Species of Aconitum subgn. Aconitum show very complicated patterns of morphological variation, resulting in confusion in delimiting species boundaries and in determining their relationships. Also, interspecific hybridization is relatively common in subgn. Aconitum, and many intermediated forms possibly derived from interspecific hybridization and introgressive hybridization have been reported. In the present study, we have examined the morphology and the flavonoid chemistry of putative hybrid populations of Aconitum subgn. Aconitum at Mt. Sobaek in southern Korea to understand the origin and structure of these populations. Five major morphological types were found among the individuals of these populations. Fourteen flavonoid compounds were isolated and identified from these populations at Mt. Sobaek representing these five morphological types. Characteristics of flavonoid profiles of the five morph types parallel the relationships suggested by the morphological evidence. In addition, the distribution pattern of flavonoid compounds among the individuals of the five morph types suggested that hybridization events involving at least three taxa probably occurred in these populations at Mt. Sobaek.

Key words: Aconitum subgn. Aconitum, Flavonoid chemistry, Hybridization, Introgression