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1.
DNA sequences of the 5' end of the chloroplast ndhF gene for 15 species of Caryophyllaceae have been analyzed by parsimony and neighbor-joining analyses. Three major clades are identified, with little or no support for monophyly of traditionally recognized subfamilies. The first of the three major clades identified (Clade I) is constituted by part of the subfamily Paronychioideae. It includes members of the tribe Paronychieae and members of tribe Polycarpeae. The second (Clade II) contains members of the Paronychieae exclusively. Tribe Paronychieae is thus apparently polyphyletic and tribe Polycarpeae is at least paraphyletic. The third clade (Clade III) includes members of subfamilies Alsinoideae and Caryophylloideae along with the genus Spergularia. The genus Scleranthus is also part of Clade III, while Drymaria groups with the other genera of tribe Polycarpeae in Clade II. We conclude that morphological characters previously used to delimit subfamilial groupings in the Caryophyllaceae are apparently unreliable estimators of phylogeny.  相似文献   

2.
The karyotypes of 16 species and one variety representing nine genera in the Ranunculaceae were analysed in order to obtain information on the placement of the genera Beesia and Eranthis at tribal rank in the family. Those of Beesia , Anemonopsis , Souliea , Cimicifuga , Actaea and Eranthis were found to be very similar to each other, but remarkably different from those of Caltha , Calathodes , Megaleranthis and Trollius with respect to chromosome size and morphology. From cytological data it is clearly evident that Beesia and Eranthis have a much closer affinity to Anemonopsis , Souliea , Cimicifuga and Actaea in the tribe Cimicifugeae than to Caltha , Calathodes , Megaleranthis and Trollius , which generally have been placed together in a single tribe, albeit with different tribal names such as Caltheae, Trollieae and Helleboreae. Therefore, Beesia and Eranthis may find better placement in the tribe Cimicifugeae. The long-presumed, mainly morphology-based close affinity between Eranthis and Helleborus is not supported by both cytological and palynological data. Cytologically, both Actaea and Eranthis appear to be the specialized genera in the Cimicifugeae, through having the most asymmetrical karyotypes in this tribe. Our results strongly support the recent re-definition of the tribe Actaeeae (as Cimicifugeae) to include Beesia and Eranthis , based on maximum parsimony analysis performed separately on molecular data.  © 2006 The Linnean Society of London. Botanical Journal of the Linnean Society , 2006, 150 , 267–289.  相似文献   

3.
Phylogeny and infrageneric relationships were reconstructed for Korean Viola(Violaceae)using eight chloroplast sequences: the atpB-rbcL intergenic spacer,the atpF-H intergenic spacer,the matK gene,the psbA-trnH intergenic spacer,the psbK-I intergenic spacer,the rpl16 intron,the rpoC1 exon 2,and the trnL-trnF regions.The combined analyses of the eight chloroplast regions suggest that sections Dischidium and Chamaemelanium are monophyletic,whereas section Nomimium is paraphyletic; sections Dischidium and Chamaemelanium form a clade with subsections Hypocarpae and Trigonocarpae of section Nomimium,but unresolved within the clade; two subsections(subsects.Bilobatae and Vaginatae)of section Nomimium form a clade and are placed between the stem and stemless species group; and subsection Patellares of section Nomimium is monophyletic,and Viola dissecta is diverged first in the clade with high support(BS = 100,PP = 100).Our present results support the subsectional grouping based on morphological characteristics,although discordance remained at the series level.  相似文献   

4.
Population bottlenecks are often invoked to explain low levels of genetic variation in natural populations, yet few studies have documented the direct genetic consequences of known bottlenecks in the wild. Empirical studies of natural population bottlenecks are therefore needed, because key assumptions of theoretical and laboratory studies of bottlenecks may not hold in the wild. Here we present microsatellite data from a severe bottleneck (95% mortality) in an insular population of song sparrows (Melospiza melodia). The major findings of our study are as follows: (i) The bottleneck reduced heterozygosity and allelic diversity nearly to neutral expectations, despite non-random survival of birds with respect to inbreeding and wing length. (ii) All measures of genetic diversity regained pre-bottleneck levels within two to three years of the crash. This rapid recovery was due to low levels of immigration. (iii) The rapid recovery occurred despite a coincident, strong increase in average inbreeding. These results show that immigration at levels that are hard to measure in most field studies can lead to qualitatively very different genetic outcomes from those expected from mutations only. We suggest that future theoretical and empirical work on bottlenecks and metapopulations should address the impact of immigration.  相似文献   

