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1.
Previous phylogeographic studies of the warm-temperate zone in China focused on woody plants, but little attention was given to the climate-sensitive herbaceous plants. In this work, we implemented a phylogeographic survey on the perennial herb Achyranthes bidentata in China’s warm-temperate zone. The sequence variation of cpDNA and nDNA was examined across 209 individuals from 21 populations. A total of 11 chlorotypes and 26 ribotypes were identified. The cpDNA data showed weak population genetic differentiation and could not divide the 21 populations into different genetic groups. By contrast, the nDNA data revealed stronger genetic differentiation than cpDNA and could divide these populations into two genetic groups. The cpDNA and nDNA data both gave unambiguous signs of recent sudden population expansion. Based on the cpDNA and nDNA data, the estimated time of population expansion occurred at interglacial Marine Isotope Stage (MIS) 9 of the Penultimate Glaciation in China. The cpDNA and nDNA data suggested that the glaciation during this period deeply influenced the current distribution patterns and intraspecific divergence of A. bidentata. Our survey showed that A. bidentata tracked climatic oscillations by a large range of southward retreat into three main refugia during MIS 8, followed by the sudden northward expansion from these refugia during MIS 9.  相似文献   

2.
Saussurea involucrata (Asteraceae) is a medicinal and second-degree national priority endangered plant that is mainly distributed in the high latitude region of the western Tianshan Mountains. The population is fragmented and isolated, and extensive human impact merits a suitable and specific conservation strategy, which can be compiled based on the genetic diversity, population structure, and demographic history. Phylogeographic studies were conducted on a total of five natural populations and 150 individuals were sampled. Data from three cpDNA intergenic spacer regions (trnL-F, matK, and ndhF-rpl32) and nrDNA ITS sequences showed that twelve haplotypes in cpDNA and five haplotypes in nrDNA indicated high genetic diversity among populations sampled (H T?=?0.820 and 0.756) and within populations sampled (H S?=?0.792 and 0.721). Additionally, the high genetic diversity did not mirror genetic structure in either cpDNA (F ST?=?0.03153, G ST?>?N ST, p?<?0.05) or nrDNA (F ST?=?0.03666, meaningless G ST and N ST). Two groups (north and south) were determined for a SAMOVA analysis. Based on this analysis, the demographic history was conducted with a Bayesian Skyline Plot and Isolation with Migration analysis, which showed sustainable and stable extension without a marked bottleneck. Divergence time was indicated at c. 6.25 Mya (90%HPD: 15.30–0.22 Mya) in the Miocene, which is consistent with the formation of the Kelasu section of Tianshan. The southern populations in the Bayanbulak and Gonglu regions require additional attention and transplanting would be an effective way to restore rare cpDNA haplotypes, increase effective population size, and migration rate. Our results suggested that in situ conservation of S. involucrata in western Tianshan should be the main strategy for protection and recovery of the species.  相似文献   

3.
Eight pairs of chloroplast DNA (cpDNA) universal primers selected from 34 pairs were used to assess the genetic diversity of 132 pear accessions in Northern China. Among them, six amplified cpDNA fragments showed genetic diversity. A total of 24 variable sites, including 1 singleton variable site and 23 parsimony informative sites, as well as 21 insertion-deletion fragments, were obtained from the combined cpDNA sequences (5309–5535 bp). Two trnL-trnF-487 haplotypes, five trnL-trnF-413 haplotypes, five rbcL haplotypes, six trnS-psbC haplotypes, eight accD-psaI haplotypes and 12 rps16-trnQ haplotypes were identified among the individuals. Twenty-one haplotypes were identified based on the combined fragments. The values of nucleotide diversity (Pi), average number of nucleotide differences (k) and haplotype diversity (Hd) were 0.00070, 3.56408 and 0.7960, respectively. No statistical significance was detected in Tajima’s D test. Remarkably, the important cpDNA haplotypes and their representing accessions were identified clearly in this study. H_19 was considered as one of the ancient haplotypes and was a divergent centre. H_16 was the most common haplotype of the wild accessions. H_2 was the haplotype representing the most pear germplasm resources (46 cultivars and two wild Ussurian Pear accessions), followed by haplotype H_5 (30 cultivars, two wild Ussurian Pear accessions and four sand pears in outgroups) representing the cultivars ‘Dangshan Suli’ and ‘Yali’, which harbour the largest and the second largest cultivation areas in China. More importantly, this study demonstrated, for the first time, the supposed evolution routes of Pyrus based on cpDNA divergence in the background of pear phylogeny in Northern China.  相似文献   

