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1.
杨丽娥  孟盈  聂泽龙  孙航 《广西植物》2017,37(7):829-840
茜草属为茜草科模式属,全球约80种,中国有近一半的物种,是茜草属的重要分布中心,大部分隶属于sect.Oligoneura。但是,该组内各种间的形态特征错综复杂,依靠单个性状不易划定种间界限。该研究在全面衡量sect.Oligoneura组内各种间形态特征的基础上,选取该组20种共171份标本,对其3个数量性状和28个定性性状进行聚类分析和主成分分析。结果表明:在主成分分析中,前3个主成分累积贡献率有46.88%,性状的累积贡献率增长并不明显,但该结果仍与聚类分析结果一致。对前3个主成分贡献较大的特征包括叶形(叶长宽比)、叶柄长度、叶脉、每轮叶片数和生活型等,这些形态性状也是该属传统分类学中重要的物种鉴定特征。该研究结果与分子系统发育结果基本一致,支持该组内ser.Chinenses、R.mandersii group、R.angustissima group和R.siamensis group类群的划分,但并不支持ser.Cordifoliae单独成系。sect.Oligoneura内除少数物种外,大部分物种界限均比较清晰。形态计量学研究为sect.Oligoneura甚至茜草属的物种鉴定与划分提供了重要的参考意义。  相似文献   

2.
Sophora tomentosa , the type species of the genus Sophora , is shown by phylogenetic analyses of rbc L and ITS sequence data to be sister to Sophora sect. Edwardsia . S. tomentosa and most of the species from sect. Edwardsia share hypogeal germination, exstipulate leaves, and terete filaments. These species have buoyant seeds, and are distributed by ocean currents throughout the pantropics ( S. tomentosa ) and around southern temperate oceanic islands (sect. Edwardsia ). S. tomentosa differs from the species of sect. Edwardsia by its frutescent growth habit, terminal elongate inflorescence and smooth-walled legume. S. macrocarpa is unusual in sect. Edwardsia as its leaves have stipules, the filaments are winged, and the legume is smooth-walled.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 439–446.  相似文献   

3.
以鼠鞭草(Hybanthus enneaspermus)、鳞隔堇(Scyphellandra pierrei)、雷诺木(Rinorea bengalensis)作为外类群,对堇菜属(Viola)20个类群的trnL trnF序列,17个类群的psbA trnH、rpL16序列以及1个类群的nrDNA ITS序列进行了测定,并从GenBank下载相应的序列,运用最大简约法以及贝叶斯推论法进行系统分析,构建系统发育树。结果表明:堇菜亚属(subgen.Viola)不是一个单系类群,并明确了堇菜属部分组间类群的亲缘关系。本文还结合形态与细胞学证据对堇菜属进行性状演化的推测。结果表明:1)直立茎较匍匐茎、莲座状茎(叶基生)原始;2)托叶边缘长流苏状与托叶1/2~3/4合生分别是鸟嘴柱头堇菜组(sect.Trigonocarpae)和合生托叶组(sect.Adnatae)演化路线的重要性状标志;3)花柱样式从柱头无喙演化至柱头有喙,并由柱头简单演化至柱头复杂,再趋向于柱头简化。  相似文献   

