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Christian Brunold - One of the best experts on this subject based on the ideXlab platform.
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effects of cadmium on non mycorrhizal and mycorrhizal norway spruce seedlings picea abies l karst and its ectomycorrhizal fungus Laccaria laccata scop ex fr bk br sulphate reduction thiols and distribution of the heavy metal
New Phytologist, 1993Co-Authors: Ulrich Galli, Martin Meier, Christian BrunoldAbstract:SUMMARY The effect of cadmium on assimilatory sulphate reduction and thiol content was studied in non-mycorrhizal and mycorrhizal Norway spruce seedlings (Picea abies) and its ectomycorrhtzal fungus Laccaria laccata. The distribution of cadmium was also investigated. Isotope dilution experiments indicated that the fungus reduced sulphate via adenosine 3′-phosphate 5′-phosphosulphate sulphotransferase, whereas Norway spruce seedlings assimilated sulphate via adenosine 5′-phosphosulphate sulphotransferase in both roots and needles. In mycorrhizal roots only the plant sulphotransferase activity could be measured. Mycorrhizal and non-mycorrhizal roots and the mycelium of Laccaria laccata contained increased activities of sulphotransferase and more acid-soluble thiols when cultivated with cadmium. The increase in acid-soluble thiols was due to phytochelatins in roots and to glutathione in Laccaria laccata, where neither phytochelatins nor metallothioneins could be detected. Even though the cadmium content of mycorrhizal roots was slightly higher than that of non-mycorrhizal roots, concentrations of phytochelatin were only half as high as in non-mycorrhizal roots. Cadmium content of needles of mycorrhizal plants was significantly lower than that of non-mycorrhizal plants. Most of the cadmium in Laccaria laccata was associated with the cell walls and could be exchanged with Ni2+.
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Effects of cadmium on non‐mycorrhizal and mycorrhizal Norway spruce seedlings [Picea abies (L.) Karst.] and its ectomycorrhizal fungus Laccaria laccata (Scop, ex Fr.) Bk. & Br.: Sulphate reduction, thiols and distribution of the heavy metal
New Phytologist, 1993Co-Authors: Ulrich Galli, Martin Meier, Christian BrunoldAbstract:SUMMARY The effect of cadmium on assimilatory sulphate reduction and thiol content was studied in non-mycorrhizal and mycorrhizal Norway spruce seedlings (Picea abies) and its ectomycorrhtzal fungus Laccaria laccata. The distribution of cadmium was also investigated. Isotope dilution experiments indicated that the fungus reduced sulphate via adenosine 3′-phosphate 5′-phosphosulphate sulphotransferase, whereas Norway spruce seedlings assimilated sulphate via adenosine 5′-phosphosulphate sulphotransferase in both roots and needles. In mycorrhizal roots only the plant sulphotransferase activity could be measured. Mycorrhizal and non-mycorrhizal roots and the mycelium of Laccaria laccata contained increased activities of sulphotransferase and more acid-soluble thiols when cultivated with cadmium. The increase in acid-soluble thiols was due to phytochelatins in roots and to glutathione in Laccaria laccata, where neither phytochelatins nor metallothioneins could be detected. Even though the cadmium content of mycorrhizal roots was slightly higher than that of non-mycorrhizal roots, concentrations of phytochelatin were only half as high as in non-mycorrhizal roots. Cadmium content of needles of mycorrhizal plants was significantly lower than that of non-mycorrhizal plants. Most of the cadmium in Laccaria laccata was associated with the cell walls and could be exchanged with Ni2+.
Taizo Hogetsu - One of the best experts on this subject based on the ideXlab platform.
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Genet dynamics and ecological functions of the pioneer ectomycorrhizal fungi Laccaria amethystina and Laccaria laccata in a volcanic desert on Mount Fuji.
