Mycorrhizal symbioses play a prominent role in the biology and ecology of forest trees. They involve soil fungi and roots of trees, which together as a symbiosis provide the fungi with carbohydrates and enhance the uptake of water and nutrients for the trees, and also have a major protective role for the roots (Smith and Read 2008). Forest trees are primarily associated with two types of mycorrhizas: arbuscular mycorrhizas which include fungi from the phylum of Glomeromycota and ectomycorrhizas (EcMs) mainly formed by members of Ascomycota and Basidiomycota. It is currently estimated that 6,000-10,000 plant species (Smith and Read 2008, Brundrett 2009) and 20,000-25,000 fungal species (Rinaldi et al. 2008) are involved in

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