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1.
基于33个广义的形态学性状,对广义飞蛾藤属Porana s.l.进行了分支系统学分析。经过简约性分析,得到了10个同等简约的分支树。10个同等简约树的严格一致化树表明,广义飞蛾藤属是一较为自然的分类群。与广义飞蛾藤属的孢粉学、种皮微形态学研究结果一致,分支分析的结果不支持将广义飞蛾藤属拆分为4个或5个独立的属,应在属内划分分类等级。在整个形态分支树中广义飞蛾藤属4个亚属呈并列2个分支,其中飞蛾藤亚属(subg.Porana)和白花叶亚属(subg.Poranopsis)形成姐妹群构成一分支,三翅藤亚属(subg.Tridynamia)和棒状亚属(subg.Dinetus)以姐妹群的关系构成另一支。鉴于分支分析的Bootstrap支持率不高,广义飞蛾藤属范畴的最后界定和属内等级的划分仍有待于进一步研究。  相似文献   

2.
基于广义形态学性状对木通科的分支系统学分析   总被引:3,自引:1,他引:2  
基于43个广义的形态学性状,对木通科进行了分支系统学分析。经过简约性分析,得到了68个同等简约的分支树。50%多数规则一致树的分支结构与以前建立的族划分系统基本一致。外类群大血藤属与木通科的勃奎拉藤属形成姐妹群,与以前的分支分析结果一致,但在分子系统发育树中,大血藤属却是整个木通科的姐妹群;除此之外,形态分支树的结构与分子树的结构差别不大,但一致性指数、保持性指数和各分支内部支持率均较低。单型的猫儿屎族和串果藤族位于分支树的基部,拉氏藤族与木通族是姐妹群,在木通族内,长萼木通属和木通属是姐妹群,作为一个分支;另一分支是PHS(牛藤果属、八月瓜属和野木瓜属)复合群,牛藤果属位于八月瓜属和野木瓜属各类群的基部。但八月瓜属和野木瓜属的属内系统发育关系仍有待进一步研究。  相似文献   

3.
中国紫金牛属的分支分类学研究   总被引:2,自引:0,他引:2  
基于60个形态学性状,对中国广义报春花科(Primulaceae s.l.)紫金牛属(Ardisia)90个分类群的系统发育关系运用分支分析方法进行了分析。采用最简约性分析得到了100个同等简约树。50%多数规则一致树的分支结构与以前建立的紫金牛亚属划分系统基本一致。外类群酸藤子属、铁仔属、密花树属聚在分支树的最基部,紫金牛属为一单系类群。形态分支树的一致性指数和保持性指数和各分支内部支持率均较低,只在种与变种或亚种之间获得较高的支持率。高木亚属、腋序亚属、短序亚属、顶序亚属处于分支树较为基部的位置,推测这四个亚属的类群在紫金牛属中较为原始;圆齿亚属和锯齿亚属共同组成一大支,二者亲缘关系紧密,推测这两个亚属为该属中最为进化的类群。结合形态学对属内系统发育关系进行了讨论和推测了一些性状的演化趋势,以期为分类修订提供依据。  相似文献   

4.
基于ITS序列分析探讨杜鹃属映山红亚属的组间关系   总被引:15,自引:0,他引:15  
以叶状苞亚属的叶状苞杜鹃为外类群,以杜鹃属映山红亚属(subg.Tsutsusi)2组12种杜鹃和羊踯躅亚属(subg.Pentanthera)3种4种杜鹃的ITS区(包括5.8S rDNA)的序列了系统学分析。3个亚属的ITS区序长度范围为642-645bp。排序后ITS区的序列长度为653个位点,gap做缺失处理时,变异位点和信息位点分别占6.58%和3.68%。运用PAUP4.0软件分析,获得15个最简树,步长为75,一致性指数(CI)和维持性指数(RI)值分别为0.9333和0.9515,利用15个最简约树获取严格一致树,结果表明:1)映山红亚属为一单系类群,其内部支持率为81%;2)不支持将R.ashiroi独立成假映山红组,也不支持将R.tashiroi并入映山红组,而支持将R.tashiroi并入轮生叶组中的观点;3)支持将R.tsusiophyllum并入映山红组中的观点;4)大字杜鹃的系统位置还需进一步的研究。  相似文献   

