FOLIAR FLAVONOIDS OF EASTERN NORTH-AMERICAN VITIS (VITACEAE) NORTH OFMEXICO

Twenty-one flavonoid glycosides were isolated from the leaves of 22 No rth American Vitis L. taxa, representing two subgenera and five series . Three chemical groups were evident: one producing flavonols, flavone s, and C-glycosylflavones, a second producing flavonols and flavones, and a third producing only flavonols. These three chemical groups did not correspond to any of the subgeneric groupings based on morphology. However, flavonoid distributions within series in each subgenus corre late well with morphological data. Parallel flavonoid evolution within each series is thought to account for this lack of subgeneric and int erserial flavonoid distinction. The flavonoid data indicate that serie s Cordifoliae of subgenus Vitis, particularly V. vulpina L., is the mo st closely related group to subgenus Muscadinia (PLANCH.) REHDER, and represents an evolutionary link between the two subgenera.