4.
Phylogeographic patterns of Ammopiptanthus in northwestern China were examined with internal transcribed spacer (ITS) and three chloroplast intergenic spacers (trnH–psbA, trnL–trnF, and trnS–trnG). Two ITS genotypes (a–b) and 8 chloroplast haplotypes (A–H) were detected. Both ITS genotypes and chloroplast lineages were split in two geographic regions: western Xinjiang and the Alxa Desert. This lineage split was also supported by AMOVA analysis and the Mantel test. AMOVA showed that 89.81 % of variance in Ammopiptanthus occurred between the two geographic regions, and correlation between genetic distances and geographical distances was significant (r = 0.757, p < 0.0001). All populations in western Xinjiang shared haplotype A with high frequency, and range expansion was strongly supported by negative Fu’s FS value, and mismatch distribution analysis, whereas populations in the Alxa Desert had higher genetic diversity and structure. We speculate that the cold and dry climate during the early Quaternary fragmented habitats of the species, limiting gene flow between regions, and interglacial periods most likely led to the range expansion in western Xinjiang. The low genetic diversity of Ammopiptanthus indicate a significant extinction risk, and protective measures should be taken immediately.  相似文献   

5.
Hymenonema (Compositae, tribe Cichorieae) together with the genera Catananche, Gundelia, and Scolymus forms the subtribe Scolyminae. It is endemic to Greece and consists of two species, Hymenonema laconicum and Hymenonema graecum, which occur in the south Peloponnisos and central Aegean area, respectively. The present contribution aims at a phylogenetic reconstruction of evolutionary relationships among the 12 species of the subtribe, focusing on the temporal and spatial framework for its evolution. The phylogenetic relationships among the members of Scolyminae were inferred from molecular data based on the multi-copy region of the nrDNA internal transcribed spacers ITS1 and ITS2, two intergenic spacers of the cpDNA (trnL-trnF, rpl32-trnL), and one single-copy nuclear region (D10). The gene trees were reconstructed using Bayesian phylogenetic methods. All gene trees support the monophyly of Hymenonema and the sister-group relationship with the genus Scolymus. The further sister-group relationship of this group (HymenonemaScolymus) with Catananche is also supported by nrDNA and cpDNA analyses. Finally, a species tree (inferred in a Bayesian coalescent framework) was reconstructed and dates the divergence time between the two Hymenonema species to the Pleistocene (around 1.3 Ma ago). Maximum likelihood-based biogeographical reconstructions suggest a Miocene (pre-Messinian) differentiation of the subtribe on the northern Tethyan platform, followed by Miocene/Pliocene dispersal events to the western Mediterranean and North-African platforms and final, small-scale vicariance events within the genera in the Pleistocene.  相似文献   

