Following ethylene: from the synthesis site to target root tissues and into compacted soil.

Soil compaction is a severe abiotic stress challenging crop production in Europe, and particularly UK. Moreover, the agronomic

machinery needed to maintain or enhance crop production efficiency is has been increasing in weight over the last decades. At the

same time, climate change is increasing the frequency and intensity of other abiotic stresses such as droughts. Soil compaction can

occur together with such stresses leading to exacerbated detrimental effects on root architecture, shoot biomass, and yields.

Recently, the plant hormone ethylene was identified as a key hormone regulating root growth responses during compaction, and

mutants insensitive to ethylene can grow in compacted soils. This opens the possibility of creating cell specific crops insensitive to

ethylene tolerant to soil compaction. However, several fundamental questions remain about ethylene diffusion before such crops can

be developed. Where is ethylene exactly synthesized? How does it move from source tissues to target cells, and finally into the soil?

And importantly, which tissues are targeted by ethylene to inhibit root growth? These fundamental questions will be answered in this MSCA project in the context of soil compaction.

The results of this highly interdisciplinary project will unravel fundamental knowledge about ethylene diffusion and the key tissues

affected by this hormone during soil compaction. Moreover, the project will generate the first mathematical model for ethylene

diffusion from the cells to the rhizosphere. This will pave the way to develop soil compaction resistant varieties and creating the

resources to study ethylene diffusion during other stresses, thus impacting multiple fields of research. Finally, this project will allow

me to master advanced molecular and imaging methods and develop a new state-of-the-art method to measure ethylene directly in the soil.