首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Fifty-eight species and one variety belonging to 25 genera were collected from the atmosphere of Taif from August 1981 to July 1982 (12 exposures for each type of media) on glucose- and cellulose-Czapek's agar plates at 28 °C.The total counts of sugar and cellulose-decomposing airborne fungi showed seasonal fluctuations; the maxima were recorded in winter, and the minima in summer months. Aspergillus (16.23% and 13.22% of total fungi on glucose and cellulose media, respectively), Alternaria (11.52% and 15.7%), Cladosporium (18.59% and 9.5%), Drechslera (4.7% and 10.74%), Scopulariopsis (7.33% and 6.6%) and phoma (8.12% and 11.98%) were recovered in high seasonal occurrence on the two media. Also, Penicillium (on glucose) and Ulocladium (on cellulose) were common in the air accounting for 10.73% and 7.44% of total fungi, respectively.  相似文献   

2.
Twenty two plants were collected from Taif Governorate and identified as: Euphorbia glomerifera, Juniperus procera, Launaea mucronata, Capparis dcidua, Punica granatum, Opuntia ficus, Prunus persica, Eucalyptus globulus, Medicago sativa, Artemisia monosperma, Trichodesma calathiforme, Artemisia judaica, Foeniculum vulgare, Phagnalon sinaicum, Rumex dentatus, Asphodelus aestives, Pulicaria crispa, Launae sonchoides, Forsskaolea tenacissima, Arnebia hispidissima, Avena spp and Aerva lanata. Pathogenic fungi were isolated from some of these plants and identified as Alternaria alternate, Ulocladium botrytis, Cladosporium spp, Cephalosporium spp, Penicillium chrysogenum, Fusarium oxysporum and Humicola grisea. Four antagonistic isolates were tested, 2 from Gliocladium fungus and 2 from Trichoderma fungus. We found that all the four antagonistic isolates (G. deliquescens, G. virens, T. viride and T. hamatum) significantly inhibited the radial growth of the pathogenic fungi tested, with different ratios. The results indicated that the antibiotics produced by the antagonists were more effective than the fungus itself and differ with different fungi.Coating plant stems with antagonists or with antagonist extracts reduce the severity of the disease but not prevent it in all tested pathogens.  相似文献   

3.
Thirty-four genera and 80 species in addition to one variety of A. nidulans were identified from 40 soil samples colleted from different places in desert of Saudi Arabia. More than forty-two species are new records from Saudi Arabian soils. Aspergillus and Penicillium contributed the greatest number of species (15 species + 1 variety and 13 species respectively).The most frequent genera were Aspergillus, Penicillium, Botryotrichum, and Ulocladium followed by Macrophomina, Rhizopus, Fusarium, Alternaria and Cladosporium from which A. fumigatus, A. terreus, A. niger, A. flavus, P. citrinum, P. corylophilum, B. atrogriseum, U. botrytis, M. phaseoli, R. stolnifer, F. moniliforme, A. alternata and C. herbarum were the most common.Comparison between the present results and those of the other studies showed that there is no fungal flora characteristic of desert soils of Saudi Arabia.  相似文献   

4.
Viable airborne fungi in Riyadh, Saudi Arabia   总被引:3,自引:4,他引:3  
An aerobiological study to identify and quantify allergenic fungi and their seasonal fluctuations was conducted at two different sites, (Al-Batha, a more developed area in the south and Al-Ulia, a less developed area in the north) in Riyadh city, using portable Personal Volumetric Air Sampler (Burkard Manufacturing Co., England). Sampling was conducted twice a week in both the morning and in the afternoon at both sites, for a period of 12 months. Airborne fungi were grouped into major and minor components depending upon their frequency of appearance and catch percentage in the air. Cladosporium spp., Penicillium spp., Aspergillus spp., Alternaria spp. and Ulocladium spp. were included as major components. Minor components included Drechslera spp., Rhizopus spp., Fusarium spp. and Stachybotryis spp. In general, higher concentrations of fungi were found at the developed (Al-Batha) site than at the less developed (Al-Ulia) site, both in the morning and in the afternoon.  相似文献   

