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1.
利用光镜和扫描电子显微镜首次对安徽母草属(Lindernia)六种植物的花粉形态进行了观察研究.结果表明该属花粉粒多为近球形, 具3 沟, 表面光滑.探讨了花粉形态特征的分类学意义,支持属级水平的分类.  相似文献   

2.
The aim of this review article is to present, for the first time, an appraisal of the phytochemical, ethnobotanical and pharmacological data on Bunium species. The literature search was conducted using the Scopus, Google Scholar and PubMed databases. The genus Bunium has been found to produce both essential oil (EO), mainly comprising monoterpenes and sesquiterpenes, and non-volatile components mainly coumarins and flavonoids. There are several pharmacological activities associated with the Bunium species, especially antioxidant, antibacterial and antifungal properties. The chemotaxonomic appraisal of the phytochemical pattern of the genus is in sink with the current classification of the family. Moreover, this review confirms the significant ethnobotanical and pharmacological potential of different Bunium species.  相似文献   

3.
The phytochemical content of the Mediterranean species of the Sideritis genus has been reviewed. The components included in this review are monoterpenes, sesquiterpenes, diterpenes, triterpenes, sterols, flavones, coumarins and phenylpropanoids. From the chemotaxonomic point of view, we have divided the species from this region into four groups. The first of this is formed by taxa containing triterpenes, but not diterpenes. A second group is constituted by species having bicyclic diterpenes of the labdane type and not diterpenes. The third group is characterized by its content in tetracyclic diterpenes of the ent-kaurene type. A fourth group is composed of plants with tetracyclic diterpenes of the ent-beyer-15-ene and/or ent-atis-13-ene class. In addition, the relations of these Mediterranean species with those of the Macaronesian region have been examined.  相似文献   

4.
Czernaevia Turcz. is a monotypic genus in the Umbelliferae, tribe Peucedaneae, with the only species Cz. laevigata Turcz. occurring in northern East Asia. Although the species has often been included in Angelica L., and sometimes even in Ostericum Hoffm., the present study indicates that it is distinct not only in having dimorphic petals, but also in its fruit structure, pollen morphology and phytochemical components. The fruit has numerous, compressed vittae, the pollen grains are not constricted at the equatorial region with a small P/E ratio (1.7-2.1), and neither coumarins nor flavonoids have been found to be present at significant level in the species. It is taxonomically probably rather isolated and the monotypic genus Czernaevia is tenable.  相似文献   

5.
The genus Gaultheria has been classified into ten sections (one with two subsections) and 22 series of which five are new combinations and 21 are new taxa. Seven of these sections are composed primarily of solitary flowered species and the other three sections of racemose species. About half of the species of the genus are included in section Brossaea. A summary of the classification is here presented.  相似文献   

6.
From the whole plant of Aconitum gymnandrum Maxim., four diterpene alkaloids have been isolated and identified: talatizamine, 14-acetyltalatizamine, condelphine and isotalatizidine. Thus the species nvestigated, belonging to the monotypic subgenus Gymnaconitum (Stapf) Rapaics, secms to be phytochemically closely related to A. nemorum M. Pop. and A. talassicum M. Pop. From the phytochemical point of view however, A. gymnandrum does not seem to be the most advanced species within the genus Aconitum.  相似文献   

7.
Abstract The genus Cathaya discovered in Kwangsi, Sichuan, Hunan and Guizhou is endemic in China. Only one species (C. argyrophylla Chun et Kuang) has so far been known in the genus. The question on it’s systematic position in the family Pinaceae has been much debated. However, according to some taxonomists and morphologists, this genus is related to genera Pinus, Picea and Pseudotsuga of the Pinaceae. No phytochemical data, especially of serratene components on Cathaya have been recorded. This paper deals with the systematic position of Cathaya in Pinaceae based on seven known components of serratene family which are isolated from the trunk of Cathaya argyrophyua growing in Sichuan. A comparative study on serratene components of Cathaya with other genera ofPinaceae showed that Cathaya is related to genera Pinus and Picea.  相似文献   

