本文關(guān)鍵詞：石松科的分子系統(tǒng)學(xué)研究　出處：《重慶師范大學(xué)》2017年碩士論文　論文類型：學(xué)位論文

  更多相關(guān)文章： 石松科 單系群 分子系統(tǒng)

【摘要】：石松科(Lycopodiaceae)約388種,全球廣布,主產(chǎn)熱帶地區(qū)。圍繞石松科已開展了細(xì)胞學(xué)、形態(tài)學(xué)、解剖學(xué)、分子系統(tǒng)學(xué)等方面的研究,提高了對(duì)石松科多樣性和進(jìn)化的理解,但主要問題仍然存在:(1)形態(tài)特征簡單,根據(jù)形態(tài)進(jìn)行分類非常困難;(2)取樣不夠和使用的基因片段較少,屬間關(guān)系沒有被很好的確立和已被承認(rèn)的大部分屬的單系沒有被很好檢測。因此,迫切需要大范圍取樣和增加基因片段對(duì)石松科進(jìn)行分子系統(tǒng)學(xué)研究。本研究對(duì)石松科取樣323個(gè)約130種,運(yùn)用5個(gè)葉綠體片段(rbcL,atpA,trnL-F,psbA-trnH,rps4-trnS),綜合最大似然法和最大簡約法重建了石松科的分子系統(tǒng)關(guān)系。研究結(jié)果顯示:(1)石松科可分為三個(gè)大支,支持將石松科分為三個(gè)亞科,即石杉亞科(Huperzioideae)、石松亞科(Lycopodioidieae)和小石松亞科(Lycopodielloideae);(2)石松亞科和小石松亞科的親緣關(guān)系較近,而與石杉亞科的親緣關(guān)系較遠(yuǎn);(3)三個(gè)大支可進(jìn)一步分為17個(gè)支,其中16個(gè)支分別代表16個(gè)屬,與PPG I的分類處理一致,而Lycopodium serpentinum形成了獨(dú)立的支。在這16個(gè)屬中,除石杉屬(Huperzia)外,其余15個(gè)屬的單系均得到了很好的支持(ML BS≥96,MP JK≥86),石杉屬的單系勉強(qiáng)得到支持(ML BS=50,MP JK=55)。研究顯示Phylloglossum形成的長枝吸引降低了石杉屬單系的支持率,在排除Phylloglossum后,石杉屬的單系得到了較高支持(ML BS=80,MP JK=92)。盡管Phylloglossum和石杉屬為姊妹群關(guān)系,但兩者形態(tài)差異較大,遺傳距離遠(yuǎn),故本研究接受石杉屬和Phylloglossum均作為獨(dú)立的屬。因此,本研究結(jié)果支持PPG I對(duì)石松科的分類處理,將石松科分為三個(gè)亞科16個(gè)屬,即石杉亞科,包括石杉屬(Huperzia),馬尾杉屬(Phlegmariurus),Phylloglossum;小石松亞科,包括Lateristachys,小石松屬(Lycopodiella),垂穗石松屬(Palhinhaea),擬小石松屬(Pseudolycopodiella);石松亞科,包括Austrolycopodium,Dendrolycopodium,扁枝石松屬(Diphasiastrum),Diphasium,藤石松屬(Lycopodiastrum),石松屬(Lycopodium),Pseudodiphasium,Pseudolycopodium,Spinulum。對(duì)于Lycopodium serpentinum,Kunze于1846年發(fā)表,這個(gè)種均不與擬小石松屬和小石松屬形成單系群,而是獨(dú)立形成一支并與垂穗石松屬構(gòu)成姊妹群關(guān)系,由于本研究數(shù)據(jù)僅包括了來自GenBank一個(gè)序列rbcL,所以不作處理,其系統(tǒng)位置需要進(jìn)一步研究。
[Abstract]:There are 388 species of Lycopodiaceae, which are widely distributed all over the world and are mainly produced in tropical regions. Cytology, morphology, anatomy, molecular systematics and so on have been studied around the family Lycopodiaceae. The understanding of the diversity and evolution of Pinaceae is improved, but the main problem is that the morphological characteristics are simple, and it is very difficult to classify them according to their morphology. (2) inadequate sampling and use of fewer gene fragments, poorly established intergeneric relationships and poorly tested monophyls of most of the recognized genera. There is an urgent need for extensive sampling and increasing gene fragments to study the molecular phylogeny of Pinaceae. In this study, 323 species of Pinaceae were sampled and 5 chloroplast fragments were used to study the molecular phylogeny of Pinaceae. TrnL-FU psbA-trnHN rps4-trnS. The molecular phylogenetic relationship of Pinaceae was reconstructed by using the maximum likelihood method and the maximum minimization method. The results show that the family of Pinaceae can be divided into three large branches, which supports the division of Pinaceae into three subfamilies. They are Huperzioideaeae, Lycopodioidieaeae and Lycopodielloideaeae; (2) the relationship between the subfamily of Pinaceae and the subfamily of Pinaceae is close, but the relationship with the subfamily of Taxodiaceae is far away. (3) three large branches can be further divided into 17 branches, of which 16 branches represent 16 genera respectively, which is consistent with the classification of PPG I. Lycopodium serpentinum forms a separate branch, except for Huperzia, which belongs to 16 genera. The other 15 monophyls were all well supported by MLBS 鈮，

本文編號(hào)：1409657