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1.
The medicinal plants from the genus Coptis were widely applied in clinical treatment, but no stable and systemic methods have been established for species identification and quality evaluation. Although several analytical methods have been reported for the detection of alkaloids, so far no attempt has been made to analyze the interspecific relationships between molecular phylogeny and main alkaloids in Coptis. In this study, the phylogenetic relationships within the genus Coptis from China are resolved with high support. Coptis chinensis, Coptis deltoidea and Coptis omeiensis cluster together, and this clade (‘clade III’) is sister to Coptis teeta. Here, we provide evidences that the relationships inferred by chemical taxonomy are different to those of the present molecular phylogeny. Within clade III, C. deltoidea, C. omeiensis and C. chinensis are sister to C. teeta, while C. teeta shares more similar metabolic compounds with C. deltoidea, and C. omeiensis than with C. chinensis. Most likely, the metabolic components are mainly affected by environmental factors resulting in convergent evolution of alkaloid contents that do not reflect phylogenetic relationships.  相似文献   

2.
Previous morphological analysis has indicated that subgenus Meconostigma was the basal group of the genus and sister group of a clade formed by subgenera Philodendron and Pteromischum. However, recent molecular analysis suggests Pteromischum is the sister group of the clade Philodendron and Meconostigma. The objective of this work was to anatomically describe the stem of Philodendron, searching for possible synapomorphies for the three currently accepted subgenera, and thus give support to one of the two phylogenetic hypotheses, and to contribute new and updated information about characters relevant to the taxonomy of the group. Anatomical data were obtained from 14 species of Philodendron. The main conclusions of our study were recognition of a sclerified hypodermis and storied cork in Philodendron and verification of the absence of amphivasal bundles, the presence of which was previously suggested for the genus by French and Tomlinson. The presence of a branched root vascular plexus in Meconostigma and Philodendron gives support to the phylogenetic hypothesis in which those two subgenera form a monophyletic clade. The unistratified and sclerified hypodermis, only simple vascular bundles within the periphery of the central cylinder, and a connection through a fibrous sheath between them were considered apomorphic characters of Pteromischum.  相似文献   

3.
Molecular phylogenies often reveal that taxa circumscribed by phenotypical characters are not monophyletic. While re-examination of phenotypical characters often identifies the presence of characters characterizing clades, there is a growing number of studies that fail to identify diagnostic characters, especially in organismal groups lacking complex morphologies. Taxonomists then can either merge the groups or split taxa into smaller entities. Due to the nature of binomial nomenclature, this decision is of special importance at the generic level. Here we propose a new approach to choose among classification alternatives using a combination of morphology-based phylogenetic binning and a multiresponse permutation procedure to test for morphological differences among clades. We illustrate the use of this method in the tribe Thelotremateae focusing on the genus Chapsa, a group of lichenized fungi in which our phylogenetic estimate is in conflict with traditional classification and the morphological and chemical characters do not show a clear phylogenetic pattern. We generated 75 new DNA sequences of mitochondrial SSU rDNA, nuclear LSU rDNA and the protein-coding RPB2. This data set was used to infer phylogenetic estimates using maximum likelihood and Bayesian approaches. The genus Chapsa was found to be polyphyletic, forming four well-supported clades, three of which clustering into one unsupported clade, and the other, supported clade forming two supported subclades. While these clades cannot be readily separated morphologically, the combined binning/multiresponse permutation procedure showed that accepting the four clades as different genera each reflects the phenotypical pattern significantly better than accepting two genera (or five genera if splitting the first clade). Another species within the Thelotremateae, Thelotrema petractoides, a unique taxon with carbonized excipulum resembling Schizotrema, was shown to fall outside Thelotrema. Consequently, the new genera Astrochapsa, Crutarndina, Pseudochapsa, and Pseudotopeliopsis are described here and 39 new combinations are proposed.  相似文献   