8.
Abstract

A comparative study was performed to identify and classify traditional Chinese medicines (TCMs) of the genus Clematis by applying chemometric and numerical methodologies. In the analysis, 12 species representing major TCM plants of the genus and belonging to five different sections – Rectae, Clematis, Meclatis, Tubulosae and Viorna – were identified and demarcated on the basis of morphological and phytochemical characters. In the numerical study (NS), out of 53 selected characters, only 27 phylogenetically informative characters were used for data generation; a phenogram was produced with three distinctive clades. The extent of genetic distances ranged from 0.35 to 0.80. The phytochemical analysis (PA) was conducted using a high performance liquid chromatography coupled with a diode array detector (DAD) and ESI‐MS mode. The compound “Huzhangoside D” (HGD) was the most abundant in the analysed species of the genus. The PA of saponins produced a differential matrix based on the presence or absence of chemical characters, which generated a phenogram. The extent of genetic distances ranged from 0.05 to 0.35 in the phytochemical analysis, with three distinctive clades. Clematis intricata had compounds (HGB, HGD) with GD 0.30, and produced a different pattern of clustering than the previous classification system. The species C. henryi and C. heracleifolia appeared as sister clades having congruent genetic similarity with each other; this is an innovative combination. The classification results of PA and NS approaches corroborate each other, but the chemical fingerprinting method proved more authentic, quick and reliable for the identification and classification of these plant taxa.  相似文献   

9.
中国茶藨子属的研究   总被引:11,自引:0,他引:11  
通过对国产茶藨子属的形态、分类和地理分布的研究,笔者支持把该属置于虎耳草科的观点,不赞成把它分离作为独立的科。另外,认为Rehder系统中所划分的4个亚属较合理,故予以采纳,但笔者对其中的亚属、组和系的划分、各分类类目的内容、系统排列的顺序等诸方面都作了较大修订。从系统发育的观点出发,对亚属的排列次序则和Rehder系统有很大不同,而对组和系的范围及其系统位置也作了较大改动。中国茶藨子属植物初步确定为59种30变种,隶属于4亚属10组15系(包括5新系)。依据对茶藨子属分布区的分析,首次提出了东亚区是茶藨子属植物的现代分布中心,在东亚区中,中国-喜马拉雅森林植物亚区中的横断山脉地区和中国-日本森林植物亚区的西部是茶藨子属发生和发展的关键地区。  相似文献   

10.
林有润 《植物研究》1996,16(4):405-412
本文初步考证了《本草纲目》中菊科植物,计有44属、78种、2变种。  相似文献   

11.
The presence of several phytochemicals, namely naphthodianthrones hypericin and pseudohypericin, phloroglucinol derivatives hyperforin and adhyperforin, the phenolic acids as chlorogenic acid, neochlorogenic acid, caffeic acid and 2,4-dihydroxybenzoic acid, the flavonols, hyperoside, isoquercitrin, quercitrin, quercetin, avicularin, rutin, and flavanols (+)-catechin and (?)-epicatechin, as well as biflavonoid amentoflavone was investigated in seven Turkish species of Hypericum from Taeniocarpium and Drosanthe sections. Plants were harvested at flowering, dried at room temperature, dissected into different tissues and assayed for chemical contents by HPLC. All chemicals were detected at various levels depending on species and plant parts. Despite the observed quantitative variation in the chemical content of plant material, it was found that phytochemical profiles of the species from the same section were very similar. The present data could be helpful in selecting the future targets for phytochemical and biological studies as well as enriching our current chemical knowledge about Hypericum species. Such kind of data could also be useful for elucidation of the chemotaxonomical relationships among the sections of Hypericum genus.  相似文献   

12.
锦鸡儿属植物分布研究   总被引:25,自引:1,他引:24  
周道玮 《植物研究》1996,16(4):428-435
依据每个种的地理分布范围,确定了出六种分布类型,并编制了属的分布密度图。结合各类发布特点及其形态特征,认为东亚西南部为其起源中心,而中亚来其变异分化中心。起源第三纪中期的原始类群Ser.Caragana,在寒旱主要压力下分化适应,形成现代化布格局。  相似文献   

13.
The genus Dichocarpum is endemic to East Asia, and many species have been used to treat various diseases. However, phytochemical researches of this genus have been limited to date. In the present study, a metabolomic approach based on UPLC-Q-TOF-MS/MS was used to explore the phytochemical profiles of 10 Chinese Dichocarpum species, and cannabinoid receptor (CB1/CB2) agonistic activities evaluation of these plants was performed. A total of 128 features were putatively annotated, belonging to alkaloids, flavonoids, triterpenes saponins, phenolic acids, and others. Semi-quantitative statistics demonstrated that alkaloids and flavonoids were widely distributed, with the former the most abundant, whereas triterpenes saponins were mainly distributed in D. fargesii and D. wuchuanense. The phylogenetic results obtained from DNA sequencing assigned the 10 species to three groups. Further results of in silico annotation revealed three chemical families and helped determine the characteristic features of the three groups. In addition, the plant extracts of nine species from this genus showed agonistic activity on CB2 receptors. This comprehensive analysis revealed the chemotype distribution and pharmacophylogenetic relationship, to provide clues for the prospective resource utilization of the medicinal plants from the genus Dichocarpum.  相似文献   

