Jocelyn Lauzon

Université du Québec à Montréal
M.Sc. candidate

Supervisor: Steven Kembel
Jean-Baptiste Leducq, Université Laval
Start: 2023-01-26
End: 2024-12-20

Project

Methylobacterium phyllosphere populations: genetic bases of adaptations to tree host species in the northern temperate forest
The phyllosphere – the aerial part of plants, notably the leaves – harbors diverse bacterial communities playing key ecological roles in forest ecosystems. Methylobacterium is an ubiquitous bacterial genus of the phyllosphere. Methylobacterium are known for stimulating plant growth and protecting their hosts against pathogens. The phylogeny and ecology of the genus is well documented. However, the genetic mechanisms underlying the adaptations of Methylobacterium populations to different phyllosphere niches – such as the genes responsible for adaptations to differents plant host species – are still relatively unknown. To bridge the gap between genes and ecology, my project studies the genomic content of Methylobacterium’s natural populations residing on the foliar surface of five trees and shrubs species characteristic of the northern part of the decidual temperate forest (Abies balsamea, Acer saccharum, Corylus cornuta, Fagus grandifolia and Thuja occidentalis) by mapping metagenomic sequences to the genomes of the different species composing the genus’ pangenome – an approach known as metapangenomics. My objectives are (1) to reveal genes and functions of the accessory pangenome that are associated with different host species, and (2) to analyze the phylogenetic signal structuring these genes-hosts associations on the leaf surface of these trees and shrubs host species forming an important part of the northern temperate forest canopy.

Keywords

Microbiome, Phyllosphère, Methylobacterium, Ecologie forestière, Biodiversité, écologie microbienne, bactéries, Génomique