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1.
Cremanthodium latilobum Y. S. Chen and C. medogense Y. S. Chen, two new species from Chinese eastern Himalaya are described and illustrated. A diagnostic key to the species of Cremanthodium section Pinnatinervia Y. Ling & S. W. Liu series Cuneata Y. Ling & S. W. Liu is provided.  相似文献   

2.
通过标本检查,发现小五台银莲花(Anemone xiaowutaishanica W.T.WangBing Liu)与银莲花(A.cathayensis Kitag.ex ZimanKadota)属于同一种植物,故将前者处理为后者的异名。由于银莲花属于银莲花亚组[subsection Omalocarpus(DC.)Tamura],故同时将根据小五台银莲花而建立的小五台银莲花组(section Leptothece W.T.WangBing Liu)处理为银莲花亚组的异名。  相似文献   

3.
Based on examinations of specimens of Elatostema and Pellionia housed at K, KUN, L, P, PE, and YUNU, Elatostema section Weddelia series Salvinioida is taxonomically revised. Two species are recognized, described, and illustrated, and a key to the species is provided. Elatostema salvinioides var. robustum W.T.Wang is treated as a synonym of E. salvinioides W.T.Wang. Pellionia imbricata Gagnepain is transferred to Elatostema and a lectotype is designated herein. A new name, Elatostema simplicissimum Q. Lin, is provided because Elatostema imbricans was previously occupied. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 62–66.  相似文献   

4.
We have identified multiple alleles for a single gene termed W14/15. This gene encodes closely related but not identical proteins W14 and W15 that accumulate in overwinter buds of Gentiana triflora (Takahashi et al. in Breed Sci 56:39–46, 2006; Hikage et al. in Mol Genet Genomics 278:95–104, 2007). In this study, structural analysis of the W14/15 gene was carried out for 21 different gentian lines/cultivars consisting of 5 different species, to survey species- or line/cultivar-specific haplotypes. Within the samples examined, multiple variant forms were found. Those were categorized into seven major types (type I–VII) and ten subtypes based on the presence of three short insertion/deletion sites, three RFLP sites, and several SNP sites. Each line/cultivar had a distinct set of W14/15 gene variants for an allelic pair. Phylogenetic analysis showed that the W14/15 alleles cluster into groups that are characteristic of gentian species, i.e., G. triflora, G. scabra, G. pneumonanthe, G. septemfida and an unknown species other than the former four. In addition, within the same gentian species, different sets of haplotypes were found. Thus, the W14/15 alleles provide useful landmarks to resolve phylogenies of the genus or section Gentiana, as well as to analyze pedigree and breeding history of the cultivars derived from those Gentiana sp.  相似文献   

5.
The establishment of epitypes (together with the emended diagnoses) for three species of Euglenaria Karnkowska, E. W. Linton et Kwiatowski [Eu. anabaena (Mainx) Karnkowska et E. W. Linton; Eu. caudata (Hübner) Karnkowska et E. W. Linton; and Eu. clavata (Skuja) Karnkowska et E. W. Linton] and two species of Euglena Ehrenberg [E. granulata (Klebs) Schmitz and E. velata Klebs] was achieved due to literature studies, verification of morphological diagnostic features (cell size, cell shape, number of chloroplasts, the presence of mucocysts), as well as molecular characters (SSU rDNA). Now all these species are easy to identify and distinguish, despite their high morphological similarity, that is, spindle‐shaped (or cylindrically spindle‐shaped) cells and parietal, lobed chloroplasts with a single pyrenoid, accompanied by bilateral paramylon caps located on both sides of the chloroplast. E. granulata is the only species in this group that has spherical mucocysts. E. velata is distinguished by the largest cells (90–150 μm) and has the highest number of chloroplasts (>30). Eu. anabaena has the fewest chloroplasts (usually 3–6), and its cells are always (whether the organism is swimming or not) spindle‐shaped or cylindrically spindle‐shaped, in contrast to the cells of Eu. clavata, which are club‐shaped (clavate) while swimming and only after stopping change to resemble the shape of a spindle or a cylindrical spindle; Eu. clavata has numerous chloroplasts (15–20). Eu. caudata is characterized by asymmetrical spindle‐shaped (fusiform) cells, that is, with an elongated rear section and a shorter front section; the number of chloroplasts normally ranges from 7 to 15.  相似文献   

