Jolanda Roux
University of Pretoria
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Mycological Progress | 2010
B. A. Didier Begoude; Bernard Slippers; Michael J. Wingfield; Jolanda Roux
Species in the Botryosphaeriaceae represent some of the most important fungal pathogens of woody plants. Although these fungi have been relatively well studied on economically important crops, hardly anything is known regarding their taxonomy or ecology on native or non-commercial tree species. The aim of this study was to compare the diversity and distribution of the Botryosphaeriaceae on Terminalia catappa, a tropical tree of Asian origin planted as an ornamental in Cameroon, Madagascar and South Africa. A total of 83 trees were sampled, yielding 79 Botryosphaeriaceae isolates. Isolates were initially grouped based on morphology of cultures and conidia. Representatives of the different morphological groups were then further characterised using sequence data for the ITS, tef 1-alpha, rpb2, BOTF15 and beta-tub gene regions. Five species of the Botryosphaeriaceae were identified, including Neofusicoccum parvum, N. batangarum sp. nov., Lasiodiplodia pseudotheobromae, L. theobromae and L. mahajangana sp. nov. Lasiodiplodia pseudotheobromae and L. theobromae, were the most commonly isolated species (62%), and were found at all the sites. Neofusicoccum parvum and N. batangarum were found in South Africa and Cameroon, respectively, whereas L. mahajangana was found only in Madagascar. Greenhouse inoculation trials performed on young T. catappa trees showed variation among isolates tested, with L. pseudotheobromae being the most pathogenic. The Botryosphaeriaceae infecting T. catappa appear to be dominated by generalist species that also occur on various other hosts in tropical and sub-tropical climates.
Persoonia | 2013
Pedro W. Crous; Michael J. Wingfield; Josep Guarro; Ratchadawan Cheewangkoon; M. Van der Bank; Wijnand J. Swart; Alberto M. Stchigel; José F. Cano-Lira; Jolanda Roux; H. Madrid; Ulrike Damm; Alan R. Wood; Lucas A. Shuttleworth; C.S. Hodges; M. Munster; M. de Jesús Yáñez-Morales; L. Zúñiga-Estrada; Elsie M. Cruywagen; G.S. de Hoog; C. Silvera; J. Najafzadeh; E.M. Davison; P.J.N. Davison; M.D. Barrett; R.L. Barrett; Dimuthu S. Manamgoda; Andrew M. Minnis; N.M. Kleczewski; S.L. Flory; Lisa A. Castlebury
Novel species of microfungi described in the present study include the following from South Africa: Camarosporium aloes, Phaeococcomyces aloes and Phoma aloes from Aloe, C. psoraleae, Diaporthe psoraleae and D. psoraleae-pinnatae from Psoralea, Colletotrichum euphorbiae from Euphorbia, Coniothyrium prosopidis and Peyronellaea prosopidis from Prosopis, Diaporthe cassines from Cassine, D. diospyricola from Diospyros, Diaporthe maytenicola from Maytenus, Harknessia proteae from Protea, Neofusicoccum ursorum and N. cryptoaustrale from Eucalyptus, Ochrocladosporium adansoniae from Adansonia, Pilidium pseudoconcavum from Greyia radlkoferi, Stagonospora pseudopaludosa from Phragmites and Toxicocladosporium ficiniae from Ficinia. Several species were also described from Thailand, namely: Chaetopsina pini and C. pinicola from Pinus spp., Myrmecridium thailandicum from reed litter, Passalora pseudotithoniae from Tithonia, Pallidocercospora ventilago from Ventilago, Pyricularia bothriochloae from Bothriochloa and Sphaerulina rhododendricola from Rhododendron. Novelties from Spain include Cladophialophora multiseptata, Knufia tsunedae and Pleuroascus rectipilus from soil and