6.
Many peninsulas in the temperate zone played an important role as refugia of various flora and fauna, and the southern Korean Peninsula also served as a refugium for many small mammals in East Asia during the Pleistocene. The Asian lesser white-toothed shrew, Crocidura shantungensis, is a widely distributed species in East Asia, and is an appropriate model organism for exploring the role of the Korean Peninsula as a refugium of small mammals. Here, we investigated phylogenetic relationships and genetic diversity based on the entire sequence of the mitochondrial cytochrome b gene (1140 bp). A Bayesian tree for 98 haplotypes detected in 228 C. shantungensis specimens from East Asia revealed the presence of three major groups with at least 5 subgroups. Most haplotypes were distributed according to their geographic proximity. Pairwise FST’s and analysis of molecular variance (AMOVA) revealed a high degree of genetic differentiation and variance among regions as well as among populations within region, implying little gene flow among local populations. Genetic evidence from South Korean islands, Jeju-do Island of South Korea, and Taiwan leads us to reject the hypothesis of recent population expansion. We observed unique island-type genetic characteristics consistent with geographic isolation and resultant genetic drift. Phylogeographic inference, together with estimates of genetic differentiation and diversity, suggest that the southern most part the Korean Peninsula, including offshore islands, played an important role as a refugium for C. shantungensis during the Pleistocene. However, the presence of several refugia on the mainland of northeast Asia is also proposed.  相似文献   

7.
This paper studies the phylogeography of Alnus alnobetula s. l. in the Asian part of the Russian range with the use of chloroplast DNA (cpDNA) sequences (intergenic spacers trnH-psbA, trnS-trnG, and psaA-trnS). Nine haplotypes were identified as a result of a combination of polymorphism of all sites in 241 plants in 20 populations of A. alnobetula. High interpopulation differentiation (GST = 0.914, NST = 0.928) and a significant phylogeographic structure (NST > GST, p < 0.05) were found. Reconstruction of genealogical relationships of green alder haplotypes revealed five highly divergent genetic lineages: one geographically widespread throughout Siberia and the Urals and several allopatric lines in the Far East of Russia, namely, the Chukotka Peninsula and the mouth of the Yana River, Magadan oblast, Primorye and the central part of Sakhalin Island, and the southern part of Sakhalin Island. Our data confirm that in the past the range of this species in the Far East was fragmented in several refugia that were isolated for a long time in various ice-free regions. This could have contributed to a high level of intraspecific polymorphism of green alder as a result of the divergence of endemic haplotypes, with almost non-overlapping distribution. However, the level of their molecular divergence does not correspond to the level of morphological differences.  相似文献   

8.
Two major modes of speciation, i.e., cladogenesis and anagenesis, have often been used to explain the generation of distinct plant diversity on oceanic islands. Anagenetic speciation is of particular interest to plant endemics on Ulleung Island, Korea because, of nearly 40 endemics, approximately 88% or even all endemic species are thought to be anagenetically derived. Despite its important role in Ulleung Island, the full scope of the anagenetic speciation and the genetic consequences of this speciation mode have been limited to a very few families (i.e., Apiaceae, Sapindaceae, and Ranunculaceae). Based on extensive sampling (a total of 322 individuals) and trnL-F cpDNA noncoding sequences, we conducted phylogenetic and haplotype network analyses for the species pair of Rubus crataegifolius (continental progenitor)-R. takesimensis (insular derivative). Rubus takesimensis on Ulleung Island is not a monophyletic group, suggesting at least two independent introductions from geographically and genetically divergent source populations. No significant reduction in cpDNA haplotype diversity and genetic differentiation in R. takesimensis are consistent with expectations from the anagenetically derived species. A further study based on comprehensive sampling and more variable molecular markers will shed light into the genetic consequences of anagenetic speciation in Rubus on Ulleung Island.  相似文献   

9.

Background

Phylogeographic analyses on the Western Euroasiatic Fagus taxa (F. orientalis, F. sylvatica, F. taurica and F. moesiaca) is available, however, the subdivision of Fagus spp. is unresolved and there is no consensus on the phylogeny and on the identification (both with morphological than molecular markers) of Fagus Eurasiatic taxa.For the first time molecular analyses of ancient pollen, dated at least 45,000 years ago, were used in combination with the phylogeny analysis on current species, to identify the Fagus spp. present during the Last Interglacial period in Italy.In this work we aim at testing if the trn L-trn F chloroplast DNA (cpDNA) region, that has been previously proved efficient in discriminating different Quercus taxa, can be employed in distinguishing the Fagus species and in identifying the ancient pollen.

