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1.
A survey of A-type transfer cells in leaves of 118 species representing 87 genera and 3 5 tribes of Leguminosae-Papilionoideae suggests that their presence or absence is taxonomically predictable both at tribal level and in terms of major series of tribes. Members of 'pulvinate' (tropical) tribes generally lack transfer cells, while 'epulvinate' (temperate) forms commonly possess them.  相似文献   

2.
The cuticles of twenty-four species from a wide range of mono- and di-cotyledonous plants were examined by chemical methods. The cuticles differ markedly in the amount and composition of the surface wax, in the thickness of the cuticular membrane, and in the content and composition of the cutin of the membrane. Fruits usually have heavier wax deposits and much thicker membranes than leaves. No direct relationship exists between surface waxiness and thickness of the membrane. Alkanes and primary alcohols are prominent in many of the surface waxes; triterpenoids occur less frequently. The cutin content of the membrane varies considerably; a delicate membrane tends to have a low content of cutin in which fatty acids are prevalent, and a well-developed membrane a higher content of cutin more rich in hydroxy-fatty acids. 10,16-Dihydroxyhexadecanoic acid is often an important constituent of cutin; 9,10,18-trihydroxyoctadecanoic acid is most prominent in the cutin of thicker membranes. The possible influence of the variations in cutin acids upon the structure of cutin and the taxonomic implications of wax and cutin composition are discussed.  相似文献   

3.
A detailed morphological and anatomical study of the tropical African genus Virectaria is presented. The observations are used to characterize the genus, to propose a key to all eight species, and to unravel the relationships between the species using cladistics. A taxonomic survey of the genus is also given. Verdcourt's infraspecific taxa based on calyx morphology in V major are adopted, but it was found that morphological distinction is correlated with ecological, habit and distributional differences. Hence, it is better to recognize Verdcourt's varieties spathulata and major as subspecies of V. major. The problematic systematic position of the genus is discussed in detail. New evidence is given for the exclusion of the genus from the Hedyotideae and Ophiorrhizeae (subfamily Rubioideae). The recently proposed position in the Sabiceeae (subfamily Ixoroideae) is not convincing either, since none of the genera included in the Sabiceeae matches Virectaria with respect to pollen, fruit, flower and growth habit. Exclusion from the Rubioideae and a position near the Sabiceeae is supported by lack of raphides, seed anatomy, placentation, stipule morphology and molecular evidence. Molecular data from a larger number of taxa are needed to confirm the position of the genus.  相似文献   

4.
The paper summarizes all accepted species and subspecies of the generaPetasites andEndocellion, together with important synonyms, type quotations, main diacritical characters, and an outline of their distribution. The new taxa described in this study are as follows: subgen.Capillopetalum, sect.Cricostigma, sect.Schistostigma, sect.Trichostigma, sect.Sceptrostigma, further ser.Japonici, ser.Orientales, ser.Fragrantes, ser.Spurii, ser.Imberbes, ser.Sagittati, and subspeciesPetasites frigidus subsp.sibiricus. New combinations:Petasites radiatus (J. F. Gmel.),P. rubellus (J. F. Gmel.)P. hybridus subsp.georgicus (Manden.),P. nivalis subsp.vitifolius (L. E. Greene),P. nivalis subsp.hyperboreus (Rydb.),P. palmatus subsp.speciosus (Nutt.),Endocellion sibiricum (J. F. Gmel.) andE. glaciale (Ledeb.).  相似文献   

5.
This paper provides a general survey of the occurrence of diterpenes in the Asteraceae. Data on 4351 botanical occurrences were obtained from the literature. These were grouped by skeleton for each genus. Then, the genera were grouped by subtribes, which, in turn, were gathered in tribes, followed by subfamilies. In spite of the low number of species containing diterpenes, it was possible to describe some structural features of these compounds, i.e. the skeletal types in various taxa and the positions in some skeletons that are always oxidized or never undergo oxidation in some genera. Thus, it was verified that: in the subfamily Cichorioideae, only a few of the studied species possess diterpenes, wherein kaurane is the most frequent diterpene skeleton. In the Asteroideae, the presence of diterpenes is much greater than that in the Cichorioideae and Carduoideae. At tribal taxonomic level, for example, the Astereae produce labdanes and clerodanes; Heliantheae and Eupatorieae produce kauranes and labdanes, respectively; and Calenduleae produce pimaranes. Some taxonomic implications are presented.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 291–308.  相似文献   

