Rhizosphere ecology

Rhizosphäre - Hauptseite

Microorganisms of the rhizosphere promote plant growth and health. We explore the ecological significance of these microbial communities and their functional benefits for plants, humans and the ecosystem.

The high yields of modern agriculture rely mainly on the input of mineral fertilizers and chemical pest control. Because most agrochemicals are either derived from finite resources or their use has negative impacts on the environment, next-generation agriculture calls for alternative and sustainable strategies that allow to sustain crop productivity but with reduced inputs of agrochemicals. One solution is to capitalize on the rhizosphere microbial life and to take advantage of their services to host plant and the environment. Hence, a deeper understanding of the rhizosphere microbiota is required for the development of sustainable solutions for optimizing plant growth and controlling pathogen burden in the future.

The rhizosphere refers to the narrow zone of soil around the roots that is actively influenced by the plant. Plant roots continuously secrete a diverse array of chemical compounds that locally alter the soil environment (e.g. nutrient concentration and availability, oxygen levels, water content and pH). Seedlings exude up to 40%, and adult plants around 20%, of their photosynthetically fixed carbon into the rhizosphere and thereby generate a distinctive niche space for microbial life. Indeed, the microbial life surrounding the plant roots differs considerably in composition and activity compared to bulk soil.

Rhizosphäre - Wurzel

Most importantly, the activities of this rhizosphere microbiota directly affect plant growth and health and at larger scale the functioning of ecosystems. Rhizosphere-derived bacteria or fungi can promote plant growth or suppress soil-borne diseases while pathogenic rhizosphere members can cause disease and compromize plant growth. A few microorganisms belong to these „obvious" and well studied interactions whereas the majority of rhizosphere microbes appear symptomless. Remarkable little is known about the role of this inconspicious majority on plant growth and ecosystem functioning.

The goal of our research is to advance our understanding about the functional and ecological significance of complex rhizosphere microbial communities.