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1.
Ectomycorrhizal (ECM) fungi have a worldwide distribution. However, the ecology of tropical ECM fungi is poorly documented, limiting our understanding of the symbiotic associations between tropical plants and fungi. ECM Basidiomycete diversity was investigated for the first time in two tropical rain forests in Africa (Western Upper Guinea) and in Asia (Western Ghats, India), using a fragment of the mitochondrial large subunit rRNA gene to type 140 sporocarps and 54 ectomycorrhizas. To evaluate taxonomic diversity, phylogenetic analyses were performed, and 40 sequences included from identified European specimens were used as taxonomic benchmarks. Five clades were recovered corresponding to six taxonomic groups: boletoids, sclerodermatoids, russuloids, thelephoroids, and a clade grouping the Amanitaceae and Tricholomataceae families. Our results revealed that the Russulaceae species display a great diversity with several putative new species, especially in Guinea. Other taxonomic issues at family/section levels are also briefly discussed. This study provides preliminary insights into taxonomic diversity, ECM status, and biogeographic patterns of ECM fungi in tropical two rain forest ecosystems, which appear to be as diverse as in temperate and boreal forests.  相似文献   

2.
The diets of small mammals in different hemiboreal spruce-dominated, oak-dominated and mixed forests in western part of Lithuania were studied by examination of fungal spores in fresh fecal pellets of caught animals. In the diets of mice (Apodemus spp.), bank voles (Myodes glareolus), and common and pygmy shrews (Sorex araneus and S. minutus), 22 different fungal taxa were identified, 15 of which were hypogeous fungi. The sporocarp abundance and the spores in fecal samples of Elaphomyces fungi prevailed in study area during this investigation. Although most of the captured individuals consumed fungi, the consumption varied among small mammal species. The data show that the fungi were more frequent and taxonomically diverse in Myodes glareolus than in Apodemus spp. diets. The study provided evidence that the fungal component in the diets of insectivorous Sorex species is more diverse than previously known. The availability of sporocarps and the fungal component in the diets of small mammals showed seasonal effects. Annual hypogeous and epigeous sporocarp abundances did not vary significantly across forest types. The significant difference in mycophagy was observed across all forest cover types, with the greatest fungal diversity in fecal samples collected in mixed coniferous-deciduous tree stands.  相似文献   

3.
Ectomycorrhizal (ECM) hyphal communities have not been well characterized. Furthermore, there have been few studies where the ECM hyphal community is compared to fungi detected as sporocarps or ECM-colonized root tips. We investigated fungi present as hyphae in a well-studied California Quercus–Pinus woodland. Hyphal species present were compared to those found as sporocarps and ECM root tips at the same site. Hyphae were extracted from root-restrictive nylon mesh in-growth bags buried in the soil near mature Quercus douglasii, Quercus wislizeni, and Pinus sabiniana. Taxa were identified using PCR, cloning, and DNA sequencing of internal transcribed spacer and 28s rDNA. Among the 33 species detected, rhizomorph-forming ECM fungi dominated the hyphal community, especially species of Thelephoraceae and Boletales. Most fungi in soils near Quercus spp. and P. sabiniana were ECM basidiomycetes, but we detected two ECM ascomycetes and three non-mycorrhizal fungi. Many ECM species present as hyphae were also previously detected at this site as sporocarps (18%) or on ECM root tips (58%). However, the hyphal community was mostly dominated by different taxa than either the sporocarp or ECM root communities.  相似文献   

