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1.
珍珠菜属系统发育关系的初步研究   总被引:5,自引:0,他引:5  
本文运用形态学性状对珍珠菜属(Lysimachia)进行系统发育分析。内类群包括珍珠菜属29个代表种以及珍珠菜族其它单种、寡种属;仙客来属(Cylclamen)被选作外类群。最简约性分析表明,珍珠菜属并不构成-自然分类群;在其严格一致化树的二岐分支中,异花珍珠菜(L.crispidens)单独构成一支,其它所有内类群构成一支。香草亚属(subgen.Idiophyton)、木黄连花亚属(subgne.Lysimachiopsis)以及珍珠菜亚属(subgen.palladia)均表现为单系群,而黄连花亚属(subgen.Lysimachia)则为一异形的并系群。球尾花亚属(subgen.Naumburgia)仍“内藏”于珍珠菜属的主体之中。而喉鳞花亚属(subgen.Seleucia)则偏离出来而与七瓣莲属(Trien talis)构成姐妹群。如何准确地界定珍珠菜属和进行属下分类群的划分,还需进一步研究。  相似文献   

2.
通过对广义蓼属及近缘属共32个代表种内转录间隔区ITS序列的分子系统学分析,尝试研究备受争议的广义蓼属及近缘属的物种族、属、组级的划分问题,结果显示,广义蓼属在系统发育树上并不能形成一个单系类群,这些物种共聚为3大支,分别对应春蓼族、蓼族及荞麦族,其中荞麦属与翅果蓼属形成了一支独立于春蓼族及蓼族之外的类群。在春蓼族中,冰岛蓼属与分叉蓼组形成一个单系类群。  相似文献   

3.
采用DNA分子测序技术对梧桐科5个族30个代表种的rbcL基因及核糖体DNA的内转录间隔区ITS序列(包括ITS1、ITS2和5.8srRNA基因)进行了序列分析。使用PAUP4.0b10软件对序列进行统计和分支分析。用启发式搜索方法寻找最简约树。从严格一致性树来看,梧桐科的全部代表类群主要被分为4支,一支仅为Sterculieae所构成;一支包括Helictereae的全部代表种;一支由Byttnerieae代表种所构成;最后一支由Dombeyeae和单属族翅子树族Pterospermeae所构成。rbcL和ITS系统树的不同仅表现在族内个别代表类群的位置和族的分支方式上。分析结果表明,与Helictereae相比,翅子树属,Pterospermum与Dombeyeae有更近的亲缘关系。然而,在外部形态、内部解剖和胚胎学方面,二者之间又存在诸多差异.故支持将Pterospermum另立为Ptcrospermeae的观点。  相似文献   

4.
沼兰族是兰科植物的大族之一,约2000种,除了极地和沙漠地区,全球均有分布.该族植物主要分布在热带地区,尤其在东南亚、热带美洲、非洲以及澳大利亚等地区种类非常丰富.目前,已有关于该族植物形态和分子系统的研究,但有关该族亚族和属间的系统关系尚不清楚,属的界定争议也较大.该文基于核基因片段 ITS 和叶绿体基因片段 mat K 序列,采用最大简约法、最大似然法贝叶斯推理分析法,对现有沼兰族主要属的123种植物和10个外类群植物进行了分子系统学研究.结果表明:沼兰族主要分为3个亚族分支,包括附生的鸢尾兰亚族(Oberoniinae)、地生的羊耳蒜亚族(Liparidinae)和沼兰亚族分支(Crepidium clade).鸢尾兰亚族包括6个属、羊耳蒜亚族分支包括5个属、沼兰亚族分支包括4个属;丫瓣兰亚族(Ypsilorchidinae)应归并为鸢尾兰亚族;Disticholiparis 属与 Stichorkis 属的模式标本相同,应并入 Stichorkis 属;沼兰属(Cre-pidium )和无耳沼兰属(Dienia )的唇瓣结构差异较大,但二者均为单系类群.此外,在收集野外实验材料过程中,发现了2种产自中国西南部和越南北部的沼兰族新种,分别命名为麻栗坡羊耳蒜(Platystyliparis mali-poensis G.D.Tang,X.Y.Zhuang & Z.J.Liu)和秉滔羊耳蒜(Cestichis pingtaoi G.D.Tang,X.Y.Zhuang &Z.J.Liu).  相似文献   