6.
Smith (1944) divided the familiar genus Volvox L. into four sections, placing seven species that lacked cytoplasmic bridges between adult cells in the section Merrillosphaera. Herein, we describe a new member of the section Merrillosphaera originating from Texas (USA): Volvox ovalis Pocock ex Nozaki et A. W. Coleman sp. nov. Asexual spheroids of V. ovalis are ovoid or elliptical, with a monolayer of 1,000–2,000 somatic cells that are not linked by cytoplasmic bridges, an expanded anterior region, and 8–12 gonidia in the posterior region. Visibly asymmetric cleavage divisions do not occur in V. ovalis embryos as they do Volvox carteri F. Stein, Volvox obversus (W. Shaw) Printz, and Volvox africanus G. S. West, so the gonidia of the next generation are not yet recognizable in V. ovalis embryos prior to inversion. Molecular phylogenetic analyses of the five chloroplast genes and the internal transcribed spacer (ITS) regions of nuclear rDNA indicated that V. ovalis is closely related to Volvox spermatosphaera Powers ( Powers 1908 , as “spermatosphara”) and/or Volvox tertius Art. Mey.; however, V. ovalis can be distinguished from V. spermatosphaera by its larger gonidia, and from V. tertius by visible differences in gonidial chloroplast morphology.  相似文献   

7.
Liparis tsii, a new orchid from Guangdong, China, is described and illustrated. It is compared with its closest allies: L. sasakii Hayata, L. nanlingensis H.Z. Tian & F.W. Xing, L. krameri Franch. & Sav., L. reckoniana T.C. Hsu and L. brunnea Ormerod belonging to section Liparis. Further phylogenetic study based on combined molecular data from nrITS and plastid trnL-F ascertained its phylogenetic position as L. tsii being sister to L. sasakii and L. nanlingensis. A key to identification with the allied species is provided.  相似文献   

8.
Fragments from section 3 of the salivary gland X chromosome of D. melanogaster were dissected with a micromanipulator. The DNA was extracted, cut and ligated to a λ vector in a volume of a few nanoliters in an oil chamber monitored through a microscope. From about 10 pg of DNA we obtained 80 recombinant clones, a sample of which were analysed and shown to contain Drosophila DNA which hybridises in situ to the region of section 3 of the X chromosome. With this technique we can isolate clones from any desired region as small as 200 kb from the euchromatic arms of polytene chromosomes. This paper is dedicated to Professor W. Beermann on the occasion of his sixtieth birthday  相似文献   

9.
Primula jiugongshanensis J. W. Shao, a new species from Mt Jiugongshan in Hubei Province, China, is described and illustrated. This species is a biennial glabrous herb with pinnately compound leaves, and affiliated to P. sect. Ranunculoides C. M. Hu. It is distinguished from other species of the section by outer simple leaves ovate, flowers distylous, corolla lobe apex conspicuously emarginate, and lack of bulblets. Molecular phylogenetic analysis of nrDNA internal transcribed spacer sequences (ITS) was conducted and the results also supported the recognition of P. jiugongshanensis as a new species. The species is known from only three separated unprotected populations and is categorized as ‘Endangered’ (EN).  相似文献   

10.
11.
Immunogold labeling of cryosections according to Tokuyasu (Tokuyasu KT. A technique for ultracyotomy of cell suspensions and tissues. J Cell Biol 1973;57:551–565), is an important and widely used method for immunoelectron microscopy. These sections are cut from material that is chemically fixed at room temperature (room temparature fixation, RTF). Lately in many morphological studies fast freezing followed by cryosubstitution fixation (CSF) is used instead of RTF. We have explored some new methods for applying immunogold labeling on cryosections from high‐pressure frozen cells (HepG2 cells, primary chondrocytes) and tissues (cartilage and exocrine pancreas). As immunolabeling has to be carried out on thawed and stable sections, we explored two ways to achieve this: (1) The section fixation method, as briefly reported before (Liou W et al. Histochem Cell Biol 1996;106:41–58 and Möbius W et al. J Histochem Cytochem 2002;50:43–55.) in which cryosections from freshly frozen cells were stabilized in mixtures of sucrose and methyl cellulose and varying concentrations of glutaraldehyde, formaldehyde and uranyl acetate (UA). Only occasionally does this method reveal section areas with excellent cell preservation and negatively stained membranes like Tokuyasu sections of RTF material. (Liou et al.) (2) The rehydration method, a novel approach, in which CSF with glutaraldehyde and/or osmium tetroxide (OsO4) was followed by rehydration and cryosectioning as in the Tokuyasu method. Especially, the addition of UA and low concentrations of water to the CSF medium favored superb membrane contrast. Immunogold labeling was as efficient as with the Tokuyasu method.  相似文献   

