Pb,Zn对超富集植物(小鳞苔草)抗氧化酶活性的影响

通过人工气候箱盆栽实验,研究Pb,Zn及其复合胁迫对小鳞苔草(Carex gentilisFranch.)根和叶中SOD,POD及CAT活性的影响。结果表明:叶片SOD活性随Pb和Zn浓度增加均呈缓慢上升趋势,根部SOD则表现为有升有降的过程,Pb Zn复合处理可提高根部和叶片SOD活性,最高分别为201.8 U/gFW和233.1U/gFW。根部POD活性随Pb,Zn浓度增加均出现不同程度提高,但叶片POD活性呈有升有降的过程;根部和叶片POD在Pb Zn复合处理中活性增幅明显,最高分别为对照的7.47倍和1.49倍。根部和叶片中CAT在Pb,Zn及其复合处理中活性均受到不同程度的抑制。方差分析显示,Pb对根部3种酶活性影响显著;Zn对叶片POD活性影响显著;Pb Zn互作对植株体内POD和根部SOD影响极显著。经综合分析,小鳞苔草在Pb,Zn及其复合胁迫条件下,SOD和POD起主要作用,并具有耐Pb高浓度胁迫的抗氧化酶活性调控能力,可望在中国西部铅锌复合污染区植物修复中提供一种新资源。

Influence of Pb,Zn on Activity of SOD,POD and CAT Within Roots and Leaves of Hyperaccumulator(Carex gentiles Franch.)

In this paper,the relationship between Zn,Pb and the activity of the POD,SOD and CAT enzymes within the roots and leaves of Carex gentiles Franch.was examined.This was done through potted plant experiments carried out in the diurnal growth incubator.The results demonstrate a greater amount of SOD activity with increasing amounts of Zn and Pb within the leaves of the plant.In the roots,however,SOD activity fluctuated with increased amounts of Zn and Pb and the combination of them increased the activity of SOD in the roots and leaves.This suggests a positive relationship between SOD activity and zinc concentration.The best activity of SOD were 201.8 U/gFW and 233.1 U/gFW respectively.In the analysis of the POD enzyme,the greatest activity was found in the roots and activity in the leaves was found to fluctuate with the increase of Pb or Zn.With the increase of Pb and Zn,the activity of POD in the roots and leaves increased most.The best activity of POD were contrast group's 7.47 times and 1.49 times.The activity of CAT was found to be inhibited differently by the treat of Pb or Zn,suggesting a negative relationship between CAT activity and zinc concentration.The analysis of variance demonstrate that Pb has the greatest influence on the SOD,POD and CAT within the roots;Zn,on POD in the leaves and the combination of Pb and Zn,on the POD in the body and the SOD in the roots.In general,under the pressure of Pb,Zn or the combination of them,especially under the high pressure of Pb,SOD and POD worked mainly.It is possible that Carex gentiles Franch.is a new source of repairing the forest in west China areas polluted by Pb and Zn.