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1.
Original data on the survival of fungal spores exposed to space conditions are presented. The experiment was carried out on the Earth-orbiting Russian satellite Foton-M4. The flight duration of the satellite was 45 days. Thirteen fungal species (hyaline as well as pigmented) from 10 genera recovered from destructed stone materials were studied. Sterile quartz sand was inoculated by the fungal spores and was placed into Eppendorf tubes. During the space flight, the Eppendorf tubes with fungal spores were kept inside the Foton descent capsule in the “Biokont” containers and on the external surface of the capsule in the “Exobiofrost” containers exposed to the open space as well. Spores of ten species (77% of all tested species), i.e. Acremonium charticola, Aspergillus niger, Aspergillus versicolor, Chaetomium globosum, Cladosporium sphaerospermum, Penicillium chrysogenum, Penicillium verrucosum, Purpureocillium lilacinum, Sarocladium kiliense, and Trichoderma harzianum, survived after the flight both inside and outside the descent capsule. Only three species (23% of all tested species), i.e. Acremonium furcatum, Engyodontium album and Verticillium zaregamsianum, failed to survive outside as well as inside the capsule. Spore viability differed depending on the fungal species. Thus, spores of some fungal species are able to survive under the complex of stress factors such as low temperature values, radiation, etc. We have shown that micromycetes can be used as a model group for study of eukaryotic organisms’ resistance to stress factors, due to their high tolerance not only to extreme terrestrial environments, but to the extraterrestrial ones as well.  相似文献   

2.
This paper is the first aero-mycological report from Demänovská Ice Cave. Fungal spores were sampled from the internal and external air of the cave in June, 2014, using the impact method with a microbiological air sampler. Airborne fungi cultured on PDA medium were identified using a combination of classical phenotypic and molecular methods. Altogether, the presence of 18 different fungal spores, belonging to 3 phyla, 9 orders and 14 genera, was detected in the air of the cave. All of them were isolated from the indoor samples, and only 9 were obtained from the outdoor samples. Overall, airborne fungal spores belonging to the genus Cladosporium dominated in this study. However, the spores of Trametes hirsuta were most commonly found in the indoor air samples of the cave and the spores of C. herbarum in the outdoor air samples. On the other hand, the spores of Alternaria abundans, Arthrinium kogelbergense, Cryptococcus curvatus, Discosia sp., Fomes fomentarius, Microdochium seminicola and T. hirsuta were discovered for the first time in the air of natural and artificial underground sites. The external air of the cave contains more culturable airborne fungal spores (755 colony-forming units (CFU) per 1 m3 of air) than the internal air (from 47 to 273 CFU in 1 m3), and these levels of airborne spore concentration do not pose a threat to the health of tourists. Probably, the specific microclimate in the cave, including the constant presence of ice caps and low temperature, as well as the location and surrounding environment, contributes to the unique species composition of aeromycota and their spores in the cave. Thus, aero-mycological monitoring of underground sites seems to be very important for their ecosystems, and it may help reduce the risk of fungal infections in humans and other mammals that may arise in particular due to climate change.  相似文献   

3.
While symbiotic fungi play a key role in the growth of endangered Calanthe orchid species, the relationship between fungal diversity and Calanthe species remains unclear. Here, we surveyed root associated fungal diversity of six Calanthe orchid species by sequencing the internal transcribed spacer (ITS) region using 454 pyrosequencing. Our results revealed that Paraboeremia and Coprinopsis are dominant fungal genera among Calanthe species. In terms of overall relative abundance, Paraboeremia was the most common fungal genus associated with Calanthe roots, followed by Coprinopsis. Overall fungal diversity showed a significant degree of variation depending on both location and Calanthe species. In terms of number of different fungal genera detected within Calanthe species, C. discolor had the most diverse fungal community, with 10 fungal genera detected. This study will contribute toward a better understanding of those fungi that are required for successful cultivation and conservation of Korean Calanthe species.  相似文献   

