mycorrhiza

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mycorrhiza

or

mycorhiza

(mī′kə-rī′zə)
n. pl. mycorrhi·zae (-zē) or mycorrhi·zas
The symbiotic association of the mycelium of a fungus with the roots of a plant, as is found in the majority of vascular plants.

my′cor·rhi′zal adj.

mycorrhiza

(Greek myco- fungus, rhiza root) an association between a FUNGUS and the roots of a higher plant. In some cases the fungus breaks down PROTEINS or AMINO ACIDS that are soluble and can be absorbed by the higher plant. In most cases, only nitrogen and phosphorus compounds result from fungal activity. Carbohydrates synthesized by the higher plants are absorbed by the fungus, so the relationship is a form of SYMBIOSIS. Some plants which lack chlorophyll, such as the bird's nest orchid, rely on mycorrhizas for carbohydrates in addition to protein.

There are two types of mycorrhiza: ectomycorrhiza and endomycorrhiza. In an ectomycorrhiza the infecting fungus occurs on the surface of the root and possibly between the cells of the root cortex, but does not penetrate such cells. The root becomes covered by a sheath of fungal tissue and looks different from an uninfected root. It is thicker, has no root hairs or root cap and may be a different colour. Ectomycorrhizae are found mainly on trees, such as oak and pine. In an endomycorrhiza the fungus develops within the cells of the root cortex. Subsequently the root cells digest the fungus leaving only knots of fungal material in the cells. There is usually little difference in the morphology of the root and a sheath of fungal tissue is not normally formed.

References in periodicals archive ?
Mycorrhizal fungus and neem product have the ability to suppress root knot nematodes in different crops including vegetables (Hasan and Khan, 2004); however, no information is available on the combined application of neemex and mycorrhizal fungus for root knot nematode management and their impact on invasion and development in eggplant.
fully recovers biomass and yield of seed cotton after delayed root inoculation with spores of an arbuscular mycorrhizal fungus (Glomus mosseae).
Effect of NPK fertilizers and co-inoculation with phosphate-solubilizing arbuscular mycorrhizal fungus and potassium-mobilizing bacteria on growth, yield, nutrient acquisition, and quality of tobacco (Nicotiana tabacum L.
Inhibition of hyphal growth of a vesicular-arbuscular mycorrhizal fungus in soil containing sodium chloride limits the spread of infection from spores.
Arbuscular mycorrhizal fungus spore associated bacteria affect mycorrhizal colonization, plant growth and potato pathogens.
Phosphodiesterase production and the utilisation of DNA as a phosphorous source by the cricoid mycorrhizal fungus Hymenoscyphus ericae.
Efficacy of arbuscular mycorrhizal fungus (Glomus clarum) in protection of cowpea plants from root rot pathogen Rhizoctonia solani.
Hu J, Lin X, Wang J, Dai J, Cui X, Chen R, Zhang J (2009) Arbuscular mycorrhizal fungus enhances crop yield and P-uptake of maize (Zea mays L.
It is possible that this reduction in colonization by the mycorrhizal fungus lowers the cost of the association for the plant, thereby resulting in an overall neutral effect rather than a negative effect on total plant biomass (Johnson et al.
There were four inoculation treatments:1) Uninoculated control;2) Inoculated with Rhizobium phaseoli ;3) Inoculated with the arbuscular mycorrhizal fungus Glomus fasciculatum (Thaxt) and Gerd and Trappe.