An efficient plant regeneration protocol is developed for a standard-type chrysanthemum. When petal segments derived from flower buds (4 or 8cm in diameter) were used as the culture material, the highest shoot regeneration frequency (96%) was obtained on a Murashige and Skoog (MS) medium supplemented with 0.5 mg/L IAA, 2 mg/L BA, 3% sucrose, and a 0.8% agar. Pre-culturing the explants under dark conditions for 14 days produced better results for the shoot regeneration frequency than the explants cultured under a continuous 16 h photoperiod (40 μmolm-2 s -1 ). The shoot regeneration frequency ranged from 19.0% for the Shinmato cultivar to 89.1% for the Baeksun cultivar. Activated charcoal (0.2%) enhanced the root formation of the regenerated shoots in a hormone-free MS medium. The rooted plantlets were acclimatized and successfully established in a greenhouse.

As the increase of chrysanthemum demand on chrysanthemum increases in Korea, the production of high quality chrysanthemum is needed. Chrysanthemum stunt viroid (CSVd) is one of the important viroid, which infects chrysanthemum and induces diseases that affects the decrease of quality and yield. To solve this problem, we used different size of meristem of chrysanthemum ‘Ency’ for shoot tip culture and also that of combined with heat treatment at 37οC. The efficiency of CSVd elimination was influenced by the size of shoot tip. The small-sized of meristems with 1 or 2 leaf primodia were regenerated into the highest number of CSVd-free plantlets. By RT-PCR, the 214-bp band corresponding to CSVd was not detected in 22.2% of the total number of tested regenerants from shoot tips with 2 leaf primordia. While, shoot tip culture combined with heat treatment of one-month-old in vitro shoots was not effective for CSVd-elimination. The CSVd-free plants grew more vigorously than CSVd-infected plants in the greenhouse.

본 연구는 우리나라 주요 재배종인 Muscari armeniacum ‘Early Giant’ 품종을 사용하여 엽절편체로 부터 직접적으로 신초재생과 체세포배 발생에 미치는 생장조절제의 효과를 구명하였다. 무스카리의 엽조직으 로부터 캘러스 과정을 거치지 않은 직접 신초형성은 2,4-D 0.1 mg·L−1가 함유된 배지에서 가장 좋았다. 반면, 체세포배 발생은 생장조절제를 첨가하지 않는 대조구와 IPA 0.1~1.0 mg·L−1가 함유된 농도의 배지에서 비교적 양호하였다. 무스카리의 엽조직으로부터 재생된 자구를 기외로 이식했을 때 맹아율은 모든 처리구에서 80%이상 으로 높았으며 특히 NAA 0.1mg·L−1, IPA 1.0~3.0mg·L−1 배지에서 재생된 자구의 생장이 양호하였다.