4.
The ambient atmosphere is dominated with pollen and spores, which trigger allergic reactions and diseases and impact negatively on human health. A survey of pollen and fungal spores constituents of the atmosphere of Garki, Abuja (North-Central Nigeria) was carried out for 1 year (June 1, 2011–May 31, 2012). The aim of the study was to determine the prevalence and abundance of pollen and fungal spores in the atmosphere and their relationship with meteorological parameters. Airborne samples were trapped using modified Tauber-like pollen trap, and the recipient solutions were subjected to acetolysis. Results revealed the abundance of fungal spores, pollen, fern spores, algal cysts and diatoms in decreasing order of dominance. The atmosphere was qualitatively and quantitatively dominated by pollen during the period of late rainy/harmattan season than the rainy season. Numerous fungal spores were trapped throughout the sampling periods among which Alternaria spp., Fusarium spp., Cladosporium spp. and Curvularia spp. dominated. These fungi have been implicated in allergic diseases and are dermatophytic, causing diverse skin diseases. Other pathogenic fungi found in the studied aeroflora were Dreschlera spp., Helminthosporium spp., Torula spp., Pithomyces spp., Tetraploa spp., Nigrospora ssp., Spadicoides spp., Puccinia spp. and Erysiphe graminis. Total pollen and fungal spores counts do not show significant correlation with meteorological parameters.  相似文献   

5.
Aspergillus species are highly abundant fungi worldwide. Their conidia are among the most dominant fungal spores in the air. Conidia are formed in chains on the vesicle of the asexual reproductive structure called the conidiophore. Here, it is shown that the velvet protein VeA of Aspergillus niger maximizes the diameter of the vesicle and the spore chain length. The length and width of the conidiophore stalk and vesicle were reduced nearly twofold in a ΔveA strain. The latter implies a fourfold reduced surface area to develop chains of spores. Over and above this, the conidial chain length was approximately fivefold reduced. The calculated 20-fold reduction in formation of conidia by ΔveA fits the 8- to 17-fold decrease in counted spore numbers. Notably, morphology of the ΔveA conidiophores of A. niger was very similar to that of wild-type Aspergillus sydowii. This suggests that VeA is key in conidiophore architecture diversity in the fungal kingdom. The finding that biomass formation of the A. niger ΔveA strain was reduced twofold shows that VeA not only impacts dispersion capacity but also colonization capacity of A. niger.  相似文献   

6.
Introduction Fungal spores constitute an important fraction of bioaerosols in the atmosphere. Objectives To analyse the content of Alternaria and Cladosporium spores in the atmosphere of Beja and the effect of meteorological conditions on their concentrations. Methodology The daily and hourly data of Alternaria and Cladosporium fungal spores concentration in the atmosphere of Beja were monitored from April 12, 2012 to July 30, 2014, based on the Portuguese Aerobiology Network methodology. The influence of meteorological conditions on the studied types of fungal spore concentrations was assessed through Spearman’s correlation analysis. Results During the study period, 20,741 Alternaria spores and 320,862 Cladosporium spores were counted. In 2013, there were 5,822 Alternaria spores and 123,864 Cladosporium spores. The absolute maximum concentrations of Alternaria and Cladosporium spores were recorded on November 8, 2013, with 211 and 1301 spores/m3, respectively. Temperature, insolation and wind direction parameters showed a positive correlation with Alternaria and Cladosporium spore levels, while relative humidity and precipitation presented a negative correlation, which is statistically significant. Wind speed only showed a statistically significant positive correlation in terms of Alternaria spore levels. Conclusion Alternaria and Cladosporium spores are present in the atmospheric air of Beja throughout the year, with the highest concentration period occurring during spring and autumn. There was a clear effect of meteorological parameters on airborne concentrations of these fungal spores.  相似文献   

7.
The impact of climate change on fungal growth and spore production is less well documented than for allergenic pollen grains, although similar implications for respiratory tract diseases in humans occur. Fungal spores are commonly described as either “dry” or “wet” according to the type of weather associated with their occurrence in the air. This study examined the distribution of selected fungal spores (Alternaria spp., Cladosporium spp., Didymella spp., Epicoccum spp., Leptosphaeria spp. and rusts) occurring in the West Midlands of UK during 2 years of contrasting weather. Spore specimens were collected using a 7-day volumetric air sampler and then analysed with the aid of light microscopy. Distributions of spores were then studied using normality tests and Mann–Whitney U test, while relationships with meteorological parameters were investigated using Spearman’s rank test and angular-linear correlation for wind direction analysis. Our results showed that so-called wet spores were more sensitive to the weather changes showing statistically significant differences between the 2 years of study, in contrast to “dry” spores. We predict that in following years we will observe accelerated levels in allergenic fungal spore production as well as changes in species diversity. This study could be a starting point to revise the grouping system of fungal spores as either “dry” or “wet” types and their response to climate change.  相似文献   

