Rhizophagus irregularis

Rhizophagus irregularis (previously known as "Glomus intraradices") is an arbuscular mycorrhizal fungus used as a soil inoculant in agriculture and horticulture. In addition, it is one of the best mycorrhizal varieties of fungi available to mycoforestry, but as it does not produce fruiting bodies it "has virtually no market value as an edible or medicinal mushroom"
"Rhizophagus irregularis" is also commonly used in scientific studies of the effects of arbuscular mycorrhizal fungi on plant and soil improvement.
Until 2001, the species was known and widely marketed as "Glomus intraradices", but molecular analysis of ribosomal DNA led to the reclassification of all arbuscular fungi from Zygomycota phylum to the Glomeromycota phylum.
Description.
Identification.
"Rhizophagus irregularis" colonization peaks earlier than many of the other fungi in the Glomus genus. There tends to be extensive hyphal networking and intense intraradical spores associated with older roots of host plants.
At times the spores are densely clustered or patchily distributed, depending on the host species. When the spores are heavily clustered, mycorrhizologists and others will tend to mistake "G. intraradices" for "G. fasciculatum".
Reproduction.
Rhizophagus irregularis (previously known as Glomus intraradices) has been found to colonise new plants by means of spores, hyphae or fragments of roots colonized by the fungus 
Ecology and distribution.
Distribution.
"Rhizophagus irregularis" can be found in almost all soils, especially those populated with common host plants and in forests and grasslands.
This is a brief list of some common host plants. Most agricultural crops will benefit from "Rhizophagus irregularis" inoculation. Generally host plants must be vascular plants, but not always.
Conservation and status.
"Rhizophagus irregularis" is not in danger of becoming extinct; however, most damage is caused by chemicals and tillage.
Relevance.
"R. irregularis" is known to colonize nearly all important commercial crops including rice, corn, soybean, wheat, cannabis, hemp, and alfalfa.
In numerous scientific studies "G. intraradices" has been shown to increase phosphorus uptake in multiple plants as well as improve soil aggregation due to hyphae.
Because of these qualities, "G. intraradices" is commonly found in mycorrhizal based fertilizers.
In a recent study, "G. intraradices" was found to be the only arbuscular mycorrhizal fungi that was able to control nutrient uptake amounts by individual hyphae depending on differing phosphorus levels in the surrounding soil.