Ökologie des Kern-Mikrobioms von natürlichen Lotus corniculatus-Populationen

01/02/2019 to 31/01/2023

Understanding the diversity and dynamics of plant-inhabiting
microbiota is one of the key challenges in current plant science. From
which microbial sources are plants colonized? What are the
mechanisms that structure and maintain microbial communities?
What explains microbiome variation among plant organs, genotypes
and species, as well as between different environments? Recent
studies on microbial communities of the model species Arabidopsis
thaliana have identified a small subset of ‘hub’ microbes that are
strongly interconnected and have large impact on microbiota structure
and diversity. They have also shown that such hub species can link
host genotype and environmental factors to microbiome diversity.
However, our understanding of the origin and stability of the core
microbiome, and in particular to what degree it is variable in natural
plant populations, is still very limited. To address these gaps in our
knowledge, we need to study more different plant species that are
widespread and occur across a broad range of natural environments,
and we need to study them also in situ. We propose to study the
common legume Lotus corniculatus, an important species in Central
European grasslands. We will take advantage of the research
platform Biodiversity Exploratories where L. corniculatus occurs on a
range of different soils and under different land use regimes. The
unique metadata available for these populations will allow us to
incorporate various ecological factors into our microbial network
analyses of L. corniculatus rhizospheres, shoots, flowers and seeds,
and thus to disentangle different drivers of natural microbiome
variation. A particular focus will be on the two fundamental modes of
microbe transmission: vertical transmissiom through seeds, and
horizontal transmission through pollinators or other vectors and
shared environmental conditions. We will also link our microbiota
analyses to host fitness and host genotype effects. Our study will
combine extensive field surveys with advanced microbial network
analyses, and a series of controlled-environment experiments. It will
thus provide a uniquely comprehensive study of plant-inhabiting
microbiota in ecological context.