8.
In Uruguay, aeromycological studies are restricted to a gravimetric analysis performed from December 1942 to March 1944 in Montevideo where spores of Pucciniaceae, Alternaria and Helminthosporium were the only specimens identified. Daily monitoring of airborne fungal spores was carried out for the first time in Montevideo, from April 2012 to March 2014, using a Rotorod sampler in order to evaluate the seasonal variation and influence of meteorological parameters. A total of 548,309.68 spores/m3 were recorded which belong to anamorphs of Higher Fungi (69.18 %), Phyla Ascomycota (12.62 %), Basidiomycota (8.01 %), Oomycota (0.37 %) and Myxomycota (0.06 %). Airborne spores occurred in Montevideo throughout the whole year. However, a seasonal pattern was revealed, with the highest concentrations recorded in autumn and summer. The most abundant spore types were Cladosporium (53.22 %), Alternaria (6.62 %), Didymella Group (5.86 %), Leptosphaeria Group (4.37 %) and Coprinus (4.3 %). Temperature appeared to be the most influential meteorological factor correlating significantly and positively with total spore, Cladosporium, Alternaria and Didymella Group abundance. Relative humidity influenced positively total spore, Cladosporium and Didymella Group concentrations while a weak negative association was obtained for Alternaria. Wind speed correlated negatively with total spore, Cladosporium, Alternaria and Didymella Group. Precipitation showed a negative influence on Alternaria, while positive correlations were observed for Didymella Group. For the first time, fungal spores considered allergenic were recorded in Montevideo atmosphere and the risk of exposure would have been high from December to June. However, long-term sampling is needed to define seasonal prevalence patterns and the influence of meteorological conditions on spore abundance.  相似文献   

9.
The aim of this paper was to make a first approximation of the fungal spore airborne content in Valladolid along the year, constructing the first spore calendar for the middle-west of Spain. So that, we monitored the city during 2005 and 2006, being Cladosporium the most abundant type, present all over the year (together with Pleospora). The greatest atmospheric spore diversity was observed in April in contrast with February. The intra-diurnal pattern for Alternaria, Cladosporium and Dreschlera was very similar with an hourly concentration percentage decreasing along two periods, whereas Coprinus, Ganoderma and Periconia showed a clearly nocturnal pattern. The meteorological parameter that most influenced airborne spore concentrations was temperature, significantly and positively in the case of dry-air spores but negatively for wet-air spores.  相似文献   

10.
Central Himalayan region of India encompasses varied ecological habitats ranging from near tropics to the mid-elevation forests dominated by cool-temperate taxa. In past, we have reported several new records and novel species from Uttarakhand state of India. Here, we assessed genetic variations in three mitochondrial genes, namely, 16S rRNA, cytochrome c oxidase subunit I and cytochrome c oxidase subunit II (COI and COII) in 26 drosophilid species collected along altitudinal transect from 550 to 2700 m above mean sea level. In the present study, overall 543 sequences were generated, 82 for 16S rRNA, 238 for COI, 223 for COII with 21, 47 and 45 mitochondrial haplotypes for 16S rRNA, COI and COII genes, respectively. Almost all species were represented by 2–3 unique mitochondrial haplotypes, depicting a significant impact of environmental heterogeneity along altitudinal gradient on genetic diversity. Also for the first time, molecular data of some rare species like Drosophila mukteshwarensis, Liodrosophila nitida, Lordiphosa parantillaria, Lordiphosa ayarpathaensis, Scaptomyza himalayana, Scaptomyza tistai, Zaprionus grandis and Stegana minuta are provided to public domains through this study.  相似文献   

