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Aim To describe the composition, diversity and biogeographical affinities of the foliicolous lichen mycobiota in Valdivian temperate rain forest in southern South America. Location Seven localities in Chile (IX to XI region) and Argentina (Neuquén province). Methods Opportunistic sampling of leaf substrates, identification of taxa, and assignment to distribution types. Results Thirty‐seven species, including three lichenicolous fungi, were found in the studied collections, increasing the number of foliicolous taxa known from Valdivian temperate rain forest to 55. New records for the area include Arthonia cyanea, Byssoloma marginatum, B. subdiscordans, Fellhanera bouteillei, F. dispersa, F. subfuscatula, Gyalectidium caucasicum, G. ciliatum, Logilvia gilva, Porina thaxteri, Strigula nitidula and the lichenicolous A. microsticta, Helicobolomyces lichenicola and Opegrapha sipmanii. Seven taxa are described as new: Enterographa falcata, Gyalectidium chilense, G. plicatum, Gyalideopsis choshuencensis, Porina fulvelloides, Strigula wandae and Trichothelium meridionale ssp. austroamericanum. Conclusions There are unexpected floristic affinities in the foliicolous lichen mycobiota of Valdivian temperate rain forest with those of New Zealand and Tasmania. Three typically foliicolous species clearly belong to an austral element: Caprettia setifera and Badimiella pteridophila, both known previously from New Zealand and Tasmania; and Kantvilasia hians, known already from Tasmania and Valdivian temperate rain forest. Other Southern Hemisphere lichens, such as Parmeliella nigrocincta, P. thysanota and Psoroma caliginosum, are also found commonly on leaves. On the other hand, specific affinities of the foliicolous lichen mycobiota of Valdivian temperate rain forest with the Neotropics are absent: most of the species shared between the two regions belong to a cosmopolitan‐tropical or a circumpacific element. Thus far, nine taxa are endemic to Valdivia. The Valdivian temperate rain forest foliicolous lichen mycobiota is therefore regarded as one of six distinctive regions in the world.  相似文献   

3.
This study focused on the taxonomy and diversity of the endophytic fungi associated with Vellozia gigantea, an endemic, ancient, and endangered plant species that occurs only in the rupestrian grasslands of Brazil. A total of 285 fungal isolates were recovered from leaves and roots of the V. gigantea, which were identified in 27 genera and 87 different taxa using molecular taxonomy methods. Xylaria berteri, Diaporthe sp. 1, Nigrospora oryzae, Muscodor sp. 1, Colletotrichum aeschynomene, and Trichoderma viride occurred in the highest frequency in both the leaf and root. Diaporthe was the most abundant genus, with 70 endophytic isolates recovered from the leaves and roots. Among all the taxa identified, 62 occurred as singlets, including those of the genera Clonostachys, Coccomyces, Crucellisporiopsis, Daldinia, Myxotrichum, Pallidocercospora, Pezicula, Peyronellaea, and Pseudocercospora. The diversity indices displayed high values, showing that V. gigantea shelters a diverse and rich mycobiota. Our results indicate that V. gigantea shelters in its tissues a highly diverse and cryptic mycobiota, including several rare species previously unreported as endophytes, but that are reported to have different ecological functions, which might be an important biological component contributing to the fitness of the plants living in the rupestrian grassland.  相似文献   

4.
本文报道中国假尾孢属的24个种,其中有2个新种:杨桐假尾孢(Pseudocercospora adinandrae Guo&Liu),钟萼假尾孢(Pseudocercospora bretschneiderae Liu&Guo),10个新组合,1个新名称:木豆假尾孢(Pseudoeercospora cajani-flavi Guo&Liu)和11个中国新记录。文中对2个新种提供了拉丁文简介、描述及图。所研究的标本全部保存在中国科学院微生物研究所真菌标本室(HMAS)。  相似文献   

5.
An annotated checklist of 1016 species of fungi (Ascomycota and Basidiomycota), which have been recorded in 95 different localities, from 1990 to 2015, is presented for Umbria (Italy). The checklist was compiled from records of Umbrian fungi in scientific publications, unpublished lists and personal observations. This work represents the first comprehensive checklist of macrofungi for Umbria. Even if not complete, an exhaustive overview of the current knowledge of the mycobiota of Umbria is presented. Although a large amount of the regional territory has still to be explored for mycological diversity, this study offers an important support in compiling red-lists of endangered macrofungi, as well as to identify indicator species of particular habitats to be considered for wildlife reserves, as is currently done in many European countries.  相似文献   

