Fusarium disease presents a formidable challenge to shallot (Allium cepa L.) production globally, necessitating a profound understanding of the plant’s defense mechanisms. Secondary metabolites play a pivotal part in plant-pathogen dynamics, yet their roles against Fusarium oxysporum f. sp. cepae (FOC) in shallots remain underexplored. In the presented study, the use of Gas Chromatography-Mass Spectrometry (GC-MS) helped profile the secondary metabolites in six shallot genotypes, i.e., Bima Brebes, Sumenep, Tajuk, Katumi, Biru Lancor, and Maja Cipanas. The analysis revealed substantial variations in the quantity and diversity of compounds between the Fusarium disease infected and non-infected shallot treatments. However, the infected shallots exhibited a more pronounced metabolite profile (168 vs. 95). Notably, the susceptible shallot cultivar Katumi enunciated the highest metabolite production across both conditions. Clustering analysis identified four distinct metabolite clusters for infected and non-infected shallots. Heatmap analysis highlighted elevated levels of cholesterol derivatives, sterol, and linoleic acid in the shallot resistant cultivar Sumenep, positioning these compounds as promising biomarkers and crucial elements in the defense strategy of shallots against Fusarium disease.
Shallot (A. cepa L.), biomarkers, clustering analysis, Fusarium disease, GC-MS, resistance mechanism, secondary metabolites
The study unveiled significant variations in secondary metabolites between the Fusarium disease infected and non-infected shallot (Allium cepa L.). However, the infected treatments showed greater diversity and expression (168 compared with 95). Notably, in the shallot resistant cultivar Sumenep, the cholesterol derivatives, sterol, and linoleic acid were considerably higher, indicating their potential as biomarkers for resistance against Fusarium disease.