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1.
A comprehensive study on nutlet morphology on 46 taxa from the tribe Elsholtzieae was conducted using stereomicroscopy, light microscopy and scanning electron microscopy. The objectives were to evaluate the nutlet characteristics in a systematics context and to provide additional evidence for taxon delimitation. The nutlet shape varied from elliptical, widely elliptical, spheroidal and ovate to pyriform. The size ranged from 0.50 to 2.70 mm in length and 0.34 to 2.65 mm in width. The three types of trichomes included simple non-glandular trichomes (Collinsonia punctata), clavate non-glandular trichomes (Elsholtzia cephalantha) and peltate glandular trichomes (Mosla grosseserrata and M. chinensis). We also report the presence of a mucilaginous reaction in nine species of the genus Elsholtzia in Elsholtzieae for the first time. Four types (undulate, papillae-like projection, thorn-like pattern and reticulate) and three subtypes (reticulate, reticulate-cellular and supra-reticulate) of nutlet surface patterns in the mid-ventral region were recognized in Elsholtzieae based on the differences in cell outline, outer periclinal walls and dentations of the anticlinal walls. These nutlet micromorphological results may serve as a reference for future hypotheses on the classification of the tribe Elsholtzieae.  相似文献   

2.
Morphological and micromorphological characters of the nutlets of ten Onosma species in Turkey were reported. Studied fruit surfaces show some variations. Based on the structure and patterns of epidermis cells of the nutlets, two principal types can be distinguished. In Type 1, the epidermal cells of the nutlet surface are formed in a reticulate pattern with varied sizes and shapes of the meshes. This type is the most common type in the studied species. Seven of the species observed belong to the reticulate type, i.e. O. bracteosum, O. mutabile, O. aleppicum, O. bornmuelleri, O. aucheranum, O. araraticum and O. tauricum. In Type 2, the epidermal cells of the nutlet surface are formed in an elongated type with varied sizes and shapes. Three of the observed species belong to this type, i.e. O. roussaei, O. isauricum and O. stenolobum. Significant taxonomic differences between species were determined on the surface of the nutlets.  相似文献   

3.
4.
Cytological studies were carried out on 14 taxa belonging to Amitostigma , Chusua , Galearis , Habenaria , Hemipilia , Hemipiliopsis , Herminium , Peristylus and Ponerochis , collected mostly from the south-eastern part of the Hengduan Mountain Region, south-west China. Cytological data on 11 of the taxa are reported for the first time. The interphase nuclei were either of the simple chromocentre type or intermediate between simple and complex chromocentre types. The nuclear morphology of Hemipiliopsis at interphase supports the conclusion that it is related more closely to Chusua and Ponerochis than to Habenaria . At the whole tribe level, however, the results did not indicate a clear correlation between morphological features of the interphase nuclei and phylogeny. The somatic chromosome numbers were 2 n  = 42 in ten species and 2 n  = 32, 38, 40, 64 and 72 in four species. The chromosome counts of 2 n  = 32 and 64 in Habenaria aitchsonii are rare in the genus. It is proposed that the repeated change of chromosome number from x  = 7 to x  = 8 has played an important role in the evolution of the tribe Orchideae. This change has occurred mainly in the European subtribe Orchidinae, but also in the Asian subtribe Habenariinae.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 231–238.  相似文献   

5.
In this study, we comparatively investigated three endemic Salvia species spreading in Erzincan (Turkey) in terms of anatomy and micromorphology. For anatomical investigation, cross sections taken from stems and leaves of the species were examined under light microscope. For micromorphological investigation, epidermal surface and nutlet structure were examined using scanning electron microscopy. The S. euphratica and S. divaricata species were examined anatomically and micromorphologically for the first time, and S. hypargea was examined micromorphologically for the first time. In anatomical examinations, it was seen that stem and leaf structures of the species were similar. In micromorphological analyses, it has been seen that hairiness of the nutlet surface and nutlet ornamentations (verrucate and rugose type) created a difference between the species.  相似文献   

6.
Morphological characters of the nutlets of Cyclotrichium Manden. & Scheng. in Turkey were examined using scanning electron microscopy (SEM). The genus Cyclotrichium is represented by six species in Turkey, of which two are endemic for Turkey. Nutlet morphology of the species was studied using stereoscopic microscopy and SEM, and the features were described and illustrated. Nutlet morphology of the examined specimens exhibits some variation in size, shape and sculpture. Nutlets range from 1.1 to 2.0 mm in length and 0.5 to 1.0 mm in width and are elliptic, oblong to ovoid and trigonous in shape. Nutlet sculpture can be divided into two main types: distinctly or weakly reticulate pattern in C. niveum, C. origanifolium, C. longiflorum and rounded cell arrangement in the remaining species. Micromorphological characters could be useful in solving taxonomic problems of Cyclotrichium.  相似文献   

