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1.
In order to contribute to the knowledge of monofloral honeys from northern Africa, a number of 116 honey samples were collected in three areas in the northern region of Algeria and analysed for their melissopalynological characteristics. Fifty-one of them proved to be monofloral and were mainly from four botanical sources: Eucalyptus spp., Hedysarum coronarium, Pimpinella anisum and Citrus spp. The honeys could be differentiated from honeys from neighbouring countries by the presence of specific associated pollen. Besides the main pollen species, the characteristic 12 pollen types in the four monofloral Algerian honeys in this study were: Acacia sp., Brassicaceae, Carduus sp., Centaurea sp., Convolvulus arvensis, Eucalyptus spp., Olea europaea, Papaver rhoeas, Pimpinella anisum, Trifolium spp., Rubus sp. and Vicia sp. Regional differences in the pollen composition were also observed. Characteristic associated pollen grains in the north-western region were Acacia sp., Brassicaceae, Carduus sp. and Centaurea sp., in the central north region Coriandrum sativum, Echium sp. and Trifolium spp. and in the north-eastern region Apiaceae.  相似文献   

2.
In this study, new paleontology and lithology foundations on the Bakhtiari Formation were obtained from Shalamzar area in Zagros basin. A depositional mollasic cycle was divided into Bk1, Bk2 and Bk3 units from the base to the top of the Formation. Bk2, with limestone- and mudstone-dominated deposits, was found to alternate with conglomerates and form a marine succession between the two limestone clast-supported conglomeratic continental units. A diverse fossil association has been described for the first time and consists of foraminifera (Oolina spp., Oolina hexagona, Textularia spp., Spiroloculina spp., Peneroplis spp., Elphidium spp., Planulina sp., Amphistegina spp., Lagena spp. Globigerina spp., Globigerinoides spp., Uvigerina spp., Triloculina spp., Quinqueloculina spp., Spiroloculina spp. Nodosariid., Orbitina spp., Borelis melo, Bolivina spp. and Miogypsina spp.), a gastropod community of Strombus spp., Potamides spp., Turitella spp., Cyprea cf. persica and Pleurotomaria sp. and a higher energy colony of scleractinian corals comprising Porites branching, Porites-encrusting massive Favites spp., Favia spp., Tarbellastrea spp. and Acropora spp. The early–middle Miocene marine level of the Bakhtiari Formation, confirms a nearshore accommodation through a middle shelf and an open coastal lagoon (inner shelf) within a fluvial-dominated delta or open estuary during the last presence of a marine trough in the Zagros basin. This saline to hypersaline shallow marine regime was probably dominated in tropical to subtropical conditions. Palaeobiogeography analysis reflects a last seaway faunal exchange between the area and early–middle Miocene basins of Pakistan, India, Australia, Turkey, Greece, Romania Algeria, Egypt, Italy, France, Portugal and Austrian/Hungarian border, which reconstructs a shallow junction between Zagros basin and Mediterranean Tethys and Indo-pacific Ocean during Burdigalian–Langhian (Badenian) before the terminal Tethyan event in late middle Miocene and Tortonian.  相似文献   

3.
Winter diet composition of brown trout Salmo trutta was quantified from November to March in 35 temperate groundwater‐dominated streams in south‐eastern Minnesota, U.S.A., in relation to stream physical characteristics including drainage area, channel slope and influence of groundwater on stream thermal regime. Aquatic invertebrates made up the majority of S. trutta diet in all streams and sampling periods and individual S. trutta typically had consumed 30 or more prey items at each sampling event. Differences in diet composition were greater among streams than between sampling periods within a stream, with Gammarus spp., Brachycentrus spp., Glossosoma spp., Chironomidae and Physella spp. the most common taxa. Landscape‐scale stream characteristics were not significantly associated with S. trutta consumption or diet composition. Winter was period of significant activity in groundwater‐dominated streams, as S. trutta fed on a variety of aquatic prey taxa highlighting the importance of winter base‐flow in moderating S. trutta populations in seasonally cold catchments.  相似文献   

