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1.
利用序列相关扩增多态性(SRAP)标记对中国半夏属植物5个种的亲缘关系进行了研究.38个引物组合在半夏属植物的5个种中共扩增出752条清晰的谱带,其中628条谱带具有多态性,多态性比率为83.51%,显示出较高的多态性比率;各物种间的遗传相似系数在0.6513~0.7312之间,聚类分析和主坐标分析结果表明,5种半夏属植物被聚为两大类:掌叶半夏单独聚为一类(Ⅱ),而其它4个种聚为一类(Ⅰ).第Ⅰ类可再分为A和B两个亚类:A亚类包括半夏和石蜘蛛;B亚类包括盾叶半夏和滴水珠.滴水珠和盾叶半夏的亲缘关系最近,其次是半夏和石蜘蛛,而掌叶半夏和其它4个种的亲缘关系都较远,这说明掌叶半夏与半夏属其它种呈姐妹群关系.本研究结果对我国半夏属植物资源的开发利用与保护具有重要意义.  相似文献   

2.
Polymerase chain reaction fragment length polymorphisms and nucleotide sequences for a cytochrome P450 gene encoding flavonoid-3',5'-hydroxylase, Hf1, were studied in 19 natural taxa of Petunia. Natural Petunia taxa were classified into six groups based on major insertion or deletion events that occurred only in intron II of the locus. The maximum parsimony method was used to calculate strict consensus trees based on nucleotide sequences in selected regions of the Hf1 locus. Petunia taxa were divided into two major clades in the phylogenetic trees. Petunia axillaris (including three subspecies), P. exserta, and P. occidentalis formed a clade with 100% bootstrap support. This clade is associated with a consistently inflexed pedicel, self-compatibility in most taxa, and geographical distribution in southern and western portions of the genus range. The other clade, which comprised the remainder of the genus is, however, less supported (up to 71% bootstrap); it is characterized by a deflexed pedicel in the fruiting state (except P. inflata), self-incompatibility, and a northeastern distribution. A nuclear gene, Hf1, seems to be a useful molecular marker for elucidating the phylogeny of the genus Petunia when compared with the nucleotide sequence of trnK intron of chloroplast DNA.  相似文献   

3.
蒟蒻薯属(Tacca)植物种间在形态上差别不大,导致分类上存在一定的困难。DNA条形码是一种利用短的DNA标准片段来鉴别和发现物种的方法。本研究利用核基因ITS片段和叶绿体基因trnH psbA, rbcL, matK片段对蒟蒻薯属6个种的DNA条形码进行研究,对4个DNA片段可用性,种内种间变异,barcode gap进行了分析,采用Tree based和BBA两种方法比较不同序列的鉴定能力。结果显示:单片段ITS正确鉴定率最高,片段组合rbcL+matK正确鉴定率最高。支持CBOL植物工作组推荐的条码组合rbcL+matK可作为蒟蒻薯属物种鉴定的标准条码,建议ITS片段作为候选条码。丝须蒟蒻薯Tacca integrifolia采自西藏的居群与马来西亚居群形成了2个不同的遗传分支,且两者在形态上也存在一定的差异,很可能是一个新种。  相似文献   

4.
The Potamogeton compressus group is a complex of three to five closely related species with a circumpolar distribution in the Northern Hemisphere. Multivariate morphometric analyses (principal component analysis, cluster analysis, canonical and classificatory discriminant analyses) were used to elucidate the patterns of variation within this group and to test the morphological differentiation of the species recognized in the current literature. From the entire distribution range, 156 specimens of the group were included in the numerical methods. Results from morphological comparison are discussed in relation to molecular data, reproductive behaviour and geographical distribution. Morphometric analyses provided evidence that this complex can be clearly divided into three groups, one of which was subdivided mainly on the basis of allopatric occurrence and genetic differentiation. These groups correspond to four species accepted here: P. acutifolius (temperate regions of Europe), P. compressus (boreal and temperate regions of Europe and Asia), P. manchuriensis (northeastern China and Russian Far East) and P. zosteriformis (boreal and temperate regions of North America). Two species, P. acutifolius and P. compressus, are partly sympatric, but clearly differentiated morphologically and genetically, and effectively isolated reproductively. Endemic P. manchuriensis is characterized by a unique combination of characters and an occurrence in a limited geographical area. Allopatric P. zosteriformis is weakly differentiated morphologically from P. compressus, but differs markedly in molecular markers correlated with geographical differentiation. It may represent a cryptic species. In contrast, a recently suggested concept of southern Siberian P. henningii was not supported by our analyses. Plants so named are considered here as slender phenotypes of the widespread and variable P. compressus. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 170 , 112–130.  相似文献   

