“…Thus, attenuated Cclass function could increase petal development, inhibit stamen development, and also increase the floral organ number, which is consistent with the formation of double flowers. Double-flowered phenotypes result from C-function repression in a number of horticultural plants, including Gentiana scabra (Nakatsuka et al, 2015), Camellia japonica (Sun et al, 2014), Petunia hybrida (Noor et al, 2014), and Cyclamen persicum (Tanaka et al, 2013). Therefore, it is likely that the double flowers of Japanese azalea cultivars result from lost or impaired C-function genes.…”