The role of plant root exudates in controlling rhizobacterial transcriptomic responses to plant nutrient stress

In order to survive and grow, plants use light to turn atmospheric carbon dioxide into sugars, in a process called photosynthesis. However, they require more than just sugars for growth, and the additional nutrients they need (e.g. phosphorus, nitrogen, sulfur) are obtained from the soil, being taken up by the roots. To obtain these nutrients efficiently, plants need to cooperate with the prolific community of bacteria and fungi that live in, on and around their roots. These organisms profit from excess sugars produced by plant photosynthesis - the plant releases these from its roots as plant root exudates and they form the major food source for soil microbes. In return, the bacteria and fungi play a crucial role in providing the plants with nutrients that are otherwise not available. This project is looking at how the microbes around the root respond when the plant is starved for essential nutrients. We know that the plant secretes different root exudates under these conditions, and we predict that these changes are an important part of how a plant communicates with its microbial neighbours. Most interestingly, the plant may be signalling to the microbes that it is starving, and stimulating them to deliver more of the nutrients that it needs / by examining the microbe response we can see whether the plant's message is getting across, and we can learn how to adapt these signals to solve agricultural and land management problems.