Publications by authors named "Marieka Gryzenhout"

27 Publications

  • Page 1 of 1

Phylogenomic analysis of a 55.1 kb 19-gene dataset resolves a monophyletic Fusarium that includes the Fusarium solani Species Complex.

Authors:
David M Geiser Abdullah Al-Hatmi Takayuki Aoki Tsutomu Arie Virgilio Balmas Irene Barnes Gary C Bergstrom M K K Bhattacharyya Cheryl L Blomquist Robert Bowden Balázs Brankovics Daren W Brown Lester William Burgess Kathryn Bushley Mark Busman José F Cano-Lira Joseph D Carrillo Hao-Xun Chang Chi-Yu Chen Wanquan Chen Martin I Chilvers Sofia Noemi Chulze Jeffrey J Coleman Christina A Cuomo Z Wilhelm de Beer G Sybren de Hoog Johanna Del Castillo-Múnera Emerson Del Ponte Javier Diéguez-Uribeondo Antonio Di Pietro Vérnonique Edel-Hermann Wade H Elmer Lynn Epstein Akif Eskalen Maria Carmela Esposto Kathryne L Everts Sylvia P Fernández-Pavía Gilvan Ferreira da Silva Nora A Foroud Gerda Fourie Rasmus J N Frandsen Stanley Freeman Michael Freitag Omer Frenkel Kevin K Fuller Tatiana Gagkaeva Donald Max Gardiner Anthony E Glenn Scott Gold Tom Gordon Nancy F Gregory Marieka Gryzenhout Josep Guarro Beth Gugino Santiago Gutiérrez Kim Hammond-Kosack Linda J Harris Mónika Homa Cheng-Fang Hong László Hornok Jenn-Wen Huang Macit Ilkit Adriaana Jacobs Karin Jacobs Cong Jiang Maria Del Mar Jimenez-Gasco Seogchan Kang Matthew T Kasson Kemal Kazan John Carlyle Kennell HyeSeon Kim Harold Corby Kistler Gretchen A Kuldau Tomasz Kulik Oliver Kurzai Imane Laraba Matthew H Laurence Theresa Yun Lee Yin-Won Lee Yong-Hwan Lee John F Leslie Edward C Y Liew Lily W Lofton Antonio Logrieco Manuel Sánchez López-Berges Alicia Graciela Luque Erik Lysøe Li-Jun Ma Robert E Marra Frank N Martin Sara Ruth May Susan McCormick Chyanna T McGee Jacques F Meis Quirico Migheli Nik Mohd Izham Mohamed Nor Michel Monod Antonio Moretti Diane Mostert Giuseppina Mulé Françoise Munaut Gary P Munkvold Paul Nicholson Marcio Nucci Kerry O'Donnell Matias Pasquali Ludwig H Pfenning Anna Prigitano Robert Proctor Stéphane Ranque Stephen Rehner Martijn Rep Gerardo Rodríguez-Alvarado Lindy J Rose Mitchell George Roth Carmen Ruiz-Roldán Amgad A Saleh Baharuddin Salleh Hyunkyu Sang Mercedes Scandiani Jonathan Scauflaire David Schmale Dylan Pg Short Adnan Šišić Jason Smith Christopher W Smyth Hokyoung Son Ellie Spahr Jason E Stajich Emma Steenkamp Christian Steinberg Rajagopal Subramaniam Haruhisa Suga Brett Anthony Summerell Antonella Susca Cassandra Lynn Swett Christopher Toomajian Terry Jarianna Torres-Cruz Anna Maria Tortorano Martin Urban Lisa J Vaillancourt Gary E Vallad Theo van der Lee Dan Vanderpool Anne D van Diepeningen Martha Vaughan Eduard Venter Marcele Vermeulen Paul E Verweij Altus Viljoen Cees Waalwijk Emma C Wallace Grit Walther Jie Wang Todd Ward Brian Wickes Nathan P Wiederhold Michael J Wingfield Ana K M Wood Jin-Rong Xu X B Yang Tapani Yli-Matilla Sung-Hwan Yun Latiffah Zakaria Hao Zhang Ning Zhang Sean Zhang Xue Zhang

Phytopathology 2020 Nov 17. Epub 2020 Nov 17.

Northwest Agriculture and Forestry University, 12469, College of Plant Protection, Yangling, Shaanxi, China;

Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. Previously (Geiser et al. 2013; Phytopathology 103:400-408. 2013), the Fusarium community voiced near unanimous support for a concept of Fusarium that represented a clade comprising all agriculturally and clinically important Fusarium species, including the F. solani Species Complex (FSSC). Subsequently, this concept was challenged by one research group (Lombard et al. 2015 Studies in Mycology 80: 189-245) who proposed dividing Fusarium into seven genera, including the FSSC as the genus Neocosmospora, with subsequent justification based on claims that the Geiser et al. (2013) concept of Fusarium is polyphyletic (Sandoval-Denis et al. 2018; Persoonia 41:109-129). Here we test this claim, and provide a phylogeny based on exonic nucleotide sequences of 19 orthologous protein-coding genes that strongly support the monophyly of Fusarium including the FSSC. We reassert the practical and scientific argument in support of a Fusarium that includes the FSSC and several other basal lineages, consistent with the longstanding use of this name among plant pathologists, medical mycologists, quarantine officials, regulatory agencies, students and researchers with a stake in its taxonomy. In recognition of this monophyly, 40 species recently described as Neocosmospora were recombined in Fusarium, and nine others were renamed Fusarium. Here the global Fusarium community voices strong support for the inclusion of the FSSC in Fusarium, as it remains the best scientific, nomenclatural and practical taxonomic option available.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1094/PHYTO-08-20-0330-LEDOI Listing
November 2020

High genetic diversity of spider species in a mosaic montane grassland landscape.

PLoS One 2020 8;15(6):e0234437. Epub 2020 Jun 8.

