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Sequence variability of the ITS spacers and 5.8S rRNA gene was examined in 11 accessions of the subfamily Scilloideae, including seven accessions of rare and endangered species Bellevalia sarmatica from Volgograd region. The intraspecific polymorphism level of the examined ITS1–5.8S–ITS2 sequence of B. sarmatica accessions constituted 1.3%. The phylogenetic position of B. sarmatica within the genus Bellevalia was determined. It was demonstrated that B. sarmatica belonged to the section Nutantes, and the most closely related species were B. webbiana and B. dubia. Nucleotide substitutions in the 5.8S rRNA gene sequence of the analyzed Scilloideae accessions were identified and studied. The predicted secondary structure of 5.8S rRNA gene was constructed. It was demonstrated that in the examined accessions, mutations in the 5.8S rRNA gene were mainly localized in the third hairpin region and had no effect on the secondary structure of the 5.8S rRNA molecule.  相似文献   

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Orostachys (Crassulaceae) is a small genus of succulent plants having a predominantly East Asian distribution. Recent DNA sequence comparisons revealed polyphyletic nature of the genus and found distant relationship between its infrageneric taxa. Here we present the first molecular phylogeny of Orostachys subsection Appendiculatae based on a large number of ITS rDNA sequences representing most currently recognized members of the subsection and utilizing secondary structure information. Ribosomal spacer was a highly informative marker and provided a phylogenetic signal sufficient to resolve relationships at different scales, from affinities between species to a fine geographic structure in broadly sampled species. It was also conservative enough to allow unambiguous alignment and construction of consensus secondary structure models for ITS1 and ITS2. These models displayed a number of molecular synapomorphies defining most lineages established in our analyses. We revealed a major split in the subsection placing three species, O. spinosa, O. japonica and O. chanetii, into a strongly supported clade to the exclusion of O. thyrsiflora. Phenotypically distinct monotypic genus Meterostachys was also resolved as a part of the subsection’s clade and showed affinity to O. thyrsiflora. Our data suggested that morphology-based species concept for O. thyrsiflora requires reassessment.  相似文献   

4.
The genus Tettigonia includes 26 species distributed in the Palaearctic region. Though the Green Bush-crickets are widespread in Europe and common in a variety of habitats throughout the Palaearctic ecozone, the genus is still in need of scientific attention due to the presence of a multitude of poorly explored taxa. In the present study, we sought to clarify the evolutionary relationships of Green Bush-crickets and the composition of taxa occurring in the Western Palaearctic. Based on populations from 24 disjunct localities, the phylogeny of the group was estimated using sequences of the cytochrome oxidase subunit I (COI) and the internal transcribed spacers 1 and 2 (ITS1 and ITS2). Morphological and acoustic variation documented for the examined populations and taxa was interpreted in the context of phylogenetic relationships inferred from our genetic analyses. The trees generated in the present study supported the existence of three main lineages: “A”—composed of all sampled populations of Tettigonia viridissima and the Tettigonia vaucheriana complex, “B”—comprising Tettigonia caudata, Tettigonia uvarovi, and the Tettigonia armeniaca complex, and “C”—consisting of Tettigonia cantans. The present study provides the first phylogenetic foundation for reviewing the systematics of Tettigonia (currently classified mostly according to morphological characteristics), proposing seven new synonymies.  相似文献   

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Orphanodendron is a taxonomically and geographically isolated South American genus of two species. When first described by Barneby and Grimes in 1990, the genus was placed in Leguminosae subfamily Caesalpinioideae, but that placement was doubted and the name Orphanodendron (Gr. orphanos, orphan + dendron, tree) was chosen to reflect the uncertain subfamilial relationship of the genus. In this study, nucleotide sequence data from five Orphanodendron specimens were added to 662 other, previously sampled, Leguminosae taxa representing all three currently recognized subfamilies (Caesalpinioideae, Mimosoideae and Papilionoideae) in a matK maximum parsimony analysis that resolved Orphanodendron as a member of the genistoid s.l. clade of subfamily Papilionoideae. Two additional Bayesian phylogenetic analyses with reduced taxon sampling of plastid (matK combined with trnL-F) and nuclear (ITS) loci strongly support the monophyly of Orphanodendron and unambiguously establish Orphanodendron as a member of the genistoid sensu lato clade. Although our plastid phylogenetic analysis finds relatively low support for a sister-group relationship with the African genus Camoensia, the nuclear-encoded ITS resolves Orphanodendron as sister to the Bowdichia clade with strong support and Camoensia as sister to other core genistoids. The phylogenetic resolution of Orphanodendron as a member of the genistoid s.l. legumes based on nuclear and plastid sequences will undoubtedly advance future evolutionary investigations of this Colombian endemic tropical tree genus.  相似文献   