4.
Saxifraga L. is the largest genus in Saxifragaceae and a characteristic component of the herbaceous flora of the temperate and alpine mountains in the Northern Hemisphere. Section Irregulares is a small group of 15–20 species, representing one of the early‐diverged lineages in the genus characterized with unique zygomorphic flowers. We used both nuclear internal transcribed spacer and chloroplast DNA regions (psbA‐trnH, trnL‐F, and matK) to reconstruct its species relationships, estimate divergence times, and infer its historical biogeography. Our phylogenetic results corroborate the monophyly of sect. Irregulares and its sister relationship to sect. Heterisia from North America. The section was well resolved into two lineages corresponding to their morphological features and biogeographic distributions. One represents ser. Stoloniferae including S. stolonifera Curtis and S. nipponica Makino with long‐creeping stolons/rhizomes and small petals with spots and the other comprises the remaining taxa (ser. Rufescentes) which lack long‐creeping rhizomes. Spots on leaves (abaxially spotted vs. abaxially without spots) and spots on petals (without spots vs. with spots) are inferred to be phylogenetically informative within ser. Rufescentes. Divergence time estimates and ancestral area analysis suggested a western North American origin of sect. Irregulares with migration into East Asia by way of the Bering land bridge in the Middle Oligocene. The development of drying and desertification belt in the late Miocene could have played an important role in the subsequent restriction and separation of the north and south lineages within eastern Asia.  相似文献   

5.
鹅观草属部分种的叶表皮微形态特征及其分类学意义   总被引:7,自引:2,他引:5  
在过去叶表皮实验的基础上 ,本文从鹅观草属不同组、系中新增解剖了 1 6个有代表性的种。根据这些种叶片反映的表皮微形态特征 ,进一步证实了鹅观草属共族分属以及属下类群划分的正确性 ,揭示了属中各主要类群的演化水平和系统发育关系。研究结果最后表明 :鹅观草属的半颖组最原始 ,在系统发育中它可能既派生了较进化的小颖组和大颖组 ,又派生了最进化的长颖组 ;在大颖组中 ,齿草系较原始 ,纤毛草系较进化 ,宽叶草系最进化 ,纤毛草系和宽叶草系可能相继起生于齿草系。并且 ,鹅观草属的这种进化关系同过去细胞学和形态学提供的证据是基本一致的。  相似文献   

6.
To clarify the taxonomic status of tomatoes (“Lycopersicon”) and their relationship to the members of sect. Petota of genus Solanum L., organization of the rDNA external transcribed spacer (5′ ETS) was studied in 33 Solanum and “Lycopersicon” species. Phylogenetic reconstruction revealed that three major groups can be distinguished. Non-tuber-bearing species of ser. Etuberosa as well as tuber-bearing Central American diploids appeared as a paraphyletic group. The first of two well-defined clades embraced all tuber-bearing South American species and Central American polyploids. The other clade (named “tomato clade”) contains non-tuber-bearing species of ser. Juglandifolia and tomato species of ser. Neolycopersicon, which appears to be imbedded in sect. Petota. The new 5′ ETS variant D characterized by a cluster of downstream subrepeats is characteristic for the tomato clade. The variant D originated directly from the most ancestral variant A found in ser. Etuberosa and the Central American diploids, whereas variants B and C specific for the tuber-bearing South American species and Central American polyploids represent a parallel lineage of molecular evolution. The sequence analysis demonstrates the existence of an evolutionary trend of parallel multiplication of specific motifs in 5′ ETS in different groups of sect. Petota.  相似文献   

7.
Chloroplast DNA (cpDNA) restriction enzyme site analysis was used to test hypotheses of series and superseries affiliations of 76 taxa, representing 11 of the 13 South American series (material unavailable for two series) of wild potatoes (Solanum sect. Petota) recognized in the latest classification by Hawkes. The cladistic results, combined with those from earlier cpDNA studies of 30 taxa of the Mexican and Central American species (representing eight series; ser. Conicibaccata and ser. Tuberosa have representatives in Mexico and in South America), support four main clades for 17 of the 19 series examined in sect. Petota: (1) the Mexican and Central American diploid species, exclusive of S. bulbocastanum, S. cardiophyllum, and S. verrucosum, (2) S. bulbocastanum and S. cardiophyllum (ser. Bulbocastana, ser. Pinnatisecta), (3) South American diploid species constituting all of ser. Piurana, but also members of ser. Conicibaccata, ser. Megistacroloba, ser. Tuberosa, and ser. Yungasensia, (4) all Mexican and Central American polyploid species (ser. Longipedicellata, ser. Demissa), S. verrucosum (diploid Mexican species in ser. Tuberosa), and South American diploid and polyploid members of ser. Acaulia, ser. Circaeifolia, ser. Commersoniana, ser. Conicibaccata, ser. Cuneoalata, ser. Lignicaulia, ser. Maglia, ser. Megistacroloba, ser. Tuberosa, and ser. Yungasensia. Each of these clades contains morphologically and reproductively very diverse species, and there are no evident morphological features that unite members within a clade to therefore distinguish them. These results strongly suggest a need for a reevaluation of the series and superseries classifications of sect. Petota.  相似文献   