4.
Free amino acids are important bioactive ingredients in herbs and herbal products. Coptis herbs contain a variety of free amino acids; however, studies have not yet analyzed the relationship between free amino acids and species of Coptis herbs. In the current study, the contents of 20 free amino acids in Coptis chinensis Franch., Coptis teeta Wall., and Coptis deltoidea C.Y. Cheng et Hsiao were determined using an automatic amino acid analyzer to evaluate the differences between the three species. We found that the major amino acids (Asn, Arg, and γ-aminobutyric acid (GABA)) were significantly more in C. chinensis than in the other two species. In addition, Asp content was significantly more in C. deltoidea. The study concluded that Asn can be used to identify C. deltoidea, C. chinensis, and C. teeta, and Gln and Arg can be used to distinguish C. teeta from C. chinensis and C. deltoidea. These findings suggested that free amino acids as active ingredients can be used to identify Coptis herb species.  相似文献   

5.
A phylogeny of the genus Aphis Linnaeus, 1 758 was built primarily from specimens collected in the Midwest of the United States. A data matrix was constructed with 68 species and 41 morphological characters with respective character states of alate and apterous viviparous females. Dendrogram topologies of analyses performed using UPGMA (Unweighted Pair Group Method with Arithmetic Mean), Maximum Parsimony and Bayesian analysis of Cytochrome Oxidase I, Elongation Factor 1‐α and primary endosymbiont Buchnera aphidicola 16S sequences were not congruent. Bayesian analysis strongly supported most terminal nodes of the phylogenetic trees. The phylogeny was strongly supported by EF1‐α, and analysis of COI and EF1‐α molecular data combined with morphological characters. It was not supported by single analysis of COI or Buchnera aphidicola 16S. Results from the Bayesian phylogeny show 4 main species groups: asclepiadis, fabae, gossypii, and middletonii. Results place Aphis and species of the genera Protaphis Börner, 1952, Toxoptera Koch, 1856 and Xerobion Nevsky, 1928 in a monophyletic clade. Morphological characters support this monophyly as well. The phylogeny shows that the monophyletic clade of the North American middletonii species group belong to the genus Protaphis: P. debilicornis (Gillette & Palmer, 1929 ), comb. nov., P. echinaceae (Lagos and Voegtlin, 2009 ), comb. nov., and P. middletonii (Thomas, 1879 ). The genus Toxoptera should be considered a subgenus of Aphis (stat. nov.). The analysis also indicates that the current genus Iowana Frison, 1954 should be considered a subgenus of Aphis (stat. nov.).  相似文献   

6.
Cyathocline, a small genus, has been treated as a member of subtribe Grangeinae of tribe Astereae (Asteraceae), but has been neglected in molecular phylogenetic analyses of Astereae. Plastid trnL-F and nuclear ribosomal DNA ITS sequences were used to carry out phylogenetic analyses of Cyathocline (represented by C. purpurea) through maximum parsimony and Bayesian analyses. In addition, its karyotype, morphology and micromorphology were also investigated. The results show that in our three phylogenetic trees, C. purpurea is deeply nested within the Blumea clade and/or the Inulinae clade, and is closest to Blumea balsamifera (Inuleae, Inulinae). C. purpurea is similar to Blumea in chromosome size bimodality and to Inulinae in one single large oxalate crystal within each cell of the cypsela epidermis, which, together with molecular evidences, suggests strongly that Cyathocline should be transferred from Astereae to Inuleae subtribe Inulinae. Although C. purpurea has many anomalous features, its most characters still are within a wide range of morphological variations of Blumea. DNA data and the karyotypic character support to merge C. purpurea into Blumea. As a result, the new combination Blumea purpurea (O. Kuntze) W.P. Li was made.  相似文献   

