白玉蘭及洋玉蘭微體繁殖之研究

Abstract

白玉蘭（Michelia alba DC.）莖頂約0.15-0.3 mm為最佳取材大小，以 BA、kinetin、2ip、Fulmet及TDZ不同濃度處理下培養30天，各成活率均 近於 100﹪，其中BA處理之培植體有較佳之生長情況。若不添加任何生長 調節物質，培植體存活率低。培養基1/2MS添BA 2 mg/l與IBA 0.05 mg/l 之處理組合最適合莖頂初代培養；而 BA 0.5 mg/l、NAA 0.05 mg/l及 BA 1 mg/l、 NAA 0.1 mg/l 處理， 雖有良好之生長量，但培植體趨於 黃化。 此外， adenine sulfate及 GA3之添加並無促進生長效果，反而 導致生長量下降，癒傷組織及褐化現象的產生。不同培養基鹽類濃度試驗 中以1/2MS最適合莖頂初代培養，於MS濃度培養時，癒傷組織量增多，而 WPM及1/4MS培養之培植體色澤濃綠且生長緩慢；經初代培養後，以 MS培 養可促進培植體之生長。莖頂液體振盪培養，則以振盪 14天之培植體無 水化現象，並可獲得較好之生長量及側芽生長，而雙相培養時，芽體之蓋 狀托葉雖可脫落， 但多數有癒傷組織的產生，於固相培養基生長之培植 體生長則非常緩慢；當芽體於8 mm大小時，以GA3處理對培植體拉長生長 並無效果。白玉蘭2-3 cm頂梢，以MS添加BA 2 mg/l及蔗糖30 g/l培養， 可使蓋狀托葉開裂與芽體正常生長， 且將培植體植於雙相培養基中培養 則可提高增殖率；於枝條上，取不同節位側芽培養，則以基部節位側芽生 長勢較強。在癒傷組織誘導方面，不同濃度 2,4-D及kinetin組合處理時 ，頂梢培植體於 kinetin 2 mg/l、2,4-D 0.2 mg/l，花瓣組織於 2,4-D 0.4 mg/l及 kinetin之各種濃度下，子房則以2,4-D 0.4 mg/l及 kinetin 0.5 mg/l時，均可誘導出淡綠色之癒傷組織，而在雄蕊培植體培 養上， 則大部分死亡。洋玉蘭 （Magnolia grandiflora Linn.）莖頂初 代培養，於不同濃度BA處理下，培植體可達90-100﹪之成活率，其中以 BA 0.5 mg/l處理之培植體生長量最高，當再加入IBA不同濃度處理時，培 植體之褐化及死亡率增高；初代培養後，莖頂培植體於固態培養基中培 養210天，少數培植體有大於2 mm之側芽生長。

Apical shoots, with 0.15-0.3 mm size were found to be the best explants for shoot regeneration of white Michelia (Michelia alba DC.). These explants were cultured on 1/2MS medium supplemented with BA, kinetin, 2ip, Fulmet or TDZ for 30 days. In general, medium supplemented with BA showed the best results for explants growth. On 1/2MS medium supplemented with BA and IBA, maximum growth induction from explants occurred on 2 mg/l BA with 0.05 mg/l IBA, while 0.5 mg/l BA and 0.05 mg/l NAA or 1 mg/l BA and 0.1 mg/l NAA treatments with higher growth effects on media. The best growth were achieved when shoot apies cultured on the paper bridge medium with 1/2MS salt strength containing 2 mg/l BA 0.05 mg/l IBA and 30g/l sucrose for 30 days. A better growth response and axillary shoot elongation were observed in shake culture-grown shoot tip explants. Healthy shoots developed within 60 days in solid medium culture. Double- phase static cultures showed elongation of shoots with a low muitiplication rate and poor shoot growth. Terminal shoot cultures were established on MS medium supplemented with 2 mg/l BA and 30 g/l sucrose , bud breaking and cap-like stipules rupturing were observed in first 1-2 week culture. After initial culture of bud explants transferred to double-phase medium were found to be the best for axillary shoot multiplication. When the medium contained 2 mg/l kinetin, light green calli were induced on the terminal shoots base. Similar induction was observed in the presence of 0.4 mg/l 2,4-D combined with 0.5 mg/l kinetin on ovary cultures. Successful survial was obtained with the utilization of shoot tip explants of Magnolia grandiflora , about 100﹪of these explants were able to survive in 1/2MS media with BA alone but no in combination with IBA.