6.
The genus Jatropha (Euphorbiaceae) contains species that are of significant economic and ornamental value. However, Jatropha breeding material is rather limited due to incomplete information regarding phylogenetic relationships among germplasm resources. Phylogenetic analyses were performed based on the internal transcribed spacer of nuclear ribosomal DNA (nrDNA ITS), two chloroplast regions (trnL-F and rbcL), and the combined (ITS+trnL-F+rbcL) dataset among twenty-five specimens representing six key Jatropha species. Phylogenetic relationships of Jatropha were well resolved between subgenus Curcas and subgenus Jatropha, and demonstrated the intermediate position of section Polymorphae among sections of both subgenera. Jatropha curcas and J. integerrima demonstrated a close phylogenetic relationship. The molecular data agreed with the morphological classification that recognized J. multifida and J. podagrica in sec. Peltatae. The distinct intraspecific divergence that occurred in J. curcas could be attributed to restricted gene flow caused by geographical isolation and different ecological conditions. Phylograms produced with trnL-F and rbcL sequence data suggested slow rates of sequence divergence among Jatropha spp., while the ITS gene tree had good resolution suggesting high genetic variation of ITS among Jatropha species.  相似文献   

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Two new species in the Fusarium solani species complex (FSSC) are described and introduced. The new taxa are represented by German isolates CBS 142481 and CBS 142480 collected from commercial yard waste compost and vascular tissue of a wilting branch of hibiscus, respectively. The phylogenetic relationships of the collected strains to one another and within the FSSC were evaluated based on DNA sequences of 6 gene loci. Due to the limited sequence data available for reference strains in GenBank, however, a multi-gene phylogenetic analysis included partial sequences for the internal transcribed spacer region and intervening 5.8S nrRNA gene (ITS), translation elongation factor 1-alpha (tef1) and the RNA polymerase II second largest subunit (rpb2). Morphological and molecular phylogenetic data independently showed that these strains are distinct populations of the FSSC, nested within Clade 3. Thus, we introduce Fusarium stercicola and Fusarium witzenhausenense as novel species in the complex. In addition, 19 plant species of 7 legume genera were evaluated for their potential to host the newly described taxa. Eighteen plant species were successfully colonized, with 6 and 9 of these being symptomatic hosts for F. stercicola and F. witzenhausenense, respectively. As plants of the family Fabaceae are very distant to the originally sourced material from which the new taxa were recovered, our results suggest that F. stercicola and F. witzenhausenense are not host-specific and are ecologically fit to sustain stable populations in variety of habitats.  相似文献   

9.
The possession of wings and ability to fly are a unifying character of higher insects, but secondary loss of wings is widespread. Within the bushcrickets, the subfamily Phaneropterinae (Orthoptera: Tettigonioidea) comprises more than 2000 predominantly long-winged species in the tropics. However, the roughly 300 European representatives are mainly short-winged. The systematics of these radiations have been unclear, leading to their unreliable formal treatment, which has hindered analysis of the evolutionary patterns of flight loss. A molecular phylogeny is presented for 42 short-winged species and members of all European long-winged genera based on the combined data from three nuclear gene sequences (18S, H3, ITS2). We found four phylogenetic lineages: (i) the first included the short-wing species of the genus Odontura; (ii) a further branch is represented by the South-American short-winged Cohnia andeana; (iii) an assemblage of long-wing taxa with a deep branching pattern includes the members of the tribes Acrometopini, Ducetiini, Phaneropterini, and Tylopsidini; (iv) a large group contained all short-winged taxa of the tribe Barbitistini. Phaneropterinae flightlessness originated twice in the Western Palaearctic, with a number of mainly allo- and parapatrically distributed species of the Barbistini in Southeastern Europe, and the Middle East and a limited number of Odontura species in Northern Africa and Southwestern Europe. Both short-winged lineages are well separated, which makes it necessary to restrict the tribe Odonturini to the West-Palaearctic genus Odontura. Other flightless genera previously included in the Odonturini are placed as incertae sedis until their phylogenetic position can be established.  相似文献   

