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    Paraphoma chlamydocopiosa sp nov and Paraphoma pye sp nov., two new species associated with leaf and crown infection of pyrethrum
    Moslemi, A ; Ades, PK ; Crous, PW ; Groom, T ; Scott, JB ; Nicolas, ME ; Taylor, PWJ (WILEY, 2018-01)
    Two new pathogens of pyrethrum, described as Paraphoma chlamydocopiosa and Paraphoma pye, isolated from necrotic leaf lesions on pyrethrum plants in northern Tasmania, Australia, were identified using morphological characters, phylogenetic analysis of the internal transcribed spacer (ITS), elongation factor 1‐α (EF1‐α) and β‐tubulin (TUB) genes, and pathogenicity bioassays. Bootstrap support in the combined and individual gene region phylogenetic trees supported the two species that were significantly different from the closely related P. chrysanthemicola and P. vinacea. Morphological characteristics also supported the two new species, with conidia of P. chlamydocopiosa being considerably longer and wider than either P. chrysanthemicola or P. vinacea, and P. pye being distinct in forming bilocular pycnidia. Glasshouse pathogenicity tests based on root dip inoculation resulted in P. chlamydocopiosa and P. pye infecting the crown and upper root tissues of pyrethrum plants, and significant reduction in biomass 2 months after inoculation. Both of these Paraphoma species caused leaf lesions during in vitro and in vivo bioassays 2 weeks after foliar spray inoculation. Although P. chlamydocopiosa and P. pye were shown to be crown rot pathogens, they were also commonly isolated from leaves of diseased plants in pyrethrum fields of northern Tasmania.
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    Neotypification of Dothistroma septosporum and epitypification of D. pini, causal agents of Dothistroma needle blight of pine
    Barnes, I ; van der Nest, A ; Mullett, MS ; Crous, PW ; Drenkhan, R ; Musolin, DL ; Wingfield, MJ ; Woodward, S (WILEY, 2016-10)
    Summary Dothistroma needle blight (DNB) is one of the most devastating needle diseases on Pinus spp. worldwide. Ever since the description of the causal agent of the disease in Europe in 1911 as Cytosporina septospora, and independently in the USA in 1941 as Dothistroma pini, there has been considerable taxonomic discordance regarding the name of the pathogen used in literature. This was compounded both by the proposal of different varieties of the pathogen based on differences in spore size and the application of dual nomenclature where three names, Scirrhia pini, Eruptio pini and Mycosphaerella pini, were used to describe the sexual morph of the fungus. More recent studies using sequence‐based methods revealed that DNB can be caused by either one of two distinct species, that is D. septosporum and D. pini. These important species have not been adequately typified, and this perpetuates lack of stability for their names. In this study, these names are fixed to reference sequences linked to living cultures representing type specimens. To achieve this goal, we designate an epitype for D. pini and a neotype for D. septosporum. The known polymorphism in the ITS region, the barcoding gene for these fungi, is characterized and a complete taxonomic history is provided for the genus Dothistroma.
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    Colletotrichum species associated with chili anthracnose in Australia
    De Silva, DD ; Ades, PK ; Crous, PW ; Taylor, PWJ (WILEY, 2017-02)
    Phylogenetic relationships were determined for 45 Colletotrichum isolates causing anthracnose disease of chili in Queensland, Australia. Initial screening based on morphology, ITS and TUB2 genes resulted in a subset of 21 isolates being chosen for further taxonomic study. Isolates in the C. acutatum complex were analysed using partial sequences of six gene regions (ITS, GAPDH, ACT, CHS‐1, TUB2 and HIS3), and in the C. gloeosporioides complex were analysed using four gene regions (ITS, TUB2, ApMat and GS). Phylogenetic analysis delineated four Colletotrichum species including C. siamense, C. simmondsii, C. queenslandicum, C. truncatum and a new Colletotrichum species, described here as C. cairnsense sp. nov. This is the first reported association of C. queenslandicum, C. simmondsii and C. siamense with chili anthracnose in Australia; these species were previously associated with anthracnose on papaya and avocado. Furthermore, the dominant species causing anthracnose of chili in Southeast Asia, C. scovillei, was not detected in Australia. Inoculations on chili fruit confirmed the pathogenicity of C. cairnsense and the other four species in the development of chili anthracnose in Australia.
