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

  • A new species of Raffaelea from beetle-infested Leucaena leucocephala.
    Fungal systematics and evolution, 2020
    Co-Authors: M. Procter, Seonju Marincowitz, W.j. Nel, P.w. Crous, Michael J. Wingfield
    Abstract:

    Species of Raffaelea (Ophiostomatales: Ascomycota) are obligate symbionts of ambrosia beetles, some of which pose a substantial threat to forest trees. Leucaena leucocephala is a small mimosoid tree species that is considered as an invasive weed in most of its introduced range globally. During a field expedition on the French island of Reunion, dying L. leucocephala trees were observed. Samples were taken from these trees and isolations made from symptomatic wood tissues that included beetle tunnels, but in the absence of the beetles themselves. Multiple isolates of a fungus resembling a Raffaelea species were obtained from the discoloured wood associated with the beetle tunnels. To determine their identity, microscopic examination was performed and DNA sequences for three gene regions (ITS, LSU, TUB) were obtained. Phylogenetic analyses based on these gene regions revealed that the isolates represent a new species of Raffaelea, described here as R. borbonicasp. nov. A pathogenicity test was conducted with the fungus, which was shown to cause lesions on the inoculated seedlings, but with a low level of aggressiveness.

  • Seven new species of Graphilbum from conifers in Norway, Poland, and Russia.
    Mycologia, 2020
    Co-Authors: Robert Jankowiak, Halvor Solheim, Piotr Bilański, Seonju Marincowitz, Michael J. Wingfield
    Abstract:

    During surveys of insect-associated mycobiomes in Norway, Poland, and Russia, isolates with affinity to Graphilbum (Ophiostomatales, Ascomycota) were recovered. In this study, eight known Graphilbum species as well as the newly collected isolates were compared based on morphology and DNA sequence data for four gene regions. The results revealed seven new species, described here as G. acuminatum, G. carpaticum, G. curvidentis, G. furuicola, G. gorcense, G. interstitiale, and G. sexdentatum. In addition to these species, G. crescericum and G. sparsum were commonly found in Norway. All new species were recovered from conifers in association with bark beetles, cerambycid beetles, and weevils and were morphologically similar, predominantly with pesotum-like asexual morphs. Where sexual morphs were present, these were small ascomata with short necks and rod-shaped ascospores having hyaline sheaths. The results suggest that Graphilbum species are common members of the Ophiostomatales in conifer ecosystems.

  • Taxonomy and phylogeny of the Leptographium olivaceum complex (Ophiostomatales, Ascomycota), including descriptions of six new species from China and Europe.
    MycoKeys, 2019
    Co-Authors: Mingliang Yin, Riikka Linnakoski, Xudong Zhou, Michael J. Wingfield, Z. Wilhelm Beer
    Abstract:

    The Leptographium olivacea complex encompasses species in the broadly defined genus Leptographium (Ophiostomatales, Ascomycota) that are generally characterized by synnematous conidiophores. Most species of the complex are associates of conifer-infesting bark beetles in Europe and North America. The aims of this study were to reconsider the delineation of known species, and to confirm the identity of several additional isolates resembling L. olivacea that have emerged from recent surveys in China, Finland, Poland, Russia, and Spain. Phylogenetic analyses of sequence data for five loci (ACT, TUB, CAL, ITS2-LSU, and TEF-1α) distinguished 14 species within the complex. These included eight known species (L. cucullatum, L. davidsonii, L. erubescens, L. francke-grosmanniae, L. olivaceum, L. olivaceapini, L. sagmatosporum, and L. vescum) and six new species (herein described as L. breviuscapum, L. conplurium, L. pseudoalbum, L. rhizoidum, L. sylvestris, and L. xiningense). New combinations are provided for L. cucullatum, L. davidsonii, L. erubescens, L. olivaceum, L. olivaceapini, L. sagmatosporum and L. vescum. New Typifications: Lectotypes are designated for L. olivaceum, L. erubescens and L. sagmatosporum. Epitypes were designated for L. olivaceapini and L. sagmatosporum. In addition to phylogenetic separation, the synnematous asexual states and ascomata with almost cylindrical necks and prominent ostiolar hyphae, distinguish the L. olivaceum complex from others in Leptographium.

  • Ophiostomatoid fungi associated with conifer-infesting beetles and their phoretic mites in Yunnan, China.
    MycoKeys, 2017
    Co-Authors: Runlei Chang, Xudong Zhou, Tuan A. Duong, Stephen J. Taerum, Michael J. Wingfield, Z. Wilhelm Beer
    Abstract:

    The Ophiostomatales is an Ascomycete order of fungi that accommodates several tree pathogens and many species that degrade wood. These fungi are commonly vectored by Scolytine bark and ambrosia beetles. In recent years it has also been shown that hyperphoretic mites on these beetles can vector some Ophiostomatales. Little is known regarding the Ophiostomatales in China and we have consequently explored the diversity of these fungi associated with conifer-infesting beetles and mites in Yunnan province. Galleries and beetles were collected for 17 beetle species, while 13 mite species were obtained from six of these beetle species. Collectively, 340 fungal isolates were obtained, 45 from beetles, 184 from mites, 56 from galleries and 55 isolates where the specific niche was not clear. DNA sequences for five gene regions (ITS, LSU, BT, EF, and CAL) were determined for fungal isolates representing different morphological groups. Phylogenetic analyses confirmed the presence of 19 fungal taxa, including five novel species described here as Ophiostoma acarorumsp. nov., Ophiostoma brevipilosisp. nov., Graphilbum kesiyaesp. nov., Graphilbum puerensesp. nov., and Leptographium ningerensesp. nov.Ophiostoma ips was the most frequently isolated species, representing approximately 31% of all isolates. Six of 19 taxa were present on mites, beetles and in the galleries of the beetles, while three species were found on mites and galleries. Two species were found only on mites and one species only on a beetle. Although the numbers of beetles and mites were insufficient to provide statistical inferences, this study confirmed that mites are important vectors of the Ophiostomatales in China. We hypothesize that these mites are most likely responsible for horizontal transfer of fungal species between galleries of different beetle species. The fact that half of the fungal species found were new to science, suggests that the forests of east Asia include many undescribed Ophiostomatales yet to be discovered.

  • Antifungal actinomycetes associated with the pine bark beetle, Orthotomicus erosus, in South Africa
    South African Journal of Science, 2017
    Co-Authors: Zander R. Human, Z. Wilhelm Beer, Michael J. Wingfield, Bernard Slippers, Stephanus N. Venter
    Abstract:

    Abstract Actinomycete bacteria are often associated with insects that have a mutualistic association with fungi. These bacteria are believed to be important to this insect–fungus association as they produce antibiotics that exclude other saprophytic fungi from the immediate environment. The aim of this study was to investigate the presence of potentially protective actinomycetes associated with Orthotomicus erosus, an alien invasive pine bark beetle, in South Africa. This bark beetle and its relatives have an association with Ophiostomatales species which are often the only fungi found in the bark beetle galleries. We hypothesised that antibiotic-producing actinomycetes could be responsible for the paucity of other fungi in the galleries by producing compounds to which the Ophiostoma spp. are tolerant. Several actinomycetes in the genus Streptomyces and one Gordonia sp. were isolated from the beetle. Interestingly, most isolates were from the same species as actinomycetes associated with other pine-infesting insects from other parts of the world, including bark beetles and the woodwasp Sirex noctilio. Most actinomycetes isolated had strong antifungal properties against the selected test fungi, including Ophiostoma ips, which is the most common fungal symbiont of Orthotomicus erosus. Although the actinomycetes did not benefit Ophiostoma ips and the hypothesis was not supported, their sporadic association with Orthotomicus erosus suggests that they could have some impact on the composition of the fungal communities present in the bark beetle galleries, which is at present poorly understood.

Riikka Linnakoski - One of the best experts on this subject based on the ideXlab platform.

  • Taxonomy and phylogeny of the Leptographium olivaceum complex (Ophiostomatales, Ascomycota), including descriptions of six new species from China and Europe.
    MycoKeys, 2019
    Co-Authors: Mingliang Yin, Riikka Linnakoski, Xudong Zhou, Michael J. Wingfield, Z. Wilhelm Beer
    Abstract:

    The Leptographium olivacea complex encompasses species in the broadly defined genus Leptographium (Ophiostomatales, Ascomycota) that are generally characterized by synnematous conidiophores. Most species of the complex are associates of conifer-infesting bark beetles in Europe and North America. The aims of this study were to reconsider the delineation of known species, and to confirm the identity of several additional isolates resembling L. olivacea that have emerged from recent surveys in China, Finland, Poland, Russia, and Spain. Phylogenetic analyses of sequence data for five loci (ACT, TUB, CAL, ITS2-LSU, and TEF-1α) distinguished 14 species within the complex. These included eight known species (L. cucullatum, L. davidsonii, L. erubescens, L. francke-grosmanniae, L. olivaceum, L. olivaceapini, L. sagmatosporum, and L. vescum) and six new species (herein described as L. breviuscapum, L. conplurium, L. pseudoalbum, L. rhizoidum, L. sylvestris, and L. xiningense). New combinations are provided for L. cucullatum, L. davidsonii, L. erubescens, L. olivaceum, L. olivaceapini, L. sagmatosporum and L. vescum. New Typifications: Lectotypes are designated for L. olivaceum, L. erubescens and L. sagmatosporum. Epitypes were designated for L. olivaceapini and L. sagmatosporum. In addition to phylogenetic separation, the synnematous asexual states and ascomata with almost cylindrical necks and prominent ostiolar hyphae, distinguish the L. olivaceum complex from others in Leptographium.