5.
以礼草属系统发育的分析   总被引:7,自引:2,他引:5  
基于分支系统学的原理和方法。对禾本科以礼草属进行了系统发育分析,以礼草属是个单系在群,它的32个外部性状选作极性分析。鹅观草属中的肃草作为外类群,采用PAUP程序对矩阵进行运算,获得了1个最简约的谱系分支图。在分支图上,以民礼草属26个种可以归为3个组,但不适合于划分系,3个组中各组包含的种数分别与传统分类的3个组基本吻合,从而支持了传统分类的结果。同时,分支图还展示了各个类群间的亲缘演化关系,其  相似文献   

6.
中鲤亚属的分支系统学分析   总被引:2,自引:0,他引:2  
基于外部形态特征和内部骨骼特征对鲤科鲤属中鲤亚属进行了分支系统学分析,内群包括中鲤亚属的全部5种和鲤亚属的2种鱼类,外群采用乌原鲤。在鲤属鱼类和外群间共有48个性状存在变化。系统发育分析采用PAUP^*软件的Parsimony和Bootstrap两种方式的Branch-and-Bound算法,排除不能极化的特征和特有离征之后,还有28个特征可用,由这28个特征可得到唯一的系统树,树长69,一致性系数0.7246,排除无用特征的一致性系数0.6122,保留系数0.6346。由5种中鲤组成的中鲤亚属明显不构成一个单系群。结果表明:中鲤亚属是一个复系群,该类元应该被撤销。  相似文献   

7.
菝葜科基于形态学证据的系统发育分析   总被引:1,自引:0,他引:1  
对全世界范围分布的菝葜科Smilacaceae的79个代表种(包括了全部的属和组), 以分布于南美洲的Philesia Comm. ex Juss.和Lapageria Ruiz &; Pav.属为外类群, 选取包括花粉和染色体性状在内的47个广义的形态学性状进行了分支分类系统发育分析, 同时以表征分类的方法构建了距离树(NJ)辅助分析, 首次对世界分布的菝葜科各属间及属内的系统发育关系作了探讨。(1)Ripogonum与菝葜属Smilax +肖菝葜属Heterosmilax互为姐妹群, 但是距离较远, 支持将类菝葜属(新拟中文名)Ripogonum独立为科的观点; (2)肖菝葜属在菝葜科内处于较为进化的分支上, 并与菝葜属土茯苓组sect. Coilanthus的部分种组成一个具较高支持率(88%)的单系分支, 分析表明肖菝葜属并非是一个好属, 应归入菝葜属; (3)菝葜属6个组的划分大都没有得到支持, 只有东亚北美间断分布的草本菝葜组sect. Nemexia的单系得到很好的支持(93%); (4)分布于南美洲巴西的种类聚为一个单系类群, 表明它们可能有共同的起源, 但由于取样局限, 南美洲种类的系统地位有待进一步研究。  相似文献   

8.
首次报道了15种杜鹃属(Rhododendron)植物、1种杜香属(Ledum)植物和Cassiope fastigiata的内转录间隔区(ITS) (包括5.8S)序列.加上从GenBank下载的13种杜鹃属植物和Bajiaria racemosa的ITS序列,以C. fastigiata和B. racemosa为外类群,用最大简约法对杜鹃属的亚属和组间的系统关系进行了分析.结果表明: 1)杜鹃属是一个单系类群,叶状苞亚属为杜鹃属的基部类群; 2)杜香属确应归并到杜鹃属中,且与有鳞杜鹃亚属有较近的亲缘关系; 3)有鳞杜鹃亚属和杜香构成一个单系分支,该分支是其余无鳞杜鹃花的姐妹群; 4)由无鳞杜鹃花组成的一个分支的内部支持率较低,其中常绿杜鹃亚属和映山红亚属均为内部支持率很高的单系类群,而羊踯躅亚属和马银花亚属均为多系类群; 5)在马银花亚属中,长蕊杜鹃组和马银花组均分别得到强烈支持,马银花组与异蕊杜鹃亚属可能构成姐妹群关系,异蕊杜鹃亚属和马银花组组成的一个分支可能与映山红亚属构成姐妹群关系.  相似文献   