6.
RICE, E. L., 1989. A statistical morphological analysis and taxonomic revision of the genus Xiphophora (Fucaceae). Xiphophora is a brown seaweed endemic to the cool temperature rocky shores of Australia and New Zealand. The two species, X. chondrophylla and X. gladiata have previously been separated by morphological criteria. However, the differences betweeen them in these characters were largely size-related, resulting in taxonomic confusion. In particular, the presence of X. gladiata in New Zealand has been disputed. In this study, a series of discriminant function analyses were performed, based on a suite of morphological characters collected from each species throughout a major portion of their geographic ranges. The results show conclusively that the present taxonomy of Xiphophora is untenable. This genus is composed of two species, but these are distributed latitudinally (either side of the 40oS parallel). Each species contains two allopatric subspecies; one in Australia and the other in New Zealand. A formal taxonomic revision of the genus is presented.  相似文献   

7.
Parthenocissus (the Virginia creeper genus, Vitaceae) consists of 13 species and shows a disjunct distribution between Asia and North America. We investigated the inflorescence structure, calyx morphology, appendages on the inner side of petals, leaf epidermis, pollen and seed characters throughout the genus. A combined phylogenetic analysis with 27 morphological and 4137 molecular characters was conducted and the result was largely congruent with that of the previous molecular work, but with higher resolution. The combined analysis identified two clades corresponding to the Asian and North American taxa. Parthenocissus feddei was resolved as closely related to the clade containing P. cuspidifera, P. heterophylla and P. semicordata. The four species share synapomorphies of having conspicuously raised veinlets, an obscurely five‐ (to eight‐) lobed calyx, appendages on the inner side of petals covering the entire length of anthers and foveolate pollen exine ornamentation. Within the Old World clade, the pentafoliolate species were weakly supported as more closely related to species with both simple and trifoliolate leaves. Furthermore, the ancestral states of tendril apices, inflorescence structure, appendages on the inner side of petals and exine ornamentation of pollen grains were reconstructed on the molecular strict consensus tree. The appendages on the inner side of petals and exine ornamentation of pollen grains were suggested to be important characters in the taxonomy of Parthenocissus, especially for species with trifoliolate leaves. Finally, the previous classifications of Parthenocissus were evaluated within the phylogenetic framework. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, ?? , ??–??.  相似文献   

8.
Vascular anatomy was examined in leaves ofBotrychium andHelminthostachys belonging to the Ophioglossaceae. A median split or constriction of bundles was observed in pinna- and pinnule-supplies in several species ofBotrychium, as well as in the bundles of the stalk (as dichotomy II), and the interpretation of the shoot as a series of dichotomies is criticized in this study. Variations of vascular anatomy inBotrychium subgenus Sceptridium do not indicate that the so-called phyllomophores and rhizomes are homologous. Although critical anatomical evidence for evolutionary trends in the origin of pinna-supplies could not be obtained, simplification from extramarginal origin to marginal origin receives supporting evidence from morphological characteristics of the leaves.  相似文献   

9.
Leaves of 97 taxa representing all the genera at present recognized in the family Oleaceae were surveyed for flavonoids. Four flavonol glycosides were found to be common, the 3-glucmides and 3-rutinosides of quercetin and kaempferol, as were four flavone glycosides, namely the 7-glurosides arid 7-rutinosides of luteolin and apigenin. Among rarer constituents detected were luteolin 4'-glucoside, eriodictyol 7-glucoside, chrysoeriol 7-glucoside, an apigenin-di-C-glycoside and several higher glycosides of quercetin. The species and genera surveyed fell into two groups: those with flavonol glycosides alone; and those with both flavonol and flavone glycosides. The most striking correlation was with chromosome number (and subfamily division) since almost all taxa with a basic number of 11, 13 and 14 had only flavonol glycosides, whereas most taxa with x = 23 had both types of flavonoid. Evolutionary advancement in the family appears to involve the gradual replacement of flavonol by flavone glycosides. Indeed, a few tam, notably Nestegis apelala, Picconia excelsa and Tesserandra fluminense , lacked flavonol glycosides in the leaves completely. At the lower levels of classification, the distribution of flavonoids is of less interest. However, the patterns in Linociera and Chionanthus , two taxa recently made congeneric, are sufficiently different to suggest that this decision might have to be reconsidered when more is known of their chemistry. Otherwise leaf patterns generally fit in with the existing generic classification in the family.  相似文献   

