| 摘要: | 帝王花Protea cynaroides 對國際花卉栽培市場而言是重要的切花產品，目前，多數的切花均自野 外取得，然而，過度和任意地摘採將造成環境的破壞與其野外數量的削減。野外取得的切花之品質往往 不一致且差劣，而帝王花農場的建立則受限於栽植的困難。為確定帝王花基因之一致性，常利用其扦插 苗於田間種植，但帝王花生長極慢，一般需6個月的時間才能發根，且常發生發根不一致和發根率低之 現象。本研究之目的即在發展光自營微繁殖系統以生產性狀一致且可馴化之帝王花苗。 本研究中將取盆植植栽之莖部作為外植體，腋芽以增殖培養基誘發幼芽增殖，微幼芽再以無糖之 MS培養基（含 1 mg L-1 NAA）培養。結合不同支撐材料（如：蛭石、珍珠石及粗砂）、多酚類和KH2PO4 (0; 50; 100; 300 mg L-1) 將用作培養基以探討其對微幼芽之生長及發根之影響。所有的幼苗將培養於富含 CO2 (500; 750; 1000; 2000 μmol mol-1)並以紅光 (660 nm)、紅加藍光 (450 nm) 或遠紅光(730 nm) LED照 射之光自營環境中，以促使幼苗在解剖及生理上之生長足以有效地進行光合作用並存活於試管外之條件 中，其所產生之帝王花苗將進而移至試管外之環境中馴化，並以上述三種光源刺激其根與葉之形成且改 善其存活率。實驗後評估各種處理中根與葉之生長、淨光合作用速率、葉綠體含量及幼苗葉片之Rubisco 活性。
Protea cynaroides L. is an important cut flower in the international floriculture market. Currently, the majority of cut flowers are harvested from the wild. Over- and indiscriminant harvesting has led to widespread destruction of the environment and reduction in wild stocks. Cut flowers harvested from the wild are often of inconsistent and poor quality. As a result, fluctuations in the supply of quality cut flowers are a common occurrence. Establishment of commercial P. cynaroides plantations is limited due to the difficulties faced by growers. To ensure genetic uniformity, rooted stem cuttings are used to establish P. cynaroides plants in the field. However, rooting of stem cuttings generally take 6 months, while inconsistent rooting and low rooting percentages are often observed. Furthermore, P. cynaroides is an extremely slow-growing plant, and have unique nutritional requirements, which are difficult to manage. Micropropagation is often used to propagate slow growing or difficult-to-root plants. The aim of this study is to develop a photoautotrophic micropropagation system from which genetically uniform P. cynaroides plantlets can be rooted and successfully acclimatized. In this research, explants will be established from nodal stem segments taken from pot plants. Axillary buds will be transferred to multiplication media to induce shoot proliferation. Microshoots will then be cultured in sugar-free MS media supplemented with 1 mg L-1 NAA. Different porous supporting materials such as vermiculite, perlite and coarse sand, in combination with reduced concentrations of KH2PO4 (0, 50, 100, and 300 mg. L-1) and phenolic compounds (3,4-dihydroxybenzoic acid, salicylic acid and gallic acid), will be included in the growth media to study their effects on the growth and rooting of P. cynaroides microshoots. All plantlets will be cultured photoautotrophically with CO2 enrichment (500; 750; 1000 and 2000 μmol mol-1) irradiated with red (660 nm), red+blue (450 nm) or far-red (730 nm) LEDs. The use of photoautotrophic cultures is designed to stimulate the growth of plantlets that are anatomically and physiologically competent, are able to photosynthesize efficiently, and survive in ex vitro conditions. P. cynaroides plantlets produced photoautotrophically will be transferred to the ex vitro environment for acclimatization. The plantlets will be grown in perlite or a mixture of peat and sand (1:1; v:v) in a greenhouse, while three types of LEDs (red, red+blue and far-red) will be used as the light source to induce the formation of new roots and leaves, and improve their survival rate. Growth of roots and leaves, and the net photosynthetic rate, chlorophyll content and Rubisco activity of plantlets’ leaves will be measured in all treatments. Histological studies of stomata in plantlet leaves will be carried out, and comparisons between in-vitro-cultured and acclimatized plantlets will be made.Protea cynaroides L. is an important cut flower in the international floriculture market. Currently, the majority of cut flowers are harvested from the wild. Over- and indiscriminant harvesting has led to widespread destruction of the environment and reduction in wild stocks. Cut flowers harvested from the wild are often of inconsistent and poor quality. As a result, fluctuations in the supply of quality cut flowers are a common occurrence. Establishment of commercial P. cynaroides plantations is limited due to the difficulties faced by growers. To ensure genetic uniformity, rooted stem cuttings are used to establish P. cynaroides plants in the field. However, rooting of stem cuttings generally take 6 months, while inconsistent rooting and low rooting percentages are often observed. Furthermore, P. cynaroides is an extremely slow-growing plant, and have unique nutritional requirements, which are difficult to manage. Micropropagation is often used to propagate slow growing or difficult-to-root plants. The aim of this study is to develop a photoautotrophic micropropagation system from which genetically uniform P. cynaroides plantlets can be rooted and successfully acclimatized. In this research, explants will be established from nodal stem segments taken from pot plants. Axillary buds will be transferred to multiplication media to induce shoot proliferation. Microshoots will then be cultured in sugar-free MS media supplemented with 1 mg L-1 NAA. Different porous supporting materials such as vermiculite, perlite and coarse sand, in combination with reduced concentrations of KH2PO4 (0, 50, 100, and 300 mg. L-1) and phenolic compounds (3,4-dihydroxybenzoic acid, salicylic acid and gallic acid), will be included in the growth media to study their effects on the growth and rooting of P. cynaroides microshoots. All plantlets will be cultured photoautotrophically with CO2 enrichment (500; 750; 1000 and 2000 μmol mol-1) irradiated with red (660 nm), red+blue (450 nm) or far-red (730 nm) LEDs. The use of photoautotrophic cultures is designed to stimulate the growth of plantlets that are anatomically and physiologically competent, are able to photosynthesize efficiently, and survive in ex vitro conditions. P. cynaroides plantlets produced photoautotrophically will be transferred to the ex vitro environment for acclimatization. The plantlets will be grown in perlite or a mixture of peat and sand (1:1; v:v) in a greenhouse, while three types of LEDs (red, red+blue and far-red) will be used as the light source to induce the formation of new roots and leaves, and improve their survival rate. Growth of roots and leaves, and the net photosynthetic rate, chlorophyll content and Rubisco activity of plantlets’ leaves will be measured in all treatments. Histological studies of stomata in plantlet leaves will be carried out, and comparisons between in-vitro-cultured and acclimatized plantlets will be made. |