6.
The objective of this study was to determine the genetic relatedness among the Cercospora and Pseudocercospora species closely related to Cercospora apii by using a polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) analysis of the internal transcribed spacer (ITS) region. A single PCR fragment (about 550 bp) was obtained from all Cercospora species categorized as the C. apii-group, Pseudocercospora purpurea, Pseudocercospora conyzae, and Pseudocercospora cavarae. Cercospora caricis yielded a 680 bp PCR fragment. The similarity in the PCR fragment size and RFLP profiles among the C. apii-group isolates, including Pseudocercospora purpurea, and Pseudocercospora conyzae strongly suggests that these species are conspecific. Synonymy with C. apii (lectotype) at a subspecific rank has been proposed. Amplified ITS regions of genomic DNA extracted from spinach leaves showing 12 and 233% leaf spot disease symptoms caused by Cercospora beticola yielded two PCR fragments (i.e., one from the fungus and one from the host plant) and were resolved by electrophoresis of the PCR product in 3% LMP agarose. Digestion of the total PCR product with HinfI restriction enzyme yielded RFLP profiles similar to those obtained from amplified DNA from the causative agent, C. beticola. The method described in this preliminary study offers rapid detection and diagnosis of fungal infections in plants for disease prediction and management and screening of plant materials for quarantine purposes.  相似文献   

7.
Mediterranean ecosystems have not been consistently investigated as natural habitats for microbes in general, and fungi in particular. Here we present the results of a survey of epiphytic mycobiota (filamentous fungi and yeasts) on the phylloplane of selected plants in the Arrábida Natural Park, an ecosystem of Mediterranean characteristics in Portugal, using conventional culture-dependent isolation methods. Leaves from the species Acer monspessulanum and Quercus faginea (deciduous trees) and Cistus albidus, Pistacia lentiscus, and Osyris quadripartita (evergreen shrubs) were collected twice a year for two consecutive years, at two distinct locations of Serra da Arrábida: the more humid northern slope and the drier southern slope. A total of 1029 strains of filamentous fungi and 540 strains of yeasts were isolated, which represented at least 36 and 46 distinct species, respectively. Total counts were higher on the plants from the northern slope and there was a general increase from spring to autumn, notably on the deciduous trees for the yeasts. Plant species that had higher numbers of leaf colonists (A. monspessulanum, C. albidus, and Q. faginea) also yielded a wider range of species. Among the filamentous fungi there was a predominance of species of ascomycetous affinity, whereas basidiomycetous species dominated among yeast isolates. Some of the taxa recovered were common to other phylloplane studies (e.g., ubiquitous molds and yeasts such as Cladosporium spp. and Cryptococcus spp., respectively), but less common species were also found, some of which appeared to represent undescribed taxa. Interestingly, a few species seemed to be associated with a particular plant, notably in the case of the evergreen shrub C. albidus. However, for a considerable number of fungi and yeasts the same taxon was recovered throughout the year from more than one plant and at both sites, suggesting that such species might be genuine phylloplane inhabitants (or at least of aerial plant surfaces) even though they appeared not to display host specificity.  相似文献   

8.
To examine the colonization of living leaves from buds and twigs by phyllosphere fungi of Japanese beech, the mycobiota were investigated on buds and twigs and on leaves covered with well-ventilated bags before budbreak. Ten phyllosphere fungi were isolated from rolled-up leaves within buds, bud scales, and twigs. However, frequencies of phyllosphere fungi on expanded leaves were reduced markedly when the buds were covered with well-ventilated bags before budbreak compared to the leaves that were not covered. This observation suggests that invasion of the fungi to the leaves from buds and twigs may be possible but is not the main route. Horizontal transmission may be common in endophytes and epiphytes of beech leaves. Phyllosphere mycobiota were then compared between sun and shade leaves. Of 13 species recorded as phyllosphere fungi, the frequencies of 2 species were lower and those of 3 species were higher in sun leaves than in shade leaves. Frequencies of the other 8 phyllosphere species were not different between sun and shade leaves. This result indicates that the colonization of leaves by some phyllosphere fungi was affected by the microenvironmental conditions on leaf surfaces.  相似文献   