Mycorrhiza, 2014Co-Authors: Abdul Wadud, Kazuhide Nara, Chunlan Lian, Takahide A. Ishida, Taizo HogetsuAbstract:To understand the reproduction of the pioneer ectomycorrhizal fungi Laccaria amethystina and Laccaria laccata in a volcanic desert on Mount Fuji, Japan, the in situ genet dynamics of sporocarps were analysed. Sporocarps of the two Laccaria species were sampled at fine and large scales for 3 and 2 consecutive years, respectively, and were genotyped using microsatellite markers. In the fine-scale analysis, we found many small genets, the majority of which appeared and disappeared annually. The high densities and annual renewal of Laccaria genets indicate frequent turnover by sexual reproduction via spores. In the large-scale analysis, we found positive spatial autocorrelations in the shortest distance class. An allele-clustering analysis also showed that several alleles were distributed in only a small, localised region. These results indicate that Laccaria spores contributing to sexual reproduction may be dispersed only short distances from sporocarps that would have themselves been established via rare, long-distance spore dispersal. This combination of rare, long-distance and frequent, short-distance Laccaria spore dispersal is reflected in the establishment pattern of seeds of their host, Salix reinii.
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development of microsatellite markers from an ectomycorrhizal fungus Laccaria amethystina by a dual suppression pcr technique
Molecular Ecology Notes, 2006Co-Authors: M. A. Wadud, Kazuhide Nara, Chunlan Lian, Takahide A. Ishida, Taizo HogetsuAbstract:Laccaria amethystina is a major early successional ectomycorrhizal fungus. We isolated 10 polymorphic loci from L. amethystina using a dual-suppression-PCR (polymerase chain reaction) technique. These loci provided microsatellite markers with polymorphism of two to 10 alleles per locus. The observed and expected heterozygosities ranged from 0.136 to 0.545 and 0.206 to 0.877, respectively.
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Development of microsatellite markers from an ectomycorrhizal fungus, Laccaria amethystina, by a dual‐suppression‐PCR technique
Molecular Ecology Notes, 2006Co-Authors: M. A. Wadud, Kazuhide Nara, Chunlan Lian, Takahide A. Ishida, Taizo HogetsuAbstract:Laccaria amethystina is a major early successional ectomycorrhizal fungus. We isolated 10 polymorphic loci from L. amethystina using a dual-suppression-PCR (polymerase chain reaction) technique. These loci provided microsatellite markers with polymorphism of two to 10 alleles per locus. The observed and expected heterozygosities ranged from 0.136 to 0.545 and 0.206 to 0.877, respectively.
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Isolation and characterization of five microsatellite loci in an ectomycorrhizal fungus Laccaria laccata
Molecular Ecology Notes, 2006Co-Authors: M. A. Wadud, Kazuhide Nara, Chunlan Lian, Taizo HogetsuAbstract:Laccaria laccata is an early successional ectomycorrhizal fungus. We isolated five polymorphic microsatellite loci from L. laccata using a dual-suppression polymerase chain reaction technique. The number of alleles per locus ranged from three to six. The observed and expected heterozygosities ranged from 0.269 to 0.462, and 0.249 to 0.775, respectively. These microsatellite markers would be valuable molecular tools for population genetic studies of L. laccata.
Ulrich Galli - One of the best experts on this subject based on the ideXlab platform.
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effects of cadmium on non mycorrhizal and mycorrhizal norway spruce seedlings picea abies l karst and its ectomycorrhizal fungus Laccaria laccata scop ex fr bk br sulphate reduction thiols and distribution of the heavy metal
New Phytologist, 1993Co-Authors: Ulrich Galli, Martin Meier, Christian BrunoldAbstract:SUMMARY The effect of cadmium on assimilatory sulphate reduction and thiol content was studied in non-mycorrhizal and mycorrhizal Norway spruce seedlings (Picea abies) and its ectomycorrhtzal fungus Laccaria laccata. The distribution of cadmium was also investigated. Isotope dilution experiments indicated that the fungus reduced sulphate via adenosine 3′-phosphate 5′-phosphosulphate sulphotransferase, whereas Norway spruce seedlings assimilated sulphate via adenosine 5′-phosphosulphate sulphotransferase in both roots and needles. In mycorrhizal roots only the plant sulphotransferase activity could be measured. Mycorrhizal and non-mycorrhizal roots and the mycelium of Laccaria laccata contained increased activities of sulphotransferase and more acid-soluble thiols when cultivated with cadmium. The increase in acid-soluble thiols was due to phytochelatins in roots and to glutathione in Laccaria laccata, where neither phytochelatins nor metallothioneins could be detected. Even though the cadmium content of mycorrhizal roots was slightly higher than that of non-mycorrhizal roots, concentrations of phytochelatin were only half as high as in non-mycorrhizal roots. Cadmium content of needles of mycorrhizal plants was significantly lower than that of non-mycorrhizal plants. Most of the cadmium in Laccaria laccata was associated with the cell walls and could be exchanged with Ni2+.