4.
The relationship between sediment trace metals (Ag, Cd, Cr, Cu, Ni, Pb, Zn) and bioaccumulation in tissue of macrobenthos (Parvilucina tenuisculpta, Tellina spp., Macoma spp., Pectinaria californiensis, Nephtys spp., Glycera spp., Metasychis sp., Euphilomedes spp., and Ampelisca spp.) was described from 1975 to 1985 on the San Pedro Shelf, California. Results indicated that: 1) sediment trace metals were elevated at an ocean outfall station; 2) tissue trace metals were never statistically higher at the outfall compared to a reference station except for Zn in Macoma spp.; 3) there were a few statistically significant associations (r) between tissue and sediment metals, but no consistent trends emerged; 4) peak tissue metal concentrations occurred more frequently in the winter than in the summer.  相似文献   

5.
Anaerobic bacteria isolated from clinical specimens at our clinic from January 1994 to June 1998 were analysed. Anaerobes were usually isolated from secondary infections due to eczema/dermatitis. The majority of anaerobes identified were Peptostreptococcus spp., followed by Propion-ibacterium spp. and Prevotella spp. Among the Peptostreptococcus spp., P. magnus was the species most frequently isolated, followed by P. assaccharolyticus and P. prevotii. Pure or predominant growth of anaerobes was seen for each of the two P. prevotti and two Prevotella spp., strains, and for each of the single P. magnus andPropionibacterium spp. strains isolated. The presence of aerobic as well as anaerobic bacteria is important for choosing the antimicrobial agents to be used. Furthermore, Peptostreptococcus spp. showed high susceptibility to benzylpenicillin, ampicillin, piperacillin and minocycline, Propionibacterium spp. showed high susceptibility to all six antimicrobial agents tested, while Prevotella spp. and Bacteroides spp. showed low susceptibilities to all tested antimicrobial agents, except minocycline. Prevotella spp. was also susceptible to piperacillin.  相似文献   

6.
Investigations on the occurrence of Pythium spp. in soil: I. The isolation of Pythium spp., their distinction to macroscopically characteristics and their determination The aim of the present paper consisted in detection of Pythium spp. directly in the soil. This was possible by using a selective medium and by crumbling smallest particles of agar-covered soil on its surface. On the basis of simple morphologically criteria (growth patterns) this method allows to decide concerning the presence of high and less pathogen or apathogen Pythium spp. in a soil sample within 48 hours. About 700 isolates have been cultivated from hyphal tips, determinated and about 230 tested for pathogenicity to sugar beet seedlings in vitro. Most of the Pythia pathogen to sugar beet belong to P. ultimum Trow followed by P. paroecandrum Drechsler and P. debaryanum sensu Drechsler non Hesse. The taxonomically characteristics are demonstrated by figures of the three species.  相似文献   

7.
The colonization characteristics and diversity of dark septate endophytes (DSE) associated with plants growing in a lead and zinc slag heap with a more than 250-year history in southwestern China were assessed. A total of 117 plant samples belonging to 29 species and 19 families were examined, and 97% (28/29) were colonized by dark septate fungal hyphae or microsclerotia. DSE colonization intensity varied greatly across plant species and also across individuals of the same species, showing a hyphal colonization range of 0.0–35.7%. In total, 38 melanized root-associated fungi with various morphological characteristics were isolated and 82% (31/38) of fungi were closely related to well-known DSE fungi, such as Exophiala spp., Phialophora (= Cadophora) spp., Phialocephala spp., and Leptodontidium spp. Among these, Phialophora and Exophiala were the dominant genera. Our results showed that DSE dominantly colonized the roots of the pioneer plants growing in such an ancient Pb-Zn slag heap. By contributing to metal tolerance and nutrient acquisition, DSE may be integral to the function of metal mine ecosystems.  相似文献   

