Taylor, Andy F. S. Macaulay Institute, University of Aberdeen, Aberdeen, United Kingdom.
- Interactions with other soil organisms
- Facultative fungi
- Links to Primary Literature
- Additional Readings
An obligate association formed between the roots of many plant species, especially trees, and a diverse range of soil fungi. The fungi and the finest, terminal root tips interact to form joint organs called ectomycorrhizas (Fig. 1). In ectomycorrhizal (ECM) symbiosis, the fungi exchange soil-derived nutrients for carbohydrates from the host plant. Nutrient uptake into the host is enhanced by the efficient spatial exploitation of the soil by the fungi and via access to nutrients, particularly organic sources, which would not be directly available to the plant. The percentage of root tips converted to ectomycorrhizas is usually close to 100%, which means that the belowground absorptive surfaces of most ECM plants are effectively isolated from the soil environment by a 30–80-micrometers (μm)-wide layer of fungal tissue (the mantle) [Fig. 2]. Nutrients and water taken up by the ECM trees and any carbon that enters the soil environment from the tree roots must pass through this structure. Consequently, by occupying the interface between the soil and the absorptive root surface, the ECM symbiosis can have a considerable influence not only on the nutrition of the host trees but also upon the soil environment in which they grow. See also: Forest soil; Fungi; Mutualism; Mycorrhizae; Root (botany)
The content above is only an excerpt.
for your institution. Subscribe
To learn more about subscribing to AccessScience, or to request a no-risk trial of this award-winning scientific reference for your institution, fill in your information and a member of our Sales Team will contact you as soon as possible.
to your librarian. Recommend
Let your librarian know about the award-winning gateway to the most trustworthy and accurate scientific information.
AccessScience provides the most accurate and trustworthy scientific information available.
Recognized as an award-winning gateway to scientific knowledge, AccessScience is an amazing online resource that contains high-quality reference material written specifically for students. Its dedicated editorial team is led by Sagan Award winner John Rennie. Contributors include more than 9000 highly qualified scientists and 42 Nobel Prize winners.
MORE THAN 8500 articles and Research Reviews covering all major scientific disciplines and encompassing the McGraw-Hill Encyclopedia of Science & Technology and McGraw-Hill Yearbook of Science & Technology
115,000-PLUS definitions from the McGraw-Hill Dictionary of Scientific and Technical Terms
3000 biographies of notable scientific figures
MORE THAN 17,000 downloadable images and animations illustrating key topics
ENGAGING VIDEOS highlighting the life and work of award-winning scientists
SUGGESTIONS FOR FURTHER STUDY and additional readings to guide students to deeper understanding and research
LINKS TO CITABLE LITERATURE help students expand their knowledge using primary sources of information