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Effects of cadmium on non‐mycorrhizal and mycorrhizal Norway spruce seedlings [Picea abies (L.) Karst.] and its ectomycorrhizal fungus Laccaria laccata (Scop, ex Fr.) Bk. & Br.: Sulphate reduction, thiols and distribution of the heavy metal
New Phytologist, 1993Co-Authors: Ulrich Galli, Martin Meier, Christian BrunoldAbstract:SUMMARY The effect of cadmium on assimilatory sulphate reduction and thiol content was studied in non-mycorrhizal and mycorrhizal Norway spruce seedlings (Picea abies) and its ectomycorrhtzal fungus Laccaria laccata. The distribution of cadmium was also investigated. Isotope dilution experiments indicated that the fungus reduced sulphate via adenosine 3′-phosphate 5′-phosphosulphate sulphotransferase, whereas Norway spruce seedlings assimilated sulphate via adenosine 5′-phosphosulphate sulphotransferase in both roots and needles. In mycorrhizal roots only the plant sulphotransferase activity could be measured. Mycorrhizal and non-mycorrhizal roots and the mycelium of Laccaria laccata contained increased activities of sulphotransferase and more acid-soluble thiols when cultivated with cadmium. The increase in acid-soluble thiols was due to phytochelatins in roots and to glutathione in Laccaria laccata, where neither phytochelatins nor metallothioneins could be detected. Even though the cadmium content of mycorrhizal roots was slightly higher than that of non-mycorrhizal roots, concentrations of phytochelatin were only half as high as in non-mycorrhizal roots. Cadmium content of needles of mycorrhizal plants was significantly lower than that of non-mycorrhizal plants. Most of the cadmium in Laccaria laccata was associated with the cell walls and could be exchanged with Ni2+.
Francis Martin - One of the best experts on this subject based on the ideXlab platform.
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Expanding genomics of mycorrhizal symbiosis
Frontiers in Microbiology, 2014Co-Authors: Alan Kuo, Francis Martin, Annegret Kohler, Igor V. GrigorievAbstract:The mycorrhizal symbiosis between soil fungi and plant roots is a ubiquitous mutualism that plays key roles in plant nutrition, soil health, and carbon cycling. The symbiosis evolved repeatedly and independently as multiple morphotypes [e.g., arbuscular mycorrhizae (AM), ectomycorrhizal (ECM)] in multiple fungal clades (e.g., phyla Glomeromycota, Ascomycota, Basidiomycota). The accessibility and cultivability of many mycorrhizal partners make them ideal models for symbiosis studies. Alongside molecular, physiological, and ecological investigations, sequencing led to the first three mycorrhizal fungal genomes, representing two morphotypes and three phyla. The genome of the ECM basidiomycete Laccaria bicolor showed that the mycorrhizal lifestyle can evolve through loss of plant cell wall-degrading enzymes (PCWDEs) and expansion of lineage-specific gene families such as short secreted protein (SSP) effectors. The genome of the ECM ascomycete Tuber melanosporum showed that the ECM type can evolve without expansion of families as in Laccaria, and thus a different set of symbiosis genes. The genome of the AM glomeromycete Rhizophagus irregularis showed that despite enormous phylogenetic distance and morphological difference from the other two fungi, symbiosis can involve similar solutions as symbiosis-induced SSPs and loss of PCWDEs. The three genomes provide a solid base for addressing fundamental questions about the nature and role of a vital mutualism.
