铅胁迫对蜈蚣草抗氧化酶系统和叶绿素含量的影响

为探明铅对蜈蚣草的胁迫作用,为利用蜈蚣草对重金属的超富集作用修复土壤重金属复合污染提供理论依据,采用水培的方法,在不同浓度Pb2+胁迫下研究了蜈蚣草叶片叶绿素和抗氧化系统的变化情况。结果表明:植株过氧化物酶(POD)和过氧化氢酶(CAT)在受铅胁迫初期,其活性值明显升高,但随着铅胁迫量增加及胁迫时间延长,2种酶的活性则呈下降趋势;蜈蚣草叶片的SOD活性和叶绿素含量则随着Pb2+浓度的增加呈下降趋势。说明,在铅胁迫下,蜈蚣草可通过抗氧化系统的应激反应形成一个应急系统,以清除过多的活性氧,增强植株的抗逆性,减少重金属的毒害作用。

Effects of Lead Stress on Antioxidant Enzyme System and Chlorophyll Content of Pteris vittata

In order to seek the effects of lead stress on P.vittata,water culture method was used to study the transformation of chlorophyll and antioxidant system in P.vittata leaves with the different concentrations of lead.The result showed that the activities of POD and CAT went obviously up at the beginning of leed stress,but they were decreased as the quantity of leed increasing and the time extending.The activity of SOD and Chlorophyll Content of P.vittata showed the downtrend as the quantity of leed increasing.This showed that P.vittata could form an emergency system through emergency reaction of antioxidant system to clean up the overmuch active oxygen,strengthen the antireversion force of plants and reduce the toxic action of heavy metal under the leed stress.