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1.
Tropaeolum tuberosum Ruiz & Pav. (Tropaeolaceae) and its two subspecies, subsp. tuberosum and subsp. silvestre Sparre are described and illustrated, and their cultivation and propagation discussed. The origin of the cultivar ‘Sidney’ is noted.  相似文献   

2.
Tropaeolum leptophyllum G. Don subsp. gracile (Hook. & Arnott) Sparre is described and illustrated. The history and distribution in the wild of the two subspecies of T. leptophyllum are discussed and notes on cultivation are given.  相似文献   

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Gynostemma pentaphyllum, a member of family Cucurbitaceae, is a perennial creeping herb used as a traditional medicinal plant in China. In this study, six polymorphic nSSR and four EST‐SSR primers were used to genotype 1,020 individuals in 72 wild populations of G. pentaphyllum. The genetic diversity and population structure were investigated, and ecological niche modeling was performed to reveal the evolution and demographic history of its natural populations. The results show that G. pentaphyllum has a low level of genetic diversity and high level of variation among populations because of pervasive asexual propagation, genetic drift, and long‐term habitat isolation. Results of the Mantel test demonstrate that the genetic distance and geographic distance are significantly correlated among G. pentaphyllum natural populations. The populations can be divided into two clusters on the basis of genetic structure. Asymmetrical patterns of historical gene flow were observed among the clusters. For the contemporary, almost all the bidirectional gene flow of the related pairs was symmetrical with slight differences. Recent bottlenecks were experienced by 34.72% of the studied populations. The geographic range of G. pentaphyllum continues to expand northward and eastward from Hengduan Mountains. The present distribution of G. pentaphyllum is a consequence of its complex evolution. Polyploidy in G. pentaphyllum is inferred to be polygenetic. Finally, G. pentaphyllum is a species in need of protection, so in situ and ex situ measures should be considered in the future.  相似文献   

5.
In traditional Chinese medicine, Gynostemma pentaphyllum (Thunb.) Makino is a herbal drug of extreme versatility and has been extensively researched in China. The dammarane saponins isolated from Gynostemma pentaphyllum, namely gypenosides or gynosaponins, are believed to be the active components responsible for its various biological activities and reported clinical effects. This review attempts to encompass the available literature on Gynostemma pentaphyllum, from its cultivation to the isolation of its chemical entities and a summary of its diverse pharmacological properties attributed to its gypenoside content. Other aspects such as toxicology and pharmacokinetics are also discussed. In vitro and in vivo evidence suggests that Gynostemma pentaphyllum may complement the popular herbal medicine, Panax ginseng, as it also contains a high ginsenoside content and exhibits similar biological activities.  相似文献   

6.
Genetic variation was investigated using AFLP markers in 12 populations of Anthurium sinuatum and A. pentaphyllum var. pentaphyllum (Araceae) in north‐east Brazil, Amazonia and the Brazilian Atlantic forest. Two unique genetic patterns characterized the populations of A. sinuatum as a group, but no correlation between genetic and geographical interpopulation distance was found; the Amazonian population was not separated from that in Ceará. The isolated Ceará brejo populations of A. sinuatum were genetically distinct, but genetic diversity levels were similar to populations elsewhere, with no evidence of genetic erosion. Anthurium pentaphyllum populations were significantly different from each other; Bayesian genetic structural analysis found no common genetic pattern, but revealed genetic clusters unique to subgroups and individual populations in the Atlantic forest and French Guiana. Anthurium pentaphyllum and A. sinuatum can be distinguished genetically, but individuals of both species formed intermediate genetic clusters that blurred their distinction. We suggest that genetic mixing of A. sinuatum and A. pentaphyllum has occurred in north‐east Brazil, possibly connected with cycles of humid forest expansion. The weak genetic structure in A. sinuatum is consistent with the natural fragmentation of continuous forest areas, possibly during the Holocene. This study highlights the scientific importance of the highly threatened brejo forests for tropical American biogeography. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 88–105.  相似文献   

7.
Arnan X  Rodrigo A  Retana J 《Oecologia》2011,167(4):1027-1039
Strong interactions between dry-fruited shrubs and seed-harvesting ants are expected in early successional scrubs, where both groups have a major presence. We have analysed the implications of the seed characteristics of two dry-fruited shrub species (Coronilla minima and Dorycnium pentaphyllum) on seed predation and dispersal mediated by harvester ants and the consequences of these processes on spatio-temporal patterns of plant abundance in a heterogeneous environment. We found that large C. minima seeds were collected much more (39%) than small D. pentaphyllum seeds (2%). However, not all of the removed seeds of these plant species were consumed, and 12.8% of the seeds were lost along the trails, which increased dispersal distances compared with abiotic dispersal alone. Seed dropping occurred among all microhabitats of the two plant species, but especially in open microhabitats, which are the most suitable ones for plant establishment. The two plant species increased their presence in the study area during the study period: C. minima in open microhabitats and D. pentaphyllum in high vegetation. The large size of C. minima seeds probably limited the primary seed dispersal of this species, but may have allowed strong interaction with ants. Thus, seed dispersal by ants resulted in C. minima seeds reaching more suitable microhabitats by means of increasing dispersal distance and redistribution among microhabitats. In contrast, the smaller size of D. pentaphyllum seeds arguably allows abiotic seed dispersal over longer distances and colonization of all types of microhabitats, although it probably also limits their interaction with ants and, consequently, their redistribution in suitable microhabitats. We suggest that dyszoochory could contribute to the success of plant species with different seed characteristics in scrub habitats where seeds are abundantly collected by seed-harvesting ants.  相似文献   

