Metal tolerant mycorrhizal plants: A review from the perspective on industrial waste in temperate region

Abstract

The chapter summarizes research carried out on the role of mycorrhizal fungi in phytoremediation of heavy-metal-rich wastes in temperate regions. Symbiotic fungi are an important component of soil microbiota, especially under harsh conditions. Properly developed mutual symbiosis enhances the survival of plants in polluted areas by improving nutrient acquisition and water relations. In addition, mycorrhizal fungi were found to play an important role in heavy metal detoxification and the establishment of vegetation in strongly polluted areas. Fungal strains isolated from old zinc wastes also decrease heavy metal uptake by plants growing on metal rich substrata, limiting the risk of increasing the levels-of these elements in the food chain. The effectiveness of the bioremediation techniques depends on the appropriate selection of both the plant and the fungal partners. Plants conventionally introduced in such places disappear relatively soon, while those appearing during natural succession are better adapted to harsh conditions. Symbiotic partners selected on the basis of such research are often the best choice for future phytoremediation technologies. Moreover, mycorrhizas of different types are also helpful in substratum toxicity monitoring. Further improvements can be obtained by optimization of diverse microbiota including various groups of rhizospheric bacteria and shoot endophytes.