9.
基于ITS序列探讨杜鹃属的亚属和组间系统关系   总被引:10,自引:0,他引:10  
首次报道了 15种杜鹃属 (Rhododendron)植物、1种杜香属 (Ledum)植物和Cassiopefastigiata的内转录间隔区(ITS) (包括 5 .8S)序列。加上从GenBank下载的 13种杜鹃属植物和Bajiariaracemosa的ITS序列 ,以C .fastigiata和B .racemosa为外类群 ,用最大简约法对杜鹃属的亚属和组间的系统关系进行了分析。结果表明 :1)杜鹃属是一个单系类群 ,叶状苞亚属为杜鹃属的基部类群 ;2 )杜香属确应归并到杜鹃属中 ,且与有鳞杜鹃亚属有较近的亲缘关系 ;3)有鳞杜鹃亚属和杜香构成一个单系分支 ,该分支是其余无鳞杜鹃花的姐妹群 ;4 )由无鳞杜鹃花组成的一个分支的内部支持率较低 ,其中常绿杜鹃亚属和映山红亚属均为内部支持率很高的单系类群 ,而羊踯躅亚属和马银花亚属均为多系类群 ;5 )在马银花亚属中 ,长蕊杜鹃组和马银花组均分别得到强烈支持 ,马银花组与异蕊杜鹃亚属可能构成姐妹群关系 ,异蕊杜鹃亚属和马银花组组成的一个分支可能与映山红亚属构成姐妹群关系。  相似文献   

10.
中国锦鸡儿属的分子系统发育   总被引:1,自引:0,他引:1  
测定了中国锦鸡儿属Caragana各属下分类群20个代表种的ITS、trnL-F和trnS-G序列.基于3种DNA片段的单独分析所获得的系统发育树具有相似的拓扑结构;3种片段的合并分析提高了各分支的支持度,并获得了相似的系统发育树.落轴亚属subgen.Caragana的种类构成了一个在系统树上首先分化出来的单系分支,与形态特征和地理分布的研究一致.短齿系ser. Occidentales和长齿系ser. Bracteolatae的代表种构成了1个单独的分支,因此短齿系应被放入长齿系所属刺叶组sect.Longspina 而不是针刺组sect.Spinosae或sect.Pruinosa.分子系统学证据支持依据叶片宽窄在掌叶组sect.Frutescentes中再划分2个系的形态学研究结论;但Ser.Dasyphyllae和针刺系ser.Spinosae的亲缘关系较近,系统发育分析的结果似乎不支持在针刺组中单独划分2个系.宿轴类的物种聚成一个单系的分支,因此应被处理为一个组--鬼箭组sect.Jubatae;荚果里面被毛和无毛的种类各自构成2个小支,支持依据该特征在组下分系.系统树显示Sanczir定义的sect.Tragacanthoides然为多系类群,应将该组中所包含的刺叶组、针刺组、和鬼箭组的种类划分出来.基于ITS的遗传距离表明卷叶锦鸡儿C. ordosica与藏锦鸡儿C, tibetica应该是2个不同的种.  相似文献   

11.
? Premise of the study: The classification of the genus Salix has historically been intrinsically difficult due to its propensity toward plasticity and high variation in diagnostic morphological characters. We investigated leaf epidermal characteristics, focusing on the stomatal apparatus because it may provide critical insights into the evolution and taxonomy of Salix and its closely related genera. ? Methods: Light microscopy was used to examine the leaf epidermal features in 32 taxa of Salix. ? Key results: Characters such as shape, size, and density of stomatal complexes were very useful in differentiating Salix species. Variation in features of stomatal apparatus in Salix is wider than previously known. Moreover, the type of stomatal complex proved to be very helpful in discriminating Chosenia as members of the genus Salix. ? Conclusions: The results of the present study support the placement of Chosenia within Salix and the combining of subgenera Chamaetia and Vetrix because of similarities in their unique stomatal apparatus.  相似文献   

12.
中国柳属多雄蕊类群的分支系统学研究   总被引:1,自引:0,他引:1  
张明理 《植物研究》1994,14(3):299-305
应用杨属(Populus)和钻天柳属(Chosenia)分别作为不同的外类群,对中国柳属多雄蕊类群构建了两个分支图。结果表明,钻天柳属、大叶柳和四子柳组(Sect.Tetraspermae)都是较原始的类群。支持建立Toisusu Kimura属。根据分支图和染色体数目资料,多雄蕊类群可划分五个类组。支持方振富教授关于"南方型"和"北方型"的划分以及在东亚有从南方向北方演化的趋势,特别对于中国特有组紫柳组(Sect.Wilsonianae).Sect.Salix和Sect.Subalbae两组的分化应予以承认。  相似文献   

13.
Nucleotide sequences of the chloroplast-encoded rbcL gene were used to examine phylogenetic relationships of the genus Salix together with other allied genera of the family Salicaceae. Phylogenetic analyses of rbcL sequences strongly suggest the monophyly of three commonly recognized genera (Chosenia, Salix, and Toisusu). Two monophyletic groups are recognized within the larger monophyletic group. They do not correspond with any infrageneric taxa proposed so far. With regard to character evolution, it is thought that the reduction of stamen number from more than two stamens to two might occur in at least three lineages and that fused bud scales evolved several times and/or the reverse evolution occurred from fused to free. Some types of pollen surfaces are considered to have evolved independently.  相似文献   

