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1.
The taxonomy of the desert shrub genus Fagonia is revised in detail. In total 167 names are accounted for, lectotypes are selected for 33 names, and two names are neotypified. A key to the 34 species is presented, as well as distribution maps for each species. Three new species are described and illustrated, F. densispina and F. latistipulata from Somalia, and F. hadramautica from Yemen. Of the accepted species, 24 are restricted to the Old World and eight to the New World. Most of the Old World species are confined to the Saharo‐Sindian region, with two extending to parts of Macaronesia. Eight species are endemic to the Somali‐Masai region, and two are restricted to southern Africa. In the New World four species are endemic to Baja California, two to northern Baja California and adjacent parts of southwestern USA, one to the province of Coahuila in northeastern Mexico, and one to Chile and Peru. The names of all four species of Fagonia currently on the IUCN Red List of Threatened Plants are put into synonymy.  相似文献   

2.
As part of our search of new bioactive compounds from indigenous medicinal plants, phytochemical investigation of the aerial parts of Fagonia indica Burm led to the isolation of seven compounds including two new compounds, namely, indicacin (1) and fagonicin (2), and five known compounds (37) from the methanol extract. Compounds 6 and 7 are hitherto unreported from this plant. The structures of the new compounds were elucidated from their spectral data, mainly HREIMS, 1D NMR (1H, 13C NMR, and DEPT) and 2D NMR (COSY, NOESY, HSQC and HMBC), and by comparison with the literature data. The new compounds 1 and 2 were assayed for their cytotoxicity against human colorectal cancer cell line H-29. Compound 1 exhibited 51.40% cytotoxicity at 6.25 μM/mL dose whereas compound 2 demonstrated 39.3% cytotoxicity at the same dose.  相似文献   

3.
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   

4.
Guaiacum coulteri is a dry forest hardwood species of conservation concern endemic to the Pacific coast of Mexico. Fifteen microsatellite markers were developed which show high levels of polymorphism across two populations with the number of alleles ranging from four to 21. Most loci additionally exhibited consistent multiple banding patterns, indicating the likely polyploidy of this species. All loci were tested for cross-amplification with most found to amplify well across the genus Guaiacum, although amplification in other related genera of the Zygophyllaceae was limited.  相似文献   

5.
Adenium obesum (Forssk.) Roem. & Schult. belonging to the family Apocynaceae, is remarkable for its horticultural and ornamental values, poisonous nature, and medicinal uses. In order to have understanding of cp genome characterization of highly valued medicinal plant, and the evolutionary and systematic relationships, the complete plastome / chloroplast (cp) genome of A. obesum was sequenced. The assembled cp genome of A. obesum was found to be 154,437 bp, with an overall GC content of 38.1%. A total of 127 unique coding genes were annotated including 96 protein-coding genes, 28 tRNA genes, and 3 rRNA genes. The repeat structures were found to comprise of only mononucleotide repeats. The SSR loci are compososed of only A/T bases. The phylogenetic analysis of cp genomes revealed its proximity with Nerium oleander.  相似文献   

6.
Tylophora indica (Burm.f.) Merr (syn. T. asthmatica), is being indiscriminately collected for medicinal use which is not sustainable. Conservation of the species requires information on existing genetic content and its distribution in different populations. In the present study, polymorphism in allozyme and RAPD profiles of five populations were analysed using six enzyme systems and ten random primers. Genetic content in terms of allozymes and RAPDs as revealed by Shannon-Weiner index was more or less same in all the populations. Evenness as calculated from observed diversity (Shannon-Weiner index, H’) and the maximum expected diversity (Hmax) for the allozymes and RAPDs was high for individual populations indicating that the distribution of genetic content was fairly uniform. From the results, it was concluded that collection of few genotypes from geographically distinct locations rather than intensive collection within one or two locations would be representative of the genetic variability present in this species.  相似文献   

