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1.
Systematic wood anatomy of the tribe Guettardeae (Rubiaceae). The wood anatomy of nearly all genera of the Guettardeae (Rubiaceae, Guettardoideae) has been examined, and in this respect the tribe is heterogeneous. Suggestions are made for a delimitation of the tribe. Guettarda, Bobea, Antirhea, Malanea and Chomelia Jacq. are sufficiently similar in their wood anatomical characters to warrant retention in the same tribe. Machaonia, Timonius and Dichilanthe are anomalous. Suggestions are given for taxonomic revisions of some genera based on their wood anatomy.  相似文献   

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The present phytochemical investigations of Gardenia jasminoides Ellis resulted in the isolation of ten iridoids (110) and ten pyronane monoterpenoids (1120). Among them, compounds 11 and 18 were obtained from this species for the first time. The chemotaxonomic importance of these compounds was also summarized.  相似文献   

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We investigated the evolution of fruit characters, animals versus abiotic dispersal modes, life forms and geographical distribution, in the large, mostly tropical, family Rubiaceae. As a basis for our analysis we used a phylogenetic tree derived from chloroplast DNA variation. Fleshy fruits have evolved independently at least 12 times in the family. Most of these originations appear to have occurred during Eocene to Oligocene, i.e. the radiation period for some animal taxa (bird families, mammal orders) comprising most extant dispersers of Rubiaceae fruits. Changes of dispersal modes may be of more recent origin in a few cases, e.g. evolution of drupes in some lineages, and shifts from drupes to nuts. The distribution of fruit characters suggested that in several lineages animal-dispersed fruits, such as berries and drupes have remained largely unaltered since the time of origination. This is in contrast to the occurrence of winged seeds in capsules, and pterophylls, i.e. enlarged calyx lobes promoting wind dispersal of fruits, which apparently have shifted more frequently during evolution, indicating a difference in 'phylogenetic plasticity' between modes of animal and wind dispersal.
Animal dispersal was over-represented among genera dominated by shrubs, whereas abiotic dispersal was most prevalent among herbaceous genera. Drupes were over-represented in groups with transoceanic distributions, and on islands, indicating dispersal over long distances, probably by birds. In contrast, no evidence was found to support the view that animal dispersal in general enhances long distance dispersal. We also analysed geographical patterns on the tribal level but these were too complex to yield any resolved area cladograms due to the occurrence of many widespread taxa and area redundancy.  相似文献   

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? Premise of the study: Microsatellite primers were developed for a heterostylous herb, Hedyotis chrysotricha to investigate the effect of habitat fragmentation on its genetic diversity and population structure. ? Methods and Results: Twelve primer sets were developed and their polymorphisms were tested on 47 individuals from two island populations of H. chrysotricha in Thousand Island Lake of China. The number of alleles per locus ranged from five to 10, with an average of seven alleles. Expected heterozygosity per locus ranged from 0.284 to 0.821 and observed heterozygosity ranged from 0.191 to 0.851. ? Conclusions: We showed that all of the 12 microsatellite markers developed for H. chrysotricha are polymorphic within populations, which should provide a powerful tool for assessing population structure and genetic diversity across fragmented and continuous populations, and for studying the genetic effects of habitat fragmentation on this species.  相似文献   

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Chemical study of the aerial parts of Anthospermum emirnense led to the isolation of one original iridoid glycoside (1) along with six known iridoids (2–7), three lignans (8–10), two flavonoids (11–12), one coumarin (13), two anthraquinones (14–15), two benzoic acids (16–17) and three triterpenoids (18–20). These results are the first chemical data on non-volatile constituents of this genus. The chemotaxonomic significance of these compounds is discussed.  相似文献   

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卵叶茜草(茜草科)名称的后选模式指定   总被引:1,自引:0,他引:1  
根据对保存于西北植物研究所植物标本馆(WUK)的合模式标本进行研究,对卵叶茜草(Rubia ovatifoliaZ.Y.Zhang)的名称作出后选模式指定。  相似文献   

