“…Factors such as vacuolar pH, copigmentation, formation of meta1 comp1exes and the shape of epidermal ceIls, contribute to the final expression of flower colour. Considerable progress has been made in e1ucidating the biosynthesis and genetics of pigments (Forkmann, 1993;Forkmann et al, 1995;Davies and Schwinn, 1997). Especially for the flavonoids, several genes encoding important biosynthetic enzymes have been isolated and used for genetic transformation of some ornamental species.…”