The importance of individuals: intraspecific diversity of mycorrhizal plants and fungi in ecosystems


Author for correspondence:
David Johnson
Tel: + 44 1224 273857



II.The potential importance of intraspecific diversity in ecosystems615
III.How diverse are mycorrhizal plant and fungal populations in ecosystems?615
IV.What is the magnitude of physiological variation within species?617
V.The need to understand links between mycorrhizal plant and fungal traits618
VI.How do assemblages of individuals affect ecosystems?619
VII.How do interactions between mycorrhizal plants and fungi affect intraspecific diversity?620
VIII.Can we predict the conditions when intraspecific diversity matters most for regulating ecosystem processes?621
IX.Population genomics: the future to understanding the importance of fungal intraspecific diversity?621
X.Conclusion: the need for a ‘community genetics’ approach in future mycorrhizal symbiosis research624


A key component of biodiversity is the number and abundance of individuals (i.e. genotypes), and yet such intraspecific diversity is rarely considered when investigating the effects of biodiversity of mycorrhizal plants and fungi on ecosystem processes. Within a species, individuals vary considerably in important reproductive and functional attributes, including carbon fixation, mycelial growth and nutrient utilization, but this is driven by both genetic and environmental (including climatic) factors. The interactions between individual plants and mycorrhizal fungi can have important consequences for the maintenance of biodiversity and regulation of resource transfers in ecosystems. There is also emerging evidence that assemblages of genotypes may affect ecosystem processes to a similar extent as assemblages of species. The application of whole-genome sequencing and population genomics to mycorrhizal plants and fungi will be crucial to determine the extent to which individual variation in key functional attributes is genetically based. We argue the need to unravel the importance of the diversity (especially assemblages of different evenness and richness) of individuals of both mycorrhizal plants and fungi, and the need to take a ‘community genetics’ approach to better understand the functional significance of the biodiversity of mycorrhizal symbioses.