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1.
The fresh leaves of Hillebrandia sandwicensis and 126 Begonia taxa were chemotaxonomically surveyed for flavonoids. Of their taxa, H. sandwicensis and 119 species, one variety and three hybrids were analyzed for flavonoids for the first time. Ten flavonols and eleven C-glycosylflavones were isolated and characterized as quercetin 3-O-rutinoside (1), kaempferol 3-O-rutinoside (2), isorhamnetin 3-O-rutinoside (3), quercetin 3-O-glucoside (4), quercetin 3-methyl ether 7-O-rhamnosylglucoside (5), quercetin 3,3'-dimethyl ether 7-O-rhamnosylglucoside (6), quercetin glycoside (13), quercetin glycoside (acylated) (14), kaempferol glycoside (17) and quercetin 3-O-rhamnoside (18) as flavonols, and isovitexin (7), vitexin (8), isoorientin (9), orientin (10), luteolin 6-C-pentoside (11), luteolin 8-C-pentoside (12), schaftoside (15), isoschaftoside (16), chrysoeriol 6,8-di-C-pentoside (19), apigenin 6,8-di-C-arabinoside (20) and isovitexin 2''-O-glucoside (21) as C-glycosylflavones. Quercetin 3-O-rutinoside (1) alone was isolated from H. sandwicensis endemic to Hawaii. Major flavonoids of almost Begonia species was also 1. Begonia species were divided into two chemotypes, i.e. flavonol containing type and C-glycosylflavone containing type. Of 14 section of the Begonia, almost species of many section, i.e. sect. Augustia, Coelocentrum, Doratometra, Leprosae, Loasibegonia, Monopteron and Ruizoperonia, were flavonol types. On the other hand, C-glycosyflavone type was comparatively most in sect. Platycentrum.  相似文献   

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世界秋海棠属侧膜组植物新资料   总被引:2,自引:0,他引:2  
记述了秋海棠属侧膜组11新种,即星果草叶秋海棠(BegoniaasteropyrifoliaY.M.ShuietW.H.Chen)、耳托秋海棠(B.auritistipulaY.M.ShuietW.H.Chen)、桂南秋海棠(B.austroguangxiensisY.M.ShuietW.H.Chen)、水晶秋海棠(B.crystallinaY.M.ShuietW.H.Chen)、须苞秋海棠(B.fimbribracteataY.M.ShuietW.H.Chen)、巨叶秋海棠(B.gigaphyllaY.M.ShuietW.H.Chen)、黄氏秋海棠(B.huangiiY.M.ShuietW.H.Chen)、长柱秋海棠(B.longistylaY.M.ShuietW.H.Chen)、扁果秋海棠(B.platycarpaY.M.ShuietW.H.Chen)、喙果秋海棠(B.rhynchocarpaY.M.ShuietW.H.Chen)、多变秋海棠(B.variifoliaY.M.ShuietW.H.Chen);并报道了3新变种及1新名称,即疏毛越南秋海棠(B.boniiGagnep.var.remotisetulosaY.M.ShuietW.H.Chen)、密毛龙州秋海棠(B.morseiIrmsch.var.myriotrichaY.M.ShuietW.H.Chen)、簇毛伞叶秋海棠(B.umbr-aculifoliaY.WanetB.N.Changvar.flocculosaY.M.ShuietW.H.Chen)及彩纹秋海棠(B.variegataY.M.ShuietW.H.Chen)。  相似文献   