14.
15.
The American genus Cuphea with ca. 260 species is extremely diverse with respect to chromosome number. Counts are now available for 78 species and/or varieties, or 29% of the genus. Included in this study are first reports for 15 taxa from Brazil, Cuba, Dominican Republic, Mexico, and Venezuela. Twenty-two different numbers are known for the genus, ranging from n = 6 to n = 54. The most common number in the primary center of species diversity in Brazil is n = 8, which is regarded as the base number of the genus. Two numbers are most common in the secondary center in Mexico, n = 10 and n = 12. Species with n = 14 or higher are considered to be of polyploid origin. Polyploids comprise 46% of the total species counted and appear in 9 of the 11 sections for which chromosome numbers have been reported. Aneuploid species comprise ca. 25% of the genus and are known from 7 of the 11 sections. The two subgenera are not characterized by different chromosome numbers or sequences of numbers. None of the 14 sections are circumscribed by a single chromosome number. Morphological and ecological variability in widespread, weedy species is correlated with differing chromosome numbers in some species whereas in others the chromosome number is stable. Summary of chromosome numbers by taxonomic section is presented. Section Euandra, centered in eastern Brazil, and the largest section of the genus, appears to be chromosomally most diverse. In section Trispermum, characterized by difficult, variable species with intermediate forms, two of the four species studied have polyploid races. Section Heterodon, endemic to Mexico and Central America and comprising most of the annual species of the genus, is best known chromosomally. Chromosome numbers have been counted for 25 of 28 species, and 12 different numbers are reported. The most advanced sections, Melvilla and Diploptychia, with numerous species occurring at higher altitudes, are characterized by high polyploids. Apomictic species occur in sect. Diploptycia. The cytoevolution of Cuphea is complex with frequent polyploid and aneuploid events apparently playing a significant role in speciation in both centers of diversity.  相似文献   

16.
Evolution of reproductive systems in the genus Silene   总被引:2,自引:0,他引:2  
The genus Silene contains both hermaphrodite, gynodioecious and dioecious species, dioecy being represented in three sections of the genus. To locate the events of change of reproductive systems, we compared ITS sequences of 22 species of Silene chosen throughout the whole genus, and four putative outgroup species. Gynodioecy, which is the most common reproductive system within the genus Silene and in closely related genera such as Saponaria and Dianthus, is proposed to be ancestral in the genus. Dioecy has evolved at least twice: once in the section containing S. latifolia, and once in the clade containing S. otites and S. acaulis ssp. bryoides. Evolution towards hermaphroditism, associated with evolution of selfing has also occurred at least twice, in S. gallica and S. comica.  相似文献   

17.
BACKGROUND AND AIMS: The genus Bupleurum has long been recognized as a natural group, but its infrageneric classification is controversial and has not yet been studied in the light of sequence data. METHODS: Phylogenetic relationships among 32 species (35 taxa) of the genus Bupleurum were investigated by comparative sequencing of the ITS region of the 18-26S nuclear ribosomal DNA repeat. Exemplar taxa from all currently accepted sections and subsections of the genus were included, along with outgroups from four other early branching Apioideae genera (Anginon, Heteromorpha, Physospermum and Pleurospermum). RESULTS: Phylogenies generated by maximum parsimony, maximum likelihood, and neighbour-joining methods show similar topologies, demonstrating monophyly of Bupleurum and the division of the genus into two major clades. This division is also supported by analysis of the 5.8S coding sequence alone. The first branching clade is formed by all the species of the genus with pinnate-reticulate veined leaves and B. rigidum with a unique type of leaf venation. The other major clade includes the remaining species studied, all of which have more or less parallel-veined leaves. CONCLUSIONS: These phylogenetic results do not agree with any previous classifications of the genus. Molecular data also suggest that the endemic Macaronesian species B. salicifolium is a neoendemic, as the sequence divergence between the populations in Madeira and Canary Islands, and closer mainland relatives in north-west Africa is small. All endemic north-west African taxa are included in a single unresolved but well-supported clade, and the low nucleotide variation of ITS suggests a recent radiation within this group. The only southern hemisphere species, B. mundii (southern Africa), is shown to be a neoendemic, apparently closely related to B. falcatum, a Eurasian species.  相似文献   

