Our overarching research goals are (i) to uncover and identify patterns of plant and fungal diversity at various levels and (ii) to reach a solid understanding of the ecological, evolutionary and molecular mechanisms underlying the origin and maintenance of this diversity. To this end we use a broad conceptual basis and apply methodologies rooted in evolutionary genomics and systematics, biogeography, evolutionary cytogenetics, ecological genomics including epigenetics, and chemodiversity of plants and fungi. Combining these approaches within one integrated research unit enables us to tackle some of the currently most pressing questions concerning the origin, loss, and maintenance of biological diversity in plants and fungi at all relevant spatial, temporal, taxonomic, and hierarchical / organismal scales. Furthermore, the knowledge and expertise gained from our research provide the basis for science-based conservation efforts and are an essential part of research-oriented teaching at all academic levels.