Department of Zoology and Entomology, University of the Free State Qwaqwa Campus, Phuthaditjhaba, Free State, South Africa.

Gene flow and genetic variation were examined within and among populations of five of the most common spider species in shrublands of the mountainous Golden Gate Highlands National Park (GGHNP), South Africa. These species included three active hunters, Dendryphantes purcelli Peckham & Peckham, 1903 (Salticidae), Pherecydes tuberculatus O.P.-Cambridge, 1883 (Thomisidae) and Philodromus browningi Lawrence, 1952 (Philodromidae), and two web-builders, Neoscona subfusca (C.L. Koch, 1837) (Araneidae) and a Theridion Walckenaer, 1802 species (Theridiidae). A total of 249 spiders (57 D. purcelli, 69 N. subfusca, 34 P. browningi, 56 P. tuberculatus and 33 Theridion sp.) were collected and analysed from six shrubland localities in the park. Analyses of sequence variation of the mitochondrial cytochrome oxidase c subunit I (COI) gene for each species revealed relatively low nucleotide diversity (π < 0.0420) but high genetic diversity (Hd > 0.6500) within populations for all species, except P. tuberculatus. Genetic differentiation was also noted to differ between species, with only P. tuberculatus indicating very large divergence (Fst > 0.2500). These results were reflected by gene flow, with D. purcelli, N. subfusca and the Theridion sp. estimated as experiencing more than one disperser per generation. Overall, highest gene flow was found in the two web-building species, indicating possible high dispersal ability of these spiders in the GGHNP. Additionally, constructed phylogenies indicated possible cryptic speciation occurring in the majority of the investigated species. Our current results indicate that the five investigated spider species were able to maintain gene flow between shrubland populations within the GGHNP to some degree, despite the mountainous landscape. However, further analyses incorporating additional molecular markers are needed to properly determine the extent of genetic diversity and gene flow of these species within the GGHNP.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0234437PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7279597PMC
August 2020

A first checklist of macrofungi for South Africa.

MycoKeys 2020 5;63:1-48. Epub 2020 Feb 5.

Department of Genetics, University of the Free State, Bloemfontein, PO Box 339, Bloemfontein 9300, Republic of South Africa University of the Free State Bloemfontein South Africa.

Macrofungi are considered as organisms that form large fruiting bodies above or below the ground that are visible without the aid of a microscope. These fungi include most basidiomycetes and a small number of ascomycetes. Macrofungi have different ecological roles and uses, where some are edible, medicinal, poisonous, decomposers, saprotrophs, predators and pathogens, and they are often used for innovative biotechnological, medicinal and ecological applications. However, comprehensive checklists, and compilations on the diversity and distribution of mushrooms are lacking for South Africa, which makes regulation, conservation and inclusion in national biodiversity initiatives difficult. In this review, we compiled a checklist of macrofungi for the first time (excluding lichens). Data were compiled based on available literature in journals, books and fungorium records from the National Collection of Fungi. Even if the list is not complete due to numerous unreported species present in South Africa, it still represents an overview of the current knowledge of the macromycetes of South Africa. The list of names enables the assessment of gaps in collections and knowledge on the fungal biodiversity of South Africa, and downstream applications such as defining residency status of species. It provides a foundation for new names to be added in future towards developing a list that will be as complete as possible, and that can be used by a wide audience including scientists, authorities and the public.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3897/mycokeys.63.36566DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7015970PMC
February 2020

Multiple Phytophthora species associated with a single riparian ecosystem in South Africa.

Mycologia 2015 Sep-Oct;107(5):915-25. Epub 2015 Aug 3.

Department of Plant Sciences, University of the Free State, Bloemfontein 9300, South Africa.

The diversity of Phytophthora spp. in rivers and riparian ecosystems has received considerable international attention, although little such research has been conducted in South Africa. This study determined the diversity of Phytophthora spp. within a single river in Gauteng province of South Africa. Samples were collected over 1 y including biweekly river baiting with Rhododendron indicum leaves. Phytophthora isolates were identified with phylogenetic analyses of sequences for the internal transcribed spacer (ITS) region of the ribosomal DNA and the mitochondrial cytochrome oxidase c subunit I (coxI) gene. Eight Phytophthora spp. were identified, including a new taxon, P. taxon Sisulu-river, and two hybrid species from Cooke's ITS clade 6. Of these, species from Clade 6 were the most abundant, including P. chlamydospora and P. lacustris. Species residing in Clade 2 also were encountered, including P. multivora, P. plurivora and P. citrophthora. The detection of eight species in this investigation of Phytophthora diversity in a single riparian river ecosystem in northern South Africa adds to the known diversity of this genus in South Africa and globally.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3852/13-380DOI Listing
November 2015

Recommendations of generic names in Diaporthales competing for protection or use.

IMA Fungus 2015 Jun 4;6(1):145-54. Epub 2015 Jun 4.

Department of Natural Sciences, Findlay University, Findlay, Ohio 45840 USA.

In advancing to one name for fungi, this paper treats generic names competing for use in the order Diaporthales (Ascomycota, Sordariomycetes) and makes a recommendation for the use or protection of one generic name among synonymous names that may be either sexually or asexually typified. A table is presented that summarizes these recommendations. Among the genera most commonly encountered in this order, Cytospora is recommended over Valsa and Diaporthe over Phomopsis. New combinations are introduced for the oldest epithet of important species in the recommended genus. These include Amphiporthe tiliae, Coryneum lanciforme, Cytospora brevispora, C. ceratosperma, C. cinereostroma, C. eugeniae, C. fallax, C. myrtagena, Diaporthe amaranthophila, D. annonacearum, D. bougainvilleicola, D. caricae-papayae, D. cocoina, D. cucurbitae, D. juniperivora, D. leptostromiformis, D. pterophila, D. theae, D. vitimegaspora, Mastigosporella georgiana, Pilidiella angustispora, P. calamicola, P. pseudogranati, P. stromatica, and P. terminaliae.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5598/imafungus.2015.06.01.09DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4500080PMC
June 2015

Bioactive compounds from the endophytic fungus Fusarium proliferatum.