8.
Previous investigations on Sicilian man made lakes suggested that physical factors, along with the specific morphology and hydrology of the water body, are important in selecting phytoplankton species. In particular, the variations of the z mix/z eu ratio due to the operational procedure to which reservoirs are generally subject were recognised as a trigger allowing the assemblage shift. To investigate if these variations may be considered analogous to those occurring in natural lakes as trophic state and phytoplankton biomass increase, causing a transparency decrease and a contraction of the euphotic depth, phytoplankton were collected in two natural water bodies, one mesotrophic (Lake Biviere di Cesarò) the other eutrophic (Lake Soprano), and compared with those collected in two reservoirs with analogous trophic characteristics (Lake Rosamarina, mesotrophic and Lake Arancio, eutrophic). Particular attention was paid to the dynamics of two key groups: Cyanophytes and chlorophytes. In all four water bodies, transparency mainly depended on chlorophyll level. Annual average value of phytoplankton biomass in the mesotrophic environments was below 2.0 mg l–1, whereas in the eutrophic systems it was well above 10 mg l–1. All water bodies showed the presence of cyanophytes (e.g. Anabaena spp., Anabaenopsis spp., Microcystis spp., Planktothrix spp.) and chlorophytes (e.g. Chlamydomonas spp., Botryococcus spp., Oocystis spp., Scenedesmus spp., Pediastrum spp.), but their relative proportions and body size dimensions were different. In particular, small colonial chlorophytes and large-colony forming cyanophytes were most common in the most eutrophic water bodies, whereas larger colonies of green algae in those with a lower trophic state. The results showed that, under the same climatic conditions, autogenic (increase of biomass, decrease in light penetration and euphotic depth) and allogenic (use of the stored waters, anticipated breaking of the thermocline, increase of the mixing depth) processes may shift the structure of phytoplankton assemblage in the same direction even though the quantity of biomass remains linked to nutrient availability.  相似文献   

9.
The fungal flora of soft fruits in relation to storage and spoilage   总被引:2,自引:0,他引:2  
The fungal population of freshly harvested strawberries, raspberries and blackberries was studied throughout the fruiting seasons and the relative importance of fungi responsible for spoilage of stored fruit from different harvest dates was assessed. Botrytis cinerea, Cladosporium spp., Penicillium spp., Aureobasidium pullulans and Mucor spp. were consistently present on all three fruits while Colletotrichum gloeosporioides and Didymella applanata were prevalent on raspberries only and Epicoccum purpurascens and Alternaria spp. on blackberries only. Botrytis cinerea and Mucor mucedo were the predominant spoilage organisms of all three fruits, although the relative importance of the two fungi changed as the season progressed, especially for strawberries. Rhizopus stolonifer, Cladosporium spp., Penicillium spp. and Colletotrichum gloeosporioides were only of minor importance as spoilage organisms.  相似文献   

10.
Pollen grains in the atmosphere of Didim, collected using a Durham sampler, were investigated in 2004 and 2005. Weekly pollen grains per square centimetre were calculated. Over a period of 2 years, 17,518 pollen grains/cm2 belonging to 40 taxa and unidentified pollen grains were recorded. In 2004, 9,879 pollen grains were counted per cm2, and in 2005 the value was 7,639 per cm2. The majority of pollen grains investigated were Pinus spp. (45.58%), Cupressaceae/Taxaceae (13.49%), Olea spp. (9.19%), Platanus spp. (7.62%), Gramineae (6.33%), Pistacia spp. (4.34%), Morus spp. (3.81%), Quercus spp. (2.02%), Abies spp. (1.39%), and Plantago spp. (1.11%). During the month of April, 40.46% of total pollen grains were recorded. According to our results, pollen season durations for the dominated pollen grains in Didim were: the 7th–33rd weeks for Pinus spp., nearly the whole year except summer for Cupressaceae/Taxaceae, the 17th–29th weeks for Olea spp., the 10th–24th weeks for Platanus spp., the 8th–46th weeks for Gramineae, the 8th–20th weeks for Pistacia spp., the 11th–21st weeks for Morus spp., the 17th–21st weeks for Quercus spp., the 9th–27th weeks for Abies spp., and the 7th–26th weeks for Plantago spp.  相似文献   

11.
Physical constrains such as water discharge, suspended solids and turbidity act as dominant factors in driving the planktonic diatom assemblages of the River Adige (North-Eastern Italy). Two sampling stations, characterised by different hydromorphological features (Cortina all’Adige and Boara Pisani, with torrential and more potamal characteristics, respectively) were sampled fortnightly following an integrated approach encompassing physical, chemical and biological measurements and aiming at identifying the dominant factors controlling the temporal development of the community. A morpho-functional approach was used to classify the diatom assemblages where Morpho-Functional Diatom Groups (MFDG) were defined for diatom genera, according to their morphology, habitat selection and modality of adhesion to river substrate. In the two sampling points, algal growth was never limited by nutrients or zooplankton. The irregular development of MFDG was determined by the stochastic hydrological events and changes in variables related to water discharge (suspended solids and light attenuation). Tychoplanktonic, benthic and drifted taxa (such as Diatoma spp., Encyonema spp., Navicula spp. and Nitzschia spp.) were dominant in the torrential station (Cortina all’Adige), while the contribution of euplanktonic unicellular centric taxa (such as Cyclotella spp., and Stephanodiscus spp.) was higher in the potamal station (Boara Pisani).  相似文献   

