豬籠草捕蟲袋之組織解剖觀察

Histological Studies of Pitcher in the Nepenthes alata Blanco

豬籠草為熱帶食蟲植物，其葉先端中脈變形為捕蟲袋，能捕獲昆蟲將之消化。本研究以實體顯微鏡、光學顯微鏡及掃瞄電子顯微鏡觀察捕蟲袋的組織形態。發現捕蟲袋蓋內部表面佈滿蜜腺，皮層中也有蜜腺規則分佈，蜜腺由似柵狀組織細胞組成，並有維管束相連其袋口邊緣（領部）在具有光澤線狀凹槽結構內，層層瓦片狀相疊，狀似波浪，向內外兩端下降。袋上半部組織內壁乾燥，有朝下突出的結構；袋下半部組織內壁佈滿由緊密細胞組成的消化腺，壁內組織膨鬆。

Nepenthes alata Blanco is a tropical insectivorous plant with pitchers which can catches and digests insects. This study reported some of the morphological features of pitcher by using stereomicroscope, light microscope, and scanning electron microscopy. This study also showed that the inner surface of the lid was covered with nectar glands, which were evenly distributed in the cortex layer. The nectar glands were compose of palisade parenchyma-like cells, and connected with vascular bundle. The rim of the opening of pitcher was shining, its structures were layered with a wavy shape, and it descended to both ends. The inner surface of the tissue beyond the rim at the top half of pitchers dried with cells and protruded downward. However, the inner surface of the tissue at the bottom of pitchers was covered with digestive glands which were made of condensed cells with loosen inner tissue.