聖誕紅經由懸浮培養之體胚形成

Somatic Embryogenesis of Poisettia through Suspension Culture

本試驗以'Nobel Star'和'Picacho'聖誕紅為材料，利用莖段癒傷組織建立細胞懸浮培養。當懸浮細胞培養在含0.2 mg/l 2，4-D與0.2 mg/l BA或含0.2 mg/l 2，4-D與1 mg/l BA之全量MS培養基中，有最多的細胞增殖。而當懸浮細胞培養在含0.2 mg/l 2，4-D與0.2 mg/l BA之全量MS培養基中，有最高的胚性細胞形成率。胚性細胞形狀較圓而小，細胞核大、細胞質稠密，經aceto-carmine染色後具有螢光性。培養基中含0.05 mg/l BA和1 mg/l ABA有助於體胚之成熟，但大多數的胚到達球形期或心臟期即停止進一步發育。將培養於未含ABA培養基之體胚平板培養後易形成癒傷組織，且由此癒傷組織可再生二次體胚與不定芽體。

Stem segments of poinsettia (Euphorbia pulcherrima) cultivars, Nobel Star and Picaccho, were used for establishing the suspension culture. Calli cultured in the full strength MS base liquid medium containing 0.2 mg/l 2, 4-D and 0.2 mg/l BA had the largest packed-cell volumes of propagation. And the media containing 0.2 mg/l BA and 0.2 mg/l 2, 4-D had the highest regenerating rate of embryogenic cells. Embryogenic cells are small and round, with large nuclei and dense cytoplasm. There were fluorescent after staining with acetocarmine. Non-embryogenic cells are large and oblong, with small nuclei and large vacuoles and no fluorescence observed after staining. Liquid medium 0.05 mg/l BA and 1 mg/l ABA improved the maturation of somatic embryos. However, embryos usually stopped developing after reaching the globular or the heart-shaped stage. After plating, callus formed on embryo, which was not cultured with ABA. This callus tissue subsequently differentiated into a secondary somatic embryo and adventitious shoot subsequently.