Nat Prod Res 2016 Jun 9;30(11):1301-4. Epub 2015 Jul 9.

b Department of Chemistry , University of Venda , P/Bag X5050, Thohoyandou 0950 , South Africa.

The crude extract of an endophytic fungus isolated from Syzygium cordatum and identified as Fusarium proliferatum showed 100% cytotoxicity against the brine shrimp Artemia salina at 100 μg/mL. Seven coloured, biologically active metabolites - including ergosta-5,7,22-trien-3β-ol, nectriafurone-8-methyl ether, 9-O-methyl fusarubin, bostrycoidin, bostrycoidin-9-methyl ether and 8-hydroxy-5,6-dimethoxy-2-methyl-3-(2-oxo-propyl)-1,4-naphthoquinone- were isolated from the extract.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/14786419.2015.1053089DOI Listing
June 2016

Finding needles in haystacks: linking scientific names, reference specimens and molecular data for Fungi.

Authors:
Conrad L Schoch Barbara Robbertse Vincent Robert Duong Vu Gianluigi Cardinali Laszlo Irinyi Wieland Meyer R Henrik Nilsson Karen Hughes Andrew N Miller Paul M Kirk Kessy Abarenkov M Catherine Aime Hiran A Ariyawansa Martin Bidartondo Teun Boekhout Bart Buyck Qing Cai Jie Chen Ana Crespo Pedro W Crous Ulrike Damm Z Wilhelm De Beer Bryn T M Dentinger Pradeep K Divakar Margarita Dueñas Nicolas Feau Katerina Fliegerova Miguel A García Zai-Wei Ge Gareth W Griffith Johannes Z Groenewald Marizeth Groenewald Martin Grube Marieka Gryzenhout Cécile Gueidan Liangdong Guo Sarah Hambleton Richard Hamelin Karen Hansen Valérie Hofstetter Seung-Beom Hong Jos Houbraken Kevin D Hyde Patrik Inderbitzin Peter R Johnston Samantha C Karunarathna Urmas Kõljalg Gábor M Kovács Ekaphan Kraichak Krisztina Krizsan Cletus P Kurtzman Karl-Henrik Larsson Steven Leavitt Peter M Letcher Kare Liimatainen Jian-Kui Liu D Jean Lodge Janet Jennifer Luangsa-ard H Thorsten Lumbsch Sajeewa S N Maharachchikumbura Dimuthu Manamgoda María P Martín Andrew M Minnis Jean-Marc Moncalvo Giuseppina Mulè Karen K Nakasone Tuula Niskanen Ibai Olariaga Tamás Papp Tamás Petkovits Raquel Pino-Bodas Martha J Powell Huzefa A Raja Dirk Redecker J M Sarmiento-Ramirez Keith A Seifert Bhushan Shrestha Soili Stenroos Benjamin Stielow Sung-Oui Suh Kazuaki Tanaka Leho Tedersoo M Teresa Telleria Dhanushka Udayanga Wendy A Untereiner Javier Diéguez Uribeondo Krishna V Subbarao Csaba Vágvölgyi Cobus Visagie Kerstin Voigt Donald M Walker Bevan S Weir Michael Weiß Nalin N Wijayawardene Michael J Wingfield J P Xu Zhu L Yang Ning Zhang Wen-Ying Zhuang Scott Federhen

Database (Oxford) 2014 30;2014. Epub 2014 Jun 30.

National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, USA, CBS-KNAW Fungal Biodiversity Centre, P.O. Box 85167, 3508 AD Utrecht, The Netherlands, Department of Pharmaceutical Sciences - Microbiology, Università degli Studi di Perugia, Perugia, Italy, Molecular Mycology Research Laboratory, Centre for Infectious Diseases and Microbiology, Marie Bashir Institute for Infectious Diseases and Biosecurity, Sydney Medical School-Westmead Hospital, The University of Sydney, Westmead Millennium Institute, Westmead, Australia, Department of Biological and Environmental Sciences, University of Gothenburg, Box 461, 405 30 Göteborg, Sweden, Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37920, USA, Illinois Natural History Survey, University of Illinois, 1816 South Oak Street, Champaign, IL 61820, USA, Mycology Section, Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3DS, UK, Natural History Museum, University of Tartu, 46 Vanemuise, 51014 Tartu, Estonia, Purdue University, Department of Botany and Plant Pathology, 915 W. State Street, West Lafayette, IN 47907, USA, Institute of Excellence in Fungal Research, and School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand, Imperial College London, Royal Botanic Gardens, Kew TW9 3DS, England, UK, Muséum National d'Histoire Naturelle, Dépt. Systématique et Evolution CP39, UMR7205, 12 Rue Buffon, F-75005 Paris, France, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, P. R. China, Departamento de Biología Vegetal II, Facultad de Farmacia, Universidad Complutense de Madrid, Madrid 28040, Spain, Senckenberg Museum of Natural History Görlitz, PF 300 154, 02806 Görlitz, Germany, Department of Microbiology and Plant Pathology, Forestry Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0001, South Africa, Real Jardín Botánico, RJB-CSIC,

DNA phylogenetic comparisons have shown that morphology-based species recognition often underestimates fungal diversity. Therefore, the need for accurate DNA sequence data, tied to both correct taxonomic names and clearly annotated specimen data, has never been greater. Furthermore, the growing number of molecular ecology and microbiome projects using high-throughput sequencing require fast and effective methods for en masse species assignments. In this article, we focus on selecting and re-annotating a set of marker reference sequences that represent each currently accepted order of Fungi. The particular focus is on sequences from the internal transcribed spacer region in the nuclear ribosomal cistron, derived from type specimens and/or ex-type cultures. Re-annotated and verified sequences were deposited in a curated public database at the National Center for Biotechnology Information (NCBI), namely the RefSeq Targeted Loci (RTL) database, and will be visible during routine sequence similarity searches with NR_prefixed accession numbers. A set of standards and protocols is proposed to improve the data quality of new sequences, and we suggest how type and other reference sequences can be used to improve identification of Fungi. Database URL: http://www.ncbi.nlm.nih.gov/bioproject/PRJNA177353.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/database/bau061DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4075928PMC
February 2015

Botryosphaeriaceae species overlap on four unrelated, native South African hosts.

