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1.
Zygophyllum fabago L. (Zygophyllaceae) can be found in the Middle East, in North Africa and in the arid zones of the Mediterranean region. It easily establishes itself in new regions, and is considered an invasive plant. They undergo ambophilous pollination, as there is a relationship between this type of pollination and its allergenic incidence. A combination of transmission electron microscopy with immunocytochemical methods was used to localize allergenic proteins during hydration and activation processes. Germination was induced in vitro for 1,2,4,6, and 30 min. The activated proteins reacting with antibodies present in human sera from allergenic patients are found in the cytoplasm, intine, exine and exudates from the pollen grains. The activation time plays an important role on the labelling intensity. Labelling of allergenic proteins was abundant at 1 and 2 min of activation, and decreased at 4 and 6 min. The rapid activation and release of the allergenic proteins appears to be the main cause of allergenic activity of Z. fabago pollen grains.  相似文献   

2.
Zygophyllum species are succulent plants that are drought resistant and/or salt tolerant, growing under severe, dry climatic conditions. Despite their importance and abundance in the Mediterranean and Middle East regions, there is little information concerning molecular variations among species of this genus. Genetic diversity was assessed, using RAPD primers, of 12 populations of Z. coccineum, Z. album and Z. aegyptium collected from various locations in Egypt and Saudi Arabia. Yong leaves were used for DNA extraction. Genetic distances were calculated using Nei's method. A dendrogram was constructed based on the similarity data matrix by unweighted pair group method using arithmetic averages cluster analysis. Analysis with RAPD markers revealed genetic variation between and within populations of Zygophyllum. Zygophyllum coccineum showed higher levels of genetic variation and more unique alleles than the other species.  相似文献   

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The Asian interior arid zone is the largest desert landform system in the Northern Hemisphere, and has high biodiversity. Little is currently known about the evolutionary history of its biota. In this study, we used Zygophyllum, an important and characteristic component of the Asian interior arid zone, to provide new insights into the evolution of this biota. By greatly enlarged taxon sampling, we present the phylogenetic analysis of Asian Zygophyllum based on two plastid and one nuclear markers. Our phylogenetic analyses indicate that Asian Zygophyllum and Sarcozygium form a clade and Sarcozygium is further embedded within the shrub subclade. An integration of phylogenetic, biogeographic, and molecular dating methods indicates that Zygophyllum successfully colonized the Asian interior from Africa in the early Oligocene, and Asian Zygophyllum became differentiated in the early Miocene and underwent a burst of diversification in the late Miocene associated with the expansion of Asian interior arid lands due to orogenetic and climatic changes. Combining diversification patterns of other important components of the Asian interior arid zone, we propose a multi-stage evolution model for this biota: the late Eocene–early Oligocene origin, the early Miocene expansion, and the middle-late Miocene rapid expansion to the whole Asian interior arid zone. This study also demonstrates that, for Zygophyllum and perhaps other arid-adapted organisms, arid biomes are evolutionary cradles of diversity.  相似文献   

5.
Introduction – The aerial parts of Zygophyllum album L. are used in folk medicine as an antidiabetic agent and as a drug active against several pathologies. In this work we present the chemical composition of Algerian essential oils obtained by microwave accelerated distillation (MAD) extraction, a solventless method assisted by microwave. Objective – Under the same analytical conditions and using GC‐FID and GC‐MS, the chemical composition of the essential oil of Zygophyllum album L. extracted by MAD was compared with that achieved using hydrodistillation (HD). Methodology – The extracted compounds were hydrosoluble, and they were removed from the aqueous solution by a liquid extraction with an organic solvent. Results – Employing MAD (100°C, 30 min), the essential oil contained mainly oxygenated monoterpenes with major constituents: carvone and α‐terpineol. However, most of the compounds present in the hydrodistilled volatile fraction were not terpene species, with β‐damascenone as a major constituent. Conclusion – The MAD method appears to be more efficient than HD: after 30 min extraction time, the obtained yields (i.e. 0.002%) were comparable to those provided by HD after 3 h extraction. MAD seems to be more convenient since the volatile fraction is richer in oxygenated monoterpenes, species that are recognised for their olfactory value and their contribution to the fragrance of the essential oil. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

