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In the present study, the chemical composition of the essential oils from aerial parts of Centaurea grinensis Reuter (K) collected at ?uta Lova, near Senj (Croatia), and aerial parts (L1) and flowers (L2) of C. apiculata Ledeb. collected near Rebro village, near Breznik town, Znepole Region (Bulgaria), both belonging to subgenus Lopholoma (Cass.) Dobrocz, was evaluated by GC and GC-MS. The main components of K were 4-vinyl guaiacol (21.5%), hexadecanoic acid (16.2%), acetophenone (12.5%). Caryophyllene oxide (15.8%) together with sphathulenol (14.5%) and humulene epoxide II (9.4%) were recognized as the main constituent of both the aerial part (L1) and flowers (L2) of C. apiculata. Furthermore, a complete review on the composition of the essential oils of all the Centaurea taxa belonging to subgenus Lopholoma studied so far has been inserted and cluster analysis (PCA) was carried out.  相似文献   

3.
Giant bear-dogs of the genera Amphicyon and Ischyrocyon (Carnivora, Amphicyonidae, Amphicyoninae) were the largest carnivorans in North America during middle and late Miocene (17.5–8.8 Mya) with a dental and skeletal morphology that combined features found in living Ursidae, Canidae, and Felidae. This study tests previously proposed models of diet and hunting behaviour of these extinct carnivorans. Relative grinding area (RGA) of lower molars and wear pattern on upper molars suggest that bear-dogs were carnivorous. Amphicyon and Ischyrocyon possessed skeletal features of both ambush (short distal limb segments) and pursuit (caudally bent olecranon process of ulna) living predators. Therefore, bear-dogs probably pursued their prey (mediportal ungulates) for a longer distance but at a slower speed than do living ambush predators. Upon catching up to its prey a bear-dog probably seized it with powerfully muscled forelimbs and killed it by tearing into its ribcage or neck with canines set in a narrow rostrum.  相似文献   

4.
Abstract

The terrestrial orchid, Orchis pauciflora Ten., growing in poor grassland and garrigue of Central Mediterranean region, is local and rare and has been included in the red lists of several Italian regions. We investigated the diversity of fungal associates in O. pauciflora adult plants collected in two protected areas of Tuscany (Central Italy). Genomic DNA was extracted from mycorrhizal roots of 12 orchid plants and the fungal ITS were amplified and sequenced. Several fungal associates, belonging to different taxa of basidiomycetes (Tulasnellaceae) and ascomycetes such as Leptodontidium, Exophiala and Phialophora species, were recovered. The trophic role of these fungi and their impact on O. pauciflora growth and conservation are discussed.  相似文献   

5.
Total extracts and kuwanon G from Morus nigra root bark showed antifungal activity against several phytopathogenic fungi, with minimal inhibitory concentration (MIC50) ranging from 32 to 128 μg/ml and from 16 to 64 μg/ml, respectively. Acetonic extracts inhibited 60% B. cinerea biofilm formation at concentration of 128 μg/ml.  相似文献   

6.
Abstract

The large amount of morphological variability within Fritillaria montana Hoppe ex W.D.J. Koch, a southeastern European species described from northeastern Italy, led to the creation of several further taxa: Fritillaria caussolensis Goaty & Pons ex Adoino from southeastern France, Fritillaria orsiniana Parl. from central Italy, Fritillaria intermedia N. Terracc. and Fritillaria pollinensis N. Terracc. from southern Italy. Aiming to test the taxonomic value of these taxa, a biometric study of both herbarium and living specimens of F. montana s.l. is carried out. A total of 22 morphological features were analysed and measured in 417 plants from 46 different localities, including loci classici of all the involved taxa. In addition, typical populations of F. montana, F. caussolensis, F. intermedia, F. orsiniana and F. pollinensis and also several other Italian populations resulted with 2n = 18 chromosomes. We also counted 2n = 27 chromosomes in endotriploid cells of plants from Abruzzo. However, there is no clear‐cut correlation between morphology and karyology. The biometric analysis, together with many observations on fresh material in the field, revealed that F. montana is a single polymorphic species with no infraspecific taxa.  相似文献   