Fungal Biol 2014 Feb 3;118(2):168-79. Epub 2013 Dec 3.

Department of Plant Sciences, University of the Free State, Bloemfontein, South Africa.

Botryosphaeriaceae represents an important and diverse family of latent fungal pathogens of woody plants. We address the question of host range of these fungi by sampling leaves and branches of four native South African trees, including Acacia karroo (Fabaceae), Celtis africana (Cannabaceae), Searsia lancea (Anacardiaceae), and Gymnosporia buxifolia (Celastraceae). Two new species of the Botryosphaeriaceae, namely Tiarosporella africana sp. nov. and Aplosporella javeedii sp. nov. were identified, together with five known species, including Neofusicoccum parvum, Neofusicoccum kwambonambiense, Spencermartinsia viticola, Diplodia pseudoseriata, and Botryosphaeria dothidea. Most Botryosphaeriaceae occurred on more than one host. With the exception of S. lancea, which was infected by A. javeedii all the hosts were infected by more than one Botryosphaeriaceae species. Collectively, the results suggest that some intrinsic host factors, possibly combined with local environmental conditions, affect the distribution and co-infectivity of various hosts by the Botryosphaeriaceae. This would counteract the general ability of a species in the Botryosphaeriaceae to infect a broad range of plants. The combination of host and environmental factors might also explain why some Botryosphaeriaceae with apparently broad host ranges, are found on different suites of hosts in different areas of the world.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.funbio.2013.11.007DOI Listing
February 2014

Ion Torrent PGM as tool for fungal community analysis: a case study of endophytes in Eucalyptus grandis reveals high taxonomic diversity.

PLoS One 2013 16;8(12):e81718. Epub 2013 Dec 16.

Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.

The Kingdom Fungi adds substantially to the diversity of life, but due to their cryptic morphology and lifestyle, tremendous diversity, paucity of formally described specimens, and the difficulty in isolating environmental strains into culture, fungal communities are difficult to characterize. This is especially true for endophytic communities of fungi living in healthy plant tissue. The developments in next generation sequencing technologies are, however, starting to reveal the true extent of fungal diversity. One of the promising new technologies, namely semiconductor sequencing, has thus far not been used in fungal diversity assessments. In this study we sequenced the internal transcribed spacer 1 (ITS1) nuclear encoded ribosomal RNA of the endophytic community of the economically important tree, Eucalyptus grandis, from South Africa using the Ion Torrent Personal Genome Machine (PGM). We determined the impact of various analysis parameters on the interpretation of the results, namely different sequence quality parameter settings, different sequence similarity cutoffs for clustering and filtering of databases for removal of sequences with incomplete taxonomy. Sequence similarity cutoff values only had a marginal effect on the identified family numbers, whereas different sequence quality filters had a large effect (89 vs. 48 families between least and most stringent filters). Database filtering had a small, but statistically significant, effect on the assignment of sequences to reference sequences. The community was dominated by Ascomycota, and particularly by families in the Dothidiomycetes that harbor well-known plant pathogens. The study demonstrates that semiconductor sequencing is an ideal strategy for environmental sequencing of fungal communities. It also highlights some potential pitfalls in subsequent data analyses when using a technology with relatively short read lengths.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0081718PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3864840PMC
September 2014

Surveys of soil and water reveal a goldmine of Phytophthora diversity in South African natural ecosystems.

IMA Fungus 2013 Jul 10;4(1):123-31. Epub 2013 Jun 10.

Department of Genetics and Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002, South Africa ; Current address: E-Planet Co. Ltd. 345-9 Gasandong Gumcheongu, 153-802, Seoul, Republic of Korea.

Phytophthora species are well-known as destructive plant pathogens, especially in natural ecosystems. It is ironic, therefore, how little is known regarding the Phytophthora diversity in South African natural woody ecosystems. In this study, Phytophthora species were isolated using standard baiting techniques from 182 soil and water samples and these were identified based on ITS and coxI sequence data. The 171 resulting Phytophthora isolates resided in 14 taxa including six known species (P. multivora, P. capensis, P. cryptogea, P. frigida, P. cinnamomi, P. cinnamomi var. parvispora), the known but as yet unnamed Phytophthora sp. PgChlamydo, P. sp. emzansi, and P. sp. Kununurra and five novel taxa referred to as P. sp. stellaris, P. sp. Umtamvuna P. sp. canthium, P. sp. xWS, P. sp. xHennops. Four of the new taxa were found exclusively in water and two of these are hybrids. The most commonly isolated species from soil was P. multivora, a species recently described from Western Australia. Phytophthora frigida was isolated for the first time from stream water. With the exception of P. cinnamomi, very little is known regarding the biology, epidemiology or origin of Phytophthora in South Africa.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5598/imafungus.2013.04.01.12DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3719200PMC
July 2013

Characterization of Phytophthora hybrids from ITS clade 6 associated with riparian ecosystems in South Africa and Australia.

Fungal Biol 2013 May 29;117(5):329-47. Epub 2013 Mar 29.

Department of Genetics, Forestry and Agricultural Biotechnology Institute, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria 0002, South Africa.