  • Four new Ophiostoma species associated with conifer- and hardwood-infesting bark and ambrosia beetles from the Czech Republic and Poland
    Antonie Van Leeuwenhoek International Journal of General and Molecular Microbiology, 2019
    Co-Authors: Robert Jankowiak, Agnieszka Bosak, Piotr Bilański, Riikka Linnakoski, Beata Strzałka, Georg Hausner
    Abstract:

    Fungi under the order Ophiostomatales (Ascomycota) are known to associate with various species of bark beetles (Coleoptera: Curculionidae: Scolytinae). In addition this group of fungi contains many taxa that can impart blue-stain on sapwood and some are important tree pathogens. A recent survey that focussed on the diversity of the Ophiostomatales in the forest ecosystems of the Czech Republic and Poland uncovered four putative new species. Phylogenetic analyses of four gene regions (ITS1-5.8S-ITS2 region, s-tubulin, calmodulin, and translation elongation factor 1-α) indicated that these four species are members of the genus Ophiostoma. All four newly described species can be distinguished from each other and from closely related species based on DNA sequence comparisons, morphological characters, growth rates, and their insect associations. Based on this study four new taxa can be circumscribed and the following names are provided: Ophiostoma pityokteinis sp. nov., Ophiostoma rufum sp. nov., Ophiostoma solheimii sp. nov., and Ophiostoma taphrorychi sp. nov. O. rufum sp. nov. is a member of the Ophiostoma piceae species complex, while O. pityokteinis sp. nov. resides in a discrete lineage within Ophiostoma s. stricto. O. taphrorychi sp. nov. together with O. distortum formed a well-supported clade in Ophiostoma s. stricto close to O. pityokteinis sp. nov. O. solheimii sp. nov. groups within a currently undefined lineage A, which also includes Ophiostoma grandicarpum and Ophiostoma microsporum. This study highlights the need for more intensive surveys that should include additional countries of Central Europe, insect vectors and host tree species in order to elucidate Ophiostoma species diversity in this region.

  • Ophiostomatoid fungi associated with hardwood-infesting bark and ambrosia beetles in Poland: Taxonomic diversity and vector specificity
    Fungal Ecology, 2019
    Co-Authors: Robert Jankowiak, Beata Strzałka, Magdalena Kacprzyk, Piotr Bilański, Piotr Wieczorek, Riikka Linnakoski
    Abstract:

    Abstract Fungi in the orders Ophiostomatales and Microascales (Ascomycota), often designated as ophiostomatoid fungi, are frequent associates of scolytine bark and ambrosia beetles that colonize hardwood and coniferous trees. Several species, e.g., Ophiostoma novo-ulmi, are economically damaging pathogens of trees. Because little is known regarding the ophiostomatoid fungi in Europe, we have explored the diversity of these fungi associated with hardwood-infesting beetles in Poland. This study aims to clarify the associations between fungi in the genera Ambrosiella, Graphium (Microascales), Graphilbum, Leptographium, Ophiostoma and Sporothrix (Ophiostomatales) and their beetle vectors in hardwood ecosystems. Samples associated with 18 bark and ambrosia beetle species were collected from 11 stands in Poland. Fungi were isolated from adult beetles and galleries. Isolates were identified based on morphology, DNA sequence comparisons for five gene regions (ITS, LSU, sT, TEF 1-α, and CAL) and phylogenetic analyses. In total, 36 distinct taxa were identified, including 24 known and 12 currently unknown species. Several associations between fungi and bark and ambrosia beetles were recorded for the first time. In addition, associations between Dryocoetes alni, D. villosus, Hylesinus crenatus, Ernoporus tiliae, Pteleobius vittatus and ophiostomatoid fungi were reported for the first time, and Sporothrix eucastanea was reported for the first time outside of the USA. Among the species of Ophiostomatales, 14 species were in Ophiostoma s. l., two species were in Graphilbum, nine species were in Sporothrix, and seven species were in Leptographium s. l. Among the species of Microascales, three species were in Graphium, and one was in Ambrosiella. Twenty taxa were present on the beetles and in the galleries, twelve only on beetles, and four only in galleries. Bark and ambrosia beetles from hardwoods appear to be regular vectors, with ophiostomatoid fungi present in all the beetle species. Most ophiostomatoid species had a distinct level of vector/host specificity, although Ophiostoma quercus, the most frequently encountered species, also had the greatest range of beetle vectors and tree hosts. Plant pathogenic O. novo-ulmi was found mainly in association with elm-infesting bark beetles (Scolytus multistriatus, S. scolytus, and P. vittatus) and occasionally with H. crenatus on Fraxinus excelsior and with Scolytus intricatus on Quercus robur.

  • Ophiostomatales associated with wounds on hardwood trees in Poland
    Plant Pathology, 2019
    Co-Authors: Robert Jankowiak, Piotr Bilański, A. Ostafińska, Riikka Linnakoski
    Abstract:

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  • Three new Leptographium spp. (Ophiostomatales) infecting hardwood trees in Norway and Poland
    Antonie van Leeuwenhoek, 2018
    Co-Authors: Robert Jankowiak, Agnieszka Ostafińska, Piotr Bilański, Riikka Linnakoski, Halvor Solheim, Georg Hausner
    Abstract:

    Species of Leptographium are characterized by mononematous or synnematous conidiophores and are commonly associated with different arthropods. Some of them also produce a sexual state characterised by globose ascomata with elongated necks. Compared to investigations on coniferous trees, the occurrence of Leptographium species on hardwood trees has been poorly studied in Europe. During a survey of ophiostomatoid fungi on various hardwood tree species in Norway and Poland, three unusual species, which fit in the broader morphological description of Leptographium spp., were found in association with Trypodendron domesticum , Trypodendron signatum and Dryocoetes alni , and from wounds on a variety of hardwoods. Phylogenetic analyses of sequence data for six different loci (ITS1–5.8 S–ITS2, ITS2-LSU, ACT, β-tubulin, CAL, and TEF-1α) showed that these Leptographium species are phylogenetically closely related to the species of the Grosmannia olivacea complex. The first species forms a well-supported lineage that includes Ophiostoma brevicolle , while the two other new taxa resided in a separate lineage; possibly affiliated with Grosmannia francke - grosmanniae . All the new species produce perithecia with necks terminating in ostiolar hyphae and orange-section shaped ascospores with cucullate, gelatinous sheaths. These species also produce dark olivaceous mononematous asexual states in culture. In addition, two of the newly described species have a second type of conidiophore with a short and non-pigmented stipe. The new Leptographium species can be easily distinguished from each other by their appearance and growth in culture. Based on novel morphological characters and distinct DNA sequences, these fungi were recognised as new taxa for which the names Leptographium tardum sp. nov., Leptographium vulnerum sp. nov., and Leptographium flavum sp. nov. are provided.

Z. Wilhelm Beer - One of the best experts on this subject based on the ideXlab platform.

  • Taxonomy and phylogeny of the Leptographium olivaceum complex (Ophiostomatales, Ascomycota), including descriptions of six new species from China and Europe.
    MycoKeys, 2019
    Co-Authors: Mingliang Yin, Riikka Linnakoski, Xudong Zhou, Michael J. Wingfield, Z. Wilhelm Beer
    Abstract:

    The Leptographium olivacea complex encompasses species in the broadly defined genus Leptographium (Ophiostomatales, Ascomycota) that are generally characterized by synnematous conidiophores. Most species of the complex are associates of conifer-infesting bark beetles in Europe and North America. The aims of this study were to reconsider the delineation of known species, and to confirm the identity of several additional isolates resembling L. olivacea that have emerged from recent surveys in China, Finland, Poland, Russia, and Spain. Phylogenetic analyses of sequence data for five loci (ACT, TUB, CAL, ITS2-LSU, and TEF-1α) distinguished 14 species within the complex. These included eight known species (L. cucullatum, L. davidsonii, L. erubescens, L. francke-grosmanniae, L. olivaceum, L. olivaceapini, L. sagmatosporum, and L. vescum) and six new species (herein described as L. breviuscapum, L. conplurium, L. pseudoalbum, L. rhizoidum, L. sylvestris, and L. xiningense). New combinations are provided for L. cucullatum, L. davidsonii, L. erubescens, L. olivaceum, L. olivaceapini, L. sagmatosporum and L. vescum. New Typifications: Lectotypes are designated for L. olivaceum, L. erubescens and L. sagmatosporum. Epitypes were designated for L. olivaceapini and L. sagmatosporum. In addition to phylogenetic separation, the synnematous asexual states and ascomata with almost cylindrical necks and prominent ostiolar hyphae, distinguish the L. olivaceum complex from others in Leptographium.

  • Ophiostomatoid fungi associated with conifer-infesting beetles and their phoretic mites in Yunnan, China.
    MycoKeys, 2017
    Co-Authors: Runlei Chang, Xudong Zhou, Tuan A. Duong, Stephen J. Taerum, Michael J. Wingfield, Z. Wilhelm Beer
    Abstract:

    The Ophiostomatales is an Ascomycete order of fungi that accommodates several tree pathogens and many species that degrade wood. These fungi are commonly vectored by Scolytine bark and ambrosia beetles. In recent years it has also been shown that hyperphoretic mites on these beetles can vector some Ophiostomatales. Little is known regarding the Ophiostomatales in China and we have consequently explored the diversity of these fungi associated with conifer-infesting beetles and mites in Yunnan province. Galleries and beetles were collected for 17 beetle species, while 13 mite species were obtained from six of these beetle species. Collectively, 340 fungal isolates were obtained, 45 from beetles, 184 from mites, 56 from galleries and 55 isolates where the specific niche was not clear. DNA sequences for five gene regions (ITS, LSU, BT, EF, and CAL) were determined for fungal isolates representing different morphological groups. Phylogenetic analyses confirmed the presence of 19 fungal taxa, including five novel species described here as Ophiostoma acarorumsp. nov., Ophiostoma brevipilosisp. nov., Graphilbum kesiyaesp. nov., Graphilbum puerensesp. nov., and Leptographium ningerensesp. nov.Ophiostoma ips was the most frequently isolated species, representing approximately 31% of all isolates. Six of 19 taxa were present on mites, beetles and in the galleries of the beetles, while three species were found on mites and galleries. Two species were found only on mites and one species only on a beetle. Although the numbers of beetles and mites were insufficient to provide statistical inferences, this study confirmed that mites are important vectors of the Ophiostomatales in China. We hypothesize that these mites are most likely responsible for horizontal transfer of fungal species between galleries of different beetle species. The fact that half of the fungal species found were new to science, suggests that the forests of east Asia include many undescribed Ophiostomatales yet to be discovered.