14.
Conoesucidae (Trichoptera, Insecta) are restricted to SE Australia, Tasmania and New Zealand. The family includes 42 described species in 12 genera, and each genus is endemic to either New Zealand or Australia. Although monophyly has been previously assumed, no morphological characters have been proposed to represent synapomorphies for the group. We collected molecular data from two mitochondrial genes (16S and cytochrome oxidase I), one nuclear gene (elongation factor 1-α) (2237–2277 bp in total), and 12 morphological characters to produce the first phylogeny of the family. We combined the molecular and morphological characters and performed both a maximum parsimony analysis and a Bayesian analysis to test the monophyly of the family, and to hypothesize the phylogeny among its genera. The parsimony analysis revealed a single most parsimonious tree with Conoesucidae being a monophyletic taxon and sistergroup to the Calocidae. The Bayesian inference produced a distribution of trees, the consensus of which is supported with posterior probabilities of 100% for 15 out of 22 possible ingroup clades including the most basal branch of the family, indicating strong support for a monophyletic Conoesucidae. The most parsimonious tree and the tree from the Bayesian analysis were identical except that the ingroup genus Pycnocentria changed position by jumping to a neighbouring clade. Based on the assumption that the ancestral conoesucid species was present on both New Zealand and Australia, a biogeographical analysis using the dispersal-vicariance criteria demonstrated that one or two (depending on which of the two phylogenetic reconstructions were applied) sympatric speciation events took place on New Zealand prior to a single, late dispersal from New Zealand to Australia.  相似文献   

15.
The large and diverse genus Salix L. is of particular interest for decades of biological research. However, despite the morphological plasticity, the reconstruction of phylogenetic relationships was so far hampered by the lack of informative molecular markers. Infrageneric classification based on morphology separates dwarf shrubs (subg. Chamaetia) and taller shrubs (subg. Vetrix), while previous phylogenetic studies placed species of these two subgenera just in one largely unresolved clade. Here we want to test the utility of genomic RAD sequencing markers for resolving relationships at different levels of divergence in Salix. Based on a sampling of 15 European species representing 13 sections of the two subgenera, we used five different RAD sequencing datasets generated by Ipyrad to conduct phylogenetic analyses. Additionally we reconstructed the evolution of growth form and analyzed the genetic composition of the whole clade. The results showed fully resolved trees in both ML and BI analysis with high statistical support. The two subgenera Chamaetia and Vetrix were recognized as nonmonophyletic, which suggests that they should be merged. Within the Vetrix/Chamaetia clade, a division into three major subclades could be observed. All species were confirmed to be monophyletic. Based on our data, arctic‐alpine dwarf shrubs evolved four times independently. The structure analysis showed five mainly uniform genetic clusters which are congruent in sister relationships observed in the phylogenies. Our study confirmed RAD sequencing as a useful genomic tool for the reconstruction of relationships on different taxonomic levels in the genus Salix.  相似文献   

16.
A phylogenetic analysis of the family Lemuridae was accomplished using multiple gene partitions and morphological characters. The results of the study suggest that several nodes in the lemurid phylogeny can be robustly resolved; however, the relationships of the species within the genus Eulemur are problematically nonrobust. The genus Varecia is strongly supported as the basal genus in the family. Hapalemur and Lemur catta are strongly supported as sister taxa and together are the sister group to the genus Eulemur. E. mongoz is the most basal species in the genus Eulemur. E. fulvus subspecies form a monophyletic group with three distinct lineages. E. coronatus is strongly supported as the sister taxon to E. macaco. The relationships of E. rubriventer, E. fulvus, and the E. macaco-E. coronatus pair are unresolved. Our combined molecular and morphological analysis demonstrates the lack of influence that morphology has on the simultaneous analysis tree when these two kinds of data are given equal weight. The effects of several extreme weighting schemes (removal of transitions and of third positions in protein-coding regions) and maximum-likelihood analysis were also explored. We suggest that these other forms of inference add little to resolving the problematic relationships of the species in the genus Eulemur.  相似文献   

