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1.
Abstract

The first unambiguous documentation of hybridism in the genus Doronicum (Senecioneae – Asteraceae) is reported. All our morphological, karyological and molecular data concur to indicate that Doronicum × minutilloi Peruzzi hybr. nov. (2n = 60) is a hybrid growing in Monti Aurunci (Central Italy), originated from the spontaneous crossing D. orientale Hoffm. (2n = 60) × D. columnae Ten. (2n = 60). This new hybrid shows a slightly higher morphological, karyotypic and ribotypic affinity with D. columnae, but shares a trnL-trnF IGS haplotype with D. orientale, and co-occurs with the latter species only; it has reduced fertility and a high potential for vegetative propagation through rhizome fragmentation. Our results led us to suspect in fieri homoploid hybrid speciation.  相似文献   

2.
Doronicum caucasicum M. Bieb. (Compositae: Senecioneae) is described and illustrated for the second time in the history of Curtis's Botanical Magazine. Critical examination and reading of the works in which the protologues were published has led to the conclusion that D. caucasicum was published earlier than D. orientale Hoffm., but it is highly likely that the two names were based on the same Adams collection that Adams had annotated as Doronicum orientale. The possibility of Doronicum L. being the sole genus in the recently proposed tribe Doroniceae Panero is discussed. The lack of any present infrageneric classification is commented upon, but this is probably due to insufficient characters in the multivariate analyses used, and where the limits are drawn in molecular analyses. Cultivation and propagation guidelines for the species are provided and currently availability of cultivars is outlined, as are likely pests and diseases.  相似文献   

3.
Isoetin, 5,7,2′,4′,5′-pentahydroxyflavone, is a rare, structurally simple natural product belonging to the flavone sub-group of flavonoids. The first reports on naturally occurring isoetin derivatives were published in the 1970s though methoxy-derivatives with the same substitution pattern had already been synthesized a decade earlier. A glucoside of isoetin was first discovered in the genus Isoetes (Lycopodiopsida). In the forty years following the discovery of the new naturally occurring flavonoid aglycone, only a limited number of reports on isoetin and its derivatives have been published. Simple, i.e. non-methyl-ether derivatives of isoetin have been found in the Isoetaceae, Asteraceae, Ranunculaceae, Rosaceae, and Rubiaceae families; while methyl ethers and their derivatives have been found in the Lycopodiaceae, Asteraceae, Cucurbitaceae, Fabaceae, and Pedaliaceae. A total of 14 non-methyl-ether-derivatives (including isoetin) and the same number of methyl ether derivatives have been described, some methyl derivatives only as synthetic compounds, others even only as virtual compounds generated for in silico studies. The published NMR data of isoetin and its derivatives as well as chemosystematic studies using isoetin derivatives as markers are compiled and critically assessed. Moreover, the papers dealing with bioactivities of isoetin and its derivatives are summarized.  相似文献   

4.
The phylogenetic position of diatoms belonging to the genus Attheya is presently under debate. Species belonging to this genus have been placed in the subclasses Chaetocerotophycidae and Biddulphiophycidae, but published phylogenetic trees based on 18S rDNA, morphology, and sexual reproduction indicate that this group of diatoms may be a sister group of the pennates. To clarify the position of Attheya, we studied the morphology, 18S rDNA, 16S rDNA of the chloroplasts, the rbcL large subunit (LSU) sequences of the chloroplasts, and the sterol composition of three different strains of Attheya septentrionalis (Østrup) R. M. Crawford and one strain of Attheya longicornis R. M. Crawford et C. Gardner. These data were compared with data from more than 100 other diatom species, covering the whole phylogenetic tree, with special emphasis on species belonging to the genera that have been suggested to be related to the genus Attheya. All data suggest that the investigated Attheya species form a separate group of diatoms, and there is no indication that they belong to either the Chaetocerotophycidae or the Biddulphiophycidae. Despite applying these various approaches, we were unable to determine the exact phylogenetic position of the investigated Attheya species within the diatoms.  相似文献   

5.
6.
据观察,沫蝉科Sphenorhina属的3个种都以菊科的Crassocephalum cerpidioidesChromolaena ordorata 作为寄主植物,热带菊科植物与固氮植物有关,沫蝉可以作为菊科一些固氮植物的间接指示物,目前尚未得到很好研究。  相似文献   

