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Michael J Wingfield - One of the best experts on this subject based on the ideXlab platform.

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Mycological research, 2020
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis, a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria, a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the beta-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe. Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis, differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis, but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia, yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • cryphonectriaceae diaporthales a new family including cryphonectria chrysoporthe Endothia and allied genera
    Mycologia, 2006
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Michael J Wingfield
    Abstract:

    Recent phylogenetic studies on the members of the Diaporthales have shown that the order includes a number of distinct phylogenetic groups. These groups represent the Gnomoniaceae, Melanconidaceae, Valsaceae, Diaporthaceae and Togniniaceae. New groups representing undescribed families also have emerged and they have been referred to as the Schizoparme, Cryphonectria-Endothia and Harknessia complexes. In this study we define the new family Cryphonectriaceae (Diaporthales) to accommodate genera in the Cryphonectria-Endothia complex. These genera can be distinguished from those in other families or undescribed groups of the Diaporthales by the formation of orange stromatic tissue at some stage of their life cycle and a purple reaction in KOH and a yellow reaction in lactic acid associated with pigments in the stromatic tissue or in culture.

  • Amphilogia gen. nov. for Cryphonectria-like fungi from Elaeocarpus spp. in New Zealand and Sri Lanka
    Taxon, 2005
    Co-Authors: Marieka Gryzenhout, Brenda D Wingfield, Hugh F. Glen, Michael J Wingfield
    Abstract:

    The ascomycete genera Cryphonectria and Endothia are closely related members of Diaporthales. Recent DNA sequence comparisons have shown that isolates from Elaeocarpus spp. in New Zealand, previously identified as Cryphonectria radicalis and Cryphonectria gyrosa, represent a phylogenetic group distinct from those including other species of Cryphonectria and Endothia. Cryphonectria gyrosa applies to a species that occurs on Elaeocarpus glandulifer in Sri Lanka, the same host genus but a different species from which the New Zealand collections were made. The aim of this study was to provide a name for the fungi residing in the phylogenetic group from New Zealand. Morphological characters that define these fungi include superficial conical conidiomata, conidia of variable size, and ascospores with one to three septa. These characteristics are not found in other species of Cryphonectria. We also recognise a second species in the group from New Zealand that has distinctly larger ascospores. Herbarium specimens of C. gyrosa exhibit the same primary characteristics as the specimens from New Zealand and C. gyrosa is regarded as conspecific with one of the species in the New Zealand collections. A new genus, Amphilogia, is described for the collections of C. gyrosa from Sri Lanka and New Zealand, which also contains the second species from New Zealand, Amphilogia major sp. nov. Amphilogia gyrosa, Amphilogia major, Cryphonectria, Diaporthales, Elaeocarpus, Endothia,

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Fungal Biology, 2005
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the β-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe . Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • phylogenetic relationships of cryphonectria and Endothia species based on dna sequence data and morphology
    Mycologia, 2004
    Co-Authors: Henrietta Myburg, Marieka Gryzenhout, Brenda D Wingfield, Jay R Stipes, Michael J Wingfield
    Abstract:

    The fungal genera Endothia and Crypho- nectria include some of the most important patho- gens of forest trees. Despite available new technology, no comprehensive comparative study based on DNA sequence data and morphology has been done on the available isolates representing these two genera. The main objectives of this study were to assess the phylogenetic relationships among species of Crypho- nectria and Endothia, for which cultures are available, and to establish a taxonomic framework based on DNA sequence and morphological data, which will aid future studies and identification of species in these and related genera. Comparisons were based on sequence variation found in the ITS region of the ribosomal RNA operon and two regions of the b-tu- bulin gene. In addition, the morphology of these spe- cies was examined. The phylogenetic data indicated that Endothia and Cryphonectria reside in two distinct phylogenetic clades. Cryphonectria parasitica, C. ma- crospora, C. nitschkei, C. eucalypti and C. radicalis rep- resented the Cryphonectria clade. Endothia gyrosa and

Brenda D Wingfield - One of the best experts on this subject based on the ideXlab platform.

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Mycological research, 2020
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis, a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria, a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the beta-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe. Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis, differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis, but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia, yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • cryphonectriaceae diaporthales a new family including cryphonectria chrysoporthe Endothia and allied genera
    Mycologia, 2006
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Michael J Wingfield
    Abstract:

    Recent phylogenetic studies on the members of the Diaporthales have shown that the order includes a number of distinct phylogenetic groups. These groups represent the Gnomoniaceae, Melanconidaceae, Valsaceae, Diaporthaceae and Togniniaceae. New groups representing undescribed families also have emerged and they have been referred to as the Schizoparme, Cryphonectria-Endothia and Harknessia complexes. In this study we define the new family Cryphonectriaceae (Diaporthales) to accommodate genera in the Cryphonectria-Endothia complex. These genera can be distinguished from those in other families or undescribed groups of the Diaporthales by the formation of orange stromatic tissue at some stage of their life cycle and a purple reaction in KOH and a yellow reaction in lactic acid associated with pigments in the stromatic tissue or in culture.

