Novel Flavonoids and Reticulate Evolution in the Phlox Pilosa–p. Drummondii Complex

The nonanthocyanin flavonoids of the diploids Phlox pilosa ssp. pilosa and P. drummondii ssp. mcallisteri and their putative allotetraploid derivatives P. aspera and P. villosissima were characterized by chromatographic and spectrophotometric analyses. Synthetic F1 diploid hybrids were also examined. All but one of the compounds encountered were glycoflavone (C‐glycosyl) derivatives of either apigenin or luteolin. Although some compounds were present in all four taxa, most were species‐specific. Together, the diploids exhibited 15 different flavonoids. Half of each tetraploid ensemble was composed of novel flavonoids, compounds not manifest in either diploid ancestor. In total, the tetraploids produced seven different novel flavonoids. Five novel compounds differed from particular diploid compounds only in number or kind of oxygen‐linked sugar substituents. Ostensibly, these five are either identical to diploid biosynthetic intermediates or share common precursors with related diploid end products. The mode of origin of all novel compounds is discussed.