5.
Six different varieties of date-palm viz. Sukhari, Saggae, Rotana, Kholasi, Rashoodia and Nabtat Ali, were screened for seed-borne fungi. Eleven species belonging to nine different genera of fungi were isolated. The genera isolated were Alternaria, Eurotium, and Fusarium (two species), Aspergillus, Drechslera, Penicillium, Rhizopus, and Curvularia (one species each). This is the first record of seed-borne fungi from Phoenix dactyliera L. in Saudi Arabia.  相似文献   

6.
Fungi causes most plant disease. When fruits are stored at suboptimal conditions, fungi grows, and some produce mycotoxin which can be dangerous for human consumption. Studies have shown that the Penicillium and Monilinia species commonly cause spoilage of fruits, especially apples. Several other genera and species were reported to grow to spoil fruits. This study was conducted to isolate and identify fruit spoilage by fungi on apples collected in Riyadh, Saudi Arabia and conduct a molecular identification of the fungal isolates. Thus, we collected 30 samples of red delicious and Granny Smith apples with obvious spoilage from different supermarkets between February and March of 2012 in Riyadh, Saudi Arabia. Each apple was placed in a sterile plastic bag in room temperature (25–30 °C) for six days or until fungal growth was evident all over the sample. Growth of fungal colonies on PDA was counted and sent for molecular confirmation by PCR. Six fruit spoilage fungi were isolated, including Penicillium chrysogenum, Penicillium adametzii, Penicillium chrysogenum, Penicillium steckii, Penicillium chrysogenum, and Aspergillus oryzae. P. chrysogenum was the most frequent isolate which was seen in 14 of a total of 34 isolates (41.2%), followed by P. adametzii and A. oryzae with seven isolates each (20.6%) and the least was P. steckii with six isolates (17.6%). Penicillium species comprised 27 of the total 34 (79.4%) isolates. Sequence analysis of the ITS regions of the nuclear encoded rDNA showed significant alignments for P. chrysogenum, P. adametzii and A. oryzae. Most of these fungal isolates are useful and are rarely pathogenic; however they can still produce severe illness in immune-compromised individuals, and sometimes otherwise healthy people may also become infected. It is therefore necessary to evaluate the possible production of mycotoxins by these fungi to determine a potential danger and to establish its epidemiology in order to develop adequate methods of control.  相似文献   

7.
BackgroundDermatophytes are a scientific label for a group of three genera (Microsporum, Epidermophyton and Trichophyton) of fungus that causes skin disease in animals and humans. Conventional methods for identification of these fungi are rapid and simple but are not accurate comparing to molecular methods.ObjectiveThis study aimed to isolate human pathogenic dermatophytes which cause dermatophytosis in Riyadh City, Saudi Arabia and to identify these fungi by using conventional and molecular methods.MethodsThe study was conducted in Medical Complex, Riyadh and King Saud University. Samples of infected skin, hairs and nails were collected from 112 patients. Diagnosis of skin infections, direct microscopic test, isolation and identification of dermatophytes by conventional and molecular methods were carried out.ResultsThe results indicated that the tinea capitis infection had the highest prevalence among the patients (22.3%) while Tinea barbae had the lowest. In this study the identified dermatophyte isolates belong to nine species as Trichophyton violaceum, Trichophyton verrucosum, Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton schoenleinii, Trichophyton concentricum, Microsporum canis, Microsporum audouinii and Epidermophyton floccosum which cause skin infections were isolated during this study. Non dermatophyte isolates included 5 isolates from Aspergillus spp. 4 isolates from Acremonium potronii and 15 isolates from Candida spp. M. canis were the most common species (25% of isolated dermatophytes). Out of the 52 dermatophyte isolates identified by conventional methods, there were 45 isolates identified by the molecular method.ConclusionsThe results concluded that approximately M. canis caused a quarter of dermatophyte cases, tinea capitis infection was prevalent and the molecular method was more accurate than conventional methods.  相似文献   

