No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Molecular and morphological diversity of pezizalean ectomycorrhiza
Abstract
A growing body of molecular research is discovering a high diversity of pezizalean ectomycorrhiza (EcM), yet most remain unidentified at the genus or species level. This study describes EcM-forming taxa within the Pezizales. EcM-forming Pezizales were revealed by morphotyping and sequencing of EcM root tips from forests in Estonia and Denmark. The taxa on EcM root tips were identified using phylogenetic analyses of large-subunit rDNA sequences derived from sporocarps of 301 pezizalean species, and comparisons with internal transcribed spacer rDNA sequences. Thirty-three species are suggested as EcM symbionts, representing all three major clades of Pezizales, the genera Genea, Geopora, Humaria, Tarzetta, Trichophaea, Wilcoxina, Helvella, Hydnotrya, Tuber, Pachyphloeus, Peziza and Sarcosphaera, and two Pezizaceae anamorphs. EcM of Pezizales species are easily distinguished by their anatomy, particularly thick cell walls and stout hyphae. This study demonstrates that Pezizales species constitute a considerable proportion of the mycobionts in EcM fungal communities in mature boreal deciduous and coniferous forests, in several soil types. Fruit-body sequences and EcM descriptions will facilitate identification of pezizalean EcM in future studies.
... (Shameem et al. 2016). They are also important as ectomycorrhizal symbionts (Tedersoo et al. 2006, Hwang et al. 2015. ...
... With the development of molecular phylogenetics, the taxonomy of Helvella has been re-evaluated. Sequences of nuclear large and small subunit ribosomal DNA (LSU and SSU) were adopted for phylogenetic inference of Helvella sensu lato and its allied genera (Hansen and Pfister 2006, Tedersoo et al. 2006, Laessoe and Hansen 2007. Protein-coding genes, RNA polymerase II the largest subunit (RPB1), the second largest subunit (RPB2) and translation elongation factor 1-α (TEF1) were also applied . ...
... ITS is recommended as the universal barcode for fungi (Schoch et al. 2012), which is applied widely to elucidate species diversity of the pezizalean ectomycorrhizae (Tedersoo et al. 2006, Hwang et al. 2015. However, very limited ITS sequences of cupulate Helvella species were available in GenBank. ...
Helvella species are ascomycetous macrofungi with saddle-shaped or cupulate apothecia. They are distributed worldwide and play an important ecological role as ectomycorrhizal symbionts. A recent multi-locus phylogenetic study of the genus suggested that the cupulate group of Helvella was in need of comprehensive revision. In this study, all the specimens of cupulate Helvella sensu lato with ribbed stipes deposited in HMAS were examined morphologically and molecularly. A four-locus phylogeny was reconstructed using partial sequences of the heat shock protein 90, nuclear rDNA internal transcribed spacer region 2, nuclear large subunit ribosomal DNA and translation elongation factor 1-α genes. Three clades were revealed in Helvella sensu stricto. Twenty species were included in the analysis, of which 13 are distributed in China. Three new species, H. acetabuloides, H. sichuanensis and H. tianshanensis, are described and illustrated in detail. A neotype was designated for H. taiyuanensis. Helvella calycina is a new record for China, while Dissingia leucomelaena should be excluded from Chinese mycota. Hsp90 and ITS2 are recommended as useful supplementary barcodes for species identifications of the genus.
... The genus Hydnotrya (Pezizales, Discinaceae) comprises ascomycetes with hypogeous sporocarps (Montecchi and Sarasini 2000), which are suspected to be ectomycorrhizal (Newton and Haigh 1998, Tedersoo et al. 2006). However, the mycorrhizal status and host plant preferences of Hydnotrya tulasnei Berk. & Br. are still unclear. Tedersoo et al. (2006) molecularly detected H. tulasnei in root samples from a mixed forest (Picea abies, Tilia cordata, Betula pendula, Populus tremula) in Estonia and described a putative H. tulasnei morphotype. However, the authors detected neither the exact host species (except beech at two localities in Denmark) nor isolated H. tulasnei into a pure cultu ...
... B48 " (= GenBank AJ534700 = H. tulasnei, Tedersoo et al. 2006). Thus, genotype analysis confirmed that HTU-1, isolated from the morphologically identified H. tulasnei sporocarp belonged to this species and both genotype and phenotype analyses confirmed that MVA-1 and MVA-2 represented different strains of M. variabilis. ...
... Une partie des espèces (celles affines à P. succosa) ont des asques dépourvus de crochets, un caractère assez peu fréquent chez les Pezizaceae (JAkLITsCH et al., 2016). en outre, toutes les espèces connues sont mycorhiziques (TeDeRsOO et al., 2006 ;TeDeRsOO et al., 2010 ;sMITH, 2014 ; VAN VOOReN, 2022). Depuis la publication de ce genre, plusieurs espèces ont été publiées comme nouvelles ou réhabilitées ( VAN VOO-ReN & MOYNe, 2021 ; VAN VOOReN, 2022). ...
... en absence de suc, l'examen microscopique permettra de les séparer, P. badiofusca possédant des ascospores en moyenne plus larges, soit un ratio Q plus faible que celui de P. michelii, 1,6 vs. 1,9, d'après nos données personnelles. espèce mycorhizique, elle semble s'associer à différentes essences de feuillus, peut-être préférentiellement avec les Betulaceae (Alnus spp., Betula spp.) d'après la littérature consultée (TeDeRsOO et al., 2006 ;TeDeRsOO et al., 2008 ;AsHRAF et al., 2012). ...
les espèces violettes du genre Paragalactinia, P. michelii et P. berthetiana, sont présentées en détail et illustrées à partir de nombreuses récoltes. Une phylogénie basée sur des séquences ITs centrée sur ce genre est également proposée et commentée. enfin, une clé des Paragalactinia connus en europe est four-nie. Mots-clés : Ascomycota, Pezizales, phylogénie, taxinomie. Overview of violet Peziza (Pezizaceae) present in Europe. 4 th part: the genus Paragalactinia Abstract: The violet species of the genus Paragalactinia, P. michelii and P. berthetiana, are presented in detail and illustrated from numerous collections. A phylogeny based on ITs sequences focused on this genus is also proposed and commented. Finally, a key to the european known Paragalactinia is provided.
... Yin et al., 2017). It has been established that ECM fungi play a key role in forest ecosystem functioning (Tedersoo et al., 2006). They could receive carbon from their host plant in exchange for providing multiple benefits such as access to nutrients and water (Kjøller et al., 2012;Li et al., 2015). ...
... More importantly, changes in soil pH affect ECM fungi not only their growth and reproduction (Dennis, 1985;Petersen, 1985), but also the frequency, abundance, and diversity of Pezizales at the community level, ultimately induce shifts in the ECM community (M. E. Smith et al., 2007;Tedersoo et al., 2006). There is a positive correlation between the relative abundance of Helvellosebacina and soil pH in our result ( Likewise, nitrogen addition and water regimes would also affect SAP, and further contribute to ECM community shifts. ...
Background
Ectomycorrhizal (ECM) symbiosis is a fundamental driver in forest ecosystems. Studies of effects of fertilizer treatment on ECM fungal community structure were predominantly based on large, single additions of nitrogen. Studies involving chronic additions of nitrogen in combination with different gradients of water regime are much less common.
Aim
To investigate effects of water regime and nitrogen addition on the structure and diversity of ECM community, and identify main factors leading to changes in ECM community of Picea asperata.
Methods
The structure and diversity of the ECM community were assessed by Illumina high throughput sequencing analysis of the internal transcribed spacer (ITS) region of rDNA extracted from ECM root tips, after 5 years of different gradients of water regimes [40% (W1), 50% (W2), 60% (W3), 80% (W4) and 100% (W5) of field capacity, respectively] and nitrogen additions [0 (N0), 20 (N1), 40 (N2) g N m–2 y–1 by adding ammonium nitrate (NH4NO3) solution].
Results
ECM community structure was altered by water and nitrogen treatments. Clearer separations were found under water treatment than under nitrogen treatment. ECM community species richness of N1 was significantly higher than that of N2 under W5 treatment and was significantly influenced by the interaction of water and nitrogen. However, the diversity and evenness of the ECM community were unaffected. Soil water content (SWC), nitrogen availability and their interaction, soil available phosphorus, and pH (which were induced by treatments) significantly explained the variation in ECM community structure among different treatments.
Conclusion
ECM species are more sensitive to changes in SWC than changes in nitrogen addition. Nitrogen and water treatments influenced the structure of the ECM community mainly through altering the relative abundances of exploration types and specific genera. Our findings can enhance understanding of the implications of nitrogen addition and water regime on soil processes in ECM-dominated coniferous forests under global changes.
... (Smith et al. 2006), Picea abies (L.) Karst. (Tedersoo et al. 2006), Epipactis atrorubens (Hoffm.) Besser. ...
... Fujimura et al. (2005) have reported G. cooperi form mycorrhiza with Pinus ponderosa. Tedersoo et al. (2006) have identified ectomycorrhizal Geopora spp. on root tips both in coniferous and deciduous woodlands. They also have found Geopora spp. ...
The Pezizales are an order of the subphylum Pezizomycotina within the phylum Ascomycota. Members of this order are characterized by unitunicate asci that typically open by rupturing to form a terminal or eccentric lid or operculum (Hansen & Pfister 2006). Of the 1638 Pezizales species known so far, Geopora Harkn. (Pyronemataceae) is represented by 23 species (Kirk et al. 2008). Geopora spp. are characterized by entirely or partially hypogeous, globular, semi-globular or cup-shaped ascocarps, whitish, greyish or yellowish grey hymenium, cylindrical, 8-spored and operculate asci, generally bifurcate, septate and hyaline paraphyses, ellipsoid, smooth ascospores mostly with one or two larger oil drops and some smaller oil drops (Tamm et al.
... Some species of Geopora occur infrequently and be difficult to collect because they depend on moisture for sporulation and are hypogeous at some developmental stage (Flores-Rentería et al. 2014, Saba et al. 2019. The mycorrhizal association of Geopora species with various conifers and deciduous trees such as Pinus ponderosa (Fujimura et al. 2005), Pinus edulis (Gordon & Gehring 2011, Flores-Rentería et al. 2014, Cercocarpus ledifolius (Southworth & Frank 2017), Salix linearistipularis (Ishida et al. 2009) Juniperus excelsa (Kajevska et al. 2013), Quercus garryana (Frank et al. 2009), Quercus douglasii (Smith et al. 2007) Picea abies (Tedersoo et al. 2006), Pseudotsuga menziesii, Abies concolor (Fogel & Pacioni 1989), Epipactis atrorubens (Shefferson et al. 2008), Abies grandis, Cedrus spp., and Populus spp. (Tamm et al. 2010) have been confirmed by molecular techniques. ...
... The most or all Geopora species form ectomycorrhizal (Tedersoo et al. 2006). In this study we isolated the H. ledifolium roots directly from under zone of G. ramila, but we have not yet confirmed the ectomycorrhizal status of G. ramila based on sequences on ectomycorrhizal root tips. ...
A new Geopora species (Pyronemataceae), Geopora ramila was described and illustrated from the soil, under or in the vicinity of Helianthemum ledifolium var. ledifolium annual plant in Fars province, Iran. Morphologically, G. ramila is similar to G. pinyonensis and G. arenicola but distinguished from both by a combination of morphological characters including, color and size of ascocarps, size and shape of ascospores, habit and associated host. The ribosomal DNA internally transcribed spacer (rDNA ITS) sequence of the new species (Acc. No. MT108930 to MT108934) showed 87.82% identity with G. pinyonensis in the BLAST search in GenBank. ITS-based phylogenetic analysis clearly supports G. ramila is a new and distinctive species lacking close relatives among described species of Geopora.
... To test whether functional groups of sporocarps will differ in the high-severity burn patches compared to moderate-severity or unburned areas, we separated species into different functional groups (either EM or saprotrophic) based on common consensus from past studies (e.g. Tedersoo et al., 2006;Tedersoo and Smith, 2013) or by isotopic analysis. Most species were determined from the literature; however, eleven species were analyzed for stable isotope content. ...
... Species found in later-successional stands can colonize multiple hosts with established common mycorrhizal networks (CMNs) Beiler et al., 2010). Long distance EM exploration types can connect with other mycelia to form CMNs for nutrient transfer, yet they require more carbon than short distance types (Agerer, 2001;2006, Tedersoo andSmith, 2013). Evidence suggests that short-distance EM exploration types dominate in dry-forest pine seedlings, because we found a much higher relative abundance of this type in all ponderosa pine seedlings compared to medium-or long-distance exploration types, similar to the findings of for Pinus edulis seedlings. ...
... Increase in Pezizales in the NPK + PigManure treatment was not as a result of direct input from the pig manure but was induced by long-term addition of pig manure, since Pezizales in the pig manure only accounted for 0.45% of the total sequences (data not shown). Pezizales become more abundant and diverse with increase in pH in forest soils (Tedersoo et al., 2006;Kluber et al., 2012;Tedersoo et al., 2014;Ge et al., 2017). Kjøller and Clemmensen (2009) reported that liming doubled the relative abundance of Pezizales in a boreal forest soil. ...
