不同生态型植物对重金属的积累及耐性研究进展

植物修复是目前治理土壤重金属污染最重要的方法之一，选择合适的植物是植物修复的关键.分类学上种的概念在生态恢复应用上是不充分的，必须从生态型水平上去探讨.不同生态型的同种植物在积累和忍耐重金属方面通常有很大的区别.它们对外源金属的浓度、离子供应形态及金属离子间的相互作用表现出不同的响应特征，富集能力上的差别主要源于不同生态型在金属转运体、解毒机理和遗传特性的不同；金属耐性上的差别主要是由于遗传机制、酶系统、对重金属的避性及区域化不同造成的，植物螯合肽(PC)不是耐性差异的主要因素.不同生态型植物是研究超富集、金属耐性和金属积累机理的理想材料.

A Review of Heavy Metal Accumulation and Tolerance by Plants of Different Ecotype

Phytoremediation is now regarded as one of the most important techniques to clean soil of heavy metal contamination.It is a key for phytoremediation to select proper plants.Concept of species in taxonomy is not enough in identifying plants for ecological restoration.Rather,consideration must be taken at the level of ecotype.Plants of different ecotype often have large difference in accumulating and tolerating heavy metal,although they are classified as the same species in taxonomy.They could respond differently to variation of concentration,ion form,and interaction of heavy metals.Difference in accumulating heavy metals is mainly attributed to the difference of heavy metal transporter,detoxication and genetics.Difference in enduring heavy metals is due to the difference in genetics,enzyme system and sequestration in cell of different ecotypic plants,while phytochelatins (PC) is not a key factor.Plants of different ecotype are ideal materials in study of hyperaccumulation,toleration and detoxication of heavy metals.This paper introduces the concept,origination and classification of ecotype.It also reviews research progress in heavy metal accumulation and toleration of different ecotypic plants.