  • Two new Leptographium spp. reveal an emerging complex of hardwood-infecting species in the Ophiostomatales
    Antonie van Leeuwenhoek, 2017
    Co-Authors: Robert Jankowiak, Piotr Bilański, Riikka Linnakoski, Beata Strzałka, Małgorzata Groszek, Halvor Solheim, Z. Wilhelm Beer
    Abstract:

    Species of Leptographium are generally characterized by mononematous conidiophores and are commonly associated with bark beetles and weevils. These species are responsible for sapstain and in some cases serious diseases on a range of primarily coniferous trees. In comparison with coniferous trees, the occurrence of Leptographium species on hardwood trees has been poorly studied in Europe. During a survey of ophiostomatoid fungi on various tree species in Norway and Poland, three unusual species, which fit the broader morphological description of Leptographium spp., were found in association with Scolytus ratzeburgi , Dryocoetes alni and Trypodendron domesticum on a variety of hardwoods, and from wounds on Tilia cordata . Phylogenetic analyses of sequence data for three gene regions (ITS2-LSU, β-tubulin, and TEF1-α) showed that these Leptographium species are phylogenetically closely related to each other and form a well-supported lineage that included Grosmannia grandifoliae and Leptographium pruni . The first species could be distinguished from the other Leptographium species based on conidiophores arising from spiral hyphae, chlamydospore-like structures and a hyalorhinocladiella-like synanamorph in culture. The second species differs from the previous one by having distinctly shorter conidiophores and smaller conidia. This species also produces a well-developed sporothrix-like synanamorph with denticulate conidiogenous cells. Based on these unusual morphological characteristics and distinct DNA sequences, these fungi were recognised as new taxa for which the names Leptographium trypodendri sp. nov. and L. betulae sp. nov. are provided. The third group of isolates belonged to Grosmannia grandifoliae , representing the first report of this species outside of the USA. The newly defined G. grandifoliae complex is the first species complex in Leptographium s.l. consisting of only hardwood-infecting species.

  • Antifungal actinomycetes associated with the pine bark beetle, Orthotomicus erosus, in South Africa
    South African Journal of Science, 2017
    Co-Authors: Zander R. Human, Z. Wilhelm Beer, Michael J. Wingfield, Bernard Slippers, Stephanus N. Venter
    Abstract:

    Abstract Actinomycete bacteria are often associated with insects that have a mutualistic association with fungi. These bacteria are believed to be important to this insect–fungus association as they produce antibiotics that exclude other saprophytic fungi from the immediate environment. The aim of this study was to investigate the presence of potentially protective actinomycetes associated with Orthotomicus erosus, an alien invasive pine bark beetle, in South Africa. This bark beetle and its relatives have an association with Ophiostomatales species which are often the only fungi found in the bark beetle galleries. We hypothesised that antibiotic-producing actinomycetes could be responsible for the paucity of other fungi in the galleries by producing compounds to which the Ophiostoma spp. are tolerant. Several actinomycetes in the genus Streptomyces and one Gordonia sp. were isolated from the beetle. Interestingly, most isolates were from the same species as actinomycetes associated with other pine-infesting insects from other parts of the world, including bark beetles and the woodwasp Sirex noctilio. Most actinomycetes isolated had strong antifungal properties against the selected test fungi, including Ophiostoma ips, which is the most common fungal symbiont of Orthotomicus erosus. Although the actinomycetes did not benefit Ophiostoma ips and the hypothesis was not supported, their sporadic association with Orthotomicus erosus suggests that they could have some impact on the composition of the fungal communities present in the bark beetle galleries, which is at present poorly understood.

  • New Raffaelea species (Ophiostomatales) from the USA and Taiwan associated with ambrosia beetles and plant hosts.
    IMA fungus, 2016
    Co-Authors: D. Rabern Simmons, Z. Wilhelm Beer, Yin-tse Huang, Craig C. Bateman, Alina Campbell, T. J. Dreaden, Randy C. Ploetz, Adam Black
    Abstract:

    Raffaelea (Ophiostomatales) is a genus of more than 20 ophiostomatoid fungi commonly occurring in symbioses with wood-boring ambrosia beetles. We examined ambrosia beetles and plant hosts in the USA and Taiwan for the presence of these mycosymbionts and found 22 isolates representing known and undescribed lineages in Raffaelea. From 28S rDNA and β-tubulin sequences, we generated a molecular phylogeny of Ophiostomatales and observed morphological features of seven cultures representing undescribed lineages in Raffaelea s. lat. From these analyses, we describe five new species in Raffaelea s. lat.: R. aguacate, R. campbellii, R. crossotarsa, R. cyclorhipidia, and R. xyleborina spp. nov. Our analyses also identified two plantpathogenic species of Raffaelea associated with previously undocumented beetle hosts: (1) R. quercivora, the causative agent of Japanese oak wilt, from Cyclorhipidion ohnoi and Crossotarsus emancipatus in Taiwan, and (2) R. lauricola, the pathogen responsible for laurel wilt, from Ambrosiodmus lecontei in Florida. The results of this study show that Raffaelea and associated ophiostomatoid fungi have been poorly sampled and that future investigations on ambrosia beetle mycosymbionts should reveal a substantially increased diversity.