... Ge et al. (2017) also suggested that soil nutrients were potentially responsible for the proliferation of Pezizales. Majority of species in order Pezizales order have significant saprotrophic capacity (Tedersoo et al., 2006;Tedersoo et al., 2010), particularly a wide array of hydrolytic and phenol-oxidizing capacities (Egger, 1986). Therefore, the marked increase in Pezizales in NPK + PigManure promoted nutrient cycling in Ultisols. ...
Fungal communities play a critical role in regulating soil nutrient cycling and plant growth. However, the effects of long-term mineral and organic fertilization on fungal communities in Ultisols remain largely unknown. Soil samples from a 27-year fertilization experiment were used to investigate fungal communities through high-throughput sequencing along with literature data. The study involved seven treatments: no fertilization (Control), mineral NPK fertilizer (NPK), NPK fertilizer plus lime (NPK + Lime), NPK fertilizer plus peanut straw (NPK + PeanStraw), NPK fertilizer plus rice straw (NPK + RiceStraw), NPK fertilizer plus radish residue (NPK + RadResidue), and NPK fertilizer plus pig manure (NPK + PigManure). Long-term amendment of mineral and organic fertilizers did not alter fungal diversity in strong acidic Ultisols (original soil pH = 4.96). Meta-analysis of 60 global measurements in literature showed that fertilizer-induced decreases in fungal diversity (Hedge's d = −0.36; p < 0.05) occurred mainly in soils with initial pH >6 rather than <6, potentially due to the decrease in soil pH in fertilized soils, with mineral fertilizers having stronger effects than organic amendments. Ascomycota was the dominant phylum in all treatments, accounting for 75–90% of the total sequences, followed by Basidiomycota (5.9–11%), which are consistent with data from literature. Application of NPK + Lime and NPK + PigManure shifted fungal community structure by increasing relative abundance of Hypocreales and Pezizales, respectively, compared with the Control, while amendment with NPK alone or in combination with crop residues did not. Soil organic carbon, effective diffusion coefficient of oxygen, and pH were the three most critical determinants of fungal community structure. Overall, our results suggest that fungal community structure rather than fungal diversity responded to the application of NPK + Lime or NPK + PigManure but not NPK+ plant residues in test Ultisols, and lack of response in fungal diversity to fertilization was potentially due to the particularly low soil pH in test soils.
... Ectomycorrhizae of Helvella sp. Ho-TS601 was described by Tedersoo et al., (2006) and was characterized by orange-brown to red-brown morphotypes and whitish tips when young. The mantle organization was cellular with large spherical to subepidermoid cells, without emanating hyphae. ...
... La familia Helvellaceae es la mejor representada con cinco especies, seguida de Pyronemataceae con cuatro, Pezizaceae y Sarcoscyphaceae con dos y por último Pseudombrophilaceae, Pulvinulaceae y Sarcosomataceae con un solo taxón cada una. El género mejor representado es Helvella con cinco especies, lo que coincide con Medel (2007) (2013) la registraron asociada con Pinus L. Estos resultados coinciden con Tedersoo et al. (2006) quienes indicaron que los Pezizales son generalmente los miembros dominantes en las comunidades ectomicorrizógenas del Phylum Ascomycota. Por su parte todas las especies fimícolas (Cheilymenia coprinaria, Pseudombrophila fuscolilacina y Trichophaeopsis latispora) se encontraron sobre estiércol vacuno y tienden a ser cosmopolitas (Nmichi et al., 2017). ...
Antecedentes y Objetivos:
Pezizales es uno de los órdenes del reino Fungi más estudiados en el mundo y el segundo grupo de ascomicetos mejor conocido en México con 185 especies. En contraste, existen solo 23 especies registradas para Sonora. El objetivo de este estudio fue determinar la riqueza taxonómica de Pezizales asociados al bosque de pino-encino en una localidad del municipio de Yécora, Sonora, México.
Métodos:
Se realizaron cinco muestreos estacionales en bosque de pino-encino de Los Pilares, Yécora, Sonora durante los años 2020-2021. La determinación taxonómica se hizo con claves especializadas con base en la caracterización macro- y micromorfológica de los especímenes.
Resultados clave:
Se determinaron 16 especies de Pezizales distribuidas en siete familias: Helvellaceae (5), Pezizaceae (2), Pseudombrophilaceae (1), Pulvinulaceae (1), Pyronemataceae (4), Sarcosomataceae (1) y Sarcoscyphaceae (2). Doce especies son nuevos registros para Sonora y seis para México: Geopyxis deceptiva, Helvella dryophila, Plectania milleri, Pseudombrophila fuscolilacina, Pseudopithyella magnispora y Tricophaeopsis latispora. Además, los tres últimos taxones se citan por primera vez para el continente americano.
Conclusiones:
El catálogo de Pezizales de Sonora se incrementó a 35 especies; no obstante, es importante dar continuidad a estudios que incluyan análisis ecológicos y filogenéticos de este grupo de hongos.
... Most of these species are soil saprotrophs even in disturbed conditions, including a minority that has evolved peculiar adaptation to extreme conditions, such as burnt soils [111]. However, evolved soils and less disturbed conditions are consistent with higher diversity in the Pezizales community as well as with the possible occurrence of species proposed to be mycorrhizals [112]. Leotiomycetes were mostly represented by the orders Helotiales and Thelebolales, whose respective taxonomic relationship is still "contentious" [113], as well as the possible accomodation of certain taxa in different orders, such as the Leotiales Korf and Lizon. ...
Plastic pollution is a growing environmental issue that results in its accumulation and persistence in soil for many decades, with possible effects on soil quality and ecosystem services. Microorganisms, and especially fungi, are a keystone of soil biodiversity and soil metabolic capacity. The aim of this research was to study soil fungal biodiversity and soil microbial metabolic profiles in three different sites in northern Italy, where macro- and microplastic concentration in soil was measured. The metabolic analyses of soil microorganisms were performed by Biolog EcoPlates, while the ITS1 fragment of the 18S ribosomal cDNA was used as a target for the metabarcoding of fungal communities. The results showed an intense and significant decrease in soil microbial metabolic ability in the site with the highest concentration of microplastics. Moreover, the soil fungal community composition was significantly different in the most pristine site when compared with the other two sites. The metabarcoding of soil samples revealed a general dominance of Mortierellomycota followed by Ascomycota in all sampled soils. Moreover, a dominance of fungi involved in the degradation of plant residues was observed in all three sites. In conclusion, this study lays the foundation for further research into the effect of plastics on soil microbial communities and their activities.
... Some species also have been shown to be ectomycorrhizal, with the potential to rapidly fruit and establish symbiotic relationships with new seedlings. For this reason, they are often the dominant taxon in early forest succession ecosystems (Tedersoo et al., 2006). Furthermore, members of the Pezizaceae have been found to be dominant in Betula ermanii (Erman's birch) boreal forests with an admixture of Sasa kurilensis (bamboo) (Kong et al., 2017). ...
Soil fungal communities are critical components in soil ecosystems, but experimental researches on their responses to the silver birch succession are limited. Arbuscular mycorrhizal (AM) fungi and glomalin-related soil protein (GRSP) – a type of glycoprotein produced by hyphae of AM fungi, are highly correlated with soil physicochemical parameters and are sensitive to changes in the soil environment. This study aimed to analyze the dynamics of a soil fungal community, with particular emphasis on the AM fungi and GRSP contents and their responses to a silver birch succession on abandoned post-arable land. The studies were conducted in central Poland and covered five stands that included arable field (AF) and fallow (FA) land, and 8-year-old/young (YS), 33-year-old/middle (MS), and 40-year-old/old (OS) successions of silver birch. The diversity and compositions of the fungal communities were examined using ITS high-throughput gene sequencing. We found that the dominant soil fungal phylum transitioned from Olpidiomycota through Ascomycota to Basidiomycota with the change from AF to OS. Silver birch development increased the soil fungal diversity and richness compared with that of the AF soil, but these decreased compared with the FA soil. The predominant fungi in the soils under silver birch development belonged to the families Pezizaceae, Russulaceae, and Cortinariceae. The birch succession significantly decreased the abundance of potential pathotrophs and increased the relative abundance of symbiotrophic fungi. The AM fungi abundance varied across the successional stages and was affected by plant cover and N content, and positively correlated with the EE-GRSP and T-GRSP contents. Additionally, the EE-GRSP and T-GRSP contents positively correlated with the TOC, N and SOM content, and Tp, and negatively correlated with Bd. Across the successional stages, the YS was devoid of AM fungi and characterized by the lowest EE-GRSP T-GRSP (1.89 mg g⁻¹), Tp (43.4%), and TOC (7.3 g kg⁻¹) and P (11.7 g kg⁻¹) contents. In summary, the development of young silver birch on generally poor Brunic Arenosols tends to have a negative effect on the soil fungal community and selected soil properties, but these effects ease over time.
... Previous research reported an abundance of Pezizales ECM with B. vivipara (Tedersoo et al., 2003;Izzo, Agbowo & Bruns, 2005), which was also confirmed here. Most of the identified Pezizales sequences matched sequences from sporocarp tissue of the genera Genea, Peziza, Sarcosphaera, Tarzetta, and Trichophaea, which are already known as major representatives of the Pezizales from northern temperate forests (Tedersoo et al., 2006). In spite of the high ECM diversity detected, the non-asymptotic shape of the species accumulation curve suggests that many fungal species remained undetected (Fig. S2). ...
Bistorta vivipara is a widespread herbaceous perennial plant with a discontinuous pattern of distribution in arctic, alpine, subalpine and boreal habitats across the northern Hemisphere. Studies of the fungi associated with the roots of B. vivipara have mainly been conducted in arctic and alpine ecosystems. This study examined the fungal diversity and specificity from root tips of B. vivipara in two local mountain ecosystems as well as on a global scale. Sequences were generated by Sanger sequencing of the internal transcribed spacer (ITS) region followed by an analysis of accurately annotated nuclear segments including ITS1-5.8S-ITS2 sequences available from public databases. In total, 181 different UNITE species hypotheses (SHs) were detected to be fungi associated with B. vivipara , 73 of which occurred in the Bavarian Alps and nine in the Swabian Alps–with one SH shared among both mountains. In both sites as well as in additional public data, individuals of B. vivipara were found to contain phylogenetically diverse fungi, with the Basidiomycota, represented by the Thelephorales and Sebacinales, being the most dominant. A comparative analysis of the diversity of the Sebacinales associated with B. vivipara and other co-occurring plant genera showed that the highest number of sebacinoid SHs were associated with Quercus and Pinus , followed by Bistorta . A comparison of B. vivipara with plant families such as Ericaceae, Fagaceae, Orchidaceae, and Pinaceae showed a clear trend: Only a few species were specific to B. vivipara and a large number of SHs were shared with other co-occurring non- B. vivipara plant species. In Sebacinales, the majority of SHs associated with B. vivipara belonged to the ectomycorrhiza (ECM)-forming Sebacinaceae, with fewer SHs belonging to the Serendipitaceae encompassing diverse ericoid–orchid–ECM–endophytic associations. The large proportion of non-host-specific fungi able to form a symbiosis with other non- B. vivipara plants could suggest that the high fungal diversity in B. vivipara comes from an active recruitment of their associates from the co-occurring vegetation. The non-host-specificity suggests that this strategy may offer ecological advantages; specifically, linkages with generalist rather than specialist fungi. Proximity to co-occurring non- B. vivipara plants can maximise the fitness of B. vivipara , allowing more rapid and easy colonisation of the available habitats.
... Geopora species form rather small sporocarps that are either hypogeous throughout their life span or emerge and are apothecial. So these taxa are difficult to find or to describe and are rarely classified to species (Gehring et al. 1998, Fujimura et al. 2005, Tedersoo et al. 2006, Hrynkiewicz et al. 2009, Ishida et al. 2009, Sthultz et al. 2009, Wei et al. 2010, Gordon & Gehring 2011. Moreover, morphological features tend to overlap among the species in Geopora making the taxonomy of this genus complicated. ...
... Because tree savannas play important ecological, social, and economic roles for societies (e.g., Conedera et al., 2016), understanding their functioning and analyzing their biodiversity patterns has been subject of much attention (Bugalho et al., 2011). Within their soils, these ecosystems concentrate some of the richest ECM communities described so far (Tedersoo et al., 2006;Morris et al., 2008;Baptista et al., 2015;Reis et al., 2018) and harbor highly specific fungal assemblies dominated by ascomycetes, in response to a unique combination of environmental and anthropic drivers (Dickie et al., 2009). ...
