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1.
喜马拉雅-横断山区钟花报春居群遗传多样性及遗传分化 总被引：8，自引：0，他引：8
应用简单序列重复区间(ISSR,Inter-simple sequence repeat)分子标记,对喜马拉雅．横断山区钟花报春(Primula sikkimensis)进行居群遗传分析。用10个ISSR引物对13个居群的254个个体进行扩增,共检出91条扩增片段,全部为多态带,总的多态位点百分率为100％。Shannon多样性指数(Ho)从0．2293到0．4016,居群水平上平均值(HPCP)为0．3211,物种水平上(Hsp)为0．5576。利用分子方差(AMOVA)软件分析,其结果为：在总的遗传变异中,有50．28％的遗传变异属于居群之间;用POPGENE计算出的遗传分化系数GST=0．4127,即居群间的分化变异占居群总遗传变异的41．27％,比AMOVA分析所得的结果偏低。居群间遗传距离变化范围从0．0780到0．4748,遗传一致度(I)的变化范围从0．6220到0．9250。居群间的基因流Nm=0．7114,相对低的基因流可能是维持钟花报春居群遗传分化的原因。这表明,喜马拉雅．横断山区钟花报春的13个居群具有很高的遗传多样性,并且居群间的分化也很大。 相似文献
2.
XIAO-HUA JIN TING ZHANG ZHI-JIAN GU DE-ZHU LI 《Botanical journal of the Linnean Society. Linnean Society of London》2007,154(2):283-288
The karyotypes of ten species of Holcoglossum (Orchidaceae), a highly endangered and diversified genus from China, were investigated to study the infrageneric relationships, biogeography, and speciation patterns in the Hengduan Mountains. The karyotype formulae of the studied species are as follows: 2 n = 38 = 20m + 18sm in H. subulifolium , 2 n = 38 = 22m + 16sm in H. amesianum , 2 n = 38 = 26m + 12sm (6 SAT) in H. lingulatum , 2 n = 38 = 26m + 12sm in H. wangii , 2 n = 38 = 10m + 28sm in H. kimballianum , 2 n = 38 = 14m + 22sm + 2st in H. flavescens , 2 n = 38 = 24m + 12sm + 2st in H. rupestre , 2 n = 38 = 14m + 20sm + 4st in H. sinicum , 2 n = 38 = 16m + 14sm + 8st in H. weixiense , and 2 n = 76 in H. tsii . The karyotypes of two tropical species, H. amesianum and H. subulifolium , are the most primitive in the genus, whereas those of four temperate alpine species, H. sinicum , H. rupestre , H. weixiense , and H. flavescens , are more advanced. H. tsii is a tetraploid and H. rupestr e may be one of its ancestors. The low frequency of polyploidy in Holcoglossum in the Hengduan Mountains region supports the conclusion that chromosome stasis during rapid speciation is common there. © 2007 The Linnean Society of London. Botanical Journal of the Linnean Society , 2007, 154 , 283–288. 相似文献
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LIV BORGEN ILIA LEITCH ARNOLDO SANTOS-GUERRA 《Botanical journal of the Linnean Society. Linnean Society of London》2003,141(4):491-501
Two diploid species of hybrid origin, Argyranthemum lemsii and A. sundingii , have been described from different valleys in the Anaga peninsula, north-east Tenerife. They have previously been shown to originate from hybridization between the same parental species, the montane A. broussonetii and the coastal A. frutescens , A. broussonetii being the chloroplast donor in one valley and A. frutescens in the other. The specific status of the two hybrid species has been questioned. In this study we used karyotype analysis, FISH, and GISH to address the question of multiple diploid hybrid speciation. GISH did not discriminate clearly between the parental genomes, but differential labelling was observed in separate hybrid populations, indicating different chromosomal rearrangements in different valleys. Small karyotype differences and local loss of rDNA were also observed. Thus separate origins of the same hybrid combination in different valleys in Tenerife have been verified. Our results add some support to the recognition of two species of hybrid origin, but the case serves to illustrate some of the many problems connected with the species concept in plants. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 491–501. 相似文献