Robert Jankowiak - One of the best experts on this subject based on the ideXlab platform.

  • Seven new species of Graphilbum from conifers in Norway, Poland, and Russia.
    Mycologia, 2020
    Co-Authors: Robert Jankowiak, Halvor Solheim, Piotr Bilański, Seonju Marincowitz, Michael J. Wingfield
    Abstract:

    During surveys of insect-associated mycobiomes in Norway, Poland, and Russia, isolates with affinity to Graphilbum (Ophiostomatales, Ascomycota) were recovered. In this study, eight known Graphilbum species as well as the newly collected isolates were compared based on morphology and DNA sequence data for four gene regions. The results revealed seven new species, described here as G. acuminatum, G. carpaticum, G. curvidentis, G. furuicola, G. gorcense, G. interstitiale, and G. sexdentatum. In addition to these species, G. crescericum and G. sparsum were commonly found in Norway. All new species were recovered from conifers in association with bark beetles, cerambycid beetles, and weevils and were morphologically similar, predominantly with pesotum-like asexual morphs. Where sexual morphs were present, these were small ascomata with short necks and rod-shaped ascospores having hyaline sheaths. The results suggest that Graphilbum species are common members of the Ophiostomatales in conifer ecosystems.

  • Four new Ophiostoma species associated with conifer- and hardwood-infesting bark and ambrosia beetles from the Czech Republic and Poland
    Antonie Van Leeuwenhoek International Journal of General and Molecular Microbiology, 2019
    Co-Authors: Robert Jankowiak, Agnieszka Bosak, Piotr Bilański, Riikka Linnakoski, Beata Strzałka, Georg Hausner
    Abstract:

    Fungi under the order Ophiostomatales (Ascomycota) are known to associate with various species of bark beetles (Coleoptera: Curculionidae: Scolytinae). In addition this group of fungi contains many taxa that can impart blue-stain on sapwood and some are important tree pathogens. A recent survey that focussed on the diversity of the Ophiostomatales in the forest ecosystems of the Czech Republic and Poland uncovered four putative new species. Phylogenetic analyses of four gene regions (ITS1-5.8S-ITS2 region, s-tubulin, calmodulin, and translation elongation factor 1-α) indicated that these four species are members of the genus Ophiostoma. All four newly described species can be distinguished from each other and from closely related species based on DNA sequence comparisons, morphological characters, growth rates, and their insect associations. Based on this study four new taxa can be circumscribed and the following names are provided: Ophiostoma pityokteinis sp. nov., Ophiostoma rufum sp. nov., Ophiostoma solheimii sp. nov., and Ophiostoma taphrorychi sp. nov. O. rufum sp. nov. is a member of the Ophiostoma piceae species complex, while O. pityokteinis sp. nov. resides in a discrete lineage within Ophiostoma s. stricto. O. taphrorychi sp. nov. together with O. distortum formed a well-supported clade in Ophiostoma s. stricto close to O. pityokteinis sp. nov. O. solheimii sp. nov. groups within a currently undefined lineage A, which also includes Ophiostoma grandicarpum and Ophiostoma microsporum. This study highlights the need for more intensive surveys that should include additional countries of Central Europe, insect vectors and host tree species in order to elucidate Ophiostoma species diversity in this region.

  • Ophiostomatoid fungi associated with hardwood-infesting bark and ambrosia beetles in Poland: Taxonomic diversity and vector specificity
    Fungal Ecology, 2019
    Co-Authors: Robert Jankowiak, Beata Strzałka, Magdalena Kacprzyk, Piotr Bilański, Piotr Wieczorek, Riikka Linnakoski
    Abstract:

    Abstract Fungi in the orders Ophiostomatales and Microascales (Ascomycota), often designated as ophiostomatoid fungi, are frequent associates of scolytine bark and ambrosia beetles that colonize hardwood and coniferous trees. Several species, e.g., Ophiostoma novo-ulmi, are economically damaging pathogens of trees. Because little is known regarding the ophiostomatoid fungi in Europe, we have explored the diversity of these fungi associated with hardwood-infesting beetles in Poland. This study aims to clarify the associations between fungi in the genera Ambrosiella, Graphium (Microascales), Graphilbum, Leptographium, Ophiostoma and Sporothrix (Ophiostomatales) and their beetle vectors in hardwood ecosystems. Samples associated with 18 bark and ambrosia beetle species were collected from 11 stands in Poland. Fungi were isolated from adult beetles and galleries. Isolates were identified based on morphology, DNA sequence comparisons for five gene regions (ITS, LSU, sT, TEF 1-α, and CAL) and phylogenetic analyses. In total, 36 distinct taxa were identified, including 24 known and 12 currently unknown species. Several associations between fungi and bark and ambrosia beetles were recorded for the first time. In addition, associations between Dryocoetes alni, D. villosus, Hylesinus crenatus, Ernoporus tiliae, Pteleobius vittatus and ophiostomatoid fungi were reported for the first time, and Sporothrix eucastanea was reported for the first time outside of the USA. Among the species of Ophiostomatales, 14 species were in Ophiostoma s. l., two species were in Graphilbum, nine species were in Sporothrix, and seven species were in Leptographium s. l. Among the species of Microascales, three species were in Graphium, and one was in Ambrosiella. Twenty taxa were present on the beetles and in the galleries, twelve only on beetles, and four only in galleries. Bark and ambrosia beetles from hardwoods appear to be regular vectors, with ophiostomatoid fungi present in all the beetle species. Most ophiostomatoid species had a distinct level of vector/host specificity, although Ophiostoma quercus, the most frequently encountered species, also had the greatest range of beetle vectors and tree hosts. Plant pathogenic O. novo-ulmi was found mainly in association with elm-infesting bark beetles (Scolytus multistriatus, S. scolytus, and P. vittatus) and occasionally with H. crenatus on Fraxinus excelsior and with Scolytus intricatus on Quercus robur.

