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1.
23 widespread apomictic Alchemilla microspecies occurring in Estonia are analyzed to investigate whether the species and higher rank taxa are distinct, how variable these taxa are and which characters distinguish them better. Cluster analysis, discriminant analysis, analysis of variance, principal component analysis and continuum analysis are used for data processing. The characters form four correlative groups, describing (i) vegetative and (ii) generative parts of the plant body, (iii) hairiness characters and, (iv) leaf teeth measurements. The best characters according to analysis of variance for disünguishing species are hairiness characters, but often they distinguish only few species very clearly and cannot be used for the remaining ones. Hence the other characters cannot be excluded. From the studied species only A. plicata, A. semilunaris and A. lindbergiana are significantly distinct from all others. The remaining ones form a complicated network of mutually indistinct pairs. Higher rank taxa — sections and series according to Rothmaler, Fröhner and Yuzepchuk are better separated, containing very few mutually indistinct pairs. Results from species centroids' clustering are most congruent with Fröhner's system, but still some changes seem to be necessary and a corrected system is proposed here. Section Plicatae is split into two series: Pubescentes and Barbulatae , sections Alchemilla, Ultravulgares and Decumbentes are joined as three series of section Hirsutae , and A. filicaulis is moved from section Plicatae to section Coriaceae. Coriaceae should also be split into three series: Exuentes (A. filicaulis), Glabricaules (A. glabricaulis) and Coriaceae (other species).  相似文献   

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Alchemilla boluensis from the west Black Sea region of Turkey is described as a species new to science and illustrated. It belongs to the section Alchemilla , subsection Calycanthum and series Elatae , and is closely related to A. amoena , from which it mainly differs in its stem and leaf features.  相似文献   

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Apomictic microspecies, for example those of the genus Alchemilla, are often difficult to distinguish. Still, their differences are thought to be persistent due to apomixis. Apomicts are argued to have general-purpose genotypes. The present study aims to assess the variation of morphological characters of Alchemilla depending on environmental conditions both in nature and experimentally; to evaluate the efficacy of characters for identifying the different microspecies; to assess the similarity of different microspecies; and to determine if Alchemilla microspecies have general-purpose genotypes that are not dependent on environmental conditions. The variability of selected characters in seven microspecies of Alchemilla was studied in nature and five microspecies were grown in a common garden experiment. The growing conditions of the latter were subjected to various manipulations (fertilization, shading and irrigation). Typical natural habitats of Alchemilla exhibited only small differences. Environmental conditions therefore had little effect on morphological characters. Neither cultivation in the common garden nor manipulation of conditions therein had a significant impact on the discrimination of microspecies. However, the metric characters were larger in the garden relative to those observed in nature, particularly under fertilization. Fertilization affected most characters, whereas shading and irrigation did not. The most effective characters for discriminating between microspecies were the ratios of the metric characters. Two species pairs: A. vulgaris and A. micans, as well as A. glaucescens and A. hirsuticaulis were morphologically close; however, the species within these pairs could still be distinguished. The morphological characters of Alchemilla microspecies were only slightly dependent on the environmental conditions.  相似文献   

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Morphological data were gathered from 126 herbarium specimens representing ten species of Psophocarpus. Specimens were scored for 29 vegetative, 46 inflorescence, 16 legume and six seed characters. The data were analysed using cluster analysis and ordination and the results used to produce an overall phenetic classification. The proposed classification includes a tenth species recently distinguished, but undescribed by Verdcourt. Keys are provided to the subgenera and sections, as well as the ten taxa recognized and the classification is discussed in relation to previous classifications of the genus.  相似文献   

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Alchemilla, commonly called “lady's mantle”, is a genus of herbaceous perennial plants belonging to the family Rosaceae. The species Alchemilla velebitica is found only in Southern Europe, like in the Croatian National Park Northern Velebit. Its benefits, such as a astringent and emmenagogue activity as well as wound healing are correlated to the organic compounds found in the plant, but also certain trace elements are known to reduce skin lesions, such as zinc, selenium, copper, manganese, silicon and lithium.Thus the objective of the present study was the elemental characterization of leaves, blossoms and roots of A. velebitica. After acidic microwave assisted digestion the concentrations of selected essential and trace elements were determined by inductively coupled plasma – atomic emission spectrometry and inductively coupled plasma – mass spectrometry. Other minor elements, such as Al, B, Cu, Fe, Mn, Sr and Zn are also found in leaves, blossoms and roots with contents in μg/kg range. The preparation of decoctions and the extraction yields of the elements of interest are calculated.  相似文献   