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    Tan spot of pyrethrum is caused by a Didymella species complex
    Pearce, TL ; Scott, JB ; Crous, PW ; Pethybridge, SJ ; Hay, FS (WILEY, 2016-09)
    Tan spot is a disease of pyrethrum (Tanacetum cinerariifolium) in Australia. Recent increases in the severity and incidence of the disease have prompted a re‐evaluation of the pathogen, originally described as Microsphaeropsis tanaceti, including its phylogenetic relationships and morphology. Nucleotide comparison of partial sequences of the nuclear ribosomal internal transcribed spacer, β‐tubulin, large subunit 28S nrDNA (LSU), actin and glyceraldehyde‐3‐phosphate dehydrogenase loci identified two distinct haplotypes within the species. Haplotype differentiation was consistent for each locus, except for the LSU, within which sequences were identical across all isolates. Morphological variation, especially culture pigmentation and conidial size, consistently supported the phylogenetic data distinguishing two haplotypes. Phylogenetic comparisons of M. tanaceti incorporating 98 Didymellaceae species did not associate the M. tanaceti haplotypes with the genus Microsphaeropsis. The two M. tanaceti haplotypes were closely related, and clustered in the Didymella sensu stricto clade. Based on these phylogenetic results, supported by their distinct morphology and cultural characteristics, the two haplotypes of M. tanaceti are reclassified as two species of Didymella, namely D. rosea and D. tanaceti. The implications of two closely related species causing tan spot of pyrethrum are discussed.
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    Fungal Planet description sheets: 400-468
    Crous, PW ; Wingfield, MJ ; Richardson, DM ; Le Roux, JJ ; Strasberg, D ; Edwards, J ; Roets, F ; Hubka, V ; Taylor, PWJ ; Heykoop, M ; Martin, MP ; Moreno, G ; Sutton, DA ; Wiederhold, NP ; Barnes, CW ; Carlavilla, JR ; Gene, J ; Giraldo, A ; Guarnaccia, V ; Guarro, J ; Hernandez-Restrepo, M ; Kolarik, M ; Manjon, JL ; Pascoe, IG ; Popov, ES ; Sandoval-Denis, M ; Woudenberg, JHC ; Acharya, K ; Alexandrova, AV ; Alvarado, P ; Barbosa, RN ; Baseia, IG ; Blanchette, RA ; Boekhout, T ; Burgess, TI ; Cano-Lira, JF ; Cmokova, A ; Dimitrov, RA ; Dyakov, MY ; Duenas, M ; Dutta, AK ; Esteve-Raventos, F ; Fedosova, AG ; Fournier, J ; Gamboa, P ; Gouliamova, DE ; Grebenc, T ; Groenewald, M ; Hanse, B ; Hardy, GESJ ; Held, BW ; Jurjevic, Z ; Kaewgrajang, T ; Latha, KPD ; Lombard, L ; Luangsa-ard, JJ ; Lyskova, P ; Mallatova, N ; Manimohan, P ; Miller, AN ; Mirabolfathy, M ; Morozova, OV ; Obodai, M ; Oliveira, NT ; Ordonez, ME ; Otto, EC ; Paloi, S ; Peterson, SW ; Phosri, C ; Roux, J ; Salazar, WA ; Sanchez, A ; Sarria, GA ; Shin, H-D ; Silva, BDB ; Silva, GA ; Smith, MT ; Souza-Motta, CM ; Stchigel, AM ; Stoilova-Disheva, MM ; Sulzbacher, MA ; Telleria, MT ; Toapanta, C ; Traba, JM ; Valenzuela-Lopez, N ; Watling, R ; Groenewald, JZ (RIJKSHERBARIUM, 2016-06)
    Novel species of fungi described in the present study include the following from Australia: Vermiculariopsiella eucalypti, Mulderomyces natalis (incl. Mulderomyces gen. nov.), Fusicladium paraamoenum, Neotrimmatostroma paraexcentricum, and Pseudophloeospora eucalyptorum on leaves of Eucalyptus spp., Anungitea grevilleae (on leaves of Grevillea sp.), Pyrenochaeta acaciae (on leaves of Acacia sp.), and Brunneocarpos banksiae (incl. Brunneocarpos gen. nov.) on cones of Banksia attenuata. Novel foliicolous taxa from South Africa include Neosulcatispora strelitziae (on Strelitzia nicolai), Colletotrichum ledebouriae (on Ledebouria floridunda), Cylindrosympodioides brabejum (incl. Cylindrosympodioides gen. nov.) on Brabejum stellatifolium, Sclerostagonospora ericae (on Erica sp.), Setophoma cyperi (on Cyperus sphaerocephala), and Phaeosphaeria breonadiae (on Breonadia microcephala). Novelties described from Robben Island (South Africa) include Wojnowiciella cissampeli and Diaporthe cissampeli (both on Cissampelos capensis), Phaeotheca salicorniae (on Salicornia meyeriana), Paracylindrocarpon aloicola (incl. Paracylindrocarpon gen. nov.) on Aloe sp., and Libertasomyces myopori (incl. Libertasomyces gen. nov.) on Myoporum serratum. Several novelties are recorded from La Réunion (France), namely Phaeosphaeriopsis agapanthi (on Agapanthus sp.), Roussoella solani (on Solanum mauritianum), Vermiculariopsiella acaciae (on Acacia heterophylla), Dothiorella acacicola (on Acacia mearnsii), Chalara clidemiae (on Clidemia hirta), Cytospora tibouchinae (on Tibouchina semidecandra), Diaporthe ocoteae (on Ocotea obtusata), Castanediella eucalypticola, Phaeophleospora eucalypticola and Fusicladium eucalypticola (on Eucalyptus robusta), Lareunionomyces syzygii (incl. Lareunionomyces gen. nov.) and Parawiesneriomyces syzygii (incl. Parawiesneriomyces gen. nov.) on leaves of Syzygium jambos. Novel taxa from the USA include Meristemomyces arctostaphylos (on Arctostaphylos patula), Ochroconis dracaenae (on Dracaena reflexa), Rasamsonia columbiensis (air of a hotel conference room), Paecilomyces tabacinus (on Nicotiana tabacum), Toxicocladosporium hominis (from human broncoalveolar lavage fluid), Nothophoma macrospora (from respiratory secretion of a patient with pneumonia), and Penidiellopsis radicularis (incl. Penidiellopsis gen. nov.) from a human nail. Novel taxa described from Malaysia include Prosopidicola albizziae (on Albizzia falcataria), Proxipyricularia asari (on Asarum sp.), Diaporthe passifloricola (on Passiflora foetida), Paramycoleptodiscus albizziae (incl. Paramycoleptodiscus gen. nov.) on Albizzia falcataria, and Malaysiasca phaii (incl. Malaysiasca gen. nov.) on Phaius reflexipetalus. Two species are newly described from human patients in the Czech Republic, namely Microascus longicollis (from toenails of patient with suspected onychomycosis), and Chrysosporium echinulatum (from sole skin of patient). Furthermore, Alternaria quercicola is described on leaves of Quercus brantii (Iran), Stemphylium beticola on leaves of Beta vulgaris (The Netherlands), Scleroderma capeverdeanum on soil (Cape Verde Islands), Scleroderma dunensis on soil, and Blastobotrys meliponae from bee honey (Brazil), Ganoderma mbrekobenum on angiosperms (Ghana), Geoglossum raitviirii and Entoloma kruticianum on soil (Russia), Priceomyces vitoshaensis on Pterostichus melas (Carabidae) (Bulgaria) is the only one for which the family is listed, Ganoderma ecuadoriense on decaying wood (Ecuador), Thyrostroma cornicola on Cornus officinalis (Korea), Cercophora vinosa on decorticated branch of Salix sp. (France), Coprinus pinetorum, Coprinus littoralis and Xerocomellus poederi on soil (Spain). Two new genera from Colombia include Helminthosporiella and Uwemyces on leaves of Elaeis oleifera. Two species are described from India, namely Russula intervenosa (ectomycorrhizal with Shorea robusta), and Crinipellis odorata (on bark of Mytragyna parviflora). Novelties from Thailand include Cyphellophora gamsii (on leaf litter), Pisolithus aureosericeus and Corynascus citrinus (on soil). Two species are newly described from Citrus in Italy, namely Dendryphiella paravinosa on Citrus sinensis, and Ramularia citricola on Citrus floridana. Morphological and culture characteristics along with ITS nrDNA barcodes are provided for all taxa.