5.
The planktonic foraminiferal morpho-species Globoconella inflata is widely used as a stratigraphic and paleoceanographic index. While G. inflata was until now regarded as a single species, we show that it rather constitutes a complex of two pseudo-cryptic species. Our study is based on SSU and ITS rDNA sequence analyses and genotyping of 497 individuals collected at 49 oceanic stations covering the worldwide range of the morpho-species. Phylogenetic analyses unveil the presence of two divergent genotypes. Type I inhabits transitional and subtropical waters of both hemispheres, while Type II is restricted to the Antarctic subpolar waters. The two genetic species exhibit a strictly allopatric distribution on each side of the Antarctic Subpolar Front. On the other hand, sediment data show that G. inflata was restricted to transitional and subtropical environments since the early Pliocene, and expanded its geographic range to southern subpolar waters ~700 kyrs ago, during marine isotopic stage 17. This datum may correspond to a peripatric speciation event that led to the partition of an ancestral genotype into two distinct evolutionary units. Biometric measurements performed on individual G. inflata from plankton tows north and south of the Antarctic Subpolar Front indicate that Types I and II display slight but significant differences in shell morphology. These morphological differences may allow recognition of the G. inflata pseudo-cryptic species back into the fossil record, which in turn may contribute to monitor past movements of the Antarctic Subpolar Front during the middle and late Pleistocene.  相似文献   

6.
The high copy dTph1 transposon system of Petunia (Solanaceae) is one of the most powerful insertion mutagens in plants, but its activity cannot be controlled in the commonly used mutator strains. We analysed the regulation of dTph1 activity by QTL analysis in recombinant inbred lines of the mutator strain W138 and a wild species (P. integrifolia spp. inflata). Two genetic factors were identified that control dTph1 transposition. One corresponded to the ACT1 locus on chromosome I. A second, previously undescribed locus ACT2 mapped on chromosome V. As a 6-cM introgression in W138, the P. i. inflata act1(S6) allele behaved as a single recessive locus that fully eliminated transposition of all dTph1 elements in all stages of plant development and in a heritable fashion. Weak dTph1 activity was restored in act1S6/ACT2S6 double introgression lines, indicating that the P. i. inflata allele at ACT2 conferred a low level of transposition. Thus, the act1S6 allele is useful for simple and predictable control of transposition of the entire dTph1 family when introgressed into an ultra-high copy W138 mutator strain. We demonstrate the use of the ACT1W138/act1S6 allele pair in a two-element dTph1 transposition system by producing 10,000 unique and fixed dTph1 insertions in a population of 1250 co-isogenic lines. This Petunia system produces the highest per plant insertion number of any known two-element system, providing a powerful and logistically simple tool for transposon mutagenesis of qualitative as well as quantitative traits.  相似文献   

7.
Two species of the calanoid copepod Pseudocalanus, P. acuspes and P. elongatus, have been reported from the Baltic and North Seas. Morphometric analysis based on Frost (Can J Zool 67:525–551, 1989) did not identify the species in samples collected during the German GLOBEC program; the majority of measurements fell outside reported ranges for Baltic and North Sea specimens. A multiplexed species-specific PCR (SS-PCR) protocol was designed from a ~700 bp sequence of mitochondrial cytochrome oxidase I (mtCOI), with primers designed to amplify regions of different sizes for the two species to allow detection by gel electrophoresis. The accuracy and reliability of the multiplexed SS-PCR reaction was confirmed by sequencing the mtCOI region. Preliminary SS-PCR analysis of geographic distributions of the two species indicated that P. acuspes occurred exclusively at sampling sites in the Baltic Sea, whereas P. elongatus was found in the southern North Sea and at one site in the Baltic. The SS-PCR protocol can be used for routine identification of the two species for studies of population, community and ecosystem dynamics.  相似文献   

8.
Yang FS  Qin AL  Li YF  Wang XQ 《PloS one》2012,7(5):e37196
The complex tectonic events and climatic oscillations in the Qinghai-Tibetan Plateau (QTP), the largest and highest plateau in the world, are thought to have had great effects on the evolutionary history of the native plants. Of great interest is to investigate plant population genetic divergence in the QTP and its correlation with the geologic and climatic changes. We conducted a range-wide phylogeographical analysis of M. integrifolia based on the chloroplast DNA (cpDNA) trnL-trnF and trnfM-trnS regions, and defined 26 haplotypes that were phylogenetically divided into six clades dated to the late Tertiary. The six clades correspond, respectively, to highly differentiated population groups that do not overlap in geographic distribution, implying that the mountain ranges acting as corridors or barriers greatly affected the evolutionary history of the QTP plants. The older clade of M. integrifolia only occurs in the southwest of the species' range, whereas the distributions of younger clades extend northeastward in the eastern QTP, suggesting that climatic divergence resulting from the uplift of the QTP triggered the initial divergence of M. integrifolia native to the plateau. Also, the nrDNA ITS region was used to clarify the unexpected phylogenetic relationships of cpDNA haplotypes between M. integrifolia and M. betonicifolia. The topological incongruence between the two phylogenies suggests an ancestral hybridization between the two species. Our study indicates that geographic isolation and hybridization are two important mechanisms responsible for the population differentiation and speciation of Meconopsis, a species-rich genus with complex polyploids.  相似文献   

