Write a short on Mycorrhizae.

A mycorrhiza is asymbiotic association composed of a fungus and roots of a vascular plant In a mycorrhizal association, the fungus colonizes the host plant's roots, either intracellularly as in arbuscular mycorrhizal fungi (AMF or AM), or extracellularly as in ectomycorrhizal fungi. They are an important component of soil life and soil chemistry. The association is generally mutualistic, but occasionally weakly pathogenic     Many conspicuous fungi such as the fly agaric (upper left) form ectomycorrhiza (u. right) with tree rootlets. Arbuscular mycorrhiza (lower left) is very common in plants, including crop species such as wheat (l. right).