8.
Tsui CK  Sivichai S  Berbee ML 《Mycologia》2006,98(1):94-104
Three genera of asexual, helical-spored fungi, Helicoma, Helicomyces and Helicosporium traditionally have been differentiated by the morphology of their conidia and conidiophores. In this paper we assessed their phylogenetic relationships from ribosomal sequences from ITS, 5.8S and partial LSU regions using maximum parsimony, maximum likelihood and Bayesian analysis. Forty-five isolates from the three genera were closely related and were within the teleomorphic genus Tubeufia sensu Barr (Tubeufiaceae, Ascomycota). Most of the species could be placed in one of the seven clades that each received 78% or greater bootstrap support. However none of the anamorphic genera were monophyletic and all but one of the clades contained species from more than one genus. The 15 isolates of Helicoma were scattered through the phylogeny and appeared in five of the clades. None of the four sections within the genus were monophyletic, although species from Helicoma sect. helicoma were concentrated in Clade A. The Helicosporium species also appeared in five clades. The four Helicomyces species were distributed among three clades. Most of the clades supported by sequence data lacked unifying morphological characters. Traditional characters such as the thickness of the conidial filament and whether conidiophores were conspicuous or reduced proved to be poor predictors of phylogenetic relationships. However some combinations of characters including conidium colour and the presence of lateral, tooth-like conidiogenous cells did appear to be predictive of genetic relationships.  相似文献   

9.
对毛茛科Ranunculaceae铁线莲属Clematis的菝葜叶铁线莲组sect. Naraveliopsis进行了全面修订, 确定此组共含21种1亚种和1变种; 写出此组的分类学简史和地理分布, 并讨论了此组在铁线莲属中的系统位置; 将此组划分为3亚组, 写出分亚组、分种检索表, 以及各种植物的形态描述、地理分布、生长环境等, 并附有多数种的墨线图。根据对此组植物形态特征的分析, 观察到以下重要演化趋势: (1)叶从单叶演变到二回羽状复叶或二回三出复叶; (2)花从两性到单性, 从无退化雄蕊到有退化雄蕊; (3)雄蕊从无毛到有毛; (4)药隔突起从短(0.5-0.7 mm)到长(8.5-10 mm)。根据上述演化趋势,花两性、雄蕊被毛、退化雄蕊存在的荔波铁线莲亚组subsect. Liboenses(1种,特产贵州荔波)和花由两性变为单性的亚组subsect. Macgregorianae(2种,特产菲律宾)被认为是菝葜叶铁线莲组的进化群。在原始的菝葜叶铁线莲亚组subsect. Smilacifoliae(花两性,雄蕊无毛; 18种,广布亚洲热带地区)中,具单叶,花无退化雄蕊,药隔突起较短的菝葜叶铁线莲C. smilacifolia和滇南铁线莲C. fulvicoma被认为是较原始的种,而具三出复叶和退化雄蕊的C. vietnamensis和丝铁线莲C. loureiriana,以及具羽状复叶和长药隔突起(长达10 mm)的C. papillosa等3种则被认为是此亚组的进化种。自中南半岛北部山地向西经云贵高原南部至喜马拉雅东部山区集中分布有菝葜叶铁线莲组的13种植物,这一山区地带被认为是此组的分布中心。在此山区地带中,菝葜叶铁线莲的分布区和滇南铁线莲的分布区重叠部分的山区可能是此组的起源中心。  相似文献   