4.
 The karyomorphology of all 14 species of Taiwanese Begonia was investigated to elucidate their chromosome features and chromosomal evolution. Among all species investigated, differences in chromosome features are found in: (1) chromosome number 2n = 22, 26, 36, 38, 52, 60, 64, 82, and (2) frequencies of chromosomes with secondary, tertiary, and/or small constrictions of polyploids, ranging from 23% to 63%, which is higher than the expected value of about 9%. It is suggested that after polyploidization from the diploid species (i.e., 2n = 22 and frequencies of chromosomes with secondary, tertiary, and/or small constrictions of polyploids of about 9%), chromosome translocations occurred, followed by a decrease in chromosome number, and subsequently stabilized genomes were formed in various species in Taiwan. The karyomorphological evidence also suggested that the chromosome morphology has evolved in parallel in the begonias belonging to different sections in Taiwan. The variation in chromosomal features is more complex than the variation in floral and fruit morphologies. Karyomorphological data also supports the recognition of five new species in Taiwan: Begonia bouffordii, B. chuyunshanensis, B. pinglinensis, B. tengchiana, and B. wutaiana. Based on detailed karyomorphological analyses, the taxonomic implications, speciation, and chromosomal evolution in Taiwanese Begonia are discussed. Received: January 22, 2002 / Accepted: March 4, 2002  相似文献   

5.
Begonia dregei and B. homonyma (Begoniaceae), rare plants endemic to coastal forests of eastern South Africa, are two closely related species with high levels of variation among populations in the shape of leaves. Distribution of genetic variation and genetic relatedness were investigated in 12 populations of B. dregei and seven of B. homonyma using polyacrylamide gel electrophoresis. Twelve of the 15 enzyme loci examined were polymorphic, but only seven loci were polymorphic within at least one population. Genetic diversity measures indicated that the among-population gene differentiation represents >90% of the total genetic component in both species considered individually or combined. This indicated restricted gene flow, consistent with the limited dispersal abilities of Begonia generally and the ancient separation of isolated forest patches. Genetic distances among populations are much higher than usually found within species. Allozyme data provide no support for the recognition of B. dregei and B. homonyma as distinct species.  相似文献   

6.
More than 200 research papers on the molecular phylogeny and phylogenetic biogeography ofbryophytes have been published since the beginning of this millenium. These papers corroborated assumptions of a complex genetic structure of morphologically circumscribed bryophytes, and raised reservations against many morphologically justified species concepts, especially within the mosses. However, many molecular studies allowed for corrections and modifications of morphological classification schemes. Several studies reported that the phylogenetic structure of disjunctly distributed bryophyte species reflects their geographical ranges rather than morphological disparities. Molecular data led to new appraisals of distribution ranges and allowed for the reconstruction of refugia and migration routes. Intercontinental ranges of bryophytes are often caused by dispersal rather than geographical vicariance. Many distribution patterns of disjunct bryophytes are likely formed by processes such as short distance dispersal, rare long distance dispersal events, extinction, recolonization and diversification.  相似文献   

7.
Aim To devise a robust phylogenetic hypothesis for midwife toads (Alytes: Anura: Discoglossidae) and to discuss its implications for the reconstruction of the biogeographical history of the group. Location Western Palearctic. Methods Analysis of sequences of mitochondrial DNA (cytochrome b and 16S RNA, 861 bp) and 29 characters of cranial osteology of all species and subspecies within Alytes. Results Phylogenetic analyses support a sister group relationship between Alytes dickhilleni and A. muletensis, and of this clade with A. maurus. The monophyly of A. obstetricans is controversial; in particular, the phylogenetic position of A. obstetricans almogavarii is uncertain. The estimated dates for the cladogenetic events within Alytes are congruent with those derived from independent analyses (allozymes), except for the differentiation of A. o. almogavarii and the split between A. dickhilleni and A. muletensis. Main conclusions The phylogeny based on the analysis of morphological and mtDNA data differs from previous hypotheses in the positions of A. o. almogavarii and A. maurus. Events associated with the radiation of Alytes are the formation of large inland saline lakes in Iberia c. 16 Ma and the 11 ° C dramatic decrease in average annual temperature during the Middle–Late Badenian transition c. 14–13.5 Ma (A.cisternasii vs. the ancestor of the remaining clades), the structuring of the Neo‐Pyrenees and the reopening of the Betic Strait c. 10–8 Ma(A. o. almogavarii vs. A. obstetricans and vs. the subgenus Baleaphryne), the opening of the Gibraltar Strait at the end of the Messinian Salinity Crisis at c. 5.3 Ma (A. maurus vs. the ancestor of the A. dickhilleni A. muletensis clade) and a transmarine colonization event at c. 3 Ma (the ancestor of A. muletensis vs. A. dickhilleni). Following the new hypothesis, A. maurus, previously considered a subspecies of A. obstetricans, deserves species status. Second, A. o. almogavarii is a well‐differentiated lineage that was isolated from other A. obstetricans more than c. 5 Ma, but later lost its genetic and specific identity following secondary contact, hybridization and introgression with the main stock. The presence of a marked morphological and genetic diversity within A. obstetricans renders reconstruction of the evolutionary history of the genus more complicated than previously appreciated.  相似文献   