  • Ophiostomatales associated with wounds on hardwood trees in Poland
    Plant Pathology, 2019
    Co-Authors: Robert Jankowiak, Piotr Bilański, A. Ostafińska, Riikka Linnakoski
    Abstract:

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  • Three new Leptographium spp. (Ophiostomatales) infecting hardwood trees in Norway and Poland
    Antonie van Leeuwenhoek, 2018
    Co-Authors: Robert Jankowiak, Agnieszka Ostafińska, Piotr Bilański, Riikka Linnakoski, Halvor Solheim, Georg Hausner
    Abstract:

    Species of Leptographium are characterized by mononematous or synnematous conidiophores and are commonly associated with different arthropods. Some of them also produce a sexual state characterised by globose ascomata with elongated necks. Compared to investigations on coniferous trees, the occurrence of Leptographium species on hardwood trees has been poorly studied in Europe. During a survey of ophiostomatoid fungi on various hardwood tree species in Norway and Poland, three unusual species, which fit in the broader morphological description of Leptographium spp., were found in association with Trypodendron domesticum , Trypodendron signatum and Dryocoetes alni , and from wounds on a variety of hardwoods. Phylogenetic analyses of sequence data for six different loci (ITS1–5.8 S–ITS2, ITS2-LSU, ACT, β-tubulin, CAL, and TEF-1α) showed that these Leptographium species are phylogenetically closely related to the species of the Grosmannia olivacea complex. The first species forms a well-supported lineage that includes Ophiostoma brevicolle , while the two other new taxa resided in a separate lineage; possibly affiliated with Grosmannia francke - grosmanniae . All the new species produce perithecia with necks terminating in ostiolar hyphae and orange-section shaped ascospores with cucullate, gelatinous sheaths. These species also produce dark olivaceous mononematous asexual states in culture. In addition, two of the newly described species have a second type of conidiophore with a short and non-pigmented stipe. The new Leptographium species can be easily distinguished from each other by their appearance and growth in culture. Based on novel morphological characters and distinct DNA sequences, these fungi were recognised as new taxa for which the names Leptographium tardum sp. nov., Leptographium vulnerum sp. nov., and Leptographium flavum sp. nov. are provided.

Léanne L. Dreyer - One of the best experts on this subject based on the ideXlab platform.

  • Wounds on Rapanea melanophloeos provide habitat for a large diversity of Ophiostomatales including four new species
    Antonie van Leeuwenhoek, 2016
    Co-Authors: Tendai Musvuugwa, Léanne L. Dreyer, Z. Wilhelm Beer, Tuan A. Duong, Kenneth Oberlander, Francois Roets
    Abstract:

    Rapanea melanophloeos , an important canopy tree in Afromontane forests, is commonly utilised for medicinal bark harvesting. Wounds created from these activities provide entrance for many fungi, including arthropod-associated members of the Ophiostomatales and Microascales (ophiostomatoid fungi). In this study we assessed the diversity of wound-associated Ophiostomatales on storm-damaged R. melanophloeos trees in the Afromontane forests of South Africa. Five species were identified based on micro-morphological and molecular phylogenetic analyses. These included Ophiostoma stenoceras and four newly described taxa Sporothrix itsvo sp. nov., S. rapaneae sp. nov., S. uta sp. nov. and O. noisomeae sp. nov. Four of these are members of the S. schenckii – O. stenoceras complex ( O. stenoceras , S. itsvo sp. nov., S . rapaneae sp. nov., S . uta sp. nov.) while O. noisomeae groups basal in the Ophiostomatales alongside the S. lignivora complex and Graphilbum . In addition to other taxa known from this host, the present study shows that there is a rich, yet still poorly explored, diversity of Ophiostomatales associated with R. melanophloeos in Afromontane forests. More taxa are likely to be discovered with increased research effort. These must be assessed in terms of pathogenicity towards this ecologically and economically important tree.

