化物酶活性先升后降。(2)随着处理浓度的增加,重金属Pb、Cd单一和复合胁迫下,可溶性糖、可溶性蛋白、游离脯氨酸和丙二醛含量增加,过氧化物酶、过氧化氢酶和超氧化物歧化酶活性升高,而总叶绿素含量则表现为下降趋势。说明蓬莱蕉在一定重金属胁迫范围内,可通过增加叶片渗透调节物质和诱导活性氧清除系统,以减少由于胁迫带来的代谢失衡对植株的伤害。

The physiological changes of Monstera deliciosa Liebm.under Pb and Cd stress was explored in order to provide certain theoretical basis for the mechanisms of plants adapting to and resisting heavy metal pollution in the plant growth metabolism process.The physiological effect of lead（Pb）,cadmium（Cd）pollution,and their combined stress on M.deliciosa were studied by apot experiment.The results showed that：（1）At the same processing level,under the stresses of single lead（Pb）,single cadmium（Cd）and their combination,the contents of soluble sugar（SS）and soluble protein（SP）in leaves of Monstera deliciosa Liebm.reduced,and meanwhile the superoxide dismutase（SOD）activity declined,but proline（Pro）content,malondialdehyde（MDA）content and catalase（CAT）activity increased,with the extension of processing time.Under the stress of single Pb,the total chlorophyll（Chl）content increased firstly,and then decreased again,but the peroxidase（POD）activity showed an increasing trend;under the stress of Cd with both single and compound treatment,the total chlorophyll（Chl）content and peroxidase（POD）activity increased firstly,and then decreased.（2）With the increasing heavy metal concentration,under the stress of heavy metals with single and compound treatment,the contents of soluble sugar（SS）,soluble protein（SP）,proline（Pro）and malondialdehyde（MDA）increased,and the activities of peroxidase（POD）,catalase（CAT）and superoxide dismutase（SOD）also increased,but the total chlorophyll（Chl）content presented a falling tendency.In conclusion,under the stress of heavy metals,it is possible for Monstera deliciosa Liebm.to minimize plant damage induced by metabolic imbalance by increasing osmotic adjustment substances and inducing antioxidant defense mechanism.