9.
Uromyces appendiculatus, inclusive of three varieties, is distinguished from U. vignae primarily by the position of urediniospore germ pores and putative host specificity. However, opinions concerning these morphological and physiological features as taxonomic characters have varied greatly, and distinction of these species has often been confused. To clarify the taxonomy of these two species, morphological features of urediniospores and teliospores of 225 rust fungus specimens on species of Phaseolus, Vigna, Apios, Lablab, and Dunbaria were examined by light microscopy and scanning electron microscopy. Forty-five specimens were subjected to molecular phylogenetic analyses. As a result, the position of germ pores in urediniospores and the teliospore-wall thickness were considered as good characters to separate three morphological groups. In molecular analyses, the specimens fell into two and three clades based on the nucleotide sequence at D1/D2 domain of LSU rDNA and ITS regions, respectively. One of the D1/D2 clades corresponded to one morphological group whereas another D1/D2 clade included two other morphological groups. In contrast, each of the three ITS clades corresponded to a separate morphological group. Neither morphological groups nor molecular clades were host limited. It is suggested that the three morphological groups that corresponded to three distinct ITS clades constitute distinct species.Contribution no. 186 from the Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

10.
With the aim of making clear the boundaries between species in thePoa acroleucahisauchii-nipponica aggregate, chromosomes and morphological features of 746 collections gathered from 125 localities in Japan were examined. For morphological observations, the voucher specimens of 95 collections whose chromosome numbers were reported previously (Tateoka, 1985) were also used. Tetraploids (2n=28) and hexaploids (2n=42), as well as a few pentaploids which were the hybrids between 4× and 6×, were found. By examining morphological features of these collections, two groups were recognized in tetraploids and one in hexaploids. The two tetraploid groups corresponded toPoa acroleuca Steud. andP. hisauchii Honda, and the hexaploid group toP. nipponica Koidz. It was confirmed that the hairiness on the internerve surface of lemma, ligule hairiness and the length ratio of anther/ lemma are the most important features for discriminating between these species; panicle shape, leaf shape and anther length are also helpful for the identification. The ambiguity of the boundaries between species which was hitherto present in the taxonomy of this species aggregate was unrelated to the creation of nature itself but was attributable to the insufficiency of our research work.  相似文献   

11.
12.
伞形科囊瓣芹属的表型分析   总被引:1,自引:0,他引:1  
选取伞形科(Apiaceae)囊瓣芹属(Pternopetalum Franchet)32个分类群的60个形态学性状,利用DELTA系统的UPGMA算法进行了聚类分析。结果表明属下形成以五匹青(P.vulgare(Dunn)Hand.-Mazz.)和东亚囊瓣(P.tanakae(Franchet&Sav.)Hand.-Mazz.)为代表的两个主要表征群。两个主要表征群的分类结构和各自所包含的类群基本相应于前人研究中本属两个组的属下处理。根据全面相似性分析的结果和部分形态学特征的评估,确认了属下6个种的复合群:即五匹青、囊瓣芹(P.davidii Franchet)、散血芹(P.botrychioides(Dunn)Hand.-Mazz.)、洱源囊瓣芹(P.molle(Franchet)Hand.-Mazz.)、澜沧囊瓣芹(P.de-lavayi(Franchet)Hand.-Mazz.)和东亚囊瓣芹复合群。根据形态学特征在表型树上的分布分析表明:伞形花序的着生位置、花柱的形态、花柱基的形状和萼齿的大小等生殖特征可能是属下早期分化的关键性性状。属下主要变异类型(种的复合群和典型狭域特有种)对不同海拔区域和小生境的依赖,以及不显著的形态学分化表明:对横断山区较高的异质性生境的生态适应是囊瓣芹属类群多样化过程后期的一个重要特征。  相似文献   

