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1.
Zusammenfassung Arnebia purpurascens (A.Rich.)Baker wird ausführlicher beschrieben, als dies in der bisherigen Literatur geschah.Arnebia euchroma (Royle) I. M.Johnst., die zur UntergattungMacrotomia (DC. exMeisn.) H.Riedl, stat. nov., zu rechnen ist, wird in drei Unterarten geteilt, nämlich ssp.euchroma, ssp.grandis H.Riedl, ssp. n. aus Südwestpersien und ssp.caespitosa Rech. f. etRiedl, ssp. n. aus Ost-Afghanistan und Chitral.Durchgeführt mit Unterstützung durch National Science Foundation Grant G 16325.  相似文献   

2.
An electrophoretic analysis of histone H1 of Aegilops tauschii was carried out using the collection of 303 accessions (156 of ssp. tauschii and 147 of ssp. stangulata) representing all the species range. Three, four and six allelic variants were found for Hst1, Hst2 and Hst3 locus, respectively. The level of histone H1 allelic variability in ssp. strangulata was considerably higher than in ssp. tauschii. Expected heterozygosity (HE) for the loci Hst1, Hst2 and Hst3 made up 0.066, 0.484 and 0.224 respectively in ssp. strangulata vs. 0.024, 0.051 and 0.214 in ssp. tauschii. Besides the most common haplotype, Hst1 1000, Hst2 1000, Hst3 1000, five other haplotypes with frequencies of occurrence higher than 0.02 were found in ssp. strangulata, and only one such haplotype—in ssp. tauschii. The most part of histone H1 variation in ssp. tauschii was in the western part of the area. In ssp. strangulata, the alleles Hst2 988 and Hst2 973 were found only in Caucasia, and the allele Hst1 1043—only in Precaspian Iran and south-eastern Azerbaijan. Histone H1 variation patterns in Ae. tauschii are very similar to those of non-coding sequences of chloroplast DNA. Therefore, histone H1 allelic variation in this species seems to be mostly neutral. Nevertheless, the evidences were pointed out, revealing that some part of variation at Hst2 locus in ssp. strangulata could be adaptive. It seems that Hst2 1026 allele is disadvantageous in western Precaspian Iran, the region with the high annual rainfall, and being eliminated by natural selection.  相似文献   

3.
Taxonomic complexity may be associated with migration history and polyploidy. We used plastid and nuclear DNA markers to investigate the evolutionary history of the systematically challenging Dactylorhiza maculata polyploid complex. A total of 1833 individuals from 298 populations from throughout Europe were analysed. We found that gene flow was limited between the two major taxa, diploid ssp. fuchsii (including ssp. saccifera) and tetraploid ssp. maculata. A minimum of three autotetraploid lineages were discerned: (1) southern/western ssp. maculata; (2) northern/eastern ssp. maculata; and (3) Central European ssp. fuchsii. The two ssp. maculata lineages, which probably pre‐date the last glaciation, form a contact zone with high genetic diversity in central Scandinavia. Intermediate plastid haplotypes in the contact zone hint at recombination. Central Europe may have been a source area for the postglacial migration for the southern/western lineage of ssp. maculata, as well as for ssp. fuchsii. The northern/eastern lineage of ssp. maculata may have survived the LGM in central Russia west of the Urals. The tetraploid lineage of ssp. fuchsii is indistinguishable from diploid ssp. fuchsii, and is probably of postglacial origin. The Mediterranean region and the Caucasus have not contributed to the northward migration of either ssp. fuchsii or ssp. maculata. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 503–525.  相似文献   