7.
Trichomes of 26 species of Alcea (Malvaceae) were investigated using light (LM) and scanning electron microscopy (SEM). The trichomes show a great micromorphological variation, which provides data useful for species delimitation in Alcea. Two basic types of trichomes could be distinguished in Alcea and allied genera: glandular and eglandular. The glandular trichomes could in turn be subdivided into two subtypes: capitate and clavate. The eglandular trichomes could be subdivided into five subtypes: simple, fascicled, stellate, fascicled-stellate and pluri-radiate. Characters of taxonomic interest are: trichome density (glabrous to dense), number of arms per trichome, orientation relative to the epidermal surface (appressed to erect) and presence/absence of a stalk. According to the results the species of Alcea can be divided into four informal groups based on trichome types. The results further support the exclusion of the annual Althaea species from the perennial ones and their close relationship to Malva. In addition, a close relationship between perennial Althaea and basal Alcea lineages is supported. Based on the evolutionary framework provided by recent molecular phylogenetic investigations, the following trends can be observed in the Malva alliance: long and narrow-armed trichomes are primitive in relation to short and thick-armed trichomes; dense indumentum coverage is primitive in relation to moderately dense or glabrous ones; presence of simple hairs on stem (particularly on leaves) is more advanced than their absence; spreading villous-stellate and fascicled trichomes are more advanced than appressed stellate ones. Clavate trichomes, which were found exclusively in a few species of Alcea, should be considered as a derived state in relation to capitate ones, and they may provide a synapomorphy for the crown group of Alcea.  相似文献   

8.
The taxonomic value and evolutionary significance of 30 leaf epidermal characters from 238 samples representing 127 species of all seven genera in the tribe Gaultherieae (Ericaceae) and two outgroup genera were investigated by scanning electron microscopy. The character states were coded and optimized onto a maximum‐likelihood tree based on previous molecular data with Fitch parsimony and hierarchical Bayesian analysis to trace the evolution of character states throughout all internodes in the phylogenetic tree for Gaultherieae. Leaf epidermal characters were found to be largely consistent within species, but highly variable at interspecific and higher taxonomic levels. The most recent common ancestral states of 15 characters diagnosed various lineages recovered from prior studies, some with no prior morphological support. Relatively high frequencies of state change occur in the eastern Asian clade Gaultheria series Gymnobotrys + Diplycosia, the American clade G. subsection Dasyphyta p.p., the core East Asian clade and the Australia/New Zealand clade. The characters with the highest frequencies of state change are the outer stomatal ledge ornamentation type, the stomatal apparatus level, stomatal density and area, and the type of abaxial trichomes. These character state change patterns may provide insight into the ecological adaptions of Gaultherieae during their evolutionary history. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 686–710.  相似文献   

9.
REJDALI M., 1991. Leaf micromorphology and taxonomy of North African species of Sideritis L. (Lamiaceae). This study reports on the structure of trichomes, epidermal cells, stomata and venation patterns. The trichomes are either glandular or eglandular. The latter are unicellular or multicellular, soft or rigid pointed hairs. The glandular hairs are short or long stalked, the latter are generally flattened and may be sessile. The epidermal cells are variously shaped with sinuous or straight walls usually randomly orientated. Stomata are either anomocytic or diacytic and evenly distributed throughout the epidermis without any definite pattern of orientation. Venation is of the semicraspedodermous type.  相似文献   

10.
Tiquilia is very different from the other members of the Ehretiaceae (Boraginales) in many aspects of morphology and ecology. Because detailed knowledge about flower and fruit traits is necessary to reliably infer character evolution of and within Tiquilia, we investigated flower to fruit ontogeny in eight species of Tiquilia using light and electron microscopy. Tiquilia accumulated a number of autapomorphies such as the prostrate growth form, the lack of lateral and ventral bundles in the gynoecium, and the formation of nutlet‐like mericarpids as dispersal units instead of more or less succulent drupes. The internal architecture of the superior bicarpellate ovary resulted from the development of several secondary septa including apical, basal and false septa, as it has been reported also from other Boraginales. However, no character found in Tiquilia can be regarded as synapomorphic with any other taxon of the Ehretiaceae. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 112 , 520–534.  相似文献   

11.
Variation in foliar trichomes in Croton (Euphorbiaceae) is reviewed, and the terminology clarified by redefinitions and illustrations of terms. Evolution of trichome types appears to proceed from branched (stellate or fasciculate) hairs to simple and dendritic ones. A systematic enumeration characterizes the trichome morphology in 36 of the 40 sections, with citation of the 120 species examined.  相似文献   

