摘要
在金属污染物进入体内之前将其有效性和毒性降低是植物的主要抗金属机制之一 .根系是金属等土壤污染物进入植物的门户 ,它能分泌有机酸、氨基酸、糖、生长物质等根分泌物到根际环境 .根分泌物在植物吸收金属的过程中影响很大 ,它们可以通过改变根际环境的 pH、Eh等物理、化学性质而影响根系对金属的吸收 ;通过螯合、络合、沉淀等作用将金属污染物滞留于根外 ;通过改变根际微生物的组成、活性和分泌作用而改变根际环境中金属的数量和活度等 .本文就国内外根分泌物与植物的金属抗性研究状况作一归纳和评述 ,并在此基础上提出存在的问题和今后研究的重点。
Reducing the availability and toxicity of metal pollutants before they enter plant body is one of the main mechanisms of plant resistance to metals.Root system is the first entrance of metal pollutants from soil into plant.It can excrete organic acids,amino acids,sugars,growth substances etc.into rhizosphere.Root excretion affects the metal absorption by plant through changing the physical and chemical characters(such as pH,Eh)of rhizosphere.The metal pollutants are detained outside the roots by chelation,complexation and disposition with root exudates.The quantity and activity of metals in rhizosphere are changed by root exudates through changing the composition,activity and excretion of microbes there.After reviewing the research advances on root excretion and plant resistance to metals,the authors pointed out the existing problems and the major topics and significance of further research.
出处
《应用生态学报》
CAS
CSCD
2000年第2期315-320,共6页
Chinese Journal of Applied Ecology
基金
国家自然科学基金资助项目 !(39360020
39760022
39970142)
