Does genotypic variation in ethylene sensitivity affect crop response to soil compaction?

Hancke, Lis and Dodd, Ian and McAinsh, Martin (2025) Does genotypic variation in ethylene sensitivity affect crop response to soil compaction? Masters thesis, Lancaster University.

Text (2024LisandraHanckeMScByResearch)
2024LisandraHanckeMScByResearch.Final.pdf - Published Version
Available under License Creative Commons Attribution-NonCommercial-NoDerivs.
Download (9MB)

Abstract

Soil compaction limits crop growth and yields and is an increasing problem in modern agriculture as farming machinery has become heavier. Compacted soils have less pore space causing ethylene to accumulate and limit crop growth. This research aimed to identify whether (wheat, potato, and tomato) crop sensitivity to soil compaction in different cultivars depended on their sensitivity to ethylene. Ethylene sensitivity was assessed in wheat and tomato by placing pre-germinated seeds in Petri-dishes with 100 µmol of ethephon and allowed to grow until the roots were measured and the percentage reduction in root length calculated. In sprouted potato, minitubers (<20 mm) were placed into containers with 20 ppm of ethylene and root length measured to calculate percentage reduction in root length. Plants were grown in soils of varying levels of compaction, and a range of root and shoot morphological variables measured to identify whether varieties with higher sensitivity to ethylene responded more to compaction. Greater growth inhibition with compaction was positively related to ethylene sensitivity in most of the cultivars studied. Nevertheless, there were some unexpected results with an ethylene sensitive wheat cultivar showing increased growth under high compaction in an ethylene sensitive cultivar of wheat and also in an ethylene sensitive mutant of tomato. Overall, this research has demonstrated the importance of compaction effects on crop shoot and root growth and that these responses rely on ethylene sensitivity, and also that utilising less ethylene sensitive cultivars/genotypes may allow adaptation to increasing compaction.