18.
While plants of the genus Dyssodia are used by man to a certain extent, few phytochemical and pharmacological studies have been performed with species of this genus. D. tagetiflora is an endemic plant of Mexico and has been used as fodder. The aim of this research was to isolate and identify the main bioactive components and evaluate the insecticidal, antioxidant, genotoxic and cytoprotective activities of D. tagetiflora. The isolated substances included an essential oil composed of six monoterpenes, and extracts containing two flavonols, three flavonol‐glycosides and four thiophenes. The compounds were characterized using spectroscopic and spectrometric methods, including GC/MS, MS and NMR. The essential oil showed insecticidal activity against Drosophila melanogaster larvae. The methanolic extract of D. tagetiflora (DTME) had strong antioxidant activity against DPPH and ABTS radicals; DTME showed no evidence of genotoxic or cytotoxic effects. In contrast, DTME showed a cytoprotective effect attenuating the formation of H2O2‐induced micronuclei in Vicia faba roots. This report is the first to describe the phytochemical and biological activity of D. tagetiflora.  相似文献   

19.
The first classification for the genus Ormosia was proposed by Bentham. It was followed by Taubert (1892) in Engler and Prantl’s Nat. Pflanzenf., who divided the genus into 2 sections. On the basis of the pod structure and seed characters Prain (1900) arranged the genus in 2 sections with 4 subsections. In the monograph on the genus Merrill and L. Chen ( 1943 ) limited their taxonomic study to Chinese and Indo-Chinese species, and recognized 34 species and 15 series. Recently Yakovlev (1971-1976) has treated the genus in 6 separate genera. In the present paper the author recognizes 35 species, of which 7 species and 2 varieties are new. The Chinese species of the genus are grouped into 3 sections and 6 series inmy classification.  相似文献   

20.
The present article is the first comprehensive treatment of phytogeography of Thermopsis (Fabaceae) in the world. Thermopsis is one of the few genera within Fabaceae with the distribution pattern of the East Asia-North American disjunction. The distribution patterns of 5 recognized sections (including a new one) covering 21 species in Thermopsis are analyzed, and the results show four centres of frequency of the genus: the Eastern Asiatic Region (9 spp. / 3 sects., including 4 endemic species), the Irano-Turanian Region (7 spp./3 sects., including 3 endemic species), the Rocky Mountain Region (7 spp./2 sects., all endemic), and the Atlantic North American Region (3 spp. / 1 sect., all endemic). In the light of the fact that most species and sections, a number of phylogenetic series of the genus, and the most primitive sections and most advanced sections in Thermopsis occur in the East Asia, the Eastern Asiatic Region might be the centre of diversity of the genus. As the Irano-Turanian Region and the Rocky Mountain Region were just second to that of Eastern Asiatic Region in number of sections and species, and many polyploids appeared in these regions, they were considered as the secondary centres of distribution and speciation of the genus. The speciation looks to be frequent and complex in these regions, and many new taxa have been described from there while many new reduced or incorporated taxa have happened over there. However, recent molecular data has shown that two reduced taxa of Thermopsis are distinct in these regions. Based on the modern distribution patterns and evolutionary trends in morphological characters of the genus, and available fossil record of the genus and the historical geology, we speculate that Thermopsis had already existed on Eurasia and North America before the Late Miocene, and probably originated from an ancestral form of Sophora-like taxa with lupine alkaloids somewhere in the Laurasia in the Early Tertiary or Late Cretaceous. After the separation of the two continents, species on different continents developed distinctly under influences of different evolutionary factors. In Asia, the late Tertiary orogeny, disappearing of the Tethys and aridity and freezing caused by the Quaternary glaciation were the main forces to promote the speciation and evolutionary processes, whereas in North America it was the Quaternary glaciation and the orogeny of partial area to promote evolution of the genus. According to the evolutionary trends in Thermopsis and the distribution pattern of the primitive taxa, Sino-Japanese Subregion of Eastern Asiatic Region may be considered asthe centre of primitive forms of Thermopsis.  相似文献   

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