7.
It has been suggested that gene duplication and polyploidization create opportunities for the evolution of novel characters. However, the connections between the effects of polyploidization and morphological novelties have rarely been examined. In this study, we investigated whether petal pigmentation patterning in an allotetraploid Clarkia gracilis has evolved as a result of polyploidization. Clarkia gracilis is thought to be derived through a recent polyploidization event with two diploid species, C. amoena huntiana and an extinct species that is closely related to C. lassenensis. We reconstructed phylogenetic relationships of the R2R3-MYBs (the regulators of petal pigmentation) from two subspecies of C. gracilis and the two purported progenitors, C. a. huntiana and C. lassenensis. The gene tree reveals that these R2R3-MYB genes have arisen through duplications that occurred before the divergence of the two progenitor species, that is, before polyploidization. After polyploidization and subsequent gene loss, only one of the two orthologous copies inherited from the progenitors was retained in the polyploid, turning it to diploid inheritance. We examined evolutionary changes in these R2R3-MYBs and in their expression, which reveals that the changes affecting patterning (including expression domain contraction, loss-of-function mutation, cis-regulatory mutation) occurred after polyploidization within the C. gracilis lineages. Our results thus suggest that polyploidization itself is not necessary in producing novel petal color patterns. By contrast, duplications of R2R3-MYB genes in the common ancestor of the two progenitors have apparently facilitated diversification of petal pigmentation patterns.  相似文献   

8.
A comprehensive study based on gland and seed micromorphology in Euphorbia (Euphorbiaceae) for species distributed in Iranian highlands is presented. A total of 86 species were studied. The gland structure was examined by direct field observations. Taxonomically important characters of glands were observed and measured: size, texture, shape, color, and horns. For species out of Iran herbarium materials were studied. Seed characteristics were examined using scanning electron microscopy (SEM) as well as dissecting light microscopy. Significant features are: seed size, seed shape, presence of caruncle, shape of caruncle, and seed surface ornamentation. A phylogenetic study using Maximum Parsimony (MP) and Bayesian Inference (BI) was performed based on sequences of nuclear DNA internal transcribed spacers (ITS) for selected species representing the main clades known in Euphorbia and with special focus on the species distributed in Iranian highlands. ITS sequences for 20 accessions representing 19 species are provided for the first time, and 48 accessions of 47 species were used from GenBank. The topologies of both analyses were congruent. The results indicate: (1) four main clades with high supports in subgen. Esula which are appropriate to be recognized at sectional rank. (2) E. larica is nested within clade A including few members of subgen. Rhizanthium and is closely related to sect. Balsamis, which is suggested here to be transferred from subgen. Esula into subgen. Rhizanthium. (3) E. osyridea of the monotypic subsect. Osyrideae is closely related to E. buhsei and to the members of sect. Esula. Tracing morphological characters on the phylogenetic tree shows that several morphological characters, such as seed ornamentation applied in previous subgeneric classification of the subgen. Esula, are homoplasious, but the gland structure and capsule surface characters are more reliable for classification purposes.  相似文献   

9.
Floral initiation and development of Hedysarum varium, Onobrychis melanotricha and Alhagi persarum was studied using epi-illumination light-microscopy techniques. The studied species belong to the tribe Hedysareae of the inverted repeat loss clade (IRLC clade), which is characterized by missing the large inverted repeat in the chloroplast genome. The main aim of our study was to determine developmental bases for similarities and differences among the three taxa and to verify the position of Alhagi relative to other genera of the IRLC clade. According to our observations, bracteoles are missing in Onobrychis melanotricha, but are present in the other two species. All three species share unidirectional sepal initiation starting with a median abaxial sepal and bidirectional petal initiation. Stamen initiation is unidirectional in all except in the outer stamen whorl of Hedysarum varium, where it is bidirectional. An important ontogenetic feature in O. melanotricha is the existence of five common primordia, which give rise to petal and stamen primordia. Although in H. varium and O. melanotricha common primordia are observed at some stages in floral organ initiations, in Alhagi all organs are initiated separately. Moreover, overlap in time of floral organs initiation occurs in H. varium and O. melanotricha, but not in A. persarum. The carpel initiates concurrently with the petal primordia in all. It might be presumed that Alhagi is primitive in relation to the other studied Hedysareae taxa, due to the presence of bracteoles, the absence of common primordia, and the lack of overlap in time of different organ initiations.  相似文献   

