Unraveling the bioremediation potential of Arbuscular Mycorrhizal Fungi through a bio-inoculation approach

Arbuscular Mycorrhizal Fungi (AMF) even exist in soils polluted by heavy metals and play an important role in improving plant tolerance under stress conditions. A pot culture experiment was carried out to study the effects of AMF inoculation on growth and Cadmium (Cd) uptake through soil enzymatic activities under varying levels of Cd concentrations (3, 6, and 9 mg kg^-1 of soil) in soil by Albizia lebbeck (L.) Benth. seedlings. AMF inoculation significantly improved both shoot and root biomass at a Cd concentration of 3 mg.kg^-1, while a reduction in biomass was observed at 9 mg.kg^-1 concentration of Cd. AMF also enhanced plant growth, with maximum shoot length observed at 3 mgkg^-1 and root length at 9 mgkg^-1. However, AMF spore count decreased while the root colonization rate significantly increased with Cd concentration, leading to a reduction in Cd levels in the rhizosphere of AMF-inoculated seedlings. Soil enzymatic activities like dehydrogenase, acid phosphatase, alkaline phosphatase, and catalase were significantly reduced in non-inoculated seedlings under Cd stress, whereas AMF inoculation improved these enzymatic activities. These results indicate that AMF can alleviate Cd toxicity by decreasing translocation and enhancing the bioaccumulation factor in Albizia lebbeck seedlings. Thus, AMF in combination with Albizia lebbeck offers a promising approach for the phyto-stabilization of Cd-contaminated soils. These findings also highlight the potential of the AMF–Albizia lebbeck interactions system in the bioremediation of Cd-polluted ecosystems.