Eco-evolutionary dynamics of soil microbiomes for crop health

Background

Soil microbes can interact with plants to enhance plant defence against pests and disease. A set of bacteria are already being studied for their potential in sustainable agriculture, yet bacterial diversity in soils is extremely high with many potentially beneficial microbes as yet uncharacterised. Plants naturally exploit the soil microbiome by establishing symbioses with specialised fungi for long-term benefits and recruiting beneficial bacteria to quickly respond to changing abiotic and biotic conditions.

The resulting rhizosphere soil is therefore adapted to the prevalent conditions and will contain communities of microbes that are beneficial either individually or as a whole community for the plant.

We will use a plant-microbe-insect experimental system to study the effects of adaptation, evolution and ecological dynamics on the soil microbiome of plants under attack from aboveground sap-feeding insects. The soil microbiome (bacteria and fungi) will be analysed using metabarcoding approaches, and soil transcriptomics can be used to identify the ecologically relevant gene functions under selection.

Objectives 1. To experimentally evolve soil microbiomes in response to insects feeding on the plants

2. To understand the impact of inoculation of known beneficial bacteria on the adaptive potential of field soils to insect attack 3. To explore the potential for creating pest suppressive soils through a set of reciprocal transplant experiments Novelty and Timeliness

Harnessing soil microbiomes for sustainable agriculture is a quickly developing area, as the importance of a well-functioning soil ecosystem for crop health is being fully appreciated. Using eco-evolutionary approaches to identify novel bacteria and fungi can maximise future impacts across multiple environments. The development of standard high-throughput techniques for identifying microbes from soils, and their functions, now enables the full potential of soil diversity to be studied under an ecological and evolutionary framework