利用掃瞄式電子顯微鏡（SEM）技術觀察台灣產10種碗蕨科孢子形態

A Morphological Study on Spores of 10 Species of Dennstaedtiaceae from Taiwan with Scanning Electron Microscopy Technique

本研究乃利用掃描式電子顯微鏡（SEM）觀察採自台灣各地碗蕨科5屬10種孢子的細微構造，經觀察結果綜合比較發現，孢子細微構造的特徵，可作為碗蕨科5個屬間及所包括的10個物種間鑑定上輔助的依據。姬蕨屬及栗蕨屬等2屬的孢子為單裂縫型，其中栗蕨屬的孢子不具周壁，姬蕨屬的孢子具周壁且呈刺狀紋飾而可與前一屬區分。稀子蕨屬、碗蕨屬及鱗蓋蕨屬等3屬的孢子為三裂縫型，其中稀子蕨屬的孢子外壁不具明顯紋飾可與外壁具紋飾的碗蕨屬及鱗蓋蕨屬區分；而碗蕨屬孢子外壁呈明顯的細網狀紋飾可與孢子外壁呈不同程度加厚或呈顆粒狀紋飾的鱗蓋蕨屬區分。孢子微細構造除了作為碗蕨科屬間的分類依據外並可進一步作為種間的分類特徵，姬蕨屬中姬蕨的孢子具裂縫且一端呈兩分叉狀，細葉姬蕨的孢子不具明顯裂縫而可區分開。碗蕨屬中碗蕨的孢子外壁表面形成不同程度加厚的帶狀紋飾，與具顆粒狀紋飾的細毛碗蕨的孢子可容易的區別。鱗蓋蕨屬中的虎克氏、熱帶、粗毛及亞粗毛鱗蓋蕨，則可藉由孢子周壁的增厚情形及紋飾的不同而加以區別。 Spores of 10 species in five genera of the family Dennstaedtiaceae were examined, using thescanning electronic microscopy (SEM) technique. The fine structure of the spores was found to be auseful diagnostic character for the generic and specific distinction for Dennstaedtiaceae. Spores of thegenera Hypolepis and Histiopteris are monolete and the two genera are distinguishable by difference intheir perispore grains types, while those of the genera Monachosorum, Dennstaedtia, and Microlepia aretrilete, and the three genera are distinguishable by their exine grain types. For distinction of congenericspecies, fissure margos of spores is a useful character for distinguishing two species of Hypolepis: H.punctata (Thunb.) Mett. and H. tenuifolia (Forst.) Bernh., the exine grains for two species ofDennstaedtia: D. scabra (Wall.) Moore and D. hirsuta (Sw.) Mett. ex Miq., and thickness and grains forfour species of Microlepia: M. hookeriana (Wall.) Presl, M. speluncae (L.) Moore, M. strigosa (Thunb.)Presl, and M. substrigosa Tagawa.