Which is more common-endomycorrhiza or ectomycorrhiza?

Both endomycorrhiza and ectomycorrhiza have the ability to be mycorrhizal fungi. In endomycorrhiza, the hyphae of the fungus penetrate the outer cells of the plant root and extend into the surrounding soil. In ectomycorrhiza, the hyphae surround but do not penetrate the roots. Endomycorrhiza are much more common than ectomycorrhiza. The fungal component of endomycorrhiza is a zygomycete. While only about thirty species of zygomycetes are known to be involved in endomycorrhizal relationships, the zygomycetes are associated with more than 200,000 species of plants. Basidiomycetes are the most common fungal component of ectomycorrhiza, although some ascomycetes also form ectomycorrhizal relationships. More species of fungi are involved in ectomycorrhiza (at least 5,000), but most are only associated with a single species of plant. Furthermore, the total number of plants involved in ectomycorrhiza is limited to a few thousand.

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