Trees acquire hydric and mineral soil resources through root mutualistic associations. In most boreal, temperate and Mediterranean forests, these functions are realized by a chimeric structure called ectomycorrhizae. Ectomycorrhizal (ECM) fungi are highly diversified and vary widely in their specificity toward plant hosts. Reciprocally, association patterns of ECM plants range from highly specialist to generalist. As a consequence, ECM symbiosis creates interaction networks, which also mediate plant–plant nutrient interactions among different individuals and drive plant community dynamics. Our knowledge of ECM networks essentially relies on a corpus acquired in temperate ecosystems, whereas the below-ground facets of both anthropogenic ECM forests and inter-tropical forests remain poorly investigated. Here, we successively (1) review the current knowledge of ECM networks, (2) examine the content of early literature produced in ECM cultivated forests, (3) analyze the recent progress that has been made in understanding the place of ECM networks in urban soils, and (4) provide directions for future research based on the identification of knowledge gaps. From the examined corpus of knowledge, we reach three main conclusions. First, the emergence of metabarcoding tools has propelled a resurgence of interest in applying network theory to ECM symbiosis. These methods revealed an unexpected interconnection between mutualistic plants with arbuscular mycorrhizal (AM) herbaceous plants, embedding ECM mycelia through root-endophytic interactions. This affinity of ECM fungi to bind VA and ECM plants, raises questions on the nature of the associated functions. Second, despite the central place of ECM trees in cultivated forests, little attention has been paid to these man-made landscapes and in-depth research on this topic is lacking. Third, we report a lag in applying the ECM network theory to urban soils, despite management initiatives striving to interconnect motile organisms through ecological corridors, and the highly challenging task of interconnecting fixed organisms in urban greenspaces is discussed. In particular, we observe a pauperized nature of resident ECM inoculum and a spatial conflict between belowground human pipelines and ECM networks. Finally, we identify the main directions of future research to make the needed link between the current picture of plant functioning and the understanding of belowground ECM networks.
... Perić and Perić (2011) have found mycorrhizal association of G. arenicola with scattered trees of Cupressus sempervirens L. in Montenegro. Maia et al. (1996) (Tedersoo et al., 2006), we have not been able to determine ectomycorrhizal association for our new record of G. arenicola found next to Acer tataricum. Further studies are required to determine whether G. arenicola has ectomycorrhizal associations with Acer tataricum in Uzbekistan. ...
The first record of Geopora arenicola for Uzbekistan is reported from Nuratau Nature Reserve. The genus Geopora is also recorded for the first time in Uzbekistan. Ascocarps of the fungus at first are usually spherical, completely immersed in soil, later they emerge at the ground surface and open at the top. Mature apothecia have a central opening with torn edges and whitish to grayish hymenium surface. A description, distribution data, images of apothecia and micromorphological characters of the fungus are provided.
... Based on our limited material, we were not able to perform comprehensive anatomical observations of the typical ECM root tip structures (mantle and Hartig net) from J. deppeana roots that are needed to consider the species as dual mycorrhizal (Teste et al., 2019). Nonetheless, some ECM taxa such as Peziza and other Pezizalean fungi have been reported to form ectendomycorrhiza with a thin or fragmented mantle and poorly developed Hartig net (Tedersoo et al., 2006). Ectendomycorrhizal morphologies have been frequently reported in tropical regions, colonizing seedlings or as early-successional species following disturbances (Fujimura et al., 2005;Salgado Salomón et al., 2013;Alvarez-Manjarrez et al., 2018). ...
Competition for resources between arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) plants can alter belowground mycorrhizal communities, but few studies have investigated host effects on both AM and ECM communities. In Central Mexico, the AM plant Juniperus deppeana is frequently used for reforesting areas affected by soil erosion, while the surrounding native forests are dominated by ECM oak trees. Oaks are capable of associating with both AM and ECM fungi during part of their life cycle (a feature known as dual mycorrhization) but it is unclear whether junipers possess such ability. To assess how juniper planting may affect belowground fungal interactions with oaks, we investigated mycorrhizal associations in J. deppeana and Quercus rugosa seedlings along a disturbance gradient: a native oak forest, a mixed Juniperus-Quercus population in secondary vegetation and a juniper site severely degraded by mining extraction. We measured root colonization and identified fungal communities using soil and root meta-barcoding of the ITS2 rDNA region. ECM fungal community composition was strongly affected by disturbance (regardless of host), while the community composition of AM fungi was mostly host-dependent, with a higher AM fungal richness in J. deppeana . Importantly, the fungal communities associated with Q. rugosa seedlings significantly changed in the vicinity of juniper trees, while those of J. deppeana seedlings were not affected by the presence of oak trees. Even though ECM fungal richness was higher in Q. rugosa and in the native forest, we detected a variety of ECM fungi associated exclusively with J. deppeana seedlings, suggesting that this plant species may be colonized by ECM fungi. Our results indicate that J. deppeana can alter ECM native fungal communities, with implications for its use in reforestation of mixed oak forests.
... It has been suggested that pezizomycetes EMF could offer a more beneficial cost-benefit ratio to their hosts than Basidiomycota, because they would be less robust [84]. The stout hyphae and thick-walled chlamydospores and ascospores of pezizalean may further contribute to their ability to persist under disturbed environmental conditions [85]. In our samples, the two most dominant Pezizales genera were Tuber spp. ...
There is a growing interest in plant microbiome’s engineering to optimize desired functions such as improved phytoremediation. This study is aimed at examining the microbial communities inhabiting the roots and rhizospheres of two Salix miyabeana cultivars that had been grown in a short-rotation intensive culture (SRIC) system for six years in a soil contaminated with the discharge from a petrochemical factory. DNA was extracted from roots and rhizospheric soils, and fungal ITS and bacterial and archaeal 16S rDNA regions were amplified and sequenced using Illumina MiSeq technology. Cultivars ‘SX61’ and ‘SX64’ were found to harbor a similar diversity of fungal, bacterial, and archaeal amplicon sequence variants (ASVs). As expected, a greater microbial diversity was found in the rhizosphere biotope than in the roots of both cultivars, except for cultivar ‘SX64’, where a similar fungal diversity was observed in both biotopes. However, we found that microbial community structures were cultivar- and biotope-specific. Although the implication of some identified taxa for plant adaptability and biomass production capacity remains to be explored, this study provides valuable and useful information regarding microbes that could potentially favor the implantation and phytoremediation efficiency of Salix miyabeana in mixed contamination sites in similar climatic environments.
... This class consists of one order (Pezizales), 23 families and an estimated 2000 species (Pfister & Healy, 2021). Species of Pezizomycetes include well-documented plant pathogens (Marek et al., 2009), ectomycorrhizal (ECM) fungi (Tedersoo et al., 2006) and saprobes (Hobbie et al., 2001;Hansen & Pfister, 2006). Some species colonize specific substrates, acting as parasites of bryophytes (D€ obbeler, 1997) or as specialized saprobes of dung (Pfister, 2015;Richardson, 2019) or postfire materials (Egger, 1986). ...
Fungal endophytes live asymptomatically within plants and are widespread inhabitants of leaves and other organs (Wilson, 1995). Similarly, endolichenic fungi live asymptomatically within lichens, occurring in healthy lichen thalli worldwide (Arnold et al., 2009). Endophytes and endolichenic fungi are ecologically similar, living in symbiosis with either a plant or the photobionts of lichens (Arnold et al., 2009), and both functional groups represent the same major lineages of fungi (U’Ren et al., 2012).
... However, we did find evidence of initial changes in the abundance of specific fungal ASVs, particularly in Pyronemataceae sp. and Russula (adjusted p-value < 0.01; log2Fold > 2). Although the specific nature of most Pyronemataceae is unknown, different members of the family have been characterized as saprobes or ectomycorrhizal [85,86], while Russula is a large ECM genus with both nitrophobic and nitrophilic species, and is typically dominant in older stands [71,78,87]. Within the other ASVs recruited by the roots, the nitrophobic Suillus was negatively affected by both arginine phosphate and ammonium nitrate ( Figure 5) while Piloderma, which has the ability to take up, use and deliver amino acids to Scots pine [88], responded positively to the addition of arginine phosphate but not ammonium nitrate ( Figure 5). ...
Scots pine (Pinus sylvestris L.) is one of the most economically important species to the Swedish forest industry, and cost-efficient planting methods are needed to ensure successful reestablishment after harvesting forest stands. While the majority of clear-cuts are replanted with pre-grown seedlings, direct seeding can be a viable option on poorer sites. Organic fertilizer has been shown to improve planted seedling establishment, but the effect on direct seeding is less well known. Therefore, at a scarified (disc trencher harrowed) clear-cut site in northern Sweden, we evaluated the effect of early, small-scale nitrogen addition on establishment and early recruitment of fungi from the disturbed soil community by site-planted Scots pine seeds. Individual seeds were planted using a moisture retaining germination matrix containing 10 mg nitrogen in the form of either arginine phosphate or ammonium nitrate. After one growing season, we collected seedlings and assessed the fungal community of seedling roots and the surrounding soil. Our results demonstrate that early, small-scale N addition increases seedling survival and needle carbon content, that there is rapid recruitment of ectomycorrhizal fungi to the roots and rhizosphere of the young seedlings and that this rapid recruitment was modified but not prevented by N addition.
... In the soil of ectomycorrhizal treatment of poplar plantation on the family level, Pyronemataceae, known as paraphyletic and ectomycorrhizal [73] former, was detected with lower relative abundances, while on the genus level Ocroconis belonging to the Pyronemataceae family and ectomycorrhizal symbionts containing the Pezizaceae family was represented with significantly higher abundance (Figure 6c,d). Thus, the relatively higher abundance of fungi belonging to Pezizaceae and Pyronemataceae in our study may be promoted by ectomycorrhizal inoculation [74][75][76]. In the present study, the data of control soil of plantations confirmed the findings of previous studies that reported the soil fungal community adaptation to different host tree plantations [77][78][79]. ...
The impact of chemical fertilization on rhizosphere soil communities is a growing concern due to the changes they cause on microbes in soil ecosystems. The present study aims to compare mycorrhizal inoculation and fertilizer applications on bacterial and fungal communities in rhizosphere soil of intensively cultivated Robinia pseudoacacia and Populus × euramericana plantations using the Illumina Miseq sequencing platform. Our results revealed that the different host plants and applied treatments did not significantly affect soil bacterial diversity, but interfered with native rhizosphere bacterial communities in plantation sites. In contrast, host plants and inorganic fertilizer had a strong effect at the family and genus level on the composition of soil fungal communities. In conclusion, our findings suggest that the structure and composition of the fungal community are more sensitive to the nutrient sources in soil than bacteria.
... In the functional group bar charts, all available functional groups (guilds) from FUNGuild were included with some modifications: SHs classified as fungal parasite-saprotroph and fungal parasiteundefined saprotroph were called fungal parasite/saprotroph; fungal parasite-protistan parasite was called putative fungal parasite; plant pathogen-plant saprotroph/undefined saprotroph/wood saprotroph combinations were called plant pathogen/saprotroph; endophyte-litter saprotroph/soil saprotroph/undefined saprotroph/wood saprotroph were called putative endophyte/saprotroph; combinations of different saprotrophic classification were called saprotrophs, and any other SHs with a functional classification with several possibilities were assigned as unknown. See Supplementary Table 1 for functional groups and exploration type assignments (Agerer, 2001(Agerer, , 2006Tedersoo et al., 2006;Lilleskov et al., 2011;Katanic et al., 2014), and Supplementary Table 2 for relative abundances of the 446 most common identified SHs (rarefied and not rarefied data). In multivariate plots, showing the most common SHs (see below), functional groups were simplified, using ECM, saprotroph, plant pathogen, animal pathogen, and unknown. ...
Soil fungi are strongly affected by plant species or genotypes since plants modify their surrounding environment, but the effects of plant genotype diversity on fungal diversity and function have not been extensively studied. The interactive responses of fungal community composition to plant genotypic diversity and environmental drivers were investigated in Salix biomass systems, posing questions about: (1) How fungal diversity varies as a function of plant genotype diversity; (2) If plant genotype identity is a strong driver of fungal community composition also in plant mixtures; (3) How the fungal communities change through time (seasonally and interannually)?; and (4) Will the proportion of ECM fungi increase over the rotation? Soil samples were collected over 4 years, starting preplanting from two Salix field trials, including four genotypes with contrasting phenology and functional traits, and genotypes were grown in all possible combinations (four genotypes in Uppsala, Sweden, two in Rostock, Germany). Fungal communities were identified, using Pacific Biosciences sequencing of fungal ITS2 amplicons. We found some site-dependent relationships between fungal community composition and genotype or diversity level, and site accounted for the largest part of the variation in fungal community composition. Rostock had a more homogenous community structure, with significant effects of genotype, diversity level, and the presence of one genotype ("Loden") on fungal community composition. Soil properties and plant and litter traits contributed to explaining the variation in fungal species composition. The within-season variation in composition was of a similar magnitude to the year-to-year variation. The proportion of ECM fungi increased over time irrespective of plant genotype diversity, and, in Uppsala, the 4-mixture showed a weaker response than other combinations. Species richness was generally higher in Uppsala compared with that in Rostock and increased over time, but did not increase with plant genotype diversity. This significant site-specificity underlines the need for consideration of diverse sites to draw general conclusions of temporal variations and functioning of fungal Hoeber et al. Plant Genotypes and Soil Fungi communities. A significant increase in ECM colonization of soil under the pioneer tree Salix on agricultural soils was evident and points to changed litter decomposition and soil carbon dynamics during Salix growth.