12.
果皮和种皮微形态特征在杜鹃花属系统学研究中的应用   总被引:12,自引:0,他引:12  
采用扫描电子显微镜对国产杜鹃花属Rhododendron6个亚属的代表种和近缘类群杜香属Ledum杜香L.palustre的果皮和种皮微形态特征进行观察,对杜鹃花属植物果皮微形态特征进行了系统描述,并通过比较现存杜鹃花属植物和种子化石,新发现一些居间的种子类型。结果表明,果皮和种皮微形态特征具有一定的系统学意义。叶状苞亚属subgen.Therorhodion的叶状苞杜鹃R.redowskianum的果实有短而疏的刺毛,无气孔,种子为无翅类,扁平,外围轮廓长椭圆形。杜鹃亚属subgen.Rhododendron植物果皮为百合花杜鹃型,具有鳞片,气孔器散生于指状突起之间,与叶表皮的微形态特征一致,其种子为百合花杜鹃型,表面具宽而浅的沟,呈脑纹状,有别于无鳞类杜鹃花。常绿杜鹃亚属subgen.Hymenanthes果皮为云锦杜鹃型,其角质层表面不规则,无表皮毛,偶见气孔;种子为云锦杜鹃型。映山红亚属subgen.Tsutsusi果皮为岭南杜鹃型,密生长表皮毛,角质层致密;种子为南边杜鹃型和岭南杜鹃型。微形态特征与“常绿杜鹃亚属和(国产)映山红亚属均为内部支持率很高的单系类群”的分子系统发育研究结果一致。马银花亚属subgen.Azaleastrum的马银花组sect.Azaleastrum和长蕊杜鹃组sect.Choniastrum微形态区别明显,支持各自为独立的单系类群。羊踯躅亚属subgen.Pentanthera的羊踯躅R.molle果皮特征明显,可与其他亚属区分,但种子类型更接近常绿杜鹃亚属。本研究结合分子系统发育资料和叶表皮微形态特征讨论了一些近缘类群的系统发育关系;研究结果支持将腺萼马银花处理为独立的种。  相似文献   

13.
The leaf anatomy of the subtribe Hyptidinae (Labiatae), which consists of four small genera and the largr genus Hyplis , is dercribed. The leaves may be dorsiventral or isobilateral. Variable characters of the lainina include: frequency and forms of trichomes, cuticular markings, presence of adaxial stoinata, thickness of leaf, thickness of adaxial epidermis, presence of a hypodermis, occurrence of sclcrified tissues (especially sclerified bundle sheath extensions, phloem and xylem fibres), mesophyll structure and venation pattern. Petiole vasculature varies from simple to complex, sometimes with medullary traces present. Most of the variable characters are related to xeromorphy and are tax-onomically useful within the framework of the present classification.  相似文献   

14.
A new species of Veronica vadiniense in section Veronica is described from material from the Cantabrian Range, in the north-east of the province of León (north-west Spain). Several morphological characters related to stems, leaves, racemes, flowers and capsules are given, and also those related to the indumentum of different parts of the plant, especially calyx lobes and capsule. Indications about distribution and habitat with reference to bioclimatic, biogeographical and phytosociological aspects are provided. Diagnostic features are also given to enable comparison with the most similar species, Veronica officinalis and V. allionii , particularly in the indumentum and consistency of leaves, and in the indumentum and shape of the capsule.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 119–124.  相似文献   

15.
Leaves from the tribe Banksieae of the Proteaceae are well represented in Tertiary deposits in south-eastern Australia. Four new species of Banksieaephyllum are erected, taking the total to 11, and two species are described in a new genus, with leaves with architectural similarities to the tribe Banksieae but without organic preservation. The fossil species demonstrate that the tribe was diverse by the end of the Eocene, but it is difficult to determine the ancestral type from the fossil evidence at present. The vegetation associated with some of the fossil species suggests that the tribe may have had its origins in rainforest, and became adapted to the typically dry, nutrient-poor conditions of sclerophyllous vegetation during the course of the Tertiary.  相似文献   

16.
The generic classification of moths of the tribe Macariini Guenée is reviewed critically, and a revised classification is presented. The review is based on a survey of species across the taxonomic and geographical range of the tribe. In the new framework, the number of genera is reduced considerably. Two genera are very large: Macaria Curtis (mainly New World) and Chiasmia Hübner (largely Old World) together include over half of all macariine species. Twenty-three genera are accepted in the tribe; the identity of two genera remain uncertain. No single character defines the tribe, but diagnostic features include one or more of the following: the presence of enlarged setae ('horns') on the uncus in the male genitalia; a divided valva; and a modified condition of sternum A8 in the male. The taxonomic history of the tribe is reviewed briefly and the problems of previous systems are explained mainly by the regional approach adopted. A diagnosis is presented for each genus. © 2002 The Linnean Society of London, Zoological Journal of the Linnean Society , 2002, 134 , 257–315.  相似文献   