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Hamid Boroumand;Reihaneh Saberi-Pirooz;Soheila Shafiei Bafti;Wolfgang Böhme;Faraham Ahmadzadeh; 《Zoologica scripta》2024,53(3):312-322
Mesalina watsonana is a well-known species of small lacertid lizards with an extensive species distribution that exhibits high genetic diversity. The species has a wide distribution range in Iran, some parts of Turkmenistan, Afghanistan, Pakistan, and northwest India. This study aims to generate phylogenetic and phylogeographic evidence to derive taxonomic recommendations supporting. Furthermore, this species can be used as a model for examining Iranian Platuea's historical biogeography. We conducted a very detailed sampling of its distribution and used genetic approaches. Phylogenetic analyses were done implementing two mitochondrial (Cytb and 16S) and one nuclear (C-mos) gene fragments. Combination of these results indicated that seven well-supported distinct clades exist within this species complex, i.e. Kerman clade, Esfarayen clade, Halil clade, Ardestan clade, M. watsonana clade, Bardaskan Clade, and Khuzestan Clade in Iran. Also, our results revealed that several distinct clades diverged due to geologic events when the Dasht-e-Kavir and the Zagros Mountains were formed. It seems that the ancestor of M. watsonana spread to Iranian Plateau before the formation of the Zagros Mountains. Orogenic activities of the Zagros Mountains and the formation of deserts have influenced the separation of these lineages from the Late Miocene by allopatric speciation. Generally, our findings suggest that each of the seven clades corresponding to distinct geographic regions deserves to be elevated to the species level. 相似文献
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EVIATAR NEVO ELENA IVANITSKAYA MARIA GRACIA FILIPPUCCI AVIGDOR BEILES 《Biological journal of the Linnean Society. Linnean Society of London》2000,69(2):263-281
The major initial mechanism of speciation in subterranean blind mole rats, Spalacidae, is chromosomal, primarily through Robertsonian rearrangements. Here we highlight another scenario of chromosomal rearrangement leading to ecological speciation and adaptive radiation apparently initiated by pericentric inversions and genie divergence to different ecologies in mole rats in Jordan. We analysed karyotype, allozyme, size and ecological diversity across the range of mole rats in Jordan from mesic Irbid in the north to xeric Wadi Musa (Petra region) in the south, a transect of 250 km. We examined mole rats for chromosome ( N =71), size ( N =76), and allozyme ( N =67) diversities, encoded by 32 loci, in 12 populations of the Spalax ehrenbetgi superspecies in Jordan. By a combination of chromosome morphology, genetic