12.
Lynn Bohs 《Biotropica》2000,32(1):70-79
The Witheringia solanacea complex consists of three species, W. asterotricha, W. meiantha, and W, solanacea, native to Central and South America. The three taxa are morphologically similar, and their distinctions and relationships have been the subject of taxonomic controversy. To investigate breeding systems and potential for hybridization among the taxa of the complex, two Costa Rican accessions per species were used in a crossing program. All plants were self‐incompatible except for one accession of W. solanacea. Hybrid plants resulted from all crosses among accessions of W. asterotricha and W. solanacea. Most crosses were unsuccessful using W. meiantha in combination with either of the other two taxa. It is suggested that W. meiantha and W. solanacea be recognized as separate taxa, but that W. asterotricha be considered a synonym of W. solanacea.  相似文献   

13.
王文采 《广西植物》2016,36(Z1):120-134
在该文中首次给出革叶楼梯草的雄头状花序描述; 还给出樱叶楼梯草雄头状花序的修正描述和兜苞墨脱楼梯草的修正特征集要; 写出托叶楼梯草和南川楼梯草二种的分类学修订,其中包括2新变种和2新等级; 描述了小叶楼梯草组的1新种和骤尖楼梯草组的3新种; 数年前被归并为异名的兜苞墨脱楼梯草和五肋楼梯草得到恢复。  相似文献   

14.
很多入侵植物具有克隆性,克隆整合对入侵克隆植物生长和繁殖具有重要的贡献。自然界中,植物生长和繁殖所需的各种资源如光照、水分和矿质养分等在空间上分布通常是异质的,但关于异质环境下克隆整合对入侵植物和本土同属植物种间关系影响的研究相对缺乏。通过温室控制实验,将入侵植物南美蟛蜞菊(Wedelia trilobata)和同属本土植物蟛蜞菊(W.chinensis)的分株对单独种植或者混合种植在异质性光照条件下,同时通过保持或者切断分株之间的连接来控制克隆整合效应的有无,研究异质光照环境下克隆整合对南美蟛蜞菊和蟛蜞菊种间关系的影响。克隆整合对南美蟛蜞菊和蟛蜞菊的生长和繁殖都有促进作用,且南美蟛蜞菊比蟛蜞菊从克隆整合中获益更多。与单独种植相比,两者混种对南美蟛蜞菊的叶生物量有显著影响,而对本地种蟛蜞菊的根生物量有显著影响。克隆整合和种间关系对南美蟛蜞菊的总生物量和叶生物量产生了显著的交互作用,而对蟛蜞菊各指标无显著影响。克隆整合状态显著影响了南美蟛蜞菊和蟛蜞菊的种间关系。这些结果表明,异质环境下克隆整合可以改变入侵植物南美蟛蜞菊和本土植物蟛蜞菊的生长性状及种间关系。  相似文献   

15.
Previously, we identified two closely related proteins termed W14 and W15 that were enriched in the overwinter buds of the gentian plant Gentiana triflora. Expression of the latter protein W15 has been implicated in its association with cold hardiness, because of its absence in a cold-sensitive mutant. Here, we characterized these two proteins and the genes encoding them. Amino acid sequences of the W14 and W15 proteins showed difference at only three amino acid positions, and both of them showed homologies to α/β hydrolase fold superfamily. Consistently, GST-fused W14 and W15 proteins expressed in bacteria showed hydrolase activity toward 1-naphtyl acetate. Structural analysis of these two genes in seven different gentian strains/cultivars including an anther culture-derived homozygous diploid revealed that W14 and W15 genes are allelic. Three genotypes were found; two strains carried both alleles (W14/W15), one carried the W15 genes in both alleles (W15/W15), and others were homozygous of W14 (W14/W14). Interestingly, expression of the two proteins exhibited allele-specificity. In one W14/W15 strain, expression of the W15 allele was almost repressed. In addition, organ specific expression of the alleles was observed in different cultivars. These observations were discussed in relation to winter hardiness of the gentian plants. Nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB281493 and AB281494.  相似文献   

16.
王文采 《广西植物》2018,38(8):969-972
该文描述了自云南西北部发现的毛茛科翠雀花属二新种:短葶翠雀花(Delphinium breviscaposum W.T.Wang)和丝苞翠雀花(D.filibracteolum W.T.Wang)。短葶翠雀花与察隅翠雀花(D.chayuense W.T.Wang)在亲缘关系上相近,前者与后者的区别在于短葶翠雀花植株具3条簇生短花葶,总状花序的轴和花梗无毛,小苞片较长,萼片较小,退化雄蕊的瓣片不分裂;丝苞翠雀花与拟长距翠雀花(D.dolichocentroides W.T.Wang)近缘,前者与后者的区别在于丝苞翠雀花的花组成圆锥花序,花梗、萼片和萼距均较短,退化雄蕊的爪无附属物,心皮无毛。  相似文献   

