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James D Bever - One of the best experts on this subject based on the ideXlab platform.
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taxonomic revision transferring species in kuklospora to Acaulospora glomeromycota and a description of Acaulospora colliculosa sp nov from field collected spores
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis are erected as new combinations (formerly Kuklospora colombiana and Kuklospora kentinensis). Mode of spore formation is demoted from a genus-specific character to one that is included with other traits to define Acaulospora species. In addition we describe a new AM fungal species, Acaulospora colliculosa (Acaulosporaceae), that originated from a tallgrass prairie in North America. Field-collected spores of A. colliculosa are small (<100 μm diam), hyaline or subhyaline to pale yellow and form via entrophosporoid development based on structure and organization of cicatrices and attached hyphae. Each spore consists of a bilayered spore wall and two bilayered inner walls. A germination orb likely forms after the completion of spore development to initiate germination, but this structure was not observed. A character distinguishing A. colliculosa from other Acaulospora species is hyaline to subhyaline hemispherical protuberances on the surface of the outer spore wall layer. A phylogeny reconstructed from partial nrLSU gene sequences unambiguously placed A. colliculosa in the Acaulospora clade.
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Taxonomic revision transferring species in Kuklospora to Acaulospora (Glomeromycota) and a description of Acaulospora colliculosa sp. nov. from field collected spores
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis a...
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Taxonomic revision transferring species in Kuklospora to Acaulospora (Glomeromycota) and a description of Acaulospora colliculosa sp. nov. from field collected spores.
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis are erected as new combinations (formerly Kuklospora colombiana and Kuklospora kentinensis). Mode of spore formation is demoted from a genus-specific character to one that is included with other traits to define Acaulospora species. In addition we describe a new AM fungal species, Acaulospora colliculosa (Acaulosporaceae), that originated from a tallgrass prairie in North America. Field-collected spores of A. colliculosa are small (
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Acaulospora colossica sp. nov. from an old field in North Carolina and morphological comparisons with similar species, A. laevis and A. koskei
Mycologia, 1999Co-Authors: Peggy A. Schultz, James D Bever, Joseph B MortonAbstract:A new arbuscular mycorrhizal fungal spe- cies, Acaulospora colossica, (Glomales, Acaulospora- ceae) is described, and its distribution and seasonality discussed. Spores of A. colossica develop from sac- cules that empty their contents in the developing spores. Spore wall structure consists of 3 layers, all originating from the subtending hyphae. The two in- ner layers are laminated. The outermost spore wall layer is typically sloughed off before the spores ma- ture. Two inner walls arise sequentially. Both inner walls are comprised of two layers. The outer layer of the innermost wall is beaded. Acaulospora colossica is described from a population in Durham, North Car- olina. Its name refers to the relatively large size of the spores. Finally, the morphology of the new spe- cies A. colossica is compared and contrasted to two closely related species A. laevis and A. koskei.
Joseph B Morton - One of the best experts on this subject based on the ideXlab platform.
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taxonomic revision transferring species in kuklospora to Acaulospora glomeromycota and a description of Acaulospora colliculosa sp nov from field collected spores
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis are erected as new combinations (formerly Kuklospora colombiana and Kuklospora kentinensis). Mode of spore formation is demoted from a genus-specific character to one that is included with other traits to define Acaulospora species. In addition we describe a new AM fungal species, Acaulospora colliculosa (Acaulosporaceae), that originated from a tallgrass prairie in North America. Field-collected spores of A. colliculosa are small (<100 μm diam), hyaline or subhyaline to pale yellow and form via entrophosporoid development based on structure and organization of cicatrices and attached hyphae. Each spore consists of a bilayered spore wall and two bilayered inner walls. A germination orb likely forms after the completion of spore development to initiate germination, but this structure was not observed. A character distinguishing A. colliculosa from other Acaulospora species is hyaline to subhyaline hemispherical protuberances on the surface of the outer spore wall layer. A phylogeny reconstructed from partial nrLSU gene sequences unambiguously placed A. colliculosa in the Acaulospora clade.