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    Take-all or nothing
    Hernandez-Restrepo, M ; Groenewald, JZ ; Elliott, ML ; Canning, G ; McMillan, VE ; Crous, PW (CENTRAALBUREAU SCHIMMELCULTURE, 2016-03)
    Take-all disease of Poaceae is caused by Gaeumannomyces graminis (Magnaporthaceae). Four varieties are recognised in G. graminis based on ascospore size, hyphopodial morphology and host preference. The aim of the present study was to clarify boundaries among species and varieties in Gaeumannomyces by combining morphology and multi-locus phylogenetic analyses based on partial gene sequences of ITS, LSU, tef1 and rpb1. Two new genera, Falciphoriella and Gaeumannomycella were subsequently introduced in Magnaporthaceae. The resulting phylogeny revealed several cryptic species previously overlooked within Gaeumannomyces. Isolates of Gaeumannomyces were distributed in four main clades, from which 19 species could be delimited, 12 of which were new to science. Our results show that the former varieties Gaeumannomyces graminis var. avenae and Gaeumannomyces graminis var. tritici represent species phylogenetically distinct from G. graminis, for which the new combinations G. avenae and G. tritici are introduced. Based on molecular data, morphology and host preferences, Gaeumannomyces graminis var. maydis is proposed as a synonym of G. radicicola. Furthermore, an epitype for Gaeumannomyces graminis var. avenae was designated to help stabilise the application of that name.
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    Taxonomic and phylogenetic re-evaluation of Microdochium, Monographella and Idriella
    Hernandez-Restrepo, M ; Groenewald, JZ ; Crous, PW (RIJKSHERBARIUM, 2016-06)
    Based on morphology and DNA sequence data the taxonomic relationships of Microdochium, Monographella and Idriella were reassessed. Microdochium is morphologically and phylogenetically circumscribed, and the sexual genus Monographella treated as synonym on the basis that Microdochium has more species, is more commonly encountered, and more frequently used in literature. An epitype is designated for Microdochium phragmites, and several well-known species are redefined based on their morphology and DNA sequence data (LSU, ITS, BTUB and RPB2). Furthermore, the revision of Microdochium led to six new combinations (M. albescens, M. consociatum, M. fusariisporum, M. maydis, M. opuntiae and M. stevensonii) and six new species (M. citrinidiscum, M. colombiense, M. fisheri, M. neoqueenslandicum, M. seminicola and M. trichocladiopsis) being proposed. Microdochium s.str. belongs to a monophyletic clade, together with Idriella lunata and Selenodriella, representing a new family, Microdochiaceae, in Xylariales. Other species previously accommodated in Microdochium belong to different orders in the Ascomycota. Microdochium gracile belongs to Sordariomycetes (incertae sedis) and Paramicrodochium is proposed to accommodate this species. Microdochium tripsaci belongs to Ephelis in Clavicipitaceae, while M. fusarioides belongs to a new genus, Microdochiella in Orbiliales. Idriella s.str. is a monotypic genus phylogenetically closely related to Microdochium. Idriella s.l. separates into different genera in Xylariales (incertae sedis) including Castanediella, Selenodriella, Idriellopsis, Neoidriella and Paraidriella, the last three proposed here as new genera.
