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1.
This study deals with the phenology, pollination biology and floral morphology of Myrsine laetevirens , a neotropical dioecious tree. In Punta Lara (Argentina), its flowering period occurs during January-February. Both pistillate and staminate flowers are small, with a yellowish-green perianth and produce neither nectar nor odour. Staminate flowers have five stamens and a vestigial gynoecium while pistillate flowers, have non-functional anthers and a conspicuous stigma. The floral characteristics of staminate and pistillate plants are related to the syndrome of anemophily. Fruit set in inflorescences covered with mesh bags and observations prove that animals are not involved in the pollination process. A provisional cladistic analysis of Myrsinaceae shows that dioecy evolved as one of the most recent apomorphies of Myrsine and is part of the anemophilous syndrome.  相似文献   

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The genus Parardisia is shown to be synonymous with the large pantropical genus Ardisia . The species on which Parardisia was based, A. involucrata , should therefore retain that original name. The only other species assigned to Parardisia, P. gamblei , is reduced to synonymy with Ardisia moultonii; both were described (and still known only) from Sarawak. The first species retains its position in Ardisia subgenus Tinus , while the latter belongs in subgenus Tinopsis .  相似文献   

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Ardisia dawnaea is for the first time reported from Thailand; a new combination: Ardisia sanguinolenta var. paralleloneura is made; two names: Ardisia dawnensis and Ardisia undulatodentata are reduced to synonymy, and some confused or misidentified species of Ardisia are clarified.  相似文献   

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The comparative floral ontogeny of five species belonging to the primuloid clade of the Ericales are investigated, viz. Maesa japonica, M. perlarius, Aegiceras corniculatum, Embelia laeta and E. ribes. All five species basically show 2/5-spiral phyllotaxis of the sepal primordia, although with some minor modification (particularly in Embelia, where the flowers are predominantly tetramerous). The phyllotaxis of the common petal-stamen primordia is also 2/5-spiral in the Maesa and Aegiceras species investigated, but appears to be unidirectional in Embelia. All five species develop common petal-stamen primordia in which the resultant petal primordia are larger than the stamen primordia, and in which the stamens develop proximally on the adaxial flank of the common primordia. Growth of the placenta in Maesa and Aegiceras partially embeds the ovules, but in Embelia the ovules are almost fully immersed in placental tissue at maturity. A comprehensive review of all previously published studies of floral ontogeny of primuloid genera is presented, and the phylogenetic significance of the variation between genera is evaluated with reference to recently published cladograms.  相似文献   

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Five species (A. escallonioides Schltdl. & Cham., A. hirtella Lundell, A. elliptica Thunb., A. sieboldii Miq., and A. wallichii A.DC.) from three subgenera in the genus Ardisia (Myrsinaceae) were examined for self-compatibility, agamospermy, and autogamy using hand-pollination and pollinator-exclusion experiments on both garden plants and wild populations. All five species are self-compatible but not agamospermous. Four of the five species exhibited autogramy. Autogamy was strongly associated with stamen position, anther dehiscence type, protogyny, and inflorescence type. Because self-compatibility is widespread across different subgenera, it may be a general characteristic of the genus Ardisia. The potential impact of self-compatibility on the mating system and population genetic structure is discussed.  相似文献   

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Symbiotic leaf-nodule bacteria in nodulated members of Rubiaceae live in mucilage secreted by colleters located on stipules within buds. These differ from colleters on most nodule-free species. This study was undertaken to examine buds of Ardisia and the related monotypic Amblyanthus of Myrsinaceae to see if nodulated species had secretory structures dissimilar from those of nodule-free species. Buds removed from herbarium specimens (61 species) and live plants (3 species) were paraffin-sectioned. Diverse trichome forms occur, including dimorphism between adaxial and abaxial trichomes in some species. Species within each subgenus were arranged according to trichome form: peltate scale, irregularly capitate, capitate, sessile capitate, bicellular capitate, and uniseriate. Only seven Ardisia species (all in subgenus Crispardisia, widely assumed to have bacteria in marginal leaf nodules of all 30 species) have short-lived trichomes bearing one or more elongate, swollen, distal cells that appear to be secretory cells. These trichomes are analogous to the dendroid or brushlike colleters of nodulated Rubiaceae. Druses occur in most subgenera and this appears to be by far the most predominant crystal type m Ardisia.  相似文献   

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Two new taxa of Ardisia from Thailand, A. integra and A. corymbifera var. euryoides , are described and illustrated.  相似文献   

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红毛毡的染色体数目及核型报道   总被引:3,自引:0,他引:3  
红毛毡(Ardisia mamillata Hance)属于紫金牛科(Myrsinaceae)紫金牛属(Ardisia),主产于我国云南、四川、贵州、广西、广东等省。生长于密林下阴湿的地方。红毛毡是一种常用的中草药,全草有清热利湿、活血止血、去腐生肌之功效(云南植物研究所,1977);同时,花粉红色,每花序有花7~15朵,果实球形,宿存,鲜红色,也是一种很好的花果兼具的观赏植物。  相似文献   