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Taxonomic revision transferring species in Kuklospora to Acaulospora (Glomeromycota) and a description of Acaulospora colliculosa sp. nov. from field collected spores
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis a...
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Taxonomic revision transferring species in Kuklospora to Acaulospora (Glomeromycota) and a description of Acaulospora colliculosa sp. nov. from field collected spores.
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis are erected as new combinations (formerly Kuklospora colombiana and Kuklospora kentinensis). Mode of spore formation is demoted from a genus-specific character to one that is included with other traits to define Acaulospora species. In addition we describe a new AM fungal species, Acaulospora colliculosa (Acaulosporaceae), that originated from a tallgrass prairie in North America. Field-collected spores of A. colliculosa are small (
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Acaulospora colossica sp. nov. from an old field in North Carolina and morphological comparisons with similar species, A. laevis and A. koskei
Mycologia, 1999Co-Authors: Peggy A. Schultz, James D Bever, Joseph B MortonAbstract:A new arbuscular mycorrhizal fungal spe- cies, Acaulospora colossica, (Glomales, Acaulospora- ceae) is described, and its distribution and seasonality discussed. Spores of A. colossica develop from sac- cules that empty their contents in the developing spores. Spore wall structure consists of 3 layers, all originating from the subtending hyphae. The two in- ner layers are laminated. The outermost spore wall layer is typically sloughed off before the spores ma- ture. Two inner walls arise sequentially. Both inner walls are comprised of two layers. The outer layer of the innermost wall is beaded. Acaulospora colossica is described from a population in Durham, North Car- olina. Its name refers to the relatively large size of the spores. Finally, the morphology of the new spe- cies A. colossica is compared and contrasted to two closely related species A. laevis and A. koskei.
Wittaya Kaonongbua - One of the best experts on this subject based on the ideXlab platform.
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taxonomic revision transferring species in kuklospora to Acaulospora glomeromycota and a description of Acaulospora colliculosa sp nov from field collected spores
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis are erected as new combinations (formerly Kuklospora colombiana and Kuklospora kentinensis). Mode of spore formation is demoted from a genus-specific character to one that is included with other traits to define Acaulospora species. In addition we describe a new AM fungal species, Acaulospora colliculosa (Acaulosporaceae), that originated from a tallgrass prairie in North America. Field-collected spores of A. colliculosa are small (<100 μm diam), hyaline or subhyaline to pale yellow and form via entrophosporoid development based on structure and organization of cicatrices and attached hyphae. Each spore consists of a bilayered spore wall and two bilayered inner walls. A germination orb likely forms after the completion of spore development to initiate germination, but this structure was not observed. A character distinguishing A. colliculosa from other Acaulospora species is hyaline to subhyaline hemispherical protuberances on the surface of the outer spore wall layer. A phylogeny reconstructed from partial nrLSU gene sequences unambiguously placed A. colliculosa in the Acaulospora clade.
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Taxonomic revision transferring species in Kuklospora to Acaulospora (Glomeromycota) and a description of Acaulospora colliculosa sp. nov. from field collected spores
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis a...
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Taxonomic revision transferring species in Kuklospora to Acaulospora (Glomeromycota) and a description of Acaulospora colliculosa sp. nov. from field collected spores.
Mycologia, 2010Co-Authors: Wittaya Kaonongbua, Joseph B Morton, James D BeverAbstract:In a phylogenetic study of arbuscular mycorrhizal fungal species in Acaulospora (Acaulosporaceae, Glomeromycota) we discovered that species classified in genus Kuklospora, a supposed sister clade of Acaulospora, did not partition as a monophyletic clade. Species in these two genera can be distinguished only by the position of the spore relative to a precursor structure, the sporiferous saccule, as either within (entrophosporoid) or laterally (acaulosporoid) on the saccule subtending hypha. Subsequent spore differentiation follows identical patterns and organization. Molecular phylogeny reconstructed from nrLSU gene sequences, together with developmental data, support the hypothesis that the entrophosporoid mode of spore formation evolved many times and thus represents a convergent trait of little phylogenetic significance. Therefore genus Kuklospora is rejected as a valid monophyletic group and it is integrated taxonomically into genus Acaulospora. Thus Acaulospora colombiana and Acaulospora kentinensis are erected as new combinations (formerly Kuklospora colombiana and Kuklospora kentinensis). Mode of spore formation is demoted from a genus-specific character to one that is included with other traits to define Acaulospora species. In addition we describe a new AM fungal species, Acaulospora colliculosa (Acaulosporaceae), that originated from a tallgrass prairie in North America. Field-collected spores of A. colliculosa are small (
José Oswaldo Siqueira - One of the best experts on this subject based on the ideXlab platform.