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Early changes in fine structures of intracellular organelles ofSaintpaulia leaves exhibiting chilling-induced degeneration of photosynthetic activities were investigated by electron microscopy. As early as 3 min after exposure to 10C water, thylakoid lamellae in the palisade cells showed extensive disarrangement, especially in intergrana lamellae. Simultaneously, other organelles showed drastic morphological changes, including the condensation of chromatin in the nucleus.  相似文献   

15.
Leaf glucosinolates of 42 Diplotaxis and 21 Eruca accessions were studied. Total content ranged from 0.25 to more than 70 g kg(-1) dry wt. The 13 clusters, defined on the basis of glucosinolate composition, belonged to two glucosinolate-rich groups, characterised by the prevalence of a single component, and one low-glucosinolate group, with a profile not dominated by any individual component. A sinigrin-rich cluster (D. ibicensis, D. berthautii, D. ilorcitana, D. siettiana, D. tenuisiliqua, D. brevisiliqua, and D. virgata) and a gluconapin-rich cluster (D. catholica, D.siifolia, D. virgata, and D. ollivieri) included all the species previously classified in the nigra phylogenetic lineage. D. virgata was confirmed to be a critical taxon, with one accession slightly diverging from the others. D. siifolia subsp. vicentina was separated from the others in a glucobrassicin-rich cluster. D. harra, a rather isolated representative of sub-genus Hesperidium, clustered together D. assurgens in a sinalbin-rich cluster. Another well defined cluster was represented by D. brachycarpa (gluconasturtin). The two sub-species of D. erucoides were well differentiated by their glucosinolate profile. The low glucosinolate species: D. tenuifolia, D. viminea, D. cretacea, D. muralis (subgenus Diplotaxis), and E. vesicaria, all previously included in the rapa/oleracea lineage, belonged to seven less defined clusters, mainly differing on the presence/absence or the relative abundance of some components (glucoraphanin, glucolepidin, 4-hydroxy-glucobrassicin, 4-phenylbutyl gls, glucoerucin and neoglucobrassicin). The data support previous taxonomic works. Glucosinolate-rich taxa, with well characterised profiles may be suitable for industrial uses, whereas the variability of edible D. tenuifolia and E. vesicaria may represent a basis for breeding horticultural types.  相似文献   

16.
Leaves of 344 species of the Ericaceae and of 37 species in three related families have been surveyed for flavonoids and simple phenols. The yellow flavonol gossypetin was found in 158 ericaceous species and is of chemotaxonomic interest within the Rhododendroideae (where it occurs in 11 of 19 genera) and in the Vaccinioideae (in 3 of 22 genera). 5-0-methylflavonols appear in 81 species, again mainly in the Rhododendroideae (eight genera); whereas 3,5-di-O-methylquercetin, caryatin, is present only in Bejaria, Phyllodoce and Rhododendron. Dihydroflavonols. common in Rhododendron , show a sporadic distribution elsewhere in the family. Of the simpler phenols surveyed, gentisic acid is common but methyl salicylate is present mainly in Gaultheria. Hydroquinone appears in ten related genera, methylhydroquinone in three and orcinol in seven. The chemical evidence generally supports Stevens' recent classification of the family, particularly his inclusion of Epigaea in the Rhododendroideae and his transfer of Diplarche from the Diapensiaceae to the Ericaceae. There is also chemical evidence to support the separation of Calluna and Cassiope , the inclusion of the Aibutoideae within the Vaccinioideae and the retention of the Pyroloideae and Monotropoideae within the Ericaceae. In addition, chemistry indicates that Phyllodoce should be placed nearer to the Rhodoreae than in Stevens' system and that Cassiope and Harrimanella , placed together in the Cassiopeae by Stevens, are distinctly different.  相似文献   