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    Fungal Planet description sheets: 469-557
    Crous, PW ; Wingfiel, MJ ; Burgess, TI ; Hardy, GESJ ; Crane, C ; Barrett, S ; Cano-Lira, JF ; Le Roux, JJ ; Thangavel, R ; Guarro, J ; Stchigel, AM ; Martin, MP ; Alfredo, DS ; Barber, PA ; Barreto, RW ; Baseia, IG ; Cano-Canals, J ; Cheewangkoon, R ; Ferreira, RJ ; Gene, J ; Lechat, C ; Moreno, G ; Roets, F ; Shivas, RG ; Sousa, JO ; Tan, YP ; Wiederhold, NP ; Abell, SE ; Accioly, T ; Albizu, JL ; Alves, JL ; Antoniolli, ZI ; Aplin, N ; Araujo, J ; Arzanlou, M ; Bezerra, JDP ; Bouchara, J-P ; Carlavilla, JR ; Castillo, A ; Castroagudin, VL ; Ceresini, PC ; Claridge, GF ; Coelho, G ; Coimbra, VRM ; Costa, LA ; da Cunha, KC ; da Silva, SS ; Daniel, R ; de Beer, ZW ; Duenas, M ; Edwards, J ; Enwistle, P ; Fiuza, PO ; Fournier, J ; Garcia, D ; Gibertoni, TB ; Giraud, S ; Guevara-Suarez, M ; Gusmao, LFP ; Haituk, S ; Heykoop, M ; Hirooka, Y ; Hofmann, TA ; Houbraken, J ; Hughes, DP ; Kautmanova, I ; Koppel, O ; Koukol, O ; Larsson, E ; Latha, KPD ; Lee, DH ; Lisboa, DO ; Lisboa, WS ; Lopez-Villalba, A ; Maciel, JLN ; Manimohan, P ; Manjon, JL ; Marincowitz, S ; Marney, TS ; Meijer, M ; Miller, AN ; Olariaga, I ; Paiva, LM ; Piepenbring, M ; Poveda-Molero, JC ; Raj, KNA ; Raja, HA ; Rougeron, A ; Salcedo, I ; Samadi, R ; Santos, TAB ; Scarlett, K ; Seifert, KA ; Shuttleworth, LA ; Silva, GA ; Silva, M ; Siqueira, JPZ ; Souza-Motta, CM ; Stephenson, SL ; Sutton, DA ; Tamakeaw, N ; Telleria, MT ; Valenzuela-Lopez, N ; Viljoen, A ; Visagie, CM ; Vizzini, A ; Wartchow, F ; Wingfield, BD ; Yurchenko, E ; Zamora, JC ; Groenewald, JZ (RIJKSHERBARIUM, 2016-12)
    Novel species of fungi described in this study include those from various countries as follows: Australia: Apiognomonia lasiopetali on Lasiopetalum sp., Blastacervulus eucalyptorum on Eucalyptus adesmophloia, Bullanockia australis (incl. Bullanockia gen. nov.) on Kingia australis, Caliciopsis eucalypti on Eucalyptus marginata, Celerioriella petrophiles on Petrophile teretifolia, Coleophoma xanthosiae on Xanthosia rotundifolia, Coniothyrium hakeae on Hakea sp., Diatrypella banksiae on Banksia formosa, Disculoides corymbiae on Corymbia calophylla, Elsinoë eelemani on Melaleuca alternifolia, Elsinoë eucalyptigena on Eucalyptus kingsmillii, Elsinoë preissianae on Eucalyptus preissiana, Eucasphaeria rustici on Eucalyptus creta, Hyweljonesia queenslandica (incl. Hyweljonesia gen. nov.) on the cocoon of an unidentified microlepidoptera, Mycodiella eucalypti (incl. Mycodiella gen. nov.) on Eucalyptus diversicolor, Myrtapenidiella sporadicae on Eucalyptus sporadica, Neocrinula xanthorrhoeae (incl. Neocrinula gen. nov.) on Xanthorrhoea sp., Ophiocordyceps nooreniae on dead ant, Phaeosphaeriopsis agavacearum on Agave sp., Phlogicylindrium mokarei on Eucalyptus sp., Phyllosticta acaciigena on Acacia suaveolens, Pleurophoma acaciae on Acacia glaucoptera, Pyrenochaeta hakeae on Hakea sp., Readeriella lehmannii on Eucalyptus lehmannii, Saccharata banksiae on Banksia grandis, Saccharata daviesiae on Daviesia pachyphylla, Saccharata eucalyptorum on Eucalyptus bigalerita, Saccharata hakeae on Hakea baxteri, Saccharata hakeicola on Hakea victoria, Saccharata lambertiae on Lambertia ericifolia, Saccharata petrophiles on Petrophile sp., Saccharata petrophilicola on