distance, body size and ecogeography, we identified four new putative biological species. All species (except two animals in Madaba) share 2 n = 60 but vary in chromosome morphology, caused by pericentric inversions and/or centromeric shifts. The 'north Moav' species is karyotypically polymorphic for 2 n (2 n = 60; including locally also two animals with 2 n = 62). The distribution of the four species is associated with ecogeographical different domains and climatic diversity. Genetic diversity indices were low, but like chromosome arms (NFa) were positively correlated with aridity stress. Discriminant analysis correctly classified 91% of the individuals into the four species utilizing combinatorially chromosome, allozyme and size diversities. It is hypothesized that mole rat evolution underground is intimately associated with climatic diversity stress above ground. 相似文献
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J. J. B. Gill A. J. Cain 《Biological journal of the Linnean Society. Linnean Society of London》1986,28(3):315-320
The karyotype of Cepaea vindobonensis (Pfeiffer) (2 n = 50) is defined and compared with those of C. sylvatica (Draparnaud), C. nemoralis (L.) and C. hortensis (Müller). Cepaea vindobonesis shares its chromosome number with C. sylvatica. The genus Cepaea thus consists of two pairs of species, one with 2 n = 50 the other with 2 n = 44. The karyotype of C. vindobonensis is distinct from that of C. sylvatica as it lacks any discontinuity in its range of chromosome length and has all three of its longest chromosome pairs nearly identical. The two 2 n = 50 species both have an unusual meiotic bivalent showing a 'satellite-type' structure. It is apparent that the 2 n = 50 species are more closely related to each other than to the 2 n = 44 species. No precise definition of the evolutionary history can be given but a working hypothesis is suggested. 相似文献
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本文首次报道产于我国华北地区风毛菊属（ＳａｕｓｓｕｒｅａＤＣ．）４种植物的染色体数目和核型。四个种的染色体数目均是２ｎ＝２６,都是２倍体。它们的核型是：糠风毛菊（Ｓ．Ｐａｌｅａｔａ）Ｚｎ＝２ｘ＝２６＝１８ｍ＋６ｓｍ＋２ｓｔ,属２Ｂ型,华北风毛菊（Ｓ．ｍｏｎｇｏｌｉｃａ）Ｚｎ＝２ｘ＝２６＝１４ｍ＋４ｓｍ＋８ｓｔ,属２Ｂ型;狭苞凤毛菊（Ｓ．ｄｉｅｌｓｉａｎａ）Ｚｎ＝２ｘ＝２６＝８ｍ＋１２ｓｍ＋６ｓｔ,属２Ｃ型;银背凤毛菊（Ｓ．ｎｉｖｅａ）２ｎ＝２ｘ＝２６＝１８ｍ＋６ｓｍ＋２ｓｔ,属２Ａ型。染色体中均未发现随体。 相似文献
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用ＡＳＧ法对三叶木通（Ａｋｅｂｉａ ｔｒｉｆｏｌｉａｔａ）根、茎尖细胞进行染色体制片,探讨其染色体组型。结果表明：三叶木通核型为２ｎ＝２Ｘ＝１６＝１０Ｍ＋２ＳＭ＋２ＳＴ＋２Ｔ,Ｘ＝８;２Ｂ类型,第２号染色体上有一对随体。三叶木通细胞中存在有混倍性现象,实生苗中２ｎ＝４Ｘ＝３２的四倍性细胞占７．９％;秋水仙素诱变苗、根茎占３１．８％～３７．９％。 相似文献
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基于matK基因的松属白皮松组分子系统发育分析(英文) 总被引：4，自引：0，他引：4
基于matK基因对松属(Pinus L.)白皮松组(sect.Parrya Myre)进行了分子系统发育分析。白皮松组为一个并系类群,因为白松组的成员与该组(包括越南的扁叶松(P.krempfii Lecomte))的亚洲成员形成一个强烈支持的分支(靴带值92％)。在这个分支中,白松组的3个代表种形成一个稳定的单系,而白皮松组的亚洲成员之间系统发育关系不明确。扁叶松和西藏白皮松(P.gerardiana Wall.ex D.Don)聚在一起,但只有61％的支持率。虽然在以前4个cpDNA基因序列分析时五针白皮松(P.squamata X.W.Li)与白皮松(P.bungeana Zucc.ex Loud.)和西藏白皮松形成一个单系,但在本文的分析中三者的关系不明确。在邻接树和多数一致简约树上,北美的白皮松组成员形成一个支持率低的分支。北美的subsect.Balfourianae Engelm.亚组(包括P.aristata Engelm.)是一个单系,但支持率较低。美洲另外两个亚组subsect.Cembroides Englem.和subsect.Rzedowskianae Carv.的组间和组内关系不确定,它们在严格一致简约树上形成一个多歧分支。 相似文献
10.
