Morphology and metabolite profiles of southern and northern Chrysanthemum in China

Abstract

Chrysanthemum is a valuable domesticated crop with numerous cultivars. The medicinal cultivars in China can be divided into southern and northern Chrysanthemum. They differ significantly in phenotype, taste and usage, but the variation in their metabolite profiles is unknown. In this study, targeted and untargeted metabolomics were combined to characterize and quantify an array of secondary metabolites across 15 Chrysanthemum cultivars. Differential metabolites identified between southern and northern Chrysanthemum revealed that flavonoid glycosides were more abundant in southern Chrysanthemum, while flavonoid aglycones, phenolic acids and terpenes were more abundant in northern Chrysanthemum. Methoxylated flavonoids were the characteristic flavonoids of northern Chrysanthemum, while hydroxyflavone were rich in southern Chrysanthemum. These findings indicated that the biosynthetic pathways of Chrysanthemum under different geographical environments were diverse. Furthermore, tubular flowers and bracteoles were positively correlated with flavonoid glycosides and terpenoids, respectively. This study established an identification model to distinguish southern and northern Chrysanthemum, enhanced the understanding of the metabolite–phenotype relationship, as well as provided a basis for the rational exploitation and breeding of Chrysanthemum.