7.
8.
A broad survey of the Asteraceae, involving visual characters, was undertaken to ascertain the occurrence of possible Kranz-type (C4) plants. One hundred and seven taxa representing 51 genera were examined by mass spectrometry for their 13C/12C ratios in dried leaf tissue. Species possessing the high 13C/12C ratio typical of the Kranz syndrome were found in genera belonging to the following tribes: Heliantheae (subtribe Coreopsideae)—Chrysanthellum (4 spp.), Eryngiophyllum (1 sp.), Glossocardia (1 sp.), Glossogyne (1 sp.), Isostigma (5 spp.); Tageteae—Pectis (21 spp.); and Helenieae—Flaveria (4 spp.). The only genus to possess both C3 and C4 species was Flaveria in which all but four species appear to possess a C3-type metabolism. When appropriate, the phyletic input of these data is discussed.  相似文献   

9.
Stenomitos terricola FBCC-A190 was collected from soils around the trees of Mt. Gwanggyo, located in Yeongtong-gu, Suwon-si, Gyeonggi-do. S. terricola FBCC-A190 is a thin and simple filament with a cell length that is longer than its width. It has a thin and firm sheath, exhibiting a blue-green color. Species belonging to genus Stenomitos is semi-cryptic species with slight morphological differences from each other. They were confirmed as Stenomitos species by analysis using 16S rRNA and 16S–23S ITS. A monophyletic cluster was formed with the previously reported genus Stenomitos, with 16S rRNA gene sequences sharing similarities of 95.9–97.9% except for S. pantisii TAU-MAC 4318. In addition, 16S–23S ITS gene sequencing showed tRNAAla, tRNAIle and V2, similar to the previously reported genus Stenomitos. From these results, Stenomitos terricola sp. nov. was proposed as a new species belonging to genus Stenomitos.  相似文献   

10.
There are relatively few studies of DNA content in the Vernonieae (Asteraceae) tribe. The first studies were realized in the Lessingianthus genus and determined the DNA content of 25 species. After DNA content, ploidy level and the total karyotype were compared in 6 Chrysolaena species. The aim of this study was to present, for the first time, the DNA content values of Vernonanthura and Vernonia and to thereby expand knowledge of the Vernonieae tribe. A total of 19 natural populations belonging to the genera Vernonanthura and Vernonia were studied for the first time. The results were compared with other Vernonieae genera and with other Asteraceae tribes. Our results found that Vernonieae have the smallest range of 1C value variation in Asteraceae. Furthermore, there were differences in the DNA content of Vernonia and Vernonanthura. These results show that low DNA content and herbaceous habit in Vernonia are characters derived from the higher DNA content and woody habit present in Vernonanthura. These results could indicate a hybrid origin of one species and allow the determination of both the ploidy and chromosome number of other taxa. The results observed in Vernonanthura species showed a highly significant correlation between 1C-value and latitude.  相似文献   

11.
Cissampelos is a significant genus comprising of approximately 21 species of the medicinal plants (Menispermaceae). The plants of this genus are used in traditional medicine for the treatment of various ailments such as asthma, arthritis, dysentery, hyperglycemia, cardiopathy, hypertension and other related problems. These plants are rich in bioactive dibenzylisoquinoline and aborphine as well as small amounts of other ingredients. In recent years, the chemical constituents and pharmacological activities of Cissampelos genus have been paid more and more attention due to their diversity. Herein, we compile the chemical constituents and biological activities on this genus, and summarize the 13C-NMR data of the main bioactive ingredients. All information comes from scientific databases such as Google Scholar, PubMed, Sci-Finder, ScienceDirect, Web of Science and CNKI. It provides valuable data for the future research and development of Cissampelos genus.  相似文献   

12.
The Asteraceae family comprises ca. 1000 genera, mainly distributed in Asia and Europe. Saussurea DC., as the largest subgenus of this family, comprises ca. 400 species worldwide, of which ca. 300 species occur in China. Most plants in China grow wild in the alpine zone of the Qingzang Plateau and adjacent regions at elevations of 4000 m. Plants of the genus Saussurea (Asteraceae) are used in both traditional Chinese folk medicine and Tibet folklore medicine, since they are efficacious in relieving internal heat or fever, harmonizing menstruation, invigorating blood circulation, stopping bleeding, alleviating pain, increasing energy, and curing rheumatic arthritis. A large number of biologically active compounds have been isolated from this genus. This review shows the chemotaxonomy of these compounds (215 compounds) such as sesquiterpenoids (101 compounds), flavonoids (19 compounds), phytosterols (15 compounds), triterpenoids (25 compounds), lignans (32 compounds), phenolics (23 compounds), and chlorophylls (11 compounds). Biological activities (anti‐inflammatory, anticancer, antitumor, hepatoprotective, anti‐ulcer, cholagogic, immunosuppressive, spasmolytic, antimicrobial, antiparasitic, antifeedant, CNS depressant, antioxidant, etc.) of these compounds, including structure–activity relationships, are also discussed.  相似文献   