7.
The chloroplasts genome encodes several key proteins that involves in the process of the photosynthesis and also in other metabolic processes important for growth and development, yield, biomass, and plant interactions with their environment. The present study aimed to sequencing of cp genome of Fagonia indica Burm.f (Zygophyllaceae), -a plant that occurs even in the hot desert condition of the inner zone of Rub′ al-Khali (the Empty Quarter) of south-central Arabia, and its comparative analyses with the representative of the sequence of the different categories [viz. (a) with the other member of the family Zygophyllaceae, and with the representatives from: (b) different clade of the angiosperms, (c) flowering plants occurs in different major habitats, (d) different groups of plants, (e) different group of plants having range of biomass, (f) C3 and C4 plants, and (g) the representative from very common, rare and major high yielding crop of the world] to unravel the genetic pattern of similarity and variations. The comparison of F. indica genome in different categories showed strong evidence and further support for the conservative pattern of chloroplast genome, the coding and non-coding region remains conserved even in phylogenetically distant eukaryotic clades, and might not have the sole roles in organism′s yield, rarity or abundance and biomass, and in encountering the stress. Nevertheless, the result could be useful for molecular phylogenetic and molecular ecological and molecular mechanism of photosynthesis.  相似文献   

8.
Panax stipuleanatus (Araliaceae) is an endangered and medicinally important plant endemic to China. However, phylogenetic relationships within the genus Panax have remained unclear. In this study, we sequenced the complete plastome of P. stipuleanatus and included previously reported Panax plastomes to better understand the relationships between species and plastome evolution within the genus Panax. The plastome of P. stipuleanatus is 156,069 base pairs (bp) in length, consisting of a pair of inverted repeats (IRs, each 25,887 bp) that divide the plastome into a large single copy region (LSC, 86,126 bp) and a small single copy region (SSC, 8169 bp). The plastome contains 114 unigenes (80 protein-coding genes, 30 tRNA genes, and 4 rRNA genes). Comparative analyses indicated that the plastome gene content and order, as well as the expansion/contraction of the IR regions, are all highly conserved within Panax. No significant positive selection in the plastid protein-coding genes was observed across the eight Panax species, suggesting the Panax plastomes may have undergone a strong purifying selection. Our phylogenomic analyses resulted in a phylogeny with high resolution and supports for Panax. Nine proteincoding genes and 10 non-coding regions presented high sequence divergence, which could be useful for identifying different Panax species.  相似文献   

9.
Mature leaf explant derived callus of Tylophora indica (Burm. f.) Merrill yielded somatic embryos on MS medium supplied with BA(1-2 mg/L) or kinetin(1-5 mg/L) or kinetin/BA (1-2 mg/L) used along with IAA(0.1-1 mg/L). Maximum somatic embryos (30) could be recovered from 100 mg of embryogenic callus within 60 days at an optimum concentration of 2 mg/L of BA which was also best suited for providing the maximum conversion rate (90%) of embryoids to plantlets. Kinetin (1-5 mg/L), used as the sole growth hormone, induced the development of embryoids showing either shoot or root primordia in 30% of the cultures. However, embryoids with shoot primordia developed roots upon transfer to medium containing IAA(0.1 mg/L) and kinetin(2 mg/L). Embryoids from all cultures germinated in the initiation medium and were transplanted to sterile vermiculite for hardening. After two weeks of hardening, the plantlets were transferred to the green house where they grew and established well showing a high rate of survival (90%).  相似文献   

10.
The mode of chloroplast DNA (cpDNA) inheritance was investigated in the genus Larrea (Zygophyllaceae) by polymerase chain reaction (PCR) amplification of cpDNA fragments using three pairs of chloroplast universal primers. A total of 20 F(1)s from interspecific crosses among five different taxa in the section Bifolium was examined. Twelve F(1)s were from six crosses between L. cuneifolia (4x) and L. divaricata (2x) (Peru or Argentina) or L. tridentata (2x or 4x). Eight F(1)s were from two sets of reciprocal crosses between L. divaricata (2x) (Argentina) and L. tridentata (2x). Length polymorphism was observed in all three regions of cpDNA that separated L. cuneifolia parents from L. divaricata and L. tridentata parents and in one of the three cpDNA regions that differentiated L. divaricata (Argentina) parents from L. tridentata (2x) parents. In each case, it was the paternal cpDNA marker that appeared in the F(1) individuals. This was further confirmed by restriction fragment length polymorphism (RFLP) analysis of the amplified cpDNA fragments. Larrea may be the fifth genus reported in angiosperms with a paternal bias in cpDNA transmission. Possible mechanisms that may result in paternal cpDNA inheritance were briefly reviewed. Based on the observed uniparental paternal inheritance of cpDNA, restriction analysis of the three cpDNA regions and previous cytogenetic studies, L. divaricata was probably the maternal progenitor of L. cuneifolia.  相似文献   

