This project aims to diagnose and quantify Fusarium basal rot (Fusarium oxysporum f. sp. cepae) across onion growth stages using imaging techniques and biomarkers to understand host–pathogen interactions.
  • Dates1 Dec 2024 to 4 Dec 2028
  • SponsorBBSRC (FoodBioSystems DTP), Diamond Light Source (DLS), Moulton Bulb Co. LTD
  • Funded£157,692
  • PartnersUniversity of Reading, Diamond Light Source Ltd, Moulton Bulb Company Ltd

Onion (Allium cepa L.) is a globally vital crop, with annual production of 106 million tonnes, including 500,000 tonnes in the UK valued at £160 million. Production is increasingly threatened by Fusarium basal rot (FBR) caused by Fusarium oxysporum f. sp. cepae (Foc), which can result in yield losses of up to 50%. Detection remains challenging due to latent infections and reliance on destructive, late-stage diagnostics. Climate-driven soil warming further exacerbates disease pressure, intensifying risks to food security and economic sustainability.

This multidisciplinary BBSRC FoodBioSystems DTP project addresses critical knowledge gaps by evaluating advanced imaging and biochemical techniques to track Foc colonisation across onion developmental stages. Multi-scale, non-destructive approaches will elucidate infection progression, enabling earlier detection and supporting sustainable disease management and food waste reduction.

Progress update

Significant progress has been achieved across all project objectives. Sample preparation protocols have been optimised through chemical fixation and cryotome sectioning, enabling high-resolution FTIR spectroscopic analysis of intact onion tissues. Novel FTIR biochemical fingerprints have been established to distinguish onion cellular components and Fusarium oxysporum f. sp. cepae (Fo2), providing a robust diagnostic framework. High-resolution Xray-CT imaging has successfully visualised internal bulb structures for future non-destructive assessment of fungal colonisation. Furthermore, the first application of OCT to onion–Fusarium interactions has identified key technical constraints and informed the development of future 3D imaging systems. Collectively, these advances provide a strong foundation for biomarker discovery, disease modelling, and early pathogen detection.