8.
Twenty-five genera and sixty-eight species, in addition to one variety of each of A. chevalieri, A. flavus and A. nidulans were isolated from 40 soil samples collected from desert in Saudi Arabia on 5% sodium chloride-Czapek's agar. The most frequent genera were Aspergillus (20 species + 3 varieties), Penicillium (14 species), Drechslera (2 species) and Ulocladium (3 species), followed by Stemphylium (1 species), Scopulariopsis (2 species), Trichoderma (1 species) Botryotrichum (2 species), Cladosporium (3 species), Myrothecium (1 species) and Alternaria (1 species). From these genra A. amstelodami, A. chevalieri, A. ruber, A. ochraceus, P. brevi-compactum, P. ?cyano-fulvum, P. notatum, D. spicifera, U. consortiale, S. botryosum, S. brevicaulis, T. viride, B. piluliferum, C. herbarum, M. verrucaria and A. alterata were the most common. The results obtained in this investigation reveal that the fungus flora of Saudi Arabian soils is of halophilic nature.  相似文献   

9.
Using the dilution-plate method, 27 genera and 64 species were collected from 20 air-dust samples on glucose — (24 genera and 57 species) and cellulose — (21 genera and 45 species) Czapek's agar at 28 °C. There are basic similarities between the mycoflora of air-dust on the two media and the most prevalent species were Aspergillus niger, A. flavus, A. ochraceus, A. terreus, A. versicolor, Penicillium chrysogenum, P. funiculosum, Alternaria alternata, Cladosporium herbarum, Fusarium oxysporum, Rhizopus stolonifer and Trichoderma viride. Chaetomium globosum, Stachybotrys chartarum, Humicola grisea and Arthrobotrys oligospora were common only on cellulose agar plates.Extracts of mycelium from 25 isolates were tested with brine schrimp (Artemia salina); of these 23 displayed varying degrees of toxicity. Thin layer Chromatographic analysis of 12 isolates of Aspergillus flavus revealed that 4 strains were producing detectable aflatoxin. Zearalenone production was noted for 3 out of 5 strains of Fusarium oxysporum and 2 out of 5 strains of F. solani.  相似文献   

10.
Seventy-five species in addition to 5 varieties of cellulose-decomposing which belong to 27 genera were collected during this investigation. Aspergillus (12 species + 4 varieties), Alternaria (4 species), Stachybotrys (3 species + 1 variety), and Penicillium (12 species) were of high frequency of occurrence, of which A. fumigatus, A. niger, A. terreus, A. alternata, A. tenuissima, S. atra, P. citrinum and P. corylophilum were the most common. Six genera were of moderate frequency and these were Botryotrichum (2 species), Macrophomina (1 species), Drechslera (5 species), Ulocladium (4 species), Chaetomium (7 species) and Curvularia (4 species) of which B. atrogriseum, D. spicifera, D. sativus, Ubotrytis, C. spirale and C. lunata were the most prevalent. Five and twelve genera were recovered on cellulose-Czapek's agar plates in low and rare frequency of occurrence, respectively.  相似文献   

11.
Germination bioassay was carried out to test the biological activity of Achillea santolina L. (ASAE), Artemisia monosperma Del. (AMAE), Pituranthus tortuosus L. (PTAE) and Thymus capitatus L. (TCAE) aqueous extracts (collected from Taif region, KSA) on germination percentage (GP), plumule (PL) and radicle (RL) lengths (mm) besides seedling dry weight (SDW) (mg/seedlings) of Medicago polymorpha L. The inhibitory effect of P. tortuosus was insignificant compared to the other three donor species which attained the strongest allelopathic potential in the following order: A. santolina > A. monosperma > T. capitatus. Growth experiment using crude powder of the four donor species was conducted to examine their effects on leaf area index (LAI), photosynthetic pigments, total available carbohydrates (TAC) and total protein (TP). It is worth mentioning that each of the four donor species crude powders mixed with clay loam soil appeared to have a great inhibitory allelopathic effect on LAI, total photosynthetic pigment and chlorophyll a (Chl a) while carotenoids exhibited a slight increase with the application of the four donor species crude powders. TAC and TP were significantly decreased with increasing the crude powder concentrations while a slight decrease was recorded for carbon/nitrogen (C/N) ratio. There is possibility of using these allelochemicals directly or as structural leads for the discovery and development of environmentally friendly herbicides to control weeds. The study recommended that these species must be phytochemically examined in future for their allelochemicals in order to provide information on the possibilities of using one or more of these species as bioherbicides.  相似文献   

