Untargeted metabolomic profiling of sweet potato latent virus infected Nicotiana benthamiana

Viral diseases, the second most significant biotic stress, cause substantial yield loss and quality deterioration in sweet potato, and sweet potato latent virus (SPLV) is one of the dominant viral pathogens infecting sweet potato in China. To investigate SPLV-induced metabolic changes, untargeted LC-MS (liquid chromatography-mass spectrometry) was used on Nicotiana benthamiana inoculated with SPLV-infected sweet potato leaf sap. Principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA) confirmed distinct metabolite profiles between infected and mock control plants. In SPLV-infected plants, 626 metabolites exhibited significantly differential accumulation, with 429 upregulated and 197 downregulated. These differential metabolites were categorized into 14 distinct biochemical groups, and hierarchical clustering analysis intuitively visualized the expression patterns of the top 50 significantly different metabolites. Further, KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis revealed that 19 pathways were markedly perturbed upon SPLV inoculation. These results confirm SPLV’s significant effect on Nicotiana benthamiana metabolism, which helps elucidate SPLV-host interaction mechanisms and provides candidate metabolic targets for enhancing SPLV resistance in sweet potato.