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对螺序草属(Spiradiclis B1、)16种2变型共18个样品的种子形态特征的初步研究表明,本属植物种子为小型(0.2—0、3mm)或中型(0.3—2mm),整体形状不太规则,表面纹饰为蜂窝状,种脐稍突出。种子的外壁由内外2层种皮组成。依据表面突起分布方式,螺序草属的种子大致分为2种类型:(1)平周壁微下陷,疣突均匀分布于其上,如大叶螺序草、螺序草、尖叶螺序草、柳叶螺序草、峨嵋螺序草和龙州螺序草;(2)平周壁下陷成穴状,突起分布在穴边缘,如红花螺序草、心叶螺序草、两广螺序草、广东螺序草、海南螺序草、宽昭螺序草、疏花螺序草、多枝螺序草、罗氏螺序草、小叶螺序草、石生螺序草和紫花螺序草。螺序草属的种子形态特征对属下类群的划分具有重要的参考价值。  相似文献   

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In this paper our previous chemical study of the anti-dengue active species Faramea bahiensis, Faramea hyacinthina and Faramea truncata (synonym of Faramea caudata) (Rubiaceae) is complemented by isolating from their stems, through a combination of silica gel and Sephadex LH-20 column chromatography and reversed-phase solid-phase extraction, the known iridoid glucosides monotropein (1), monotropein methyl ester (2) and 10-deacetylasperulosidic acid (3). The structures were established by HPLC-DAD-MS/MS analysis, NMR spectroscopy and comparison with literature data. This is the first report on the occurrence of these compounds in the genus Faramea Aubl. This work contributes to expand the knowledge of the chemical diversity of this botanical genus, of which a limited number of identified compounds have been reported.  相似文献   

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Ontogeny in Cotula australis, Leptinella dioica and L.pyrethrifolia confirms the presence of layers derived from the endosperm, testa and pericarp surrounding the embryo in mature cypselae in Asteraceae. The structure of mature cypselae of 24 species, representing all 12 genera that have been assigned to the 'Cotuleae', is reported. Several characters that appear to be relatively constant within genera or groups of genera are identified as providing information on affinities above the generic level. The data support the conclusion that the 'Cotuleae' is an unnatural assemblage: Cotula, Leptinella, Nananthea and Soliva appear to form one close-knit group, and Dimorphocoma, Elachanthus and Isoetopsis another, while the remaining genera are highly diverse. The first group appear to be good members of the Anthemideae. Evidence is provided to support the placement of the second group in the Astereae near Minuria. Cypsela characters support the placement of Plagiocheilus near Solenogyne.  相似文献   

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MADS-box转录因子的相互作用及对果实发育和成熟的调控   总被引:3,自引:0,他引:3  
刘菊华  徐碧玉  张静  金志强 《遗传》2010,32(9):893-902
MADS-box基因编码的蛋白是一类数目庞大的转录因子家族, 通过与其他转录因子相互作用形成同源或异源二聚体, 调控着整个植株的生长发育。文章对近年来MADS-box转录因子的相互作用及对果实发育和成熟的调控作用的研究进展进行了综述, 为了解MADS-box转录因子的作用方式和作用机理及深入研究MADS-box基因对调控果实发育和成熟的作用提供参考。  相似文献   

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根据对保存于湖南师范大学生命科学学院植物标本馆(HNNU)、中国科学院华南植物园植物标本馆(IBSC)、中国科学院昆明植物研究所植物标本馆(KUN)和中国科学院植物研究所植物标本馆(PE)的茜草科(Rubiaceae)蛇根草属(Ophiorrhiza Linn.)标本的研究,将金黄蛇根草(Ophiorrhiza aureolina Lo f. aureolina)和绿春蛇根草(O. luchunensis Lo)处理为变红蛇根草(O. subrubescens Drake)的新异名。  相似文献   