Surveys of Australian and South African rivers revealed numerous Phytophthora isolates residing in clade 6 of the genus, with internal transcribed spacer (ITS) gene regions that were either highly polymorphic or unsequenceable. These isolates were suspected to be hybrids. Three nuclear loci, the ITS region, two single copy loci (antisilencing factor (ASF) and G protein alpha subunit (GPA)), and one mitochondrial locus (cytochrome oxidase c subunit I (coxI)) were amplified and sequenced to test this hypothesis. Abundant recombination within the ITS region was observed. This, combined with phylogenetic comparisons of the other three loci, confirmed the presence of four different hybrid types involving the three described parent species Phytophthora amnicola, Phytophthora thermophila, and Phytophthora taxon PgChlamydo. In all cases, only a single coxI allele was detected, suggesting that hybrids arose from sexual recombination. All the hybrid isolates were sterile in culture and all their physiological traits tended to resemble those of the maternal parents. Nothing is known regarding their host range or pathogenicity. Nonetheless, as several isolates from Western Australia were obtained from the rhizosphere soil of dying plants, they should be regarded as potential threats to plant health. The frequent occurrence of the hybrids and their parent species in Australia strongly suggests an Australian origin and a subsequent introduction into South Africa.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.funbio.2013.03.004DOI Listing
May 2013

Species delineation in the tree pathogen genus Celoporthe (Cryphonectriaceae) in southern Africa.

Mycologia 2013 Mar-Apr;105(2):297-311. Epub 2012 Dec 11.

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Private Bag X20, Hatfield, Pretoria, 0028, South Africa.

The genus Celoporthe was first described when C. dispersa was discovered in South Africa associated with dieback and cankers on trees in the Myrtales. Four additional species were recently described from Eucalyptus and Syzygium cumini in China as well as S. aromaticum and Eucalyptus in Indonesia. Inoculation trials have shown that all Celoporthe species, including those that have not been found on Eucalyptus species in nature, are pathogenic to Eucalyptus and they are thus potentially threatening to commercial Eucalyptus forestry. New isolates, morphologically similar to Celoporthe, have been collected from S. legatti in South Africa and S. guineense in Zambia. Multigene phylogenetic analyses based on DNA sequences of the ITS region, TEF1α gene and two areas of the β-tubulin gene revealed additional cryptic species in Celoporthe. Phylogenetic data were supported by morphological differences. These resulted in the description of two previously unknown species of Celoporthe, namely C. fontana and C. woodiana, for two of these cryptic groups, while the third group represented C. dispersa. These species all can readily infect Eucalyptus as well as several species of Syzygium, the latter of which are native to Africa.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3852/12-206DOI Listing
June 2014

The status of mycology in Africa: A document to promote awareness.

IMA Fungus 2012 Jun 27;3(1):99-102. Epub 2012 Jun 27.

Department of Plant Sciences, University of the Free State, Bloemfontein, South Africa, 9301.

The African Mycological Association (AMA) promotes mycology amongst members in Africa and globally. The AMA has about 200 members, mostly from African states but also with strong representation from Europe and USA, amongst others. Recent efforts by members of the AMA focused on reviving and developing mycological research and networking in Africa. A great deal must, however, still be done to promote the AMA under African mycologists, and those elsewhere with interests in Africa. African mycologists also experience challenges typical of the developing world and a great deal of fungi still needs to be discovered. This can also be seen as representing great opportunities for research and collaboration. Several issues pertinent to mycology in Africa were discussed during Special Interest Group sessions of the 9th International Mycological Congress in 2010, and through several opinion pieces contributed by AMA members in the AMA newsletter, MycoAfrica. This contribution serves as a document to summarise these in a form that can be presented to fellow mycologists, biologists and other scientists, relevant government departments, funding bodies and Non-Governmental Organizations and that pins down the importance of mycology, the status thereof in Africa and the need to promote it more.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.5598/imafungus.2012.03.01.11DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3399108PMC
June 2012

Novel species of Celoporthe from Eucalyptus and Syzygium trees in China and Indonesia.

Mycologia 2011 Nov-Dec;103(6):1384-410. Epub 2011 Jun 23.

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria 0002, South Africa.

Many species in the Cryphonectriaceae cause diseases of trees, including those in the genera Eucalyptus and Syzygium. During disease surveys on these trees in southern China, fruiting structures typical of fungi in the Cryphonectriaceae and associated with dying branches and stems were observed. Morphological comparisons suggested that these fungi were distinct from the well known Chrysoporthe deuterocubensis, also found on these trees in China. The aim of this study was to identify these fungi and evaluate their pathogenicity to Eucalyptus clones/species as well as Syzygium cumini. Three morphologically similar fungal isolates collected previously from Indonesia also were included in the study. Isolates were characterized based on comparisons of morphology and DNA sequence data for the partial LSU and ITS nuclear ribosomal DNA, β-tubulin and TEF-1α gene regions. After glasshouse trials to select virulent isolates field inoculations were undertaken to screen different commercial Eucalyptus clones/species and S. cumini trees for susceptibility to infection. Phylogenetic analyses showed that the Chinese isolates and those from Indonesia reside in a clade close to previously identified South African Celoporthe isolates. Based on morphology and DNA sequence comparisons, four new Celoporthe spp. were identified and they are described as C. syzygii, C. eucalypti, C. guangdongensis and C. indonesiensis. Field inoculations indicated that the three Chinese Celoporthe spp., C. syzygii, C. eucalypti and C. guangdongensis, are pathogenic to all tested Eucalyptus and S. cumini trees. Significant differences in the susceptibility of the inoculated Eucalyptus clones/species suggest that it will be possible to select disease-tolerant planting stock for forestry operations in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3852/11-006DOI Listing
January 2012

New records of the Cryphonectriaceae from southern Africa including Latruncellus aurorae gen. sp. nov.

Mycologia 2011 May-Jun;103(3):554-69. Epub 2011 Jan 24.

