Mycorrhiza

From myco... and Greek rhiza – root, - fungus-root, a symbiosis of a fungus's mycelium and the roots of a higher plant. Mycorrhizae are distinguished as ectotrophic, in which the fungus envelops the root, remaining on its surface, and endotrophic, when the fungus penetrates into the root (mycorrhiza of microscopic fungi from the class of imperfect fungi with plants of the orchid and heather famil…

From myco... and Greek rhiza – root, - fungus-root, a symbiosis of a fungus's mycelium and the roots of a higher plant. Mycorrhizae are distinguished as ectotrophic, in which the fungus envelops the root, remaining on its surface, and endotrophic, when the fungus penetrates into the root (mycorrhiza of microscopic fungi from the class of imperfect fungi with plants of the orchid and heather families). The fungal hyphae branch in a treelike manner within the cells or form knob-like swellings.

Mycorrhiza is considered either a mutualistic symbiosis, from which both the fungus and the plant benefit, or a limited parasitism. Mycorrhiza-forming fungi probably decompose some organic soil compounds inaccessible to the plant, aid in the uptake of phosphates and nitrogen compounds, produce substances such as vitamins and growth activators, and themselves use substances (possibly carbohydrates) extracted from the plant root. Seeds of some plants (orchids) are capable of germinating only in the presence of the fungus.