... the abundance of Helotiaceae may be related to soil nutrient is C:N ratio. Tedersoo et al. (2006) revealed that some pezizalean species were distributed in the forests with a high pH, which was consistent with our findings. In addition, it was unexpected that the abundance of ascomycete family Nectriaceae was very low (<0.1%) in our soil. ...
Liming is an effective agricultural practice and is broadly used to ameliorate soil acidification in agricultural ecosystems. Our understanding of the impacts of lime application on the soil fungal community is scarce. In this study, we explored the responses of fungal communities to liming at two locations with decreasing soil pH in Oregon in the Pacific Northwest using high-throughput sequencing (Illumina MiSeq). Our results revealed that the location and liming did not significantly affect soil fungal diversity and richness, and the impact of soil depth on fungal diversity varied among locations. In contrast, location and soil depth had a strong effect on the structure and composition of soil fungal communities, whereas the impact of liming was much smaller, and location- and depth-dependent. Interestingly, families Lasiosphaeriaceae, Piskurozymaceae, and Sordariaceae predominated in the surface soil (0–7.5 cm) and were positively correlated with soil OM and aluminum, and negatively correlated with pH. The family Kickxellaceae which predominated in deeper soil (15–22.5 cm), had an opposite response to soil OM. Furthermore, some taxa in Ascomycota, such as Hypocreales, Peziza and Penicillium , were increased by liming at one of the locations (Moro). In conclusion, these findings suggest that fungal community structure and composition rather than fungal diversity responded to location, soil depth and liming. Compared to liming, location and depth had a stronger effect on the soil fungal community, but some specific fungal taxa shifted with lime application.
... Once hosts become more productive, Wilcoxina quickly loses its advantage over other mycorrhizal fungi, as it is a poor competitor (Mikola et al., 1964). Ectomycorrhizal Pezizales are prominent members of early successional forests, forest edges, drought-prone sites, disturbed sites, and in nutrient-poor soils (Tedersoo et al., 2006). ...
We provide the first analysis of the fungi associated with a very special habitat, the aeroponic roots found in caves and mines in New Brunswick, Canada. Fungal diversity was assessed by Illumina sequencing using three complementary primer sets targeting ribosomal RNA genes, and roots were identified using the non-coding trnH-psbA spacer. Early colonizing ectomycorrhizal fungi such as Agaricales, Helotiales, Pezizales, and Thelephorales were predominant. Saprotrophs, endophytes and plant pathogens were also present, but Glomeromycota (arbuscular mycorrhizal fungi) were not detected. Fungal root communities were generally most similar within sites. Fungal diversity was inversely correlated with winter dark zone temperatures and distance from the entrance. By using a combination of three primer sets, we detected more fungal taxa than with any one primer set. This study adds to the understanding of these subterranean ecosystems and suggests that future studies investigate factors limiting the presence of late-stage ectomycorrhizal fungi and Glomeromycota.
... Unlike the CK and CN soils, most of the microbial enrichment in CNS soil was beneficial. For example, Pezizaceae dominates the beneficial ectomycorrhizal fungal communities [51]. Cephalotheca (C. ...
... accounting for almost a quarter of the total number of sequence reads. The Pyronemataceae family, shown to be one of the major dominants in the AEl horizon and the first-ranked in abundance in the lower horizons, are very diverse ecophysiologically [48]; in this study, the family was represented by three explicitly classified genera, namely Wilcoxina, Tarzetta, and Boubovia, all being common mycorrhizal fungi [49]. However, their dominance was not associated with subsoil environments before. ...
Vast areas of land in the forest-steppe of West Siberia are occupied by birch forests, the most common ecosystems there. However, currently, little is known about the microbiome composition in the underlying soil, especially along a sequence of soil genetic horizons. The study aimed at inventorying microbiome in genetic horizons of a typical Phaeozem under undisturbed birch forest in West Siberia. Bacteria and fungi were studied using 16S rRNA genes’ and ITS2 amplicon sequencing with Illumina MiSeq. Proteobacteria and Acidobacteria together accounted for two-thirds of the operational taxonomic units (OTUs) numbers and half of the sequences in each genetic horizon. Acidobacteria predominated in eluvial environments, whereas Proteobacteria, preferred topsoil. The fungal sequences were dominated by Ascomycota and Basidiomycota phyla. Basidiomycota was the most abundant in the topsoil, whereas Ascomycota increased down the soil profile. Thelephoraceae family was the most abundant in the A horizon, whereas the Pyronemataceae family dominants in the AEl horizon, ultimately prevailing in the subsoil. We conclude that soil genetic horizons shape distinct microbiomes, therefore soil horizontation should be accounted for while studying undisturbed soils. This study, representing the first description of bacterio- and mycobiomes in genetic horizons of the Phaeozem profile, provides a reference for future research.
... Molecular data suggest that this species deserves its own genus ( fig. 1) and we propose to name it Aurantiolachnea. it is also interesting to note that we did not find any correspondence with some ecM sequences using the iTs gene, suggesting the species to be saprobic, another difference with H. hemisphaerica which forms ectomycorrhizas (Tedersoo et al., 2006). 3: 84 (1994). ...
Recent collections of unknown Trichophaea-like discomycetes made in Europe enabled the authors to explore the taxonomy of Trichophaea and allies, based on morphological, ecological and molecular data. Our 3-gene phylogeny confirms the paraphyly of the genus Trichophaea and designs a new systematics for this group of cup-fungi. Three new genera are published to accommodate several species previously assigned to Trichophaea or morphologically close genera: Perilachnea gen. nov. with Lachnea hemisphaerioides as type-species, Aurantiolachnea gen. nov. with Lachnea solsequia as type-species, and Parawilcoxina gen. nov. with P. inexpectata sp. nov. as type-species. some species of the genus Paratrichophaea belong to the cleistothecial genus Lasiobolidium, and furthermore two new species, L. trachysporum and L. coprophilum, are described. Paratrichophaea macrocystis is also combined in Lasiobolidium. Finally, three new species of Chaetothiersia, C. laricina, C. cupressicola and C. eguttulata are described. a new species of Perilachnea, P. ochraceoflava, is outlined from Italy, and a new species of Trichophaeopsis, T. asturiensis, is described from Spain. A total of 15 species are described and illustrated herein. Keys are provided.
... J. Schröt. (the Violet Crown Cup) is an ectomycorrhizal ascomycete fungus of the Pezizaceae family (Tedersoo et al., 2006) reported from Europe and North America, sometimes under its synonymous names S. crassa (Santi ex Steudel) Pouz., S. dargelasii (Gachet) Nannf., and S. eximia (Dur. & Lév.) R. Maire (Fig. 1). ...
The Violet Crown Cup, Sarcosphaera coronaria, is a rather inconspicuous mushroom, but with an interesting and unresolved mystery. In earlier days, the mushroom was considered edible, but several poisonings were reported in the early 20th century. The reason for the seemingly sporadic toxicity of S. coronaria is still unknown. One possible explanation is arsenic, since Crown Cups can take up high amounts of this element. We investigated the arsenic concentration and arsenic speciation in S. coronaria with inductively coupled plasma mass spectrometry (ICPMS) and HPLC coupled to ICPMS and found up to incredible 0.9% As (dry mass). Most of it was present as methylarsonic acid (MA), a less toxic form of this element. However, low concentrations of the highly toxic methylarsonous acid [MA (III)] were also detected. The amounts were too low to pose an acute risk for consumers, but the concentration of MA (III) significantly increased during simulated gastric digestion. We could not unambiguously identify arsenic as the toxic constituent of S. coronaria, but we demonstrated that the extremely toxic MA (III) can be formed under certain circumstances, which should be carefully investigated in future.
... Ceratobasidium, Chloridium, Cortinarius, Lactarius, Piloderma, Russula, Sebacina, Trichophaea and Tuber were shared in the mineral-filled mesh bags and the control. Trichophaea, an ECM genus confirmed by Tedersoo et al. (2006), is the most dominant in different treatments. ...
Ectomycorrhizal (ECM) fungi can promote the nutrient uptake of plants from soil minerals by bioweathering. However, effects of different minerals on ECM fungal colonization and bacterial community structures in the soil remains poorly documented. Here, we investigated ECM fungal composition and bacterial communities in different mineral-filled mesh bags buried in forest soil. Control (filled with quartz, which has little nutrients for plants) and mineral (apatite, potash feldspar and serpentine) -filled mesh bags were buried in E-horizon soil for six months. After incubation, the contents of available elements in bags were determined, bacterial population sizes were quantified by quantitative PCR, and bacterial and ECM fungal community structures in mesh bags were assessed using high-throughput sequencing. The results showed that dozens of ECM fungal species colonized in different mesh bags, of which 17, 54 and 47 ECM species were observed in apatite-, potash feldspar- and serpentine-filled bags, respectively. Ectomycorrhizal fungal composition and bacterial community structure are affected significantly by mineral types. Pseudomonas, Sphingomonas, Bacillus and Paenibacillus, known for high weathering potential, were the preponderant bacteria in mineral-filled bags compared to the control. Ectomycorrhizal fungi are able to selectively colonize mesh bags based on mineral types, and may have a certain influence on the formation of bacterial community structure, implying a possible cooperation of ECM fungi and bacteria in soil mineral weathering.
... The 90 t ha −1 amendment in the forest soil caused increased ITS gene copy numbers and a fungal community shift with increased dominance of Mortierella, Peziza and Hypocreales. These fungi are opportunistic saprotrophs with high growth rates and can exploit readily available nutrients before other fungi arrive (Carlile, Watkinson and Gooday 2001;Tedersoo et al. 2006;Druzhinina, Shelest and Kubicek 2012). Further, some Peziza spp. ...
Recycling of wood ash from energy production may counteract soil acidification and return essential nutrients to soils. However, wood ash amendment affects soil physicochemical parameters that control composition and functional expression of the soil microbial community. Here, we applied Total RNA-sequencing to simultaneously assess the impact of wood ash amendment on the active soil microbial communities and the expression of functional genes from all microbial taxa. Wood ash significantly affected the taxonomic (rRNA) as well as functional (mRNA) profiles of both agricultural and forest soil. Increase in pH, electrical conductivity, dissolved organic carbon and phosphate were the most important physicochemical drivers for the observed changes. Wood ash amendment increased the relative abundance of the copiotrophic groups Chitinonophagaceae (Bacteroidetes) and Rhizobiales (Alphaproteobacteria) and resulted in higher expression of genes involved in metabolism and cell growth. Finally, Total RNA-sequencing allowed us to show that some groups of bacterial feeding protozoa increased concomitantly to the enhanced bacterial growth, which shows their pivotal role in the regulation of bacterial abundance in soil.
... We determined sporocarp species richness from each quadrat. To test whether functional groups of sporocarps will differ in the high-severity burn patches compared to moderate-severity or unburned areas, we separated species into different functional groups (either EM or saprotrophic) based on common consensus from past studies (e.g., Tedersoo et al., 2006;Tedersoo and Smith, 2013). ...
Over the past three decades, wildfires in southwestern US ponderosa pine (Pinus ponderosa Lawson & C. Lawson) forests have increased in size and severity. These wildfires can remove large, contiguous patches of mature forests, alter dominant plant communities and increase woody debris, potentially altering fungal community composition. Additionally, post-fire conditions may shift dominant fungal functional groups from plant-symbiotic ectomycorrhizal (EM) fungi to more decomposer saprotrophic fungi. We investigated the long-term (13 years post-wildfire) effect of fire severity on 1) fungal sporocarp density, functional groups and community composition and 2) EM colonization and community composition from naturally regenerating ponderosa pine seedlings on the Pumpkin Fire that burned in 2000 in Arizona, USA. Plots were located in four burn severity classes: unburned, moderate-severity, and two high-severity (defined as 100% tree mortality) classes, either adjacent to residual live forest edges (edge plots), or >200 m from any residual live trees (interior plots). We found that high-severity burn plots had a unique sporocarp community composition, and a shift in dominant sporocarp functional groups, with 5–13 times lower EM sporocarp densities, and 4–7 times lower EM sporocarp species richness compared to unburned and moderate-severity plots. In contrast, saprotrophic sporocarp densities and richness were similar among burn severity classes, even with the large amount of coarse wood in the high-severity burn patches. Regenerating ponderosa pine seedlings had similar EM colonization and richness among severity classes, yet high-severity interior plots had a different community composition and a lower relative abundance of EM species compared to moderate-severity burn plots. Taken together, our results suggest that large patches of high-severity fire have long-term consequences for both EM sporocarp and root tip communities. Because EM fungal species vary in function, the limited species pool available in interior high-severity burn patches may influence pine recovery.
