Interactions between Arbuscular Mycorrhizal Fungi and plants communities. Some examples from arid ecosystems

Abstract

Martinez, L.B., Pugnaire, F.I. (2009). Interactions between Arbuscular Mycorrhizal Fungi and plants communities. Some examples from arid ecosystems. Ecosistemas 18(2):44-54.

Interactions between arbuscular mycorrhizal fungi and plants communities. Some examples from arid ecosystems. Most studies of terrestrial ecosystems have been focused on processes of facilitation and competition between plants as determinants of the structure of terrestrial ecosystems. Nevertheless, belowground organisms and their interactions with plant communities have been highlighted in the last years as essential players in the interactions between plant species in terrestrial ecosystems. Arbuscular mycorrhizal fungi (AMF) stand out among soil organisms because of their abundance and relevance. Mycorrhizae are symbiotic associations between mycorrhizal fungi and plant roots, establishing a bidirectional exchange of nutrients and carbon. However, changes in environmental factors may modulate this interaction becoming a commensalism or even a parasitism. AMF have an external mycelium which inter-communicates some of the plants from the plant community, creating a complex net of relationships that has a decisive influence on the diversity and composition of plant communities. In some cases, AMF might even determine the success or failure of invasion by exotic plants. In harsh environments, such as arid and semiarid ecosystems, these fungi are particularly important because they improve the establishment of some seedlings and help them to overcome adverse conditions by increasing the uptake of nutrients and water. With to the application of molecular analysis tools, our understanding of AMF ecology has improved considerably, revealing the great diversity of species and the factors influencing their spatial distribution. The specific diversity of AMF is associated with a high functional diversity that largely determines the interactions between communities of AMF and plants.