4.
This investigation sought to examine if there was a difference between the ectomycorrhizal (ECM) communities in plots of native oak and introduced Scots pine and Sitka spruce forest. The ECM communities in four plots of each forest type were described, from five soil cores collected in each plot, by morphotyping, internal transcribed spacer (ITS)-restriction fragment length polymorphism matching of mycorrhizas and sporocarps and ITS sequencing. Fifty-one distinct taxa were distinguished; 25 were identified to species level, 11 to genus and 15 remained unidentified. Seventy-one ECM species were recorded as sporocarps from the forest plots; most (43 species) were found in the Sitka spruce plots. The below-ground ECM communities of the different forest types did not differ significantly with respect to species richness of taxa on roots, but differed in species composition. Multivariate analysis produced a clear separation of the communities of the different forest types using below-ground data, but the above-ground sporocarp data did not separate the forest types. Moreover, results of a Mantel test found no relationship between the above- and below-ground similarity matrices. The oak plots had the most distinctive ECM community, with Laccaria amethystina and Elaphomyces granulatus being frequent. The Sitka spruce plots showed the lowest intra-forest type similarity and were often dominated by "nursery type" ectomycorrhizas. There was only 10% similarity between the above- and below-ground ECM species in these plots, different colonisation methods of ectomycorrhizal taxa and insufficient below-ground sampling being possible reasons for this disparity. Our results indicate that plantations of non-native Sitka spruce can support similar levels of ECM diversity as native forests.  相似文献   

5.
Sporocarps (fruit bodies) are the sexual reproductive stage in the life cycle of many fungi. They are highly nutritious and consequently vulnerable to grazing by birds and small mammals, and invertebrates, and can be infected by microbial and fungal parasites and pathogens. The complexity of communities thriving inside sporocarps is largely unknown. In this study, we revealed the diversity, taxonomic composition and host preference of fungicolous fungi (i.e., fungi that feed on other fungi) in sporocarps. We carried out DNA metabarcoding of the ITS2 region from 176 sporocarps of 11 wood-decay fungal host species, all collected within a forest in northeast Finland. We assessed the influence of sporocarp traits, such as lifespan, morphology and size, on the fungicolous fungal community. The level of colonisation by fungicolous fungi, measured as the proportion of non-host ITS2 reads, varied between 2.8–39.8% across the 11 host species and was largely dominated by Ascomycota. Host species was the major determinant of the community composition and diversity of fungicolous fungi, suggesting that host adaptation is important for many fungicolous fungi. Furthermore, the alpha diversity was consistently higher in short-lived and resupinate sporocarps compared to long-lived and pileate ones, perhaps due to a more hostile environment for fungal growth in the latter too. The fungicolous fungi represented numerous lineages in the fungal tree of life, among which a significant portion was poorly represented with reference sequences in databases.Subject terms: Microbial ecology, Molecular evolution  相似文献   

6.
Mycorrhizal fungi that form hypogeous sporocarps are an important component of the temperate forest soil community. In many regions, such as the Nothofagus forest in the Patagonian Andes, this group of fungi has been poorly studied. Here we examined the spring and autumn community composition of "sequestrate fungi", based on sporocarp production in pure forests of Nothofagus dombeyi (evergreen) and N. pumilio (deciduous). We investigated the possible relationships between these communities and environmental factors over 2 y. The rarefaction curves and the minimal richness estimates converged at nearly the same level for each forest type, and the asymptotes suggested that the sampling effort was sufficient to capture most of the hypogeous sporocarp richness in these forest stands. In total 27 species were recovered. Basidiomycota, Ascomycota and Glomeromycota respectively accounted for nine, two and one genera. Species richness of hypogeous sporocarps varied in relation to forest type but not to season (fall and spring), whereas sporocarp biomass varied according to an interaction between season and forest type. Species richness and sporocarp biomass were positively correlated with rainfall and negatively correlated with altitude. In addition sporocarp species richness was positively related to number of trees per transect. We found that two different forest stands, each dominated by different species of Nothofagus, exhibited different hypogeous sporocarp communities.  相似文献   

7.
The genera Dicymbe and Aldina (Fabaceae) host ectomycorrhizal fungi (EcM) and are common in white sand forests (WSFs), a highly specialized habitat with a high level of plant endemism compared with terra-firme forests. In this study, we visited four times a 1-ha permanent plot established in a small patch of a WSF in the south of Colombia Amazonia. Forty-eight species of EcM fungi were recovered from sporocarps and 15 ITS species-level were detected from root tips. Seventeen species were new reports to Colombia and seven corresponded to undescribed species. These results confirm that this WSF supports a significant EcM fungal diversity. Most of the species found in this study have been previously reported to be associated with other legume and/or dipterocarp species from geographically distant forests. The long-distance occurrence combined with low host specificity, suggest the possibility of gene flow between geographically distant populations of EcM fungi in neotropical lowland rainforests.  相似文献   