4.
This study investigates the genetic differentiation within the Central European Armeria maritima (Mill.) Willd. complex with special reference to the metallicolous populations using AFLP markers. Our sampling comprised all metallicolous (ssp. halleri, hornburgensis, bottendorfensis, eifeliaca, calaminaria), and non-metallicolous taxa (ssp. maritima, elongata, alpina). Geographical and genetic distances between populations were moderately positively correlated. Genetic variability of metallicolous and non-metallicolous populations was not significantly different. Lowland populations were clearly differentiated from the alpine populations. Within the lowland group metallicolous and non-metallicolous populations were not genetically differentiated. All lowland populations show a regional differentiation and close relationships to ssp. elongata. Thus, the metallicolous taxa should not be maintained as subspecies. Likewise, their treatment as varieties of a ssp. halleri s.l. is critical because this taxon cannot be consistently characterized throughout its geographical range and may be an artefact itself. If a taxonomical recognition should be considered necessary it is advisable to treat the microendemics as varieties of ssp. elongata.  相似文献   

5.
6.
The essential‐oil variability in seven native populations belonging to different infraspecific taxa of Pinus nigra (ssp. nigra, var. gocensis, ssp. pallasiana, and var. banatica) growing wild in Serbia was analyzed. In the needles of 195 trees from seven populations, 58 essential‐oil components were identified. The major components were α‐pinene (43.6%) and germacrene D (29.8%), comprising together 73.4% of the total oil composition. Based on the average chemical profile of the main terpene components (with contents >5%), the studied populations were found to be the most similar to populations from central Italy and Greece (ssp. nigra). Cluster analysis showed the division of the populations into three principal groups: the first group consisted of Populations I, II, III, IV, and V (considered as ssp. nigra group), the second of Population VI (ssp. pallasiana group), and the third of Population VII, which had the most distinct oil composition (ssp. banatica group). The taxonomic implications of the essential‐oil profiles of the investigated taxa of this very complex species are discussed.  相似文献   

7.
The monophyletic Nasa ranunculifolia group (Nasa ser. Grandiflorae pro parte) is revised on the basis of extensive field studies and a revision of copious herbarium material. All species of this group are from the high Andes of Peru and Ecuador (mostly 3000–4300 m). The overall degree of morphological divergence is much lower than in other groups of Nasa and many of the various local ‘races’ are best recognized as ecogeographically isolated subspecies. Thus, six species and 13 subspecies are recognized on the basis of differences in leaf and floral morphology, growth habit, life history and distribution. Nasa ranunculifolia, N. macrantha, N. cymbopetala and N. macrorrhiza are united as subspecies under N. ranunculifolia. An additional five subspecies of N. ranunculifolia are newly described (ssp. pamparomasii, ssp. guzmangoensis, ssp. bolivarensis, ssp. patazensis and ssp. huanucoensis). Nasa rugosa is subdivided into four subspecies, three of them new (ssp. llaqtacochaensis, ssp. gracilipes and ssp. pygmaea). Nasa tulipadiaboli sp. nov. and N. basilica sp. nov. are described as new species. Eight taxa (seven subspecies and one species) are endemic to the Amotape–Huancabamba Zone, and seven of them (six subspecies and one species) are new to science. Only a single species ranges into the Amotape–Huancabamba Zone from the south, underscoring the high levels of endemism (and taxonomic novelty) in this area. Illustrations, distribution maps, a key and diagnoses are given for all taxa recognized. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 47–93.  相似文献   

8.
Forest trees frequently form species complexes, complicating taxonomic classification and gene pool management. This is certainly the case in Eucalyptus, and well exemplified by the Eucalyptus globulus complex. This ecologically and economically significant complex comprises four taxa (sspp. bicostata, globulus, maidenii, pseudoglobulus) that are geographically and morphologically distinct, but linked by extensive “intergrade” populations. To resolve their genetic affinities, nine microsatellites were used to genotype 1200 trees from throughout the natural range of the complex in Australia, representing 33 morphological core and intergrade populations. There was significant spatial genetic structure (FST = 0.10), but variation was continuous. High genetic diversity in southern ssp. maidenii indicates that this region is the center of origin. Genetic diversity decreases and population differentiation increases with distance from this area, suggesting that drift is a major evolutionary process. Many of the intergrade populations, along with other populations morphologically classified as ssp. pseudoglobulus or ssp. globulus, belong to a “cryptic genetic entity” that is genetically and geographically intermediate between core ssp. bicostata, ssp. maidenii, and ssp. globulus. Geography, rather than morphology, therefore, is the best predictor of overall genetic affinities within the complex and should be used to classify germplasm into management units for conservation and breeding purposes.  相似文献   

