ABSTRACT
Mycorrhizas are mutualistic symbiotic associations between plant roots and fungi (1). Various categories of mycorrhizas are recognized based on the morphological and anatomical modifications of the root system and the fungal groups involved (2). The two most prevalent categories of mycorrhizas, ectomycorrhizas (ECMs) and arbuscular mycorrhizas (AMs), are found in approximately 90% of all vascular plants, making mycorrhizas the most prevalent symbiosis on Earth. ECMs are formed by the interaction of fungi belonging to the Basidiomycotina and Ascomycotina with roots of mostly tree species. The morphology of ECMs can be determined easily. Structurally, they are characterized by the formation of a mantle or sheath of fungal hyphae enveloping lateral roots and Hartig net hyphae that penetrate between root epidermal and cortical cells (2). Figure 1(1) illustrates the basic features of an ectomycorrhiza. Extraradical hyphae extend from the surface of the mantle into the soil and are involved in absorbing nutrients and water that are transported to roots. Rhizomorphs, sclerotia, and sexual reproductive bodies may develop in the extraradical mycelium.