13.
Heterocoma is a Brazilian endemic genus resulting from the dismemberment of Sipolisiinae, in which only representatives with fruit containing phytomelanin were included in the genus. As the fruits of Asteraceae are known to be systematically important at various taxonomic levels and Heterocoma fruit has not been described previously, we studied the morphology and anatomy of the cypselas of all species of the genus, comparing them with other fruits in the family containing phytomelanin and evaluating the systematic potential at the specific and tribal levels. The fruits were analysed by scanning electron microscopy (SEM) and light microscopy. The morphological features of the fruit, including the carpopodium, ribs and pappi, varied in the genus and demonstrated potential for species discrimination. The anatomy showed a pattern for the genus with a uniseriate exocarp, the outer mesocarp composed of fibres arranged in several layers, the inner mesocarp composed of several layers of parenchyma, the endocarp, and phytomelanin deposited between the inner and outer mesocarp. This anatomical pattern of phytomelanin deposition differs from that of other Asteraceae with phytomelanin in their fruit. Heterocoma is also the only genus in Vernonieae that has phytomelanin deposition in the cypselas. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 255–265.  相似文献   

14.
Data on the spermatozoa of Branchiobdellida were taken from the published literature: sperm models of 25 species belonging to 13 different branchiobdellidan genera have been compared with the aim of supplying further evidences for a phylogenetic analysis of the group. The species considered were representative of all traditional branchiobdellidan families, excluding the monotypic Caridinophilidae. Branchiobdellidan spermatozoa are complex cells, thus it was possible to analyse the variation of 20 characters within the group. A parsimony analysis has yielded nine minimal trees, eight of which are very similar to one another. The main conclusions of the phylogenetic analysis are: (a) the monophyly of the taxon Branchiobdellida is confirmed; (b) the most speciose branchiobdellidan genus, Cambarincola is polyphyletic; (c) none of the traditional ‘families’ are supported; (d) the genus Branchiobdella is monophyletic, but the position of one species, B. kobayashi, albeit basal to the whole genus, is not resolved; (e) the other two genera analysed for which more than one species was available, Pterodrilus and Xironogiton, are monophyletic; (f) there seems to be a ‘trend’ in the whole group towards an increase of acrosome length. Our results partly parallel those obtained by Gelder and Siddall (2000) with a combined analysis of molecular and somatic characters, and point to the need for a comprehensive revision of the Branchiobdellida based on a combination of molecular, somatic and spermatological data sets.  相似文献   

15.
An authentic soluble metallo-protein nucleotide pyrophosphatase/phosphodiesterase (ELNPP) was purified to homogeneity from Euphorbia characias latex. The native protein had a molecular mass of 80 ± 5 kDa and was shown to be formed by two apparently identical subunits, each containing 1 Ca2+ and 1 Mg2+ ion. Whereas Mg2+ was shown to be strongly bound to the enzyme, Ca2+ was easily removed by treatment with EDTA. Ca2+-demetalated enzyme was shown to be almost totally inactive and the activity was fully restored incubating the demetalated ELNPP with Ca2+ ions. ELNPP exhibited hydrolytic activities toward pyrophosphate/phosphodiester bonds of a broad range of substrates and very efficiently hydrolyzed the artificial substrate thymidine 5′-monophosphate 4-nitrophenyl ester generating 4-nitrophenolate as a final product, and it has been used for enzyme kinetic experiments. ELNPP represents the first example of a nucleotide pyrophosphatase/phosphodiesterase enzyme purified from the latex of a plant belonging to the large genus Euphorbia.  相似文献   

16.
Baccharis is a widespread genus belonging to the Asteraceae family that includes almost 400 species exclusively from the Americas. Even when studied in detail, the taxonomic classification among species from this genus is not yet fully defined. Within the framework of our study of the volatile composition of the Baccharis genus, four species (B. trimera, B. milleflora, B. tridentata, and B. uncinella) were collected from the ‘Campos de Cima da Serra’ highlands of the Brazilian state of Rio Grande do Sul. The aerial parts were dried and extracted by the simultaneous distillation extraction (SDE) procedure. This is the first time that SDE has been applied to obtain and compare the volatile‐extract composition in the Baccharis genus. Characterization of the volatile extracts allowed the identification of 180 peaks with many coeluting components; these latter being detailed for the first time for this genus. The multivariate statistical analyses allowed separating the volatile extracts of the four populations of Baccharis into two separate groups. The first one included the B. milleflora, B. trimera, and B. uncinella volatile extracts. The three species showed a high degree of similarity in their volatile composition, which was characterized by the presence of high contents of sesquiterpene compounds, in particular of spathulenol. The second group comprised the extract of B. tridentata, which contained α‐pinene, β‐pinene, limonene, and (E)‐β‐ocimene in high amounts.  相似文献   

