台灣菊科植物的系統分類與染色體數之研究

Abstract

菊科植物種類繁多，為顯花植物最大科之一，根據Willis（1966）的統計，全世界約有900屬、13,000種有關台灣產的菊科植物，過往雖有不少新種或新記錄種類的報告，但多散見於各植物學期刊上，且常僅有名錄而乏系統性的研究。有鑒於系統分類以及細胞學上的知見年來頗多增益，同時新添之歸化植物種類亦復不少，對於是科植物重加整理，做一系統研究實為當務之急。 本篇旨在綜合有關本省產菊科植物之細胞學和分類上的新知。據筆者研究的結果，台灣共有自生及歸化菊科植物2亞科、11族、74屬、118種及42種下分類群，其中Hypochoeris係本次研究上之新記錄屬。Blumea manillensis, Emilia sagittata, Petasites japonicus, Hypochoeris radicata, Taraxacum officinale則係本次研究首次記錄之種類，後二者為新歸化植物。 本篇除做形態之觀察與分類的研究外，並對省產菊科植物11族、74屬、76種之體染色體數加以研討，其中1屬20種以及4種下分類群係首次之報告，15種染色體數異於前人之報告；就中並發現染色體之異數性（Aneuploidy）和多倍體性（polyploidy）在艾納香屬（Blumea）的種化過程擔任重要角色。

Compositae is one of the largest families of flowering plants, comprising about 900 genera, with over 13,000 species (Willis, 1966). Many papers have previously been published listing new or known species of Taiwan Compositae. However, they are either widely scattered in various botanical literatures, or only enumerations; moreover, many are out-of-date. Much new systematic and cytological knowledge has been accumulated during the past few decades, and two naturalized species (Hypochoeris radicata and Taraxacum officinale) are here recorded for the first time. In the present study, an attempt has been made to summarize our present taxonomical and cytological knowledge of all Taiwan species of the Aster family. A total of 74 genera, 178 species and 42 infraspecific taxa belonging to 2 subfamilies and 11 tribes are recognized. One genus, Hypochoeris, and 3 species (Blumea manillensis, Emilia sagittata, Petasites japonicus) are recorded here for the first time. In addition to morphological observations and systematic studies, somatic chromosome counts for 76 taxa belonging to 47 genera are reported. First counts are reported for 1 genus, 20 species and 4 infraspecific taxa; additional counts for previously counted taxa are made for 52 taxa, of which 15 are new numbers. And it is found that polyploidy and aneuploidy have played an impurtant role in the speciation among Blumea species.