17.
A ribosomal DNA region, including the entire 5.8S RNA gene and the internal transcribed spacers ITS 1 and ITS 2, was used for studying the phylogeny ofSalicaceae and the relationship betweenSalicaceae andFlacourtiaceae. The length of the ITS regions withinSalicaceae andFlacourtiaceae was similar to that found in other angiosperms. The GC content of both ITS regions was high, varying 62.7-72.2%. The most parsimonious tree clusters the wind-pollinatedChosenia bracteosa among theSalix species, suggesting that it should be included in the genusSalix. The grouping withinSalix leaves subg.Salix as paraphyletic, for which reason the subgeneric division is questionable.Populus was monophyletic and formed a sister group toSalix. The interspecific variation of the ITS sequences was very small inSalicaceae, which is in contradiction to the age of the group according to the evidence from fossil data.Idesia polycarpa fromFlacourtiaceae shows great sequence similarity withSalicaceae, but the analysis of 5.8S rDNA supports monophyly of the four species ofFlacourtiaceae sampled for this study.  相似文献   

18.
对12种34个地理种群的内蒙古棘豆属植物核糖体ITS区段和5.8S基因序列进行比较分析,并采用Maximum Likelihood法构建系统发育树.结果表明:支持棘豆属植物为单系起源,支持《内蒙古植物志》将黄毛棘豆(Oxytropis ochrantha)、多叶棘豆(O.verticillaris)、二色棘豆(O.bicolor)和砂珍棘豆(O.racemosa)归入真棘豆亚属(Subgen.Euoxytropis)轮叶棘豆组(Sect.Baicalia Stell.ex Bunge)的观点.推测多叶棘豆和砂珍棘豆ITS2区段出现的C/T转换可能是其部分种群混杂在其他物种中的主要原因,但基因转换对于系统发育的影响仍尚未可知.研究不支持传统分类学上对鳞萼棘豆(O.squammulosa)与刺叶柄棘豆(O.aci ph ylla)的划分,系统发育树显示二者聚为一支,而非与传统分类学上界定的同组或同亚属植物形成一支;结合植物地理学研究结果,认为刺叶柄棘豆与鳞萼棘豆为地理替代种.推测刺叶柄棘豆可能为多系起源物种.线叶棘豆(O.fili formis)和东北棘豆(O.coerulea与真棘豆亚属物种构成姐妹群,而非单室棘豆亚属植物.研究认为在物种界定过程中,只将少数几个形态学特征作为主要分类依据欠妥.  相似文献   

19.
The molecular phylogeny of the genus Allium which includes eighteen species selected from nine sections was investigated through PCR-RFLP analysis of two chloroplast DNA fragments, including trak gene (approximately 2 520 bp) and rpL16 gene (approximately 1 230 bp). Digestion of these two fragments by 26 restriction endonucleases yielded 303 polymorphic recognition sites, of which 163 were informative sites. The restriction site data matrix were analyzed following the parsimonious Wagner and parsimonious Dollo principle of PAUP ( version 3.1.1 ). Topologically, the most parsimonious Wagner tree constructed by branch-and-bound and heuristic search was similar to the most parsimonious Dollo tree. All the taxa of Allium form a monophyletic group, and five sections based on morphological characters were supported strongly by this result. Sect. Augninum is closely related to Sect. Bromatorrhiza, Sect. Molium is closely related to Sect. Caloscordum. Their reliability was farther confirmed by the bootstrap test very well. In morphology, A. pallasii is closely related to A. caeruleum and belongs to Sect. Haplostemen, A. cepa is closely related to A. galanthum and belongs to Sect. Cepa. But evidence from cladistics of parsimonious tree based on 163 informative sites of PCR-RFLPs showed that they are neither confined to a monophyletic group nor to a natural taxon.  相似文献   

20.
Picoides is the largest genus of woodpeckers and member species are found on most major land masses. Current systematic arrangement of this group, based on morphological, behavioral, and plumage characters, suggests that New World species evolved from a single invasion by a Eurasian common ancestor and that all New World species form a monophyletic group. No clear link has ever been established between the relationships of Old World and New World species other than to infer that the most primitive species is Eurasian. This study employs DNA sequences for two protein-coding mitochondrial genes, cytochrome oxidase I and cytochrome b, to reconstruct phylogenetic relationships among all New World species and several Eurasian representatives of the genus Picoides. A well-resolved mitochondrial gene tree is in direct conflict with proposed species relationships based on nongenetic characters; monophyly among New World species is rejected, the evolution of New World species likely resulted from as many as three independent Eurasian invasions, and Picoides is paraphyletic with two other woodpecker genera, Veniliornis and Dendropicos. These results strongly suggest that this large, cosmopolitan genus is in need of systematic revision in order to reflect evolutionary history.  相似文献   

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