Pollution of the biosphere with heavy metals poses a major environmental and human health problem. Phytoremediation methods
(including phytoextraction, rhizofiltration and
phytostabilization) have recently attracted much attention. Mycorrhizal infection exists in most heavy-metal-polluted environment, suggesting that
heavy metal tolerance or other beneficial effects are conferred by the mycorrhizal symbiosis. Mycorrhizae can bind metals and limit their translocation to shoot, and provide a new way for phytostabilization and protect plants against the toxicity of heavy metals. Ectomycorrhizal and endomycorrhizal fungi can accumulate high metal contents in their fruiting bodies, and that metal accumulation varies between species and strains. Mycorrhizal fungi tolerate the toxicity of heavy metals by ion exchange, formation of complexes, precipitation or crystallization. Heavy metals content in the fruitbodies of mycorrhizal fungi, propagule density and infectivity can be used as bioindicators of soil contamination.