8.
Caltha is a widely distributed genus in the buttercup family (Ranunculaceae) showing interesting distribution patterns in both hemispheres. Evolutionary history ofCaltha was examined by means of phylogenetic, molecular dating, and historical biogeographic analyses with a more comprehensive sampling than previous studies. The internal transcribed spacer from the nuclear genome and trnL-F and atpB-rbcL regions from the plastid genome were used and analyzed using parsimony and Bayesian methods. Divergence time was estimated using Bayesian dating analyses with multiple fossil calibrations. Historical biogeography was inferred using the Bayes-DIVA method implemented in RASP. We obtained a well-resolved and well-supported phylogeny within the Caltha lineage. Caltha natansPall. diverged first from the genus and the other species grouped into two clades. Our expanded sampling scheme revealed a complicated evolutionary pattern in theC. palustris complex. Caltha sinogracilis W. T. Wang was resolved to be a member of the C. palustris complex, rather than closely related to C. scaposa Hook. f. & Thomson. Caltha rubriflora B. L. Burtt & Lauener was also revealed to be not just a red-flower form of C. sinogracilis. The diversification of the genus began at 50.5 mya (95% high posterior density: 37.1–63.9 mya), and its ancestral range was very probably in the Northern Hemisphere. The South American species may derive from western North American ancestors that dispersed along the western American Cordillera during the Cenozoic era. The vicariance model of the Southern Hemisphere species proposed by a previous study was rejected in this study.  相似文献   

9.
Previous studies based on different molecular datasets have generated conflicting topologies for Ranunculeae. Here, we revisit the phylogeny of Ranunculeae by analyzing the individual matK/trnK, psbJ-petA, and internal transcribed spacer (ITS) data, the combined matK/trnK, psbJ-petA, and ITS dataset, and the combinedrbcL, trnL-F, matK/trnK, psbJ-petA, and ITS dataset. Based on the tree-based comparisons, blast searches against NCBI of the sequences, and close examination of the alignment, we found that 10 psbJ-petA sequences previously used were questionable (erroneous or problematic) and responsible for previous conflicting topologies. After omitting these questionable sequences, we provide a new phylogeny for Ranunculeae, in which Beckwithia–Cyrtorhyncha, Kumlienia, andPeltocalathos were replaced. These new replacements are supported by corresponding morphological characters. Moreover, three previously proposed intercontinental disjunct distributions within Ranunculus were also refuted. In our framework, our divergence time and biogeographic analyses indicate that divergence time estimates and the ancestral areas reconstructed for 10 of the 15 nodes in the genus-level phylogeny were influenced by elimination of the questionable sequences. The most recent common ancestor of Ranunculeae was inferred to be present in Europe and North America during the late Eocene. Clades I and II began to diversify in Europe and North America, respectively, and subsequently migrated to other continents. This study shows that it is necessary to analyze individual chloroplast DNA region datasets separately to detect questionable sequences early in the study. The combined dataset including the questionable sequences resulted in an erroneous phylogenetic tree, and the use of this tree subsequently affected age estimates and biogeographic analyses.  相似文献   