8.
  1. Although it is well known that nitrogen (N) additions strongly affect ectomycorrhizal (EM) fungal community composition, less is known about how different N application rates and duration of N additions affect the functional role EM fungi play in the forest N cycle.
  2. We measured EM sporocarp abundance and species richness as well as determined the δ15N in EM sporocarps and tree foliage in two Pinus sylvestris forests characterized by short- and long-term N addition histories and multiple N addition treatments. After 20 and 39 years of N additions, two of the long-term N addition treatments were terminated, thereby providing a unique opportunity to examine the temporal recovery of EM sporocarps after cessation of high N loading.
  3. In general, increasing N availability significantly reduced EM sporocarp production, species richness, and the amount of N retained in EM sporocarps. However, these general responses were strongly dependent on the application rate and duration of N additions. The annual addition of 20 kg·N·ha−1 for the past 6 years resulted in a slight increase in the production and retention of N in EM sporocarps, whereas the addition of 100 kg·N·ha−1·yr−1 during the same period nearly eliminated EM sporocarps. In contrast, long-term additions of N at rates of ca. 35 or 70 kg·N·ha−1·yr−1 for the past 40 years did not eliminate tree carbon allocation to EM sporocarps, although there was a decrease in the abundance and a shift in the dominant EM sporocarp taxa. Despite no immediate recovery, EM sporocarp abundance and species richness approached those of the control 20 years after terminating N additions in the most heavily fertilized treatment, suggesting a recovery of carbon allocation to EM sporocarps after cessation of high N loading.
  4. Our results provide evidence for a tight coupling between tree carbon allocation to and N retention in EM sporocarps and moreover highlight the potential use of δ15N in EM sporocarps as a relative index of EM fungal sink strength for N. However, nitrogen additions at high dosage rates or over long time periods appear to disrupt this feedback, which could have important ramifications on carbon and nitrogen dynamics in these forested ecosystems.
  相似文献   

9.
晚生型外生菌根真菌通常出现在森林演替的后期,是成熟林中的优势外生菌根真菌类群.对四川都江堰一片亚热带针阔混交林中的菌根真菌地上群落进行调查,并应用二元逻辑回归分析对晚生型外生菌根真菌的主要类群,即鹅膏菌科、牛肝菌科和红菇科,与周围(5 m×5 m样方)树种组成的关系进行研究.还应用次级变量分析方法对主要外生菌根真菌类群的空间格局进行了分析.结果表明,非外生菌根树种及某些外生菌根树种对特定类群菌根真菌子实体的出现有抑制作用,而不同类群外生菌根真菌在克隆生长上的差异并不是子实体空间分布的决定因素.我们认为,当研究自然林中外生菌根子实体的空间分布时,除了宿主植物的分布,也应考虑非宿主植物的分布以及菌根真菌相互作用的影响.  相似文献   

10.
晚生型外生菌根真菌通常出现在森林演替的后期,是成熟林中的优势外生菌根真菌类群。对四川都江堰一片亚热带针阔混交林中的菌根真菌地上群落进行调查,并应用二元逻辑回归分析对晚生型外生菌根真菌的主要类群,即鹅膏菌科、牛肝菌科和红菇科,与周围(5m×5m样方)树种组成的关系进行研究。还应用次级变量分析方法对主要外生菌根真菌类群的空间格局进行了分析。结果表明,非外生菌根树种及某些外生菌根树种对特定类群菌根真菌子实体的出现有抑制作用,而不同类群外生菌根真菌在克隆生长上的差异并不是子实体空间分布的决定因素。我们认为,当研究自然林中外生菌根子实体的空间分布时,除了宿主植物的分布,也应考虑非宿主植物的分布以及菌根真菌相互作用的影响。  相似文献   