5.
This paper explores self-perceived mate value (SPMV), and its association with self-esteem, in eight cultures. 1066 participants, from 8 cultural groups in 7 countries, rated themselves on 24 SPMVs and completed a measure of self-esteem. Consistent with evolutionary theory, women were more likely to emphasise their caring and passionate romantic nature. In line with previous cross-cultural research, characteristics indicating passion and romance and social attractiveness were stressed more by respondents from individualistic cultures, and those higher on self-expression (rather than survival) values; characteristics indicative of maturity and confidence were more likely to be mentioned by those from Traditional, rather than Secular, cultures. Contrary to gender role theory, societal equality had only limited interactions with sex and SPMV, with honesty of greater significance for male self-esteem in societies with unequal gender roles. These results point to the importance of cultural and environmental factors in influencing self-perceived mate qualities, and are discussed in relation to broader debates about the impact of gender role equality on sex differences in personality and mating strategies.  相似文献   

6.
The wood sorrel family, Oxalidaceae, is mainly composed of annual or perennial herbs, a few shrubs, and trees distributed from temperate to tropical zones. Members of Oxalidaceae are of high medicinal, ornamental, and economic value. Despite the rich diversity and value of Oxalidaceae, few molecular markers or plastomes are available for phylogenetic analysis of the family. Here, we reported four new whole plastomes of Oxalidaceae and compared them with plastomes of three species in the family, as well as the plastome of Rourea microphylla in the closely related family Connaraceae. The eight plastomes ranged in length from 150,673 bp (Biophytum sensitivum) to 156,609 bp (R. microphylla). Genome annotations revealed a total of 129–131 genes, including 83–84 protein-coding genes, eight rRNA genes, 37 tRNA genes, and two to three pseudogenes. Comparative analyses showed that the plastomes of these species have minor variations at the gene level. The smaller plastomes of herbs B. sensitivum and three Oxalis species are associated with variations in IR region sizes, intergenic region variation, and gene or intron loss. We identified sequences with high variation that may serve as molecular markers in taxonomic studies of Oxalidaceae. The phylogenetic trees of selected superrosid representatives based on 76 protein-coding genes corroborated the Oxalidaceae position in Oxalidales and supported it as a sister to Connaraceae. Our research also supported the monophyly of the COM (Celastrales, Oxalidales, and Malpighiales) clade.  相似文献   

7.
The genus Dasypyrum (or Haynaldia) consists of two species, D. villosum and D. breviaristatum. However, the genomic relationships between these two species remain unclear. The objective of this study was to provide molecular phylogenic and cytological evidence on the evolutionary relationships of the genus Dasypyrum. Sequences of Chloroplast DNA (cpDNA) and α-gliadin genes both support the hypothesis that diploid D. breviaristatum is the progenitor of tetraploid D. breviaristatum, and the diploid D. villosum and D. breviaristatum evolved parallel from an ancestral species. Genomic and fluorescence in situ hybridization using ribosomal DNA and rye repetitive DNA sequence as probes also indicated that tetraploid D. breviaristatum originated from diploid D. breviaristatum.  相似文献   

8.
DNA from 22 different species, accessions, cultivars and lines included in theSecale genus were analyzed by the polymerase chain reaction (PCR), using as primers five pairs of oligonucleotides derived from specific sequences. A total of 42 amplified bands were considered, and some of them appeared to be potentially useful as molecular markers for some of the analyzed groups. These amplified bands were used to generate molecular phenograms inside theSecale genus.  相似文献   