11.
To better understand the diversity and species composition of arbuscular mycorrhizal fungi (AMF) in mangrove ecosystems, the AMF colonization and distribution in four semi-mangrove plant communities were investigated. Typical AMF hyphal, vesicle and arbuscular structures were commonly observed in all the root samples, indicating that AMF are important components on the landward fringe of mangrove habitats. AMF spores were extracted from the rhizospheric soils, and an SSU rDNA fragment from each spore morph-type was amplified and sequenced for species identification. AMF species composition and diversity in the roots of each semi-mangrove species were also analyzed based on an SSU-ITS-LSU fragment, which was amplified, cloned and sequenced from root samples. In total, 11 unique AMF sequences were obtained from spores and 172 from roots. Phylogenetic analyses indicated that the sequences from the soil and roots were grouped into 5 and 14 phylotypes, respectively. AMF from six genera including Acaulospora, Claroideoglomus, Diversispora, Funneliformis, Paraglomus, and Rhizophagus were identified, with a further six phylotypes from the Glomeraceae family that could not be identified to the genus level. The AMF genus composition in the investigated semi-mangrove communities was very similar to that in the intertidal zone of this mangrove ecosystem and other investigated mangrove ecosystems, implying possible fungal adaptation to mangrove conditions.  相似文献   

12.
Fungi associated with black point were isolated from three highly susceptible wheat genotypes in the North China Plain. The 21 isolates represented 11 fungal genera. The most prevalent genera were Alternaria (isolation frequency of 56.7%), Bipolaris (16.1%), and Fusarium (6.0%). The other eight genera were Curvularia, Aspergillus, Cladosporium, Exserohilum, Epicoccum, Nigrospora, Penicillium, and Ulocladium; their isolation frequencies ranged from 0.8 to 4.8%. The pathogenicity of the isolates was individually assessed in the greenhouse by inoculating wheat plants with spore suspensions. Ten of the 21 isolates caused significantly higher incidences of black point than that the controls. These isolates belonged to eight fungal species (A. alternata, B. sorokiniana, B. crotonis, B. cynodontis, C. spicifera, F. equiseti, E. rostratum, and E. sorghinum) based on morphological traits and phylogenetic analysis. The average incidences of black point in the eight fungal species were 32.4, 54.3, 43.0, 41.9, 37.2, 38.8, 50.1, and 34.1%, respectively. B. sorokiniana and A. alternata were determined to be the most important pathogens in the North China Plain based on fungal prevalence and symptom severity. This study is the first to identify E. rostratum as a major pathogen causing black point in wheat.  相似文献   

13.
Present investigation was undertaken to study the dynamics of relationships between atmospheric fungal spores and meteorological factors in western Romania. The airborne spore sampling was carried out by employing volumetric sampling. A total of nine meteorological parameters were selected for this investigation. During 2008–2010, it was found the same pattern of behaviour in the atmosphere for selected spore types (Alternaria, Cladosporium, Pithomyces, Epicoccum and Torula). The spores occurred in the air throughout the whole year, but maximum concentrations were reached in summer. Cladosporium and Alternaria peak levels were observed in June. Epicoccum peak value was found in September. The relationships between airborne spore concentrations and environmental factors were assessed using the analysis of Spearman’s rank correlations and multiple linear regressions. Spearman’s rank correlation analysis revealed that maximum, minimum and mean temperature, and number of sunshine hours were strongly (p < 0.01) and directly proportional to the concentration of all analysed fungal spores. Negative and significant correlations were with daily mean relative humidity. The variance explained percentage by regression analyses varied between 30.6 and 39.6 % for Alternaria and Cladosporium airborne spores. Statistical methods used in this study are complementary and confirmed stable dependence of Alternaria and Cladosporium spore concentrations on meteorological factors. The climate change parameters either increased temperatures, changed precipitation regimes or a combination of both affected allergenic fungal spore concentrations in western Romania. This study demonstrates the need for investigations throughout the year, from month to month, regarding the correct interpretation of airborne spore relationships with meteorological parameters.  相似文献   