10.
We performed molecular phylogenetic analyses of four morphotypes of the benthic foraminiferal genus Bulimina (B. aculeata, B. marginata f. marginata, B. marginata f. denudata, and B. elongata) based on sequences of internal transcribed spacer region of ribosomal DNA (ITS rDNA). Six genetically distinct phylotypes were revealed by our phylogenetic analyses. The six phylotypes basically correspond to the fundamental morphotypes: clades A + B (B. aculeata); clade C (B. elongata); clade D (B. marginata f. denudata); clade E (B. marginata f. marginata genotype 1); and clade F (B. marginata f. marginata genotype 2). All six phylotypes are well distinguished, except phylotype B, which shows only little sequence divergence compared to clade A, possibly indicating that genetic differentiation is in progress. Morphological characters including the direction, placement, and shape of spines, the angle of undercutting of chamber periphery, and the roundness of the chambers were stable among specimens of each clade. In contrast, the length and density of spines, and chamber size, were variable within each clade. These intermediate morphological characters may reflect ecophenotypic variation. Our study clearly shows that the examined B. acuelata, elongata, and denudata morphospecies are genetically separated and that B. marginata is a species complex comprising several genotypes. A novel phylotype represent different morphotype compare to B. marginata f. marginata that can be distinguished based on differences of chamber angularity, the direction, placement, and shape of spines, and test dimensions.  相似文献   

11.
A new poroid wood-inhabiting fungal species, Ceriporiopsis kunmingensis sp. nov., is proposed based on morphological and molecular characters. The species is characterized by resupinate basidiocarps with pale cinnamon-buff to ochreous color when dry; generative hyphae unbranched and subparallel along the tubes; presence of hyphal ends; allantoid basidiospores, 4.5–5 × 1.5–2 μm. The internal transcribed spacer (ITS) and large subunit (LSU) regions of nuclear ribosomal RNA gene sequences of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony, and Bayesian inference methods. The phylogenetic analysis based on molecular data of ITS?+?nLSU sequences showed that C. kunmingensis belonged to the phlebioid clade, formed a monophyletic lineage with a strong support (100% BS, 100% BP, 1.00 BPP), and was closely related to Phlebia aurea, and then grouped with P. livida and P. subserialis. Both morphological and molecular characters confirmed the placement of the new species in Ceriporiopsis.  相似文献   

12.
13.
14.
Impatiens L. is one of the largest angiosperm genera, containing over 1000 species, and is notorious for its taxonomic difficulty. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the genus to date based on a total evidence approach. Forty‐six morphological characters, mainly obtained from our own investigations, are combined with sequence data from three genetic regions, including nuclear ribosomal ITS and plastid atpB‐rbcL and trnL‐F. We include 150 Impatiens species representing all clades recovered by previous phylogenetic analyses as well as three outgroups. Maximum‐parsimony and Bayesian inference methods were used to infer phylogenetic relationships. Our analyses concur with previous studies, but in most cases provide stronger support. Impatiens splits into two major clades. For the first time, we report that species with three‐colpate pollen and four carpels form a monophyletic group (clade I). Within clade II, seven well‐supported subclades are recognized. Within this phylogenetic framework, character evolution is reconstructed, and diagnostic morphological characters for different clades and subclades are identified and discussed. Based on both morphological and molecular evidence, a new classification outline is presented, in which Impatiens is divided into two subgenera, subgen. Clavicarpa and subgen. Impatiens; the latter is further subdivided into seven sections.  相似文献   

15.
16.

Background and Aims

The subgenus Ceratotropis in the genus Vigna is widely distributed from the Himalayan highlands to South, Southeast and East Asia. However, the interspecific and geographical relationships of its members are poorly understood. This study investigates the phylogeny and biogeography of the subgenus Ceratotropis using chloroplast DNA sequence data.

Methods

Sequence data from four intergenic spacer regions (petA-psbJ, psbD-trnT, trnT-trnE and trnT-trnL) of chloroplast DNA, alone and in combination, were analysed using Bayesian and parsimony methods. Divergence times for major clades were estimated with penalized likelihood. Character evolution was examined by means of parsimony optimization and MacClade.

