Anthocyanin biosynthesis in gerbera cultivars Estelle and Ivory

The acyanic cultivar Ivory is a sport of the pelargonidin containing pink cultivar Estelle, i.e., it originates from an acyanic branch of Estelle. To elucidate the flower pigments missing in Ivory, we collected samples from different developmental stages of Estelle and Ivory whole flowers and epidermi for anthocyanin analysis using Ultra-performance liquid chromatography tandem mass-spectrometry (UPLCMS/MS) and for RNA sequencing using the Illumina method. According to UPLC-MS/MS, we observed that Ivory lacked pelargonidin but had higher amounts of kaempferol glycosides. Apigenin glycosides were at similar levels as in Estelle. According to EST and Illumina sequencing data, we perceived that all anthocyanin biosynthesis genes were expressed similarly in the two cultivars. However, we found two allelic pairs (i.e., two loci) of the Dihydroflavonol 4-reductase (DFR) gene in Estelle and Ivory, and one of them carried in Ivory a single base mutation leading to amino acid change in the substrate binding site