11.
Liang Y  Guo LD  Ma KP 《Mycorrhiza》2005,15(2):137-142
The population genetic structure of the late-stage fungus Amanita manginiana in a natural forest in Dujiangyan, southwest China was examined over two years using inter-simple sequence repeat (ISSR) markers. Seven ISSR primers were used and 170 bands were obtained in this population: 134/160 and 135/153 bands were polymorphic for sporocarps of 2001 and 2002, respectively. Each sporocarp represented a single genet in 2001 and 2002, and no identical genets were found between the two years. The results of genetic similarity comparison, using unweighted pair group method with arithmetic means, and analysis of molecular variance, indicated that although genetic variances were mainly within individuals of the same year the genetic variance between years was statistically significant (P<0.001). Relationships between genetic similarity and spatial distance of pairwise sporocarps were also found to be different in the two years. The differences in genetic structure and genetic similarity between individuals of the two years implied that the sporocarps were not likely to be derived from continuous generations, i.e., the sporocarps collected in 2002 were not developed from sexual spores dispersed by sporocarps of 2001. We suggest that the life-cycle traits of ectomycorrhizal (ECM) fungi should be considered in genetic studies on ECM fungal populations.  相似文献   

12.
An investigation was undertaken to assess the community structure of ectomycorrhizal (ECM) fungi on naturally regenerating European larch (Larix decidua Mill.) seedlings grown under forest conditions. The sites examined were in two managed monoculture larch forests, differentiated by soil chemistry and mature tree density. Morphological and molecular analyses revealed a total of 22 fungal taxa. From detected ECM fungal taxa, 13 were noted at Site I and 13 at Site II. Only four taxa were found in both sites (Russula ochroleuca, Thelephora terrestris, Lactarius tabidus and Paxillus involutus). The most abundant species at Site I (lower mineral concentration, high tree density) was Hydnotrya tulasnei (25.7?%), followed by Pseudotomentella tristis, Tomentella sublilacina and Russula puelaris. At Site II (higher mineral concentration, low tree density) the dominant fungal symbiont of larch seedlings was clearly Wilcoxina mikolae, which accounted for 74?% of mycorrhizal tips. The less abundant species comprised T. terrestris, L. tabidus, Xerocomus pruinatus and R. ochroleuca. The analysis of similarity (ANOSIM) and non-metric multidimensional scaling (NMDS) ordination clearly separated the ECM fungal assemblages in the two sites tested. Because our study sites were differentiated by many factors, it is not easy to distinguish one factor in particular to explain the differences observed between the ECM communities at Sites I and II. The results obtained significantly increase our knowledge about the diversity of the ECM fungi hosted by L. decidua. The large number of ECM fungi detected was the first observation showing these fungi as symbiotic partners of European larch.  相似文献   

13.
Aim Current evidence from temperate studies suggests that ectomycorrhizal (ECM) fungi require overland routes for migration because of their obligate symbiotic associations with woody plants. Despite their key roles in arctic ecosystems, the phylogenetic diversity and phylogeography of arctic ECM fungi remains little known. Here we assess the phylogenetic diversity of ECM communities in an isolated, formerly glaciated, high arctic archipelago, and provide explanations for their phylogeographic origins. Location Svalbard. Methods We generated and analysed internal transcribed spacer (ITS) nuclear ribosomal DNA sequences from both curated sporocarp collections (from Svalbard) and soil polymerase chain reaction (PCR) clone libraries (from Svalbard and the North American Arctic), compared these with publicly available sequences in GenBank, and estimated the phylogenetic diversity of ECM fungi in Svalbard. In addition, we conducted coalescent analyses to estimate migration rates in selected species. Results Despite Svalbard’s geographic isolation and arctic climate, its ECM fungi are surprisingly diverse, with at least 72 non‐singleton operational taxonomic units (soil) and 109 phylogroups (soil + sporocarp). The most species‐rich genera are Thelephora/Tomentella, Cortinarius and Inocybe, followed by Hebeloma, Russula, Lactarius, Entoloma, Sebacina, Clavulina, Laccaria, Leccinum and Alnicola. Despite the scarcity of available reference data from other arctic regions, the majority of the phylogroups (73.4%) were also found outside Svalbard. At the same time, all putative Svalbard ‘endemics’ were newly sequenced taxa from diverse genera with massive undocumented diversity. Overall, our results support long‐distance dispersal more strongly than vicariance and glacial survival. However, because of the high variation in nucleotide substitution rates among fungi, allopatric persistence since the Pliocene, although unlikely, cannot be statistically rejected. Results from the coalescent analyses suggest recent gene flow among different arctic areas. Main conclusions Our results indicate numerous recent colonization events and suggest that long‐distance, transoceanic dispersal is widespread in arctic ECM fungi, which differs markedly from the currently prevailing view on the dispersal capabilities of ECM fungi. Our molecular evidence indicates that long‐distance dispersal has probably played a major role in the phylogeographic history of some ECM fungi in the Northern Hemisphere. Our results may have implications for studies on the biodiversity, ecology and conservation of arctic fungi in general.  相似文献   