Key Results

Parsimony and Bayesian phylogenetic analyses on the combined data demonstrated well-resolved species relationships in which 18 Vigna species were divided into two major geographical clades: the East Asia–Southeast Asian clade and the Indian subcontinent clade. Within these two clades, three well-supported eco-geographical groups, temperate and subtropical (the East Asia–Southeast Asian clade) and tropical (the Indian subcontinent clade), are recognized. The temperate group consists of V. minima, V. nepalensis and V. angularis. The subtropical group comprises the V. nakashimaeV. riukiuensisV. minima subgroup and the V. hirtellaV. exilisV. umbellata subgroup. The tropical group contains two subgroups: the V. trinerviaV. reflexo-pilosaV. trilobata subgroup and the V. mungoV. grandiflora subgroup. An evolutionary rate analysis estimated the divergence time between the East Asia–Southeast Asia clade and the Indian subcontinent clade as 3·62 ± 0·3 million years, and that between the temperate and subtropical groups as 2·0 ± 0·2 million years.

Conclusions

The findings provide an improved understanding of the interspecific relationships, and ecological and geographical phylogenetic structure of the subgenus Ceratotropis. The quaternary diversification of the subgenus Ceratotropis implicates its geographical dispersal in the south-eastern part of Asia involving adaptation to climatic condition after the collision of the Indian subcontinent with the Asian plate. The phylogenetic results indicate that the epigeal germination is plesiomorphic, and the germination type evolved independently multiple times in this subgenus, implying its limited taxonomic utility.  相似文献   

17.
Previous phylogenetic analyses of Ranunculales, which have mostly been focused on an individual family and were based on molecular data alone, have recovered three main clades within the order. However, support for relationships among these three clades was weak. Earlier hypotheses were often hampered by limited taxon sampling; to date less than one-tenth of the genera in the order have been sampled. In this study, we used a greatly enlarged taxon sampling (105 species, representing 99 genera of all seven families in the order). Our study is, furthermore, the first to employ morphology (65 characters) in combination with sequence data from four genomic regions, including plastid rbcL, matK and trnL-F, and nuclear ribosomal 26S rDNA to reconstruct phylogenetic relationships within Ranunculales. Maximum parsimony and Bayesian inference were performed on the individual and combined data sets. Our analyses concur with those of previous studies, but in most cases provide stronger support and better resolution for relationships among the three main clades retrieved. The first, comprised solely of the monogeneric family Eupteleaceae, is the earliest-diverging lineage. The second clade is composed exclusively of taxa of Papaveraceae, which is sister to the third clade, the core Ranunculales, comprising the other five families of the order. Circaeasteraceae and Lardizabalaceae form a strongly supported clade. Pteridophyllum is supported as sister to Hypecoum, contradicting the viewpoint that the former is the earliest-diverging genus in Papaveraceae. Glaucidium is basalmost in Ranunculaceae. Within this phylogenetic framework, the evolution of selected characters is inferred and diagnostic morphological characters at different taxonomic levels are identified and discussed. Based on both morphological and molecular evidence, a classification outline for Ranunculales is presented, including the proposal of two new subfamilies, Menispermoideae and Tinosporoideae in Menispermaceae and a new tribe, Callianthemeae, for the genus Callianthemum (Ranunculaceae).  相似文献   

18.

Background and Aims

Preservation of cultivar purity creates a particular challenge for plants that are self-incompatible, require insects for cross-pollination, and have easily germinating seeds and vigorously spreading rhizomes. As the fields must be planted with mixed populations, and a balance must be maintained between the cultivars to achieve effective pollination, methods for field monitoring of the relative density of different cultivars must be practical. Furthermore, a DNA-based method is needed for cultivar verification in the collections and outside of the growing season. The aim of this study was to develop both types of methods for Rubus arcticus (arctic bramble).

Methods

Morphological parameters were measured from six cultivars grown on three farms. Observations from the flowers and fruits included: petal and sepal number, flower diameter, arrangement of petals, size of calyx in relation to corolla, fruit weight, yield and soluble sugars. Observations from the leaves included: width and height of middle leaflet, shape of the base of terminal leaflet, shape of terminal leaflet, leaf margin serration and fingertip touch. The applicability of simple sequence repeat (SSR) or microsatellite DNA markers developed for red raspberry was tested on eight arctic bramble cultivars.