9.
Lowland tropical habitats harbour an unexplored genetic diversity of epiphyllous fungi. In the shade of rainforest understoreys, lichenized fungi are specialized to an ephemeral habitat where they produce little vegetative biomass and develop reproductive structures early. In a first population genetic study of epiphyllous lichen fungi, we analysed the intraspecific genetic diversity of five leaf-colonizing lichen mycobiont species. Sampling focused on a lowland perhumid forest plot in Costa Rica, with additional collections from other localities throughout the country. In all species we detected sympatric occurrence of highly diverged haplotypes. Haplotypes belonging to distinct clades in networks were also found on the same leaf, clearly indicating multiple independent colonization events on single leaves. Despite the unusually high genetic diversity of these leaf-colonizing tropical fungi, we did not detect pronounced spatial structure of the haplotype distribution between geographical regions. The observed patterns suggest that the diversity of foliicolous lichens could be much higher than expected, with several cryptic genetic lineages within each morphologically characterized species.  相似文献   

10.
The epiphytic vascular mycobiota is scarce and facultative in semi-arid Mediterranean ecosystems. However, unlike in soil conditions, little is known about the factors driving mycorrhizal communities in epiphytic environments. Here, we investigated the arbuscular mycorrhizal fungi (AMF) harboured by 31 plant species occurring on the trunks of Phoenix dactylifera. We wanted to ascertain if host identity and plant functional traits shape mycorrhizal communities. Specifically, we tested the plant life-cycle (perennial versus annual), the plant life-form (herbaceous versus woody), the plant origin (exotic versus native) and the plant species. The plant affiliation to species strongly influenced the AMF community composition. Plant life-form and plant life-cycle also shaped indicator taxa. The AMF structure differed between annual and perennial species and higher AMF richness was detected in perennial plants. The epiphytic plants associated with AMF irrespective of whether they were native or not, probably because here no functional differences derive from plant origin.  相似文献   

11.
Fungal pathogens have become a serious threat to wildlife, threatening populations of even once common, abundant species. We describe the mycobiota associated with the nasal hairs of three Molossid bat species, Cynomops planirostris, Molossus molossus, and Molossus rufus, in southwest Brazil. Bats were captured in the Cerrado and Pantanal biomes. We cultured 22 fungal isolates from twelve individual bats. Sixteen sequences of the ITS region were obtained, yielding 11 unique sequence types from the genera Aspergillus, Cladosporium, Paecilomyces, and Penicillium. No obvious detrimental effects on the bats from the fungi were observed, although some species or genera that we identified are known pathogens in other species. This is the first report of such fungi associated with the nasal hairs of Molossid bats. Our results indicate the need for further research on the biodiversity, ecological role, and potential effects of this mycobiota on Molossid bats.  相似文献   

12.
杨浩  史加勉  郑勇 《生态学报》2024,44(7):2734-2744
森林生态系统在全球碳(C)储量中占据极为重要的地位。菌根真菌广泛存在于森林生态系统中,在森林生态系统C循环过程中发挥重要的作用。阐述了不同菌根类型真菌在森林生态系统C循环过程中的功能,对比了温带/北方森林与热带/亚热带森林中菌根真菌介导的C循环研究方面新近取得的研究结果。发现温带和北方森林的外生菌根(EcM)植物对地上生物量C的贡献相对较小,然而是地下C储量的主要贡献者;以丛枝菌根(AM)共生为主的热带/亚热带森林地表生物量占比较高,表明AM植被对热带/亚热带森林地上生物量C的贡献相对较大。我们还就全球变化背景下,菌根真菌及其介导的森林生态系统C汇功能,以及不同菌根类型树种影响C循环的机制等进行了总结。菌根真菌通过影响凋落物分解、土壤有机质形成及地下根系生物量,进而影响整个森林生态系统的C循环功能。菌根介导的森林C循环过程很大程度上取决于(优势)树木的菌根类型和森林土壤中菌根真菌的群落结构。最后指出了当前研究存在的主要问题以及未来研究展望。本文旨在明确菌根真菌在森林生态系统C循环转化过程中的重要生态功能,有助于准确地评估森林生态系统C汇现状,为应对全球变化等提供重要的依据。  相似文献   