12.
13.
Seed-borne fungi from seeds of barley, canary, maize, oats, rice, rapeseed, red millet, sunflower, white millet and yellow millet were investigated. These seeds are available in the market as bird feed, supplied by companies in various countries as healthy and nutritious food for domestic birds. A total of 81 fungal species were isolated. The genusAspergillus was predominant with 23 species, followed byPenicillium with 18,Ulocladium with 7,Alternaria with 6 andChaetomium, Curvularia andDrechslera with 5 species each. Other genera isolated wereAureobasidium, Cladosporium, Fusarium, Mucor, Rhizopus andSyncephalastrum.  相似文献   

14.
Forty-eight thermophilic and thermotolerant species in addition to 5 varieties which belong to 24 genera were collected from desert soils in Saudi Arabia on glucose-(22 genera and 38 species + 5 varieties), cellulose-(15 genera and 27 species + 4 varieties) and 40% sucrose-Czapek's agar plates (13 genera and 26 species + 4 varieties) at 45 °C. The most frequent species were as follows: Aspergillus fumigatus, A. terreus, Humicola grisea var. thermoidae and Chaetomium thermophile var. copropile on glucose-; A. fumigatus, C. thermophile var. copropile, A. terreus, A. nidulans and C. thermophile var. dissitum on cellulose-; and A. fumigatus and A. terreus on 40% sucrose-Czapek's agar plates. Sixteen species and 4 varieties were particularly thermophilic and these were A. fumigatus, H. grisea var. thermoidae, H. insolens, H. lanuginosa, C. thermophile var. copropile, C. thermophile var. dissitum, C. virginicum, M. pusillus, S. thermophila, S.? pulverulentum, T. thermophilus, T.? emersoni, T. aurantiacus, T. thermophila, M. pulchella var. sulfurea, M. albomyces, ?A. terrestris, C. pruinosum, T. thermophila and P. thermophila. The remaining species showed different degrees of thermotolerant (32 species + 1 variety).  相似文献   

15.
16.
One hundred samples of tomato seeds were collected in 2011 and 2012 from tomato-cultivated fields in Saudi Arabia and screened for their seed-borne mycoflora. A total of 30 genera and 57 species of fungi were recovered from the collected seed samples using agar plate and deep-freezing blotter methods. The two methods differed as regards the frequency of recovered seed-borne fungi. Seven fungi among those recovered from tomato seeds, which are known as plant pathogens, were tested for their pathogenicity and transmission on tomato seedlings. The recovery rate of these pathogens gradually decreased from root up to the upper stem, and did not reach to the stem apex. The distribution of tomato seed-borne fungi was also investigated throughout Saudi Arabia. In this concern, Al-Madena governorate recorded the highest incidence of fungal flora associated with tomato seeds. The impact of meteorological variables on the distribution of tomato seed-borne mycoflora was explored using the ordination technique (canonical correspondence analysis). Among all climatic factors, relative humidity was the most influential variable in this regard. Our findings may provide a valuable contribution to our understanding of future global disease change and may be used also to predict disease occurrence and fungal transfer to new uninfected areas.  相似文献   

17.
As the demand for biofuels for transportation is increasing, it is necessary to acquire technologies that will allow affordable production of biodiesel. Conventional biodiesel is mainly produced from vegetable oil by chemical transesterification, but this product has relatively low yield and is competing with agricultural land that can be used for food production. In the present study, 14 filamentous fungi were isolated from different types of soil from Al-Hassa, Saudi Arabia. Nile red staining revealed that lipid bodies were present in 6 of the 14 fungal isolates. Lipid extraction showed that 3 fungi were able to accumulate lipid >20% (wt/wt) of their dry cell mass (0.59–2.40 g/L). The profile of fatty acids revealed a high content of oleic (C18:1, n9), palmitic (C16:0) and linoleic (C18:2) acids similar to conventional vegetable oils used for biodiesel production. Isolate RY4, with the highest lipid yield was identified as Mucor circinelloides based on morphological characteristics confirmed with 18S rRNA gene sequencing. Sequence data of nucleotides were obtained from DNA sequencing submitted to GenBank [GenBank: AB916546.1]. Certain oil compounds were determined by FTIR spectroscopy.  相似文献   

