Evolution of Apocarpy in Alismatidae Using Phylogenetic Evidence from Chloroplast rbcL Gene Sequence Data

基於葉綠體rbcL基因序列對澤瀉亞綱(Alismatidae)離生心皮的起源與演化的研究

陳進明(Jin-Ming Chen) ； 陳丹(Dan Chen) ； Wahiti Robert Gituru ； 王青鋒(Qing-Feng Wang) ； 郭友好(You-Hao Guo)

《Botanical Bulletin of Academia Sinica》 45卷1期 (2004/01) Pp. 33-40

https://doi.org/10.7016/BBAS.200401.0033

摘要

單子葉植物離生心皮類主要集中在澤瀉亞綱。本文基於rbcL基因序列資料構建了澤瀉亞綱的系統發育關係，依據此系統發育關係為框架，討論了澤瀉亞綱不同心皮的起源與演化，尤其是離生心皮的起源與演化。本研究包括了澤瀉亞綱約27屬離生心皮植物中的20屬。研究結果表明離生心皮在澤瀉亞綱中是多次獨立起源的，據初步估計在澤瀉亞綱中離生心皮可能有2次獨立的起源。本文同時估計在澤瀉亞綱中單心皮至少有3次獨立的起源而基部合生心皮則是澤瀉亞綱最原始的心皮性狀。本研究揭示了澤瀉亞綱中不同心皮之間可能的演化過程，即從基部合生心皮向合生心皮或離生心皮方向演化，而單心皮，則很有可能是通過具多數、合生的心皮直接簡化而來；同時它也有可能從具多數、離生的心皮簡化而來。

關鍵字

澤瀉亞綱 ； 離生心皮 ； 基部合生心皮 ； 基因 ； 單心皮 ； 合生心皮

並列摘要

The apocarpous groups in the monocotyledons are mainly concentrated in the subclass Alismatidae. The molecular phylogeny of Alismatidae based on analysis of chloroplast rbcL gene sequence data serves as a framework with which to evaluate character evolution with respect to the derivation of apocarpy in the group. 20 of the 27 genera in the subclass that display apocarpy have been included in our study. Our analysis indicates that apocarpy is polyphyletic within the subclass Alismatidae. Two independent origins of apocarpy in Alismatidae are explored in this study. Three separate origins of a single carpel and two separate origins of syncarpy in the subclass are also proposed. Basally connate carpel condition was the ancestral character in Alismatidae and evolved in two directions. It is possible for the unicarpellate condition to have been directly derived by reduction from syncarpy, and it could also be that the unicarpellate state has been derived from apocarpy by reduction in carpel number. The present results indicate that a progression has occurred in the evolution of carpels in Alismatidae from basally connate carpels through syncarpy or apocarpy to a single carpel.

並列關鍵字

Alismatidae ； Apocarpy ； Basally connate carpels ； RbcL gene ； Single carpel ； Syncarpy ； Unicarpellate