7.
The present work is aimed at studying several Asperula (Rubiaceae) sect. Cynanchicae populations in southern Apennines, Italy, with particular reference to those referred to A. calabra, by employing biometrical methods on macromorphological data. Among other historical misapplications, A. cynanchica subsp. cynanchica seems to be very rare or missing in southern Italy. The enigmatic Asperula calabra, confirmed to be limited to a single mountain population in Calabria, appears to be strictly related to A. aristata subsp. scabra, so we suggest to treat it as a further subspecies of A. aristata. This latter species is otherwise distributed throughout southern Italy with subsp. scabra and subsp. aristata, characterised by slight morphological differences, which are correlated to altitudinal ranges.  相似文献   

8.
Impatiens L. is taxonomically a complicated genus that necessitates fresh characterization to resolve its taxonomy. This study therefore aimed at ascertaining micro-morphological characters in the foliar epidermis of Impatiens. For this purpose, we gathered twelve taxa (10 species and 2 subspecies) mostly from the northern regions of Pakistan and studied qualitative and quantitative characters depicting variation in epidermal cells, stomata, and trichomes on both surfaces. Multicellular, uniseriate trichomes were observed only in I. balsamina L., and raphides in I. balfourii Hook. f. and I. thomsonii Hook. f. while stomata were exclusively anomocytic in all species. Morphological variation in the foliar epidermal characters and their diagnostic value has been depicted by constructing a taxonomic key to all taxa. The study revealed that although foliar epidermal characters in Impatiens did not desirably assort taxa on the basis of structural topographies, yet demonstrated adequate variation distinguishing the Pakistani taxa.  相似文献   

9.
Abstract

A two-year study has been conducted in an abandoned Pb/Zn mining site, with the aim of investigating the feasibility of phytoremediation using two native Mediterranean plants (Pistacia lentiscus and Scrophularia bicolor) and of assessing the performance of amendments able to reduce the toxic effects of heavy metals. The amendments used were compost, chemical fertilizer, and zeolites, used singly or in combination. Depending on the amendments applied, the two species showed different mortality rates in the different plots, but all produced an increase in P. lentiscus survival, while S. bicolor survival improved only when amended with zeolite or zeolite + fertilizer. Scrophularia bicolor proved to be a more efficient accumulator than P. lentiscus, especially for Pb uptake. Pistacia lentiscus accumulated metals mostly in the roots. The effect of amendments was to generally reduce the bioavailable metal fraction, especially lead, in the plots amended with compost. Pistacia lentiscus proved to be the most suitable species for phytostabilization and environmental restoration, both for its resistance to metals and high phytomass production. The experiments demonstrate that the use of compost not only encourages this kind of revegetation in degraded areas, but is also an economical option that uses a by-product of solid municipal waste treatment.  相似文献   

10.
Abstract

To analyze biomass and nutrient dynamics of Mediterranean seasonal dimorphic shrubs, aboveground biomass (AGB) and belowground biomass (BGB), litterfall (LF), aboveground net annual primary production (ANPP), and nutrient allocation and turnover were estimated in Cistus salviifolius and C. ladanifer, during two years, in southern Portugal. AGB, BGB, LF, and ANPP of C. salviifolius are within the range reported for other seasonal dimorphic plants, while those of C. ladanifer are closer to evergreen sclerophylls. Leaf renewal was higher for C. salviifolius than for C. ladanifer, especially for winter leaves, while root-to-shoot ratio and accumulation of live wood was greater in the latter. The concentrations of N, K, Ca, and Mg were lower in leaves of C. ladanifer than in those of C. salviifolius, suggesting less nutritive requirements for the former. Moreover, leaf nutrient translocation was higher in C. ladanifer than in C. salviifolius. Therefore, C. ladanifer shrubs seem to be more efficient with respect to carbon uptake, even during severe drought, while those of C. salviifolius act as weaker sinks more susceptible to the negative effects of drought. Additionally, C. ladanifer seems to have a competitive advantage in more arid conditions, as a great proportion of its annual nutrient requirement may derive from internal sources.  相似文献   