Results

86 populations from 4 Western Euroasistic taxa were sampled, and sequenced for the trn L-trn F region to verify the efficiency of this cpDNA region in identifying the Fagus spp.. Furthermore, Fagus crenata (2 populations), Fagus grandifolia (2 populations), Fagus japonica, Fagus hayatae, Quercus species and Castanea species were analysed to better resolve the phylogenetic inference.Our results show that this cpDNA region harbour some informative sites that allow to infer relationships among the species within the Fagaceae family. In particular, few specific and fixed mutations were able to discriminate and identify all the different Fagus species.Considering a short fragment of 176 base pairs within the trn L intron, 2 transversions were found able in distinguishing the F. orientalis complex taxa (F. orientalis, F. taurica and F. moesiaca) from the remaining Fagus spp. (F. sylvatica, F. japonica, F. hayataea, F. crenata and F. grandifolia). This permits to analyse this fragment also in ancient samples, where DNA is usually highly degraded.The sequences data indicate that the DNA recovered from ancient pollen belongs to the F. orientalis complex since it displays the informative sites characteristic of this complex.

Conclusion

The ancient DNA sequences demonstrate for the first time that, in contrast to current knowledge based on palynological and macrofossil data, the F. orientalis complex was already present during the Tyrrhenian period in what is now the Venice lagoon (Italy).This is a new and important insight considering that nowadays West Europe is not the natural area of Fagus orientalis complex, and up to now nobody has hypothesized the presence during the Last Interglacial period of F. orientalis complex in Italy.
  相似文献   

10.
Vavilovia formosa is one of five genera in tribe Fabeae, (Fabaceae, Leguminosae) with close phylogenetic relationships to Pisum. It grows in subalpine and alpine levels in Armenia, Azerbaijan, Georgia, Iran, Iraq, Lebanon, Russia and Turkey and is recognized as an endangered and protected plant. This study was conducted to reveal its intraspecific variability, as well as to predict the past, extant and future species distribution range. We analysed 51 accessions with common phylogenetic markers (trnF-trnL, trnS-trnG, matK, rbcL, psbA-trnH and ITS). These represent in total up to 2551 bp of chloroplast and 664 bp of nuclear sequences per sample. Two populations from Turkey and Armenia were analysed for genetic diversity by AFLP. Leaf morphometry was conducted on 1457 leaflets from 43 specimens. Extracted bioclimatic parameters were used for niche-modelling approach. Analysis of cpDNA revealed two haplotypes, 12 samples from Armenia, Daghestan, Nakhichevan and Iran belonged to H1 group, while 39 samples of all Turkish and part of Armenian were in H2 group. The mean intrapopulation diversity based on AFLP was low (H E = 0.088) indicating limited outcrossing rate. A significantly positive correlation between geographical latitude and leaf area (\(\rho\) = 0.527, p < 0.05) was found. Niche modelling has shown temporal variation of predicted occurrence across the projected time periods. Vavilovia formosa has suffered a range reduction following climate warming after last glacial maximum, which classify this species as cold-adapted among the Fabeae species as well as a glacial relict.  相似文献   

11.
Subtropical East Asia harbours a large plant diversity that is often attributed to allopatric speciation in this topographically complex region characterized by a relative climate stability. Here, we use observations of Platycarya, a widespread subtropical Asian tree genus, to explore the consequences of past climate stability on species’ evolutionary history in subtropical China. This genus has a controversial taxonomy: while it is now prevailingly treated as monotypic, two species have been originally described, Platycarya strobilacea and P. longipes. Previous information from species distribution models, fossil pollen data and genetic data based on chloroplast DNA (cpDNA) were integrated with newly obtained genetic data from the two putative species. We used both cpDNA (psbA-trnH and trnL-F intergenic spacers, including a partial trnL gene sequence) and nuclear markers. The latter included sequences of the internal transcribed spacer region (ITS1–5.8S–ITS2) of the nuclear ribosomal DNA and random genomic single nucleotide polymorphisms. Using these nuclear genetic markers, we found interspecific genetic divergence fitting with the ‘two species’ scenario and geographically structured intraspecific variation. Using cpDNA markers, we also found geographically structured intraspecific variation. Despite deep inter- and intraspecific genetic divergence, we detected genetic admixture in southwest China. Overall, our findings of genetic divergence within Platycarya support the hypothesis of allopatric speciation. However, episodes of population interconnection were identified, at least in southwest China, suggesting that the genus has had a dynamic population history.  相似文献   

