Anthocyanin biosynthetic genes in Hemerocallis and Dianella

Daylilies (Hemerocallis) like roses and carnations do not have naturally blue flowers. Plants like Dianella , petunia and snapdragons do have naturally blue flowers. The blue pigment, delphinidin, arises from the biochemical reactions catalyzed by enzymes in the branching anthocyanin biosynthetic pathway, which starts with p-coumaroyl-CoA. At a key branchpoint, the presence/absence of flavonoid-3',5'-hydroxylase (F3'5'H) or flavonoid-3'-hydroxylase (F3'H) leads to the production of different anthocyanin compounds. Delphinidin requires the presence of F3'5'H. Another major anthocyanin, cyanidin, requires F3'H while pelargonidin requires the absence of F3'5'H and F3'H. Daylilies may not have a blue color because F3'5'H is absent or is a pseudogene. Lack of the blue color could also be due to overxpression of regulatory MYB genes. In this study, genes for enzymes of the anthocyanin biosynthetic pathway were amplified using PCR. The PCR DNA was then cloned and sequenced. A DNA fragment of the putative gene for F3'5'H was found.