14.
Summary Sporocarps and sclerotia were collected for a one-year period in 23- and 180-year-old Abies amabilis stands in western Washington. All sporocarps were classified and chemically analyzed for N, P, K, Ca, Mg, Na and Fe. Lactarius sp. and Cortinarius sp. contributed the largest proportion of the total annual epigeous sporocarp production in both stands. Annual epigeous production was 34 kg/ha in the young stand and 27 kg/ha in the mature stand. Hypogeous sporocarp production increased from 1 kg ha-1 yr-1 to 380 kg ha-1 yr-1 with increasing stand age. High sclerotia biomass occurred in the young (2,300 kg/ha) and mature (3,000 kg/ha) stands. Peak sclerotia and epigeous sporocarp biomass in the young stand and epigeous and hypogeous sporocarp biomass in the mature stand coincided with the fall peak of mycorrhizal root biomass.In the young stand, sporocarps produced by decomposer fungi concentrated higher levels of Ca and Mn than those produced by mycorrhizal fungi. In the mature stand, sporocarps of decomposer fungi concentrated higher levels of N, P, Mn, Ca and Fe than sporocarps of mycorrhizal fungi. Epigeous and hypogeous sporocarps concentrated higher levels of N, P, and K than sclerotia or mycelium. The highest concentration of N (4.36%), P (0.76%), K (3.22%) and Na (1,678 ppm) occurred in epigeous sporocarps. Highest Mn (740 ppm) and Ca (20,600 ppm) concentrations occurred in mycelium, while highest Mg (1,929 ppm) concentrations were in hypogeous sporocarps and highest Fe (4,153 ppm) concentrations were in sclerotia.  相似文献   

15.
S. D. Ghate 《Plant biosystems》2016,150(5):977-986
Forty-six species of macrofungi (27 genera) were recorded in 25 quadrats (625 m2) in five mangroves of the southwest India (Paduhithlu, Nadikudru, Sasihithlu, Thokottu and Batapady). A maximum of 20 species occurred in Sasihithlu with a highest diversity value. Four species belong to coregroup ( ≥ 10 sporocarps/quadrat), while 29 species were confined to specific mangrove (exclusive species). Out of 1591 sporocarps, Paduhithlu supported the highest number of sporocarps (564) followed by Nadikudru (502). Rarefaction curves showed a steep increase in the expected number of species against the number of sporocarps in Sasihithlu. Pearson correlation between biotic factors (species richness, sporocarp richness and species diversity) and edaphic factors (air and soil) was not significantly correlated. Woody litter supported the highest number of macrofungi (26 species) followed by soil (22 species) and least in leaf litter (7 species). Up to one-third of macrofungi recovered in mangroves are economically valuable (edible, medicinal and ectomycorrhizal).  相似文献   

16.
Endogone corticioides sp. nov. was described from subalpine conifer forests in Japan and China. This species is similar to E. pisiformis in its yellowish sporocarps and zygosporangia on the equal empty gametangia. Endogone corticioides was clearly distinguished from E. pisiformis based on its resupinate sporocarp, the presence of hyphal peg-like structures on the peridium, and abundant thick-walled hyphae in the gleba. Phylogenetic analysis of the small and large subunit nuclear ribosomal RNA and the elongation factor-1α genes suggested that E. corticioides is closely related to E. pisiformis. Limited vegetative growth from the surface-sterilized sporocarps on agar media was shown.  相似文献   

