最近,增加的地质活动和以人为中心的活动造成了土壤的大量重金属(loid)(HM)污染,对环境产生不利影响,植物,和人类健康。植物修复是一个不断发展的过程,成本效益高,环境友好,采用本地/外来植物物种作为天然净化器的原位技术,从恶化的环境土壤中去除有毒的HM。有趣的是,植物的根瘤菌群是促进植物整体营养的关键,健康,和植物修复。植物生长促进根际细菌(PGPR)产生的某些次生代谢产物通过螯合/动员/螯合/生物吸附/生物积累直接参与HM生物修复,从而改变金属(类)的生物利用度,积累,和植物的易位。此外,PGPR和寄主植物的金属耐受性是成功修复金属(类)污染土壤的另一个关键因素。在可用于HM修复的植物技术中,植物提取/植物积累(HM动员,摄取,以及在不同植物组织中的积累)和植物固存/植物稳定化(土壤中的HM固定)近年来取得了势头。天然金属(类)-超积累植物具有吸收增加的金属(类)水平的潜力,一些这样的物种已经被确定为HM植物修复的潜在候选者。此外,使用基因工程开发具有增强的环境适应性和金属(类)吸收能力的转基因根瘤菌和/或植物菌株可能为PGPR辅助的植物修复技术开辟新的途径。通过使用地理信息系统(GIS)来识别受金属(类)影响的土地,以及正常/转基因(超)累积植物和根际细菌接种剂的适当组合,有可能制定有效的综合植物微生物修复策略,以促进受HM污染的广大地区的清理过程,并最终恢复生态系统健康。
In recent times, increased geogenic and human-centric activities have caused significant heavy metal(loid) (HM) contamination of soil, adversely impacting environmental, plant, and human health. Phytoremediation is an evolving, cost-effective, environment-friendly, in situ technology that employs indigenous/exotic plant species as natural purifiers to remove toxic HM(s) from deteriorated ambient soil. Interestingly, the plant\'s rhizomicrobiome is pivotal in promoting overall plant nutrition, health, and phytoremediation. Certain secondary metabolites produced by plant growth-promoting rhizobacteria (PGPR) directly participate in HM bioremediation through chelation/mobilization/sequestration/bioadsorption/bioaccumulation, thus altering metal(loid) bioavailability for their uptake, accumulation, and translocation by plants. Moreover, the metallotolerance of the PGPR and the host plant is another critical factor for the successful phytoremediation of metal(loid)-polluted soil. Among the phytotechniques available for HM remediation, phytoextraction/phytoaccumulation (HM mobilization, uptake, and accumulation within the different plant tissues) and phytosequestration/phytostabilization (HM immobilization within the soil) have gained momentum in recent years. Natural metal(loid)-hyperaccumulating plants have the potential to assimilate increased levels of metal(loid)s, and several such species have already been identified as potential candidates for HM phytoremediation. Furthermore, the development of
transgenic rhizobacterial and/or plant strains with enhanced environmental adaptability and metal(loid) uptake ability using genetic engineering might open new avenues in PGPR-assisted phytoremediation technologies. With the use of the Geographic Information System (GIS) for identifying metal(loid)-impacted lands and an appropriate combination of normal/
transgenic (hyper)accumulator plant(s) and rhizobacterial inoculant(s), it is possible to develop efficient integrated phytobial remediation strategies in boosting the clean-up process over vast regions of HM-contaminated sites and eventually restore ecosystem health.