10.
The Liolaemus lineomaculatus section is a geographically widely distributed group of lizards from the Patagonian region of southern South America, and includes 18 described species representing the most southerly distributed Liolaemus taxa (the genus includes 228 species and extends from Tierra del Fuego north to south-central Peru). Despite high species diversity, the phylogenetic relationships of this section are unknown. In the present work we sampled all described species in the L. lineomaculatus section as well as currently undescribed candidate species to reconstruct the first complete phylogenetic hypothesis for the clade. Our data set included four anonymous nuclear loci, three nuclear protein-coding loci, and two mitochondrial genes. We compared results obtained with three different phylogenetic methods for the concatenated data set (Maximum Parsimony, Maximum Likelihood and Bayesian Inference) with a coalescent-based species tree approach (BEST), and recovered congruent, strongly-supported topological arrangements across all methods. We identified four main clades within the L. lineomaculatus section: the lineomaculatus, magellanicus, somuncurae, and kingii+archeforus groups, for which we estimated divergence times. We discuss the taxonomic implications of these results and how the future integration of phylogeographic, niche modeling and morphological approaches will allow testing biogeographical hypotheses in this clade.  相似文献   

11.
12.
We investigated the phylogenetic relationships among 20 species of Oriental torrent frogs in the genus Amolops and its allies from China and Southeast Asia based on 1346-bp sequences of the mitochondrial 12S and 16S rRNA genes. Oriental species of the tribe Ranini form a monophyletic group containing 11 clades (Rana temporaria + Pseudoamolops, R. chalconota, four clades of Amolops, Meristogenys, three clades of Huia species, and Staurois) for which the phylogenetic relationships are unresolved. The genus Amolops consists of southern Chinese, southwestern Chinese, Thai, and Vietnamese-Malaysian lineages, but their relationships are also unresolved. The separation of southern and southwestern lineages within China conforms to previous morphological and karyological results. Species of Huia do not form a monophyletic group, whereas those of Meristogenys are monophyletic. Because P. sauteri is a sister species of R. temporaria, distinct generic status of Pseudoamolops is unwarranted.  相似文献   

13.
Carthamus (Asteraceae) includes both crop (Carthamus tinctorius, safflower) and weedy species. Despite previous studies, many outstanding questions remain regarding the phylogenetic surroundings of safflower, especially in relation to weedy species. Here we investigated relationships within Carthamus using a tiered approach examining sequence and microsatellite data. First, nuclear and chloroplast sequences were analyzed from 37 accessions of 16 species. Maximum parsimony, maximum likelihood, and Bayesian inference confirm two well supported clades, corresponding to sect. Atractlyis and sect. Carthamus, the latter of which includes safflower. Because sequence data provided limited resolution within the clades, microsatellite markers were used to investigate relationships within sect. Carthamus. Both sequence and microsatellite data reveal that most traditionally recognized species are not monophyletic. Microsatellite data indicate that Carthamus palaestinus is the closest relative of cultivated safflower.  相似文献   

14.
Maximum parsimony and maximum likelihood phylogenetic trees were constructed for 21 taxa of Lophozia s. str. and the related genera, Schistochilopsis (5 species), Protolophozia elongate, and Obtusifolium obtusum based on pooled nuclear ITS 1-2 and chloroplast trnL-F DNA sequences. The trees were characterized by similar topology. It was demonstrated that the genus Lophozia s. str. was monophyletic, excluding L. sudetica, which deserved isolation into a distinct cryptic genus. The species distribution among the clades disagreed with the sections distinguished based on anatomical and morphological data. The relationships within the genus Schistochilopsis were consistent with the sectioning of the genus, based on morphological characters. Analysis of molecular data provided more precise definition of the systematic position of a number of taxa. Small genetic divergence of geographically distant forms was demonstrated.  相似文献   