... Tamm & al. (2010) reviewed the history of the genus Geopora and confirmed that delimitations of species within Geopora are difficult. All known taxa are ectomycorrhizal (Tedersoo & al. 2006) but we have not been able to determine the mycorrhizal associate(s) for our new species. The ectomycorrhizal host could be Pinus roxburghii, which grows near the site where this species has been repeatedly collected in the Botanical Garden Geopora ahmadii is distinct from other Geopora species based on apothecial shape, partial immersion of the apothecium in the soil, hymenial color, and ascospore size. ...
A new species, Geopora ahmadii, is described and illustrated based on material from Punjab, Pakistan. This species is characterized by sessile, cup- to saucer-shaped, partly immersed apothecia with whitish to grayish hymenial surfaces; broad ellipsoid, mostly uniguttulate ascospores; and brown excipular hairs. Phylogenetic analyses of the nrDNA ITS region with maximum parsimony, maximum likelihood, and Bayesian inference methods reveal that G. ahmadii is distinct from other described Geopora species. A collection previously identified as Geopora arenosa from Rawalakot, Pakistan, likely represents a second locality of G. ahmadii.
... Results reported by Rubini et al. (2011) suggest that T. melanosporum haploids that colonize all EM roots locally, and have access to tree photosynthates, act as the female parent; they open the possibility that males are smaller, perhaps dominated individuals that co-occur in soil and are possibly forced to invest less in reproduction. Such a particularity does not apply to Hymenomycetes dikaryons, and highlights the need for investigation of more Ascomycetes species, since Ascomycetes make up a significant component of EM communities (Egger 2006;Tedersoo et al. 2006;Grelet et al. 2010), even if most are rare EM species (with exception of C. geophilum, see below). ...
... Generally, two main fruit body types can be distinguished: epigeous with active spore discharge adapted mainly to wind dispersal and hypogeous without active spore discharge and spore dispersal mostly by animals or soil/water movement. Hypogeous fungi have mostly arisen repeatedly from epigeous ancestors many times during evolution both within the Ascomycota and Basidiomycota (Trappe et al. 2009), e.g., at least ten times within the Pezizales (Tedersoo et al. 2006). Even within epigeous fruit bodies, there are several types that do not appear to be well adapted to wind dispersal, e.g., clavarioid and resupinate forms, especially if these occur on the lower side of branches near to or on the soil. ...
Dispersal of mycorrhizal fungi via animals and the importance for the interacting partners’ life history as well as for ecosystems is an understudied topic. In this review, we describe the available evidence and the most important knowledge gaps and finally suggest ways to gain the missing information. So far, 33 articles have been published proving a successful transfer of mycorrhizal propagules by animals. The vast majority of research on invertebrates was focused on arbuscular mycorrhizal (AM) fungi, whereas papers on vertebrates (mainly rodents and artiodactyls) equally addressed ectomycorrhizal (ECM) and AM fungi. Effective dispersal has been mostly shown by the successful inoculation of bait plants and less commonly by spore staining or germination tests. Based on the available data and general knowledge on animal lifestyles, collembolans and oribatid mites may be important in transporting ECM fungal propagules by ectozoochory, whereas earthworms, isopods, and millipedes could mainly transfer AM fungal spores in their gut systems. ECM fungal distribution may be affected by mycophagous dipterans and their hymenopteran parasitoids, while slugs, snails, and beetles could transport both mycorrhizal groups. Vertebrates feeding on fruit bodies were shown to disperse mainly ECM fungi, while AM fungi are transported mostly accidentally by herbivores. The important knowledge gaps include insufficient information on dispersal of fungal propagules other than spores, the role of invertebrates in the dispersal of mycorrhizal fungi, the way in which propagules pass through food webs, and the spatial distances reached by different dispersal mechanisms both horizontally and vertically.
... New Phytologist genus, Rhizopogon (Taylor & Bruns, 1999). In our study the EMF that persisted beneath dead trees or in sites with high host mortality were ascomycetes or species of Rhizopogon, which can retain viability in the absence of a host through the production of long-lived spores (Tedersoo et al., 2006;Bruns et al., 2009). ...
Successive droughts have resulted in extensive tree mortality in the southwestern United States. Recovery of these areas is dependent on the survival and recruitment of young trees. For trees that rely on ectomycorrhizal fungi (EMF) for survival and growth, changes in soil fungal communities following tree mortality could negatively affect seedling establishment. We used tree‐focused and stand‐scale measurements to examine the impact of pinyon pine mortality on the performance of surviving juvenile trees and the potential for mutualism limitation of seedling establishment via altered EMF communities. Mature pinyon mortality did not affect the survival of juvenile pinyons, but increased their growth. At both tree and stand scales, high pinyon mortality had no effect on the abundance of EMF inocula, but led to altered EMF community composition including increased abundance of Geopora and reduced abundance of Tuber. Seedling biomass was strongly positively associated with Tuber abundance, suggesting that reductions in this genus with pinyon mortality could have negative consequences for establishing seedlings. These findings suggest that while mature pinyon mortality led to competitive release for established juvenile pinyons, changes in EMF community composition with mortality could limit successful seedling establishment and growth in high mortality sites. This article is protected by copyright. All rights reserved.
Pinus massoniana is an important afforestation and industrial timber tree species in China; However, its growth and productivity are often suffered from phosphorus deficiency. Phosphate-solubilizing microorganisms (PSMs) can increase phosphorus efficiency and may have the important potential for use in forestry ecosystem. In order to evaluate whether the co-inoculation of PSMs would enhance plant growth than single inoculation, and better understand the synergistic mechanisms of PSM compound strains regulating P. massoniana growth, we used plant physiology, microbiome, and transcriptome technologies to assess the effects of combined PSMs on plant growth, rhizosphere microecology and plant physiological system. The results demonstrated that combined endophytic fungus (Penicillum oxalicum G17) and rhizosphere bacteria (Burkholderia sp. WJ27) significantly increased phosphate-dissolving ratio and promoted P. massoniana growth compared with a single strain or non-inoculation. The combination of G17 and WJ27 strains (G17&WJ27) evidently enhanced soil nutrients, as well as P, N, and K contents in seedlings. Although the diversities of fungi and bacteria were reduced under G17&WJ27 treatment, the relative abundances of ectomycorrhizal fungi (Trichophaea and Thelephora) and plant growth-promoting rhizobacteria (Sphingomonas, Burkholderia, Chitinophaga, Ramlibacter, and Rhodanobacter) increased. Transcriptome profiles showed that compared with non-inoculated plants, there were 7115 differentially expressed genes (DEGs) identified in G17&WJ27 treatment, which were involved in various biological pathways associated with growth regulation, including photosynthesis, sugar metabolism, antioxidant enzyme activity, plant hormones, amino acid biosynthesis, and inorganic phosphate transporters. This study would provide a theoretical basis for the development of compound microbial fertilizers for cultivation and management of Masson pine forests.
Black truffle plantations are established on the basis that Tuber melanosporum Vittad. spreads from artificially inoculated trees. Although truffle cultivation has progressed tremendously over the past 30 years, the ecological processes underlying T. melanosporum mycelium expansion and its interactions with the rest of the fungal community over time are not completely understood. Controversy also exists on how mating type distribution evolves with time and its incidence on fruiting. We studied the soil fungal community and mating type distribution in plantations before truffle production (3, 5 and 7 years and after establishment) and during the production period (10, 14 and 20 years) at three distances from the tree stem: 40, 100 and 200 cm. We found that T. melanosporum developed steadily over the years as extraradical mycelium, first at the nearest part of the tree and later up to 200 cm. T. melanosporum development was not correlated with changes in other ectomycorrhizal fungi and was negatively correlated with lower relative abundance of arbuscular mycorrhizal fungi and non-root associated guilds such as moulds, yeasts and plant pathogens. Mating type frequency did not change across years. Twenty years after establishment no signs of replacement of T. melanosporum by other fungi nor biases in mating type abundance were observed in soil mycelia, indicating that T. melanosporum can colonize and dominate the surrounding soil in mature Quercus ilex L. trees for a long time.
The true truffles, Tuber aestivum Vittad., T. borchii Vittad., T. magnatum Picco and T. melanosporum Vittad., are among the most studied fungal species; they also have a high economic value due to their special aromatic and nutritional properties that make them a much sought delicacy. Despite this, their identification has been based on morphological and then molecular characters in the absence of reference type specimens. Although long of scientific, commercial and regulatory use, these four scientific names are at risk due to a lack of nomenclatural priority. To provide the scientific community with reference voucher samples and to initiate nomenclatural proposals for the recognition of their status as conserved names, three collections from sites mentioned by their authors (Picco and Vittadini) are proposed as epitypes for Tuber aestivum, T. borchii and T. melanosporum, and one as a neotype for T. magnatum. The type of each name is described morphologically and molecularly characterized with the sequences of three markers: ITS, β-tubulin, elongation factor 1α. The taxonomy and nomenclature of each species are discussed. The conservation of the names Tuber aestivum against the previous homonymous Tuber aestivum (Wulfen) Spreng. and the competing name Tuber blotii Eudes-Desl., T. magnatum against Tuber griseum Borch ex Pers., and T. melanosporum against Tuber nigrum Bull. will be proposed. The name Tuber borchii has no previous synonyms and therefore it is legitimate and does not require conservation.
Information about spring ascomycetous fungi on the territory of the nature tract "Kholodnyi Yar" is presented. As the result of the study 33 species of the ascomycetous fungi were identified, 19 of which are actually spring species and 14 – found in the spring. 15 species are registered for the nature tract "Kholodnyi Yar" for the first time. The largest number of species is represented by the family Morchellaceae (5 species), as well as by the families Pezizazeae (4 species) and Sclerotiniaceae (4 species). The ecological-trophic structure is dominated by species with a saprotrophic feeding strategy, which belong to xylotrophs, humus saprotrophs and herbophilic fungi. The group of xylotrophs was the predominant group of saprotrophic fungi in terms of the number of species (10 species). Humus saprotrophs numbered 9 species of the order Pezizales. In addition, representatives of the group of herbophilic (6 species), which use last year's remnants of herbaceous plants as a substrate, were quite common. Dumontinia tuberosa was the most common species among biotrophic species which parasitizes on the rhizomes of plants of the genus Anemone and forms fruiting bodies at the same time as the flowering period of the host plant. Symbiotrophs were represented by 3 species that are also capable of the saprotrophic feeding strategy inherent to humus saprophytes. A new location for Gyromitra slonevskii, Morchella crassipes and M. steppicola – species which were listed in the third edition of the Red Book of Ukraine – has been registered. Species included in the local red lists were also identified, namely Gyromitra gigas and Verpa bohemica (Kyiv region), Helvella acetabulum (Kherson region). The finding of Phylloscypha phyllogena is the second in Ukraine and the first on the territory of the Right-Bank Forest-Steppe.
Understanding features that fostered the persistence of Equisetum–Earth's oldest extant vascular plant genus–since Mesozoic times and through episodes of significant global environmental change, is of current interest in view of modern challenges to plant survival. In addition to known structural and physiological adaptations, we hypothesized that microscopy and shotgun metagenomic sequencing might reveal eukaryotic microorganisms such as fungi that may aid Equisetum survival. Here, we report evidence for several lineages of eukaryotic microbes associated with giant Equisetum xylochaetum, which dominates vegetation in saline streambeds of remote valleys in the hyper-arid Atacama Desert, Chile. Plant material was collected and field-preserved at two comparatively low-disturbance sites; DNA extracted in Chile using low-shear methods was later sequenced, 18S and 28S rDNA taxonomic marker sequences were selected for SILVAngs classification, allowing comparisons to eukaryotic microorganisms previously inferred for earlier-diverging plant lineages. SEM, fluorescence microscopy, and/or LM of toluidine blue-stained sections of roots indicated protists, epiphytic and endophytic fungi, and cortical nematodes. Eukaryotic genera inferred from 18S rDNA at >100X mean sequencing depth included the ciliate Engelmanniella, hyphal chytrid Monoblepharella, predatory ascomycete Cephaliophora, a salpingoecid choanoflagellate, and an annelid worm. 23S rDNA sequences indicated ascomycete Capnodiales fungi at one site and four types of Pezizomycotina fungi at the other. No evidence for vesicular-arbuscular mycorrhizal fungi was found, but we hypothesized that Equisetum may benefit from other types of fungal associations, some possibly inherited from ancestral plant lineages.
