Diversity of arbuscular mycorrhizal fungi of Taiwan cypress along altitude in tropical forests
摘要
Elevation is known to influence arbuscular mycorrhizal (AM) fungal diversity and community composition, yet its effect on AM symbiosis in a single tree species remains poorly understood. Chamaecyparis formosensis is the AM tree and is an endangered and endemic cypress in Taiwan across mid-elevation regions. To elucidate the influence of elevation on their fungal partners, we characterized AM fungal communities associated with the roots and rhizosphere soils of C. formosensis across three regions along elevation gradients from 1500 to 2500 m. Seven AM fungal genera, Glomus, Acaulospora, Scutellospora, Archaeospora, Claroideoglomus, Diversispora and Gigaspora, were obtained and identified from roots or rhizosphere soils. Glomus was the dominant genus associated with the roots and rhizosphere soils. Notably, only a subset of the soil AM fungal species colonized the roots, suggesting host selectivity. Both alpha and beta diversity of AM fungal virtual taxa (VT) declined with increasing elevation, and fungal communities associated roots exhibited significant differences across elevation zones, whereas rhizosphere soil communities showed less variation. These shifts in AM fungal communities along elevation gradients might correlate with the complex interactions between the physiological state of host plants and environmental factors. Analysis of life history strategies revealed that most VT within Acaulospora, Archaeospora, Diversispora and Scutellospora function as competitors, while Glomus VT displayed ruderal, competitive and stress-tolerant strategies. Our findings underscore the importance of environmental factors on AM fungal preference in C. formosensis, contributing to our understanding of symbiotic interactions across ecological gradients and to the development of effective conservation strategies for this endangered tree.