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Drosophila is the genus responsible for the birth of experimental genetics, but the taxonomy of drosophilids is difficult because of the overwhelming diversity of the group. In this study, we assembled sequences for 358 species (14 genera, eight subgenera, 57 species groups, and 65 subgroups) to generate a maximum‐likelihood topology and a Bayesian timescale. In addition to sampling an unprecedented diversity of Drosophila lineages, our analyses incorporated a geographical perspective because of the high levels of endemism. In our topology, Drosophila funebris (Fabricius, 1787) (the type species of Drosophila) is tightly clustered with the pinicola subgroup in a North American clade within subgenus Drosophila. The type species of other drosophilid genera fall within the Drosophila radiation, presenting interesting prospects for the phylogenetic taxonomy of the group. Our timescale suggests that a few drosophilid lineages survived the Cretaceous–Palaeogene (K‐Pg) extinction. The drosophilid diversification began during the Palaeocene in Eurasia, but peaked during the Miocene, an epoch of drastic climatic changes. The most recent common ancestor of the clades corresponding to subgenera Sophophora and Drosophila lived approximately 56 Mya. Additionally, Hawaiian drosophilids diverged from an East Asian lineage approximately 26 Mya, which is similar to the age of the oldest emerging atoll in the Hawaiian–Emperor Chain. Interestingly, the time estimates for major geographical splits (New World versus Asia and Africa versus Asia) were highly similar for independent lineages. These results suggest that vicariance played a significant role in the radiation of fruit flies. © 2013 The Linnean Society of London  相似文献   

12.
Aim To determine the origin and diversification of monachine seals using a phylogenetic framework. Methods Molecular sequence data from three mitochondrial genes (cyt b, ND1 and 12S), and one nuclear marker (an intron from the α‐lactalbumin gene) were examined from all extant species of monachine seals. Maximum likelihood and partitioned Bayesian inference were used to analyse separate and combined (mitochondrial + nuclear) data sets. Divergence times were estimated from the resultant phylogeny using nonparametric rate smoothing as implemented by the program r8s. Results Mirounga, Monachus and the Lobodontini form three well‐supported clades within a monophyletic Monachinae. Lobodontini + Mirounga form a clade sister to Monachus. Molecular divergence dates indicate that the first split within the Monachinae (Lobodontini + Mirounga clade and Monachus) occurred between 11.8 and 13.8 Ma and Mirounga, Monachus and the Lobodontini originated 2.7–3.4, 9.1–10.8 and 10.0–11.6 Ma, respectively. Main conclusions Two main clades exist within Monachinae, Monachus and Lobodontini + Mirounga. Monachus, a warm water clade, originated in the North Atlantic and maintained the temperate water affinities of their ancestors as they diversified in the subtropic regions of the Northern Hemisphere. The cold‐water clade, Lobodontini + Mirounga, dispersed southward to the cooler climates of the Southern Hemisphere. The Lobodontini continued south until reaching the Antarctic region where they diversified into the present‐day fauna. Mirounga shows an anti‐tropical distribution either reflective of a once cosmopolitan range that was separated by warming waters in the tropics or of transequatorial dispersal.  相似文献   

13.
Scaptomyza is a highly diversified genus in the family Drosophilidae, having undergone an explosive radiation, along with the Hawaiian‐endemic genus Idiomyia in the Hawaiian Islands: about 60% of 269 Scaptomyza species so far described are endemic to the Hawaiian Islands. Two hypotheses have been proposed for the origin and diversification of Hawaiian drosophilids. One is the “single Hawaiian origin” hypothesis: Scaptomyza and Idiomyia diverged from a single common ancestor that had once colonized the Hawaiian Islands, and then non‐Hawaiian Scaptomyza migrated back to continents. The other is the “multiple origins” hypothesis: Hawaiian Scaptomyza and Idiomyia derived from different ancestors that independently colonized the Hawaiian Islands. A key issue for testing these two hypotheses is to clarify the phylogenetic relationships between Hawaiian and non‐Hawaiian species in Scaptomyza. Toward this goal, we sampled additional non‐Hawaiian Scaptomyza species, particularly in the Old World, and determined the nucleotide sequences of four mitochondrial and seven nuclear genes for these species. Combining these sequence data with published data for 79 species, we reconstructed the phylogeny and estimated ancestral distributions and divergence times. In the resulting phylogenetic trees, non‐Hawaiian Scaptomyza species were interspersed in two Hawaiian clades. From a reconstruction of ancestral biogeography, we inferred that Idiomyia and Scaptomyza diverged outside the Hawaiian Islands and then independently colonized the Hawaiian Islands, twice in Scaptomyza, thus supporting the “multiple origins” hypothesis.  相似文献   