Cyphellophora catalaunica from river sediments. Species from the USA include Bipolaris drechsleri from Microstegium, Calonectria blephiliae from Blephilia, Kellermania macrospora (epitype) and K. pseudoyuccigena from Yucca. Three new species are described from Mexico, namely Neophaeosphaeria agaves and K. agaves from Agave and Phytophthora ipomoeae from Ipomoea. Other African species include Calonectria mossambicensis from Eucalyptus (Mozambique), Harzia cameroonensis from an unknown creeper (Cameroon), Mastigosporella anisophylleae from Anisophyllea (Zambia) and Teratosphaeria terminaliae from Terminalia (Zimbabwe). Species from Europe include Auxarthron longisporum from forest soil (Portugal), Discosia pseudoartocreas from Tilia (Austria), Paraconiothyrium polonense and P. lycopodinum from Lycopodium (Poland) and Stachybotrys oleronensis from Iris (France). Two species of Chrysosporium are described from Antarctica, namely C. magnasporum and C. oceanitesii. Finally, Licea xanthospora is described from Australia, Hypochnicium huinayensis from Chile and Custingophora blanchettei from Uruguay. Novel genera of Ascomycetes include Neomycosphaerella from Pseudopentameris macrantha (South Africa), and Paramycosphaerella from Brachystegia sp. (Zimbabwe). Novel hyphomycete genera include Pseudocatenomycopsis from Rothmannia (Zambia), Neopseudocercospora from Terminalia (Zambia) and Neodeightoniella from Phragmites (South Africa), while Dimorphiopsis from Brachystegia (Zambia) represents a novel coelomycetous genus. Furthermore, Alanphillipsia is introduced as a new genus in the Botryosphaeriaceae with four species, A. aloes, A. aloeigena and A. aloetica from Aloe spp. and A. euphorbiae from Euphorbia sp. (South Africa). A new combination is also proposed for Brachysporium torulosum (Deightoniella black tip of banana) as Corynespora torulosa. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.
Forest Ecology and Management | 1997
Jolanda Roux; Michael J. Wingfield
Abstract Various disease symptoms occur on Acacia mearnsii in South Africa, of which black butt, on older trees, is the most common. Other less commonly reported symptoms include gummosis, cracks, discoloured lesions and die-back. These diseases are of unknown aetiology. During a 2-year period, a survey of diseases on A. mearnsii was conducted in two major commercial wattle-growing areas of South Africa. Samples were collected from all symptomatic tissue on randomly selected trees in each area. A wide range of fungi were isolated, including species of Phytophthora, Seiridium, Sphaeropsis, Fusarium, Diplodia, Ceratocystis and Botryosphaeria. Of these, Phytophthora spp. were isolated only from basal lesions and soil, whereas the Diplodia and Fusarium spp. were the most frequently isolated from diseased tissue on aboveground parts of trees. Phytophthora parasitica and Ceratocystis albofundus, which are well-known pathogens of A. mearnsii, were excluded from the pathogenicity tests. All other fungi isolated, and particularly those belonging to genera that are known plant pathogens, were used in pathogenicity tests to determine their possible role in diseases. For each isolate, 20 saplings were inoculated in the field, and the resultant lesion lengths were measured. Only the Phytophthora spp., Botryosphaeria sp. and Sphaeropsis sp. produced noticeable lesions. From the surveys and pathogenicity tests, it is clear that many fungi are associated with diseases of A. mearnsii, and that these deserve further study.