  • Amphilogia gen. nov. for Cryphonectria-like fungi from Elaeocarpus spp. in New Zealand and Sri Lanka
    Taxon, 2005
    Co-Authors: Marieka Gryzenhout, Brenda D Wingfield, Hugh F. Glen, Michael J Wingfield
    Abstract:

    The ascomycete genera Cryphonectria and Endothia are closely related members of Diaporthales. Recent DNA sequence comparisons have shown that isolates from Elaeocarpus spp. in New Zealand, previously identified as Cryphonectria radicalis and Cryphonectria gyrosa, represent a phylogenetic group distinct from those including other species of Cryphonectria and Endothia. Cryphonectria gyrosa applies to a species that occurs on Elaeocarpus glandulifer in Sri Lanka, the same host genus but a different species from which the New Zealand collections were made. The aim of this study was to provide a name for the fungi residing in the phylogenetic group from New Zealand. Morphological characters that define these fungi include superficial conical conidiomata, conidia of variable size, and ascospores with one to three septa. These characteristics are not found in other species of Cryphonectria. We also recognise a second species in the group from New Zealand that has distinctly larger ascospores. Herbarium specimens of C. gyrosa exhibit the same primary characteristics as the specimens from New Zealand and C. gyrosa is regarded as conspecific with one of the species in the New Zealand collections. A new genus, Amphilogia, is described for the collections of C. gyrosa from Sri Lanka and New Zealand, which also contains the second species from New Zealand, Amphilogia major sp. nov. Amphilogia gyrosa, Amphilogia major, Cryphonectria, Diaporthales, Elaeocarpus, Endothia,

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Fungal Biology, 2005
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the β-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe . Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • phylogenetic relationships of cryphonectria and Endothia species based on dna sequence data and morphology
    Mycologia, 2004
    Co-Authors: Henrietta Myburg, Marieka Gryzenhout, Brenda D Wingfield, Jay R Stipes, Michael J Wingfield
    Abstract:

    The fungal genera Endothia and Crypho- nectria include some of the most important patho- gens of forest trees. Despite available new technology, no comprehensive comparative study based on DNA sequence data and morphology has been done on the available isolates representing these two genera. The main objectives of this study were to assess the phylogenetic relationships among species of Crypho- nectria and Endothia, for which cultures are available, and to establish a taxonomic framework based on DNA sequence and morphological data, which will aid future studies and identification of species in these and related genera. Comparisons were based on sequence variation found in the ITS region of the ribosomal RNA operon and two regions of the b-tu- bulin gene. In addition, the morphology of these spe- cies was examined. The phylogenetic data indicated that Endothia and Cryphonectria reside in two distinct phylogenetic clades. Cryphonectria parasitica, C. ma- crospora, C. nitschkei, C. eucalypti and C. radicalis rep- resented the Cryphonectria clade. Endothia gyrosa and

Marieka Gryzenhout - One of the best experts on this subject based on the ideXlab platform.

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Mycological research, 2020
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis, a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria, a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the beta-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe. Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis, differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis, but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia, yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • cryphonectriaceae diaporthales a new family including cryphonectria chrysoporthe Endothia and allied genera
    Mycologia, 2006
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Michael J Wingfield
    Abstract:

    Recent phylogenetic studies on the members of the Diaporthales have shown that the order includes a number of distinct phylogenetic groups. These groups represent the Gnomoniaceae, Melanconidaceae, Valsaceae, Diaporthaceae and Togniniaceae. New groups representing undescribed families also have emerged and they have been referred to as the Schizoparme, Cryphonectria-Endothia and Harknessia complexes. In this study we define the new family Cryphonectriaceae (Diaporthales) to accommodate genera in the Cryphonectria-Endothia complex. These genera can be distinguished from those in other families or undescribed groups of the Diaporthales by the formation of orange stromatic tissue at some stage of their life cycle and a purple reaction in KOH and a yellow reaction in lactic acid associated with pigments in the stromatic tissue or in culture.

