A New Rose of Sharon Cultivar, “Seonnyo” Developed by Mutation Breeding

“Seonnyo” is a new Hibiscus variety developed by mutation breeding using gamma ray irradiation at Korea Atomic Energy Research Institute (KAERI). One hundred seeds of original variety, “Gyewolhyang”, collected in Namyangju of Gyeonggi Province were irradiated 10 Krad ã-ray from a ⁶⁰Co source at KAERI in 1993 (Fig. 1). The original variety, “Gyewolhyang” showed the I-c that means single and bell-shaped flower type, and light purple with small red eye in its flower color. The irradiated seeds were sown in a field of the Atomic Experiment Farm in Namyangju, in April 1994. Forty-four out of one hundred seeds survived. Among them one tree was selected as a mutant, “Gyewolhyang S-10-1” (whose meaning is one mutant from 10 Krad irradiated seeds) in 1996. Propagation of the mutants by means of cuttings and characterization were done during 1997 to 2001, and then tentatively named “Weonnong 14” to the final selected-mutant. The leaf traits of mutant except for length of leaf were larger than those of original variety (Table 1). The size of flower and pistil were larger than those of the original variety (Table 2). The flowers showed light violet from center to edge, but the flower color of light violet gradually turned into whitish by the beginning of aging, in September. In particular, the red eye in the original variety turned into white in the new variety. Also, a new variety has the flower type, I-b, was a different from the original variety. The name of the new variety, “Seonnyo” reflects its white flower color (Fig. 2).