Plant chemicals to promote rhizoremediation of POP-contaminated brownfields

植物化学品促进受持久性有机污染物污染的棕地的根部修复

• 批准号: 356996-2007
• 负责人: Sylvestre, Michel
• 金额: $ 6.06万
• 依托单位: Institut national de la recherche scientifique
• 依托单位国家: 加拿大
• 项目类别: Strategic Projects Supplemental Competition
• 财政年份: 2007
• 资助国家: 加拿大
• 起止时间: 2007-01-01 至 2008-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=364158
• 关键词: Plant; chemicals; promote; rhizoremediation; POP

Rhizosphere is the zone surrounding plant roots where complex interactions take place between plants, and microorganisms. The bacteria living in association with plant roots are called plant growth promoting rhizobacteria (PGPR). This association is highly beneficial for both organisms. PGPR protect plants against diseases and they produce plant growth stimulators. In return, plants exude compounds that are beneficial for overall activities of PGPR. Exudates contain chemicals that act as signal to promote the root colonization process by PGPR and others such as flavonoids and terpenes that may induce catabolic pathways involved in the degradation of soil organics including persistent pollutants (POPs) such as polychlorinated biphenyls (PCBs). Therefore, rhizoremediation is a process in which plants pump contaminants to the rhizosphere and release chemicals that promote rhizobacterial growth and induce their POP catabolic pathways.  Rhizoremediaton is among the most suitable technology for remediating brownsfields since its cost is 50 to 80% lower than alternatives and it requires a minimum of intervention. The objectives of this proposal are 1- to identify plant root exudates components that induce root colonization traits of rhizobacteria, thus facilitating their implantation and survival in soil; 2- to identify exudates components that induce PCB degradation by PCB-degrading rhizobacteria. These chemicals will be of high commercial value as they should provide an additional tool to assist the phytoremediation processes. The specific objectives will be 1- to screen for natural PGPR from crucifers or legumes exhibiting the dual ability of utilizing phenylpropanoids and degrading POPs; 2- To identify chemicals from plant exudates [crucifers (Arabidopsis thaliana) and legumes (Medicago sativa, alfalfa plant)] that act as effector to induce plant root colonization traits by PGPRs; 3- to evaluate the effect of chemicals from plant root exudates on expression of rhizobacterial PCB degrading genes; 4- To assess the influence of the effectors identified in objective 2 and 3 in microcosm assays.

根际是植物根部周围的区域，在植物和微生物之间发生复杂的相互作用。与植物根相关的细菌称为植物生长促进根瘤菌（PGPR）。这种关联对这两种生物都非常有益。 PGPR保护植物免受疾病的侵害，并产生植物生长刺激剂。作为回报，植物获得了对PGPR整体活动有益的化合物。渗出物包含在PGPR以及其他其他可能诱导参与土壤组织降解的分解代谢途径（包括持久污染物（POP），例如多氯联苯（PCB））的分解代谢途径的化学物质。因此，根茎修复是一个过程，在这种过程中，植物将污染物泵入根际，并释放促进根茎生长并诱导其流行分解代谢途径的化学物质。 Rhizoremediaton是补救布朗斯菲尔德（Brownsfields）的最合适的技术之一，因为其成本比替代品低50至80％，并且需要最少的干预措施。该提案的目标是1-识别植物根渗出量的成分，这些成分诱导根瘤菌的根部定植特征，从而支持其植入和在土壤中的生存； 2-鉴定渗出液通过PCB降解根瘤菌诱导PCB降解的组件。这些化学品将具有很高的商业价值，因为它们应该提供额外的工具来协助植物修复过程。特定的目标将是1-筛选自然PGPR的crucifer或豆类，表现出使用苯基丙烷和降解流行的双重能力的豆类。 2-从植物渗出剂（十字花序（拟南芥）和豆类（Medicago sativa，苜蓿植物）中鉴定化学物质，它们是PGPRS诱导植物根菌落特征的效应因子； 3-评估植物根系化学物质对根瘤菌PC​​B降解基因表达的影响； 4-评估目标2和3中微观测定中鉴定的效果的影响。