9.
Using microsatellite (SSR) markers, the genetic diversity and genetic relationships among 48 Triticum turgidum L. accessions, including 30 Triticum turgidum L. ssp. turgidum, 7 Triticum turgidum L. ssp. durum, 4 Triticum turgidum L. ssp. carthlicum, 3 Triticum turgidum L. ssp. paleocolchicum, 2 Triticum turgidum L. ssp. turanicum, and 2 Triticum turgidum L. ssp. polonicum accessions, were investigated. A total of 97 alleles were detected at 16 SSR loci. At each locus, the number of alleles ranged from two to fourteen, with an average of 6.1. The genetic similarity (GS) value ranged from 0.20 to 0.92, with the mean of 0.59. In cluster analysis, it was found the 48 Triticum turgidum L. accessions could be distinguished easily by SSR markers, whereas the six subspecies taxonomic entities of T. turgidum L. could not differentiate with each other, indicating that the morphological differences present among the six subspecies could not be reflected by the SSR markers. These results suggested that SSR markers had superiority in detecting the genetic diversity of T. turgidum L., while they were not good for studies of the phylogenic relationships among the subspecies of T. turgidum L. The text was submitted by the authors in English.  相似文献   

10.
The world’s oldest and largest Medicago truncatula collection is housed at the South Australian Research and Development Institute (SARDI). We used six simple sequence repeat (SSR) loci to analyse the genetic diversity and relationships between randomly selected individuals from 192 accessions in the core collection. M. truncatula is composed of three subspecies (ssp.): ssp. truncatula, ssp. longeaculeata, and ssp. tricycla. Analysis at the level of six SSR loci supports the concept of ssp. tricycla, all the samples of which showed unique alleles at two loci. Contingency Chi-squared tests were significant between ssp. tricycla and ssp. truncatula at four loci, suggesting a barrier to gene flow between these subspecies. In accessions defined as ssp. longeaculeata, no unique allelic distribution or diagnostic sizes were observed, suggesting this apparent ssp. is a morphological variant of ssp. truncatula. The data also suggest M. truncatula that exhibits unusually wide genotype dispersal throughout its native Mediterranean region, possibly due to animal and trade-related movements. Our results showed the collection to be highly diverse, exhibiting an average of 25 SSR alleles per locus, with over 90% of individuals showing discrete genotypes. The rich diversity of the SARDI collection provides an invaluable resource for studying natural allelic variation of M. truncatula. To efficiently exploit the variation in the SARDI collection, we have defined a subset of accessions (n=61) that maximises the diversity.  相似文献   

11.
Two subspecies of Barbarea vulgaris are taxonomically recognized as ssp. vulgaris and ssp. arcuata. In addition, two types of Barbarea vulgaris ssp. arcuata occurs in Denmark. The G‐type is resistant to an herbivorous flea beetle (Phyllotreta nemorum) whereas the P‐type is susceptible. A previous study suggested that the P‐type evolved by a loss of resistance from a resistant progenitor. We analyzed the genetic relatedness among eight Barbarea taxa: B. vulgaris spp. vulgaris, B. vulgaris ssp. arcuata G‐ and P‐types, hybrids between the types, B. verna, B. intermedia, B. stricta, B. orthoceras and B. australis, using AFLP and SSR markers. A clear distinction between the G‐ and P‐types was revealed. Both were distinct from B. vulgaris ssp. vulgaris, the G‐type less so than the P‐type. Barbarea verna and B. intermedia formed unambiguous clusters, whereas the remaining taxa produced less discrete groupings. Possible evolutionary scenarios for flea‐beetle resistance and susceptibility are discussed, including lineage sorting from a polymorphic ancestral population, and de novo loss of resistance in the P‐type of B. vulgaris ssp. arcuata.  相似文献   