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Agaricus section Xanthodermatei comprises a group of species allied to A. xanthodermus and generally characterized by basidiomata having phenolic odors, transiently yellowing discolorations in some parts of the basidiome, Schaeffer's reaction negative, and mild to substantial toxicity. The section has a global distribution, while most included species have distributions restricted to regions of single continents. Using specimens and cultures from Europe, North America, and Hawaii, we analyzed DNA sequences from the ITS1+2 region of the nuclear rDNA to identify and characterize phylogenetically distinct entities and to construct a hypothesis of relationships, both among members of the section and with representative taxa from other sections of the genus. 61 sequences from affiliated taxa, plus 20 from six (or seven) other sections of Agaricus, and one Micropsalliota sequence, were evaluated under distance, maximum parsimony and maximum likelihood methods. We recognized 21 discrete entities in Xanthodermatei, including 14 established species and 7 new ones, three of which are described elsewhere. Four species from California, New Mexico, and France deserve further study before they are described. Type studies of American taxa are particularly emphasized, and a lectotype is designated for A. californicus. Section Xanthodermatei formed a single clade in most analyses, indicating that the traditional sectional characters noted above are good unifying characters that appear to have arisen only once within Agaricus. Deep divisions within the sequence-derived structure of the section could be interpreted as subsections in Xanthodermatei; however, various considerations led us to refrain from proposing new supraspecific taxa. The nearest neighbors of section Xanthodermatei are putatively in section Duploannulati.  相似文献   

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The new species Alchemilla semidivisa (Rosaceae) is described from Møre og Romsdal in west-central Norway. A. semidivisa belongs to the series Splendentes , until now only known from the Alps, the Pyrenees, the Faeroes and Iceland, and is probably closely related to A. faeroënsis. It has been found in 11 localities within a very small area. Large populations have been found at four sites, of which three are near waterfalls. Flora Nordica notes 32.  相似文献   

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Cladistics has become a widely used method for phylogenetic reconstruction.Because of rapid improvement Of cladistic theories and methodologies,and application of new data,especially,molecular data,it is becoming realistic to reconstruct phylogenies of organisms,and to establish natural classifications based on these phylogenies.This paper reviews some current cladistic theories and methods in a practical way,such as choosing characters,defining character states,polarizing characters,analyzing data matrices, calculating consensus cladograms,choosing among multiple equally most parsimonious cladograms,estimating reliability of cladograms,and applying cladograms to classification, character evolution,and biogeography. Based on 36 morphological characters.a parsimony analysis of 12 species representing six sections in subgenus Lindera and an outgroup species from subgenus lteodaphne of the genus Lindera(Lauraceae)was conducted.The results suggest a close relationship between section Lindera and section Sphaerocarpae,which is different from the previous phylogenetic hypothesis within the genus.In the strict consensus cladogram,two species,L.megaphylla and L.chienii,from section Cupuliformes are in the most primitive and the most advanced clades respectively,indicating that the section is polyphyletic.The cladogram also suggests that section Lindera be a polyphyletic group.  相似文献   

12.
A new species of Alchemilla L. (Rosaceae), A. reflexa Frost‐Ols., is described and illustrated. A. reflexa is characterized by deflexed indumentum on petioles and stems, orbicular leaves with imbricate basal lobes and crimson‐magenta coloured basal stipules. It is distributed in the Massif Central, France, where it is widespread, and in northeastern Pyrenees (déps. Ariège and Aude). A. reflexa is compared with two species previously recorded from the Massif Central with doubt, A. exigua Buser and A. strigosula Buser and with A. filicaulis Buser that can be misidentified as A. reflexa in the field. An introduction to past treatments of Alchemilla in the Massif Central is provided as well as a discussion of some morphological elements used for delimiting Alchemilla taxa.  相似文献   

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本文概述了当前分支系统学研究中涉及的主要理论和方法,包括性状的选取、性状状态和极性的确定、数据矩阵的分析计算、结果分支图的处理、分支图可靠性的评价及分支图的应用。本文同时以华东地区樟科山胡椒属Linderal2个种的分支系统学研究为例,讨论了用形态性状进行分支系统学研究中可能遇到的问题,也揭示了一些分支系统学与传统的系统学在应用性状推导进化关系上的不同点。对这12个种的分支系统学研究得出了一些不同于传统系统学方法所推测的山胡椒属内的系统发育关系,如分支系统学研究显示山胡椒组和球果组很近缘。在严格一致性分支图上,杯托组的黑壳楠和江浙山胡椒分别位于最原始和最进化的分支,表明这个组是复系类群。分支图也显示山胡椒组可能是复系类群。  相似文献   

15.
Morphological variation and taxonomic continuum of 110 specimens of Bromus arvensis, B. japonicus and B. squarrosus were analysed to assess the morphological variability of these close taxa. The importance of every morphological character was estimated by the GLM procedure. Stepwise discriminant analysis was used in order to find a set of morphological characters that maximises differences among the species. According to this, the most important characters appeared to be the length of anthers, width of lemma and lemma margin angle shape. The most important characters for the determination of Bromus arvensis was the length of anthers and for B. squarrosus width of lemma. According to the UPGMA cluster analysis, canonical discriminant, classificatory discriminant and principal component analyses, all specimens were separated into three moderately distinct groups which corresponded to the three traditional species. The study showed that qualitative characters were the best for the delimitation of the tax a by statistical analyses and demonstrated the incongruity between the pattern of morphological and genetic (allozyme) variation among the three Bromus species.  相似文献   