12.
Seed mycoflora associated with wheat was studied on different media with a particular reference to Blotter and potato dextrose agar (PDA) procedures of ISTA. Seed-borne fungi, viz. Fusarium moniliforme, Rhizopus spp., Mucor spp., Alternaria alternata, Aspergillus niger, Aspergillus flavus, Curvularia lunata, Drechslera spp, Alternaria spp. and Penicillium spp., were isolated from the variety HD264. Blotter method was found to be the best media for the isolation of mycoflora whether borne externally or internally. Total number and frequency of occurrence of fungi were recorded. The effect of seed treatment with different chemicals and eco-friendly botanicals was analysed on germination, and growth, better percentage of seed germination and reduction in fungal pathogen were due to biochemical seed treatment.  相似文献   

13.
Chen  Xiongwen  Zhou  Guangsheng  Zhang  Xinshi 《Plant Ecology》2003,164(1):65-74
Spatial characteristics of sixteen tree species were analyzed by theinformation from 287 permanent plots in 1986 and 1994 on North East ChinaTransect (NECT). Some species expanded and some retracted theirdistribution extents. Betula costata andPhellodendron amurense spread most fast toward west andeast, respectively. All tolerant tree species extended their frontiers and allintolerant tree species retracted their frontiers except Betulaplatyphylla. The distribution area decreased for all species exceptBetula costata, Juglans mandshurica,Ulmus spp. and Fraxinusrhynchophylla.The patch sizes of Pinus koraiensis, Populusdavidiana, Phellodendron amurense,Juglans mandshurica, Fraxinusmandshurica, Betula dahurica,Picea spp., Abies nephrolepis andLarixolgensis decreased, however, the patch sizes of Quercusmongolica, Betula costata, Acermono, Tilia spp., Ulmusspp., Betula platyphylla and Fraxinusrhynchophylla increased. The frequency pattern of Populusdavidiana, Betula platyphylla,Fraxinus rhynchophylla and Betuladahurica changed significantly(p< 0.05). The dominance pattern ofPopulus davidiana, Tilia spp.,Juglans mandshurica, Betulaplatyphylla, Betula dahurica andAbiesnephrolepis changed significantly(p < 0.05). The spatial correlation betweenspecies changed, such as the spatial correlation between Larixolgensis and Betula platyphylla, Acermono and Ulmus spp. increased. The possiblecause of these changes might be climate change, disturbances and habitat loss.  相似文献   

14.
Survey results during 2010–2011 season revealed that the Meloidogyne spp., Helico–tylenchus spp. and Tylenchorhynchus spp. were the common plant parasitic nematodes in the rhizospheres of sugar beet in El-Behera, El-Fayoum and Beni Sueif Governorates. Aspergillus spp., Aspergillus niger, Fusarium spp., Penicillium spp., Penicillium chrysogenum, Penicillium citrinum, Rhizoctonia spp., Rhizopus nigricans, Trichoderma spp. and others were also the common fungi in the same rhizospheres. The rhizosphere of El-Behera Governorate was highly infected with Meloidogyne spp., Fusarium spp. and Rhizoctonia spp., compared to the rhizospheres of El-Fayoum and Beni Sueif, respectively. Evaluation of five of sugar beet cultivars, viz. Chems, Dema-Poly, DS 9001, Manila and Ras-Poly to infection, with Meloidogyne incognita (root-knot nematode), Fusarium solani and Rhizoctonia solani (root rot disease) was carried out under naturally field infection condition in the Nubariya region, Behera Governorate during 2011–2012 season. Host susceptibility rating revealed that the varieties of Ras-Poly, DS 9001 and Manila can be considered as susceptible, while the varieties of Dema-Poly and Chems can be considered as highly susceptible. Pathological results showed that the varieties of Dema-Poly and Ras-Poly were highly infected with F. solani, while not infected with R. solani. The varieties of DS 9001, Manila and Chems were moderately infected with the two pathogens.  相似文献   

