INHERITANCE OF FLOWER COLOR AND FLAVONOID PIGMENTS IN GERBERA

The flower colour of Gerbera, an important ornamental cut flower, is d erived from carotenoids and flavonoids. The knowledge of enzymological and genetic control of flavonoid biosynthesis is still incomplete. Th e present paper summarizes the results obtained at our institute betwe en 1981 and 1993. The material for the investigation of phenotypic seg regation and segregation of flavonoids after chromatographic analysis came from 408 progenies of controlled crosses. Phenotypic segregation analysis showed acyanic genotypes to be homozygous recessive and reces sive epistatic over cyanic genotypes, respectively. This was confirmed by the existence of two loci controlling steps in biosynthesis (fht, dfr or ans) showing recessive mutants and complementary gene action af ter crosses. Flavone formation is effected by one dominant allele (fns (+)); dominant and recessive genotypes are now available. Regarding an thocyanidin inheritance, an unusual epistasis of 4'-hydroxylation (pel argonidin formation) over 3',4'-hydroxylation (cyanidin formation) was observed. Final proof of the postulated gene actions will come from e nzymological and molecular biological investigations of the chemogenet ically defined Gerbera genotypes now available.