8.
A field-based comparative study of leaflet outline shape in five populations of Anthurium sinuatum Benth. ex Schott from Amazonia and humid brejo forests of Ceará, Northeast Brazil, and ten populations of A. pentaphyllum (Aubl.) G. Don var. pentaphyllum from Amazonia and the Brazilian Atlantic forest is reported. 1,120 leaflets from 561 individuals in 15 populations were sampled. Using images, leaflet outlines were captured by digitisation and subjected to Elliptic Fourier Analysis (EFA) to produce matrices of Fourier coefficients based on 40 harmonics; lateral and central leaflets were analysed separately. Twelve shape variables, extracted from the Fourier coefficient matrices, described the leaflet outlines of 531 individuals. Between-population relationships were estimated using cluster analysis, Canonical Variates Analysis and non-parametric MANOVA. Amazonian populations showed the greatest within-population variability. In A. sinuatum the Pacatuba population was the most distinct in Ceará and the Pará population (Amazonia) was not significantly different from those at Ibiapaba and Maranguape (both Ceará). In A. pentaphyllum 80% of population pairs were significantly different and three significantly different groups of populations were observed. Although the populations of A. pentaphyllum displayed considerable variation, the morphological patterns did not correlate with previously reported molecular ones. The two species were found to be slightly but significantly different on leaf outline data.  相似文献   

9.
Sophora cassioides (Phil.) Sparre, from Chile, is illustrated and suggestions for its cultivation are given. The history of Sophora sect. Edwardsia is discussed briefly.  相似文献   

10.
以药食两用植物绞股蓝为材料,研究了植物激素乙烯对绞股蓝皂苷生物合成关键酶基因表达及皂苷含量的影响.该文采用荧光定量PCR技术,检测了乙烯利处理后绞股蓝不同器官中皂苷生物合成关键酶基因GpFPS、GpSS和GpSE的表达水平;采用分光光度法及HPLC技术,测定了乙烯利处理对绞股蓝总皂苷和皂苷单体Rb1、Rb3和Rd含量的...  相似文献   

11.
The species of Tropaeolum sect. Chilensia Sparre, are discussed. Their phytogeography, ecology, evolution and pollination are considered. Photographs of habitats, and of most of the species taken in the wild, are shown. A synopsis of all the species in the section, and a new arrangement of subsections is provided.  相似文献   

12.
SD 大鼠自由饮用绞股蓝汁(绞股蓝汁每天新鲜配制,浓度为每100 g 水2 g 茶叶,100℃的水温浸泡30 min,取上清液),连续给药60 d,取出肝脏,用差速离心法制备肝脏胞浆液及肝脏微粒体,采用双光束紫外分光光度法测定 CYP3A、CYP2E1、NADPH-细胞色素 C 还原酶、UGT、GST 的活性及细胞色素 b5的含量,结果显示绞股蓝可显著升高细胞色素 b5的含量,显著诱导 CYP3A、UGT、GST、NADPH-细胞色素 C 还原酶的活性,但对 CYP2E1没有影响。提示绞股蓝与药物合用时,在体内可能会发生代谢性药物相互作用。  相似文献   

13.
A rare maple from western Sichuan, Acer pentaphyllum Diels, is described and illustrated. Accounts of its original discovery, history in cultivation and recent rediscovery in the wild are given. The threats to its survival in the wild and its conservation in cultivation are discussed.  相似文献   