10.
The plastid genome regions of two intergenic spacers, psbA–trnH and trnL–trnF, were sequenced to study the nucleotide diversity and phylogenetic relationships among Gladiolus cultivars. Nucleotide diversity of psbA–trnH region was higher than trnL–trnF region of chloroplast. We employed Bayesian, maximum parsimony (MP) and neighbour-joining (NJ) approaches for phylogenetic analysis of Gladiolus and related taxa using combined datasets from chloroplast genome. The psbA–trnH and trnL–trnF intergenic spacers of Gladiolus and related taxa-like Babiana, Chasmanthe, Crocus, Iris, Moraea, Sisyrinchium, Sparaxis and two out group species (Hymenocallis littoralis and Asphodeline lutea) were used in the present investigation. Results showed that subfamily Iridoideae have sister lineage with subfamily Ixioideae and Crocoideae. H. littoralis and A. lutea were separately attached at the base of tree as the diverging Iridaceae relative’s lineage. Present study revealed that psbA–trnH region are useful in addressing questions of phylogenetic relationships among the Gladiolus cultivars, as these intergenic spacers are more variable and have more phylogenetically informative sites than the trnL–trnF spacer, and therefore, are suitable for phylogenetic comparison on a lower taxonomic level. Gladiolus cultivars are extensively used as an ornamental crop and showed high potential in floriculture trade. Gladiolus cultivation still needs to generate new cultivars with stable phenotypes. Moreover, one of the most popular methods for generating new cultivars is hybridization. Hence, information on phylogenetic relationships among cultivars could be useful for hybridization programmes for further improvement of the crop.  相似文献   

11.
Limonium vulgare and related species form a complex group, but until now cytological and genetic studies have been based on single species and specific geographical areas. We investigated genome size, karyological and genetic diversity in samples from Western Mediterranean and evaluated the phylogenetic relationships among the species of this complex. Genome size was assessed using flow cytometry on samples from natural populations of L. vulgare, L. maritimum and L. narbonense. Chromosome counts were conducted in plants obtained from seeds collected in the field. The internal transcribed spacer ITS1 of the nuclear rDNAs was used to assess ITS polymorphisms as well as the phylogenetic relationships within the L. vulgare complex. Our analyses showed that all species were tetraploid, with the chromosome number of L. maritimum being presented here for the first time. Significant differences were observed in genome size, with L. narbonense having lower genome sizes than the other two species, and possible aneuploids being detected. Ten new ITS sequences from L. vulgare, L. narbonense and L. maritimum were provided. Most species’ populations showed unique ribotypes, and L. narbonense has the highest ribotype diversity. One of the L. maritimum populations presented a closer genetic relationship with L. vulgare, whereas the other two seemed to be more related with L. narbonense. Phylogenetic analyses confirmed that L. vulgare and L. narbonense form a monophyletic group, sister to the remaining Limonium species. Our results put into evidence that the studied species may represent a relatively early stage of divergence.  相似文献   

12.
Cortinarius is one of the most species-rich genera of mushroom-forming fungi. Based on phylogenetic and morphological evidence, Cortinarius, sect. Riederi, is introduced at sectional level (= subsect. Riederi sensu Brandrud & Melot). The taxonomy, phylogeny, ecology and distribution of not only mainly European but also including some North American taxa of this section are treated, which includes nine species and two varieties. Of these, three taxa are described as new (C. burlinghamiae, C. pallidoriederi and C. argenteolilacinus var. dovrensis). The sect. Riederi species possess morphological features similar to Phlegmacium group(s) and forms a phylogenetically isolated lineage, with no supported affinity to other phlegmacioid groups. Three taxa are known from both Europe and North America, two species are known only from North America and five only from Europe. Altogether, eight of the ten taxa are associated with conifers or northern (boreal-subalpine) deciduous trees (Betula spp.). Only two species occur in more temperate forests (Fagus forests), and no species have so far been found in thermophilous Quercus forests  相似文献   

13.
Strain DMKU-SP105T representing a novel yeast species was isolated from the external surface of a sugarcane leaf (Saccharum officinarum L.) collected from a sugarcane plantation field in Phichit province, Thailand. On the basis of sequence analysis of the D1/D2 region of the large subunit (LSU) rRNA gene and the internal transcribed spacer (ITS) region, the strain DMKU-SP105T differed by 7–16 substitutions in the D1/D2 region of LSU rRNA gene and 6–22 substitutions in the ITS region from a group of related species, Papiliotrema aspenensis, Papiliotrema odontotermitis, Papiliotrema rajasthanensis and Papiliotrema laurentii. A phylogenetic analysis based on the concatenated sequences of ITS region and the D1/D2 region of the LSU rRNA gene indicated that strain DMKU-SP105T belongs to the laurentii clade of Papiliotrema in the Tremellales and is distinct from other related species in the clade. It therefore represents a novel species of the genus Papiliotrema although the formation of basidiospores was not observed. The name Papiliotrema phichitensis f.a., sp. nov. is proposed. The type is DMKU-SP105T (=?CBS 13390T?=?BCC 61187T?=?NBRC 109699T).  相似文献   