5.
通过对广义蓼属及近缘属共32个代表种内转录间隔区ITS序列的分子系统学分析,尝试研究备受争议的广义蓼属及近缘属的物种族、属、组级的划分问题,结果显示,广义蓼属在系统发育树上并不能形成一个单系类群,这些物种共聚为3大支,分别对应春蓼族、蓼族及荞麦族,其中荞麦属与翅果蓼属形成了一支独立于春蓼族及蓼族之外的类群。在春蓼族中,冰岛蓼属与分叉蓼组形成一个单系类群。  相似文献   

6.
基于细胞核rDNA ITS片段的水青冈属的分子系统发育   总被引:6,自引:0,他引:6  
对山毛榉科水青冈属6种、1亚种、1栽培变种的ITS区片段进行了测序和分析,并对其中2个具有ITS序列多态性的分类群进行了ITS区克隆。水青冈属ITS系统发育树聚成两支,位于基部的是分布于北美的大叶水青冈,另一分支则包括了欧洲和东亚的类群。在欧洲和东亚分支中,又包括两支,其中日本北部的波叶水青冈位于基部,台湾水青冈和欧亚大陆的水青冈形成另外一支。ITS区分析与现行的水青冈属基于形态学性状的属下分类系统有一定差异,而与本属现存物种的地理分布格局较为一致。各类群间TIS区序列差异较小,显示属内现存物种的分化时间不是太长。  相似文献   

7.
测定了簇毛黄耆亚属(Pogonophace)4组8种和外类群Caragana roborovskyi的ITS序列,从GenBank中调出相关12属47种的ITS序列,组成数据距阵,应用PAUP程序中的最大简约法构建了系统发育树状图.扁荚组(Sect. Sesbanella)与亚属其余类群在系统树上处于不同的分支,亲缘关系较远,这个亚属不是一个单系类群;膨果组(Sect. Bibracteola),背扁组(Sect. Phyllolobium)和袋果组(Sect. Trichostylus)作为一个单系类群能得到ITS序列的支持,但与鱼鳔槐亚族比与黄耆属其他类群的关系更近; Astragatus complanatus和A. tribulifolius可能为一对替代种;亚属下的分组以及膨果组下系的划分都得不到ITS序列分析的支持.  相似文献   

8.
四照花亚属(Cornus subg.Syncarpea)隶属于山茱萸科山茱萸属(Cornus),我国该亚属共有5种8亚种。为探讨四照花亚属nrDNA ITS序列的致同进化不完全现象及假基因产生的可能原因,分析了该亚属4种(每种1~2个居群)共21个个体的nrDNA ITS序列。结果表明,这些类群的nrDNA ITS存在多态性,通过分析这些nrDNA ITS克隆序列的G+C含量、5.8S保守基序和二级结构最小自由能,推测其可能存在假基因。系统发育研究结果显示所有nrDNA ITS序列分成5个分支,同一个体的不同拷贝被分别置于两个甚至多个分支中,且不同分支显示了不同种间关系。四照花亚属物种个体内部存在nrDNA ITS不完全致同进化,可能归咎于不完全的世系分选(incomplete lineage sorting)、种间杂交或多倍化等进化事件,从而导致基因组内nrITS区序列出现多态性,同时也导致难以通过外部形态来划分亚属内种间界限。  相似文献   

9.
rDNA片段的序列分析在苦苣苔亚科系统学研究中的应用   总被引:18,自引:1,他引:18  
本文测定了苦苣苔亚科4族、5属、5种植物的核糖体DNA中的内转录间隔区(ITS)序列及5.8s rRNA基因的3′端序列。这几种苦苣苔亚科植物的ITS-1的长度范围为234~258 bp,ITS-2的长度范 围为218~246bp。Whytockia bijieensis的ITS-1(258bP)和ITS-2(218 bp)在长度、序列及GC含量上 均与其它几个种有较大差异,其代表的尖舌苣苔族可能很早就自苦苣苔亚科的祖先沿单独的一个分支 演化。以w.bijieensis作为功能性外类群,运用PAUP软件分析仅得到一个最简约树。在简约树上, Cyrtandra umbelliferm、Briggsia longipes和Anna mollifolia形成一个单系群,bootstrap分析对该分支的 支持强度达97%,Chirita crasslfolia位于该分支的基部。由于系统树上Cyrtandra umbellifera代表的 浆果苣苔族和Anna mollifolid代表的芒毛苣苔族均起源于长蒴苣苔族,结合这3个族在形态上存在过渡系列,建议将浆果苣苔族和芒毛苣苔族均并入长蒴苣苔族。  相似文献   