12.
Cycas debaoensis is a critically endangered cycad species endemic to China. This species is found on two kinds of habitats according to the edaphic differences, sand and karst. A previous chloroplast DNA (cpDNA) study indicated that C. debaoensis had low genetic variation within populations and high genetic differentiation among populations. Because maternally inherited cpDNA does not fully characterize genetic structure of the species, we screened seven low-copy nuclear genes and 17 nuclear microsatellite loci to detect the nuclear genetic diversity, differentiation, and the population structure of C. debaoensis. The nuclear genes revealed higher level of genetic diversity. There were both the same and region-specific haplotypes or alleles between the karst and sand regions. Nuclear gene flow among all the populations was much greater than that of cpDNA, which indicated that pollen-mediated gene flow was much greater than seed-mediated gene flow. This promoted low nuclear genetic differentiation among populations of C. debaoensis. The study suggests that both genetic and anthropogenic disturbances have resulted in the critically endangered status of C. debaoensis.  相似文献   

13.
Polyploidization has long been recognized as one of the most important driving forces of plant evolution. Aconitum subgenus Lycoctonum (Ranunculaceae) has a wide distribution range and well-known background of polyploidy, thereby providing a potentially valuable model to explore polyploid origin and evolutionary history. However, the phylogeny of subg. Lycoctonum has not yet been completely resolved. In the current study, 29 species including diploid, tetraploid and hexaploid species were sampled in subg. Lycoctonum. Using four cpDNA regions (ndhF-trnL, psbA-trnH, psbD-trnT and trnT-L) and two nrDNA regions (internal transcribed spacer, ITS, and external transcribed spacer, ETS), phylogenetic relationship was first reconstructed for the polyploid species within subg. Lycoctonum. In combination with nuclear diversification rate estimation, cpDNA haplotype network, ancestral area reconstruction as well as morphological and karyotypic evidence, potential origin and divergence time were further assessed among the polyploid species. Hybridization was inferred for A. angustius and A. finetianum was suggested to be the potential maternal progenitor, due to their close phylogenetic relationship, highly similar morphologies and overlapping distribution range. Local origin was inferred for tetraploids in the Hengduan Mountains (HDM) with eight groups of chromosomes of four homeologous, which diverged approximately 3.00 Ma in the same period of the orogeny of the HDM. The hexaploid A. apetalum was inferred to suffer from geographical isolation due to the formation of the Qinghai–Tibetan Plateau (QTP) and the HDM. Hybridization and heterogeneous habitats in the HDM were suggested to play an important role in the polyploidization in subg. Lycoctonum.  相似文献   

14.
The Caucasus region is one of the 25 global biodiversity hotspots and constitutes a shelter area for Neogene relict species as well as a center of ongoing radiation. In order to elucidate the taxonomic identity, divergence patterns, and evolutionary history of the largely widespread Georgian durmast oak (Quercus petraea subsp. iberica), we examined leaf morphology and chloroplast DNA (cpDNA) (trnH-psbA, trnK-matK) sequence variation across its South Caucasian range. Six other oak taxa distributed throughout Georgia were included in the dataset and used for comparison. Evidence for differentiation in both sets of traits was found. Populations represented by different taxa from ecologically equivalent areas showed common morphological features and genetic structures. Molecular analysis clearly indicated the presence of two major haplotype lineages (West Caucasian vs. East Caucasian zonation type) and suggested a maternal lineage diversification of Q. petraea subsp. iberica in the Late Miocene, as a likely result of complex patterns associated with major orogenic and climatic changes. The Quaternary glacial oscillations resulted in a number of less common, derived haplotypes. Based on mismatch distribution analysis and neutrality tests, we found no evidence of demographic expansion for the populations from the West and East Caucasian zonation types. The two Caucasian provinces therefore acted as important shelter/diversification areas and as a lineage crossroad for the Georgian oaks. Close intra- and interspecific cpDNA relationships shared with other oaks from bordering countries support the relevant role played by the Colchis region as a primary refugium for the European temperate forest species.  相似文献   