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印度蔊菜(Rorippa indica)与无瓣蔊菜(R. dubia)的分类关系仍存在较大争议, 为阐明二者的分类学关系, 本研究综合利用形态指标测量、DNA相对含量检测、体细胞染色体观察和基于SSR分子标记的遗传距离分析等方法, 系统地比较了二者的分类学特征和细胞遗传学差异。结果表明: 印度蔊菜(2n = 48)为六倍体, 无瓣蔊菜(2n = 32)为四倍体。同时, 前者DNA相对含量约为150, 是后者的1.5倍。通过45对SSR分子标记的遗传距离分析得出, 相对于球果蔊菜(R. globosa)与欧亚蔊菜(R. sylvestris), 二者亲缘关系较近, 独立聚类为一支, 但在遗传距离为0.23处可以明确划分为两个种。同时, 利用角果长度和结籽密度两个形态指标可以将二者明显区分为两个种。另外, 二者存在明显的生殖障碍, 通过正反交授粉实验得出: 印度蔊菜与无瓣蔊菜自花授粉的结实率分别为97.73%和95.65%, 而以印度蔊菜为母本的杂交处理结实率为0, 以无瓣蔊菜为母本的杂交处理结实率为47.06%, 但其种子萌发率为0。综上所述, 印度蔊菜与无瓣蔊菜为两个种。  相似文献   

19.
Mature seeds of 109 species of Pedicularis representing 13 groups according to Tsoong’s infra-generic classification were investigated using light microscopy (LM) and scanning electron microscopy (SEM). The largest seeds occurred in P. superba (4.82 ± 0.32 mm × 2.18 ± 0.18 mm) and the smallest in P. crenata (0.95 ± 0.16 mm × 0.72 ± 0.08 mm). The individual seed weight ranged from 0.20 to 9.52 mg. There were two types of primary ornamentation, i.e. reticulate and undulate. Reticulate seeds were found in all examined species except for P. pantlingii and P. confluens. The reticulate seeds were divided into three subtypes, i.e. cristate-reticulate, regular-reticulate and membranous-reticulate. Among them, the cristate-reticulate and the undulate primary ornamentation are firstly reported. The inner tangential wall ornamentation was categorized into granulate, ruminate or striate. Seed characters seem to support the transfer of Pedicularis to Orobanchaceae from traditional Scrophulariaceae. Seed length, individual seed weight, primary ornamentation and inner tangential wall ornamentation were considered as potentially useful characters for infra-generic classification. Non-metric multidimensional scaling (NMDS) analyses indicated a clustering of some species in group 1 (Sceptrum) and all species in group 6 (Cyathophora), respectively. However, seed data were not highly congruent with Tsoong’s classification for delimitation of existing groups. Some characters, such as seed shape, primary ornamentation, inner tangential wall ornamentation and epidermal cell shape could be applied to identification of some species in this genus.  相似文献   

20.
Based on a complex study of morphology of adults, male and female genitalia, functional musculature of male genitalia, and molecular characters, three subgenera were distinguished in the genus Cania: the nominative one, Paracania Solovyev subgen. n. (type species Neaera bilinea Walker, 1855), and Minicania Solovyev subgen. n. (type species C. minuta Holloway, 1986). The genus Cania presently includes 21 species, two of which are described as new ones: C. (Paracania) lourensi Solovyev sp. n. (Philippines: Luzon, Negros, Panay) and C. (Minicania) kitchingi Solovyev sp. n. (Thailand). New synonymies are established: C. bilinea (Walker, 1855) = C. polyhelixa Wu et Fang, 2009 syn. n. and C. robusta Hering, 1931 = C. pseudobilinea Wu et Fang, 2009 syn. n.  相似文献   

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