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Summary The ultrastructure and amino acid composition of the secreted silk of two species of trichopteran larvae, Pycnopsyche guttifer (Walk.) and Neophylax concinnus McL., were investigated. The spinnerets of these two animals were also examined by scanning electron microscopy. The silk consists of double-stranded, flat ribbons (1–4 wide), composed of bundles of 15–25 Å filaments. There are two components of the silk: the fiber proper and a surrounding coat thought to be a silk gum. Only the outer coat is positive to the EM PATP technique of Thiery (1967), which indicated the presence of neutral sugars. Amino acid analyses of Pycnopsyche silk show that, like other silks, two predominant amino acids are glycine and serine. Arginine, unexpectedly, is the third most abundant and there are a large number of basic and long side-chain amino acids. X-ray diffraction studies of the silk indicate that it has a less crystalline, more amorphous structure than that of other silks.Submitted to the Department of Biological Sciences of the State University of New York at Albany in partial fulfillment of the requirements for the degree of Doctor of Philosophy Acknowledgements. This study was supported in part by a National Institutes of Health Graduate Student Traineeship grant # GM-02014. The author would like to express sincere gratitude to Dr. Stephen Brown for his encouragement and help during the course of this study. I would also like to thank Dr. Curtis Hemenway and Mr. Douglas Halgren of Dudley Observatory for the use of their scanning electron microscope as well as Dr. Helen Ghiradella and Mr. William Radigan for help with the scanning electron microscopy. I owe special appreciation to Dr. Y. Myer of the Chemistry Department of SUNYA for doing an amino acid analysis of the silk and to Dr. K.M. Rudall of the University of Leeds for doing the X-ray diffraction studies of the silk samples  相似文献   

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A morphological and anatomical investigation is presented of the two species of Heberdenia, H. bahamensis (Macaronesia) and H. penduliflora (Mexico). A cladistic analysis including 27 taxa of the Myrsinaceae and using Jacquinia (Theophrastaceae) and Manilkara (Sapotaceae) as outgroup was performed to provide a hypothesis of the relationships of the two species of Heberdenia. It was concluded that H. bahamensis and H. penduliflora are not more closely related to each other than either is to many other species of the Myrsinaceae, and that they should not be referred to the same genus. Heberdenia bahamensis appears to be most closely related to the Old World genera Pleiomeris, Embelia , and Grenacheria , whereas H. penduliflora is nested within Ardisia s. L , possibly being most closely related to the segregate genus Gentlea. It is suggested that H. penduliflora is probably best referred to a genus of its own.  相似文献   

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The influence of the oral administration of Juzen-Taiho-To (JTT; Si-Quan-Da-Bu-Tang in Chinese), a Kampo (Japanese herbal) medicine, on the cytokine production in mice were investigated. Lymphocytes from spleen (SPN), mesenteric lymph node (MLN) and Peyer's patches (PP) from mice, which received orally administered JTT for 2 weeks, were stimulated with concanavalin A (Con A), and the resulting conditioned medium was tested for cytokine production by ELISA. Administration of JTT caused enhancement of interferon g (IFN-gamma) and interleukin-4 (IL-4) production to some extent but decreased IL-5 production from the SPN. On the other hand, notable changes in cytokine production were observed in lymphocytes from MLN and PP. Administration of JTT increased IFN-gamma production remarkably, as well as IL-5 secretion from both MLN and PP, whereas IL-2 secretion was plainly reduced. The ratio of IFN-gamma and IL-4 was shifted to Th1 dominant in MLN and PP, however changed little in SPN. The flow cytometric analysis revealed that the population of CD3+, CD4+, CD45R/B220+, and CD45RBlowCD4+ cells in each lymphocyte was not changed significantly after oral administration of JTT. These findings demonstrate that the lymphocytes from gut associated lymphoreticular tissues (GALT) are more sensitive to produce cytokines on cytokine production than those from SPN by oral administration of JTT, and that the modulation of cytokine production may be due to functional change of lymphocytes but not change in lymphocytes population.  相似文献   

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报道了发现于浙江苍南县的紫金牛属一新变型--黄果朱砂根(Ardisia crenata Sims f.xanthocarpa F.Y.Zhang et G.Y.Li),该新变型果实为黄色,而原变型为鲜红色.  相似文献   

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It has been suggested that rbcL and matK are the core barcodes in plants, but they are not powerful enough to distinguish between closely related plant groups. Additional barcodes need to be evaluated to improve the level of discrimination between plant species. Because of their well-studied taxonomy and extreme diversity, we used Chinese Lysimachia (Myrsinaceae) species to test the performance of core barcodes (rbcL and matK) and two additional candidate barcodes (trnH-psbA and the nuclear ribosomal ITS); 97 accessions from four subgenus representing 34 putative Lysimachia species were included in this study. And many closely related species pairs in subgen. Lysimachia were covered to detect their discriminatory power. The inefficiency of rbcL and matK alone or combined in closely related plant groups was validated in this study. TrnH-psbA combined with rbcL + matK did not yet perform well in Lysimachia groups. In contrast, ITS, alone or combined with rbcL and/or matK, revealed high resolving ability in Lysimachia. We support ITS as a supplementary barcode on the basis of core barcode rbcL and matK. Besides, this study also illustrates several mistakes or underlying evolutionary events in Lysimachia detected by DNA barcoding.  相似文献   

20.
Aegiceras corniculatum is an ecologically important mangrove tree species. We isolated 18 polymorphic microsatellite loci from this species. These loci provided microsatellite markers with polymorphism of two to eight alleles per locus. The observed and expected heterozygosities ranged from 0.050 to 0.550, and from 0.097 to 0.736, respectively. These markers will contribute to research on the conservation, genetic diversity and mating patterns of A. corniculatum.  相似文献   

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