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FUNGOS MICORRÍZICOS ARBUSCULARES EM CAMPOS DE MURUNDUS APÓS A CONVERSÃO PARA SISTEMAS AGRÍCOLAS NO CERRADO
Revista Brasileira de Ciência do Solo, 2014Co-Authors: Paula Camylla Ramos Assis, Orivaldo José Saggin Júnior, José Oswaldo Siqueira, Helder Barbosa Paulino, Sidney Luiz Stürmer, Marco Aurelio Carbone CarneiroAbstract:The murundu fields (Campos de Murundus) are characterized by mounds occurring in some parts of the Cerrado (Brazilian tropical savanna) biome with important ecological functions for the maintenance of soil sustainability. Conversion to agricultural systems may lead to changes in physical, chemical, and biological soil properties not yet assessed, such as reduction in the biodiversity of arbuscular mycorrhizal fungi. The aim of this study was to evaluate how the conversion of mound fields into agricultural areas changes the community of arbuscular mycorrhizal fungi (AMF). Treatments consisted of three agricultural areas subjected to the same agricultural management and use in a chronosequence (seven, 11, and 14 years) and two in the mound fields, sampling at the top (TM) and between the mounds (EM)). AMF spores were extracted and counted, and AMF species were identified by morphological characteristics. The total AMF recovered was 27 species, made up of nine species of the Acaulosporaceae family, one Ambisporaceae, seven Glomeraceae, two Claroideoglomeraceae, and eight Gigasporaceae. Of this total, the species Acaulospora scrobiculata , Glomus macrocarpum , and Gigaspora sp occurred in all areas in the two years studied. The species Acaulospora melle a, Acaulospora cavernata , Acaulospora colombiana , Glomus diaphanum , Scutellospora reticulata , and Scutellospora sp only occurred in the mound fields. The conversion of mound fields into an agricultural area modified the occurrence and composition of the arbuscular mycorrhizal fungi community, and the species Acaulospora scrobiculata , Glomus macrocarpum , Gigaspora sp, and Claroideoglomus etunicatus occurred in all areas. The non-occurrence of some species in the crop areas, such as the species Acaulospora cavernata , Acaulospora columbiana , Rhizophagus diaphanus , Scutellospora reticulata , and Scutellospora sp, represents a loss of diversity of these fungi. Therefore, this study is the first report of the occurrence and community structure of AMF in the mound field vegetation type. It contributes to better understanding of AMF in the Cerrado biome and shows that the changes introduced by conversion of the area alter the occurrence and diversity of arbuscular mycorrhizal fungi.