14.
以中草药植物绞股蓝[Gynostemma pentaphyllum(Thunb.) Makino]为化感供体材料,研究其不同浓度的提取液(0、5、10、25、50 g/L)对蛋白核小球藻(Chlorella pyrenoidesa)生长及生理生化特征的化感效应。结果表明:(1)绞股蓝提取液对蛋白核小球藻生长均具有抑制作用,其抑制作用随提取液质量浓度增大和培养时间延长均呈增强趋势,且25 g/L绞股蓝提取液培养15 d时的抑制率达到最大(79.41%)。(2)各浓度绞股蓝处理组蛋白核小球藻细胞内的叶绿素a含量均低于对照组,且随着提取液浓度升高以及处理时间延长叶绿素a含量较对照的降低量越多,表明蛋白核小球藻光合作用受到的影响也越大。(3)绞股蓝处理组蛋白核小球藻细胞的膜透性(吸光度OD_(264))显著高于对照,且膜透性随着提取液浓度增大而增强;高浓度提取液处理下,藻细胞内部的可溶性蛋白质(OD_(280))及核酸(OD_(260))含量均显著高于对照,且随着处理时间延长,细胞膜透性增大,细胞内部的可溶性蛋白质及核酸向胞外渗透增多。研究发现,绞股蓝提取液能够抑制蛋白核小球藻生长,并随着提取液质量浓度增大而增强;绞股蓝提取液能促进藻细胞叶绿素分解、增加细胞膜透性,引起可溶性蛋白质和核酸向胞外渗透量升高,导致藻细胞结构受损,代谢功能紊乱,从而达到化感抑制作用。  相似文献   

15.
Abstract

A report about new or interesting plants in the Marche region. III. — The authors report about the occurrence in the Marche of 61 entities of specific or infraspecific rank, 22 of which are new or unpublished concerning the region, while the remaining 39 have been previously very little or imprecisely mentioned; as to the latter new localities and stations are shown or general information on the distribution over the Marche district has been supplied. Out of the first 22 entities, 18 (Fumaria muralis subsp. muralis, Cardamine flexuosa, Lunaria annua subsp. pachyrhiza, Colutea arborescens subsp. gallica, Astragalus monspessulanas subsp. illyricus, Cornus sanguinea subsp. australis, Galium verrucosum, Hedypnois rhagadioloides subsp. tubaeformis, Andryala tenuifolia, Sonchus asper subsp. glaucescens, Rheichardia picroides var. maritima, Podospermum canum, Scorzonera austriaca, S. hirsuta, Bidens frondosa, Guizotia abyssinica, Ambrosia elatior, A. trifida) are, as far as the authors know, quite new or unpublished concerning the Marche, while 4 (Rumex angiocarpus, Trifolium repens subsp. prostratum, Epilobium lanceolatum, Picris hieracioides subsp. spinulosa) are generally reported in Middle Italy or over the whole Italian territory by the general Floras, but till now have not been mentioned in works dealing with regional flora.  相似文献   

16.
Arabidopsis halleri represents an important model species for the study of phytoremediation. In the Carpathians it is represented by three subspecies: A. halleri subsp. halleri, A. halleri subsp. tatrica and A. halleri subsp. dacica. All three subspecies are diploid with chromosome number 2n = 16. They differ mainly in indument of flower parts, colour of petals and in the position of the longest leaf on stem. A. halleri subsp. halleri occurs in the Eastern and Southern Carpathians and in the northern and eastern part of the Western Carpathians, subsp. tatrica is endemic of the Western Carpathians and subsp. dacica occurs in the Eastern and Southern Carpathians most probably extending in its distribution further to the south to the Balkan mountains. Full synonymy of these three taxa and also a fourth European subspecies, A. halleri subsp. ovirensis is presented including the information on type specimens. Lectotypes are selected for several names. List of the examined herbarium specimens is given as well.  相似文献   

17.
The yellow‐flowered everlasting daisy Helichrysum italicum (Asteraceae, Gnaphalieae) is widely distributed in the Mediterranean basin, where it grows in continuous and widespread populations in diverse open habitats. Helichrysum italicum subsp. microphyllum has a disjunct distribution in the Balearic Islands (Majorca and Dragonera), Corsica, Sardinia, Crete and Cyprus. Numerous morphological intermediates between subsp. italicum and subsp. microphyllum are known from Corsica, where the two subspecies co‐occur. The aims of the study were to investigate if subsp. microphyllum has a common origin, constituting an independent gene pool from subsp. italicum, or if the morphological differences between subsp. microphyllum and subsp. italicum have arisen independently in different locations from a common wider gene pool. Our analyses of AFLP, cpDNA sequences and morphological characters show that there is geographic structure to the genetic variation within H. italicum, with eastern and western Mediterranean groups, which do not correspond with the division into subsp. microphyllum and subsp. italicum as currently circumscribed. Local selection on quantitative trait loci provides sufficient explanation for the morphological divergence observed and is consistent with genetic data. Within the western Mediterranean group of the species we found considerable polymorphism in chloroplast DNA sequences among and within some populations. Comparison with chloroplast DNA sequences from other Helichrysum species showed that some chloroplast haplotypes are shared across species.  相似文献   

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Lunaria annua is overviewed and its two subspecies, subsp. annua and subsp. pachyrrhiza, discussed, the latter described. Two cultivars of subsp. pachyrrhiza, ‘Corfu Blue’ and ‘Mistras’ are illustrated and described. Details of cultivation are also included.  相似文献   

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