17.
A cladistic analysis of the genusAnisopappus (Asteraceae: Inuleae) has been undertaken. A hypothesis of species interrelationships in the genus is presented for the first time. The analysis also includedArctotis (Arctoteae), used as outgroup, and five additional genera from theInuleae: Geigeria, Calostephane, Asteriscus, Buphthalmum, Pulicaria, andInula. It is concluded thatAnisopappus is a monophyletic group situated at the base of the tribe, diagnosed by, e.g., their obtuse stylar sweeping-hairs. The species with acute sweeping-hairs were found to be derived within the genus. Problems concerning species delimitation, biogeography and character evolution in the genus are briefly discussed.  相似文献   

18.
A geometric morphometric analysis was carried out on the crania of 13 species of elephant-shrews (Macroscelidea), a group of African mammals whose phylogeny is still debated. The material examined consisted of 313 crania and included all the genera of Macroscelididae, the unique family recognized by taxonomists. The results obtained from the analysis of the cranium shape and size, either from dorsal or lateral view, were very similar. The first one appeared more reliable because of the higher number of intersection points fixed between the cranial sutures. All the cranial features that distinguished the genus Rhynchocyon were a consequence of the extreme enlargement of frontal bones. Instead, within the subfamily Macroscelidinae, the differences between genera were based on modification involving other bones, mainly mastoids and nasals, as shown by the deformation grids. A cluster analysis confirmed the traditional subdivision in two subfamilies (Rhynchocyoninae and Macroscelidinae) but suggested a different relationship among the recognized genera belonging to Macroscelidinae. Our results are congruent with data obtained from previous biochemical research and support the traditional subdivision in two subfamilies, the monophily of the genus Elephantulus and its closeness with Petrodromus, relating to their similar cranium shapes. The latter presumably is a case of gigantism as adaptation to forest habitats. Further studies on all the species of Elephantulus could provide new evidence for assessing the relationships within this clade, including Macroscelides that by the present analysis appeared as a well-distinguished taxonomic entity.  相似文献   

19.
A chemosystematic study of eleven species from the genus Lactuca (Asteraceae) was performed, based on the distributional data for eight sesquiterpene lactones as diagnostic characters. The lactones were identified in leaf and root extracts by comparison of their HPLC retention times and on-line UV spectra with those of reference compounds. Our results support the status of the section Lactuca, subsection Lactuca as a recognizable group within the genus, although Lactuca aculeata is a distinct species. Moreover, sesquiterpene lactone patterns of Lactuca perennis, Lactuca tatarica, Lactuca indica and Lactuca capensis are also given. It is worth noting that the sesquiterpene lactones are absent from Lactuca tenerrima. The chemosystematic impact of lactucin-type guaianolides and the germacranolide lactuside A is discussed briefly.  相似文献   

20.
This article describes a new diatom genus Moreneis from the Yellow Sea sand flats on the west coast of Korea. The new genus is characterized by a unique combination of morphological characteristics, including the shape of the plastids, which have not been previously observed in diatoms. The valve morphology resembles other genera belonging to Lyrellaceae, within which we place this genus. In terms of areolae structure, Moreneis resembles Petroneis and Placoneis; however, it differs from both genera with respect to the raphe system and plastid shape. Cells of Moreneis spp. have a single large plastid appressed to the girdle of the secondary side of the valve, with two lobes extended toward the primary side of the valve. Furthermore, the unique feature of Moreneis frustules is the raphe, which has both external central and apical endings bent in opposite directions. We differentiated four taxa, which we describe as new for science. However, based on our findings, several established species from Navicula should also be formally transferred to Moreneis, including N. alpha Cleve, N. besarensis Giffen, N. epsilon Cleve, N. menaiana Hendey, N. polae Heiden, and N. quadri‐undulata F. Meister. Analysis of published data revealed that species belonging to Moreneis are numerous in tropical marine littoral waters, and in moderate climate zones, especially in the western Pacific, with only a few species occurring in the Mediterranean and Atlantic.  相似文献   

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