The smut fungus Thecaphora thlaspeos – a potential hub in Brassicaceae microbiomes.
Plants are a niche for microbes such as bacteria, fungi and oomycetes that together with the plant form the holobiont. Microbes of the holobiont, the so-called microbiome are highly diverse creating a complex evolutionary landscape of plant-microbe and microbe-microbe interactions. In my CEPLAS project I aim to understand how the plant pathogenic fungus Thecaphora thlaspeos interacts with the microbiome of Arabidopsis thaliana and how this interaction impacts plant fitness.
T. thlaspeos is a basidiomycete that adapted to Brassicaceae host plants. It establishes a systemic infection that lasts over months without causing macroscopic symptoms. The infection cycle finishes with the production of sexual teliospores that develop inside seed pods by replacing the seeds with spores. This particular life cycle requires balanced virulence and a high degree of adaptation to the host, and might also depend on specific interactions with the plant microbiome.
I hypothesise that host adaptation also required adaptation to the plant microbiome and that T. thlaspeos is a microbial hub which actively shapes the community structure of Brassicaceae-association microbes. To challenge my hypothesis I study the model plant A. thaliana. Using amplicon sequencing I monitor how the structure of microbial communities, isolated from wild A. thaliana populations, change in the presence/absence of T. thlaspeos over time. In addition, I co-infect A. thaliana with T. thlaspeos and the plant-biotrophic oomycete Albugo laibachii to characterise microbiome formation in the presence of the two competing plant pathogens.
My project will contribute to our understanding of how plant pathogens interfere with holobiont plant-microbe and microbe-microbe interactions, and how this interference creates niche differences between infected and non-infected plants.
Keywords expertise: plant-microbe interactions, evolution, genomics, molecular genetics, phylogenetics, fungi, oomycetes