Plant-bacteria associations are phylogenetically structured in the phyllosphere

Area of Science:

• Ecology and Evolution
• Microbial Ecology
• Phylogenetics

Background:

• Global change may create novel host-microbe interactions, impacting ecological and evolutionary dynamics.
• Understanding host and microbial evolutionary histories is crucial for predicting fitness consequences of these new associations.

Purpose of the Study:

• Investigate how host and bacterial phylogenetic relatedness influences bacterial distribution on tree leaf surfaces (phyllosphere).
• Evaluate the role of functional traits in explaining these host-microbe associations across diverse tree species.

Main Methods:

• Utilized shotgun metagenomic and amplicon sequencing to analyze bacterial communities.
• Examined phylogenetic relatedness among host trees and their associated bacteria.
• Assessed functional gene variations in bacteria across different host types (gymnosperm and angiosperm).

Main Results:

• Phylogenetically similar hosts harbored similar bacterial communities, and vice versa.
• Host-bacterial phylogenetic interactions explained significant variation in their associations.
• Early ecological variations in plant and bacterial phylogenies were key drivers of current associations.
• Bacterial genes related to amino acid biosynthesis and motility were important for community turnover between gymnosperm and angiosperm hosts.

Conclusions:

• Host and microbial evolutionary histories significantly influence contemporary associations.
• Phylogenetic relatedness and functional traits play critical roles in structuring phyllosphere microbial communities.
• Early evolutionary events have lasting impacts on host-microbe interactions in the face of global change.