Network of Rhizomorphs and  Ectomycorrhizas on oak roots. Photo: Sylvie Herrmann/UFZ

Research Field:

Biotic Interactions & Holobiome

Plants do not live alone but interact with myriads of animals, other plants and soil microorganisms. Soil is the resource of microbial diversity from which the plant selects its microorganisms. It is the plant and these interacting communities that are referred to as a „holobiome“, a unit that reacts to environmental variations and goes through evolution.

To study the holobiome, we are using own experimental platforms. One consists of a clonal oak (DF159) that is micropropagated to regenerate genetically identical trees for experiments in microcosms or in the field. In the TrophinOak project, we have developed tools to characterize the genome of this tree and its regulation when engaged in multitrophic interactions, under consideration of resource allocation in the tree during its specific endogenic rhythmic growth. In the PhytOakmeter project we released saplings of the DF159 clone across several locations in Europe and Central Germany. Here the goal is to characterize how the saplings and their holobiome adapt to different climatic conditions and to anticipate how they will react to global change.

Furthermore, the feedback processes between maize and soil microbiota during the organization of the rhizosphere, which represents the soil volume affected by living maize roots, are addressed in the project Rootgenes.


Carbon allocation shifts from roots during root flushing to shoots during shoot flushing. Graphic: Hermann et al. 2015, doi: 10.1093/jxb/erv408
Semi-sterile petri dish system with gamma-sterilized soil and the clonal oak DF159. Photo: Sylvie Herrmann/UFZ
Development of a new shoot flush of the oak DF159. Photo: Sylvie Herrmann/UFZ
Mycorrhizas development on oak roots and mycelial network. Photo: Sylvie Herrmann/UFZ
Assessment of gene expression levels of oak in mycorrhizal symbiosis with the fungus Piloderma croceum; red dots indicate differential gene expression. Graphic: Tarkka et al. 2013, doi: 10.1111/nph.12317
Caterpillar attack on oak DF159 in Kreinitz (Middle-Germany). Photo: Sylvie Herrmann/UFZ
Aphids attack on oak DF159 in Kreinitz (Middle-Germany). Photo: Sylvie Herrmann/UFZ
Spider webs on oak DF159 in the INRA Station of Bordeaux (France). Photo: Sylvie Herrmann/UFZ
In vitro propagation of oak DF159 on agar medium at the UFZ. Photo: André Künzelmann/UFZ
Mildew attack on oak DF159 at the field station of Bad Lauchstädt (Middle-Germany). Photo: Sylvie Herrmann/UFZ
Anticyclic shoot length growth and soil activity determined by the alternating root and shoot growth of the oaks. Graphic: Eisenhauer et al. 2018, doi: 10.1016/j.tree.2018.09.010
Acorn formation of Oak DF159 in Kreinitz (Middle-Germany). Photo: Sylvie Herrmann/UFZ

Maize Soil Column Experiment: maize plants at 2 weeks age on loamy soil; Priority program Rhizosphere. Photo: Mika Tarkka/UFZ