ec17981@bristol.ac.uk; claire.grierson@bristol.ac.uk; k.j.edwards@bristol.ac.uk; malcolm.hawkesford@rothamsted.ac.uk; xiaoxian.zhang@rothamsted.ac.uk; hannah.cooper@nottingham.ac.uk; richard.whalley@rothamsted.ac.uk; sacha.mooney@nottingham.ac.uk

The Global population is increasing rapidly, and the yield of staple crops like wheat must be increased to feed everyone. Despite this, recent peer reviewed research indicates that an annual total of nine million tonnes of wheat are lost globally to soil erosion – equivalent to total UK wheat production in 2020. Declining crop yields are traditionally increased by agricultural intensification; however, this causes soil degradation and desertification, which exacerbates the issues facing food production.

Therefore, reducing the loss of arable land is critical for the future success of agriculture. One potential solution is root exudates, which aggregate soil particles and therefore improve soil structure.

There is much to understand about root exudates and the pathways for their release, but the two candidate genes xyloglucan endotransglucosylase 23 (XTH23) and ABC2 homolog 6 (ATH6) have been proposed to affect exudate compositions. We are using Arabidopsis mutants in these genes for uprooting and soil binding experiments to compare their adhesive properties.

To investigate whether these genes have similar functions in monocots and dicots, the results from these experiments will be compared to similar results from wheat mutant experiments. This has required the creation of wheat ATH6 mutants using TILLING lines. CRISPR technology has also been utilised to create XTH23 wheat mutants.

The CRISPR process was completed in house, using golden gate cloning to make the constructs that were introduced to the wheat genome though biolistic transformation. Subsequent genotyping has successfully identified CRISPR mutants lacking the majority of their coding sequences which can be taken forward for exudate analysis.

This has required the development of a new assay for quick and facile wheat root exudate collection as well as a new uprooting assay to help measure root-soil cohesion in wheat.