Persoonia | 2014
Pedro W. Crous; Roger G. Shivas; W. Quaedvlieg; M. Van der Bank; Y. Zhang; Brett A. Summerell; Josep Guarro; Michael J. Wingfield; Alan R. Wood; Acelino Couto Alfenas; Uwe Braun; J. F. Cano-Lira; Dania García; Yasmina Marin-Felix; P. Alvarado; J.P. Andrade; J. Armengol; A. Assefa; A. den Breeÿen; Ippolito Camele; Ratchadawan Cheewangkoon; J.T. De Souza; Tuan A. Duong; F. Esteve-Raventós; Jacques Fournier; Salvatore Frisullo; J. García-Jiménez; A. Gardiennet; Josepa Gené; Margarita Hernández-Restrepo
Novel species of microfungi described in the present study include the following from South Africa: Cercosporella dolichandrae from Dolichandra unguiscati, Seiridium podocarpi from Podocarpus latifolius, Pseudocercospora parapseudarthriae from Pseudarthria hookeri, Neodevriesia coryneliae from Corynelia uberata on leaves of Afrocarpus falcatus, Ramichloridium eucleae from Euclea undulata and Stachybotrys aloeticola from Aloe sp. (South Africa), as novel member of the Stachybotriaceae fam. nov. Several species were also described from Zambia, and these include Chaetomella zambiensis on unknown Fabaceae, Schizoparme pseudogranati from Terminalia stuhlmannii, Diaporthe isoberliniae from Isoberlinia angolensis, Peyronellaea combreti from Combretum mossambiciensis, Zasmidium rothmanniae and Phaeococcomyces rothmanniae from Rothmannia engleriana, Diaporthe vangueriae from Vangueria infausta and Diaporthe parapterocarpi from Pterocarpus brenanii. Novel species from the Netherlands include: Stagonospora trichophoricola, Keissleriella trichophoricola and Dinemasporium trichophoricola from Trichophorum cespitosum, Phaeosphaeria poae, Keissleriella poagena, Phaeosphaeria poagena, Parastagonospora poagena and Pyrenochaetopsis poae from Poa sp., Septoriella oudemansii from Phragmites australis and Dendryphion europaeum from Hedera helix (Germany) and Heracleum sphondylium (the Netherlands). Novel species from Australia include: Anungitea eucalyptorum from Eucalyptus leaf litter, Beltraniopsis neolitseae and Acrodontium neolitseae from Neolitsea australiensis, Beltraniella endiandrae from Endiandra introrsa, Phaeophleospora parsoniae from Parsonia straminea, Penicillifer martinii from Cynodon dactylon, Ochroconis macrozamiae from Macrozamia leaf litter, Triposporium cycadicola, Circinotrichum cycadis, Cladosporium cycadicola and Acrocalymma cycadis from Cycas spp. Furthermore, Vermiculariopsiella dichapetali is described from Dichapetalum rhodesicum (Botswana), Ophiognomonia acadiensis from Picea rubens (Canada), Setophoma vernoniae from Vernonia polyanthes and Penicillium restingae from soil (Brazil), Pseudolachnella guaviyunis from Myrcianthes pungens (Uruguay) and Pseudocercospora neriicola from Nerium oleander (Italy). Novelties from Spain include: Dendryphiella eucalyptorum from Eucalyptus globulus, Conioscypha minutispora from dead wood, Diplogelasinospora moalensis and Pseudoneurospora canariensis from soil and Inocybe lanatopurpurea from reforested woodland of Pinus spp. Novelties from France include: Kellermania triseptata from Agave angustifolia, Zetiasplozna acaciae from Acacia melanoxylon, Pyrenochaeta pinicola from Pinus sp. and Pseudonectria rusci from Ruscus aculeatus. New species from China include: Dematiocladium celtidicola from Celtis bungeana, Beltrania pseudorhombica, Chaetopsina beijingensis and Toxicocladosporium pini from Pinus spp. and Setophaeosphaeria badalingensis from Hemerocallis fulva. Novel genera of Ascomycetes include Alfaria from Cyperus esculentus (Spain), Rinaldiella from a contaminated human lesion (Georgia), Hyalocladosporiella from Tectona grandis (Brazil), Pseudoacremonium from Saccharum spontaneum and Melnikomyces from leaf litter (Vietnam), Annellosympodiella from Juniperus procera (Ethiopia), Neoceratosperma from Eucalyptus leaves (Thailand), Ramopenidiella from Cycas calcicola (Australia), Cephalotrichiella from air in the Netherlands, Neocamarosporium from Mesembryanthemum sp. and Acervuloseptoria from Ziziphus mucronata (South Africa) and Setophaeosphaeria from Hemerocallis fulva (China). Several novel combinations are also introduced, namely for Phaeosphaeria setosa as Setophaeosphaeria setosa, Phoma heteroderae as Peyronellaea heteroderae and Phyllosticta maydis as Peyronellaea maydis. Morphological and culture characteristics along with ITS DNA barcodes are provided for all taxa.
