Functioning Mechanisms of Ectomycorrhizal Fungi and Ectomycorrhiza Associated with Plant in the Tolerance to Heavy Metal Toxicity

Abstract

Ectomycorrhizal fungus (ECMF) is one of the important plant symbiotic fungi. Their functions in enhancing the tolerance of plants to heavy metal toxicity have been widely recognized and applied. The function mechanisms of ECMF of enhancing the tolerances of plants to heavy metal toxicity have been paid much attention. However, many previous reviews have not distinguished the effects and mechanisms on the tolerance to heavy metal toxicity between ECMF and ECMF mycorrhizae symbionts. We reviewed the response mechanisms of pure cultured ectomycorrhizal fungi under heavy metal stress in vitro, the anatomical mechanisms, the physiological mechanisms, the molecular regulation mechanisms of ectomycorrhiza tolerance to heavy metal toxicity and the enhancement of plant tolerance to heavy metal. It will shed the light on the enhancement mechanism of ECMF in the plant tolerance to heavy metal. Further research directions on the application of ectomycorrhizal fungi in the remediation of contaminated sites have been indicated.