Dr. Stephan Greiner

Group “Cytoplasmic and Evolutionary Genetics”

The research group led by Dr. Stephan Greiner dealt with molecular and mechanistic aspects of plant evolution and breeding. The focus was on the role of cytoplasmic elements (organelle genomes of chloroplasts and mitochondria) in plants in speciation, adaptation and development processes. The group investigated the genetic and physiological consequences of local adaptations of organelle genomes to diverse habitats. Among other things, genome segments in the chloroplast were studied that are partly responsible for adaptation to arid regions, and these findings were transferred to crop plants such as barley. The model plant used was evening primrose (genus Oenothera), in which two different chloroplasts can be combined in one plant via normal crosses. This allows a quick and easy exchange of organelle genomes between species, e.g. to test the adaptive potential of a particular chloroplast genome under given environmental conditions. Such experiments have brought to light a remarkable influence of organelle genomes on plant development via so-called retrograde signals. Moreover, sexual and functionally asexual forms occur in evening primrose in overlapping habitats as crossable species. With the aim of developing new breeding approaches, these asexual evening primroses were used to understand their inheritance mechanism. This involved stabilization of heterosis as well as suppression of homologous recombination in meiosis.

Link to an article about the research of Dr. Stephan Greiner in Max Planck Research: Untrue to Type