蓮霧芽體形態發育之研究

Studies on Bud Morphogenesis in Wax-apple (Syzygium Samarangense Merr. et. Perry)

蓮霧枝梢成熟前，在每對葉腋基部發育成三個斜列的複合腋芽。隨著梢齡增加及葉片脫落後，在葉痕上方的潛伏芽會有次級腋芽發生，但伸長活性低。枝梢屬於多樣性的生長形態；枝條及葉片的長、寬度皆呈單S型生長曲線；枝梢上芽體萌枝（花）的能力，以各梢次芽鱗痕留下的潛伏芽及頂芽的比例較高，而帶葉片的腋芽萌枝（花）的比例較低。蓮霧浸水前及初期（七月中、下旬及八月上、中旬），潛伏芽體仍呈營養態，俟浸水約一個月左右（八月中、下旬及九月上旬），部份芽體已進入呼喚期階段。九月上、中旬迅速形成具分枝的花序原體。九月中、下旬及十月上旬以後，小花原體及分枝原體迅速發育，而後花器依萼片、花瓣、雄蕊、雌蕊順序形成。由花器附屬組織包圍子房形成的子房下位花，於十一月上旬左右綻放。

Axillary bud primordia of wax-apple differentiated from the epidermal and the sub-epidermal cells located at the adaxial side of the stem apex. Two other buds were added on each axillary bud of the maturing current shoots. Most of the axillary buds did not sprout and became latent buds. More sub-axillary buds were differentiated on each leaf trace and developed into group of latent buds. A manifold growth habit was noted in wax-apple and sigmoid growth curve in stem or leaf. The basal latent buds without leaf attached and the terminal buds had higher percentage of flushing and flowering than the axillary buds with leaf attached. The latent buds were in vegetative stage and characterized by two obvious tunica layers, slowgrowing rib meristem, and many pairs of leaf primordia. No sign of reproductive growth in these buds was noted prior to or at the beginning of flooding. However, some buds had entered the evocational period after one month of flooding and the meristematic activity in the buds increased, the zonation disappeared, and the axillary meristem initiated and elongated precociously. The enhanced activity resulted in the sprouting of the latent buds and the formation of the inflorescence primordia. Floret primordia initiated acropetally on each inflorescence but basipetally on each cyme unit. Sepals, petals, stamens, and pistils initiated sequentially on each floret primordium. The epigynous flower was composed of ovarian tissue, hypanthium and appendicular tissues.