16.
槭树科植物广义形态学性状分支分析   总被引:4,自引:0,他引:4  
通过45个广义的形态学性状对槭树科(Aceraceae)尤其是槭属(Acer L.)的主要类群做了分支分析,结果显示:1)槭属内由于各类群分布着较多的同塑性状状态,而难以为属下组间关系的解决提供更多有价值的信息;通过对具体的性状状态分布分析显示,对于象槭属这样在形态上分化较大的类群,由于多数分类性状在不同类群间经历了平行和逆转演化,因而在较低分类阶元水平很难选择合适的性状来通过分支分析构建其系统发育;2)鸡爪槭组(section Palmata)作为整个槭属的基部类群,虽然支持率较低,但与其它类群相比在槭属内维持了较多的原始性状;3)金钱槭属(Dipteronia Oliv.)的两个种作为单系得到了100%的靴带支持,且和槭属作为姐妹群也得到了较好的支持。  相似文献   

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Amanita curtipes and A. ponderosa are two Mediterranean taxa sharing a number of morphological features as well as their habitat. Their synonymy or variety status has been proposed by several authors. To clarify this taxonomic issue we have sequenced the D1-D2 domains of the 28S rRNA gene as well as the complete ITS1-5.8S-ITS2 region of several specimens of the two species collected in Spain, and aligned these sequences with those from other Amanita species. Molecular phylogenetic analysis based on the two regions revealed that A. ponderosa and A. curtipes are clearly distinct species. The distribution of Amanita species in the phylogenetic trees was consistent with the division of the genus in subgenera and sections as proposed by previous authors. Sequences of A. ponderosa and A. curtipes were grouped in a monophyletic cluster together with other species of the section Amidella. However, A. ponderosa was closer to other species in the section, such as A. peckiana and A. volvata, than to A. curtipes. We also indicate the macromorphological characters that are most useful to reliably distinguish A. ponderosa and A. curtipes.  相似文献   

18.
Desert truffles belonging to Terfezia are well known mycorrhizal members of the mycota of the Mediterranean region and the Middle East. We aimed to test (i) whether the morphological criteria of Terfezia species regularly collected in Spain enable their separation and (ii) whether the previously hypothesized edaphic/biotic specificity of one group could be confirmed by study of a larger number of specimens. The species T. arenaria and T. claveryi can be identified unambiguously by morphological characters. We consider T. leptoderma as a distinct species while several lineages of similar spiny spored Terfezia truffles with cellular peridium were detected that have no obvious anatomical differences. Several species treated generally as synonyms of T. olbiensis have been described in this group, and because they cannot be unambiguously assigned to separate lineages we propose to consider the group as the T. olbiensis species complex. A high level of intrasporocarpic variation of the nrDNA ITS was detected in the T. olbiensis species complex, especially in one of its lineages. We detected no exclusive specificity to either plant associates or soil, except in T. leptoderma, which was associated with Quercus spp. and cistaceous plants on acidic soils. Nevertheless the clades showed a tendency either to associate with Quercus/Helianthemum/Cistus or Pinus hosts. Specimens having distinct anatomical features, reticulate spores and cellular peridium formed a separate group in the molecular phylogenetic analyses of nrDNA ITS and LSU regions; for these specimens we propose a new species, Terfezia alsheikhii sp. nov.  相似文献   

19.
黄耆属簇毛黄耆亚属系统学研究   总被引:1,自引:0,他引:1  
簇毛黄耆亚属以其柱头上具簇毛等形态特征与黄耆属其它类群相区别,约含49种(变种)。主要分布在青藏高原及其邻近地区,绝大多数种类分布于横断山区。本文基于形态特征和分支系统学方法分析亚属内种系发生关系。结果表明,49种(变种)可分为9组。其中双小苞组Sect.Bibracteolati含种类最多,是一个并系类群。借助于分支图,分析了6个较重要的鉴定特征的演化,习性,茎的着生方式,小苞片,果实形态,柱头具簇毛,果实膨胀状况等。最后作出了这个亚属的一个分类纲要。  相似文献   

20.
Specimens from the exsiccatae Phycotheca BorealiAmericana number 698 are shown to represent two distinct species. One of them, formerly known as Callithamnion halliae, is transferred to Aglaothamnion on the basis of its uninucleate cells. The specimens exhibit distichous branching and are ecorticate. A lectotype is proposed for one of the P.B.-A. #698 specimens displaying these characters . Aglaothamnion halliae ( Collins) comb. nov. is an earlier name for Aglaothamnion westbrookiae Rueness et L'Hardy-Halos. The second species, together with specimens of P.B.-A. #1896, has radial branching and corticated axes and is described herein as a new species , Aglaothamnion collinsii. The binomial Aglaothamnion boergesenii ( Aponte et Ballantine ) L'Hardy-Halos et Rueness in Aponte, Ballantine, et J. Norris is validated. A key to the tropical and warm-temperate western Atlantic species of Aglaothamnion is presented .  相似文献   

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