13.
采用真菌核糖体基因转录间隔区(ITS)通用引物,PCR分别扩增了Phytophthora sojae的5个菌株(Pg1、Pg2、Pg3、CN1和S317)和1个P. medicaginis (菌株44390)的ITS1与ITS2,并对PCR产物进行了序列测定。根据Bioedit软件中的neighbour-joining methods分析法将上述序列和Genbank中已登录的P. sojae、P. medicaginis、P. megasperma和P.trifolii等4个形态学种10个登录菌株的ITS1与ITS2碱基序列进行聚类分析。结果是聚类组与形态学种有一定差别,4个种16个菌株分成7个聚类组。结果表明,分别属于同一形态学种且可聚为一组的不同个体之间的ITS碱基序列遗传相似性最高,但是也具有一定的多样性;形态学上属于不同种的个体的ITS可以聚为一组。上述结果提示L41385可能不属于P. sojae, L41380可能属于是P. trifolii,P. megasperma仍是一个复合种。同时提示ITS DNA碱基序列可以区分形态学种。  相似文献   

14.
Wild and cultured specimens of Prorocentrum lima (Ehrenb.) F. Stein from 26 widely different areas in 13 countries were examined in order to determine consistent characters for delimiting species boundaries in this taxon. The morphological characters valve shape, valve size, valve ornamentation, number and shape of valve pores, number and shape of marginal pores, and periflagellar platelets were observed using LM and SEM, and two molecular genetic regions were sequenced. We identified stable morphological characters that were consistent among wild specimens and all cultures, which were valve shape, valve ornamentation, and number and arrangement of periflagellar platelets. All cultures of P. lima identified by these characters formed a monophyletic group in phylogenetic analyses based on the two genes, which, however, included the species Prorocentrum arenarium. P. arenarium was determined to be within the range of morphological variation of P. lima, and therefore we synonymize the two taxa. Within this monophyletic group, P. lima was divided into several subclades in the all phylogenetic analyses. There were no morphological characters specifically related to any one subclade. The subclades appeared to correlate broadly to sample collection regions, suggesting that geographically separated populations may have become genetically distinct within this epi‐benthic species. We have emended species boundaries in P. lima.  相似文献   

15.
An earlier study of the morphological variation in the circumpolar genus Dryas in Greenland revealed that populations in east Greenland are highly variable and this variation was interpreted as a hybrid zone between D. octopetala and D. integrifolia. It was proposed that populations of Dryas in east Greenland immigrated postglacially from Svalbard. The purpose of our study was to investigate the population structure of the Dryas integrifolia-octopetala complex using a combination of morphological and genetic characters. Populations of Dryas were sampled in Greenland, Svalbard, Iceland and north Scandinavia (Sweden). The morphological traits clearly separated west Greenland from Svalbard, Iceland and north Scandinavia. A large number of individuals from east Greenland and some from north Greenland could be interpreted as hybrids between the morphs. The genetic pattern was, however, partly different as the greatest amount of differentiation among regions was found between west and north Greenland (FRT = 0.65). The highest degree of genetic variation appeared within east Greenland. This was in accordance with the putative hybrid origin of the populations, as concluded based on the morphological results. The total amount of genetic differentiation found among the six regions (FRT = 0.61) was larger than between the two species (FRT = 0.44). The genetic pattern matched the proposed postglacial migration routes.  相似文献   

16.
Madrid H  Gené J  Cano J  Silvera C  Guarro J 《Mycologia》2010,102(5):1193-1203
Sporothrix inflata is a saprobic member of the Ophiostoma stenoceras-Sporothrix schenckii species complex, reported mainly from soil. Ophiostoma bragantinum, an ascomycete described from Brazil, has been proposed as its possible teleomorph. Previous studies revealed that Sporothrix inflata is phenotypically and genetically variable, suggesting the existence of cryptic species. During a continued survey on the biodiversity of microfungi from different countries, seven isolates morphologically similar to S. inflata were obtained from soil samples collected in Spain and USA. In this study their phenotypic features and phylogenetic relationships were assessed. DNA sequence data of two nuclear loci revealed that these isolates correspond to two unnamed clades in S. inflata s.l., one of which also included the type strain of Humicola dimorphospora, a species that traditionally has been considered a synonym of S. inflata. These two groups are proposed herein as Sporothrix brunneoviolacea sp. nov. and Sporothrix dimorphospora comb. nov. S. brunneoviolacea is characterized phenotypically by the production of a diffusible violet-brown pigment in culture and mostly globose, pigmented, lateral blastoconidia. On the other hand S. dimorphospora lacks diffusible pigments and shows mostly subglobose to obovoid pigmented lateral blastoconidia. In contrast to the type strain of S. inflata S. brunneoviolacea and S. dimorphospora assimilate raffinose. The phylogenetic analysis suggested that the proposed anamorph-teleomorph connection between S. inflata and O. bragantinum might not be correct.  相似文献   

