The Role of Mycorrhizae in Enhancing Plant Resilience to Heavy Metal Stress: A Focus on Arbuscular Mycorrhizal Fungi (AMF) and Their Interaction with Soil Microbiomes
Arbuscular Mycorrhizal Fungi (AMF) play a critical role in enhancing plant resilience to heavy metal stress by improving nutrient uptake, particularly phosphorus, while activating key antioxidant defense mechanisms such as superoxide dismutase (SOD) and catalase (CAT), thereby mitigating oxidative damage caused by reactive oxygen species (ROS). AMF interact synergistically with Plant Growth-Promoting Rhizobacteria (PGPR), such as Bacillus and Pseudomonas, to reduce the bioavailability of toxic heavy metals like cadmium (Cd), lead (Pb), and zinc (Zn) through immobilization, chelation, and pH modulation in the rhizosphere. These microorganisms promote root colonization, enhance nutrient cycling, and improve soil structure through the secretion of glomalin, further supporting plant growth and phytoremediation efforts. AMF-based bioinoculants represent a promising sustainable agricultural strategy to remediate contaminated soils and enhance crop productivity in metal-stressed environments. However, challenges remain in understanding the species-specific responses of AMF and optimizing their application under diverse environmental conditions, requiring further research into the molecular mechanisms governing AMF-plant-microbiome interactions.
Keywords: AMF, PGPR, heavy metal stress, phytoremediation, bioinoculants