9.
The Alcidae is a unique assemblage of Northern Hemisphere seabirds that forage by "flying" underwater. Despite obvious affinities among the species, their evolutionary relationships are unclear. We analyzed nucleotide sequences of 1,045 base pairs of the mitochondrial cytochrome b gene and allelic profiles for 37 allozyme loci in all 22 extant species. Trees were constructed on independent and combined data sets using maximum parsimony and distance methods that correct for superimposed changes. Alternative methods of analysis produced only minor differences in relationships that were supported strongly by bootstrapping or standard error tests. Combining sequence and allozyme data into a single analysis provided the greatest number of relationships receiving strong support. Addition of published morphological and ecological data did not improve support for any additional relationship. All analyses grouped species into six distinct lineages: (1) the dovekie (Alle alle) and auks, (2) guillemots, (3) brachyramphine murrelets, (4) synthliboramphine murrelets, (5) true auklets, and (6) the rhinoceros auklet (Cerorhinca monocerata) and puffins. The two murres (genus Uria) were sister taxa, and the black guillemot (Cepphus grylle) was basal to the other guillemots. The Asian subspecies of the marbled murrelet (Brachyramphus marmoratus perdix) was the most divergent brachyramphine murrelet, and two distinct lineages occurred within the synthliboramphine murrelets. Cassin's auklet (Ptychoramphus aleuticus) and the rhinoceros auklet were basal to the other auklets and puffins, respectively, and the Atlantic (Fratercula arctica) and horned (Fratercula corniculata) puffins were sister taxa. Several relationships among tribes, among the dovekie and auks, and among the auklets could not be resolved but resembled "star" phylogenies indicative of adaptive radiations at different depths within the trees.   相似文献   

10.
Four plastid markers, four nuclear markers and 14 morphometric characters were used in this study to investigate the evolution of Dactylorhiza baltica (Orchidaceae) in European Russia. In total, 98, 214 and 775 samples from 85, 112 and 121 populations were involved in the combined and separate molecular and morphometric analyses, respectively. In most cases, morphometric measures were done on exactly the same plants that were used for DNA studies. Dactylorhiza baltica plants from European Russia are most probably the products of several recent and mostly local hybridization events between the diploids D. fuchsii and D. incarnata , which have each been the maternal parent on different occasions. Considerable introgression into the parental diploids via the allopolyploid D. baltica is also hypothesized. Several morphological characters, such as length of the lip lateral lobe and the length of longest leaf, were found to be robust and could be useful in identification of D. baltica . This study demonstrates the advantage of 'combined' techniques, especially in the case of taxonomically complex taxa.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 257–274.  相似文献   

11.
对采自芜湖市三个不同水体中的萼花臂尾轮虫(Brachionus calyciflorus)17个克隆的线粒体COⅠ基因和rDNAITS1序列进行的分析结果表明:萼花臂尾轮虫不同克隆间COⅠ基因序列差异百分比为0-14.0%,平均为5.1%;ITS1序列差异百分比为0-7.4%,平均为2.2%。基于COⅠ基因序列构建的分子系统树(NJ树、MP树、ML树和贝叶斯树)均支持将17个克隆划分为三个姐妹种,各姐妹种间的序列差异百分比为7.2%-14.0%。基于ITS1序列构建的同样四种分子系统树也支持将17个克隆划分为三个姐妹种,但其中的克隆HE5在姐妹种中的归属与基于COⅠ基因序列构建的分子系统树所得出的结果不同,各姐妹种间的序列差异百分比为1.9%-7.4%。混交雌体和雄体间的交配实验结果表明,轮虫各姐妹种间存在着明显的生殖隔离,克隆HE5在姐妹种中的归属应与基于COⅠ基因序列构建的分子系统树所得出的结果一致;ITS1序列进化速率较低,不宜用于轮虫姐妹种的准确甄别。COⅠ基因进化钟计算结果显示,三个姐妹种间,克隆LE9所属的姐妹种早在8百万年前便分化形成出来,HE1、HE2、HE4-7所属的姐妹种于5百万年前分化产生。  相似文献   

12.
13.
Onychophoran sperm share striking apomorphies with sperm of oligcchaetes: the elongate, cylindrical, strongly condensed nucleus with (enchytraeid oligochaetes only) spiral keel(s); interpolation of mitochondria, which are spiral as in some microdriles, between nucleus and axoneme (autapomorphy); presence of postmitochondrial annulus; occurrence of a basal cylinder at the anterior end of the two central singlets (autapomorphy). Onychophoran sperm differ notably from oligochaete sperm: in possessing periacrosomal material; in the helical coiling, reduction, or absence of the acrosome vesicle (though acrosomal coiling occurs in leeches); in the conical subacrosomal structure contrasting with the characteristic acrosome tube of euclitellates; in the absence of a perforatorium (though these two features could be consequent on the reduction of the acrosome); in lacking a distinct padlike thickening of the anterior nuclear envelope; in possessing (external to the mutual 9 + 2 axoneme) 9 peripheral singlets and a subplasmalemmal microtubular manchette (also present in questid annelids); and in the scattered, rather than regularly arranged, peripheral glycogen of the axoneme; they also lack two additional fibres which give the characteristic tetragon of the oligochaete axoneme; and, although the centriolar triplets are disrupted, having a more complete distal centriole than in euclitellates. The remarkable similarities to euclitellate sperm, coupled with embryological similarities between Onychophora and Euclitellata, suggest that the onychophoran-euclitellate assemblage is a monophyletic group and the sister-group of the myriapod-hexapod assemblage. Wider phylogenetic implications of these findings are discussed.  相似文献   