Forests have expanded across Europe over the last centuries as a consequence of farmland (agricultural and pasture) abandonment. Agricultural practices usually increase soil fertility and reduce the diversity and abundance of ectomycorrhizal (ECM) fungi, essential mutualists of many woody species in temperate and Mediterranean forests. The recovery of this biotic interaction after the cessation of human activities is, thus, crucial for the re‐establishment of functional forest ecosystems. Here we addressed the legacies of past land use and the recovery of the mutualism between ECM fungi and Fagus sylvatica trees in recent beech forests (< 50 years) in Northeast Spain. Soil and root samples were collected in 6 long‐established and 8 recent beech forests to analyse soil abiotic properties and the ECM fungi associated with beech roots (Illumina DNA metabarcoding of ECM tips). Up to 609 amplicon sequence variants (ASV) of ECM fungi were identified, with 220 ASV found in both forest types. Recent forests had a significantly lower soil organic matter and phosphorus content, which had a significant effect on the community structure of ECM fungi in beech roots. Moreover, beech trees in recent forests interacted with less fungal taxa but had a higher relative abundance of Ascomycota. Tarzetta spp. (Ascomycota, Pezizales) and Lactarius blennius (Basidiomycota, Russulales) emerges as the particular taxa associated with recent and long‐established forests, respectively. More specialized mutualistic networks with a lower species normalized degree were found in recent forests, which might result in a lower quality and resilience of the ectomycorrhizal mutualism. Synthesis: Land‐use history modulated the mycorrhizal symbioses in regenerating beech forests through changes in soil organic matter and nitrogen, which were the main drivers of the differences in fungal community composition and functional types associated with beech trees in recent forests.
We describe two new Japanese truffle species, Tuber iryudaense and Tuber tomentosum, based on molecular and morphological analyses. Both species are clearly distinguishable from other Tuber species by the ocher tomentose mycelium covering the ascoma surfaces. Tuber iryudaense has one-spored asci that each contain a large (68–97 × 51–80 µm), reddish-brown ascospore; these microscopic characters are similar to those of closely related Chinese species, T. calosporum, T. gigantosporum, T. glabrum, T. monosporum, and T. sinomonosporum. Tuber tomentosum forms one to four ascospores per ascus with a reddish-brown color similar to that of ascospores of T. macrosporum and T. canaliculatum, although their spores are much larger than those of T. tomentosum (27‒64 × 26‒55 µm). Molecular phylogenetic analyses based on ribosomal internal transcribed spacer and partial 28S nuc rDNA sequences support that both species are distinct within the Macrosporum group.
Aeolian desertification is the dominant form of land degradation in drylands. The straw checkerboard barrier (SCB) method is effective for sand fixation and has been used to combat aeolian desertification in China. Soil inoculation with ectomycorrhizal (ECM) fungi can help restore degraded lands by improving the soil microbial community and steering plant community development. Combining SCB with afforestation via planting ECM trees and inoculating soil with ECM fungi holds promise for improving plant establishment and growth on shifting sand dunes, but this has yet to be examined. Here, we tested the effects of soil inoculation on ECM colonization of Pinus tabulaeformis roots and the survival and establishment of nursery grown P. tabulaeformis seedlings using three soil treatments: no soil (NS), soil sterilized with fungicide (FPS), and ECM-containing non-treated plantation soil (NPS) collected from a nearby P. tabulaeformis plantation. After two years, P. tabulaeformis survival did not differ among the three soil treatments, but ECM colonization rate, total plant dry weight, and leaf total nitrogen per one seedling in the NPS treatment were 9.0, 2.6, and 3.4 times higher than those in the NS treatment. Water use represented by leaf δ¹³C was also highest in the NPS treatment. Structural equation modeling showed that soil inoculation enhanced ECM colonization of P. tabulaeformis, thus improving nitrogen uptake and water use, leading to increased plant growth. Suillus, Peziza, Geopora, Tuber, and Tomentella were the dominant genera in NPS treatment; 94% of the ECM roots in the NPS treatment were colonized by ECM fungi not detected in NS treatment, indicating that ECM fungi from the inoculum soil were able to colonize the roots of nursery grown seedlings. Only a few ECM fungal species could colonize P. tabulaeformis roots from the plantation soil inoculated, but the taxonomic diversity including Basidiomycota and functional diversity of mycelial exploration types were increased by soil inoculation. These results suggest that soil inoculation with ECM fungi aids in afforestation with ECM plants for the restoration of degraded drylands, including shifting sand dunes.
The South African forestry industry covers approximately 1.3 million hectares and is dependent on exotic pine and eucalypt species. Nursery seedlings are not inoculated with ectomycorrhizal (ECM) fungi. This investigation assessed levels of naturally occurring ECM colonisation of Pinus patula seedlings from 10 different South African forestry nurseries using a grid line intersect method. Fungi from colonised roots were identified using morphological characteristics and Illumina sequencing. Colonisation of seedlings in production nurseries was low (2–21%). Morphologically, the ECM fungi Thelophora terrestris, Suillus sibiricus, and the genera Russula and Pseudotomentella were identified. Molecularly, the ECM fungi T. terrestris, Inocybe jacobi and the genus Sphaerosporella, as well as several other ECM-containing families were identified, along with many saprotrophic/ endophytic fungi belonging to genera such as Penicillium, Ramasonia and Talaromyces. As can be seen, a combination of both molecular and morphological identification techniques are needed as neither is able to give a full picture of the species present in isolation. This study reveals an initial insight into the root microbiome community associated with Pinus patula seedlings, which should be taken into account when inoculation with beneficial microbes is considered. It determined that natural ECM fungal root colonisation levels are very low throughout the South African nurseries investigated, indicating the need for ECM fungal inoculation, which can increase seedling growth, viability and resistance to pathogens.
Majority of the macrofungi are edible/medicinal, while some species are toxigenic causing fatal accidents annually (Wu et al. 2019). Of all the identified fungi in the world, less than 1% are toxigenic (Chang 2008). The poisoning of macrofungi in humans is known since time immemorial and is mentioned in ancient writings like “Rigveda” (at least 3500 B.C.) and “Atharvaveda” (at least 1500 B.C.) (Verma et al. 2014). Avoidance, insufficient knowledge, and misidentification lead to the consumption of toxic macrofungi causing various health hazards, such as vomiting, nausea, stomachache, gastroenteritis, diarrhea, hepatotoxicity, nephrotoxicity, and neurotoxicity, may cause rhabdomyolysis symptoms and erythromelalgia syndrome, and even sometimes lead to mortality (Erguven et al. 2007; Vişneci et al. 2019). Therefore, grasping, preservation, and transmission of ethnomycological knowledge are critical to prevent fungal poisoning or mycetism (Kim and Song 2014). Most of the time, accidental toxicity happens because of misidentification leading to ingestion of toxigenic fungi. The lack of data on toxigenic fungi and information pertaining to toxicological profiles of these fungi contributes more towards their consumption (White et al. 2003; Flesch and Saviuc 2004). Therefore, correct identification of the collected specimens before utilization is prerequisite to avoid toxicity. Some of the common differences usually observed between edible and toxigenic species are given in Table 5.1. Moreover, the national governments in different countries release guidelines and enact legislations for safe commerce and utilization of macrofungi (Peintner et al. 2013).
Fire is a major disturbance linked to the evolutionary history and climate of Mediterranean ecosystems, where the vegetation has evolved fire‐adaptive traits (e.g., serotiny in pines). In Mediterranean forests, mutualistic feedbacks between trees and ectomycorrhizal (ECM) fungi, essential for ecosystem dynamics, might be shaped by recurrent fires. We tested how the structure and function of ECM fungal communities of Pinus pinaster and Pinus halepensis vary among populations subjected to high and low fire recurrence in Mediterranean ecosystems, and analyzed the relative contribution of environmental (climate, soil properties) and tree‐mediated (serotiny) factors. For both pines, local and regional ECM fungal diversity were lower in high than low fire recurrence areas, although certain fungal species were favored in the former. A general decline of ECM root‐tip enzymatic activity for Pinus pinaster was associated with high fire recurrence, but not for Pinus halepensis . Fire recurrence and fire related‐factors such as climate, soil properties or tree phenotype explained these results. In addition to the main influence of climate, the tree fire‐adaptive trait serotiny recovered a great portion of the variation in structure and function of ECM fungal communities associated with fire recurrence. Edaphic conditions (especially pH, tightly linked to bedrock type) were an important driver shaping ECM fungal communities, but mainly at the local scale and likely independently of the fire recurrence. Our results show that ECM fungal community shifts are associated with fire recurrence in fire‐prone dry Mediterranean forests, and reveal complex feedbacks among trees, mutualistic fungi and surrounding environment in these ecosystems.
In Colombia, ectomycorrhizal mushrooms have been collected and documented in several departments and are commonly reported from the native Quercus humboldtii forests. This native species is constrained to the Andean region, occurs within a range of 750–3450 m asl, and establishes mutual symbiotic associations with some fungal genera. In this chapter, we compiled the current state of the art of the ectomycorrhizal mushrooms (ECM) associated with this tropical native oak. We searched reports on the distribution of ectomycorrhizal species associated with Q. humboldtii, and included references where the mycorrhizal status of some fungal genera has been assessed. The family Boletaceae has the highest number of reports, followed by Amanitaceae and Russulaceae. Antioquia has the highest number of reported species, followed by Boyacá and Cundinamarca. Fewer reports are available for the departments of Tolima, Huila, and Quindio, which shows the importance of encouraging studies regarding the taxonomy and recognition of macrofungal diversity, particularly in regions where there is a lack of research in this field. We included 16 local and 2 national records of ECM fungi to the country. Additionally, by searching reports including information on the edibility of wild fungal species, 35 ectomycorrhizal mushrooms are reported as edible to the country.
Species of Tarzetta are morphologically well-defined but their taxonomy is confused because of the multiple interpretations of the oldest names, i.e. T. catinus and T. cupularis. The exploration of this genus with molecular and ecological data gave us the opportunity to partially clarify its taxonomy and to propose typifications of names. The type collections of T. pusilla, T. gaillardiana, and T. spurcata in the sense of Harmaja were reviewed. Hypotarzetta insignis, a semi-hypogeous species, is reinstated in Tarzetta based on molecular data. New species are also described and illustrated: T. gregaria sp. nov. is characterized by its small size and gregarious orangish ascocarps, T. alnicola sp. nov. is a small species associated with alders in riparian woodlands, T. alpina sp. nov. grows in boreo-alpine regions, T. sepultarioides sp. nov. is characterized by its Sepultaria-like appearance and ascus base shape, T. melitensis sp. nov. is a small species described from Malta, and T. quercus-ilicis sp. nov. is a small, sessile species, associated with Quercus ilex in Mediterranean regions. T. betulicola is a provisional name proposed for a species from the T. catinus complex, probably associated with birch trees
Pezizales are a widespread group of fungi, basal to the other filamentous ascomycetes. Most species live in soil as saprobes, in a mycorrhizal relationship with a wide range of plants, or as plant parasites. The lineage Morchellaceae–Discinaceae–Helvellaceae–Tuberaceae includes most of the commercially valuable species in the order. The truffles in the genus Tuber and morels in the genus Morchella arguably command more interest in culinary circles than any other groups of mushrooms. In recent years, the interactions of these fungi with plants have been thoroughly researched although many aspects still need to be clarified. In this chapter, we describe and compare these two groups of mushrooms and take a look at the evidence as to whether there are real trophic differences from those traditionally held and if things are not quite as simple as our forebears would have had us believe. We explore the range of host plants involved in the interactions, the morpho-anatomy of symbiotic structures, the molecular mechanisms of symbiosis, and the influence of other microbial species.
Phylogenetic relationships among ascomycetous truffles and the true and false morels were examined by using sequences from two nuclear encoded ribosomal DNA genes. The data consist of 18S rDNA and partial 28S rDNA sequences for 29 taxa. Individual and combined data sets were analyzed by maximum parsimony (MP), neighbor-joining (NJ) and maximum likelihood (ML) methods. Parsimony analysis of the combined data set, which contained 3 published 18S sequences and consisted of 2358 nucleotide characters, yielded a single most parsimonious tree of 1728 steps. The results indicate that the hypogeous ascomycetous truffle and trufflelike taxa studied represent at least 5 independent lineages within the Pezizales. Results also suggest that several epigeous and most hypogeous taxa have been misplaced taxonomically. Bootstrap analyses show strong support for a Tuberaceae-Helvellaceae clade which is a monophyletic sister group of a Morchellaceae-Discinaceae clade. Rhizina is a sister group to both of these clades in the MP and ML trees while in the NJ tree it is a sister of the Morchellaceae-Discinaceae clade. MP, ML, and NJ tree topologies indicate that Rhizina should be removed from the Helvellaceae and classified in a monotypic family, the Rhizinaceae. A phylogenetically-based classification for these fungi is proposed together with emendations of 4 families.