6.
The enhanced understanding of chloroplast genomics would facilitate various biotechnology applications; however, the chloroplast (cp) genome / plastome characteristics of plants like Fagonia indica Burm.f. (family Zygophyllaceae), which have the capability to grow in extremely hot sand desert, have been rarely understood. The de novo genome sequence of F. indica using the Illumina high-throughput sequencing technology determined 128,379 bp long cp genome, encode 115 unique coding genes. The present study added the evidence of the loss of a copy of the IR in the cp genome of the taxa capable to grow in the hot sand desert. The maximum likelihood analysis revealed two distinct sub-clades i.e. Krameriaceae and Zygophyllaceae of the order Zygophyllales, nested within fabids.  相似文献   

7.
The plastid coding rbcL and non-coding trnLF regions of 53 of 55 southern African Zygophyllum species were sequenced and used to evaluate the phylogenetic relationships within the southern African representatives of the genus. Published sequences of the same gene regions of Australian, Asian and North African Zygophyllum species were included to assess the relationships of the species from these regions to the southern African species. The addition of Z. stapffii from Namibia, found to be conspecific with Z. orbiculatum from Angola, lead to a greatly resolved tree. The molecular results were largely congruent with a recent sectional classification of the southern African species and supported their subdivision into subgenera Agrophyllum and Zygophyllum. Reconstruction of the character evolution of capsule dehiscence, seed attachment and seed mucilage showed that these characters allowed a division of southern African species into the two subgenera but that this could not be applied to species occurring elsewhere. Other morphological characters were found to vary and unique character combinations, rather than unique characters, were found to be of systematic value in sectional delimitation. The study suggests that repeated radiations from the horn of Africa to southern Africa and Asia and back lead to the present distribution of the taxa in the subfamily Zygophylloideae. Although this study supports some of the recent taxonomic changes in the group, the unresolved relationships between the proposed genera Tetraena and Roepera and those retained as Zygophyllum species suggest that changes to the taxonomy may have been premature.  相似文献   

8.
藜叶中黄酮类化合物体外抗氧化活性研究   总被引:5,自引:0,他引:5  
为了探讨藜叶中黄酮类化合物的体外抗氧化活性,采用有机溶剂提取法和色谱柱法对藜叶中化学成分进行提取与分离;以Vc作对照,对分离纯化的芦丁、乙酸乙酯浸膏和正丁醇浸膏进行DPPH·、O2^-·和·OH的清除效果试验。结果表明:三者对DPPH·、O2^-·、·OH均具有清除作用,且与浓度呈量效关系,芦丁对·OH清除效果优于Vc,芦丁具有较强的清除DPPH·能力,其IC50为0.05μg/mL。  相似文献   

9.
Anatomy of the endophyte of Viscum album L. (Loranthaceae). An anatomical investigation into the nature of the host-parasite interaction of V. album and several of its phanerogamic hosts using SEM and light microscopy was conducted. Three kinds of parasite cell (haustorial parenchyma cells, cells resembling transfer cells and haustorial tracheids) were identified at the host-parasite interface. The terms haustorial parenchyma and haustorial tracheid are defined. Haustorial tracheids were seen to have penetrated the walls of host vessel elements and it is suggested that V. album is able to establish on a wide range of hosts because of the anatomically plastic nature of its haustorium. The development of the haustorium depends to a large extent on the nature of the surrounding host tissues. Parasite-induced host abnormalities including hypertrophy, distorted xylem elements, vessel-wall penetration and tylosis-occluded vessels were observed. The macroanatomical features observed are discussed and interpreted by-proposing a new theory for the ontogenesis of the V. album haustorium. Cortical strands with 'chisel' and 'pencil' shaped apices were both found to be present at the same time on one plant and thus were not seasonally separated.  相似文献   