12.
Nineteen microsatellite markers were developed from Tetratheca paynterae ssp. paynterae, a rare and endangered, leafless, perennial shrub. Twelve loci were polymorphic in T. paynterae ssp. paynterae with two to 14 alleles per locus and mean expected heterozygosity of 0.62. Primer pairs were tested on four other Tetratheca species from ironstone ranges in southern Western Australia. Ten loci were polymorphic in T. paynterae ssp. cremnobata and T. aphylla ssp. aphylla, three in T. harperi and four in T. erubescens. The level of polymorphism was adequate for studies of genetic structure and mating systems in three of the five taxa.  相似文献   

13.
Zusammenfassung Als zweite Vorarbeit für die Monographie derPittosporum-Arten von Madagaskar wurdenP. senacia Pütt.,P. verticillatum Boj. undP. ochrosiaefolium Boj. hinsichtlich ihrer Variabilität und Verbreitung genauer untersucht und wie folgt neu gegliedert:P. senacia ssp.senacia (Mauritius und Réunion), ssp.coursii (N.-Madagaskar), ssp.pervillei (N.-Madagaskar und Réunion), ssp.wrightii (Seychellen);P. verticillatum ssp.verticillatum (O.- und C.-Madagaskar) mit der Varietäten *intermedium, *microphyllum und *tsaratananae, sowie die nicht weiter gegliederte ssp.pangalanense (O.-Madagaskar);P. ochrosiaefolium (O.- und C.-Madagaskar) mit den Varietätenochrosiaefoliwm, madagascariense undamygdaloides. Außer den mit Sternchen bezeichneten Untersippen wurdeP. balfourii aus der Insel Rodriguez neu beschrieben. Den Abschluß bildet eine Übersicht aller madagassischenPittosporum-Sippen und ein Literaturnachtrag.  相似文献   

14.
 More than 100 accessions of Hordeum marinum ssp. marinum, ssp. gussoneanum 2x and ssp. gussoneanum 4x were studied by analyzing the nuclear DNA homologous to the chloroplast translation elongation factor. PCR amplification using the locus-specific primers generated a 932 bp fragment from ssp. marinum, a 915 bp fragment from ssp. gussoneanum 2x, and 915 bp and 931 bp fragments from ssp. gussoneanum 4x. Sequencing of the entire DNAs showed that the 915-bp fragments of diploids and tetraploids are identical, indicating that the diploid probably is the immediate donor of the 915-bp fragment of tetraploids. Although the donor of the 931-bp fragment was not determined, phylogenetic analysis of the data showed that the clade of the 931-bp fragment was included in the H. marinum complex. A MspI site was diagnostic to distinguish ssp. marinum into two clades with disjunct distributions, the Iberian Peninsula (type 2) and other regions (type 1). Nucleotide variation was revealed in the type 2 accessions but all the other clades were highly uniform. Received January 3, 1999 Accepted January 24, 2001  相似文献   

15.
Two zinc violets, the yellow form of the Aachen–Liège area and the blue morph of Blankenrode in western Westphalia, have very restricted occurrence on heavy metal waste heaps. Their taxonomic affinities have not been finally resolved. The flower micromorphological analysis presented here indicates that both zinc violets are closely related to the alpine Viola lutea, in line with our earlier published molecular data, but not with the conclusions of other authors. The zinc violets are classed at the rank of subspecies as V. lutea: ssp. calaminaria for the yellow zinc violet and ssp. westfalica for its blue counterpart. Although the violets examined (V. lutea, V. lutea ssp. calaminaria, V. lutea ssp. westfalica) are closely related, there is no evidence that V. lutea ssp. westfalica is a descendent of V. tricolor. Here we provide the most detailed information on generative organ structure in the four violets studied.  相似文献   