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Fungos micorrízicos arbusculares em campos de murundus após a conversão para sistemas agrícolas no cerrado
Sociedade Brasileira de Ciência do Solo, 2014Co-Authors: Paula Camylla Ramos Assis, Orivaldo José Saggin Júnior, José Oswaldo Siqueira, Helder Barbosa Paulino, Sidney Luiz Stürmer, Marco Aurelio Carbone CarneiroAbstract:Os campos de murundus são fitofisionomias de ocorrência no bioma Cerrado com funções ecológicas importantes para a manutenção da sustentabilidade do solo; e a conversão para sistemas agrícolas pode provocar alterações nos atributos físicos, químicos e biológicos do solo ainda não avaliados, como a redução da biodiversidade de fungos micorrízicos arbusculares. O objetivo deste estudo foi avaliar como a conversão dos campos de murundus em áreas de sistema agrícola altera a comunidade de fungos micorrízicos arbusculares (FMAs). Os tratamentos constituíram-se de três áreas agrícolas submetidas ao mesmo manejo e uso agrícola em uma cronossequência (7, 11 e 14 anos) e duas na área referência [campo de murundus, em topo (TM) e entre os murundus (EM)]. Os esporos de FMAs foram extraídos, contados, e as espécies de FMAs identificadas pelas características morfológicas. O total de FMAs recuperado foi de 27 espécies, sendo nove espécies da família Acaulosporaceae, uma Ambisporaceae, sete Glomeraceae, duas Claroideoglomeraceae e oito Gigasporaceae. Desse total, as espécies Acaulospora scrobiculata, Glomus macrocarpum, e Gigaspora sp. ocorreram em todas as áreas nos dois anos estudados. As espécies Acaulospora mellea, Acaulospora cavernata, Acaulospora colombiana, Glomus diaphanum, Scutellospora reticulata e Scutellospora sp. só foram encontradas nos campos de murundus. A conversão de campos de murundus em área agrícola modificou a ocorrência e composição da comunidade de FMAs; as espécies Acaulospora scrobiculata, Glomus macrocarpum, Claroideoglomus etunicatus e Gigaspora sp ocorreram em todas as áreas e a não ocorrência de algumas espécies nas áreas de cultivo, como as espécies Acaulospora cavernata, Acaulospora colombiana, Rhizophagus diaphanus, Scutellospora reticulata e Scutellospora sp. representa perda de diversidade desses fungos. Portanto, este estudo tratou-se do primeiro relato da ocorrência e da estrutura da comunidade de FMAs em fitofisionomia de campos de murundus, contribuiu para o maior entendimento dos FMAs no bioma Cerrado e demonstrou que as alterações promovidas pela conversão da área alteraram a ocorrência e a diversidade dos fungos micorrízicos arbusculares
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Species richness and spore abundance of arbuscular mycorrhizal fungi across distinct land uses in Western Brazilian Amazon
Mycorrhiza, 2011Co-Authors: Sidney Luiz Stürmer, José Oswaldo SiqueiraAbstract:Arbuscular mycorrhizal fungi (AMF) were surveyed for species richness and abundance in sporulation in six distinct land uses in the western Amazon region of Brazil. Areas included mature pristine forest and sites converted to pasture, crops, agroforestry, young and old secondary forest. A total of 61 AMF morphotypes were recovered and 30% of them could not be identified to known species. Fungal communities were dominated by Glomus species but Acaulospora species produced the most abundant sporulation. Acaulospora gedanensis cf., Acaulospora foveata, Acaulospora spinosa, Acaulospora tuberculata , Glomus corymbiforme , Glomus sp15, Scutellospora pellucida , and Archaeospora trappei sporulated in all land use areas. Total spore numbers were highly variable among land uses. Mean species richness in crop, agroforestry, young and old secondary forest sites was twice that in pristine forest and pasture. fungal communities were dominated in all land use areas except young secondary forest by two or three species which accounted for 48% to 63% of all sporulation. Land uses influenced AMF community in (1) frequency of occurrence of sporulating AMF species, (2) mean species diversity, and (3) relative spore abundance. Conversion of pristine forest into distinct land uses does not appear to reduce AMF diversity. Cultural practices adopted in this region maintain a high diversity of arbuscular mycorrhizal fungi.
