<P> A mycorrhiza (from Greek μυκός mykós, "fungus", and ῥίζα rhiza, "root"; pl . mycorrhizae or mycorrhizas) is a symbiotic association between a fungus and the roots of a vascular host plant . The term mycorrhiza refers to the role of the fungi in the plants' rhizosphere, its root system . Mycorrhizae play important roles in soil biology and soil chemistry . </P> <P> In a mycorrhizal association, the fungus colonizes the host plant's root tissues, either intracellularly as in arbuscular mycorrhizal fungi (AMF or AM), or extracellularly as in ectomycorrhizal fungi . The association is generally mutualistic, but in particular species or in particular circumstances, mycorrhizae may be variously pathogenic in the host plants . </P>

Fungal components usually associated to the roots of pinus belongs to