10.
rDNA片段的序列分析在苦苣苔亚科系统学研究中的应用   总被引:8,自引:1,他引:7  
本文测定了苦苣苔亚科4族、5属、5种植物的核糖体DNA中的内转录间隔区(ITS)序列及5.8s rRNA基因的3′端序列。这几种苦苣苔亚科植物的ITS-1的长度范围为234~258 bp,ITS-2的长度范 围为218~246bp。Whytockia bijieensis的ITS-1(258bP)和ITS-2(218 bp)在长度、序列及GC含量上 均与其它几个种有较大差异,其代表的尖舌苣苔族可能很早就自苦苣苔亚科的祖先沿单独的一个分支 演化。以w.bijieensis作为功能性外类群,运用PAUP软件分析仅得到一个最简约树。在简约树上, Cyrtandra umbelliferm、Briggsia longipes和Anna mollifolia形成一个单系群,bootstrap分析对该分支的 支持强度达97%,Chirita crasslfolia位于该分支的基部。由于系统树上Cyrtandra umbellifera代表的 浆果苣苔族和Anna mollifolid代表的芒毛苣苔族均起源于长蒴苣苔族,结合这3个族在形态上存在过渡系列,建议将浆果苣苔族和芒毛苣苔族均并入长蒴苣苔族。  相似文献   

11.
The phylogeny of the tribe Menispermeae (Menispermaceae) represented by 20 species of 9 genera in China, was reconstructed based on sequence analysis of the internal transcribed spacers (ITS) (including ITS1, ITS2, and 5.8S rRNA gene ) of nuclear ribosomal DNA. Three species of two genera in the tribe Tinosporeae were designated as outgroups. Direct PCR sequencing method was used in the study, The sizes of ITS within trib. Menispermeae range from 527 to 601 bp. The aligned length is 667 bp, which provides 281 phylogenetically informative sites when gaps are treated as missing. The results of phylogenetic analyses show that: ① trib. Menispermeae is a monophyletic group strongly supported by a bootstrap value of 100%; ② Pachygone valida, whose systematic position was uncertain in the previous classification, should be placed in the Cocculus. ③Sinomenium and Menispermum are two close genera of the tribe. Their sequcences are very similar to each other, with ITS1 having 41 to 73 bp longer than that of the other genera in trib. Menispermeae. ④ Stephania and Cyclea are also closely related. The former forms two major clades, which are approximately consistent with the two traditional subgenera: subgen. Stephania and subgen. Tuberiphania. The species of Cyclea are mutually little diverged in complete ITS sequences, and they com-prise a sister clade to the genus Stephania.  相似文献   

12.
The Menispermaceae family contains ca. 72 genera with 450 species that are almost entirely tropical. Its phylogeny at the tribal level has never been examined using molecular data. Here we used DNA sequences of the chloroplast matK gene and trnL-F regions, and the nuclear ITS region to study the delimitation and position of the tribe Menispermeae within the family and its subtribal monophyletic groups. Family-wide phylogenetic analyses of the chloroplast data produced two strongly supported clades. The first clade contains two subclades: Coscinieae including Arcangelisia and Anamirta, and Tinosporeae sensu lato including Fibraureae, supported by morphological characters, such as traits of the cotyledon, stylar scar and embryo. The second clade consists of the tribes Menispermeae sensu DC. and Tiliacoreae Miers. All our analyses surprisingly recognized that tribe Menispermeae is not monophyletic unless tribe Tiliacoreae is included, suggesting that characters of cotyledon and stylar scar are very important for the infrafamilial classification, and that endosperm presence vs. absence was over-emphasized in traditionally tribal division of the family. Our topologies indicate a secondary loss of endosperm. The monophyly of two subtribes of the tribe Menispermeae, Stephaniinae and Cissampelinae, is supported by the cpDNA and ITS data, as well as by morphological characters, including aperture types and shapes, and colpal membrane features of pollen grains, and sepal number of male flowers. The Cocculinae was recognized as a paraphyletic group containing the remaining genera of the tribe Menispermeae.  相似文献   