15.
16.
In this study, we assessed geographic patterns of genetic variations in nuclear and chloroplast genomes of two related native oaks in Japan, Quercus aliena and Q. serrata, in order to facilitate development of genetic guidelines for transfer of planting stocks for each species. A total of 12 populations of Q. aliena and 44 populations of Q. serrata were analyzed in this study. Genotyping of nuclear microsatellites in Q. aliena was done with only nine populations (n = 212) due to limited numbers of individuals in two populations, while all 12 populations (n = 89) were used in sequencing chloroplast DNA (cpDNA). In Q. serrata, 43 populations (n = 1032) were genotyped by nuclear microsatellite markers, while cpDNA of 44 populations (n = 350) was sequenced. As anticipated, geographic patterns detected in the variations of Q. aliena’s nuclear genome and its chloroplast haplotype distribution clearly distinguished northern and southern groups of populations. However, those of Q. serrata were inconsistent. The geographic distribution of its chloroplast haplotypes tends to show the predicted differentiation between northern and southern lineages, but geographic signals in the genetic structure of its nuclear microsatellites are weak. Therefore, treating northern and southern regions of Japan as genetically distinct transferrable zones for planting stocks is highly warranted for Q. aliena. For Q. serrata, the strong NE-SW geographic structure of cpDNA should be considered.  相似文献   

17.
The uplift of mountains and climatic oscillations are important for understanding of the demographic history and genetic structure of species. We investigated the biogeographic history of the boreal tree species Ulmus lamellosa (Ulmaceae) in China, by using a combined phylogeographic and paleodistribution modeling approach. In this study, 14 populations of endangered U. lamellosa were analyzed by using chloroplast DNA (cpDNA) sequences. A high level of genetic differentiation (Φ ST = 86.22%) among populations with a significant phylogeographic pattern (N ST > G ST, P < 0.05) was found in U. lamellosa. Ten haplotypes were detected by combining chloroplast DNA data, and haplotype 3 (H3) was found to be common and widespread. The intraspecific divergence of all U. lamellosa cpDNA haplotypes (9.27 Ma; 95% HPD 5.17–13.33 Ma) most probably began in the late Miocene. The pairwise difference among haplotypes and neutrality tests (Tajima’s D and Fu’s Fs statistic) indicated that populations of U. lamellosa, except group I, have not experienced recent sudden expansions. Multiple refuge areas were identified across the entire distribution ranges of U. lamellosa. The low level of gene flow (Nm = 0.14) among populations may have resulted from isolation resulting from distance and complex topography during climatic oscillations; this isolation was probably the major process that shaped the present distribution of haplotypes. These results support the hypothesis that U. lamellosa persisted in situ during glaciations and occupied multiple localized glacial refugia, contrary to the hypotheses of large-scale range contraction and long-distance southward migration.  相似文献   

