How Useful Are Plant Traits in Explaining Variation in Phyllosphere Microbial Abundance and Composition Across Hosts?

Area of Science:

• Plant-microbe interactions
• Microbiome assembly
• Phyllosphere ecology

Background:

• Plant taxonomy is a known driver of plant-microbe associations, but underlying mechanisms are unclear.
• Plant traits may offer more direct explanations for microbial community structure than taxonomy alone.
• The general predictive power of plant traits for plant-microbe associations remains largely unknown.

Purpose of the Study:

• To systematically review phyllosphere literature and assess if specific plant traits consistently explain leaf microbial variation.
• To evaluate the predictive capacity of plant traits for microbial abundance and composition within and among plant species.

Main Methods:

• Conducted a systematic review of over 100 studies focusing on the phyllosphere microbiome.
• Analyzed literature to identify plant traits consistently associated with leaf microbial community composition and abundance.

Main Results:

• Plant traits associated with development, primary metabolism, and defense significantly shaped leaf bacterial and fungal communities.
• These traits proved relevant for predicting plant-microbe associations in the phyllosphere.
• However, most tested plant traits did not influence microbial composition more than expected by chance.

Conclusions:

• Rethinking the scale and selection of plant traits is crucial for microbiome assembly studies.
• Refining taxonomic resolution in microbial community analysis is important.
• Considering stochastic processes and historical factors may improve understanding of plant-microbe associations.