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expansion of signal pathways in the ectomycorrhizal fungus Laccaria bicolor evolution of nucleotide sequences and expression patterns in families of protein kinases and ras small gtpases
New Phytologist, 2009Co-Authors: Balaji Rajashekar, Francis Martin, Annegret Kohler, Tomas Johansson, Anders Tunlid, Dag AhrénAbstract:* The ectomycorrhizal fungus Laccaria bicolor has the largest genome of all fungi yet sequenced. The large genome size is partly a result of an expansion of gene family sizes. Among the largest gene families are protein kinases and RAS small guanosine triphosphatases (GTPases), which are key components of signal transduction pathways. * Comparative genomics and phylogenetic analyses were used to examine the evolution of the two largest families of protein kinases and RAS small GTPases in L. bicolor. Expression levels in various tissues and growth conditions were inferred from microarray data. * The two families possessed a large number of young duplicates (paralogs) that had arisen in the Laccaria lineage following the separation from the saprophyte Coprinopsis cinerea. The protein kinase paralogs were dispersed in many small clades and the majority were pseudogenes. By contrast, the RAS paralogs were found in three large groups of RAS1-, RAS2- and RHO1-like GTPases with few pseudogenes. * Duplicates of protein kinases and RAS small GTPase have either retained, gained or lost motifs found in the coding regions of their ancestors. Frequent outcomes during evolution were the formation of pseudogenes (nonfunctionalization) or proteins with novel structures and expression patterns (neofunctionalization). (Less)
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Expansion of signal pathways in the ectomycorrhizal fungus Laccaria bicolor – evolution of nucleotide sequences and expression patterns in families of protein kinases and RAS small GTPases
New Phytologist, 2009Co-Authors: Balaji Rajashekar, Francis Martin, Annegret Kohler, Tomas Johansson, Anders Tunlid, Dag AhrénAbstract:The ectomycorrhizal fungus Laccaria bicolor has the largest genome of all fungi yet sequenced. The large genome size is partly a result of an expansion of gene family sizes. Among the largest gene families are protein kinases and RAS small guanosine triphosphatases (GTPases), which are key components of signal transduction pathways. Comparative genomics and phylogenetic analyses were used to examine the evolution of the two largest families of protein kinases and RAS small GTPases in L. bicolor. Expression levels in various tissues and growth conditions were inferred from microarray data. The two families possessed a large number of young duplicates (paralogs) that had arisen in the Laccaria lineage following the separation from the saprophyte Coprinopsis cinerea. The protein kinase paralogs were dispersed in many small clades and the majority were pseudogenes. By contrast, the RAS paralogs were found in three large groups of RAS1-, RAS2- and RHO1-like GTPases with few pseudogenes. Duplicates of protein kinases and RAS small GTPase have either retained, gained or lost motifs found in the coding regions of their ancestors. Frequent outcomes during evolution were the formation of pseudogenes (nonfunctionalization) or proteins with novel structures and expression patterns (neofunctionalization).
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Développement de la symbiose ectomycorhizienne
Biofutur, 2009Co-Authors: Judith Richter, Francis Martin, Valérie LeguéAbstract:La majorité des racines des arbres de nos forêts est colonisée par des champignons, conduisant à la formation d’une symbiose appelée ectomycorhize. Cette interaction est accompagnée d’un fort développement racinaire de la plante hôte. Des expériences physiologiques et moléculaires suggèrent le rôle important des phytohormones telles que l’auxine et l’éthylène dans la modification de la formation des racines du peuplier induit par le champignon ectomycorhizien, Laccaria bicolor.
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T-DNA insertion, plasmid rescue and integration analysis in the model mycorrhizal fungus Laccaria bicolor
Microbial Biotechnology, 2008Co-Authors: Minna Kemppainen, Sébastien Duplessis, Francis Martin, Alejandro G. PardoAbstract:Ectomycorrhiza is a mutualistic symbiosis formed between fine roots of trees and the mycelium of soil fungi. This symbiosis plays a key role in forest ecosystems for the mineral nutrition of trees and the biology of the fungal communities associated. The characterization of genes involved in developmental and metabolic processes is important to understand the complex interactions that control the ectomycorrhizal symbiosis. Agrobacterium-mediated gene transfer (AMT) in fungi is currently opening a new era for fungal research. As whole genome sequences of several fungi are being released studies about T-DNA integration patterns are needed in order to understand the integration mechanisms involved and to evaluate the AMT as an insertional mutagenesis tool for different fungal species. The first genome sequence of a mycorrhizal fungus, the basidiomycete Laccaria bicolor, became public in July 2006. Release of Laccaria genome sequence and the availability of AMT makes this fungus an excellent model for functional genomic studies in ectomycorrhizal research. No data on the integration pattern in Laccaria genome were available, thus we optimized a plasmid rescue approach for this fungus. To this end the transformation vector (pHg/pBSk) was constructed allowing the rescue of the T-DNA right border (RB)–genomic DNA junctions in Escherichia coli. Fifty-one Agrobacterium-transformed fungal strains, picked up at random from a larger collection of T-DNA tagged strains (about 500), were analysed. Sixty-nine per cent were successfully rescued for the RB of which 87% were resolved for genomic integration sequences. Our results demonstrate that the plasmid rescue approach can be used for resolving T-DNA integration sites in Laccaria. The RB was well conserved during transformation of this fungus and the integration analysis showed no clear sequence homology between different genomic sites. Neither obvious sequence similarities were found between these sites and the T-DNA borders indicating non-homologous integration of the transgenes. Majority (75%) of the integrations were located in predicted genes. Agrobacterium-mediated gene transfer is a powerful tool that can be used for functional gene studies in Laccaria and will be helpful along with plasmid rescue in searching for relevant fungal genes involved in the symbiotic process.