14.
The Pterygiella complex, i.e. Pterygiella, Phtheirospermum, Pseudobartsia and Xizangia, is controversial in terms of both its relationships and taxonomic status. The genera of the complex are all species‐poor and endemic to eastern Asia. In this study, we sampled all taxa in the complex for seven genic regions [atpB‐rbcL, atpH‐I, psbA‐trnH, rpl16 intron, trnL‐F, trnS‐G and internal transcribed spacer (ITS)], which were analysed separately and in combination. We examined capsule and seed morphology of these genera using scanning electron microscopy (SEM). Our results indicate that the complex is polyphyletic and comprises two clades. The first, designated ‘Pterygiella complex I’, includes only Phtheirospermum japonicum. This clade is uniquely diagnosed by its papery yellow capsule and reticulate secondary thickening on the seed coat. The second clade, ‘Pterygiella complex II’, includes Phtheirospermum tenuisectum, P. parishii, P. muliense, Pseudobartsia, Xizangia and Pterygiella. These taxa share a coriaceous capsule. Pterygiella is monophyletic and is characterized by eglandular, unicellular, pilose hairs on the capsule and hook‐like protuberances on the horizontal ridges of the striate or reticulate seed coat. Excluding P. japonicum, the remaining taxa of Phtheirospermum cluster together and are sister to Pterygiella. Xizangia bartschioides and Pseudobartsia yunnanensis are separated from Pterygiella and Phtheirospermum, respectively, and are supported as genera by molecular and morphological evidence. © 2013 The Linnean Society of London  相似文献   

15.
Eight names in five genera Delphinium (Ranunculaceae), Lindernia and Mimulicalyx (Scrophulariaceae), Sorbus and Spiraea (Rosaceae) from China were not validly published because two gatherings were simultaneously designated as types in the protologues, or were simultaneously cited, without indicating the type in the protologues. These eight names are validated here, with one specimen designated as the holotype.  相似文献   

16.
To facilitate marker selection in sequence-based studies on genetic diversity and symbiont selectivity in lichens we conducted a comparison of eight molecular markers in the lichen-forming fungus Lasallia pustulata and its trebouxioid photobiont. We compared mtSSU rDNA, mtLSU rDNA, MCM7, TSR1 (mycobiont) and nrITS rDNA, COX2, psbJ-L intergenic spacer, rbcL (photobiont) of 45 individuals from European populations of L. pustulata. Mycobiont and photobiont loci had congruent phylogenetic signals. Based on the results of this study we recommend the use of MCM7 and TSR1 (mycobiont), and nrITS rDNA and COX2 (photobiont). In this specific study system we found no sequence variability in the mycobiont loci EF1, nrITS rDNA, RPB1, and RPB2, which we sequenced for a subset of individuals. We had limited success amplifying GPD (mycobiont), actin and chloroplast LSU rDNA (photobiont), however, we do not rule out that these loci could be valuable markers in other species.  相似文献   

17.
In these postgenomic times where aspects of functional genetics and character evolution form a focal point of human-mouse comparative research, primate phylogenetic research gained a widespread interest in evolutionary biology. Nevertheless, it also remains a controversial subject. Despite the surge in available primate sequences and corresponding phylogenetic interpretations, primate origins as well as several branching events in primate divergence are far from settled. The analysis of SINEs - short interspersed elements - as molecular cladistic markers represents a particularly interesting complement to sequence data. The following summarizes and discusses potential applications of this new approach in molecular phylogeny and outlines main results obtained with SINEs in the context of primate evolutionary research. Another molecular cladistic marker linking the tarsier with the anthropoid primates is also presented. This eliminates any possibility of confounding phylogenetic interpretations through lineage sorting phenomena and makes use of a new point of view in settling the phylogenetic relationships of the primate infraorders.  相似文献   