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), Private Bag X20, University of Pretoria, Pretoria 0002, South Africa.

The Cryphonectriaceae accommodates some of the world's most important tree pathogens, including four genera known from native and introduced Myrtales in Africa. Surveys in the past 3 y in southern Africa have led to the discovery of cankers with fruiting structures resembling those of the Cryphonectriaceae on trees in the Myrtales in Namibia, South Africa, Swaziland and Zambia. These fungi were identified with morphological characteristics and DNA sequence data. For the first time we report Chrysoporthe austroafricana from Namibia and on Syzygium guineense and Holocryphia eucalypti in Swaziland on a Eucalyptus grandis clone. The host and geographic ranges of Celoporthe dispersa are expanded to include S. legatti in South Africa and S. guineense in Zambia. In addition a monotypic genus, Latruncellus aurorae gen. sp. nov., is described from Galpinia transvaalica (Lythraceae, Myrtales) in Swaziland. The present and other recent studies clearly emphasize the limited understanding of the diversity and distribution of fungi in the Cryphonectriaceae in Africa.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3852/10-283DOI Listing
September 2011

Multigene phylogenetic and population differentiation data confirm the existence of a cryptic species within Chrysoporthe cubensis.

Fungal Biol 2010 Nov-Dec;114(11-12):966-79. Epub 2010 Oct 8.

Department of Genetics, University of Pretoria, Pretoria, South Africa.

Chrysoporthe cubensis is one of the most important pathogens of Eucalyptus. Based on phylogenetic evidence and geographic origin, isolates of this fungus are known to reside in distinct 'South America' and 'Southeast Asia' clades. In this study, reproductive isolation amongst these isolates of C. cubensis was tested using gene flow statistics for 12 polymorphic loci, and to support these data, phylogenetic affiliations based on gene trees and a multigene phylogeny were used. Gene flow statistics between populations, and relative to the closely related Chrysoporthe austroafricana, were low and not significantly different (P<0.05). Additionally, phylogenetic analyses of DNA sequence data for four gene regions convincingly distinguished the two subclades of C. cubensis. Isolates in the Southeast Asian subclade are described in the new species, Chrysoporthe deuterocubensis. Chrysoporthe cubensis and C. deuterocubensis represent closely related fungi that are thought to be native to South America and Southeast Asia, respectively. A technique is presented that allows for rapid differentiation between these species and that will aid in quarantine procedures to limit their spread to new environments.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.funbio.2010.09.007DOI Listing
February 2011

AFLP analysis reveals a clonal population of Phytophthora pinifolia in Chile.

Fungal Biol 2010 Sep 8;114(9):746-52. Epub 2010 Jul 8.

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002, South Africa.

Phytophthora pinifolia is the causal agent of the recently discovered needle disease of Pinus radiata in Chile, referred to as "Daño Foliar del Pino" (DFP). The genetic structure of the pathogen population is unknown, which hinders our understanding of its appearance and spread in Chile since 2004. In this study, a population of 88 cultures of P. pinifolia isolated from P. radiata at several localities in Chile was evaluated for genotypic diversity using amplified fragment length polymorphisms (AFLPs). Results of the AFLP analyses showed that the P. pinifolia population in Chile consists of two near identical genotypes but with no genetic differentiation based on geography, year of isolation or the part of the tree from which the isolates were obtained. Mating experiments did not lead to the production of gametangia suggesting that the organism is sterile. The fact that a single clonal genotype dominates the population of P. pinifolia in Chile supports the hypothesis that P. pinifolia was recently introduced into this country and that its impact is due to a new and susceptible host encounter.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.funbio.2010.06.008DOI Listing
September 2010

Aurifilum, a new fungal genus in the Cryphonectriaceae from Terminalia species in Cameroon.

Antonie Van Leeuwenhoek 2010 Oct 18;98(3):263-78. Epub 2010 Jun 18.

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002, South Africa.

Native Terminalia spp. in West Africa provide a popular source of construction timber as well as medical, spiritual and social benefits to rural populations. Very little is, however, known regarding the diseases that affect these trees. During an investigation into possible diseases of Terminalia spp. in Cameroon, orange to yellow fungal fruiting structures, resembling those of fungi in the Cryphonectriaceae, were commonly observed on the bark of native Terminalia ivorensis, and on dead branches of non-native Terminalia mantaly. In this study the fungus was identified based on morphological features as well as DNA sequence data (ITS and beta-tubulin) and its pathogenicity was tested on T. mantaly seedlings. Our results showed that isolates of this fungus represent a previously undescribed genus in the Cryphonectriaceae, which we describe as Aurifilum marmelostoma gen. et sp. nov. Pathogenicity tests revealed that A. marmelostoma is pathogenic on T. mantaly. These tests, and the association of A. marmelostoma with disease symptoms on T. ivorensis, suggest that the fungus is a pathogen of this important tree.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10482-010-9467-8DOI Listing
October 2010

DNA-based method for rapid identification of the pine pathogen, Phytophthora pinifolia.

FEMS Microbiol Lett 2009 Sep 22;298(1):99-104. Epub 2009 Jun 22.

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.

Phytophthora pinifolia causes a needle and shoot disease in Pinus radiata, referred to as 'Daño Foliar del Pino'. This newly discovered disease requires intensive research efforts that necessitate the processing of large numbers of samples for which accurate identification, often by people not experienced in Phytophthora taxonomy, is required. The aim of this study was, therefore, to develop species-specific primers for P. pinifolia that amplify the internal transcribed spacer region of the ribosomal operon and the nuclear Ypt1 gene, respectively. The primers were tested over several Phytophthora spp., as well as fungi isolated from P. radiata. In all cases, only P. pinifolia was amplified. In addition to the species-specific primers, a PCR-restriction fragment length polymorphism protocol using available Phytophthora genus-specific primers was also used to generate a species-specific profile for P. pinifolia. This provided a characteristic profile that allows the identification of P. pinifolia, and it could also discriminate between 27 different species of Phytophthora. Both techniques reported in this study make it possible to identify large numbers of P. pinifolia cultures accurately and efficiently, which will be important for both quarantine work and biological research on this important new pathogen.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1574-6968.2009.01700.xDOI Listing
September 2009

The Ascomycota tree of life: a phylum-wide phylogeny clarifies the origin and evolution of fundamental reproductive and ecological traits.