17.
18.
Ectomycorrhizal (ECM) communities were assessed on a 720 m2 plot along a chronosequence of red oak (Quercus rubra) stands on a forest reclamation site with disturbed soil in the lignite mining area of Lower Lusatia (Brandenburg, Germany). Adjacent to the mining area, a red oak reference stand with undisturbed soil was investigated reflecting mycorrhiza diversity of the intact landscape. Aboveground, sporocarp surveys were carried out during the fruiting season in a 2-week interval in the years 2002 and 2003. Belowground, ECM morphotypes were identified by comparing sequences of the internal transcribed spacer regions from nuclear rDNA with sequences from the GenBank database. Fifteen ECM fungal species were identified as sporocarps and 61 belowground as determined by morphological/anatomical and molecular analysis of their ectomycorrhizas. The number of ECM morphotypes increased with stand age along the chronosequence. However, the number of morphotypes was lower in stands with disturbed soil than with undisturbed soil. All stands showed site-specific ECM communities with low similarity between the chronosequence stands. The dominant ECM species in nearly all stands was Cenococcum geophilum, which reached an abundance approaching 80% in the 21-year-old chronosequence stand. Colonization rate of red oak was high (>95%) at all stands besides the youngest chronosequence stand where colonization rate was only 15%. This supports our idea that artificial inoculation with site-adapted mycorrhizal fungi would enhance colonization rate of red oak and thus plant growth and survival in the first years after outplanting.  相似文献   

19.
This study was conducted to evaluate the effects of wildfires on ectomycorrhizal (EM) fungal communities in Scots pine ( Pinus sylvestris ) stands. Below- and above-ground communities were analysed in terms of species richness and evenness by examining mycorrhizas and sporocarps in a chronosequence of burned stands in comparison with adjacent unburned late-successional stands. The internal transcribed spacer (ITS)-region (rDNA) of mycobionts from single mycorrhizas was digested with three restriction enzymes and compared with an ITS–restriction fragment length polymorphism (RFLP) reference database of EM sporocarps. Spatial variation seemed to be more prominent than the effects of fire on the EM fungal species composition. Most of the common species tended to be found in all sites, suggesting that EM fungal communities show a high degree of continuity following low-intensity wildfires. Species richness was not affected by fire, whereas the evenness of species distributions of mycorrhizas was lower in the burned stands. The diversity of EM fungi was relatively high considering that there were only three EM tree species present in the stands. In total, 135 EM taxa were identified on the basis of their RFLP patterns; 66 species were recorded as sporocarps, but only 11 of these were also recorded as mycorrhizas. The species composition of the below-ground community of EM fungi did not reflect that of the sporocarps produced. EM fungal species present in our ITS–RFLP reference database accounted for 54–99% of the total sporocarp production in the stands, but only 0–32% of the mycorrhizal abundance.  相似文献   

20.
The beetle fauna of 299 sporocarps of the bracket fungus Fomitopsis pinicola in a 200 ha spruce forest in southeastern Norway was investigated in relation to sporocarp, tree and forest variables. The sporocarps contained 36 species of beetles, of which six species are on the Norwegian Red List. Of 12,373 individual beetles collected, 91% were Cis glabratus. Plots of species accumulation curves suggested that there may be more than 60 beetle species present in F. pinicola in the area, but that probably all the specialist Ciidae were found. The major factor influencing beetle diversity turned out to be the level of dead wood at and in the vicinity of the sampling site, with a higher number of species per unit volume of sporocarps in areas with high levels of dead wood. There were also significantly more red-listed species in those areas. Analysing the species occurrence with stepwise logistic regression, we show preferential habitat selection of the six most abundant species of Ciidae. Conservation of beetles associated with bracket fungi using amount of dead wood as a surrogate measurement is discussed.  相似文献   

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