18.
A key to understanding the origin and identity of young species lays on the knowledge of the Quaternary climatic oscillations’ effect on gene flow and vicariance. Even though the effect of climatic fluctuations is relatively well understood for southern hemisphere plant species, little is known about their effect on the evolutionary histories of species from mainland and islands. Thus, we investigated whether Quaternary climate-driven fluctuations translated into lineage divergence and speciation, followed or not by climatic niche differentiation, in two allopatric plant species, Calceolaria uniflora and C. fothergillii from Patagonia and Malvinas/Falkland islands, respectively. We sampled the range of both species, and sequenced two chloroplastic (cpDNA; trnS–trnG and trnH–psbA), and one single copy “anonymous” non-coding nuclear region (nDNA). We performed phylogeographic and dating analyses, and adjusted spatio-temporal diffusion models. We complemented molecular evidence with climatic niche differentiation analyses and species paleo-distribution projections. A species coalescent reconstruction based on multi-locus data retrieved both species as monophyletic. Estimates from cpDNA indicated the species diverged during the Great Patagonian Glaciation. Chloroplast and nuclear DNA showed east–west distribution of the main genetic groups but with contrasting spatial genetic diversity. The spatio-temporal diffusion analyses showed that between 1–0.8 Mya and 570 Kya the lineage leading to C. fothergillii diverged from C. uniflora and arrived to the islands. Climatic niche projections hindcasted range expansions during glaciations, and contractions during the interglacial periods. Comparisons of climatic niches between the two study species indicated that temperature variables show evidence of niche conservatism while precipitation regimes supported niche divergence, even when considering the background environmental divergence. Our study indicates that glacial fluctuations affected the mainland/islands connections favouring speciation mediated not only by isolation, but also by climatic niche differentiation.  相似文献   

19.
Capitulate inflorescence is a specific, strongly adaptive and rare feature in the genus Campanula. We studied morphologically eight capitulate Campanula taxa from the Balkans (1537 individuals/52 populations) and one more species from Caucasus at the molecular level (using chloroplast markers trnGUCC-trnSGCU and psbA-trnH, 130 individuals/58 populations) to assess their relations and evolutionary histories. Although all studied taxa were well circumscribed at both the morphological and molecular levels (except morphologically distinct but genetically invariable C. moesiaca which acquired its single haplotype via past cytoplasmic introgression from C. cervicaria), their relations inferred from the two datasets were incongruent possibly due to the homoplasy of morphological characters frequently reported in Campanula. Interspecific hybridization and introgression affected majority of studied species and may be more common in Campanula than previously thought. These processes, along with incomplete lineage sorting and retention of ancestral polymorphisms, hampered our phylogenetic reconstructions and prevented us to fully resolve species relations, and to support monophyletic origin of capitulate Campanula species. Nonetheless, several cryptic taxa were delineated, and C. daucoides was described as a new capitulate Campanula species. Different evolutionary histories and multiple glacial refugia were inferred for all species represented by multiple samples (except C. moesiaca). According to our dating, their speciation was in most cases triggered by various geo-historic events such as the uplift of the Alpide belt, Messinian Salinity Crisis, or desiccation of the Pannonian Sea/Pliocene Lakes from the central Balkans, while their further diversification was mainly driven by the onset of the Quaternary and cycles of glacials/interglacials.  相似文献   

20.
Chikanda is a traditional dish made with wild-harvested ground orchid tubers belonging to three orchidioid genera, Disa, Satyrium and Habenaria, all of which are CITES appendix II-listed. Identification of collected orchid tubers is very difficult and documentation of constituent species in prepared chikanda has hitherto been impossible. Here amplicon metabarcoding was used in samples of six prepared chikanda cakes to study genetic sequence diversity and species diversity in this product. Molecular operational taxonomic unit identification using similarity-matching reveals that species of all three genera were present in the chikanda samples studied. Disa was present in all of the samples, Satyrium in five out of six and Habenaria in one of the samples, as well as a number of other plants. The fact that each sample contained orchids and the presence of a wide variety of species from all genera in this traditional dish raise serious concerns about the sustainability of this trade and the future of wild orchid populations in the main harvest areas. This proof-of-concept study shows that Ion-Torrent PGM is a cost-effective scalable platform for metabarcoding using the relatively long nrITS1 and nrITS2 regions. Furthermore, nrITS metabarcoding can be successfully used for the detection of specific ingredients in a highly-processed food product at genus level, and this makes it a useful tool in the detection of possible conservation issues arising from commercialized trade or processed plant products.  相似文献   

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