10.
The glandular trichomes ofFagoniaconsist of one secretory celland a multicellular stalk, which develops by division, elongationand elevation of epidermal cells. The latter become seperatedfrom the mesophyll and a subepidermal chamber is formed. Thelength of the stalk, which differs in the various species orvarieties is determined by the number of cell divisions and/or the extent of cell elongation. Although the basic morphologyand development of the trichomes of the species and varietiesexamined are similar, two types of mature trichomes can be distinguished:one occurs in the two examined varieties ofF. mollisand thesecond inF. glutinosaandF. arabica. The secretory cells of thesecond type possess a very thick wall and bear a porous cupuleon their top. Histochemical tests revealed that the sticky substancesecreted by the secretory cells contains mainly polysaccharidesand lipophilic compounds. The secreted material exhibits autofluorescence.InF. mollisvar.hispidachanges in the amount and shape of thefluorescent material inside the secretory cell, during the courseof development, have been observed. The contribution of theglandular trichomes inFagoniaspecies to survival in hot desertconditions is discussed. Fagonia; glandular trichomes; subepidermal chamber; secreted material; adaptation to desert conditions; stalk; fluorescence  相似文献   

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12.
在光学显微镜和扫描电子显微镜下观察了蒺藜科四合木属四合木(Tetraena mongolica Maim.)木材结构.其导管分子直径小,管壁厚,分布密度高,分子短,端壁几乎水平,具单穿孔;管间纹孔为对列或互列的具缘纹孔;韧性纤维短、壁厚、壁上有较少的单纹孔;同型单列射线、分布密度高;轴向薄壁组织散生或傍导管生.这些表明四合木的木材解剖特征是与干旱环境条件是相适应的.  相似文献   

13.
Summary.  The wild form of the commonly cultivated Rosa chinensis Jacq., f. spontanea Rehder & Wilson, is illustrated and described. The history of its discovery and introduction to cultivation in western gardens is given. The typification and synonymy of R. chinensis are discussed.  相似文献   

14.
Abstract

Viscum album L. ssp. album is semi-parasitic on deciduous trees and shrubs. In order to identify hosts and map the distribution of V. album ssp. album in Croatia and Slovenia, field research was carried out, and herbaria were surveyed. In Croatia and Slovenia, V. album ssp. album occurred on 59 taxa. In Croatia, there were 52 hosts (33 autochthonous and 15 allochthonous species, two cultivars and two hybrids). In Slovenia, there were 25 hosts (21 autochthonous and four allochthonous species). There were 18 hosts common to both countries, 34 hosts were found only in Croatia, and seven hosts only in Slovenia. The hosts belonged to 13 families. The majority of these (19 species) belong to the Rosaceae, followed by Salicaceae, Aceraceae, Betulaceae, Fagaceae, Juglandaceae, Tiliaceae, Hippocastanaceae, Ulmaceae, Oleaceae, Fabaceae, Moraceae and Viscaceae. All hosts have been previously recorded in the literature, except Alnus japonica (Thunb.) Steud., Amelanchier lamarckii F.G. Schroed. and Crataegus nigra Waldst. et Kit. The distribution of this mistletoe was scattered, due to the scattered distribution of hosts, local conditions, movement of bird-vectors, etc. A continuous distribution was found only in part of the distribution area of narrow-leaved ash (Fraxinus angustifolia Vahl).  相似文献   

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The chromosome numbers and meiotic behaviour of twenty morphologically variable populations of 7. terrestris and four of T. alatus were studied and compared. All populations of /. terrestris were hexaploid (2n = 36). They fall in one of the three morphological–eytological groups: I) robust with normal meiosis and pollen grains, II) less–robust with abnormal meiosis and high frequency of smaller pollen grains, and III) mixture of type II and dwarf plants. Seed set was high in all but the dwarfs. It appears that group I reproduces sexually while the other two groups have a certain degree of apomixis, and that the dwarf plants probably resulted from the fusion of cytologically unbalanced gametes. Tribulus alatus populations were tetraploid (2n = 24). Bud material adequate for meiotic studies were unavailable, but the wide range in size of pollen grains indirectly signifies meiotic abnormalities. So far, only the tetraploid race has been examined, while other chromosome races may exist.  相似文献   