11.
A procedure for rapid in vitro multiplication of Tylophora indica (Burm. f.) Merrill., an important indigenous medicinal plant, has been developed. Addition of ascorbic acid was essential to induce sprouting of axillary buds. Optimum multiplication was observed on MS medium containing 6-benzylamino purine (5.0 mg l–1), -naphathalene-acetic acid (0.5 mg l–1) and ascorbic acid (100 mg l–1). Rooting of in vitro produced shoots was readily achieved with indole-3-acetic acid alone (1.0 mg l–1) in MS. The plantlets thus obtained were successfully transferred to pots in large numbers which grew normally.Abbreviations BAP 6-benzylamino purine - 2,4-D 2,4-dichlorophenoxyacetic acid - GA3 gibberellic acid - IAA indole-3-acetic acid - IBA indole-3-butyric acid - 2ip 2-isopentenyladenine - Kn kinetin - MS Murashige & Skoog media - NAA -naphthalene acetic acid  相似文献   

12.
Seed and trichome morphology of 13 taxa representing the genus Fagonia in Egypt have been studied using light (LM) and scanning electron microscopy (SEM). Macro‐ and micro‐morphological characters, including seed shape, seed size, seed coat sculpture, trichome density and structure were studied to evaluate their systematic significance. Seed shape and trichome density were found to have only minor taxonomic value, but seed coat sculpturing and trichome structure proved to be valuable characters. These characters offer evidence to combine certain species, e.g. Fagonia kassasii and F. schimperi in F. bruguieri, Fagonia microphylla in F. scabra and Fagonia thebaica in F. arabica. However, F. sinaica, F. tristis, F. boveana and F. isotricha should be maintained as separate species. Generally, the different patterns of seed and trichome morphology are useful in delimitation of species within the genus Fagonia, but they could not be used to characterize groups of related species.  相似文献   

13.
Megagametophyte development of Nymphaea nouchali Burm. f. (Nymphaeaceae)   总被引:2,自引:0,他引:2  
The development of reproductive cells has been analysed in Nymphaea nouchali , family Nymphaeaceae, subclass Magnoliidae. Our observations on embryo sac development differ from those in the literature. Megasporogenesis results in a triad of one micropylar cell and two innermost megaspores. Embryo sacs derive from a single functional megaspore and are tetranucleate. Megasporogenesis is monosporic and of the Polygonum type, but mega-gametogenesis is of Oenothera type.  相似文献   

14.
从印度娃儿藤节间外植体获取愈伤组织,分析了糖、赤霉素(GA3)及脱落酸(ABA)对愈伤组织形成体细胞的影响。实验证明,含4μmol/L2,4-二氯苯氧乙酸(2,4-D)的MS培养基是获得具有成胚功能的愈伤组织的最佳培养基。在含有6μmol/L激动素(Kn)的MS培养基上,高达69%的愈伤组织分化为体细胞胚,平均单位外植体(每克愈伤组织)产胚25个。在6μmol/LKn存在的条件下,分析了蔗糖、葡糖糖对胚产生的影响,不同的糖及不同糖浓度对体细胞胚的发生影响很大。6μmol/L Kn与200mmol/L蔗糖处理胚胎发生率最大(71%),单位外植体生成49个胚。然而葡萄糖与Kn、或者葡糖糖、蔗糖与Kn三者加在一起则降低成胚率及产胚数。一定浓度的GA3和ABA能促进体细胞胚的产生。在含200mmol/L蔗糖的培养基中加10μmol/LGA3胚的生成率为98%,单位外植体产胚51个。在含200mmol/L蔗糖的培养基中加2μmol/L ABA能显著增加体细胞胚的量,该培养基上每外植体平均生成44个胚,产率为95%。本研究显示,含200mmol/L蔗糖的培养基中分别加入6μmol/L Kn、10μmol/L GA3或者2μmol/L ABA能显著提高印度娃儿藤体细胞胚发生率,而单独的葡萄糖或葡糖糖和蔗糖则有抑制作用。得到的胚均能正常发育并分化为植株。  相似文献   

