Genetic regulation of flavonoid content in seeds and seedlings of Melilotus alba

Chemical analysis of seeds and seedlings of the CC and cc genotypes in Melilotus alba indicated that these alleles affect flavonoid biosynthesis. The CC seed coats contained orientin and iso-orientin, which were absent in the cc seed coats. The pigment responsible for the red pigmentation of young seedlings of CC genotypes was a cyanidin glycoside. The embryos of seeds of both the CC and cc genotypes contained a flavonoid tentatively identified as a 6,8-di-C-pentosylapigenin. The observation that 3′,4′-dihydroxyflavonoids were absent in the cc genotype and that 4′-hydroxyflavonoids were present in both genotypes indicated that the C/c alleles controlled the 3′-hydroxylation of flavonoids. The C/c alleles did not, however, control 3′-hydroxylation of cinnamic acids since caffeic acid was detected in both genotypes.