17.
The classification of the genera of the widely distributed Old World tribe Pseudoterpnini is reviewed and 34 genera are recognized. Two new generic synonyms ( Sterictopsis Warren and Oxyphanes Turner as synonyms of Rhuma Walker), and 21 new or reinstated combinations are established. Representative moths of all the genera are illustrated in colour (upper side and underside), and genitalia of all genera are illustrated in monochrome (162 figures). All the known species and subspecies of Pseudoterpnini are listed (321), together with their synonyms. The Pseudoterpnini and their characters are assessed, and many genera are newly assigned to the tribe.  © 2007 Natural History Museum, London. Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 343–412.  相似文献   

18.
分类学是认识生物体的一种工具,对生物体间系统关系的理解,种质资源利用的指南,也是一种交流用的普通语言.因此,分类处理需要反映这些关系的近期认识.在自然界,生物体只有两个绝对的单位:个体与种.一个种是一群个体被不可缺少的生殖关系相互联系成为的一个绝对单位.生殖隔离是种与种间的基本界限,同时也是生物演化过程中形成独立基因库(gene pools)的惟一因素.既然在种以上的分类群没有绝对界线,在种以上的任一分类处理都不可能避免人为性.虽然如此,仍然必须作出某些分类适应它们的描述、利用与(或)研究.这篇文章对小麦族分类群间生物系统关系的划分是基于遗传学的研究.我们分类处理的原则是:(1)反映这些种系统演化现今的理解;(2)便于种质资源的利用;(3)避免与传统处理有不必要的剧烈改变.  相似文献   

19.
毛茛科升麻族植物药用亲缘学初探   总被引:1,自引:0,他引:1  
本文总结和归纳了在北美、欧洲以及亚洲广泛应用的毛茛科Ranunculaceae升麻族Cimicifugeae药用植物的系统分类、传统药用价值、现代药理以及化学成分研究结果,并在此基础上初步探讨了该族植物的药用亲缘学关系.升麻族药用植物主要含有9,19-阿尔廷烷三萜皂苷以及肉桂酸衍生物两大类化合物.升麻族植物在传统药用中被用来镇痛、解毒、抗炎,在北美很早就被印第安人用来治疗妇科疾病.现代药理研究发现升麻族植物还具有抗骨质疏松、抗病毒、抗肿瘤、抗过敏、类雌激素样作用等.通过对升麻族植物药用亲缘学的初步研究,我们发现由于类叶升麻属Actaea和升麻属Cimicifuga的疗效和化学成分相近,因此两属的亲缘关系也近.考虑它们果实的形态差异,以及细胞学特征不同,认为这两属为升麻族植物的一个分支,且以类叶升麻属较升麻属更为进化.从化学分类学的角度来看,铁破锣属Beesia含有特殊铁破锣皂苷可以成为一个独立的分支,而黄三七属Souliea既和铁破锣属一样含有五环三萜和铁破锣型环阿尔廷烷三萜类化合物,又和升麻属、类叶升麻属一样含有吲哚生物碱,因此可以认为它是铁破锣属和升麻属、类叶升麻属之间的一个过渡类型.升麻族植物特有的清热解毒功效与其特殊的阿尔廷烷三萜皂苷化学成分密切相关,因此我们认为阿尔廷烷三萜皂苷可以作为抗肿瘤、抗病毒的新药源进一步深入研究.  相似文献   

20.
Nearly 60 species from the genera Euphorbia L. and Elaeophorbia Stapf were investigated for diterpenes of the classes tiglianes, ingenanes and ortho-esters. The diterpenes were isolated as their acetates by a micro-technique from latex or fresh herb material collected from several countries around the world. Authentication of the diterpenes was by chromatographic means using spectroscopic methods as back-up data. These compounds were absent from only 9% of the species examined. The most commonly occurring diterpene was ingenol, followed closely by 12-Deoxy phorbol. The ingenane derivative 5-Deoxy-ingenol was always detected as a minor companion to ingenol from species of the section Tithymalus. Species of the section Euphorbium contained mainly the diterpene ingenol although both tigliane and ortho-ester diterpenes were also present in some species. Species from the sections Anisophylhtm and Poinsettia did not contain diterpenes of the type in question, whilst species from the genus Elaeophorbia yielded ingenol. These results provide additional chemical evidence concerning recent suggestions on the subgeneric and generic status of Anisophyllum, Poinsettia, Tithymalus and Elaeophorbia.  相似文献   

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