18.
One-hundred and eleven species and three species varieties belonging to 39 genera were collected from 50 dust samples on the five media used at 28°C. Using the hair-baiting technique with horse hair, 10 species ofChrysosporium were isolated:C. asperatum, C. state ofArthroderma tuberculatum, C. indicum, C. inops, C. keratinophilum, C. merdarium, C. pannorum, C. queenslandicum, C. tropicum andC. xerophilum. True dermatophytes were isolated:Trichophyton verrucosum andTrichophyton sp. Also, numerous fungi tolerating high levels of cycloheximide were encountered, such as members ofAcremonium, Aspergillus andPenicillium. On plates of glucose or cellulose Czapek-Dox agar (free from sucrose) the most frequent fungi were:Alternaria alternata, Aspergillus flavus, A. flavus var.columnaris, A. fumigatus, A. niger, A. ochraceus, A. sydowii, A. terreus, Chaetomium globosum, Cladosporium herbarum, Emericella nidulans, Fusarium oxysporum, Mucor hiemalis, Penicillium chrysogenum, P. oxalicum, Scopulariopsis brevicaulis andUlocladium atrum. On plates of 50% sucrose or 10 and 20% NaCl-Czapek's agar, some interesting species were frequently encountered:Eurotium amstelodami, E. chevalieri, E. halophilicum, E. montevidensis, E. repens, E. rubrum andScopulariopsis halophilica. The isolated, fungi have been tested for osmophilicity and halophilicity, they showed different rates of growth on sucrose and sodium chloride-Czapek's medium of various osmotic potential.  相似文献   

19.
Three levels of hamadryas social structure—the one male unit (OMU), the band, and the troop—have been observed at all sites studied, but a fourth—the clan—has been observed at only one site, Erer-Gota, Ethiopia, during a longitudinal check of the dispersion of identified individuals. The clan is important since it appears to provide the basis for male philopatry, although comparative data is needed from other sites to confirm this. We studied a huge commensal group of hamadryas baboons (over 600 animals) in Saudi Arabia. We put ear tags on baboons between 1998 and 2004 and analyzed social structure, relying on the interactions of these tagged animals by focusing especially on their dispersal patterns from OMUs. OMU membership tended to be looser than that of the Ethiopian hamadryas. Females tended to shift between OMUs on an individual basis in our study group, whereas the collapse of an OMU was a major occasion of adult female transfer in Ethiopia. We found neither stable bands (a “band” in our study group was defined as a regional assemblage of OMUs) nor clans that lasted for several years. Some OMUs moved and transferred into neighboring areas over both the short and long term. Further, some post-adolescent males appeared to move out of the study area. The ratio of adult females in an OMU in our study group was larger than for any other documented study site, and this may be the reason for enhanced female transfer between OMUs. A large proportion of the adolescent females showed no clear membership to OMUs, and no “initial units” (commonly observed in Ethiopia) were discernible. The ease with which young males acquired adult females at the study site must have disrupted the formation of a clan, a “male-bonded society.”  相似文献   

20.
Mangrove sediments were collected from major mangrove stands on the Red Sea Coast of Saudi Arabia. Forty five isolates belonging to 12 genera were purified and five isolates as well as their consortium were found to be able to grow in association with petroleum oil as sole carbon source under in vitro conditions. The isolated strains were identified based on internal transcribed spacer (ITS) rDNA sequence analysis. The fungal strains with the greatest potentiality to degrade diesel oil, without developing antagonistic activity, were identified as Alternaria alternata, Aspergillus terreus, Cladosporium sphaerospermum, Eupenicillium hirayamae and Paecilomyces variotii. As compared to the controls, these fungi accumulated significantly higher biomass, produced extracellular enzymes and liberated larger volumes of CO2. These observations with GC–MS data confirm that these isolates displayed rapid diesel oil bioremoval and when used together as a consortium, there was no antagonistic activity.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号