  • Amphilogia gen. nov. for Cryphonectria-like fungi from Elaeocarpus spp. in New Zealand and Sri Lanka
    Taxon, 2005
    Co-Authors: Marieka Gryzenhout, Brenda D Wingfield, Hugh F. Glen, Michael J Wingfield
    Abstract:

    The ascomycete genera Cryphonectria and Endothia are closely related members of Diaporthales. Recent DNA sequence comparisons have shown that isolates from Elaeocarpus spp. in New Zealand, previously identified as Cryphonectria radicalis and Cryphonectria gyrosa, represent a phylogenetic group distinct from those including other species of Cryphonectria and Endothia. Cryphonectria gyrosa applies to a species that occurs on Elaeocarpus glandulifer in Sri Lanka, the same host genus but a different species from which the New Zealand collections were made. The aim of this study was to provide a name for the fungi residing in the phylogenetic group from New Zealand. Morphological characters that define these fungi include superficial conical conidiomata, conidia of variable size, and ascospores with one to three septa. These characteristics are not found in other species of Cryphonectria. We also recognise a second species in the group from New Zealand that has distinctly larger ascospores. Herbarium specimens of C. gyrosa exhibit the same primary characteristics as the specimens from New Zealand and C. gyrosa is regarded as conspecific with one of the species in the New Zealand collections. A new genus, Amphilogia, is described for the collections of C. gyrosa from Sri Lanka and New Zealand, which also contains the second species from New Zealand, Amphilogia major sp. nov. Amphilogia gyrosa, Amphilogia major, Cryphonectria, Diaporthales, Elaeocarpus, Endothia,

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Fungal Biology, 2005
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the β-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe . Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • phylogenetic relationships of cryphonectria and Endothia species based on dna sequence data and morphology
    Mycologia, 2004
    Co-Authors: Henrietta Myburg, Marieka Gryzenhout, Brenda D Wingfield, Jay R Stipes, Michael J Wingfield
    Abstract:

    The fungal genera Endothia and Crypho- nectria include some of the most important patho- gens of forest trees. Despite available new technology, no comprehensive comparative study based on DNA sequence data and morphology has been done on the available isolates representing these two genera. The main objectives of this study were to assess the phylogenetic relationships among species of Crypho- nectria and Endothia, for which cultures are available, and to establish a taxonomic framework based on DNA sequence and morphological data, which will aid future studies and identification of species in these and related genera. Comparisons were based on sequence variation found in the ITS region of the ribosomal RNA operon and two regions of the b-tu- bulin gene. In addition, the morphology of these spe- cies was examined. The phylogenetic data indicated that Endothia and Cryphonectria reside in two distinct phylogenetic clades. Cryphonectria parasitica, C. ma- crospora, C. nitschkei, C. eucalypti and C. radicalis rep- resented the Cryphonectria clade. Endothia gyrosa and

Henrietta Myburg - One of the best experts on this subject based on the ideXlab platform.

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Mycological research, 2020
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis, a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria, a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the beta-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe. Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis, differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis, but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia, yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • cryphonectriaceae diaporthales a new family including cryphonectria chrysoporthe Endothia and allied genera
    Mycologia, 2006
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Michael J Wingfield
    Abstract:

    Recent phylogenetic studies on the members of the Diaporthales have shown that the order includes a number of distinct phylogenetic groups. These groups represent the Gnomoniaceae, Melanconidaceae, Valsaceae, Diaporthaceae and Togniniaceae. New groups representing undescribed families also have emerged and they have been referred to as the Schizoparme, Cryphonectria-Endothia and Harknessia complexes. In this study we define the new family Cryphonectriaceae (Diaporthales) to accommodate genera in the Cryphonectria-Endothia complex. These genera can be distinguished from those in other families or undescribed groups of the Diaporthales by the formation of orange stromatic tissue at some stage of their life cycle and a purple reaction in KOH and a yellow reaction in lactic acid associated with pigments in the stromatic tissue or in culture.

  • Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.
    Fungal Biology, 2005
    Co-Authors: Marieka Gryzenhout, Henrietta Myburg, Brenda D Wingfield, Fernando Montenegro, Michael J Wingfield
    Abstract:

