Geographic patterns and soil-to-bark microbial transmission shape microbiome assembly in tea trees

Area of Science:

• Microbial Ecology
• Plant-Microbe Interactions
• Agricultural Science

Background:

• Understanding the tea plant (Camellia sinensis) microbiome is crucial for identifying beneficial microbial interactions.
• Economically important woody plants rely on complex microbial communities for health and productivity.

Purpose of the Study:

• Investigate microbial community characteristics, source-sink dynamics, and driving factors in tea tree bark and soil.
• Analyze functional differentiation and ecological roles of microbes in distinct niches.
• Identify key microbial biomarkers in tea plant ecosystems.

Main Methods:

• Amplicon sequencing for microbial community profiling.
• FEAST source tracking to determine microbial origins.
• Functional prediction analysis to infer metabolic capabilities.
• LEfSe analysis for biomarker identification.

Main Results:

• Bulk soil serves as a primary microbial reservoir for tea bark, with significant bacterial and fungal sharing.
• Soil exhibited higher alpha diversity, while bark selectively enriched specific taxa.
• Plant type and geographic location significantly influenced microbial community composition.
• Total nitrogen and organic matter in soil were key drivers of microbial variation in both soil and bark.
• Distinct functional profiles were observed: soil microbes involved in nutrient cycling, bark microbes in carbon fixation and stress resistance.
• Identified key bacterial (e.g., Xanthobacteraceae) and fungal (e.g., Pleosporaceae) biomarkers.

Conclusions:

• Soil plays a critical role as a microbial reservoir for tea plants.
• Niche-specific factors significantly shape microbial communities along the soil-bark continuum.
• Provides a framework for understanding microbial diversity regulation in tea plant ecosystems.