17.
Barley‐pathogenic Pyrenophora isolates are P. graminea (PG), P. teres f. maculata (PTM) and P. teres f. teres (PTT), which cause foliar leaf stripe, spot blotch and net blotch lesions, respectively. However, the species are often indistinguishable by morphological and cultural characteristics. Random amplified polymorphic DNA (RAPD) analysis has been used to study the genetic relationship amongst 11 PG, 9 PTM and 23 PTT isolates from distant geographical locations. Using seven primers, 55 (52.38%) polymorphic DNA bands were detected out of 105 different fragments amplified in the three pathogens. Genotypic diversity was high as all but two PTT strains had distinct multilocus RAPD fingerprints. Unweighted pair‐group method with arithmetic average (UPGMA) clustering separated the isolates into three main clusters, corresponding to the three pathogens studied. No clear geographical substructuring was found. Nei's gene diversity analysis detected only small differences (max. 6.6%) in band frequencies but considerable levels of differentiation were observed among the pathogen species/forms. However, the variability among the Pyrenophora species/forms (max. 42.0%) was less than within species/forms (max. 58%). Nei's unbiased genetic distance values were in agreement with UPGMA clustering and gene diversity analysis: the two forms of P. teres showed higher divergence from one another (D = 0.132) than the distance found between PG and PTM (D = 0.094). The results suggest that the present taxonomical classification of these morphological taxa may not correspond to their phylogenetic relationship and that there is a very close genetic relationship amongst barley‐pathogenic Pyrenophora species, but genetic exchanges between them could be infrequent.  相似文献   

18.
We report the development of nine microsatellite markers in globe artichoke (Cynara cardunculus L. var. scolymus). Four markers were obtained from sequences available in GenBank and five were isolated using a biotin/streptavidin capture technique for (CA)n and (CT)n motifs directly from artichoke genomic DNA. Polymorphism was explored in 15 artichoke accessions that represent the genetic variation within cultivated varietal types. Inter‐specific amplification was tested using cultivated cardoon (C. cardunculus L. var. altilis DC.) and wild cardoon (C. cardunculus L. var. sylvestris Lam.). Primers and conditions for polymerase chain reaction (PCR) amplification of detected loci are described.  相似文献   

19.
Zuber D  Widmer A 《Molecular ecology》2000,9(8):1069-1073
Nuclear ribosomal DNA (nrDNA) ITS sequences and partial sequences of three non-coding chloroplast DNA (cpDNA) introns and spacers were used to assess genetic variation within and among three presumed host races of the hemi-parasite Viscum album L. Currently, identification of host races occurs via the host trees, and morphological differences are minute at best. cpDNA and nrDNA ITS sequences revealed little sequence variation, but the variation found consistently supported the distinction of three host races. cpDNA and ITS sequences were not incongruent, as assessed by the incongruence length difference test. A combined analysis supported the sister group relationship between mistletoes from deciduous trees and fir.  相似文献   

20.
Here, we first report hyperparasitism of Honey Suckeled Mistletoe, Dendrophthoe falcata var. falcata (Loranthaceae) by Pseudaulacaspis cockerelli (Diaspididae). The infected mistletoe was found parasitising branches of the Senna siamea host. Pear-shaped white spots were observed on abaxial and adaxial leaf surfaces, stem and few on the haustorial surfaces of the mistletoe. Close inspection revealed a yellowish-brown spot on individual white spots. These were identified on the basis of morphological features as Cockerell Scales hidden in the white-spot like self-secreted waxy armours. No incidence of such an infection was seen on any part of the mistletoe host, Senna siamea.  相似文献   

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