東亞地區水韭屬植物親緣關係研究

Abstract

本研究利用核ribosomal ITS及LEAFY的第二個intron片段，以東亞地區水韭屬植物為對象，加上紐澳與美洲地區其他種類的水韭屬植物，進行親緣關係樹的重建。希望能藉此分子資料，來輔助形態比對的資料，以釐清金門地區水韭族群的分類地位，並由親緣關係樹上的歸群，瞭解東亞地區水韭屬植物間的親緣與雜交關係。 研究結果顯示ITS片段對東亞地區種類間的關係無法提供良好的解析。在LEAFY片段上，金門地區水韭族群雖與I. taiwanensis相近，但有一位點一致地與I. taiwanensis有差異；形態上兩者在球莖瓣數、大孢子大小有穩定差異。因此，本研究建議將金門地區水韭族群處理為I. taiwanensis的變種。 LEAFY片段上的結果支持先前對I. sinensis var. sinensis所提出的推論，I. sinensis var. sinensis應是異源多倍體，I. taiwanensis與I. yunguiensis可能是其雜交親本。此外，本研究發現I. asiatica應與I. japonica在親緣關係上較為接近。

The study focuses on the quillworts in East Asia and combines with the quillworts of Austrulia and America. The nuclear ribosomal ITS and the second intron of LEAFY were used to construct the phylogenetic tree. Depending on the molecular data, we hope that it is helpful to decide whether the quillwort from Kinmen is a new species or not. Besides, we hope to know the relationship of the quillworts from East Asia. The results showed that the data of ITS sequence couldn’t provide useful information to find out the relationship of the quillworts from East Asia. In the data of the second intron of LEAFY, the sequences from Kinmen are similar to the sequences of I. taiwanensis. But there is one site agree different between I. sp（Kinmen）and I. taiwanensis. There are stable differences on morphology between I. sp（Kinmen）and I. taiwanensis：the lobes of corm、the size of megaspores. The results of this study suggest that I. sp（Kinmen）is a variety of I. taiwanensis. Besides, the data of the second intron of LEAFY approves that I. sinensis var. sinensis is a allopolyploid. I. taiwanensis and I. yunguiensis could be the parents of I. sinensis var. sinensis. In this study, we find that I. asiatica might be close to I. japonica.