17.
Wiedemamia (s. str.) brevilamellata Wagner is proposed as replacement name for W. alpina Vaillant, 1953 not W. (Chamaedipsia) alpina Engel, 1918). W. beckeri glacicola Wagner replaces W. (Chamaedipsia) beckeri alpina Vaillant, 1967 (not Engel, 1981, not Vaillant, 1953).  相似文献   

18.
To evaluate the sectional classification in Carex, subgenus Vignea, the ITS region of 58 species of 20 sections was analyzed with Neighbor Joining (NJ) and Markov chain Monte Carlo (MCMC) methods. Sections Dioicae, Physodeae and Ovales are found to be monophyletic, with C. bohemica well integrated in the section Ovales. Section Heleonastes turns out to be monophyletic, if C. canescens is treated separately in section Canescentes. Section Elongatae is monophyletic, but C. remota is placed in section Remotae and C. bromoides in section Deweyanae. In both analyses, six representatives of section Arenariae cluster together in a terminal group, whereas C. disticha, C. repens and C. siccata form a basal cluster. C. maritima, as the only member of section Incurvae, shares this basal position. C. chordorrhiza is ascribed to section Chordorrhizeae and not ascribed to the paraphyletic section Divisae. C. vulpina and C. otrubae are assigned to section Vulpinae and separated from the heterogeneous section Stenorhynchae. The other members of sections Divisae, Muehlenbergianae, Multiflorae and Stenorhynchae are scattered throughout the trees. The representatives of section Foetidae are dispersed in both analyses, section Paniculatae appears to be non-monophyletic in the molecular results as well. The subgenus appears subdivided in at least four larger subgroups in all analyses. Whereas these subgroups are strongly supported, the relationships between these subgroups remain only poorly resolved.  相似文献   

19.
Wittrockiella is a small genus of filamentous green algae that occurs in habitats with reduced or fluctuating salinities. Many aspects of the basic biology of these algae are still unknown and the phylogenetic relationships within the genus have not been fully explored. We provide a phylogeny based on three ribosomal markers (ITS, LSU, and SSU rDNA) of the genus, including broad intraspecific sampling for W. lyallii and W. salina, recommendations for the use of existing names are made, and highlight aspects of their physiology and life cycle. Molecular data indicate that there are five species of Wittrockiella. Two new species, W. australis and W. zosterae, are described, both are endophytes. Although W. lyallii and W. salina can be identified morphologically, there are no diagnostic morphological characters to distinguish between W. amphibia, W. australis, and W. zosterae. A range of low molecular weight carbohydrates were analyzed but proved to not be taxonomically informative. The distribution range of W. salina is extended to the Northern Hemisphere as this species has been found in brackish lakes in Japan. Furthermore, it is shown that there are no grounds to recognize W. salina var. kraftii, which was described as an endemic variety from a freshwater habitat on Lord Howe Island, Australia. Culture experiments indicate that W. australis has a preference for growth in lower salinities over full seawater. For W. amphibia and W. zosterae, sexual reproduction is documented, and the split of these species is possibly attributable to polyploidization.  相似文献   

20.
青藏高原气候严酷,陆地表层生态系统脆弱,其高寒植物群落特征及生态系统生产力对气候变化的响应极其敏感。利用开顶箱(OTCs,Open Top Chambers)式装置在藏北高山嵩草(Kobresia pygmaea)草甸设置不同增温梯度实验(W1、W2、W3、W4),探究增温对高寒草甸植物群落特征及地上生产力的影响。研究结果表明:1)与对照样地相比,增温减少了植物群落总盖度(2015年,W1、W2、W3、W4分别显著减少了28%、23%、59%、60%; 2016年,W4显著减少了83%)和高山嵩草盖度(2015年,W1、W2、W3、W4分别显著减少了26%、33%、681%、64%; 2016年,W4显著减少了85%),而低幅度增温(W1、W2)对委陵菜属植物盖度无显著影响,高幅度增温(W3、W4)显著减少了委陵菜属植物盖度(2015年,W3、W4分别显著减少了58%和60%;2016年,W4显著减少了71%); 2)对整个植物群落而言,增温幅度较低时,增温对群落的生长和生物量的积累有促进作用,当温度升高超过一定程度,这种促进作用会逐渐减弱甚至变成抑制作用(2015年,W4显著减少了地上生物量69%; 2016年,W4显著减少了地上生物量82%); 3)高山嵩草盖度和其他物种总盖度存在显著的年际差异,而委陵菜属植物盖度无明显的年际变化。研究结果预示着,一定程度的升温会促进高寒草甸植物群落的生长,但温度升高超过一定幅度时,会导致草地生产力下降,草地退化加剧,同时当地群落中委陵菜属植物在全球变化背景下相对稳定,这类物种在未来气候变暖的背景下可能具有更强的竞争力。  相似文献   

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