Santosh Kumar Rana Hum Kala Rana Jacob B. Landis Tianhui Kuang Juntong Chen Hengchang Wang Tao Deng Charles C. Davis Hang Sun 《植物学报(英文版)》2024,66(6):1192-1205
The mountains of Southwest China comprise a significant large mountain range and biodiversity hotspot imperiled by global climate change. The high species diversity in this mountain system has long been attributed to a complex set of factors, and recent large-scale macroevolutionary investigations have placed a broad timeline on plant diversification that stretches from 10 million years ago (Mya) to the present. Despite our increasing understanding of the temporal mode of speciation, finer-scale population-level investigations are lacking to better refine these temporal trends and illuminate the abiotic and biotic influences of cryptic speciation. This is largely due to the dearth of organismal sampling among closely related species and populations, spanning the incredible size and topological heterogeneity of this region. Our study dives into these evolutionary dynamics of speciation using genomic and eco-morphological data of Stellera chamaejasme L. We identified four previously unrecognized cryptic species having indistinct morphological traits and large metapopulation of evolving lineages, suggesting a more recent diversification (~2.67-0.90 Mya), largely influenced by Pleistocene glaciation and biotic factors. These factors likely influenced allopatric speciation and advocated cyclical warming-cooling episodes along elevational gradients during the Pleistocene. The study refines the evolutionary timeline to be much younger than previously implicated and raises the concern that projected future warming may influence the alpine species diversity, necessitating increased conservation efforts. 相似文献
11.
The present paper deals with the karyotype analysis of 6 species of Elymuswhich are native to Qinghai-Tibetan plateau. The number of somatic chromosomes in roottip cells of the 6 species and their karyotypes are reportad here for the first time, and they areall hexaploid, with 2n=6x=42. The karyotype formulae are as follows: E. melantherus,2n=6x=42=32m+10sm, E. kengii, 2n=6x=42=34m+8sm, E grandiglumis, 2n=6x=42=30 m+12 sm, E. laxiflorus, 2n=6x=42=32 m +10 sm, E. kokonoricus, 2n+6x=42=34 m +8 sm, E. longiglumis, 2n+6x=42=34 m+8 sm. No satellites have been founded in the 6species and all the karyotypes belong to 1B or 2B type: 相似文献
12.
XIAO-LAN ZHANG YONG-MING YUAN XUE-JUN GE 《Botanical journal of the Linnean Society. Linnean Society of London》2007,154(2):225-232
The Hengduan Mountains are the core region of the Himalaya hotspot, and are renowned for their high levels of endemism. Gentiana atuntsiensis and G. striolata are two closely related and morphologically similar species endemic to this region. In this study, inter-simple sequence repeat (ISSR) markers were used to investigate the genetic structure within these two species, as well as the differentiation between them. An analysis of molecular variance-derived estimate demonstrated only 13.5% of genetic differentiation between the two species. Considering their adjacent distribution patterns, low genetic divergence, and clear clustering into two groups, it is hypothesized that the two species arose from a rapid and recent speciation event induced mainly by geographical isolation. A relatively high level of genetic diversity was revealed in each species (Shannon's index of diversity: H sp = 0.324 and 0.391; H pop = 0.225 and 0.274; for G. atuntsiensis and G. striolata , respectively). Most of the genetic variation was partitioned within populations ( Ø ST = 0.232 and 0.226 in G. atuntsiensis and G. striolata , respectively). The large population sizes, outcrossing breeding system, and small, light seeds that disperse widely may explain the genetic structure in both species. © 2007 The Linnean Society of London. Botanical Journal of the Linnean Society , 2007, 154 , 225–232. 相似文献
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Karyotypes of Saudi gazelle (2n = 47 female, 2n = 50/51 male) are presented for the first time. The three karyotypes shown here vary in the numbers of metacentric chromosomes, but the cause of this variation is not yet known. Although Saudi gazelle are often regarded as a subspecies of Dorcas gazelle, the chromosome numbers and karyotypes of Saudi gazelle are too different from Dorcas gazelle (2n = 30 female, 2n = 31 male) for them to be considered a subspecies. It is also unlikely that these species would interbreed. In view of the present findings, the taxonomic status of this highly endangered gazelle needs to be resolved as soon as possible. 相似文献
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SEBASTIEN DELARBRE SIMONETTA GATTI MASSIMO SCAGLIA MICHEL DRANCOURT 《The Journal of eukaryotic microbiology》2001,48(4):471-474
Encephalitozoon hellem is a microsporidian species responsible for opportunistic infections in AIDS patients. Use of a novel chitinase-based method allowed unsheared chromosomal DNA to be recovered from eleven E. hellem isolates derived from three geographic regions. All isolates were typed by 18S rDNA sequencing, which showed that they belonged to intemal transcribed spacer type 1. After ethidium bromide staining, pulsed-field gel electrophoresis (PFGE) analysis discriminated two new karyotypes comprising 7 and 8 chromosomal bands respectively, ranging in size from 205- to 272-kb pairs. Genomic size was estimated to be 2.39 Mb. Our data indicate PFGE is useful for typing E. hellem and confirms genetic diversity among E. hellem genotypes. 相似文献
15.