15.
Summary A restriction map of the Cucumis melo L. (melon) plastome was constructed by using several mapping approaches: single and double digestions of the chloroplast DNA (chlDNA) with endonucleases (XhoI, SmaI, SacI and PvuII) and hybridization to heterologous chlDNA probes and to isolated melon chlDNA fragments. Four plastome-coded genes were located using heterologous probes. The overall organization and gene position of the melon plastome was found to be similar to that of tobacco and other angiosperm species. Restriction patterns based on digestion of the chlDNA with nine endonucleases were obtained in over 20 wild species and cultivated varieties of Cucumis. These led to mutational analysis of the restiction sites yielding the most parsimonious phylogenetic tree of the Cucumis plastome. Most African species from a compact group (Anguria group) which is distant from the melon, the cucumber and a few other species (C. sagittatus, C. metuliferus and C. humifructus). All of these are also far apart from each other. The distribution of polymorphic restriction sites along the Cucumis plastome is described and conservative regions as well as hot spots are suggested.  相似文献   

16.

Tylophora indica (Burm.f.) Merrill. is a pharmacologically important plant, popular for alkaloidal and non-alkaloidal richness. Large scale propagation of T. indica is difficult in the wild as the seeds are small and the frequency of germination is very poor. In the present study, the genome size estimation of in vitro regenerated (indirect, direct and somatic embryo mediated) T. indica was made by flow cytometric method. Clonal fidelity of the regenerants was assessed using a start codon targeted (SCoT) molecular marker. Initially, the explants were inoculated on Murashige and Skoog basal medium supplemented with various concentrations of plant growth regulators like 2,4-dichlorophenoxy acetic acid (2,4-D), Kinetin, 6-benzyl amino purine (BAP) and 1-naphthalene acetic acid either singly or in combinations. The highest callus induction frequency (87.75%) was obtained in 6.7 µM 2,4-D added MS medium which metamorphosed into progressive stages (globular, heart, torpedo, and cotyledonary) of embryos. Mature and healthy somatic embryos efficiently germinated into plantlets on 8.8 µM BAP?+?1.4 µM GA3 enriched MS medium. Histological and scanning electron microscopic study confirmed the above developing stages. The regenerated shoots were rooted best in 2.45 µM Indole-3-butyric acid supplemented solid MS medium. The plants were hardened and acclimatized with 90% survivability. The flow cytometric 2C DNA content of indirect, direct and somatic embryo derived plants was 1.896 pg, 1.940 pg and 1.926 pg respectively, very similar to the mother plant (1.928 pg). SCoT marker generated a high percentage of monomorphic bands (94%) revealing similarity with the mother plant, thus ensuring genetic fidelity. To the best of our knowledge, this is perhaps the first ever report of 2C DNA content estimation and SCoT marker based genetic homogeneity study in T. indica.

  相似文献   

17.
Summary Alloplasmic compatibility, namely the functional interaction between the nuclear genome of a given species with plastomes and chondriomes of alien species, is of considerable relevance in plant biology. The genus Solanum encompasses a wide spectrum of species and is therefore suitable for a study of this compatibility. We thus chose the nuclear genome of Solanum tuberosum (potato) and organelles (chloroplast and mitochondria) from 14 other Solanum species to initiate an investigation of intrageneric nucleus/organelle interactions. An assessment of the diversity of the chloroplast DNAs from these 15 species resulted in the construction of a plastome dendrogram (phylogenetic tree). In parallel we extended a previous study and performed ten additional fusion combinations by the donor-recipient protoplast fusion procedure, using potato protoplasts as recipients and protoplasts from any of ten other Solanum species as donors. We found that two fusion combinations did not yield cybrids and that the chloroplasts of S. polyadenium and the mitochondria (or mitochondrial components) from S. tarijense could not be transferred to cybrids bearing potato nuclei. In general, there is a correlation, albeit not perfect, between the cybridization data and the plastome dendrogram. These results furnish valuable information toward future transfer of plasmoneencoded breeding traits from wild Solanum species into potato. This information should also be useful for the planning of asymmetric protoplast fusion between potato and wild accessions for the improvement of pathogen and stress resistance of potato cultivars.  相似文献   