17.
The Sphaerophorus globosus complex (Lecanorales, lichenized Ascomycota) shows a large morphological variation, and three relatively distinct morphotypes can be distinguished in parts of the distribution area. Here, we utilize a multigene‐based maximum‐parsimony approach (nITS+ LSU rDNA, mtSSU rDNA, β‐tubulin, and actin) to investigate whether these morphotypes constitute distinct species. The results show that there are at least two well‐supported monophyletic groups that we interpret as phylogenetic species within the S. globosus complex. These species do not completely correspond to the predefined morphotypes. One group, an apparently undescribed species, contains noncoralloid specimens from the North American Pacific Northwest. The other group, S. globosus, consists of two well‐supported monophyletic groups: one contains coralloid epiphytic specimens from the North American Pacific Northwest that are morphologically indistinguishable from epiphytic specimens from Europe and are presently interpreted as belonging to the same species and the other is morphologically variable and contains terrestrial specimens from Europe, North America, and southernmost South America and coralloid epiphytic and epilithic specimens from Europe. The results suggest that the population in southernmost South America originated by long‐distance dispersal from arctic populations in the Northern Hemisphere.  相似文献   

18.
The authors carried out isoenzyme characterization and genotype comparison studies for Phlebotomus chinensis and Phlebotomus sichuanensis images collected from their holotype/paratype original localities: West Mountain, West Suburb, Beijing and Lixian County, Sichuan Province. Numerical analysis was carried out and the dendrogram of four species of Adlerius was drawn up according to morphological characteristics of these four species. The results showed that P. chinensis and P. sichuanensis can be identified enzymatically in PGM and the MDH-2 allele also differs in P. chinensis from Beijing and. P. sichuanensis. The dendrogram of four Adlerius species showed that P. fengi and P. longiductus are very similar and they clustered first, then P. sichuanensis combine with them to form a combined group. P. chinensis is a separate group from other three. These two groups come to combine at last. Above results have proved that P. sichuanensis is an isolate species instead of a so-called large type P. chinensis.  相似文献   

19.
Abstract:  Planococcus ficus (Signoret) and Planococcus citri (Risso) (Hom., Pseudococcidae) are important phytophagous components in different agroecosystems. The two species may coexist in the same environment and are most difficult to distinguish by morphological features. The aim of this study was to find genetic markers suitable for distinguishing P. ficus from P. citri , to assist in the rapid identification of field specimens. By using synthetic sex pheromone-baited traps, pure male populations of both species were collected from a vineyard and from a citrus orchard in northern Sardinia, Italy. Individual males of citrus and vine mealybugs were preliminarily examined by the random amplification of polymorphic DNA (RAPD) technique. Among twelve 10-mer random primers, the oligonucleotide OPL-12 generated several markers suitable for distinguishing between the two species. This primer was then used to characterize individual males and females of both mealybug species collected near pheromone-baited traps in vineyards and orange orchards from different geographic areas. Reference samples from other regions of southern Italy were also included. A clear differentiation of the two species was accomplished according to their pattern of amplification, thus confirming a high level of intra-specific genetic homogeneity. Consequently, two fragments of the cytochrome c oxidase I gene from P. citri and P. ficus were compared and two pairs of species-specific polymerase chain reaction (PCR) primers were developed based on diverging sequences. These primers allowed sensitive and reliable PCR identification of both males and females of P. citri and of P. ficus of different geographic origin.  相似文献   

20.
Arthropod‐borne diseases are important causes of morbidity and mortality. The identification of vector species relies mainly on morphological features and/or molecular biology tools. The first method requires specific technical skills and may result in misidentifications, and the second method is time‐consuming and expensive. The aim of the present study is to assess the usefulness and accuracy of matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) as a supplementary tool with which to identify mosquito vector species and to invest in the creation of an international database. A total of 89 specimens belonging to 10 mosquito species were selected for the extraction of proteins from legs and for the establishment of a reference database. A blind test with 123 mosquitoes was performed to validate the MS method. Results showed that: (a) the spectra obtained in the study with a given species differed from the spectra of the same species collected in another country, which highlights the need for an international database; (b) MALDI‐TOF MS is an accurate method for the rapid identification of mosquito species that are referenced in a database; (c) MALDI‐TOF MS allows the separation of groups or complex species, and (d) laboratory specimens undergo a loss of proteins compared with those isolated in the field. In conclusion, MALDI‐TOF MS is a useful supplementary tool for mosquito identification and can help inform vector control.  相似文献   

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