基于matK基因对松属(Pinus L.)白皮松组(sect.Parrya Myre)进行了分子系统发育分析.白皮松组为一个并系类群,因为白松组的成员与该组(包括越南的扁叶松(P.krempfii Lecomte))的亚洲成员形成一个强烈支持的分支(靴带值92%).在这个分支中,白松组的3个代表种形成一个稳定的单系,而白皮松组的亚洲成员之间系统发育关系不明确.扁叶松和西藏白皮松(P. gerardiana Wall.ex D.Don)聚在一起,但只有61%的支持率.虽然在以前4个cpDNA基因序列分析时五针白皮松(P.squamata X.W.Li)与白皮松(P.bungeana Zucc.ex Loud.)和西藏白皮松形成一个单系,但在本文的分析中三者的关系不明确.在邻接树和多数一致简约树上,北美的白皮松组成员形成一个支持率低的分支.北美的subsect.Balfourianae Engelm.亚组(包括P.aristata Engelm.)是一个单系,但支持率较低.美洲另外两个亚组subsect.Cembroides Englem.和subsect.Rzedowskianae Carv.的组间和组内关系不确定,它们在严格一致简约树上形成一个多歧分支. 相似文献
16.
广义烙铁头属三种烙铁头的核型及分类地位初步探讨 总被引：2，自引：0，他引：2
报道３种烙铁头蛇的核型。其中,烙铁头２ｎ＝３６＝１６Ｍ（１４Ｖ＋２ＳＶ／Ｖ）＋２０ｍ,ＺＷ型性决定,Ｚ为Ｖ型,Ｗ为ＳＩ／ＳＶ型,Ｚ明显大于Ｗ;菜花烙铁头２居群２ｎ＝３６＝１６Ｍ（１４Ｖ＋２ＳＩ）＋２０ｍ,ＺＷ型性决定,Ｚ为Ｖ型,Ｗ为ＳＩ型,Ｚ明显大于Ｗ;云南竹叶青２ｎ＝３６＝１６Ｍ（１２Ｖ／ＳＶ＋２ＳＶ／ＳＩ＋２ＳＩ）＋２ｍ,无异型性染本,对３种的核型及烙铁头属已知核型进行了比较分析,并对云南竹叶 相似文献
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Wilhelmus E. R. Rebholz 《Zoo biology》1992,11(4):291-295
Chromosomal variation within bird species has been rarely studied. Having studied three individuals, I report a difference in the length of Z-chromosomes in one male eagle owl (Bubo bubo) and use C- and R-banding to study the variation between these Z-chromosomes. Absence of non-centromeric heterochromatin in one Z-chromosome is the cause of the difference in length. The presence of two types of Z-chromosome in this eagle owl may reflect hybridization of animals from different subspecies, or might be caused by a spontaneous deletion of C-band positive DNA. © 1992 Wiley-Liss Inc. 相似文献