Flower color modifications of Torenia hybrida by cosuppression of anthocyanin biosynthesis genes

White and blue/white varieties of Torenia hybrida were successfully obtaine d from the blue variety cv. Summerwave (SWB) by cosuppressing expression of two of the genes involved in anthocyanin biosynthesis; chalcone synthase ( CHS) and dihydroflavonol 4-reductase (DFR). Such molecular breeding is the only precise and efficient way to create flower color variation in SWB due to its male and female sterility. Flower color and the degree of suppressio n varied between transgenic lines, and anthocyanin biosynthesis was more co nsistently suppressed in the dorsal petal lobes, ventral petal lobes and co rolla tube than lateral petal lobes. A pink variety was obtained by cosuppr essing the flavonoid 3',5'-hydroxylase (F3'5'H) gene. Yellow torenia was ob tained from T-33, an in-house cultivar that contained both carotenoids and anthocyanins, by cosuppression of CHS or DFR genes.