Microbial interactions and co-evolution in the plant phyllosphere

Plants are associated with a variety of microorganisms. Some microbial species are highly specialized to a plant-associated lifestyle and play a detrimental role in plant health either by promoting growth or conferring disease.

In spite of their fundamental importance, we know surprisingly little about the evolution and biology of these microbial species. We use the fungal grass pathogen Zymoseptoria spp as a model system to study microbial speciation and host specialization by integrating experimental and computational approaches. The species Z. tritici has co-evolved with wheat during domestication. Host specialization of this pathogen has involved the acquisition of adaptive substitutions in pathogenicity-related genes and changes in gene expression.

Using a metabolomics approach we demonstrate that Z. tritici, in susceptible hosts, is able to suppress and manipulate multiple biosynthetic pathways of wheat and notably pathways involved in immune responses during infection.

Interestingly, suppression of the plant immune responses conferred by Z. tritici is so efficient that it impacts the ability of other microbial species to colonize the plant tissue, even in distal areas of the leaf not colonized by the fungus. Consistent with this observation we find that Z. tritici produces a large diversity of anti-microbial compounds, which may be important for the pathogen to co-exist with the wheat-associated microbiota. Our findings suggest that host specialization of pathogens not only entail specialization to a given host, but also to the host microbiota. 

Don´t miss this seminar by Eva Holtgrewe Stukenbrock, Environmental Genomics, Botanical Institute, CAU Kiel and MPI for Evolutionary Biology, Plön, Germany

All are most welcome to attend via Zoom:  

https://slu-se.zoom.us/j/68473399009  

Meeting ID: 684 7339 9009

Passcode: 241797