14.
Diaphorina citri (Kuwayama) is a global pest of citrus that transmits the bacteria associated with the disease, Huanglongbing. Entomopathogenic fungi and the parasitoid Tamarixia radiata (Waterston) are important biological control agents of this pest and likely to interact in D. citri populations. As a basis for interaction studies, we determined the susceptibility of nymphs and adults of D. citri and adults of the parasitoid T. radiata to six fungal isolates from the species Beauveria bassiana s.l. (Bals.-Criv.) Vuill. (isolates B1 and B3), Metarhizium anisopliae s.s. (Metsch.) (Ma129 and Ma65) and Isaria fumosorosea Wize (I2 and Pae). We conducted experiments evaluating infection levels in all three insect groups following inoculation with a series of conidial concentrations (1 × 104–1 × 108 conidia mL?1). Results showed that D. citri nymphs and T. radiata were more susceptible to fungal isolates than D. citri adults. Overall, B. bassiana and M. anisopliae isolates caused the greatest infection compared with I. fumosorosea isolates in all three groups of insects. Isolates B1 (B. bassiana) and Ma129 (M. anisopliae) infected a greater proportion of adults and nymphs of D. citri, respectively. Both isolates of B. bassiana caused greater infection in T. radiata compared with isolates of the other fungal species. We propose that isolates B1 and Ma129 are the strongest candidates for control of D. citri. Our results represent the first report of entomopathogenic fungi infecting T. radiata, and the basis for future studies to design a biological control programme that uses both agents more efficiently against D. citri populations.  相似文献   

15.
Fungal endophytes are the most ubiquitous and highly diverse microorganisms that inhabit the interior of healthy plants. They are important in plant ecology and offer untapped potential to improve plant health and productivity in agroecosystems. The endophytic assemblage of avocado is poorly understood; therefore, surveys of fungal endophytes of Persea americana Mill. (Avocado) in South Florida organic and conventional orchards were conducted. A total of 17 endophytic fungal species were recovered from healthy avocado terminal branches. Endophytic fungal species were identified by rDNA sequencing of the internal transcribed spacer (ITS) region, using UNITE Species Hypotheses to reliably assign a taxon name, and determined as belonging to the genera Alternaria, Cladosporium, Colletotrichum, Corynespora, Diaporthe, Lasiodiplodia, Neofusicoccum, Neopestalotiopsis, Phyllosticta, and Strelitziana. Endophyte community assemblage differed between organic and conventional agroecosystems. This is the first report of Alternaria eichhorniae, Cladosporium tenuissimum, Corynespora cassiicola, Colletotrichum alatae, Diaporthe fraxini-angustifoliae, Lasiodiplodia gonubiensis, Neofusicoccum algeriense, Neofusicoccum andinum, Neopestalotiopsis foedans, Phyllosticta capitalensis, and Strelitziana africana as endophytes of avocado. Evaluation using pathogenicity tests on avocado leaves and terminal branches showed that endophytic fungal isolates did not cause disease symptoms.  相似文献   

16.
Ectomycorrhizal (ECM) and ectendomycorrhizal fungal species associated with Pinus montezumae were recorded in 8 year-old trees established in microcosms and compared with those associated with 2 year-old trees, in order to determine their persistence over the long-term. Mycorrhizal root tips were morphologically and anatomically characterized and sequenced. The extension of extramatrical mycelium of ECM fungi with long exploration strategies was evaluated. In total, 11 mycorrhizal species were registered. Seven mycorrhizal species were detected on both 2 and 8 year-old pines: Atheliaceae sp., Rhizopogon aff. fallax, R. aff. occidentalis, Suillus pseudobrevipes, Tuber separans, Wilcoxina mikolae and Wilcoxina rehmii. One species, Thelephora terrestris, was exclusively associated with two year–old seedlings, while Cenococcum geophilum, Pezizaceae sp. and Pyrenomataceae sp. were exclusively found on 8 year-old trees. Atheliaceae sp. was the ECM fungal species that presented the most abundant mycelium. Finally, we report one new fungal species of Pezizaceae occurring as a symbiont of P. montezumae.  相似文献   

