植物生長調節劑對臺灣一葉蘭體胚形成之影響

Effect of Plant Growth Regulators on Somatic Embryo Formation in ＂Pleione formosana＂

臺灣一葉蘭（Pleione formosana Hayata）為臺灣原生的蘭花，現已有本土選育之優良品種但亟需大量繁殖供應市場需求。將‘梅雪’及‘楓星’一葉蘭第四芽培養再生之叢生芽分切為次級培植體，於含不同NAA與BA濃度的1/2 MS培養基中培養8週後，可成功誘導出體胚，以0.2mg．L^(-1)NAA+0.4mg．L^(-1)BA處理的存活率及體胚數最多。誘導出的體胚形態及發育過程與播種產生的一葉蘭原球體類似。尚未見鞘葉的體胚繼代於含不同生長調節劑濃度的1/2 MS培養基中，培養8週後可繼續增生出新的體胚，‘梅雪’以0.2、0.4mg．L^(-1)NAA組合BA比2, 4-D組合BA之處理更能促進體胚成熟，‘楓星’則以0.4mg．L^(-1)NAA組合0.4mg．L^(-1)BA處理有最高的體胚數及體胚成熟率。本研究結果顯示，‘梅雪’及‘楓星’一葉蘭培養於添加0.2、0.4mg．L^(-1)NAA組合BA的1/2 MS培養基中可直接體胚發生，初級體胚繼代後可繼續增生次級體胚。 Pleione formosana Hayata (Orchidaceae) is a Taiwan-native orchid. New and excellent domestic cultivars have been bred and released, but rapid mass propagation is required to meet market demand. In this study, multiple shooting regenerated from the fourth bud culture were divided as secondary explants, and cultured for 8 weeks on 1/2 MS medium supplemented with NAA and BA combinations. Somatic embryos (SEs) were successfully induced and those cultured on 0.2mg．L^(-1) NAA combined with 0.4mg．L^(-1) BA induced more SEs formation. Induced SEs had growth phase similar to seed-developed protocorms. SEs without visible sheath leaf were further cultured for 8 weeks on 1/2 MS medium supplemented with plant growth regulators (PGR). New SEs were successfully induced, and NAA was more efficient than 2, 4-D in SE maturation of 'Mei Snow'. Whereas 'Feng Star' had the highest SE number and SE maturation when cultured with 0.4mg．L^(-1) NAA combined with 0.4mg．L^(-1) BA. This research revealed that Pleione formosana 'Mei Snow' and 'Feng Star' cultured in 1/2 MS medium supplemented with 0.2, 0.4mg．L^(-1) NAA and BA combinations could induce direct somatic embryogenesis. Primary SE could regenerate secondary somatic embryos after sub-culture.