11.
Abstract

Semi-natural dry grasslands are habitats of high conservation concern. These ecosystems have not been extensively explored in the Tyrrhenian sector of the Italian peninsula, particularly in the Submediterranean climatic region. In order to address this issue and to define the synecology, syndynamics and syntaxonomy of calcareous grasslands in this area, we considered 127 phytosociological relevés. Our sampling was performed in the Lazio region according to a stratified sampling scheme based on homogeneous land units, defined by means of an ecological land classification process. We analyzed the vegetation data using multivariate methods. Two new associations, whose typical aspects occur in the mesotemperate phytoclimatic belt, were identified:Erysimo pseudorhaetici-Dasypyretum villosi (Taenianthero-Aegilopion) and Scorpiuro muricati-Brometum erecti (Phleo-Bromion). Phytoclimatic belts within the Submediterranean region cause a significant degree of differentiation within Scorpiuro-Brometum, which was described at the subassociation and variant levels. The overall relevance of therophytes represents the most important feature distinguishing Scorpiuro-Brometum from the published Bromus erectus associations. At a finer scale, the presence of the two physiognomically different grassland communities is related to different soil types. All these communities are dynamically linked to Quercus virgiliana and Q. pubescens woods, and contribute to the coenological differentiation of the vegetation series related to such woodlands.  相似文献   

12.
Constraining the origin of animal groups is allowed, to some extent, by discoveries of Cambrian Lagerstätten that preserve both mineralizing and nonmineralizing organisms. A new species is reported here of the Cambrian arthropod Skania, which bears an exoskeleton that shares homologies with the Neoproterozoic (Ediacaran) organism Parvancorina and firmly establishes a Precambrian root for arthropods. A new monophyletic group, Parvancorinomorpha, is proposed as the first clade within the arthropod crown group demonstrably ranging across the Neoproterozoic–Paleozoic transition. The Parvancorinomorpha is interpreted to be the sister group of the Arachnomorpha. Incipient cephalization in Skania and related genera represents a step in the progression toward division of a cephalon from a large posterior trunk as shown in Cambrian arachnomorphs such as naraoiids and the addition of a pygidium and thoracic tergites as shown in the arachnomorph clade basal to trilobites. This evidence can serve as a new calibration point for estimating the divergence time for the last common ancestor of arthropods and priapulids based on molecular clock methods.  相似文献   

13.
Ragweed allergy is one of the primary causes of seasonal allergies in Europe and its prevalence is expected to rise. The leaf beetle Ophraella communa, recently and accidentally established in N-Italy and S-Switzerland, represents a promising approach to control ragweed, but negative side effects should be excluded before its use. Since biotic and abiotic stresses are known to influence the allergenicity of pollen, we set out to assess the effect of sub-lethal defoliation by O. communa on the quantity and quality of ragweed pollen. Seventeen sister pairs (including six clones) of ragweed plants were grown in controlled conditions. One of each pair was exposed to O. communa as soon as the plant started to produce reproductive structures. After 10 weeks of exposure, plant traits were measured as a proxy for pollen quantity. Pollen quality was assessed by measuring its viability and allergenicity. Generally, plants produced very few male flowers and little amount of pollen. Damage by the beetle was severe with most of the leaf tissue removed, but no treatment effect was found on any of the quantitative and qualitative traits assessed. In conclusion, O. communa did not increase the amount or allergenicity of ragweed pollen grains in our experimental conditions.  相似文献   