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Aim In Madagascar the family Rubiaceae includes an estimated 650 species representing 95 genera. As many as 98% of the species and 30% of the genera are endemic. Several factors make the Rubiaceae a model system for developing an understanding of the origins of the Malagasy flora. Ancestral area distributions are explicitly reconstructed for four tribes (Knoxieae, Naucleeae, Paederieae and Vanguerieae) with the aim of understanding how many times, and from where, these groups have originated in Madagascar. Location Indian Ocean Basin, with a focus on Madagascar. Methods Bayesian phylogenetic analyses are conducted on the four tribes. The results are used for reconstructing ancestral areas using dispersal–vicariance analyses. Phylogenetic uncertainties in the reconstructions are accounted for by conducting all analyses on the posterior distribution from the analyses. Results Altogether, 11 arrivals in Madagascar (one in Paederieae, five in Knoxieae, three in Vanguerieae, and two in Naucleeae) are reconstructed. The most common pattern is a dispersal event (followed by vicariance) from Eastern Tropical Africa. The Naucleeae and Paederieae in Madagascar differ and originate from Asia. Numerous out‐of‐Madagascar dispersals, mainly in the dioecious Vanguerieae, are reconstructed. Main conclusions The four tribes arrived several times in Madagascar via dispersal events from Eastern Tropical Africa, Southern Africa and Tropical Asia. The presence of monophyletic groups that include a number of species only found in Madagascar indicates that much endemism in the tribes results from speciation events occurring well after their arrival in Madagascar. Madagascar is the source of origin for almost all Rubiaceae found on the neighbouring islands of the Comoros, Mascarenes and Seychelles.  相似文献   

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Damnacanthus , Lasianthus, Saldinia, and Trichostachys are also included. Wood anatomical characters are compared with recent phylogenetic insights into the study group on the basis of molecular data. The observations demonstrate that the delimitation and separation of several taxa from the former Coussareeae/Morindeae/Prismatomerideae/Psychotrieae aggregate is supported by wood anatomical data. The Coussareeae can be distinguished from the other Rubioideae by their scanty parenchyma, septate libriform fibres, and the combination of uniseriate and very high multiseriate rays with sheath cells. Axial parenchyma bands and fibre-tracheids characterise Gynochtodes and some species of Morinda (Morindeae s.str.), but the latter genus is variable with respect to several features (e.g. vessel groupings and axial parenchyma distribution). Wood data support separation of Rennellia and Prismatomeris from Morindeae s.str.; vessels in both genera are exclusively solitary and axial parenchyma is always diffuse to diffuse-in-aggregates. Damnacanthus differs from the Morindeae alliance by the occurrence of septate fibres, absence of axial parenchyma, and the occasional presence of fibre wall thickenings. There are interesting similarities between members of the Lasianthus clade and the Pauridiantheae/Urophyleae group such as the sporadic occurrence of spiral thickenings in axial parenchyma cells. Received 26 January 2001/ Accepted in revised form 6 June 2001  相似文献   

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林祁 《植物研究》2007,27(3):267-268
由于同时指定两号标本为模式,桦木科(Betulaceae)的九龙桦 (Betula jiulungensis Hu ex P. C. Li)和茜草科(Rubiaceae)的卵叶茜草(Rubia ovatifolia Z. Y. Zhang)是不合格发表的名称。现通过分别指定主模式,对九龙桦和卵叶茜草的名称作合格发表。  相似文献   

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The pollen morphology of 38 representative species and varieties within the genus Coffea L. is described. Eight pollen types, placed in two major groups, have been identified on the basis of the number of colpi, colpus characteristics, exine morphology and pollen size. Differences in pollen structures of the species studied do not correspond to present taxonomic groupings, but support a current proposal to place some of the species in the genus Paracoffea Leroy. Among the four sections in the genus, the section Eucoffea contains a high degree of pollen polymorphism.  相似文献   

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利用光学显微镜和扫描电镜研究了茜草科粗叶木属Lasianthus 16种2亚种、1变种及相关的5属5种的花粉形态。粗叶木属的花粉属于广孢型, 单粒。一般中等大小, 绝大多数为圆球形, 少数为近长球形或长球形。花粉形态特征, 特别是在萌发孔和外壁纹饰上表现出多样化。根据孔沟的数目或是否具有内孔, 可以将萌发孔分为(3-)4-(-5)孔沟和3孔。在所观察的这些种中, 萌发孔以3-4孔沟为主要类型, 比例为62.4%。外壁纹饰可分为细网状、粗网状和穴状。有部分种的花粉极面有穴状纹饰, 其余均为网状纹饰。网眼一般椭圆形、近圆形、三角形或者不规则形。少数外壁纹饰网脊上有颗粒状雕纹或模糊的颗粒, 网脊轮廓线呈波浪形, 一般凸出且平滑。大部分种的花粉具有沟膜, 沟膜上具有瘤状突起或小颗粒状, 沟边缘一般较平滑, 或粗糙, 有的种具有沟桥。  相似文献   

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