18.
Relationships among the five groups of extant seed plants (cycads, Ginkgo, conifers, Gnetales, and angiosperms) remain uncertain. To explore relationships among groups of extant seed plants further and to attempt to explain the conflict among molecular data sets, we assembled a data set of four plastid (cpDNA) genes (rbcL, atpB, psaA, and psbB), three mitochondrial (mtDNA) genes (mtSSU, coxI, and atpA), and one nuclear gene (18S rDNA) for 19 exemplars representing the five groups of living seed plants. Analyses of the combined eight-gene data set (15?772 base pairs/taxon) with maximum parsimony (MP), maximum likelihood (ML), and Bayesian approaches reveal a gymnosperm clade that is sister to angiosperms. Within the gymnosperms, a conifer clade includes Gnetales as sister to Pinaceae. Cycads and Ginkgo are either successive sisters to this conifer clade (including Gnetales) or a clade that is sister to conifers and Gnetales. All analyses of the mtDNA partition and ML analyses of the nuclear partition yield very similar topologies. However, MP analyses of the combined cpDNA genes place Gnetales as sister to all other seed plants with strong bootstrap support, whereas ML and Bayesian analyses of the cpDNA data set place Gnetales as sister to Pinaceae. Maximum parsimony and ML analyses of first and second codon positions of the cpDNA partiation also place Gnetales as sister to Pinaceae. In contrast, MP analyses of third codon positions place Gnetales as sister to other seed plants, although ML analyses of third codon positions place Gnetales with Pinaceae. Thus, most of the discrepancies in seed plant topologies involve third codon positions of cpDNA genes. The likelihood ratio (LR) and Shimodaira-Hasegasa (SH) tests were applied to the cpDNA data. The preferred topology based on the LR test is that Gnetales are sister to Pseudotsuga. The SH test based on first and second codon and all three codon positions indicated that there is no significant difference between the best topology (Gnetales sister to Pseudotsuga) and Gnetales sister to a conifer clade. However, there is a significant difference between the best topology and topologies in which Gnetales are sister to the rest of the seed plants or Gnetales sister to angiosperms.  相似文献   

19.
Genetic techniques are providing tools that are necessary to answer questions concerning the ecology and evolution of cnidarians that, until recently, could not be easily addressed. In developing molecular markers for cnidarians with algal symbionts (zooxanthellae), however, caution must be used to ensure the markers in question are derived from the cnidarian host and not zooxanthellae. Unless the DNA template is from asymbiotic tissue, both host and symbiont genomes are present in the DNA template and zooxanthella-specific markers are often inadvertently generated. Steps should be taken to minimize the contamination by zooxanthella DNA in the template, and the origin of the molecular marker (host or symbiont) must be verified. Including zooxanthella-specific markers in analyses for cnidarians will confound interpretations of the results as biogeographic and phylogeographic patterns of zooxanthellae do not necessarily reflect those of the host.  相似文献   

20.
Abstract

Identifying germplasm is an important component for efficient and effective management of plant genetic resources. This investigation was undertaken for the identification and analysis of genetic variation within 9 species of Albizzia through 33 morphological parameters, and 15 Random Amplified Polymorphic DNA (RAPD) and 17 Inter Simple Sequence Repeat (ISSR) primers. The use of selected RAPD and ISSR primers generated a total of 163 and 201 amplified DNA fragments, respectively. High frequencies of polymorphism, 95.05% for RAPD and 96.02% for ISSR, were detected. Statistical approaches were employed to construct genetic relationships by RAPD, ISSR and morphological analysis. Cluster analysis by the unweighted pair-group method (UPGMA) of Nei's similarity generated dendograms with similar topology that gave a better reflection of the diversity and affinities between species. These molecular results were comparable to main morphological characteristics. The correlation matrices generated by RAPD and ISSR markers were highly correlated (r = 0.843 at p = 1.0), thereby indicating congruence between these two marker systems. Both morphometric data and molecular markers have the potential to analyse genetic variation among the nine species of Albizzia, thus providing a major input for management strategy of plant genetic resources.  相似文献   

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