Translating the chemical cross-talk between plants and root symbionts through application of novel microfluidics devices

Plants associate with multiple symbionts. Some, such as arbuscular mycorrhizal fungi (AMF), can offer important nutritional benefits to their host whereas others, e.g. parasitic nematodes, are detrimental to the host plant. Parasitic interactions can affect the outcomes of mutualistic partnerships and vice versa through competition for plant resources. This is problematic in sustainable food production systems where sought-after beneficial interactions between crops and AMF are often encouraged. This can inadvertently drive increased nematode density thereby reducing AMF efficacy. Initiation and establishment are critical steps for plant symbioses and are driven by chemical signals produced by the potential host and its symbionts. Due to the technical challenges imposed by the soil environment, defining the key differences and similarities in the chemical ‘language’ used in initiation, establishment and functioning of competing plant symbioses remains a challenge, particularly where they occur simultaneously.

This project, which is a collaboration between mechanical engineers and biologists, will take a multi-disciplinary approach to design and develop a novel microfluidics platform to investigate and manipulate interactions between plant roots and multiple competing symbionts. It will use the transparent microfluidic devices, which can harbour the growth of plants for a number of weeks, to characterise the chemical cross-talk between plant roots, nematodes and AMF. The precise and repeated non-destructive sampling facilitated by the new devices will allow exudation chemistry to be matched with root and AMF/nematode development. Elucidating the composition and precise spatial and temporal dynamics of signaling chemistry in the rhizosphere could allow the functional outcomes of multi-symbiont interactions can be manipulated. Application of key compounds involved in initiation of symbiosis may enhance root colonisation by AMF and/or infection by nematodes. This will be investigated first in microfluidic devices then a series of pot-based experiments will be carried out to validate whether inoculation with rhizosphere signalling chemicals can impact colonisation in soil-based systems.