  • Future danger posed by fungi in the Ophiostomatales when encountering new hosts
    Fungal Ecology, 2016
    Co-Authors: Tendai Musvuugwa, Léanne L. Dreyer, Francois Roets
    Abstract:

    The authors thank the DST/NRF Centre of Excellence in Tree Health Biotechnology (CHTB) for financial support and the South African National Parks Board (SANPARKS) and Western Cape Nature Conservation Board for issuing the necessary collecting permits.

  • New species of Ophiostomatales from Scolytinae and Platypodinae beetles in the Cape Floristic Region, including the discovery of the sexual state of Raffaelea
    Antonie van Leeuwenhoek, 2015
    Co-Authors: Tendai Musvuugwa, Léanne L. Dreyer, Z. Wilhelm Beer, Tuan A. Duong, Kenneth C. Oberlander, Francois Roets
    Abstract:

    Olea capensis and Rapanea melanophloeos are important canopy trees in South African Afromontane forests. Dying or recently dead individuals of these trees are often infested by Scolytinae and Platypodinae (Curculionidae) beetles. Fungi were isolated from the surfaces of beetles emerging from wood samples and their galleries. Based on micro-morphological and phylogenetic analyses, four fungal species in the Ophiostomatales were isolated. These were Sporothrix pallida and three taxa here newly described as Sporothrix aemulophila sp. nov., Raffaelea vaginata sp. nov. and Raffaelea rapaneae sp. nov. This study represents the first collection of S. pallida , a species known from many environmental samples from across the world, from Scolytinae beetles. S. aemulophila sp. nov. is an associate of the ambrosia beetle Xyleborinus aemulus . R. rapaneae sp. nov. and R. vaginata sp. nov. were associated with a Lanurgus sp. and Platypodinae beetle, respectively, and represent the first Raffaelea spp. reported from the Cape Floristic Region. Of significance is that R. vaginata produced a sexual state analogous with those of Ophiostoma seticolle and O. deltoideosporum that also grouped in our analyses in Raffaelea s. str. , to date considered an asexual genus. The morphology of the ossiform ascospores and anamorphs of the three species corresponded and the generic circumscription of Raffaelea is thus emended to accommodate sexual states. The two known species are provided with new combinations, namely Raffaelea seticollis (R.W. Davidson) Z.W. de Beer and T.A. Duong comb. nov. and Raffaelea deltoideospora (Olchow. and J. Reid) Z.W. de Beer and T.A. Duong comb. nov.

  • two new ophiostoma species from protea caffra in zambia
    Persoonia, 2010
    Co-Authors: Francois Roets, Brenda D Wingfield, Z. Wilhelm Beer, Léanne L. Dreyer
    Abstract:

    The genus Ophiostoma (Ophiostomatales) has a global distribution and species are best known for their association with bark beetles (Curculionidae: Scolytinae) on conifers. An unusual assemblage of these fungi is closely associated with the African endemic plant genus Protea (Proteaceae). Protea-associated Ophiostoma species are ecologically atypical as they colonise the fruiting structures of various serotinous Protea species. Seven species have been described from this niche in South Africa. It has been speculated that novel species may be present in other African countries where these host plants also occur. This view was corroborated by recent col- lections of two unknown species from Protea caffra trees in Zambia. In the present study we evaluate the species delineation of these isolates using morphological comparisons with other Protea-associated species, differential growth studies and analyses of DNA sequence data for the β-tubulin and internal transcribed spacer (ITS1, 5.8S, ITS2) regions. As a result, the species O. protea­sedis sp. nov., and O. zambiensis sp. nov. are described here as new. This study brings the number of Protea-associated Ophiostoma species to nine and highlights the need for more inclusive surveys, including additional African countries and hosts, to elucidate species diversity in this uncharacteristic niche.

  • ophiostoma gemellus and sporothrix variecibatus from mites infesting protea infructescences in south africa
    Mycologia, 2008
    Co-Authors: Francois Roets, Wilhelm Z De Beer, Pedro W. Crous, Léanne L. Dreyer
    Abstract:

    Ophiostoma (Ophiostomatales) represents a large genus of fungi mainly known from associations with bark beetles (Curculionidae: Scolytinae) infest- ing conifers in the northern hemisphere. Few southern hemisphere native species are known, and the five species that consistently occur in the infructescences of Protea spp. in South Africa are ecologically unusual. Little is known about the vectors of Ophiostoma spp. from Protea infructescences, however recent studies have considered the possible role of insects and mites in the distribution of these exceptional fungi. In this study we describe a new species of Ophiostoma and a new Sporothrix spp. with affinities to Ophiostoma, both initially isolated from mites associated with Protea spp. They are described as Ophiostoma gemellus sp. nov. and Sporothrix variecibatus sp. nov. based on their morphology and comparisons of DNA sequence data of the 28S ribosomal, b-tubulin and internal transcribed spacer (ITS1, 5.8S, ITS2) regions. DNA sequences of S. variecibatus were identical to those of a Sporothrix isolate obtained from Eucalyptus leaf litter in the same area in which S. variecibatus occurs in Protea infructescences. Results of this study add evidence to the view that mites are the vectors of Ophiostoma spp. that colonize Protea infructescences. They also show that DNA sequence comparisons are likely to reveal