Hibiscus syriacus 'Dasom', A New Flower-Color Mutant Variety Developed by Radiation Breeding

A new Hibiscus syriacus variety, 'Dasom', was developed by radiation breeding using gamma ray exposure at the Korea Atomic Energy Research Institute (KAERI). Seeds of the original variety, 'Hongsun', were collected in 1993. These seeds were irradiated at 100 Gy dose and $M_1$ seeds were planted in a field of the KAERI in 1994. Lines with preferred flower color that were going to be used for street trees were initially selected in 1998. Analyses of characteristics were conducted from 2005 to 2010. The 5-year-old 'Dasom' plants were approximately 106 cm in height and averaged 19 branches, and thus were suitable for street trees. The flowers of 'Dasom' were semi-double type with medium red color and red eye spots. Petal length and width were about 4.0 cm and 3.3 cm, respectively. Flower diameter was slightly small, at about 5.8 cm, because of highly overlapping petals. The flowering period of 'Dasom' was about 105 days, which was 6 days shorter than that of the original variety, 'Hongsun'. However, the main charactersistics of 'Dasom' including leaf shape were similar to those of the original variety, 'Hongsun'.

방사선 육종에 의한 화색변이 무궁화 신품종 '다솜' 육성

무궁화 '다솜'은 1993년에 채종한 '홍순' 종자를 이듬해에 한국원자력연구원 감마선 저준위조사시설에서 감마선 100Gy를 조사하여 1998년에 가로수용으로 유망한 우수한 화색을 가진 개체를 1차 선발하였다. 2005년부터 2010년까지 6년에 걸쳐 선발 계통의 균일성과 안정성을 검정하였다. 무궁화 '다솜'의 주요특성으로 초장은 106cm로 길며, 분지수는 19개로 많은 편이고 가지는 상향으로 갈색을 띈다. 꽃은 홍단심계 반겹꽃으로 옅은 적색을 띄고, 꽃잎의 길이(4.0cm)와 폭(3.3cm)은 중간 정도이나 꽃잎의 겹침 정도가 강하여 전체적인 꽃의 직경(5.8cm)은 다소 작은 편이다. 개화시간은 17시간 정도로 다른 품종들과 유사하나, 개화일수는 105일로 대조품종인 '홍순'(111일)에 비해 짧은 편이다. 잎의 모양을 비롯한 주요 특성은 '홍순'과 유사하다.