13.
The epidermal characters of mature leaves of 29 genera, 50 species and 3 varieties (totally 56 samples) representing all the 5 tribes in the family Menispermaceae were examined under the light microscope. The main conclusions are as follows: (1) The shape of the epidermal cells is polygonal or irregular, and the anticlinal walls are straight or waved in the family. In some genera a special arrangement of epidermal cells is named as “rosette-cell arrangement" for the first time. The lower epidermal cells were found to have a papilla in Stephania, Diploclisia and Legnephora . (2) In some genera, the anticlinal walls are oblique, rather than perpendicular, to the surface. (3) The stomatal apparatuses, generally restricted to the lower surface of the leaves, were assigned to anomocytic, staurocytic, cyclocytic, anisocytic and actinocytic types, and their distribution on the epidermis may be of diffuse pattern or island congregating pattern. (4) The cells of both upper and lower epidermis in the tribe Pachygoneae and Fibraureae are generally polygonal with straight or arched anticlinal walls, and the stomatal apparatuses are usually staurocytic and actinocytic. The cyclocytic stomatal apparatus was found only in two genera of the tribe Pachygoneae. By contrast, the epidermal cells of the tribes Anomospermeae, Tinosporeae and Menispermeae are generally irregular with waved anticlinal walls, and the stomatal apparatuses are predominantly anomocytic. These correlated characters are of much significance in delimiting tribes within the Menispermaceae, and also provide evidence for studies on systematic relationships of several genera.  相似文献   

14.
Vitaceae (the grape family) consist of 16 genera and ca. 950 species primarily distributed in tropical regions. The family is well‐known for the economic importance of grapes, and is also ecologically significant with many species as dominant climbers in tropical and temperate forests. Recent phylogenetic and phylogenomic analyses of sequence data from all three genomes have supported five major clades within Vitaceae: (i) the clade of Ampelopsis, Nekemias, Rhoicissus, and Clematicissus; (ii) the Cissus clade; (iii) the clade of Cayratia, Causonis, Cyphostemma, Pseudocayratia, Tetrastigma, and an undescribed genus “Afrocayratia”; (iv) the clade of Parthenocissus and Yua; and (v) the grape genus Vitis and its close tropical relatives Ampelocissus, Pterisanthes and Nothocissus, with Nothocissus and Pterisanthes nested within Ampelocissus. Based on the phylogenetic and morphological (mostly inflorescence, floral and seed characters) evidence, the new classification places the 950 species and 16 genera into five tribes: (i) tribe Ampelopsideae J.Wen & Z.L.Nie, trib. nov. (47 species in four genera; Ampelopsis, Nekemias, Rhoicissus and Clematicissus); (ii) tribe Cisseae Rchb. (300 species in one genus; Cissus); (iii) tribe Cayratieae J.Wen & L.M.Lu, trib. nov. (370 species in seven genera; Cayratia, Causonis, “Afrocayratia”, Pseudocayratia, Acareosperma, Cyphostemma and Tetrastigma); (iv) tribe Parthenocisseae J.Wen & Z.D.Chen, trib. nov. (ca. 16 spp. in two genera; Parthenocissus and Yua); and (v) tribe Viteae Dumort. (ca. 190 species in two genera; Ampelocissus and Vitis).  相似文献   

15.
16.
The internal transcribed spacer (1TS) region (1TS1, ITS2 and 5.8S rDNA) of the nuclear ribosomal DNA (nrDNA) was amplified via PCR in 28 taxa of Abies Mill. The amplified fragments showed length polymorphism among species, with species from Central America and two species from North America having a length of approximately 2 500 base pairs (bp) and the remaining taxa having a length of approximately 1 700 bp based on 100 bp and 1 kb ladder standard markers. The complete sequencing of ITS of Abies bracteata showed that the shorter type is 1 697 bp (1TS1 is 1 296 bp, 5.8S + 1TS2 is 401 bp). For the longer one, the partial rrs1 and complete 5.8S + ITS2 sequencing revealed that thelength of 5.8S + ITS2 is the same as that of the shorter type. The length difference of ITS in Abies is mainly due to the length difference in the ITS1 region, a result similar to the previous findings in other genera of Pinaceae. Variation in ITS length seems well correlated with morphological and geographic characters in Abies, suggesting that the length variation may be a phylogenetically informative character within the genus, long ITS was also found in other genera of Pinaceae in the previous studies. The long length of ITS in the family makes the sequencing of the region and subsequent alignment of sequences among species or genera more difficult than in taxa with short ITS, such as angiosperms. Although the length variation of ITS in the genus Abies is significant, the homogenous of ITS sequence between the longer one and the shorter one is obvious if the insertion in the longer ITS is ignored.  相似文献   