15.
The sequences of chloroplast trnL trnF (20 species), psbA trnH(17 species), rpL16 (17 species) and ITS(one species) regions of the genus Viola were analyzed for phylogenetic relationships in the genus with the maximum parsimony (MP) and Bayesian inference (BI) analyses. Hybanthus enneaspermus, Scyphellandra pierrei and Rinorea bengalensis were used as outgroups. Additional sequences corresponding to the same DNA regions for the other taxa in Viola were downloaded from GenBank. The phylogenetic tree indicated that subgenViola is not monophyletic. Moreover, some intrageneric relationships in Viola were clarified. Combining sequences with morphological characters and chromosome number, the inference of morphological evolution in Viola was put forward. It was inferred that: 1) erect stems might well be more primitive than stolons and rosettes; 2) long fimbriate margin in stipules and stipules with 1/2-3/4 adnate part might represent distinctive evolutionary trends of sectTrigonocarpae and of sectAdnatae respectively; 3) species with stigmatic beaks might have been derived from ancestors without beaks; simple structure stigmas transformed into complex structure stigmas, and then transformed back to simple stucture patterns.  相似文献   

16.
The taxonomic validity of the genus Hydropuntia Montagne (1843) (including Polycavernosa) within the Gracilariaceae (Gracilariales, Rhodophyta) is controversial. Morphological characters that define species of Hydropuntia are said to be variable and to overlap with those of Gracilaria. Here we present a global phylogenetic study of the family based on a Bayesian analysis of a large rbc L DNA sequence dataset indicating that the genus Hydropuntia forms a well supported monophyletic clade within the family, and recognize Hydropuntia as a genus distinct from Gracilaria. We also conducted smaller phylogenetic analyses in which thirty four Hydropuntia rbc L sequences resulted in two major clades within the genus, comprising a Caribbean clade and an Indo-Pacific clade. Diagnostic reproductive stages that separate these two clades will be illustrated.  相似文献   

17.
以鼠鞭草(Hybanthus enneaspermus)、鳞隔堇(Scyphellandra pierrei)、雷诺木(Rinorea benga-lensis)作为外类群,对堇菜属(Viola)20个类群的trnL-trnF序列,17个类群的psbA-trnH、rpL16序列以及1个类群的nrDNAITS序列进行了测定,并从GenBank下载相应的序列,运用最大简约法以及贝叶斯推论法进行系统分析,构建系统发育树。结果表明:堇菜亚属(subgen. Viola)不是一个单系类群,并明确了堇菜属部分组间类群的亲缘关系。本文还结合形态与细胞学证据对堇菜属进行性状演化的推测。结果表明:1)直立茎较匍匐茎、莲座状茎(叶基生)原始;2)托叶边缘长流苏状与托叶1/2~3/4合生分别是鸟嘴柱头堇菜组(sect. Trigonocarpae)和合生托叶组(sect. Adnatae)演化路线的重要性状标志;3)花柱样式从柱头无喙演化至柱头有喙,并由柱头简单演化至柱头复杂,再趋向于柱头简化。  相似文献   

18.
Tordylium is a medium‐sized genus characterized by an annual habit, 1–3‐pinnate leaves, dorsally compressed mericarps, and thickened mericarp margins. Eighteen Tordylium species occur in Turkey, of which seven are endemic. Although the morphology of the genus is well known, evolutionary relationships among its species have never been evaluated. In this study, phylogenetic relationships within Tordylium are investigated using parsimony analysis based on morphological data from 17 ingroup and 15 outgroup taxa from Turkey. The results indicate that Tordylium is paraphyletic due to the inclusion of Ormosciadium. Further, it suggests that Hasselquistia, Condylocarpus and Ainsworthia are nested within Tordylium, confirming their current taxonomic treatment as synonyms. Within the paraphyletic Tordylium, two major clades are apparent, but these clades are not compatible with the current sub‐generic classification. Tordylium lanatum, T. aegyptiacum and T. elegans, which have dimorphic mericarps, form a monophyletic subclade. In addition, it is suggested that T. aegaeum should be accepted as a distinct species rather than as a synonym of T. pestalozzae.  相似文献   