Mycologia | 2003
Irene Barnes; Jolanda Roux; Brenda D. Wingfield; M. J. Dudzinski; K. M. Old; Michael J. Wingfield
Several species of Ceratocystis have been recorded on Eucalyptus. These include C. fimbriata, C. eucalypti, C. moniliformis and C. moniliformopsis. Of these, only C. fimbriata is known as a pathogen; it recently has been found causing serious wilt diseases in Uganda, Congo and Brazil. This study was undertaken to collect Ceratocystis species, including C. eucalypti, from artificially induced wounds on Eucalyptus nitens near Canberra in southeastern Australia. Trees were wounded in October 2000, and wounds were examined approximately one month later. Ascomata characteristic of a Ceratocystis species were found covering the wounds, and this fungus also was isolated from the wood using carrot baiting. This species of Ceratocystis has hat-shaped ascospores similar to those of C. fimbriata, but it differs from C. fimbriata and all other species of Ceratocystis in that it possesses ascomata with a pyriform base. Comparison of DNA sequences from the ITS and 5.8S rRNA operon confirmed that the fungus from E. nitens in Australia is unique, and we describe it here as a new species, C. pirilliformis.
IMA Fungus | 2013
Jolanda Roux; Izette Greyling; T. A. Coutinho; Marcel Verleur; M.J. Wingfield
Puccinia psidii, the cause of a disease today commonly referred to as Myrtle rust, is considered a high priority quarantine threat globally. It has a wide host range in the Myrtaceae and it is feared that it may result in significant damage to native ecosystems where these plants occur. The fungus is also of considerable concern to plantation forestry industries that propagate Australian Eucalyptus species. In May 2013, symptoms of a rust disease resembling those of P. psidii were observed on an ornamental Myrtaceous shrub in a garden in South Africa. The fungus was identified based on DNA sequence data of the ITS and 5.8S nrRNA gene regions and here we report, for the first time, the presence of P. psidii in Africa.
Fungal Biology | 2004
Gavin C. Hunter; Jolanda Roux; Brenda D. Wingfield; Pedro W. Crous; Michael J. Wingfield
Commercial Eucalyptus plantations provide an important source of hardwood for forestry industries, worldwide. Several species of Mycosphaerella are associated with a destructive Eucalyptus leaf disease known as Mycosphaerella Leaf Blotch (MLB). During 2000, a survey was undertaken in several commercial Eucalyptus growing areas of South Africa to determine the identity of the Mycosphaerella spp. contributing to outbreaks of MLB. Symptomatic leaf samples were collected from three major Eucalyptus growing areas and the Mycosphaerella spp. were isolated. Isolates were identified using morphology, ascospore germination patterns and sequence data from the ribosomal DNA operon. Six species, namely M. ellipsoidea, M. irregulariramosa, M. juvenis, M. lateralis, M. marksii, M. nubilosa, as well as a new species, described here as M. fori sp. nov., were recognized. Mycosphaerella nubilosa was the most common species isolated from commercial plantations, particularly on E. nitens, and appears to be the dominant species contributing to MLB. Data obtained in this study show that MLB is caused by a complex of species contributing to disease outbreaks in South Africa.