Gregory M Mueller - One of the best experts on this subject based on the ideXlab platform.
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Novel Laccaria Species From Juglandaceae Forest in Panama With Notes on Their Ecology.
Frontiers in Microbiology, 2020Co-Authors: Adriana Corrales, Andrew W Wilson, Gregory M Mueller, Clark L. OvreboAbstract:Since 2013 there have been 22 new species of Laccaria described worldwide. Only three of these represent species from the neotropics. In Panama, Laccaria is abundant in monodominant Oreomunnea mexicana (Juglandaceae) forests based on sporocarps and environmental sequencing of roots. This study uses a combination of morphological and phylogenetic evidence to document up to seven species of Laccaria from these forests, one previously described, three described as new, and three requiring more data before being formally described. Molecular data used for phylogenetic analysis include the nuclear ribosomal ITS and 28S regions, along with TEF1 and RPB2. Laccaria stellata, has previously been reported from O. mexicana cloud forests of Panama. Laccaria dallingii sp. nov., L. nitrophila sp. nov., and L. fortunensis sp. nov. are described as new based on morphology and phylogenetic analysis of multiple collections. A taxon referred to as "PAN sp3" is resolved sister to L. stellata. Phylogenetic analysis also resolved two separate clades of Panamanian Laccaria as sister to L. roseoalbescens, a species previously described from Mexico. These three taxa are not described in this paper as there is too little material from which to make effective morphological descriptions even though their placement in phylogenetic analysis identify them as being unique. Ecologically, all described species except for L. fortunensis were amplified from O. mexicana ectomycorrhizal root tips. L. nitrophila was one of the most recovered species from the roots of O. mexicana in a previous study, and it has been shown to respond positively to long term nitrogen addition. Our results expand the knowledge of Laccaria diversity for Central America and highlight that at least some species of Laccaria are nitrophilic in neotropical Juglandaceae forests as well as in temperate forests.
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A systematic revision of the ectomycorrhizal genus Laccaria from Korea.
Mycologia, 2018Co-Authors: Hae Jin Cho, Andrew W Wilson, Gregory M Mueller, Myung Soo Park, Hyun Soon Lee, Young Woon LimAbstract:Species of Laccaria (Hydnangiaceae, Basidiomycota) are important in forest ecosystems as ectomycorrhizal fungi. Nine of the 75 described Laccaria species worldwide been reported from Korea. Most of these have European and North American names, and their identities are based solely on morphological features. To evaluate the taxonomy of Korean Laccaria, we used 443 specimens collected between 1981 and 2016 in a phylogenetic analysis based on sequence data from nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 rDNA (ITS) region, nuc 28S rDNA (28S), RNA polymerase II subunit 2 (rpb2), and translation elongation factor 1-α (tef1). Ten Laccaria species were identified. Three of these were previously reported from Korea: L. bicolor, L. tortilis, and L. vinaceoavellanea. Laccaria alba, L. japonica, and L. murina are confirmed as new reports from Korea. Lastly, four new Laccaria species are described: L. araneosa, L. parva, L. torosa, and L. versiforma. This study supports the general contention that Asian species of ectomycorrhizal fungi may not be conspecific with morphologically similar species from Europe and North America. Furthermore, identification based on morphology alone is often unreliable in Laccaria due to considerable overlap of characters among species. Thus, use of molecular methods is necessary for effective identification. Illustrations of the four newly described species and a taxonomic key to species of Laccaria in Korea are provided.