13.
Abstract:  The association between Tomicus piniperda L. (Col., Scolytinae) and fungi was studied in a Pinus sylvestris L. forest in Mielec-Mościska. Fungi were isolated from overwintered adult beetles taken from two stands situated in different distance from timber yard. Two media were used for isolation. The results showed great diversity of fungi associated with T. piniperda : 1895 cultures, representing 64 species, were isolated. Penicillia and Hormonema dematioides were the dominant species, found in 20.2% and 17.8% of all beetles, respectively. A frequently isolated ophiostomatoid fungi was Ophiostoma minus . Qualitative and quantitative differences in the mycobiota composition of this insect between two stands were detected. The highest richness and diversity of fungal species appeared in the samples taken from the location where the trees were heavily damaged by shoot-feeding of T. piniperda . Differences were most clear for the pathogenic O. minus , which was a common fungal associate of the insects in this stand.  相似文献   

14.
Three foliicolous fungi found on Tabebuia species are described and illustrated. Two are new hyphomycetous anamorphs, Passalora tabebuiae-ochraceae sp. nov. and Pseudocercospora tabebuiae-caraibae sp. nov. The third is Elsinoë tecomae, originally described on Tabebuia sp., and here epitypified based on material from Tabebuia heptaphylla. Taxonomical novelties include P. tabebuiae-ochraceae Inácio & Dianese sp. nov., P. tabebuiae-caraibae Inácio & Dianese sp. nov.  相似文献   

15.
Patterns and regulation of mycorrhizal plant and fungal diversity   总被引:20,自引:1,他引:19  
The diversity of mycorrhizal fungi does not follow patterns of plant diversity, and the type of mycorrhiza may regulate plant species diversity. For instance, coniferous forests of northern latitudes may have more than 1000 species of ectomycorrhizal (EM) fungi where only a few ectomycorrhizal plant species dominate, but there are fewer than 25 species of arbuscular mycorrhizal (AM) fungi in tropical deciduous forest in Mexico with 1000 plant species. AM and EM fungi are distributed according to biome, with AM fungi predominant in arid and semiarid biomes, and EM fungi predominant in mesic biomes. In addition, AM fungi tend to be more abundant in soils of low organic matter, perhaps explaining their predominance in moist tropical forest, and EM fungi generally occur in soils with higher surface organic matter.EM fungi are relatively selective of host plant species, while AM tend to be generalists. Similar morphotypes of AM fungi collected from different sites confer different physiological benefits to the same plant species. While the EM fungi have taxonomic diversity, the AM fungi must have physiological diversity for individual species to be so widespread, as supported by existing studies. The environmental adaptations of mycorrhizal fungi are often thought to be determined by their host plant, but we suggest that the physiology and genetics of the fungi themselves, along with their responses to the plant and the environment, regulates their diversity. We observed that one AM plant species,Artemisia tridentata, was associated with different fungal species across its range, indicating that the fungi can respond to the environment directly and must not do so indirectly via the host. Different species of fungi were also active during different times of the growing season on the same host, again suggesting a direct response to the environment.These patterns suggest that even within a single functional group of microorganisms, mycorrhizal fungi, considerable diversity exists. A number of researchers have expressed the concept of functional redundancy within functional groups of microorganisms, implying that the loss of a few species would not be detectable in ecosystem functioning. However, there may be high functional diversity of AM fungi within and across habitats, and high species diversity as well for EM fungi. If one species of mycorrhizal fungus becomes extinct in a habitat, field experimental data on AM fungi suggest there may be significant shifts in how plants acquire resources and grown in that habitat.  相似文献   

16.
Conflicts between forest management and nature protection This study gives an overview of the change of the German flora over time with special emphasis on species growing in forest habitats. As a consequence of land use plant species numbers have continually increased. Land management has also maintained some endangered plant species. The plant diversity of managed forests is higher than that of unmanaged forests. Not a single obligate forest species has gone extinct over the past 250 years of forest management, the time span of formal records. For organisms with special habitat requirements alternative protection measures other than non‐management are needed to maintain these habitats.  相似文献   