Plant Disease | 2001
Irene Barnes; Jolanda Roux; Michael J. Wingfield; Martin Petrus Albertus Coetzee; Brenda D. Wingfield
Cypress canker is a serious disease that has devastated Cupressus spp. in many parts of the world. In Mediterranean Europe it has caused the deaths of millions of trees. Three species of Seiridium, S. cardinale, S. cupressi, and S. unicorne, are associated with cypress canker. Considerable debate surrounds the taxonomic status of these fungi. They have been viewed as a single morphologically variable species, three distinct taxa; or two species based on the presence or absence of conidial appendages. Studies based on ribosomal DNA (ITS1, ITS2, and 5.8S gene) sequence failed to separate the cypress canker fungi. In an attempt to distinguish between the species associated with cypress canker we used histone and partial ß-tubulin sequences of fourteen isolates of Seiridium spp. from cypress. Analysis of sequence data showed Seiridium isolates from Cupressus spp., residing in two major clades. One clade accommodated S. unicorne isolates from Portugal and South Africa. The other major clade consisted of two subclades containing non-appendaged S. cardinale isolates. We believe the larger second clade, represents the cypress canker pathogens while the other clade contains the less pathogenic S. unicorne, which has a host range beyond Cupressus. This study thus provides strong evidence to support previous morphological data suggesting three distinct species are associated with cypress canker.
Southern Forests | 2009
Jolanda Roux; Michael J. Wingfield
The fungal genus Ceratocystis includes many economically important tree pathogens. Until the 1980s, this genus of plant pathogens was not known from non-native plantation-grown forestry species. However, during the course of the last 20 years, a number of reports have been made of Ceratocystis spp. causing death of non-native plantation-grown forestry species from several locations worldwide. Affected trees include both Australian Acacia spp. and Eucalyptus spp. The first report of disease caused by a Ceratocystis sp. on Eucalyptus was made less than 10 years ago from Central Africa and, shortly thereafter, the disease was reported from Brazil. Subsequently, a number of other reports of Ceratocystis diseases have emerged from Africa, South America and Asia. These diseases are characterised by rapid wilt and death of trees and they have been reported to affect coppice stems as well as mature trees. In many cases, infection is associated with pruning wounds or other mechanical damage. The causal agent has been reported as Ceratocystis fimbriata s.l., but the Eucalyptus pathogen most likely represents a number of previously undescribed species. Ceratocystis spp. are vectored by wood- and bark-associated insects and typically those that visit fresh wounds, which act as infection courts. The fungi infect woody tissue and produce fruity aromas, which are attractive to insects. In this way, they can easily spread between countries and continents, thus posing a considerable quarantine threat. The biology of Ceratocystis spp. is such that diseases caused by this group of fungi are likely to become more common in the future.
Australasian Plant Pathology | 2006
G. C. Adams; Jolanda Roux; Michael J. Wingfield
Cytospora spp. (anamorphs of Valsa spp.) are common inhabitants of woody plants and they include important stem and branch canker pathogens. Isolates of these fungi were collected from diseased and healthy trees in South Africa. They were identified based on morphology and DNA sequence homology of the intertransgenic spacer ribosomal DNA. South African isolates were compared with isolates collected in other parts of the world, and they represented 25 genetically distinct sequences residing within the populations of 13–14 known species and three unique lineages. Several species are new records for South Africa, doubling previous reports of these fungi from the country. Similarities between South African isolates of Cytospora from non-native Eucalyptus, Malus, Pinus, Populus, Prunus and Salix species and isolates from Australia, Europe or America suggest that the fungal pathogens were imported with their hosts as endophytes. Isolates from indigenous Olea and Acacia appear to represent native populations. Host shifts were evident, including populations on Eucalyptus that also occurred on Mangifera, Populus, Sequoia, Tibouchina and Vitex. Isolates related to Valsa kunzei represent the first report of a Cytospora species on the widely cultivated timber tree, Pinus radiata. An identification key to Cytospora species in South Africa is included.