Syst Biol 2009 Apr 4;58(2):224-39. Epub 2009 Jun 4.

Department of Botany and Plant Pathology, Oregon State University, Corvallis, OR 97331, USA.

We present a 6-gene, 420-species maximum-likelihood phylogeny of Ascomycota, the largest phylum of Fungi. This analysis is the most taxonomically complete to date with species sampled from all 15 currently circumscribed classes. A number of superclass-level nodes that have previously evaded resolution and were unnamed in classifications of the Fungi are resolved for the first time. Based on the 6-gene phylogeny we conducted a phylogenetic informativeness analysis of all 6 genes and a series of ancestral character state reconstructions that focused on morphology of sporocarps, ascus dehiscence, and evolution of nutritional modes and ecologies. A gene-by-gene assessment of phylogenetic informativeness yielded higher levels of informativeness for protein genes (RPB1, RPB2, and TEF1) as compared with the ribosomal genes, which have been the standard bearer in fungal systematics. Our reconstruction of sporocarp characters is consistent with 2 origins for multicellular sexual reproductive structures in Ascomycota, once in the common ancestor of Pezizomycotina and once in the common ancestor of Neolectomycetes. This first report of dual origins of ascomycete sporocarps highlights the complicated nature of assessing homology of morphological traits across Fungi. Furthermore, ancestral reconstruction supports an open sporocarp with an exposed hymenium (apothecium) as the primitive morphology for Pezizomycotina with multiple derivations of the partially (perithecia) or completely enclosed (cleistothecia) sporocarps. Ascus dehiscence is most informative at the class level within Pezizomycotina with most superclass nodes reconstructed equivocally. Character-state reconstructions support a terrestrial, saprobic ecology as ancestral. In contrast to previous studies, these analyses support multiple origins of lichenization events with the loss of lichenization as less frequent and limited to terminal, closely related species.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/sysbio/syp020DOI Listing
April 2009

Celoporthe dispersa gen. et sp. nov. from native Myrtales in South Africa.

Stud Mycol 2006 ;55:255-67

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, 0002, South Africa.

In a survey for Cryphonectria and Chrysoporthe species on Myrtales in South Africa, a fungus resembling the stem canker pathogen Chrysoporthe austroafricana was collected from native Syzygium cordatum near Tzaneen (Limpopo Province), Heteropyxis canescens near Lydenburg (Mpumalanga Province) and exotic Tibouchina granulosa in Durban (KwaZulu-Natal Province). The fungus was associated with dying branches and stems on S. cordatum, H.canescens and T.granulosa. However, morphological differences were detected between the unknown fungus from these three hosts and known species of Chrysoporthe. The aim of this study was to characterise the fungus using DNA sequence comparisons and morphological features. Pathogenicity tests were also conducted to assess its virulence on Eucalyptus (ZG 14 clones), H.natalensis and T. granulosa. Plants of H. canescens were not available for inoculation. Results showed distinct morphological differences between the unknown fungus and Chrysoporthe spp. Phylogenetic analysis showed that isolates reside in a clade separate from Chrysoporthe and other related genera. Celoporthe dispersa gen. et sp. nov. is, therefore, described to accommodate this fungus. Pathogenicity tests showed that C.dispersa is not pathogenic to H. natalensis, but that it is a potential pathogen of Eucalyptus and Tibouchina spp.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2104720PMC
http://dx.doi.org/10.3114/sim.55.1.255DOI Listing
July 2011

Microthia, Holocryphia and Ursicollum, three new genera on Eucalyptus and Coccoloba for fungi previously known as Cryphonectria.

Stud Mycol 2006 ;55:35-52

Department of Microbiology and Plant Pathology; Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, 0002, South Africa.

Cryphonectria havanensis is a fungus associated with Eucalyptus species in Cuba and Florida (U.S.A.). Until recently, there have been no living cultures of C. havanensis and it has thus not been possible to assess its taxonomic status. Isolates thought to represent this fungus have, however, emerged from surveys of Eucalyptus in Mexico and Hawaii (U.S.A.). Results of this study showed that these isolates represent C. havanensis but reside in a genus distinct from Cryphonectria sensu stricto, which is described here as Microthia. Isolates of an unidentified fungus occurring on Myrica faya in the Azores and Madeira also grouped in Microthia and were identical to other M. havanensis isolates. Cryphonectria coccolobae, a fungus occurring on sea grape (Coccoloba uvifera) in Bermuda and Florida, was found to be morphologically identical to Microthia and is transferred to this genus, but as a distinct species. Surveys for M. coccolobae on sea grape in Florida, yielded a second diaporthalean fungus from this host. This fungus is morphologically and phylogenetically distinct from M. coccolobae and other closely related taxa and is described as Ursicollum fallax gen. et sp. nov. Phylogenetic analyses in this study have also shown that isolates of C. eucalypti, a pathogen of Eucalyptus in South Africa and Australia, group in a clade separate from all other groups including that representing Cryphonectria sensu stricto. This difference is supported by the fact that Cryphonectria eucalypti has ascospore septation different to that of all other Cryphonectria species. A new genus, Holocryphia, is thus erected for C. eucalypti.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2104726PMC
http://dx.doi.org/10.3114/sim.55.1.35DOI Listing
July 2011

Novel hosts of the Eucalyptus canker pathogen Chrysoporthe cubensis and a new Chrysoporthe species from Colombia.

