Comparative metabolite and genome analysis of tuber-bearing potato species.

The cultivated potato Solanum tuberosum is unrivalled among crop plants for its wild relatives, which potentially represent an important source of genetic diversity to improve the nutritional value of potato varieties and understand metabolism regulation. The main aim of this research was to profile human health-related metabolites in a number of clones from 13 Solanum species. Results from HPLC-DAD and LC-ESI-MS analyses highlighted a high interspecific variability in the level of metabolites analysed. Ascorbic acid was confirmed to be the most abundant antioxidant in potato and chlorogenic acid the primary polyphenol. Generally, metabolite-based hierarchical clustering (HCL) and correlation networks did not group clones of identical species in the same cluster. This might be due to various factors, including the outcrossing nature of potato species, gene expression level and metabolic profiling techniques. Access to the genome sequence of S. tuberosum and S. commersonii allowed comparison of the genes involved in ascorbic acid, aromatic amino acid, phenylpropanoid and glycoalkaloid biosynthesis and helped interpret their respective pathways.