17.
Dust storms carry large amounts of plant detritus and microorganisms that may cause diseases in humans, animals or plants. These storms are frequent in Kuwait throughout the year. This research was conducted to identify the fungal species carried by the dust storms in Kuwait, originating from the northwesterly direction, with emphasis on plant pathogens. Fungi were isolated from settled dust samples and identified using established microbiological and molecular approaches. Fungal isolates identified as Fusarium oxysporum from settled dust were examined for pathogenicity using a number of crop plants. In total, 17 genera of fungi were identified in the dust samples. These fungi included plant pathogens or facultative plant parasites that were transported in the dust storms as viable propagules. The most common dust-carried fungi belonged to the genera Fusarium, Alternaria, Ulocladium, Phoma, Aspergillus, Acremonium and Penicillium. The F. oxysporum isolates that had been characterized by partial 18S rRNA gene sequencing were pathogenic, causing root and stem rot in tomato, bean and cucumber, but not squash.  相似文献   

18.
During an arbuscular mycorrhiza fungal spore survey on a primary coastal sand-dune system in Goa on the west coast of India, entrophosporoid spores tightly covered with a dense hyphal mantle were recovered. When intact, the spores, at first sight, seemed to be identical in morphology to those of Sacculospora baltica (originally described as Entrophospora baltica) extracted from Polish maritime sand dunes and, to date, the sole member of the recently described genus Sacculospora in the new family Sacculosporaceae, phylum Glomeromycota. Later detailed morphological studies indicated that both fungi produce two-walled spores but the structure and phenotypic features of components of the outer spore wall in the novel fungus differ considerably from those of S. baltica. Differences between the fungi were subsequently confirmed in the phylogenetic analysis of SSU–ITS–LSU nrDNA sequences. Consequently, we describe the novel species as Sacculospora felinovii sp. nov.  相似文献   

19.
The significance of fungal endophytes in African agriculture, particularly Kenya, has not been well investigated. Therefore, the objective of the present work was isolation, multi-gene phylogenetic characterization and biocontrol assessment of endophytic fungi harbored in tomato roots for nematode infection management. A survey was conducted in five different counties along the central and coastal regions of Kenya to determine the culturable endophytic mycobiota. A total of 76 fungal isolates were obtained and characterized into 40 operational taxonomic units based on the analysis of ITS, β-tubulin and tef1α gene sequence data. Among the fungal isolates recovered, the most prevalent species associated with tomato roots were members of the Fusarium oxysporum and F. solani species complexes. Of the three genes utilized for endophyte characterization, tef1α provided the best resolution. A combination of ITS, β-tubulin and tef1α resulted in a better resolution as compared to single gene analysis. Biotests demonstrated the ability of selected non-pathogenic fungal isolates to successfully reduce nematode penetration and subsequent galling as well as reproduction of the root-knot nematode Meloidogyne incognita. Most Trichoderma asperellum and F. oxysporum species complex isolates reduced root-knot nematode egg densities by 35–46 % as compared to the non-fungal control and other isolates. This study provides first insights into the culturable endophytic mycobiota of tomato roots in Kenya and the potential of some isolates for use against the root-knot nematode M. incognita. The data can serve as a framework for fingerprinting potential beneficial endophytic fungal isolates which are optimized for abiotic and biotic environments and are useful in biocontrol strategies against nematode pests in Kenyan tomato cultivars. This information would therefore provide an alternative or complementary crop protection component.  相似文献   

20.
Seven years of aeromycological study was performed in the city of Funchal with the purpose to determine the anamorphic spore content of this region and its relationship to meteorological factors. The sampling was carried out with a Hirst-type volumetric spore trap following well-established guidelines. A total of 17,586 anamorphic fungal spores were recorded during the studied period, attaining an annual average concentration of 2931 spores m?3. Anamorphic fungal spores were observed throughout the year, although the major peaks were registered during spring (April–June) and autumn period (September–November). The lowest spore levels were recorded between December and February months. Over 14 taxa of anamorphic fungal spores were observed with Cladosporium being the most prevalent fungal type accounting for 78 % of the total conidiospores. The next in importance was Alternaria (5.4 %), Fusarium (4.7 %), Torula (3.9 %) and Botrytis (1.9 %). Temperature was the meteorological parameter that favoured the most release and dispersal of the conidiospores, whereas rainfall revealed a negative effect. Despite the low concentration levels found in our region, the majority of the fungal types identified are described as potential aeroallergens. This study provides the seasonal variation of the conidiospores and the periods when the highest counts may be expected, representing a preventive tool in the allergic sensitization of the population.  相似文献   

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