Theme: Biodiversity and conservation science, Ecology genetics and evolution, Environmental management

Description: Plants release up to 50% of photosynthetically derived carbon from their roots as a complex mixture of organic compounds known as root exudates. These compounds fuel diverse root-associated microbial communities that consist of plant growth-promoting species as well as those that cause disease or compete with plants for resources. By changing the mixture of exudates released from their roots, plants are thought to exert some level of control over the selection of their microbial symbionts.

Current evidence indicates that most root-associated microorganisms are chemotactic, i.e. they have the ability to sense substrates released by roots and direct movement towards them. This ability enables them to respond rapidly to resources as they become available and out-compete neighboring populations. At present there is no information regarding the selectivity of different exudate components for specific groups of chemotactic organisms. Here, we will use a novel chemotaxis assay in combination with high-throughput sequencing and flow cytometry to identify and enumerate microorganisms that respond to different root exudate components. This information will identify exudates that are strongly associated with the recruitment of beneficial and/or deleterious organisms and should facilitate the development of crops that select for beneficial root-microbial communities.


Contact: Associate Professor Paul Dennis