Seasonal Changes in Root Fungi in Japanese Cedar Trees

Jenn Hoskins
22nd March, 2024

Seasonal Changes in Root Fungi in Japanese Cedar Trees

Taxonomic composition of the AMF communities in roots and surrounding soils of Cryptomeria japonica, showing all AMF OTUs (a) and excluding AMF OTUs assigned to Glomus spp., and those categorized as “unclassified” and “uncultured” (b) in each sampling month.

Image adapted from: Djotan et al. / CC BY (Source)

Key Findings

  • In Japanese forests, a study found that soil pH changes with seasons affect tree-root fungi (AMF) composition
  • AMF communities in tree roots and soil remain stable year-round, but house different fungi species
  • A few dominant AMF types shift between tree roots and soil seasonally, suggesting an adaptive strategy
Arbuscular mycorrhizal fungi (AMF) are microscopic organisms that form a mutualistic relationship with plants, aiding them in nutrient absorption and providing resistance to environmental stressors. These fungi are found both within the roots of plants and in the surrounding soil, creating a complex network essential for the health of ecosystems. However, despite their importance, the dynamics of AMF in forest ecosystems, particularly how they change through the seasons and interact with soil properties, have not been fully understood. A recent study[1] by researchers from the University of Tokyo has shed light on this intricate relationship by examining the seasonal dynamics of AMF communities in conjunction with soil properties in forest ecosystems. The study focused on Cryptomeria japonica, a tree species native to Japan, collecting paired root and soil samples from two forest sites over the course of a year. The study found that soil pH and total phosphorus levels fluctuated with the seasons, while other factors such as total carbon, nitrogen, and the carbon-to-nitrogen ratio remained relatively constant. Interestingly, only soil pH was identified as a significant predictor of the composition and dynamics of the AMF community. This aligns with previous findings that the root and soil communities of AMF respond differently to soil pH[2]. The researchers observed that the total AMF community, comprising both root and soil fungi, exhibited significant seasonal variation, particularly from May to September. Contrary to this, the individual AMF communities within the roots and soil remained stable throughout the year, maintaining similar species richness despite housing significantly different AMF assemblages at any given time. A striking discovery was that the top two dominant AMF types (operational taxonomic units, or OTUs) displayed significant shifts between the roots and soils across the seasons, indicating an antagonistic relationship. This suggests that a few dominant AMF taxa may move between root and soil microhabitats in response to seasonal changes, a behavior that could be a strategy to maintain a functional symbiosis regardless of external conditions. The findings of this study build upon earlier research[3] that established the GlobalAMFungi database, a comprehensive collection of AM fungal distribution data. The database, which includes DNA sequences from various AM fungal taxon barcoding regions, has been instrumental in understanding the ecology of these fungi. The University of Tokyo's research contributes to this knowledge by providing specific seasonal dynamics data, which could be compared against the global patterns found in the database. Moreover, the study complements earlier work[4] that investigated the impact of habitat spatial distribution on AMF abundance. While the previous research focused on micro-landscapes and the spatial arrangement of plant hosts, the University of Tokyo's study adds a temporal dimension, showing how AMF communities adapt to seasonal changes within a given spatial context. In conclusion, the University of Tokyo's research offers valuable insights into the seasonal dynamics of AMF in forest ecosystems and their interaction with soil properties. It highlights the adaptability of AMF to maintain symbiotic relationships with their host plants throughout the year. This adaptability is crucial for the stability of forest ecosystems, which are subject to seasonal variations. Understanding these dynamics can inform conservation efforts and the management of forests, ensuring the sustainability of these vital ecosystems.

EcologyPlant ScienceMycology

References

Main Study

1) Year-round dynamics of arbuscular mycorrhizal fungi communities in the roots and surrounding soils of Cryptomeria japonica.

Published 20th March, 2024

https://doi.org/10.1007/s00572-024-01143-x

Related Studies

2) Paired Root-Soil Samples and Metabarcoding Reveal Taxon-Based Colonization Strategies in Arbuscular Mycorrhizal Fungi Communities in Japanese Cedar and Cypress Stands.

https://doi.org/10.1007/s00248-023-02223-9

3) GlobalAMFungi: a global database of arbuscular mycorrhizal fungal occurrences from high-throughput sequencing metabarcoding studies.

https://doi.org/10.1111/nph.19283

4) Arbuscular mycorrhizal root colonization depends on the spatial distribution of the host plants.

https://doi.org/10.1007/s00572-022-01087-0


Related Articles

An unhandled error has occurred. Reload 🗙