The authors used molecular techniques to examine the ectomycorrhizal fungal community associated with pinyon pine (Pinus edulis) growing in two soil types in a semiarid region of northern Arizona. Pinyon performance (e.g., growth, reproduction, water stress) has been shown to be markedly lower in cinder than in sandy-loam environments. Fungal community composition and richness were determined using RFLP (restriction fragment length polymorphism) analysis of ectomycorrhizal root tips collected from three sites within each soil type. Several patterns emerged from these analyses. First, communities in both cinder and sandy-loam soils were dominated by one or a few abundant ectomytcorrhizal types, a species abundance pattern common to many plant and animal communities. Second, unlike the pattern for many other organisms, ectomycorrhizal fungal type richness was not correlated with measures of ecosystem productivity such as soil nutrient and moisture levels; cinder and sandy-loam soils had similar numbers of ectomycorrhizal fungal types. Third, soil type and fungal community composition were linked, as cluster analysis demonstrated greater similarity of fungal communities from sites within soil types than between them. Fourth, a preliminary survey of 14--45 ectomycorrhizal root tips from each of 20 trees at one cinder site indicated that trees were dominated by one or a few ectomycorrhizal RFLP types. Fifth, the RFLP patterns of some fungal sporocarps matched those of ectomycorrhizal root tips, but many did not, indicating that many of the ectomycorrhizal fungi at these sites fruit infrequently, whereas other fungi with more abundant sporocarps may not form ectomycorrhiza.
This is the one essential handbook for all who work with or are interested in fungi (including lichens, slime moulds, yeasts and fungal analogues).This new edition, with more than 21,000 entries, provides the most complete listing available of generic names of fungi, their families and orders, their attributes and descriptive terms. For each genus, the authority, the date of publication, status, systematic position, number of accepted species, distribution, and key references are given. Diagnoses of families and details of orders and higher categories are included for all groups of fungi. In addition, there are biographic notes, information on well-known metabolites and mycotoxins, and concise accounts of almost all pure and applied aspects of the subject (including citations of important literature).All information has been updated as necessary since the publication of the ninth edition in 2001. In addition the tenth edition has the following new features: a completely new classification of the Kingdom Fungi based on recent multi-gene phylogenetics research; a major revision of the classification of the Basidiomycota and substantial modification of the "basal" groups; further integration of anamorphic and teleomorphic genera in the classification; enhanced distinctions between the true fungi and unrelated groups traditionally studied by mycologists; and, improved information on references to publications.
Morphological and molecular (polymerase chain reaction - restriction fragment length polymorphism) methods were used to assess ectomycorrhiza (ECM) diversity in naturally regenerating and planted Picea engelmannii Parry ex Engelm. ◊ Picea glauca (Moench) Voss seedlings in two recently clear-cut sites, two clear-cut and broadcast burned sites, and two mature forests (>100 years) in central British Columbia. Based on 24 characterized ECM, burning did not affect overall diversity (Shannon, Simpson, Shannon evenness, and Margalef indices). However, the occurrence and relative abundance of some ECM morphotypes varied significantly. Hebeloma and a Russulaceae type 1 were more abundant and Cenococcum was less abundant in planted seedlings from cut-burned sites compared with those from clear-cut sites. E- strain, MRA, and Amphinema were more abundant in planted seedlings from both cut-burned and clear-cut sites com- pared with naturally regenerating seedlings from mature sites. ECM diversity of regenerating seedlings was significantly greater in mature forests compared with clear-cut sites and was greater in planted seedlings than naturally regenerating seedlings in clear-cut sites. Molecular analysis of the internal transcribed spacer region of the nuclear-encoded ribosomal RNA gene repeat showed no significant differences among treatments or seedling type. Twenty-two genotypes were identi- fied from eight common morphotypes: Cenococcum (one), Thelephora (two), E-strain, Tuber, Hebeloma, and Russulaceae type 1 (three each), MRA (four), and Amphinema (six). Hebeloma genotypes matched three for Amphinema; genotypes from unidentified lightly colonized tips matched those for E-strain, MRA, and Amphinema-Hebeloma.
Nuclear-encoded ribosomal RNA gene sequences (rDNA) spanning 107 base pairs at the 3′ end of the 18S gene, the 5′ internal transcribed spacer region (ITS1), and across divergent domain D1 near the 5′ end of the 28S gene were analyzed to infer a phylogeny for taxa of the E-strain mycorrhizal fungal genus Wilcoxina and to determine their relationship to representatives of the genus Tricharina. The phylogeny suggests that Wilcoxina and Tricharina, although related, should be maintained as separate genera. Wilcoxina taxa formed a distinct group that exhibited interspecific variation of 37.6% in the ITS1 region. Wilcoxina alaskana was the most distant taxon, which is consistent with its growth on an unusual substrate (rotting wood). It remains to be confirmed that this taxon is mycorrhizal. A cryptic Wilcoxina species, known only from root isolates, was found. Sequence analysis of the ITS1 region distinguished two varieties of Wilcoxina mikolae: var. mikolae and var. tetraspora. Among the taxa of Tricharina examined there was 31.2% variation in the ITS1 region. The most divergent taxon in the Tricharina group was Tricharina praecox, although sequence analysis was unable to distinguish the varieties described within this species. The remaining taxa in Tricharina formed a tight group with only 10.2% interspecific divergence in the ITS1 region. There is sequence evidence that at least two taxa are included in Tricharina gilva as presently delineated. As the sole report of mycorrhiza formation in Tricharina is shown to be based upon a misidentification, it therefore appears that only Wilcoxina taxa are mycorrhizal. Keywords: E-strain, Wilcoxina, Tricharina, mycorrhiza, ribosomal DNA, phylogeny.
Twenty-two species of postfire ascomycetes belonging to the order Pezizales were screened for biotrophic interactions with roots of lodgepole pine (Pinus contorta Dougl.). Biotrophic associations ranged from pathogenicity to mycorrhizal symbiosis, but most species tested did not show any affinity for roots. Pyropyxis rubra (Peck) Egger and Rhizina undulata Fr. were aggressive pathogens that infected the vascular cylinder and killed the seedlings. Tricharina praecox (Karst.) Dennis var. intermedia Egger, Yang & Korf also had some ability to infect the vascular cylinder, but usually did not kill the seedlings. Geopyxis carbonaria (A. & S.) Sacc. and Trichophaea hemisphaerioides (Mont.) Graddon invaded the cortex, forming complex intracellular structures, but did not penetrate the vascular cylinder. They may form mutualistic associations under certain conditions. The only confirmed mutualistic species was Sphaerosporella brunnea (A. & S.) Svrcek & Kubicka, which formed ectendomycorrhizae. Anthracobia maurilabra (Cooke) Boud. and A. tristis (Bomm., Rouss. & Sacc.) Boud. appear to be primarily root-surface inhabitants with limited capacity to infect cortical tissues through breaks in the epidermis. Gyromitra infula (Schaef.) Quél. penetrated the epidermis but was unable to overcome host defences against pathogenic infection.
Phylogenetic analyses of partial SSU rDNA sequences from representatives of 36 pezizales associated genera are presented, including new sequences from 28 species: Aleuria aurantiaca, Ascodesmis sphaerospora, Boudiera acanthospora, Caloscypha fulgens, Cheilymenia stercorea, Cookeina sulcipes, Desmazierella acicola, Geopyxis carbonaria, Hydnotrya tulasnei, Iodophanus carneus, Microstoma protracta, Otidea leporina, Paurocotylis pila, Peziza succosa and P vesiculosa (the type species of the family Pezizaceae and the order Pezizales), Pyronema domesticum, Pulvinula archeri, Saccobolus sp., Sarcoscypha austriaca, Sarcosoma globosum, Sarcosphaera coronaria, Scutellinia scutellata and S. torrentis, Sphaerosporella brunnea, Tarzetta catinus, Thelebolus crustaceus, Trichophaea hybrida, Trichophaeopsis bicuspis, and Wilcoxina mikolae. Two taxon and character matrices were subjected to maximum parsimony, maximum likelihood, and neighbor-joining analyses. The first matrix included 28 taxa and a full character set of 1600 bp, and the second matrix 37 taxa and a restricted set of 1053 characters. The analyses using the restricted character set generally yielded the same topology as the full character set but the resolution was reduced. Three main evolutionary lineages were detected within the order: (1) Pezizaceae and Ascobolaceae, (2) Helvellaceae, Morchellaceae, Tuberaceae, and Caloscypha (Otideaceae), and (3) Sarcoscyphaceae, Sarcosomataceae, Ascodes-midaceae, Glaziellaceae, Otideaceae and Pyronemataceae. The inferred subordinal grouping is compared to extant classification schemes of the Pezizales. Sarcosomataceae and Sarcoscyphaceae are recognized as separate monophyletic groups. The analyses did not support recognition of Pyronemataceae, Ascodesmida-ceae, and Glaziellaceae as separate from the Otideaceae. Thelebolus (Thelebolaceae) clusters with extra-pezizalean genera and does not belong to the order.
1 The effects of wildfire ash on ectomycorrhizal (EM) associations were investigated by sampling bishop pine (Pinus muricata, D. Don) seedlings from control and ash-removed plots 1.5 years after a severe fire in a northern Californian P. muricata forest. The below-ground community composition of EM at the site was characterized using molecular techniques (PCR-RFLP and nucleotide sequencing).
2 A total of 30 fungal taxa were observed, many of which differed in their distribution between treatment and control seedlings. However, most of the taxa that were distinctive to either treatment or control seedlings occurred only once across the site, precluding statistical detection of potential ash effects on EM community composition. There were no significant effects of ash removal on plot-level mycorrhizal community richness or diversity, and there were no distinct treatment-related clusters in a principal components analysis.
3 Analysis of the combined data indicated that numbers of fungal taxa per seedling, numbers of successive root depth increments colonized by the same taxon, and distances to neighbouring seedlings colonized by the same taxon, were randomly distributed across the site for the majority of mycorrhizal fungi. These distributional patterns suggest that the post-fire mycorrhizal community structure on P. muricata arose primarily from successful colonization by randomly distributed point-source fungal inocula within the upper mineral soil layer of the forest floor.
4 By comparison with pre-fire studies from similar P. muricata sites nearby, our data indicate that severe wildfire disturbance resulted in marked changes in mycorrhizal community composition, and a sharp increase in the relative biomass of ascomycetous fungi.
The mycobionts of Piceirhiza bicolorata, a distinct ectomycorrhizal morphotype of conifers and hardwoods, have been identified by internal transcribed spacer 1 (ITS1) nuclear ribosomal DNA (rDNA) sequence comparison of the fungi involved. Samples of Piceirhiza bicolorata were obtained from seedlings of Picea abies, Pinus sylvestris, Betula pubescens, Populus tremula, Quercus robur and Salix phylicifolia. In an initial screening, the fungus amplified with universal ITS primers from ectomycorrhizal root samples of P. bicolorata shared approx. 95% ITS1 sequence identity with the ericoid mycorrhizal fungus Hymenoscyphus ericae. A total of 77 out of 88 (= 87.5%) DNA samples (i.e. 52/56 root samples and 25/32 axenic culture isolates) of P. bicolorata were successfully amplified with a taxon-selective primer designed for exclusive amplification of H. ericae-like strains. Forty-seven amplicons were sequenced, yielding 15 different ITS1 genotypes that differed by 1–14 nucleotide character state changes. An inferred ITS1 phylogeny (maximum parsimony) showed that a single major evolutionary lineage of P. bicolorata embraced the historically important H. ericae isolates in a 100% bootstrap-supported clade. The 15 P. bicolorata genotypes were positioned in four subclades, roughly corresponding to morphological groups of P. bicolorata isolates observed in axenic culture. Culture isolates of H. ericae and P. bicolorata share some common morphological features including slow, dense growth and formation of short aerial hyphal aggregates. Our results suggest that members of the H. ericae aggregate participate in the formation of the distinct ectomycorrhizal morphotype P. bicolorata. This opposes the widely accepted discrimination of ericoid and ectomycorrhizal mycobionts of the boreal forest ecosystem. The high prevalence of the P. bicolorata morphotype on pioneer seedlings of P. sylvestris, B. pubescens and S. phylicifolia at a copper mine spoil was remarkable. Hypotheses of possible nutrient mobilization and detoxification potentials of the fungal associates of P. bicolorata are discussed. We hypothesize that ericoid and ectomycorrhizal plants may share mycobionts of the H. ericae aggregate.
Molecular tools have now been applied for the past 5 years to dissect ectomycorrhizal (EM) community structure, and they have propelled a resurgence in interest in the field. Results from these studies have revealed that: (i) EM communities are impressively diverse and are patchily distributed at a fine scale below ground; (ii) there is a poor correspondence between fungi that appear dominant as sporocarps vs. those that appear dominant on roots; (iii) members of Russulaceae, Thelephoraceae, and/or non-thelephoroid resupinates are among the most abundant EM taxa in ecosystems sampled to date; (iv) dissimilar plants are associated with many of the same EM species when their roots intermingle — this occurs on a small enough spatial scale that fungal individuals are likely to be shared by dissimilar plants; and (v) mycoheterotrophic plants have highly specific fungal associations. Although, these results have been impressive, they have been tempered by sampling difficulties and limited by the taxonomic resolution of restriction fragment length polymorphism methods. Minor modifications of the sampling schemes, and more use of direct sequencing, has the potential to solve these problems. Use of additional methods, such as in situ hybridization to ribosomal RNA or hybridization coupled to microarrays, are necessary to open up the analysis of the mycelial component of community structure.
