Water lettuce (Pistia stratiotes L.) is a free-floating perennial herbaceous plant with rosette leaves and a stem. Although this plant multiplies and has adverse effects on aquatic ecosystems, it can be used for biological purification of polluted water and production of valuable substances as a traditional medicine. In this study, we report a protocol to establish an in vitro micropropagation method based on direct shoot organogenesis from stem explants. In media comprising two types of basal medium and different growth regulators, multiple shoot organogenesis was observed on stems. The micropropagation method was most effective on Schenk and Hildebrandt (SH) medium with 1 mg/L indole-3-acetic acid and 2 mg/L 6-benzylaminopurine supplemented with 30 g/L sucrose, on which all explants produced multiple shoots. The shoots rooted spontaneously on solid half-strength Murashige and Skoog (MS) and SH media without growth regulators (1/2MSO and 1/2SHO). However, roots developed more vigorously in liquid media. Regenerated plants colonized and grew more rapidly in SH basal medium than in MS basal medium and produced 6–8 stolons within 2 weeks on 1/2SHO. In summary, we established a method for micropropagation in vitro through direct organogenesis of water lettuce, which shows the potential of water lettuce as a model aquatic plant for phytochemical and pharmacological research.

이전 실험에서 결정된 생육 단계별 최적 환경조건을 평가하기 위한 4가지 처리는 다음과 같았다: 생육 단계별 최적 환경 조건을 사용한 광독립 영양배양(photoautotrophic optimum condition with growth stage (POG)), 생육 단계별 평균 광합성 광량자속 밀도(photosynthetic photon flux density(PPFD))와 CO2 농도를 사용한 광독립 영양배양(photoautotrophic constant condition with average PPFD and CO2 of POG(PCA)), 생육 단계별 최대 PPFD와 CO2농도를 사용한 광독립 영양배양(photoautotrophic constant condition with maximum PPFD and CO2 of POG(PCM)) 그리고 대조군으로 3%의 당을 포함한 광혼합 영양배양(photomixotrophic conventional condition with 3% sucrose(PMC)). 실험 결과 각 생육 단계별 환경제어(POG)는 기내에서 배양된 감자 소식물체의 모든 생육 관련 항목에서 유의적 증진을 유도하였다. 또한 단위 건물중 당 소비된 전력과 CO2는 모든 처리 중 POG에서 가장 낮았다. 기외 이식 이후에도 POG에서 생산된 감자 묘는 PMC에서 자란 감자 묘와 전체적으로 큰 차이 없이 왕성한 생육을 유지하였다. 특히 POC는 기존 광혼합 영양방식(PCM)과 비교했을 때 기외 이식전과 이식 후 20일째 각각 4.7배와 3.8배 높은 건물중을 기록하였다. 따라서 POG와 같은 생육 단계별 환경 조절을 통한 광독립 영양 미세 증식 방법은 에너지 절감 효과와 함께 무균의 건강한 감자 묘의 생산에 효과적이었다.

Cryopreservation is one of the ideal and suitable methods for long-term storage of plant germplasm. The plant contaminated with diseases and pathogens are decreased the multiplication rate, survival rate and high quality of plants after cryopreservation. The aim of this work was to improve a micropropagation method for lily in Korea, which is indigenous plant. In the last process of rinsing scales after surface-sterilization, we tried to control the diseases and pathogens lived within the tissue by rinsing in 0.03% sodium hypochlorite (NaClO) instead of sterile distilled water. Bulb scales of Lilium were cultured in vitro on MS medium supplemented with Plant Preservative Mixture (PPM). The results showed that L. tsingtauense accessions were observed ranged from 53.9 to 100% with a mean value of 76.8% and L. hansonii accessions were checked from 84.5 to 85.5% with a mean of 85% survival rate. The newly small bulb formed from bulb-scales was transferred to MS medium. We checked the presence of microorganisms and survival rate after 3 weeks in culture after examination of bacterial incidences. The results indicated that the non-contamination rate were shown ranged from 75.0 to 94.1% with mean value of 83.2% in L. tsingtauense species, and that L. hansonii were observed 85.1 to 91.7% with mean value of 88.4%. This study will provide a valuable basis for establishment of effective axenic cultures for in vitro micropropagation of Korean native lily species.