Petrophile fastigiata, Sphaerellopsis hakeae on Hakea sp., and Teichospora kingiae on Kingia australis.Brazil: Adautomilanezia caesalpiniae (incl. Adautomilanezia gen. nov.) on Caesalpina echinata, Arthrophiala arthrospora (incl. Arthrophiala gen. nov.) on Sagittaria montevidensis, Diaporthe caatingaensis (endophyte from Tacinga inamoena), Geastrum ishikawae on sandy soil, Geastrum pusillipilosum on soil, Gymnopus pygmaeus on dead leaves and sticks, Inonotus hymenonitens on decayed angiosperm trunk, Pyricularia urashimae on Urochloa brizantha, and Synnemellisia aurantia on Passiflora edulis. Chile: Tubulicrinis australis on Lophosoria quadripinnata.France: Cercophora squamulosa from submerged wood, and Scedosporium cereisporum from fluids of a wastewater treatment plant. Hawaii: Beltraniella acaciae, Dactylaria acaciae, Rhexodenticula acaciae, Rubikia evansii and Torula acaciae (all on Acacia koa).India: Lepidoderma echinosporum on dead semi-woody stems, and Rhodocybe rubrobrunnea from soil. Iran: Talaromyces kabodanensis from hypersaline soil. La Réunion: Neocordana musarum from leaves of Musa sp. Malaysia: Anungitea eucalyptigena on Eucalyptus grandis × pellita, Camptomeriphila leucaenae (incl. Camptomeriphila gen. nov.) on Leucaena leucocephala, Castanediella communis on Eucalyptus pellita, Eucalyptostroma eucalypti (incl. Eucalyptostroma gen. nov.) on Eucalyptus pellita, Melanconiella syzygii on Syzygium sp., Mycophilomyces periconiae (incl. Mycophilomyces gen. nov.) as hyperparasite on Periconia on leaves of Albizia falcataria, Synnemadiella eucalypti (incl. Synnemadiella gen. nov.) on Eucalyptus pellita, and Teichospora nephelii on Nephelium lappaceum.Mexico: Aspergillus bicephalus from soil. New Zealand: Aplosporella sophorae on Sophora microphylla, Libertasomyces platani on Platanus sp., Neothyronectria sophorae (incl. Neothyronectria gen. nov.) on Sophora microphylla, Parastagonospora phoenicicola on Phoenix canariensis, Phaeoacremonium pseudopanacis on Pseudopanax crassifolius, Phlyctema phoenicis on Phoenix canariensis, and Pseudoascochyta novae-zelandiae on Cordyline australis.Panama: Chalara panamensis from needle litter of Pinus cf. caribaea. South Africa: Exophiala eucalypti on leaves of Eucalyptus sp., Fantasmomyces hyalinus (incl. Fantasmomyces gen. nov.) on Acacia exuvialis, Paracladophialophora carceris (incl. Paracladophialophora gen. nov.) on Aloe sp., and Umthunziomyces hagahagensis (incl. Umthunziomyces gen. nov.) on Mimusops caffra.Spain: Clavaria griseobrunnea on bare ground in Pteridium aquilinum field, Cyathus ibericus on small fallen branches of Pinus halepensis, Gyroporus pseudolacteus in humus of Pinus pinaster, and Pseudoascochyta pratensis (incl. Pseudoascochyta gen. nov.) from soil. Thailand: Neoascochyta adenii on Adenium obesum, and Ochroconis capsici on Capsicum annuum. UK: Fusicolla melogrammae from dead stromata of Melogramma campylosporum on bark of Carpinus betulus. Uruguay: Myrmecridium pulvericola from house dust. USA: Neoscolecobasidium agapanthi (incl. Neoscolecobasidium gen. nov.) on Agapanthus sp., Polyscytalum purgamentum on leaf litter, Pseudopithomyces diversisporus from human toenail, Saksenaea trapezispora from knee wound of a soldier, and Sirococcus quercus from Quercus sp. Morphological and culture characteristics along with DNA barcodes are provided.