14.
E. Gatti  M. Vecchi 《Plant biosystems》2017,151(4):581-583
An original protocol of micropropagation of Aristolochia rotunda L., an important herb for the survival of an endangered butterfly was developed. The cytokinin 6-benzylaminopurine affected the production of new shoots but had no effect on shoot length. The addition of indole-3-butyric acid (IBA) had a negative effect on shoot length. Best results in terms of rooting percentage and root length were achieved with 1.5 μM IBA. The protocol can be employed to enhance the number of A. rotunda in the environment.  相似文献   

15.
A new Centaurea L. (Asteraceae) species from Turkey is described and illustrated. Centaurea mersinensis Uysal and Hamzao?lu exists on calcareous slopes in Pinus brutia forests of Ayd?nc?k (Mersin) in southern Anatolia. It belongs to C. sect. Phalolepis (Cass.) DC., and taxonomically its closest relative is C. lycaonica. Diagnostic morphological characters from very similar taxa are provided, and a key is provided that includes related species of sect. Phalolepis from Turkey. The geographical distribution of the new species and relatives of the same section are mapped. The chromosome number of C. mersinensis, 2n = 18, counted in root tips, is also reported and illustrated.  相似文献   

16.
Abstract

Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.  相似文献   

17.
Argania spinosa (L.) Skeels is an endemic Moroccan species belonging to Sapotaceae family. In this work, lipophilic and aqueous extracts were obtained from leaves and subjected to a chemical profiling by MS and LC-MS/MS. Pentacyclic terpenoids were identified and quantified in the lipophilic fraction, while phenolic compounds (mainly belonging to flavonols and flavan-3-ols) were identified in the aqueous fraction. The antibacterial activities of fractions were evaluated in vitro against both reference Gram-positive and -negative bacterial strains and clinical isolates of methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA and MRSA); in addition, the compounds quantified as main components in each extract were assayed against reference strains. A relevant antibacterial activity was observed against reference MSSA and MRSA strains of S. aureus: for the lipophilic fraction, MIC50 values obtained were 177.8 and 170.6 μg/mL for the former and the latter, respectively, while for the aqueous fraction were 215.5 and 233.3 μg/mL. These inhibitory activities could be mainly ascribed to ursolic and oleanolic acids, among pentacyclic terpenoids, and to quercetin concerning phenolic compounds. A remarkable antibacterial activity was also observed against clinical isolates, thus argan leaves can be considered of interest in the chemotherapy of human infections.  相似文献   

18.
Abstract

The production of carotenoids from Blakeslea trispora cells in a synthetic medium has been reported, with the main products being β-carotene, lycopene, and γ-carotene. The effect of biomass pretreatment and solvent extraction on their selective recovery is reported here. Eight solvents of class II and III of the International Conference of Harmonization: ethanol, methanol, acetone, 2-propanol, pentane, hexane, ethyl acetate, and ethyl ether, and HPLC analysis were used for the evaluation of their selectivities towards the three main carotenoids with regard to different biomass pre-treatment. The average Cmax values (maximum concentration of caronoids in a specific solvent) were estimated to 16 mg/L with the five out of eight solvents investigated, whereas methanol, pentane, and hexane gave lower values of 10, 11, and 9 mg/L, respectively. The highest carotenoid yield was obtained in the case of wet biomass, where 44–56% is recovered with one solvent and three extractions and the rest is recovered only after subsequent treatment with acetone; thus, four extractions of 2.5 h are needed. Two extractions of 54 min are enough to recover carotenoids from dehydrated biomass, with the disadvantage of a high degree of degradation. Our results showed that, for maximum carotenoid recovery, ethyl ether, 2-propanol, and ethanol could be successfully used with biomass without prior treatment, whereas fractions enriched in β-carotene or lycopene can be obtained by extraction with the proper solvent, thus avoiding degradation due to time-consuming processes.  相似文献   

19.
Abstract

All four diastereoisomers of 3-thymine-1-(tbutoxycarbonyl)aminocyclopentane- 1-carboxylic acid have been synthesised from (S)-dimethyl malate and thymine monomer 12 has been incorporated into an α-cycloPNA oligomer.  相似文献   

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