18.
Merremia vitifolia (Burm.f.) Hallier f., an ethnomedicinally important plant, used in the tribal areas to treat various ailments including fever, headache, eye inflammation, rheumatism, dysentery, jaundice and urinary diseases. The present study explored the biological efficacy of the aqueous fraction of M. vitifolia leaves (AFMV) through in vitro and in vivo experimental models. The thrombolytic and anti-arthritic effects of AFMV were evaluated by using the clot lysis technique and inhibition of protein denaturation technique, respectively. The anti-nociceptive activity of AFMV was investigated in Swiss Albino mice by acetic acid-induced writhing test and formalin-induced paw licking test. The antioxidant activities of AFMV, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and total reducing power, were also tested. The qualitative phytochemical assays exhibited AFMV contains secondary metabolites such as alkaloid, carbohydrate, flavonoid, tannin, triterpenoids and phenols. In addition, AFMV showed strong antioxidant effects with the highest scavenging activity (IC50 146.61 µg/mL) and reducing power was increased with a dose-dependent manner. AFMV also revealed notable clot lysis effect and substantial anti-arthritic activity at higher doses (500 µg/mL) as compared with the control. The results demonstrated a promising reduction of the number of writhing and duration of paw licking in acetic acid-induced writhing test and formalin-induced paw licking test in a dose-dependent manner, respectively. In conclusion, AFMV provides the scientific basis of its folkloric usage, suggesting it as the vital source of dietary supplement.  相似文献   

19.
Tijet N  Helvig C  Feyereisen R 《Gene》2001,262(1-2):189-198
The cytochrome P450 gene superfamily is represented by 90 sequences in the Drosophila melanogaster genome. Of these 90 P450 sequences, 83 code for apparently functional genes whereas seven are apparent pseudogenes. More than half of the genes belong to only two families, CYP4 and CYP6. The CYP6 family is insect specific whereas the CYP4 family includes sequences from vertebrates. There are eight genes coding for mitochondrial P450s as deduced from their homology to CYP12A1 from the house fly. The genetic map of the distribution of D. melanogaster P450 genes shows (a) the absence of P450 genes on the chromosome 4 and Y, (b) more than half of the P450 genes are found on chromosome 2, and (c) the largest cluster contains nine genes. Sequence alignments were used to draw phylogenetic trees and to analyze the intron-exon organization of each functional P450 gene. Only five P450 genes are intronless. We found 57 unique intron positions, of which 23 were phase zero, 19 were phase one and 15 were phase two. There was a relatively good correlation between intron conservation and phylogenetic relationship between members of the P450 subfamilies. Although the function of many P450 proteins from vertebrates, fungi, plants and bacteria is known, only a single P450 from D. melanogaster, CYP6A2, has been functionally characterized. Gene organization appears to be a useful tool in the study of the regulation, the physiological role and the function of these P450s.  相似文献   

20.
Two stick-like acridids (Orthoptera: Proscopiidae) from Argentina, Anchocoema bidentata Mello-Leitao and Astroma saltense Mello-Leitao, were evaluated as potential biological control agents of creosote bush (Larrea tridentata (DC.) Coville) in the southwestern United States. Their biology, behavior and geographic distribution of those species were studied. The host plant ranges for both insects were established through nymph feeding preference and development tests in the laboratory and in the field. A total of 33 species of plants belonging to 13 families were tested. Anchocoema bidentata and A. saltense are mimetic species, having as many as three generations a year, and exhibit strong sexual dimorphism; females are larger and less mobile than males. In both species, females laid egg masses in the soil. First instars appeared in the field at the end of the spring, the second generation at mid-summer, and a third at the end of the summer. Adults of A. bidentata and A. saltense appeared in the field at the beginning of the spring. The laboratory multiple-choice feeding test showed that A. bidentata preferred Larrea divaricata Cav., whereas A. saltense preferred L. divaricata and L. cuneifolia Cav. In the nymph development test (no choice), A. bidentata was able to complete its development only on L. divaricata and L. cuneifolia, while Astroma saltense completed its development on six plant species: L divaricata, L. cuneifolia, Bulnesia retama (Gillies ex Hooker et Arnott), B. schickendantzi Hieron (all Zygophyllaceae), Zuccagnia punctata Cav., and Prosopis torquata (Cav. Ap. Lag.) (both Fabaseae). We concluded that A. bidentata could be a biocontrol agent for L. tridentata because the first instar can complete its development only on Larrea spp. Regarding A. saltense, this species showed a wide host range and should not be considered as a biological control agent of L. tridentata.  相似文献   

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