14.
Aim We present a molecular phylogenetic analysis of Brotogeris (Psittacidae) using several distinct and complementary approaches: we test the monophyly of the genus, delineate the basal taxa within it, uncover their phylogenetic relationships, and finally, based on these results, we perform temporal and spatial comparative analyses to help elucidate the historical biogeography of the Neotropical region. Location Neotropical lowlands, including dry and humid forests. Methods Phylogenetic relationships within Brotogeris were investigated using the complete sequences of the mitochondrial genes cyt b and ND2, and partial sequences of the nuclear intron 7 of the gene for Beta Fibrinogen for all eight species and 12 of the 17 taxa recognized within the genus (total of 63 individuals). In order to delinetae the basal taxa within the genus we used both molecular and plumage variation, the latter being based on the examination of 597 skin specimens. Dates of divergence and confidence intervals were estimated using penalized likelihood. Spatial and temporal comparative analyses were performed including several closely related parrot genera. Results Brotogeris was found to be a monophyletic genus, sister to Myiopsitta. The phylogenetic analyses recovered eight well‐supported clades representing the recognized biological species. Although some described subspecies are diagnosably distinct based on morphology, there was generally little intraspecific mtDNA variation. The Amazonian species had different phylogenetic affinities and did not group in a monophyletic clade. Brotogeris diversification took place during the last 6 Myr, the same time‐frame as previously found for Pionus and Pyrilia. Main conclusions The biogeographical history of Brotogeris implies a dynamic history for South American biomes since the Pliocene. It corroborates the idea that the geological evolution of Amazonia has been important in shaping its biodiversity, argues against the idea that the region has been environmentally stable during the Quaternary, and suggests dynamic interactions between wet and dry forest habitats in South America, with representatives of the Amazonian biota having several independent close relationships with taxa endemic to other biomes.  相似文献   

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For sequence analysis of the 12S rRNA gene in spined loaches, specimens of the following taxa were used: Sabanejewia balcanica, Cobitis paludica, C. bilineata, C. fahireae, C. elazigensis, C. elongata , two different sub-populations of C. taenia and four different sub-populations of C. turcica . Phylogenetic relationships among taxa were estimated using parsimony, neighbor-joining, and maximum likelihood algorithms. The calculation of the transition-tranversion ratio indicated that the taxa analysed were rather distantly related. Our analyses using the genus Sabanejewia as an outgroup suggest that C. bilineata is separated from the subgenus Cobitis sensu stricto and placed together with C. elongata as basal to all other species of the genus Cobitis . Support for the placement of C. paludica as basal to both the subgenera Bicanestrinia and Cobitis s. s. (without C. bilineata ) is given by outcomes from three independent methods of phylogenetic reconstruction. A sister-taxon relationship for the subgenera Bicanestrinia and Cobitis s. s. without C. bilineata was consistently found. C. elazigensis was closely related to the population of C. turcica from Lake Beysehir in Turkey. Both formed a sister-group to the remaining populations of C. turcica , while C. fahireae was basal to C. taenia . A molecular clock was calculated based on sequence divergence values and palaeogeographical data. This suggests that different historical colonization routes must have been used by different clades of spined loaches.  相似文献   

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The parrot genus Prioniturus occurs in the oceanic Philippines, Palawan and Wallacea, a geologically dynamic region with a complex history of land and sea. The described taxa of Prioniturus have been variously placed in different assemblages, and different numbers of species have been recognized. However, a phylogenetic framework is so far lacking. This would be the prerequisite to reconstructing dispersal and colonization patterns of Prioniturus across and within Wallacea and the Philippines. Following our robustly supported phylogenetic hypothesis based on two mitochondrial genes, we propose to treat Prioniturus mindorensis comb. nov. as well as Prioniturus montanus and Prioniturus waterstradti as separate species. In Prioniturus discurus discurus and Prioniturus discurus whiteheadi, further studies using additional data and specimens are necessary to clarify their taxonomic status. This result is congruent with other studies demonstrating that alpha diversity of the Philippine avifauna is strongly underestimated. According to our biogeographic reconstruction, Prioniturus has diversified by a complex combination of colonization of islands and subsequent divergence in allopatry among and within island groups. Dispersal between Sulawesi/Wallacea and the Philippines occurred twice and documents a rare case of faunal exchange between these two regions.  相似文献   