15.
Isavuconazole is a new triazole currently undergoing phase III clinical trials. This compound has shown in vitro activity against a large number of clinically important yeasts and moulds including Aspergillus spp., Fusarium spp., Scedosporium spp., Candida spp., the Zygomycetes and Cryptococcus spp. Similar to voriconazole, reduced in vitro activity is seen against Histoplasma capsulatum. In vivo efficacy has been demonstrated in murine models of invasive aspergillosis and candidiasis. Additionally, there are several potential pharmacokinetic and drug–drug interaction advantages of this compound over existing antifungal agents. This review summarizes existing data that has been either published or presented at international symposia.  相似文献   

16.
17.
During 1971-72 contents from the rumens of twenty-two Chanler's mountain reedbuck (Redunca fulvorufula chanleri Rothschild) collected in the Arthur Cole Ranch near Gilgil, Kenya were examined. Frequency of occurrence of monocots averaged 99.5% of identifiable fragments. Frequency of occurrence of monocots in the ground stratum of the vegetation averaged 94% in the areas where mountain reedbuck were collected. Of the 11 grass classifications (seven to species and four to genus) considered reliably identifiable in rumens, three (Themeda triandra, Hyparrhenia spp., and Cymbopogon pospischilii) were taken more frequently than was expected from their occurrence in the vegetation, six (Aristida spp., Cynodon spp., Eragrostis spp., Harpachne schimperi, Microchlva kunthii, and Tragus berteronianus) were taken less frequently, and two (Bothriochloa insculpta and Enneapogon schimperanus) were taken in approximately the same ratio as they occurred in the ground stratum of the vegetation.  相似文献   

18.
Summary Bacterial isolates from contaminated mint shoot cultures were characterized and identified as a preliminary step in determining an elimination treatment. The 22 bacteria were characterized using biochemical and morphological tests and subjected to sensitivity tests with four antibiotics. The isolates were compared with known organisms and assigned to genera according to similarities in characteristics. Seven isolates were analyzed by fatty acid analysis carried out by a commercial laboratory. Six were classified asAgrobacterium radiobacter; eight asXanthomonas; one each asPseudomonas fluorescens, Micrococcus spp.,Corynebacterium spp., andCurtobacterium spp.; four could not be assigned to genera. Inhibition of growth of the bacteria by most antibiotics was best at pH 7.5. Minimal inhibitory concentration and minimal bactericidal concentrations of gentamicin, rifampicin, streptomycin sulfate, and Timentin varied with genotype.  相似文献   

19.
In the present study, 10 soil samples were collected aseptically from an equal number of areas of the Antarctic in the zone occupied by the 1986–1987 Italian expedition for research on keratinophilic fungi.Of particular interest was the isolation of a pathogenic fungus, Microsporum gypseum, from two sites in the base camp occupied by men and by skuas. Trichophyton terrestre was isolated from a site in which people worked and through which penguins and skuas passed.The most widespread fungal species were members of the genus Chrysosporium. Some of these species were isolated but not identified and this part of the study was still be completed.Another significant finding was the absence of fungi in one sample, while in another the widespread and abundant growth in all the seeded dishes of a single species of Chrysosporium.Other species in genera of general diffusion in many environments were also isolated : Aspergillus spp., Malbranchea sp., Mycelia sterilia spp., Paecilomyces sp., Penicillium spp. and Scopulariopsis spp.  相似文献   

20.
Marcus Lehnert 《Brittonia》2006,58(3):229-244
A summary is presented of all Bolivian species of Cyatheaceae and Dicksoniaceae. In total two species of Dicksoniaceae (Culcita 1 sp.,Dicksonia 1 sp.) and 34 species of Cyatheaceae (Sphaeropteris 1 sp.,Alsophila 5 spp.,Cyathea 26 spp.,Cnemidaria 2 spp.) are known. One hybrid inCyathea is recognized. The endemicCyathea dintelmannii is newly described, andCyathea herzogii from Bolivia and Peru is separated fromCyathea caracasana var.boliviana. Both species are illustrated. An artificial key to the Bolivian species of Cyatheaceae is provided.  相似文献   

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