Logo of pnasPNASInfo for AuthorsSubscriptionsAboutThis Article
Proc Natl Acad Sci U S A. 1980 Apr; 77(4): 2113–2118.
PMCID: PMC348662

Ecological and evolutionary significance of mycorrhizal symbioses in vascular plants (A Review)


Mycorrhizae, the symbioses between fungi and plant roots, are nearly universal in terrestrial plants and can be classified into two major types: endomycorrhizae and ectomycorrhizae. About four-fifths of all land plants form endomycorrhizae, whereas several groups of trees and shrubs, notably Pinaceae, some Cupressaceae, Fagaceae, Betulaceae, Salicaceae, Dipterocarpaceae, and most Myrtaceae form ectomycorrhizae. Among legumes, Papilionoideae and Mimosoideae have endomycorrhizae and usually form bacterial nodules. The members of the third subfamily, Caesalpinioideae, rarely form nodules, and one of the included groups, the two large, pantropical, closely related tribes Amherstieae and Detarieae, regularly form ectomycorrhizae. Nodules and ectomycorrhizae may well be alternative means of supplying organic nitrogen to the plants that form them.

Those plants having endomycorrhizae usually occur in forests of high species richness, whereas those with ectomycorrhizae usually occur in forests of low species richness. The roots of ectomycorrhizal trees, however, support a large species richness of fungal symbionts, probably amounting to more than 5000 species worldwide, whereas those of endomycorrhizal trees have low fungal species richness, with only about 30 species of fungi known to be involved worldwide. Ectomycorrhizal forests are generally temperate or occur on infertile soils in the tropics. They apparently have expanded in a series of ecologically important events through the course of time from the Middle Cretaceous onward at the expense of endomycorrhizal forests.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.3M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Pirozynski KA, Malloch DW. The origin of land plants: a matter of mycotrophism. Biosystems. 1975 Mar;6(3):153–164. [PubMed]
  • Ruehle JL, Marx DH. Fiber, food, fuel, and fungal symbionts. Science. 1979 Oct 26;206(4417):419–422. [PubMed]
  • Whittaker RH, Levin SA. The role of mosaic phenomena in natural communities. Theor Popul Biol. 1977 Oct;12(2):117–139. [PubMed]
  • Regal PJ. Ecology and evolution of flowering plant dominance. Science. 1977 May 6;196(4290):622–629. [PubMed]
  • Heinrich B, Raven PH. Energetics and pollination ecology. Science. 1972 May 12;176(4035):597–602. [PubMed]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences


Save items

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...


  • PubMed
    PubMed citations for these articles

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...