19.
Qiao CY  Ran JH  Li Y  Wang XQ 《Annals of botany》2007,100(3):573-580
BACKGROUND AND AIMS: Cedrus (true cedars) is a very important horticultural plant group. It has a disjunct distribution in the Mediterranean region and western Himalaya. Its evolution and biogeography are of great interest to botanists. This study aims to investigate the phylogeny and biogeography of Cedrus based on sequence analyses of seven cytoplasmic DNA fragments. METHODS: The methods used were PCR amplification and sequencing of seven paternal cpDNA and maternal mtDNA fragments, parsimony and maximum likelihood analyses of the DNA dataset, and molecular clock estimate of divergence times of Cedrus species. KEY RESULTS: Phylogenies of Cedrus constructed from cpDNA, mtDNA and the combined cp- and mt-DNA dataset are identical in topology. It was found that the Himalayan cedar C. deodara diverged first, and then the North African species C. atlantica separated from the common ancestor of C. libani and C. brevifolia, two species from the eastern Mediterranean area. Molecular clock estimates suggest that the divergence between C. atlantica and the eastern Mediterranean clade at 23.49 +/- 3.55 to 18.81 +/- 1.25 Myr and the split between C. libani and C. brevifolia at 7.83 +/- 2.79 to 6.56 +/- 1.20 Myr. CONCLUSIONS: The results, combined with palaeogeographical and palaeoecological information, indicate that Cedrus could have an origin in the high latitude area of Eurasia, and its present distribution might result from vicariance of southerly migrated populations during climatic oscillations in the Tertiary and further fragmentation and dispersal of these populations. It is very likely that Cedrus migrated into North Africa in the very late Tertiary, while its arrival in the Himalayas would not have been before the Miocene, after which the phased or fast uplift of the Tibetan plateau happened.  相似文献   

20.
We infer for the first time the phylogenetic relationships of genera and tribes in the ecologically and evolutionarily well‐studied subfamily Nymphalinae using DNA sequence data from three genes: 1450 bp of cytochrome oxidase subunit I (COI) (in the mitochondrial genome), 1077 bp of elongation factor 1‐alpha (EF1‐α) and 400–403 bp of wingless (both in the nuclear genome). We explore the influence of each gene region on the support given to each node of the most parsimonious tree derived from a combined analysis of all three genes using Partitioned Bremer Support. We also explore the influence of assuming equal weights for all characters in the combined analysis by investigating the stability of clades to different transition/transversion weighting schemes. We find many strongly supported and stable clades in the Nymphalinae. We are also able to identify ‘rogue’ taxa whose positions are weakly supported (the different gene regions are in conflict with each other) and unstable. Our main conclusions are: (1) the tribe Coeini as currently constituted is untenable, and Smyrna, Colobura and Tigridia are part of Nymphalini; (2) ‘Kallimini’ is paraphyletic with regard to Melitaeini and should be split into three tribes: Kallimini s.s., Junoniini and Victorinini; (3) Junoniini, Victorinini, Melitaeini and the newly circumscribed Nymphalini are strongly supported monophyletic groups, and (4) Precis and Junonia are not synonymous or even sister groups. The species Junonia coenia, a model system in developmental biology, clearly belongs in the genus Junonia. A dispersal‐vicariance analysis suggests that dispersal has had a major effect on the distributions of extant species, and three biotic regions are identified as being centres of diversification of three major clades: the Palaearctic for the Nymphalis‐group, the Afrotropics for Junoniini and the Nearctic for Melitaeini. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 86 , 227–251.  相似文献   

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