    Terminalia ivorensis a tree of central African origin, is planted in several tropical countries for timber and veneer production. During the course of a recent disease survey, an unknown fungus was found associated with basal cankers on dying T. ivorensis in Ecuador. The fungus has orange fruiting structures and septate, fusoid ascospores, similar to those of Cryphonectria a well-known genus of canker pathogens. The aim of this study was to identify the fungus and to assess its pathogenicity. Identification was based on morphological characteristics as well as DNA sequence data. DNA sequence data from the ITS regions of the rDNA operon and two regions of the β-tubulin gene, were compared with published sequences of Cryphonectria species and the closely related genera Endothia and Chrysoporthe . Pathogenicity tests were conducted on T. superba saplings. Morphological characterisations revealed that the conidiomata of the fungus from T. ivorensis differed from those typical of Cryphonectria in being superficial and rostrate. Only Cryphonectria longirostris was similar to the fungus from T. ivorensis but could be distinguished from it based on conidial size. Phylogenetic analyses showed that the fungus from T. ivorensis grouped closely with species of Cryphonectria, Chrysoporthe and Endothia yet formed a distinct clade. Pathogenicity tests on T. superba provided evidence that the fungus is able to cause distinct stem cankers. We conclude that the pathogenic fungus from T. ivorensis represents a new genus and new species in the Diaporthales and we provide the name Rostraureum tropicale for it. The genus is typified by R. tropicale. Furthermore, C. longirostris is transferred to Rostraureum.

  • phylogenetic relationships of cryphonectria and Endothia species based on dna sequence data and morphology
    Mycologia, 2004
    Co-Authors: Henrietta Myburg, Marieka Gryzenhout, Brenda D Wingfield, Jay R Stipes, Michael J Wingfield
    Abstract:

    The fungal genera Endothia and Crypho- nectria include some of the most important patho- gens of forest trees. Despite available new technology, no comprehensive comparative study based on DNA sequence data and morphology has been done on the available isolates representing these two genera. The main objectives of this study were to assess the phylogenetic relationships among species of Crypho- nectria and Endothia, for which cultures are available, and to establish a taxonomic framework based on DNA sequence and morphological data, which will aid future studies and identification of species in these and related genera. Comparisons were based on sequence variation found in the ITS region of the ribosomal RNA operon and two regions of the b-tu- bulin gene. In addition, the morphology of these spe- cies was examined. The phylogenetic data indicated that Endothia and Cryphonectria reside in two distinct phylogenetic clades. Cryphonectria parasitica, C. ma- crospora, C. nitschkei, C. eucalypti and C. radicalis rep- resented the Cryphonectria clade. Endothia gyrosa and

  • Phylogeny of Cryphonectria cubensis and allied species inferred from DNA analysis
    Mycologia, 1999
    Co-Authors: Henrietta Myburg, Brenda D Wingfield, Michael J Wingfield
    Abstract:

    Cryphonectria cubensis causes a serious canker disease of Eucalyptus in many tropical areas of the world. The aim of this study was to determine the phylogenetic relationships among strains of C. cubensis and the related species C. parasitica, Endothia eugeniae and E. gyrosa using DNA sequence data. A second objective was to develop a rapid diagnostic method to distinguish among these taxa. The variable ITS1 and ITS2 regions, as well as the conserved 5.8S gene of the rRNA operon, were amplified and sequenced. The amplified PCR products were also used in Alu I and Cfo I restriction digests. Analysis of the restriction profiles indicate that it is possible to distinguish between C. cubensis, C. parasitica, E. eugeniae and E. gyrosa using RFLPs (restriction fragment length polymorphisms). This will facilitate the identification of isolates thought to represent C. cubensis that sporulate poorly in culture. Analysis of the sequence data showed that C. cubensis isolates form a distinct clade that includes a strain from clove that might otherwise have been assigned the name E. eugeniae. Isolates of C. parasitica formed a separate clade. Endothia gyrosa grouped separately from both C. cubensis and C. parasitica.

C L Mohammed - One of the best experts on this subject based on the ideXlab platform.

  • pathogenicity of fungi associated with stem cankers of eucalypts in tasmania australia
    Plant Disease, 1999
    Co-Authors: Zi-qing Yuan, C L Mohammed
    Abstract:

    ABSTRACT Thirteen stem-infecting fungal species, 11 from Tasmania and 2 from other parts of southeast Australia, were tested for their pathogenicity on 12-month-old seedlings of Eucalyptus nitens and E. globulus. They were classified into three groups based on their ability to cause stem canker lesions following artificial inoculation: pathogenic species (Phoma sp., Endothia gyrosa, and Seiridium eucalypti), intermediate or weakly pathogenic species (Botryosphaeria sp., Seiridium papillatum, Pestalotiopsis neglecta, Zythiostroma sp., Ceuthospora innumera, Cytospora eucalypticola, and Wuestneia epispora), and nonpathogenic species (Dinemasporium strigosum, Seiridium unicorne, and Harknessia aff. eucalypti). The potential threat of canker fungi, especially Endothia gyrosa, to plantation forestry in Australia is discussed.