Key Results and Conclusions

Morphological and molecular identification methods were developed for R. arcticus. The best morphological characteristics were the length-to-width ratio of the middle leaflet and leaf margin serration. A particular characteristic, fingertip touch, was shown by electron microscopy to be related to the density and quality of the leaf hairs. Red raspberry SSR marker no. 126 proved to be applicable for differentiation of the eight arctic bramble cultivars tested. These identification methods are critical to secure the maintenance and management of R. arcticus. However, the challenges faced and approaches taken are equally applicable to other species with similar biology.  相似文献   

19.
Alternanthera (Amaranthaceae) is a diverse genus (80–200 species) largely restricted to the American Tropics. With Pedersenia and Tidestromia, it makes up the ‘Alternantheroid clade’ in Gomphrenoideae. Parsimony and Bayesian analyses of nucleotide sequences of nuclear (ITS) and plastid (rpl16, trnL‐F) and morphological characters identify that the capitate stigma of Alternanthera is a synapomorpy within the Alternantheroids. Within Alternanthera, two major clades were resolved, both of which were marked by otherwise homoplasious characters of the gynoecium: Clade A [99% jackknife (JK); 1.0 posterior probability (PP)] with nine species and Clade B (60% JK; 0.98 PP) with 22 species. Four subclades (B1–B4), strongly supported statistically, were identified in Clade B. Previous subgeneric classifications of Alternanthera appear artificial in light of our new molecular phylogenetic analyses. Most major lineages are congruently resolved by nuclear and plastid data but some incongruence between the nrITS and plastid phylogenetic trees suggests hybridization may have played a role in the rampant speciation in Alternanthera. Whereas C4 photosynthesis appears to have evolved in a single clade, the position of A. littoralis var. maritima (C3) in this clade may be explained by hybrid speciation rather than a reversal from C4 to C3. All C3–C4 intermediates belong to a different clade that also contains C3 species, but species limits, including the widely studied A. tenella, are unclear. The clade including A. tenella and A. halimifolia contains most of the species endemic to the Galápagos whereas A. nesiotes, also endemic to the islands, is nested among widespread American taxa. This suggests that the Galápagos radiation of Alternanthera may have arisen from at least two independent colonization events followed by a subsequent radiation in the former lineage. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169 , 493–517.  相似文献   

20.
Systematics of the genus Isatis (Brassicaceae) is difficult and controversial, and previous studies were based solely on morphological characters. Sequence variation of the internal transcribed spacer (ITS) regions and the 5.8S gene of nuclear ribosomal DNA (nrDNA) were analyzed using parsimony and Bayesian methods. Twenty-eight taxa of Isatis and related genera of the tribe Isatideae were sampled, including 20 Isatis species representing almost all major morphological lineages, all three species of Pachypterygium, two of nine species of Sameraria, and monospecific Boreava, Myagrum, and Tauscheria. Two well-supported clades were resolved in the ITS tree, and they demonstrate the artificiality of the present delimitation of the tribe. One clade includes I. emarginata, I. minima, I. trachycarpa, P. brevipes, P. multicaule, P. stocksii, and T. lasiocarpa. The second clade includes I. buschiana, the polymorphic I. cappadocica with five subspecies, I. gaubae, I. kotschyana, I. leuconeura, I. pachycarpa, I. takhtajanii, I. tinctoria, and S. armena. Pachypterygium is polyphyletic and, together with Boreava, Sameraria, and Tauscheria, all are nested within Isatis. This study is a continuation of our recent systematic survey based on seed-coat microsculpturing ( Moazzeni et al., 2007. Flora 202, 447–454) and reveals that fruit characters mapped onto the molecular tree show considerable convergence. The reliance on fruit characters alone in the delimitation of genera may well lead to erroneous phylogenetic results and thus to incorrect taxonomic conclusions.  相似文献   

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