鳳蘭之無菌發芽

In Vitro Germination of Cymbidium Dayanum

取鳳蘭（Cymbidium dayanum）自授粉後八個月青果莢內之種子，於0.5% NaOCl溶液中消毒5、10及15分鐘均完全死亡，而不消毒無菌播種者均可發芽，顯示鳳蘭無菌播種宜避免直接消毒種子。最適合種子發芽的基本培養基1/2MS+30g/l 蔗糖+2g/l活性碳。添加有機物如椰子水15%（v/v）或香蕉泥150g/l，可大為提高種子的發芽速率及小苗生長勢，並可避免於原球體階段褐化死亡，胺基酸arginine 1mM亦有促進發芽及防止原球體褐化作用，而培養基中不添加活性碳，則種子無法發芽。

The effects of medium composition on in vitro germination and developmental process were studied in orchid Cymbidium dayanum. Seed and germinating process were also observed under light and scanning micrograph. Seeds inside capsules were harvested 8 months after pollination could not survive in 0.5% NaOCl solution for 5, 10 and 15 minutes. Therefore seed sterilization should be avoided. The suitable basal medium was half strength MS salts with 3% sucrose. Activated charcoal was necessary for seed germination. Organic additives of coconut water 15%, banana homogenate 150g/l and tryptone 3g/l could promote seed germination and seedling growth and eliminate protocorm browning during embryo development. Arginine 1 mM also substantially promoted seed germination and prevented protocorm browning in germination of Cymbidium dayanum.