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Species richness and spore abundance of arbuscular mycorrhizal fungi across distinct land uses in Western
2011Co-Authors: Sidney Luiz Stürmer, José Oswaldo SiqueiraAbstract:Arbuscular mycorrhizal fungi (AMF) were sur- veyed for species richness and abundance in sporulation in six distinct land uses in the western Amazon region of Brazil. Areas included mature pristine forest and sites converted to pasture, crops, agroforestry, young and old secondary forest. A total of 61 AMF morphotypes were recovered and 30% of them could not be identified to known species. Fungal communities were dominated by Glomus species but Acaulospora species produced the most abundant sporulation. Acaulospora gedanensis cf., Acaulo- spora foveata, Acaulospora spinosa, Acaulospora tuber- culata, Glomus corymbiforme, Glomus sp15, Scutellospora pellucida, and Archaeospora trappei sporulated in all land use areas. Total spore numbers were highly variable among land uses. Mean species richness in crop, agroforestry, young and old secondary forest sites was twice that in pristine forest and pasture. fungal communities were dominated in all land use areas except young secondary forest by two or three species which accounted for 48% to 63% of all sporulation. Land uses influenced AMF community in (1) frequency of occurrence of sporulating AMF species, (2) mean species diversity, and (3) relative spore abundance. Conversion of pristine forest into distinct land uses does not appear to reduce AMF diversity. Cultural practices adopted in this region maintain a high diversity of arbuscular mycorrhizal fungi.
Peter Christie - One of the best experts on this subject based on the ideXlab platform.
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Occurrence and distribution of arbuscular mycorrhizal fungal species in three types of grassland community of the Tibetan Plateau
Ecological Research, 2009Co-Authors: Jingping Gai, Xiao-bu Cai, Peter Christie, J.q. Fan, Junling Zhang, Gu FengAbstract:Arbuscular mycorrhizal (AM) fungal spore communities and distribution patterns were surveyed in montane scrub grassland, alpine steppe, and alpine meadow sites at altitudes ranging from 3,500 to 5,200 m a.s.l. on the Tibetan Plateau. Thirty-two representative soil samples were collected from the root zone of the dominant and common plant species in late May 2004. Twenty-three AM fungal species representing six genera (Acaulospora, Entrophospora, Glomus, Pacispora, Paraglomus, and Scutellospora) were detected and species richness varied from 5.3 ± 0.8 to 10.5 ± 2.5 per site. Some AM fungal species were restricted to one vegetation type and Glomus mosseae, Glomus intraradices, and Scutellospora calospora were detected in all three vegetation types. Glomus species were found to be the most frequent and abundant in all three vegetation types. Acaulospora occurred mostly in the alpine steppe and alpine meadow. Scutellospora occurred mostly in montane scrub grassland. At the species level, Glomus mosseae was dominant in the montane scrub, Acaulospora laevis and Pacispora scintillans were dominant in the alpine steppe, and Acaulospora laevis, Pacispora scintillans, and Glomus claroideum dominated the alpine meadow. It was evident from the distribution pattern of AM fungi in the different vegetation types that the abundance and diversity of AM fungal species were lowest in the montane scrub grassland than the other two plant communities. Climatic conditions, especially temperatures, and intensity of land use may be the most important factors influencing the AM fungal community.
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Arbuscular mycorrhizal fungi associated with sedges on the Tibetan plateau
Mycorrhiza, 2006Co-Authors: Jingping Gai, Xiao-bu Cai, Gu Feng, Peter ChristieAbstract:The arbuscular mycorrhizal (AM) status of nine dominant sedge species and the diversity of AM fungi in Tibetan grassland were surveyed in the autumn of 2003 and 2004. Most of the sedge species and ecotypes examined were mycorrhizal, but Carex moorcroftii and Kobresia pusilla were of doubtful AM status, and Kobresia humilis was facultatively mycorrhizal. This is the first report of the mycorrhizal status of eight of the nine sedge species examined. Intraradical vesicles and aseptate hyphae were the structures most frequently observed. Appressoria, coils, and arbuscules were found in the roots of a few sedge species. A strong negative correlation was found between soil organic matter content and the extent of mycorrhizal colonization. Using trap cultures, 26 species of AM fungi belonging to six genera, Glomus, Acaulospora, Paraglomus, Archaeospora, Pacispora, and Scutellospora, were isolated from the soil samples collected. The frequency of occurrence of different taxa of AM fungi varied greatly. Glomus and Acaulospora were the dominant genera, and Acaulospora scrobiculata was the most frequent and abundant species. The species richness of AM fungi was 2.73 in the study area. Species richness and diversity index differed among the sedge species but were not correlated with soil factors such as pH, available P, or organic matter content.