Mycorrhizal symbioses are widespread mutualistic associations of many plant hosts found in many habitats. One type of putative mycorrhizal association, ectendomycorrhiza, is confined to Pinus and Larix spp. and is common in conifer nurseries and in disturbed habitats. This association is characterized by the unique combination of a fungal mantle, Hartig net, and intracellular hyphae, the latter forming soon after Hartig net development. Many reports of the occurrence of ectendomycorrhizas from field-collected specimens are likely erroneous and instead may represent senescent ectomycorrhizas. The fungus species involved in the formation of ectendomycorrhizas were initially called E-strain fungi and their identification was based on characteristics of hyphae and chlamydospores. With the discovery of teleomorphs for some of these fungi, they were found to be ascomycetes. More recently, molecular methods have been used to clarify their systematics and phylogeny and it is apparent that most of the isolates belong to two species, Wilcoxina mikolae and Wilcoxina rehmii. Two species of dematiaceous fungi and a member of the Pezizales, Sphaerosporella brunnea, also have been reported to form ectendomycorrhizas. These fungi can form ectendomycorrhizas with their hosts over a broad pH range and may utilize many substrates as a carbon source. Ectendomycorrhizas may be important in the revegetation of disturbed sites and in the establishment of conifer seedlings in post-fire situations.
The carbonicolous discomycete, Sphaerosporella brunnea, formed ectomycorrhizae with jack pine (Pinus banksiana) in monoxenic cultures and in open containers. In addition, mycorrhizae were formed with species of Picea, Larix, and Populus. The mycorrhizae were characterized by thin mantles and large diameter hyphal cells with Woronin bodies at the septa. Sphaerosporella brunnea is unusual as a mycorrhizal symbiont due to its taxonomic position, carbonicolous nature, very rapid growth rate, and ease of ascospore germination.
Locations of epigeous basidiocarps of five common ectomycorrhizal fungi with substantial spore deposits beneath them and of two hypogeous species were marked in the fall. Subsamples of the litter and mineral soil at 0- to 3- and 3- to 6-cm depths were subsequently taken with a soil corer from locations marked for epigeous basidiocarps, and extracted in the fall and again following snowmelt with a procedure developed to enumerate propagules of ectomycorrhizal fungi from the soil. Spores of most epigeous species were plentiful in the litter layer in the fall but were much less abundant in the spring. Spores of Suillus brevipes, Suillus tomentosus and Lactarius scrobiculatus were still present at the 0- to 3-cm depth in the spring. No spores of any of the epigeous fungi were found at the 3- to 6-cm depth in the spring. Subsamples of mineral soil were also taken in the spring at locations marked for the hypogeous fungi. Spores of both Rhizopogon subcaerulescens and Rhizopogon rubescens were present in high numbers in the lowermost soil fractions after snowmelt. In a second study sclerotia of two species of fungi were extracted from soil in a burned area and a nearby unburned forest for 2 years following fire. Sclerotia of Cenococcum geophilum and a species of Morchella were more numerous in the burn than in the unburned forest in both years. Both basidiospores and sclerotia persisted in the soil for at least 2 years. Basidiospores of hypogeous fungi appear to persist in the soil for longer periods than those of epigeous fungi due to in situ dispersion deeper into the soil profile. Although maximum longevity of spores in the soil has not been determined, observed differential persistence of spores from epigeous and hypogeous ectomycorrhizal fungi could play a role in soil mycorrhiza-forming potential and population dynamics of ectomycorrhizal fungi.
The occurrence of 93 species of soil inhabiting Pezizales was studied on the basis of 699 site descriptions and soil samples, the latter analyzed for 15 edaphic variables. For species represented by 10 samples or more, the median value of each of the edaphic variables is given, and the range of pH, water soluble Al, CaCO3, and 0.2 N H2SO4–soluble P. For species represented by from 5 to 9 samples the range of pH and organic matter is given. 13 habitat types are described. The verges of forest roads proved to be the most important habitat type (247 sites, 57 species). The distribution in Denmark of 20 common species is compared with the geographical variation in quaternary and prequaternary geology, and with the distribution of soil types. It is concluded that the importance in the investigation area of disturbed ground as a habitat for soil inhabiting Pezizales is due to unleached mineral soil being brought to the surface, creating edaphic conditions favourable to a large number of species. – Although it is impossible, on the basis of the present investigation, to state definitively whether one or more edaphic variables are of particular importance in determining the occurrence of the species, there are certain indications that pH – and in some cases organic matter – are of special significance. A grouping of the species into five ecological groups on the basis of the median value of pH and organic matter is proposed. The habitats of soil inhabiting Pezizales in the investigation area and in other parts of the world are compared.
Ectomycorrhizal (ECM) fungi are widespread plant root symbionts in boreal forests, but information is lacking on the fine scale distribution of roots and fungi in substrate patches of different quality, including coarse woody debris (CWD). Wood and soil cores were taken systematically both horizontally and vertically through decayed logs and underlying soil layers in a mixed forest. Root tips were counted and ECM fungi identified by morphotyping and sequencing. The abundance of root tips and ECM fungi was highly variable on a 5-cm scale. Most species were replaced on a 50-cm scale. Detrended correspondence analysis demonstrated strong preference of resupinate thelephoroid and athelioid fungi and Sebacinaceae for CWD, whereas ascomycetes and euagarics appeared more frequently in mineral soil. Clavulicium delectabile was determined to be an ECM fungus for the first time. ECM fungi occupy different niches and show variable distribution patterns. CWD plays an important role as a habitat both for roots and ECM fungi. We suggest sampling larger soil cores and selecting random root tips in future studies. Sequencing is a powerful tool in ECM community studies.
Coming back to Paris was an emotional experience for me, because it was 45 years ago as a graduate student I came on a pilgrimage to meet one of the most influential of people who have ever worked with discomycetes, Mme Marcelle LeGal. She greeted me and treated me with the kind of courtesy and interest that I hope all of us can express towards those who come green and wanting to learn. It was an experience I will never forget, and one which led me in future years to propose a genus Galiella in her honour, and to copropose Marcellina also in her honour, and on whose back many of us stand today. The other great figure of that period on whose contributions much of our classification lies is Jan A. Nannfeldt, another mycologist I met that same year in Uppsala where I went to meet and learn from him.
A current list of ectomycorrhizae-forming Ascomycota and their respective hosts is provided. Three orders, Elaphomycetales, Leotiales and Pezizales, are represented by 14 families containing 42 genera (two anamorphs) and more than 100 species. References on Ascomycota and host species suspected of being in mycorrhizal association are also presented.
Some of the most revolutionary changes in the systematics of various divisions of algae and certain classes of fungi were the results of unique differences found in the ultrastructure of septa. Among the fungi, septal ultrastructure has played a significant role in helping to delineate classes and subclasses of basidiomycetes. The application of septal ultrastructure to ascomycete systematics has been limited. Yet, there are strikingly different types of septal pore organelles in various groups of ascomycetes. This presentation demonstrates that septal structures may be useful in delimiting various groups of ascomycetes. The major focus is on septal structures associated with asci, ascogenous hyphae, and excipular cells of families of Pezizales. The use of these characters to show phylogenetic linkages between the epigeous and hypogeous tuberalean Pezizales is demonstrated. Septa as taxonomic criteria in other groups of ascomycetes are also discussed.
A morphological and anatomical study of the mycorrhizas on Pinus strobus L. was conducted on seedlings excavated from St.-Williams nursery in southern Ontario. Micro- and macro-scopic characters were used to classify the morphotypes into complexes and, when possible, genera and species. An E-strain fungus, fungi from the Mycelium radicis atrovirens (MRA) complex, and an unidentified ascomycetous 'red-type' fungus formed ectendomycorrhizal (EECM) associations, while Tuber sp., Hebeloma sp., and Thelephora terrestris formed ectomycorrhizal (ECM) associations in the nursery. Cultures of Hebeloma sp., the E-strain fungus, Tuber sp., and two morphologically distinct MRA fungi (MRA1, later identified as Phialophora finlandia Wang and Wilcox, and MRA2, unidentified) were isolated from field-collected morphotypes and re-inoculated onto Pinus strobus seedlings grown in semisterile pot cultures for 4 months. In the resynthesis experiment, the E-strain fungus formed EECM with sparse intracellular colonization, and Tuber sp. formed ECM with characteristic cystidia and densely packed mantles, as they had in the field. However, unlike the MRA field specimens, Phialophora finlandia formed ECM in pot culture. Hebeloma sp., normally an ECM former with conifer seedlings, did not form mycorrhizal structures under the given culture conditions, and neither did the MRA2 isolate.
Publisher Summary This chapter discusses the characterization of ectomycorrhiza. Ectomycorrhiza structures consist of fungal tissues, the arrangement and organization of which can be used to describe fungal species in the same way as any other taxonomically suitable feature. Their characteristics are well conserved. Furthermore, it has been shown that some ectomycorrhizal fungi can grow their hyphae within the rhizomorphs and ectomycorrhiza of other fungi, suggesting that ectomycorrhizal fungi can influence each other with respect to plant nutrition and with respect to their fruit body formation. All ectomycorrhiza regarded as being of one species and one sample must be checked for homogeneity. To do this a few tips should be carefully compared both morphologically and anatomically using rhizomorph and mantle preparations. The chapter also discusses preparations of ectomycorrhiza with morphological characterization, color photography, and autofluorescence. The ectomycorrhiza are photographed in water to allow emanating hyphae and rhizomorphs to spread out into approximately their natural position. The ectomycorrhizal system can be held in forceps which in turn are held by a clamp. There is also a description of anatomical characterization in the chapter.
The carbonicolous discomycete, Sphaerosporella brunnea, formed ectomycorrhizae with jack pine (Pinus banksiana) in monoxenic cultures and in open containers. In addition, mycorrhizae were formed with species of Picea, Larix, and Populus. The mycorrhizae were characterized by thin mantles and large diameter hyphal cells with Woronin bodies at the septa. Sphaerosporella brunnea is unusual as a mycorrhizal symbiont due to its taxonomic position, carbonicolous nature, very rapid growth rate, and ease of ascospore germination.
— We studied sequence variation in 16S rDNA in 204 individuals from 37 populations of the land snail Candidula unifasciata (Poiret 1801) across the core species range in France, Switzerland, and Germany. Phylogeographic, nested clade, and coalescence analyses were used to elucidate the species evolutionary history. The study revealed the presence of two major evolutionary lineages that evolved in separate refuges in southeast France as result of previous fragmentation during the Pleistocene. Applying a recent extension of the nested clade analysis (Templeton 2001), we inferred that range expansions along river valleys in independent corridors to the north led eventually to a secondary contact zone of the major clades around the Geneva Basin. There is evidence supporting the idea that the formation of the secondary contact zone and the colonization of Germany might be postglacial events. The phylogeographic history inferred for C. unifasciata differs from general biogeographic patterns of postglacial colonization previously identified for other taxa, and it might represent a common model for species with restricted dispersal.
The occurrence of 93 species of soil inhabiting Pezizales was studied on the basis of 699 site descriptions and soil samples, the latter analyzed for 15 edaphic variables. For species represented by 10 samples or more, the median value of each of the edaphic variables is given, and the range of pH, water soluble Al, CaCO3, and 0.2 N H2SO4-soluble P. For species represented by from 5 to 9 samples the range of pH and organic matter is given. 13 habitat types are described. The verges of forest roads proved to be the most important habitat type (247 sites, 57 species). The distribution in Denmark of 20 common species is compared with the geographical variation in quaternary and prequaternary geology, and with the distribution of soil types. It is concluded that the importance in the investigation area of disturbed ground as a habitat for soil inhabiting Pezizales is due to unleached mineral soil being brought to the surface, creating edaphic conditions favourable to a large number of species. - Although it is impossible, on the basis of the present investigation, to state definitively whether one or more edaphic variables are of particular importance in determining the occurrence of the species, there are certain indications that pH - and in some cases organic matter - are of special significance. A grouping of the species into five ecological groups on the basis of the median value of pH and organic matter is proposed. The habitats of soil inhabiting Pezizales in the investigation area and in other parts of the world are compared.
Four types of ascomycete mycorrhizas were found on seedlings of Abies alba grown in pot cultures on mineral soil. One type was formed by Cenococcum graniforme Ferd. & Winge; the fungal partners of the other three types could not be identified. The macroscopic and microscopic characteristics are described. One mycorrhiza appeared to be identical with Type 15 of Haug & Oberwinkler, found in natural spruce stands. Senescent stages of this type are also described. Ultrastructural investigations showed that the dolipore seemed to be the main distinguishing feature between ascomycete and basidiomycete mycorrhizas. Differences in the matrix of the interface and the fungal wall were not stable enough to be used as a distinguishing feature between asco- and basidiomycetes. Dead fungal cells were isolated from the living tissue by plugging of septa with Woronin bodies and walling-over of the plugged septa. Subsequently these isolated dead cells could be colonized by the fungus. The predominant mycorrhization of the fir seedlings by ascomycetes in pot culture with mineral soil is discussed.