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    Pyricularia graminis-tritici, a new Pyricularia species causing wheat blast
    Castroagudin, VL ; Moreira, SI ; Pereira, DAS ; Moreira, SS ; Brunner, PC ; Maciel, JLN ; Crous, PW ; McDonald, BA ; Alves, E ; Ceresini, PC (RIJKSHERBARIUM, 2016-12)
    Pyricularia oryzae is a species complex that causes blast disease on more than 50 species of poaceous plants. Pyricularia oryzae has a worldwide distribution as a rice pathogen and in the last 30 years emerged as an important wheat pathogen in southern Brazil. We conducted phylogenetic analyses using 10 housekeeping loci for 128 isolates of P. oryzae sampled from sympatric populations of wheat, rice, and grasses growing in or near wheat fields. Phylogenetic analyses grouped the isolates into three major clades. Clade 1 comprised isolates associated only with rice and corresponds to the previously described rice blast pathogen P. oryzae pathotype Oryza (PoO). Clade 2 comprised isolates associated almost exclusively with wheat and corresponds to the previously described wheat blast pathogen P. oryzae pathotype Triticum (PoT). Clade 3 contained isolates obtained from wheat as well as other Poaceae hosts. We found that Clade 3 is distinct from P. oryzae and represents a new species, Pyricularia graminis-tritici (Pgt). No morphological differences were observed among these species, but a distinctive pathogenicity spectrum was observed. Pgt and PoT were pathogenic and highly aggressive on Triticum aestivum (wheat), Hordeum vulgare (barley), Urochloa brizantha (signal grass), and Avena sativa (oats). PoO was highly virulent on the original rice host (Oryza sativa), and also on wheat, barley, and oats, but not on signal grass. We conclude that blast disease on wheat and its associated Poaceae hosts in Brazil is caused by multiple Pyricularia species. Pyricularia graminis-tritici was recently found causing wheat blast in Bangladesh. This indicates that P. graminis-tritici represents a serious threat to wheat cultivation globally.
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    All that glitters is not Ramularia
    Videira, SIR ; Groenewald, JZ ; Braun, U ; Shin, HD ; Crous, PW (CENTRAALBUREAU SCHIMMELCULTURE, 2016-03)
    Ramularia is a species-rich genus that harbours plant pathogens responsible for yield losses to many important crops, including barley, sugar beet and strawberry. Species of Ramularia are hyphomycetes with hyaline conidiophores and conidia with distinct, thickened, darkened, refractive conidiogenous loci and conidial hila, and Mycosphaerella sexual morphs. Because of its simple morphology and general lack of DNA data in public databases, several allied genera are frequently confused with Ramularia. In order to improve the delimitation of Ramularia from allied genera and the circumscription of species within the genus Ramularia, a polyphasic approach based on multilocus DNA sequences, morphological and cultural data were used in this study. A total of 420 isolates belonging to Ramularia and allied genera were targeted for the amplification and sequencing of six partial genes. Although Ramularia and Ramulariopsis proved to be monophyletic, Cercosporella and Pseudocercosporella were polyphyletic. Phacellium isolates clustered within the Ramularia clade and the genus is thus tentatively reduced to synonymy under Ramularia. Cercosporella and Pseudocercosporella isolates that were not congeneric with the ex-type strains of the type species of those genera were assigned to existing genera or to the newly introduced genera Teratoramularia and Xenoramularia, respectively. Teratoramularia is a genus with ramularia-like morphology belonging to the Teratosphaeriaceae, and Xenoramularia was introduced to accommodate hyphomycetous species closely related to Zymoseptoria. The genera Apseudocercosporella, Epicoleosporium, Filiella, Fusidiella, Neopseudocercosporella, and Mycosphaerelloides were also newly introduced to accommodate species non-congeneric with their purported types. A total of nine new combinations and 24 new species were introduced in this study.