17.
A molecular phylogeny of the subfamily Cyrtandroideae represented by five genera of four tribes was constructed using sequence analysis of the internal transcribed spacers (ITS) and partial 5.8 S rRNA gene (3’end) of nuclear ribosomal DNA. Direct PCR sequencing method was used in the study. The sequences of ITS-1 in the five species range from 234 bp to 258 bp in size and those of ITS-2 from 218 bp to 246 bp. The ITS-1 (258 bp) and ITS-2 (218 bp) of Whytockia bijieensis differ greatly from those of the other species in size, sequence and G + C content, and therefore the tribe Klugieae represented by W. bijieensis may have diverged from the ancestor of the subfamily Cyrtandroideae at a very early time. In PAUP analysis, W. bijieensis was used as the functional outgroup, and only one most parsimonious Fitch tree was obtained through exhaustive search. The tree has 353 steps, with CI = 0. 932 and RI = 0. 529. In the tree, Chirita crassifolia is basal to a monophyletic group comprising Cyrtandra umbellifera, Briggisia longipes and Anna mollifolia, and the monophyletic group is strongly supported by the bootstrap value (97). The tribes Trichosporeae and Cyrtandreae represented respectively by Anna mollifolia and Cyrtandra urnbellifera both evolved from the tribe Didymorcarpeae, which can explain why many intermediate taxa exist among the three tribes. According to this, the present authors suggest that the tribe Trichosporeae and the tribe Cyrtandreae be merged with the tribeDidymocarpeae.  相似文献   

18.
Chloroplast trnL/F and nuclear ribosomal ITS and ETS sequence data were used to analyze phylogenetic relationships among members of tribe Mimuleae (Scrophulariaceae) and other closely related families in Lamiales. The results of these analyses led to the following conclusions. (1) The Australian genera Glossostigma and Peplidium and the taxonomically isolated Phryma join four genera of tribe Mimuleae to form a well-supported clade that is distinct from other families in the Lamiales. We refer to that clade as the subfamily Phrymoideae. (2) The genera Mazus and Lancea (tribe Mimuleae) together form a well-supported clade that we recognize as the subfamily Mazoideae. Mazoideae is weakly supported as sister to Phrymoideae. We assign Mazoideae and Phrymoideae to a redefined family Phrymaceae. (3) Mimulus is not monophyletic, because members of at least six other genera have been derived from within it. In light of the molecular evidence, it is clear that species of Phrymaceae (about 190 species) have undergone two geographically distinct radiations; one in western North America (about 130 species) and another in Australia (about 30 species). Phylogenetic interpretations of morphological evolution and biogeographical patterns are discussed.  相似文献   

19.
The relationships among the species of Balsamorhiza and Wyethia (Asteraceae: Heliantheae) were examined using data from the internal transcribed spacer (ITS) region of the nuclear ribosomal DNA. The ITS sequences were obtained from nine species of Balsamorhiza and 14 species of Wyethia as well as seven outgroup genera. Five of the outgroup genera were members of the subtribe Engelmanniinae of the tribe Heliantheae, the subtribe that includes Balsamorhiza and Wyethia. The resulting trees show that Balsamorhiza and Wyethia together form a monophyletic group. Balsamorhiza alone is monophyletic, but neither of its two sections is monophyletic. Wyethia is paraphyletic. One group of Wyethia species, including all members of sections Alarconia and Wyethia as well as W. bolanderi from section Agnorhiza, is monophyletic and sister to Balsamorhiza. The other species of Wyethia (all placed in section Agnorhiza) are part of a polytomy along with the clade composed of Balsamorhiza plus the rest of Wyethia.  相似文献   

20.
对球壳孢目真菌首次采用PCR-RFLP和RAPD进行了系统发育研究。以ITS1和ITS4为引物对4属12种24个菌株的核糖体DNA转录间区(ITS)进行了PCR扩增,4种内切酶(AluI,Hha,MspI,TaqI)酶切,结果表明:主要属的ITS区长度不同,同属不同种相同。Coniothyrium,Phylosticta,Ascochyta,SeptoriaITS区长度分别为630,560,550,540bp;酶切图谱属间差别明显,属内种间基本一致,暗示传统的分种可能过细,某些种的成立还有商榷的余地,PCR-RFLP对确定疑难种属的地位有重要的意义。3属8种16个菌株的RAPD结果表明,种内图谱相同或图谱类型相同,而种间明显不同,揭示出过去所划分的种的确存在本质的差别,但是否达到种级的差别还有待于进一步研究  相似文献   

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