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Toxic pollutants released from various human activities persistently pose significant threats to living organisms, affecting soil fertility, and impacting human health. Among the various remediation approaches, phytoremediation has gained popularity due to its cost-effectiveness and environmentally friendly characteristics. This method involves utilizing plant species to restore polluted soils, emphasizing the intrinsic abilities of plants to remediate contaminated environments. There are various phytoremediation approaches and combinations that have been developed, ranging from phytoextraction to rhizofiltration, each tailored to specific contaminants and environmental conditions. While acknowledging the slow and time-consuming nature of the phytoremediation process and its potential impact on plant growth and development, this review emphasizes the increasing significance of this eco-friendly approach. Moreover, the exploration suggests that leveraging plant-microbe interactions could enhance the efficiency of remediating contaminated areas. Furthermore, understanding the microbial mechanisms involved in phytoremediation is crucial for optimizing remediation outcomes. Microbes play a pivotal role in enhancing plant tolerance to pollutants, facilitating pollutant degradation, and promoting plant growth in contaminated environments. Harnessing the power of microbial communities through bioaugmentation or stimulating indigenous microbial populations can significantly improve phytoremediation efficiency. Emerging omics technologies and the application of CRISPR/Cas9 technology in phytoremediation offer promising avenues for advancing soil remediation efforts. Omics approaches, including genomics, transcriptomics, proteomics, and metabolomics, provide insights into the genetic and molecular mechanisms underlying plant responses to pollutants and can aid in identifying key genes or pathways for enhancing phytoremediation efficiency. Meanwhile, CRISPR/Cas9 technology presents an innovative solution for targeted genome editing in plants, enabling precise modification of genes involved in pollutant uptake, tolerance, and detoxification. By engineering plants with enhanced capabilities for metal sequestration or pollutant degradation, CRISPR/Cas9 holds tremendous potential for accelerating the remediation of contaminated soils. This comprehensive review serves as a valuable resource for environmental practitioners and scientists, providing insights into both traditional and innovative technologies that have the potential to transform soil remediation practices, ultimately contributing to a cleaner and healthier environment.

In response to mounting concerns over heavy metal contamination in soils, this review explores the potential of beneficial soil microorganisms, particularly Plant Growth-Promoting Rhizobacteria (PGPR) and Arbuscular Mycorrhizal Fungi (AMF), as a sustainable solution. These microorganisms play a pivotal role in enhancing plant growth, development, and resilience against heavy metal stress. Effective phytoremediation strategies depend on selecting suitable plant families, including Fabaceae, Brassicaceae, and Poaceae, known for their unique attributes that contribute to heavy metal mitigation. Utilizing beneficial microbes and fostering plant-microbe interactions, commonly termed as 'green technology,' offers a compelling strategy to address heavy metal contamination and promote environmental restoration. AMF species like Glomus and Rhizophagus, and PGPR species belonging to Bacillus and Pseudomonas, significantly enhance phytoremediation. The synergistic interaction between (AMF) and (PGPR) represents a significant advancement, especially in heavy metal-contaminated soils. This interaction amplifies plant growth, enhances resistance to heavy metals, and holds promise for soil restoration and phytoremediation. Future research should focus on elucidating the underlying mechanisms, optimizing synergies, and translating findings into practical applications. Tailored, crop-specific approaches may revolutionize agriculture, considering long-term effects and multi-stress tolerance.

The potential of rhizobacteria in assisting plants used in the phytostabilization or re-vegetation of soils contaminated by heavy metals is gaining interest all around the world. In this context, six rhizobacterial strains isolated from highly heavy metal-contaminated soils situated in abandoned mining sites around the Oujda region (Morocco) were tested with Sulla spinosissima (L.), a native leguminous plant expanding in this area. The strains used were multi-resistant to heavy metals and possessed multiple plant growth-promoting traits. Potential beneficial effects of the strains were also evaluated in planta by measuring various growth and physiological parameters of inoculated Sulla plants grown in sterilized sand. Inoculation with the Rhodococcus qingshengii strain LMR340 boosted plant biomass (39% to 83% increase compared to uninoculated plants), chlorophyll and carotenoid content (up to 29%), and antioxidant enzyme activities (15% to 80% increase). Based on these interesting findings, selected strains were inoculated into plants growing in a heavy metal, multi-polluted, and poor soil. Under these conditions, non-inoculated plants and those inoculated with the strain LMR250 were unable to grow, while the other five bacterial inoculants restored plant growth. The best performing strain, Pseudarthrobacter oxydans LMR291, could be considered as a good biofertilizer and/or biostimulant candidate to be used for promoting the growth of selected plants in re-vegetation and/or phytostabilization programs of degraded and contaminated soils.