19.
Pinnate compound leaves have laminae called leaflets distributed at intervals along an axis, the rachis, whereas simple leaves have a single lamina. In simple- and compound-leaved species, the PHANTASTICA (PHAN) gene is required for lamina formation. Antirrhinum majus mutants lacking a functional gene develop abaxialized, bladeless adult leaves. Transgenic downregulation of PHAN in the compound tomato (Solanum lycopersicum) leaf results in an abaxialized rachis without leaflets. The extent of PHAN gene expression was found to be correlated with leaf morphology in diverse compound-leaved species; pinnate leaves had a complete adaxial domain of PHAN gene expression, and peltate leaves had a diminished domain. These previous studies predict the form of a compound-leaved phan mutant to be either peltate or an abaxialized rachis. Here, we characterize crispa, a phan mutant in pea (Pisum sativum), and find that the compound leaf remains pinnate, with individual leaflets abaxialized, rather than the whole leaf. The mutant develops ectopic stipules on the petiole-rachis axis, which are associated with ectopic class 1 KNOTTED1-like homeobox (KNOX) gene expression, showing that the interaction between CRISPA and the KNOX gene PISUM SATIVUM KNOTTED2 specifies stipule boundaries. KNOX and CRISPA gene expression patterns indicate that the mechanism of pea leaf initiation is more like Arabidopsis thaliana than tomato.  相似文献   

20.
Carex sect. Confertiflorae s.l. is a medium-sized species group (ca. 40 species) with its center of diversity in E Asia (China and Japan). According to morphological traits, the section has been proposed to split into two sections (sects. Confertiflorae sensu Ohwi and Molliculae Ohwi) up to five different ones (sects. Confertiflorae s.s., Molliculae, Dispalatae Ohwi, Ischnostachyae Ohwi, and Alliiformes Akiyama). Recent phylogenetic reconstructions showed Confertiflorae s.l. not to be monophyletic, as species traditionally considered part of it were found to belong to other clades, whereas species traditionally ascribed to other sections were nested within it. In this study, we investigated the phylogenetic structure, morphological affinities, and biogeographic history of sect. Confertiflorae s.l. We employed a taxon-based approach to explore the morphological affinities of the species considered in sect. Confertiflorae and compared the micromorphology of the nutlets of almost all the taxa using SEM. We included 40 samples representing 31 species/subspecies of sect. Confertiflorae s.l. and used two nuclear (ETS and ITS) and three plastid (trnL-F, matK, and rpl32-trnL UAG) molecular markers to reconstruct the phylogeny of the group. The phylogenetic analyses confirmed the polyphyly of sect. Confertiflorae s.l., whose representatives were found within five distinct clades. From these, two clades, sect. Confertiflorae and sect. Molliculae, were found to be closely related and contained the majority of the species. The composition of the two clades agreed with the morphological structure of the group, and we confirmed an exclusive combination of features (namely color of basal sheaths, presence of bract sheath, peduncle of lowest spike, inflorescence sex distribution, shape of pistillate glume apex, and color and veins of utricle, among others) characterizing each of the two clades. The origin of the two clades was found to be in the early Pliocene; however, the majority of the diversification events within each clade took place during the Pleistocene. This illustrates that although Asia has been regarded as having little potential ecological space for Carex to diversify due to its climate stability, groups of sedges sub-endemic from that area may have a fairly recent origin related to glaciations. We proposed the rearrangement of sect. Confertiflorae as previously conceived as three independent sections: the monotypic Alliiformes, sect. Molliculae, and sect. Paludosae.  相似文献   

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