Mycorrhizas and nutrient cycling in ecosystems – a journey towards relevance?
Article first published online: 3 MAR 2003
Volume 157, Issue 3, pages 475–492, March 2003
How to Cite
Read, D. J. and Perez-Moreno, J. (2003), Mycorrhizas and nutrient cycling in ecosystems – a journey towards relevance?. New Phytologist, 157: 475–492. doi: 10.1046/j.1469-8137.2003.00704.x
- Issue published online: 3 MAR 2003
- Article first published online: 3 MAR 2003
- Received: 3 September 2002 Accepted: 9 December 2002
- ericoid mycorrhiza;
- arbuscular mycorrhiza;
- nitrogen nutrition;
- phosphorus nutrition;
Progress towards understanding the extent to which mycorrhizal fungi are involved in the mobilization of nitrogen (N) and phosphorus (P) from natural substrates is reviewed here. While mycorrhiza research has emphasized the role of the symbiosis in facilitation of capture of these nutrients in ionic form, attention has shifted since the mid-1980s to analysing the mycorrhizal fungal abilities to release N and P from the detrital materials of microbial faunal and plant origins, which are the primary sources of these elements in terrestrial ecosystems. Ericoid, and some ectomycorrhizal fungi have the potential to be directly involved in attack both on structural polymers, which may render nutrients inaccessible, and in mobilization of N and P from the organic polymers in which they are sequestered. The advantages to the plant of achieving intervention in the microbial mobilization–immobilization cycles are stressed. While the new approaches may initially lack the precision achieved in studies of readily characterized ionic forms of N and P, they do provide insights of greater ecological relevance. The results support the hypothesis that selection has favoured ericoid and ectomycorrhizal systems with well developed saprotrophic capabilities in those ecosystems characterized by retention of N and P as organic complexes in the soil. The need for further investigation of the abilities of arbuscular mycorrhizal fungi to intervene in nutrient mobilization processes is stressed.