16.
17.
 Taxa of the Viola alba complex were investigated using allozymes and morphometry. A taxonomic revision is presented. A wide delimitation of V. alba with only three morphological and geographical subspecies is suggested: (1) ssp. dehnhardtii distributed in the Mediterranean eastwards to Turkey; (2) ssp. alba flanking ssp. dehnhardtii in the north and east; and (3) ssp. cretica endemic to Crete. Ssp. cretica, up to now treated as a separate species, is particularly close to ssp. dehnhardtii. Viola cadevallii (NW Mediterranean) is included in the synonymy of ssp. dehnhardtii. Ssp. scotophylla (S Europe), ssp. thessala (Balkan), V. armena (Turkey), and V. besseri (Caucasus) are reduced to synonyms of V. alba ssp. alba. Viola pentelica (Greece) might represent transitional forms between ssp. alba and ssp. dehnhardtii. Glacial refugia for ssp. alba are suggested from the eastern Mediterranean via Turkey to the Caucasus, for ssp. dehnhardtii in the Mediterranean area in general, and for ssp. cretica in Crete. A key to the subspecies is provided. Taxonomic recombination: Viola alba Bess. ssp. cretica (Boiss. & Heldr.) Marcussen, comb. nov. Received June 17, 2002; accepted November 27, 2002 Published online: March 20, 2003  相似文献   

18.
Ten microsatellite loci were isolated from the African ant‐plant Leonardoxa africana (Fabaceae: Caesalpinioideae). They differentiate the two most divergent subspecies of this polytypic complex, L. a. africana and L. a. gracilicaulis, showing promise for the study of gene flow. In each of these two subspecies, high levels of within‐population variation were observed, with a number of alleles ranging from one to 10 in ssp. africana and from one to 7 in ssp. gracilicaulis, and heterozygosity from 0 to 0.933 in ssp. africana and to 0.867 in ssp. gracilicaulis. All loci amplified successfully in the two other subspecies of L. africana.  相似文献   

19.
Thirty two species ofFimbristylis (Cyperaceae) thus far documented from Ceylon are taxonomically discussed with particular emphasis on the collections of Thwaites and Trimen. In addition to the synonymy and critical citation of specimens, a key is provided to differentiate these species.Fimbristylis tenera is newly added to the Ceylon flora. The new combinations proposed are:F. dichotoma ssp.glauca, F. fusca ssp.fulvescens, F. aestivalis ssp.major, andF. tenera ssp.oxylepis.  相似文献   

20.
Homoploid hybrid plant species are rare, and the mechanisms of their speciation are largely unknown, especially for homoploid hybrid tree species. Two contrasting hypotheses have been proposed to explain the origin of Hippophae goniocarpa: (1) it is a diploid hybrid originating from H. rhamnoides ssp. sinensis × H. neurocarpa ssp. neurocarpa, and (2) it originated via marginal differentiation from H. rhamnoides ssp. sinensis. Regardless of which of these hypotheses is true (if either), previous studies have suggested that H. rhamnoides ssp. sinensis is the only maternal donor for this hybrid species. In this study, we aim to elucidate the maternal composition of H. goniocarpa and to test the two hypotheses. For this purpose, we sequenced the maternal chloroplast DNA trnL‐F region of 75 individuals representing H. goniocarpa, H. rhamnoides ssp. sinensis, and H. neurocarpa ssp. neurocarpa in two co‐occurring sites of the taxa. Seven haplotypes were identified from three taxonomic units, and their phylogenetic relationships were further constructed by means of maximum parsimony, maximum likelihood, and network analyses. These seven haplotypes clustered into two distinct, highly divergent lineages. Two haplotypes from one lineage were found in H. rhamnoides ssp. sinensis, and five (representing the other lineage) in H. neurocarpa ssp. neurocarpa. Hippophae goniocarpa shared four common haplotypes from both lineages, but the haplotypes detected from the two populations differed to some extent, and in each case were identical to local haplotypes of the putative parental species. Thus, both H. rhamnoides ssp. sinensis and H. neurocarpa ssp. neurocarpa appear to have together contributed to the maternal establishment of H. goniocarpa. These results clearly demonstrate that the marginal origin hypothesis should be rejected, and support the hybrid origin hypothesis. Hippophae goniocarpa exhibits a sympatric distribution with its two parent species, without occupying new niches or displaying complete ecological isolation. However, this species has effectively developed reproductive isolation from its sympatric parent species. Our preliminary results suggest that H. goniocarpa may provide a useful model system for studying diploid hybrid speciation in trees. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 156 , 111–118.  相似文献   

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