Abstract
This paper deals with the genetic analysis of flower color in Portulaca sp. 'Jewel' using X-ray mutants. And it is also discussed on the gene for betalain biosynthesis as a marker for the change in the character. Two genes, M1 and M2 appeared to be located on the same chromosome for the expression of fiower color, with M1 being epistatic to M2. Another gene L was recognized for its hyperchromic effect on pigmentation. By means of High-performance Liquid Chromatography, biogenesis of betalain pigments was compared among the strains. Constitution of pigments in the mutants was different from that of the pigments of original strain. M2 gene was responsible for the susceptibility to changes in the temperature during the following stages. Activity of crude extracts of the enzyme was investigated among the strains. It was demonstrated that XM-3 which harbored m2 gene promotes the glycosidic degradation of betanin.
