Taxonomic and functional differentiation of soil and thallus microbiomes

Liverworts, as early-diverging land plants, host unique and ecologically important microbiomes, yet remain largely understudied in microbial ecology. In this study, we investigated the taxonomic and functional composition of microbial communities associated with Riccia sorocarpa, focusing on the thallus and adjacent rhizosphere soil. Using nanopore sequencing and metagenomic analysis, we reveal a significantly higher microbial diversity and functional specialization in the thallus microbiome compared to soil. Despite a shared core microbiota, specific bacterial and fungal taxa are selectively enriched in the thallus, likely driven by host-derived factors. Functional profiling highlights an overrepresentation of nitrogen and sulfur cycling, phototrophy, and plant-associated pathways in the thallus, whereas soil communities are dominated by heterotrophic decomposition processes. These findings support the concept of R. sorocarpa as a holobiont and emphasize the ecological and biotechnological potential of liverwort-associated microbiomes. Our results provide new insights into plant-microbe interactions in early land plants and their roles in ecosystem function and resilience.