Background : Cnidium officinale Makino is a perennial herb of the family Umbelliferae, and an important traditional oriental medicinal plant in China, Japan and Korea. Cnidii Rhizoma, the dried rhizome of C. officinale have been used as traditional oriental medicine in Korea. It has been shown that the cnidii rhizomes are used in the treatment of pain, inflammation, menstrual disturbance, and anti-vitamin deficiency disease, and also act as a blood pressure depressant. In this study, we anticipated to establish the mass propagation system of C. officinale, which is a high economic value as medicinal herb, by plant tissue culture to solve the problem of root stocks contamination. Methods and Results : The whole study was carried out in the department of Herbal crop research, Eumseong, RDA. In this study, C. officinale root bud was used as a explant and it was surface sterilized by 1% sodium hypochlorite for 3 minutes, then several times washed with ddH2O. Multiple shoots were induction them on MS, B5, SH media with 0.1 - 2 ㎎/ℓ auxin (NAA, IBA) and cytokine (BA, Zeatin). In this study we obtained, 7.4 multi-shoots per an explant, and the shoot growth was also favorable in the presence of 0.2 ㎎/ℓ Zeatin. Subsequent transfer of these regenerated shoots on 1/2 SH media resulted in root formation. Rooted plantlets were able to grow in soil after a short period of acclimatization. Conclusion : This experiment was comducted to identify the optimal in vitro propagation condition of C. officinale.

Shoot tips of chinese yam (Dioscorea opposita Thunb.) were cultured on MS medium containing 0.5 mg/L BA to produce micro-tubers in vitro. To stimulate the formation of shoots and micro-tubers, and produce large micro-tubers, the sections of micro-tubers were cultured on MS media with BA and IAA. The shoot multiplication, and the micro-tuber formation and growth were very effective on the media containing 2.0 mg/L BA and 0.5~1.0 mg/L IAA. Sucrose added to MS medium with 2.0 mg/L BA and 0.5 mg/L IAA to stimulate more micro-tuber growth. The medium added 50 g/L sucrose was very effective in the increase of plant fresh weight and micro-tuber growth. After 4 weeks' culture of micro-tuber sections on the medium with 2.0 mg/L BA, 0.5 mg/L IAA and 50 g/L sucrose, the liquid media were added into the same vessels. The micro-tuber growth was stimulated remarkably by the addition of liquid medium. The addition of 25 ml liquid medium containing 10 g/L activated charcoal, 3x MS salts and 250 g/L sucrose was the most effective in micro-tuber growth.

유색 칼라 세 품종(Sunlight, Chiante, Pink Persuation)의 기내 급속증식체계를 확립코자 정단분 열조직을 배양함에 있어 callus, 신초 및 뿌리 분화에 미치는 식물생장조절물질의 효과와 sucrose가 기내 괴경 형성 및 비대에 미치는 효과를 조사하였다. 식물체는 캘러스를 통하거나 또는 치상체에서 직접 분화되는 두 경로로 형성되었으며 2.0 mg/L BA 단용 처리에서 Sunlight품종은 53.3% 캘러스를, Chiante 품종은 56.7% 직접 신초를 형성하였다. 2.0-3.0 mg/L BA 단용 처리는 품종별로 식물체재 분화 빈도가 20-70%로 차이가 있었으나 세 품종 모두 3.0 mg/L. BA 단용 처리에서 신초 분화가 양호하였다. 다아체 형성에 미치는 cytokinin의 효과는 Sunlight품종은 1.0 mg/L 2ip 처리로 16개체를, Chiante 품종은 5.0 mg/L BA를 처리로 14개체를, Pink Persuasion품종은 1.0 mg/L BA처리로 12개체를 형성하였다. NAA는 세품종 뿌리분화에 효과가 없었으며 Sunlight 와 Chiante 품종은 1.0 mg/L IAA에서, Pink Persuasion 품종은 2.0 mg/L IBA가 효과적이었다. 괴경형성에 미치는 sucrose는 Sunlight 품종은 90 g/L, Chiante 및 Pink Persuasion 품종은 70 g/L 가 괴경 형성 및 비대에 효과적이었다.