关键词: 孑遗植物, 植物部位, 偏好性真菌, 扩散限制, 功能类群

Abstract

Aim: This study explored the community diversity and ecological process mechanisms of the fungal communities associated with different compartments in Tetraena mongolica Maxim. 

Methods: Leaf, root and soil samples were collected from the T. mongolica, and Illumina high-throughput sequencing targeting the fungal ITS1 region was employed to analyze the fungal diversity and composition. Additionally, preference analysis and LEfSe analysis were adopted to detect the biomarker fungi for each plant compartment, and the NCM, MST and iCAMP approaches were used to examine the ecological processes involved in the assembly of the fungal communities. 

Results: A total of 752 fungal operational taxonomic units (OTUs) were identified across five plant compartments. Significant differences in fungal diversity and composition were observed among compartments, with niche-preferential OTUs and biomarker taxa specific to each compartment. Fungal diversity decreased progressively from the rhizosphere soil to root and then leaf. Epiphytic samples of roots and leaves harbored higher fungal diversity than endophytic samples. Integrated analyses using the Neutral Community Model, Modified Stochasticity Ratio, and Infer community assembly mechanisms by phylogenetic-bin-based null model analysis revealed that stochastic processes, particularly the dispersal limitation and ecological drift dominated fungal community assembly, and ecological processes played different importance in determining fungal community assembly of different plant compartments. 

Conclusion: This research revealed for the first time the community diversity and community assembly mechanisms of the fungi of the endangered relict plant T. mongolica, and this study provides a scientific basis and practical guidance for conserving rare relict plants.

Key words: Relict plant, Plant compartment, Preference fungi, Dispersal limitation, Functional group