Mycol Res 2006 Jul;110(Pt 7):833-45

Department of Microbiology and Plant Pathology, Tree Protection Co-operative Programme, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa.

The pathogen Chrysoporthe cubensis (formerly Cryphonectria cubensis) is best known for the important canker disease that it causes on Eucalyptus species. This fungus is also a pathogen of Syzygium aromaticum (clove), which is native to Indonesia, and like Eucalyptus, is a member of Myrtaceae. Furthermore, C. cubensis has been found on Miconia spp. native to South America and residing in Melastomataceae. Recent surveys have yielded C. cubensis isolates from new hosts, characterized in this study based on DNA sequences for the ITS and beta-tubulin gene regions. These hosts include native Clidemia sericea and Rhynchanthera mexicana (Melastomataceae) in Mexico, and non-native Lagerstroemia indica (Pride of India, Lythraceae) in Cuba. Isolates from these hosts and areas group in the sub-clade of C. cubensis accommodating the South American collections of the fungus. This sub-clade also includes isolates recently collected from Eucalyptus in Cuba, which are used to epitypify C. cubensis. New host records from Southeast Asia include exotic Tibouchina urvilleana from Singapore and Thailand and native Melastoma malabathricum (Melastomataceae) in Sumatra, Indonesia. Consistent with their areas of occurrence isolates from the latter collections group in the Asian sub-clade of C. cubensis. DNA sequence comparisons of isolates from Tibouchina lepidota in Colombia revealed that they represent a new sub-clade within the greater Chrysoporthe clade. Isolates in this clade are described as Chrysoporthe inopina sp. nov., based on distinctive morphological differences.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.mycres.2006.02.010DOI Listing
July 2006

Aurapex penicillata gen. sp. nov. from native Miconia theaezans and Tibouchina spp. in Colombia.

Mycologia 2006 Jan-Feb;98(1):105-15

Department of Microbiology and Plant Pathology, Forestry & Agricultural Biotechnology Institute, University of Pretoria, South Africa.

Conidiomata of a fungus resembling Chrysoporthe cubensis, a serious canker pathogen of Eucalyptus spp. (Myrtaceae, Myrtales) in tropical and subtropical parts of the world, was found on Eucalyptus grandis in Colombia. Fruiting structures of the fungus could be distinguished from those of C. cubensis by their distinctly orange conidiomatal necks. This fungus also was found on several plant species native to Colombia including Tibouchina urvilleana, T. lepidota and Miconia theaezans (Melastomataceae, Myrtales). Morphological comparisons, as well as those based on sequences of the ITS1/ITS2 region of the ribosomal DNA repeat and the beta-tubulin gene, were used to characterize this fungus. Its pathogenicity was assessed on various plants from which it has been collected, either in field or greenhouse trials. Phylogenetic analyses showed that isolates reside in a clade distinct from the four clades accommodating Chrysoporthe, Cryphonectria, Endothia and Rostraureum. Members of this clade are distinguished by the presence of orange conidiomatal necks with black bases and a unique internal stromatal structure. No teleomorph has been found for this fungus, for which we have provided the name Aurapex penicillata gen. sp. nov. A. penicillata produced only small lesions after inoculation on young T. urvilleana, M. theaezans and E. grandis trees and appears not to be a serious pathogen.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3852/mycologia.98.1.105DOI Listing
August 2006

New taxonomic concepts for the important forest pathogen Cryphonectria parasitica and related fungi.

FEMS Microbiol Lett 2006 May;258(2):161-72

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, South Africa.

Species of Cryphonectria include some of the world's most important and devastating tree pathogens. Largely through the application of DNA sequence phylogenies, the taxonomy of these fungi has undergone major changes in recent years. Cryphonectria, including the chestnut blight pathogen Cryphonectria parasitica, has been restricted to species that have semi-immersed stromata, orange and pulvinate conidiomata, and one-septate ascospores. Other species of Cryphonectria with different morphological characteristics have been transferred to new genera that are strongly supported by phylogenetic data. This review represents a summary of the taxonomic changes to species of Cryphonectria sensu lato, and we discuss the impact that these changes might have on the understanding of their ecology, pathology and worldwide distribution.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/j.1574-6968.2006.00170.xDOI Listing
May 2006

Rostraureum tropicale gen. sp. nov. (Diaporthales) associated with dying Terminalia ivorensis in Ecuador.

Mycol Res 2005 Sep;109(Pt 9):1029-44

Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria 0002, South Africa.

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.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1017/s0953756205003291DOI Listing
September 2005

Phylogenetic relationships of Cryphonectria and Endothia species, based on DNA sequence data and morphology.

Mycologia 2004 Sep-Oct;96(5):990-1001

Department of Genetics, Forestry and Agricultural, Biotechnology Institute (FABI), University of Pretoria, Pretoria, 0002, South Africa.

The fungal genera Endothia and Cryphonectria include some of the most important pathogens 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 Cryphonectria 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 β-tu-bulin gene. In addition, the morphology of these species was examined. The phylogenetic data indicated that Endothia and Cryphonectria reside in two distinct phylogenetic clades. Cryphonectria parasitica, C. macrospora, C. nitschkei, C. eucalypti and C. radicalis represented the Cryphonectria clade. Endothia gyrosa and E. singularis were included in the Endothia clade. An isolate representing E. viridistroma grouped outside the Endothia clade and separately from other groups. Other clades outside the one encompassing Cryphonectria were those represented by the C. cubensis isolates and fungi isolated from Elaeocarpus dentatus originating from New Zealand. These clades could be distinguished from Endothia and Cryphonectria, based on anamorph morphology, stromatal structure and ascospore septation. Cryphonectria and Endothia, therefore, appear to be paraphyletic and taxonomic relationships for these fungi need to be revised.
View Article and Find Full Text PDF

Download full-text PDF

Source
October 2012