Mechanism of plant tolerance to heavy metals enhanced by arbuscular mycorrhizal fungi

Arbuscular mycorrhizae (AM) are the symbionts between AM fungi and plant roots in natural and artificial ecosystems. AM symbionts could decrease the harmful stress from heavy metals and regulate the heavy metals uptake and translocate to their host plants. In order to discover the physiological and molecular mechanism of heavy metals tolerance induced by AM fungi, the function and strategies of AM symbionts were discussed in this paper: 1) the fungal hyphae could immobilize heavy metals and restrict the translocation of heavy metals from roots to shoots; 2) chelating substances could immobilize heavy metals; 3) AM fungi could promote the nutrient acquisition to host plants; 4) AM fungi could regulate the distribution of heavy metals in host plants; 5) AM fungi could influence the antioxidative enzymes system activity and hormones in host plants; 6) the molecular mechanisms that AM fungi regulate heavy metal uptake and translocation. On the basis, this study focused on the possibility of using the system of AMsoil microbiologyhost plant for remediation of heavy metals polluted soil in future.