17.
Ectomycorrhizal (EcM) fungi are an important biotic factor for successful tree recruitment because they enhance plant growth and alleviate drought stress of their hosts. Thus, EcM propagules are expected to be a key factor for forest regeneration after major disturbance events such as stand-replacing forest fires. Yet the susceptibility of soil-borne EcM fungi to heat is unclear. In this study, we investigated the heat tolerance of EcM fungi of Scots pine (Pinus sylvestris L., Pinaceae). Soil samples of three soil depths were heated to the temperature of 45, 60 and 70 °C, respectively, and surviving EcM fungi were assessed by a bioassay using Scots pine as an experimental host plant. EcM species were identified by a combination of morphotyping and sequencing of the ITS region. We found that mean number of species per sample was reduced by the 60 and 70 °C treatment, but not by the 45 °C treatment. Species composition changed due to heat. While some EcM fungi species did not survive heating, the majority of species was also found in the heated samples. The most frequent species in the heat treatment were Rhizopogon roseolus, Cenococcum geophilum and several unidentified species.  相似文献   

18.
Greif MD  Gibas CF  Currah RS 《Mycologia》2006,98(5):771-780
During a survey of fungi associated with arthropods collected in a southern boreal mixed-wood forest in Alberta we obtained 29 isolates of a unique species of Leptographium. This species displayed a distinct combination of characteristics, including curved conidia on short-stipitate conidiophores, a secondary micronematous conidial state, stalked pear-shaped cells and an optimal growth rate at 35 C, and is described as Leptographium piriforme sp. nov. The isolates were most similar morphologically to L. crassivaginatum, but ITS sequence comparisons indicate that our isolates cannot be assigned to this or any other sequenced species in the genus. Initial observations on the pear-shaped cells in feeding experiments with Sancassania berlesei show that these structures may act as a nutritional incentive for visiting arthropods. Most arthropods carrying this new species were caught in traps baited with dung which, in light of its optimum growth temperature, suggests a coprophilous phase in the life cycle of this species. Additional isolates from woody species typical of the survey area might clarify whether Leptographium piriforme in its forest habitat occurs as a plant pathogen or saprobe.  相似文献   

19.
Abstract: This paper provides a revision of the foliicolous representatives of theGyalectaceae in Costa Rica. Five species of Coenogonium and 13 of Dimerella are distinguished.Coenogonium interplexum, C. interpositum, C. leprieurii, C. linkii and Dimerella vezdana are ubiquitous as to the choice of their substratum, whereas C. moniliforme and Dimerella lutea are facultatively foliicolous. The remainder are typically foliicolous taxa but may occasionally be found on bark. The following species are for the first time reported as foliicolous from Costa Rica: Coenogonium interplexum, C. interpositum, C. leprieurii, C. moniliforme, Dimerella fallaciosa, D. lisowskii , and D. aff. pilifera . Three new species are described: Dimerella isidiifera sp. nov. with disciform isidia, D. subzonata sp. nov. with small, bright yellow, dentate apothecia and a whitish prothallus, and D. siquirrensis sp. nov. with large, orange apothecia and a thin whitish prothallus. A key is presented for neotropical foliicolous Gyalectaceae , and notes on the distribution and ecology of the species are given.  相似文献   

20.
Fungi in the basidiomycete order Corticiales are remarkably diverse nutritionally, including a variety of saprotrophs, plant and fungal pathogens, and lichen-forming fungi. Tracing the origin of this diversity depends on a clearer understanding of the phylogenetic relationships of fungi in the order. One of its core members is the genus Marchandiomyces, originally established for lichen pathogens that form orange or coral bulbils. We describe here a new species in the genus, M. marsonii sp. nov., which is unusual in its appearance, habit, and geographic provenance. It is foliicolous on leaves of Pandanus (screw pines, Pandanaceae) and produces flattened, coral bulbils resembling apothecia of the ascomycete genus Orbilia. It is also the first member of the genus to be collected from Australia. An isolate of the new fungus and several additional cultures of related plant pathogenic fungi were obtained and investigated phylogenetically using parsimony, likelihood, and Bayesian analyses of nuclear small and large subunit ribosomal sequences. Our phylogeny makes clear that Marchandiomyces species and their close relatives contribute significantly to the ecological diversity of the Corticiales and that this diversity is derived mainly from lignicolous ancestors.  相似文献   

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