Comparative analysis of two stored sweet potato varieties using integrated transcriptomics and metabolomics

Texture, color, antioxidant capacity, and disease resistance of sweet potato varieties differ, but information on metabolic differences among varieties is limited. This research investigated the alterations in volatile substances, gene expression quantities, and metabolites during the storage process of two varieties of sweet potatoes: 'Xiguahong' and 'Yanshu25'. The GC-IMS findings indicated that compounds possessing appealing aromas, including 2-ethylpyrazine, γ-terpinene, and ethyl isobutyrate, were more concentrated in 'Xiguahong'. The expression levels of phenylpropanoid biosynthesis genes (<italic>PAL</italic>, <italic>CCR</italic>), flavor-related genes (<italic>MLS</italic>, <italic>LOX6</italic>), color-related genes (<italic>PSY2</italic>, <italic>CRTISO</italic>), and resistance-related genes (<italic>PPO1</italic>, <italic>GSTL</italic>) were higher in 'Xiguahong'. Phenolic acids, flavonoids, terpenes, lignans, and coumarins content increased more in 'Xiguahong' than in 'Yanshu25'. This study provides insights into the molecular mechanisms underlying post-harvest quality changes in different sweet potato varieties.