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Biogeography of the Ectomycorrhizal Mushroom Genus Laccaria
Biogeography of Mycorrhizal Symbiosis, 2017Co-Authors: Andrew W Wilson, Tom W. May, Gregory M MuellerAbstract:The mushroom genus Laccaria is one of the very few ectomycorrhizal lineages whose diversity has been explored from the phylogenetic, population genetic, genomic, and ecological perspectives. The genus serves as a model for understanding the biology of ectomycorrhizal fungi. This chapter provides an in-depth overview of the systematic diversity, ecology, host associations, and phylogenetic relationships that helped shape the current distribution of Laccaria species. This chapter discusses the challenges in identifying and delimiting species of Laccaria, along with the potential influence of life-history strategy and ecological role on the speciation and dispersal of Laccaria. The biogeographic histories of several well-documented and important ectomycorrhizal hosts of Laccaria are reviewed. These histories provide a backdrop to examine potential migration and dispersal routes during the diversification of Laccaria. They reveal historical distribution patterns that explain how ectomycorrhizal symbioses likely shaped the biogeography of Laccaria. The phylogenetic history and global systematic diversity of Laccaria is reviewed in the final sections, which include discussions of the Southern Hemisphere origins of the genus, a hypothesis for dispersal to the Northern Hemisphere, and the challenges of correlating diversity and distribution patterns in the Northern Hemisphere. Altogether, Laccaria represents a genus that is rich with opportunities to explore the ecological and evolutionary forces shaping the biogeography of ectomycorrhizal fungi.
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Evolution of ectomycorrhizas as a driver of diversification and biogeographic patterns in the model mycorrhizal mushroom genus Laccaria.
New Phytologist, 2016Co-Authors: Andrew W Wilson, Kentaro Hosaka, Gregory M MuellerAbstract:Summary A systematic and evolutionary ecology study of the model ectomycorrhizal (ECM) genus Laccaria was performed using herbarium material and field collections from over 30 countries covering its known geographic range. A four-gene (nrITS, 28S, RPB2, EF1α) nucleotide sequence dataset consisting of 232 Laccaria specimens was analyzed phylogenetically. The resulting Global Laccaria dataset was used for molecular dating and estimating diversification rates in the genus. Stable isotope analysis of carbon and nitrogen was used to evaluate the origin of Laccaria's ECM ecology. In all, 116 Laccaria molecular species were identified, resulting in a near 50% increase in its known diversity, including the new species described herein: Laccaria ambigua. Molecular dating indicates that the most recent common ancestor to Laccaria existed in the early Paleocene (56–66 million yr ago), probably in Australasia. At this time, Laccaria split into two lineages: one represented by the new species L. ambigua, and the other reflecting a large shift in diversification that resulted in the remainder of Laccaria. L. ambigua shows a different isotopic profile than all other Laccaria species. Isotopes and diversification results suggest that the evolution of the ECM ecology was a key innovation in the evolution of Laccaria. Diversification shifts associated with Laccaria's dispersal to the northern hemisphere are attributed to adaptations to new ecological niches.
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Laccaria agaricomycetes basidiomycota from tibet xizang autonomous region china
Mycoscience, 2013Co-Authors: Andrew W Wilson, Brian A Perry, Kentaro Hosaka, Gregory M MuellerAbstract:Abstract Species of Laccaria are described from the eastern Himalayas, in the Xizang Autonomous Region of China, more commonly known as Tibet. Specimens were collected during several expeditions over a 12-year time span. Nuclear ribosomal internally transcribed spacer regions 1 and 2 including and 5.8S (ITS) as well as the 5' end of the large subunit (28S) sequence data were generated for 22 specimens from Tibet and analyzed in a dataset of 115 Laccaria samples. The results documented seven species from this region, five of which represent currently undescribed species. The taxonomy of Tibetan Laccaria is discussed, five new species are proposed, and an artificial key that includes extralimital species from Asia is provided.