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Two novel species of Diatrypaceae, Diatrypella tectonae and Peroneutypa mackenziei, were collected from dead wood in northern Thailand. The new species are introduced in this paper, with evidence from morphology and phylogenetic analyses. The new taxa are described, illustrated and compared with related taxa. Phylogenetic analyses of combined ITS and partial β-tubulin (β-tub) sequence data support their natural placements in the genera Diatrypella and Peroneutypa as new species.  相似文献   

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Colletotrichum spp. are causal agents of anthracnose disease in chili fruits and other tropical crops. The disease is increasing in chili fruits in Thailand and significantly reduces fruit quality and fruit production. Forty-eight isolates of Colletotrichum spp. associated with chili anthracnose were collected from different areas of Thailand during 2010–2015. Based on morphological characteristic identification, 10 isolates were shown to belong to the C. gloeosporioides species complex, 24 isolates belong to the C. acutatum species complex and 14 isolates to C. capsici. For molecular identification, two primer sets, ITS1/ITS4 and ACT528/ACT738, were used for amplification of the internal transcribed spacer of rRNA gene (ITS1–5.8S–ITS2) and partial region actin gene (ACT), respectively. The phylogenetic analysis of individual and combined ITS region and actin nucleotide sequences identified the collected isolates into 4 species: C. gloeosporioides, C. siamense, C. acutatum and C. capsici. The pathogenicity test demonstrated that all four species were pathogenic on intact unwounded and healthy fruits. These results indicated that C. capsici, C. acutatum, C. gloeosporioides and C. siamense were the causal agents of chili anthracnose disease.  相似文献   

19.
Gloeoporus Mont. is characterized by an easily separated gelatinous hymenophore and a continuous hymenium over the pore mouth. Recent molecular taxonomic and phylogenetic research showed that morphological grouping of Gloeoporus is polyphyletic. The lack of comprehensive phylogenetic studies of Gloeoporus exacerbates confusion in determining the taxonomic position of the genus. To delimit the genus Gloeoporus, we performed multi-locus phylogenetic analysis using the internal transcribed spacer (ITS) region, the nuclear large subunit ribosomal DNA (LSU), and the second-largest subunit of RNA polymerase II (rpb2). The phylogenetic analyses revealed that current delimitation of Gloeoporus is not monophyletic. Gloeoporus s.s. includes mostly clamped species lacking cystidia. Some species of Gloeoporus featuring simple septa and cystidia are proposed to be renamed to Meruliopsis. Two new species of Gloeoporus were also observed and they are named Gloeoporus africanus and Gloeoporus orientalis.  相似文献   

20.
The figwort genus Scrophularia (Scrophulariaceae), widespread across the temperate zone of the Northern Hemisphere, comprises about 250 species and is a taxonomically challenging lineage displaying large morphological and chromosomal diversity. Scrophularia has never been examined in a large-scale phylogenetic and biogeographic context and represents a useful model for studying evolutionary history in the context of reticulation. A comprehensively sampled phylogeny of Scrophularia was constructed, based on nuclear ribosomal (ITS) and plastid DNA sequences (trnQ-rps16 intergenic spacer, trnL-trnF region) of 147 species, using Bayesian inference and maximum likelihood approaches. Selected individuals were cloned. A combination of coding plastid indels and ITS intra-individual site polymorphisms, and applying Neighbor-Net and consensus network methods for adequate examination of within-dataset uncertainty as well as among-dataset incongruence, was used to disentangle phylogenetic relationships. Furthermore, divergence time estimation and ancestral area reconstruction were performed to infer the biogeographic history of the genus. The analyses reveal significant plastid-nuclear marker incongruence and considerable amounts of intra-individual nucleotide polymorphism in the ITS dataset. This is due to a combination of processes including reticulation and incomplete lineage sorting, possibly complicated by inter-array heterogeneity and pseudogenization in ITS in the presence of incomplete concerted evolution. Divergence time estimates indicate that Scrophularia originated during the Miocene in Southwestern Asia, its primary center of diversity. From there, the genus spread to Eastern Asia, the New World, Europe, Northern Africa, and other regions. Hybridization and polyploidy played a key role in the diversification history of Scrophularia, which was shaped by allopatric speciation in mountainous habitats during different climatic periods.  相似文献   

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