蝴蝶蘭花芽誘引和花序發育時之碳水化合物變化

Changes in Carbohydrates in Phalaenopsis during Flower Induction and Inflorescence Development

白花蝴蝶蘭1-2年生成熟植株，於仲夏高溫營養生長期，給予日／夜溫25/20℃涼溫誘引開花。且在催花前的營養期、花梗抽出期、花梗伸長到10-15cm及花苞可見4期，各別取成熟葉片、莖，花梗及根部分析其所含澱粉、蔗糖及葡萄糖含量，並以光學顯微鏡切片觀察花芽分化。涼溫（25/20℃）催花3星期花梗剛露出0.5-1cm時，花芽尚未分化，屬花芽誘引期；此時各葉片之澱粉含量下降，蔗糖濃度增加。花梗長3.5cm時著花處之苞葉已分化，至花梗伸長15cm時已具有7朵花苞及花原體，此時花梗主要成分為可溶性糖，莖主含蔗糖，是運輸蔗糖的通道，而根在花梗伸長時所含碳水化合物高於營養生長期，顯求涼溫催花時養分由葉轉換到花梗及根部。作者分析探討其花芽誘引，認為相當符合氏Bernier等人之多因子控制學說。

Mature white Phalaenopsis plants grown from seedlings or clone at vegetative phase in mid-summer were induced flowering after forcing in phytotron at day/night temperature 25/20℃. Carbohydrate contents in individual mature leaves, stems, elongating flower stalks and roots were analyzed at 4 stages: vegetative stage at high temperature, flower stalk emeraged after cool induction for 3 weeks, elongating flower stalk 10~15 cm in length, and flower bud visible. Morphology and anatomy of axillary buds and floral initiation and development were also observed by light microscope. After cool induction, the flower stalk emerged 0.5~1.0 cm in length, and no flower bud primordium was observed. Flower bud initiation started when flower stalk reached 3.5 cm in length and 7 flower buds and primodia were formed when flower stalk 15 cm in length. The starch content in mature leaves decreased and sucrose concentration increased during flower induction. The sucrose and soluble sugars were the major content of carbohydrates in stem and flower stalk respectively. The carbohydrate content in root at bud visible stage Was higher than the content at vegetative phase. It showned that perception of cool temperature induction by mature leaves, mobilization the carbohydrate in leaves and followed transport of sucrose in stem to the mature buds and roots. The results of this study showed the evidence to the floral induction of Phalaenopsis agree with the theory of multifactorial control postulated by Bernier's.