Parascedosporium and its relatives: phylogeny and ecological trends

The genus Scedosporium and its relatives comprising microascalean anamorphs with slimy conidia were studied. Graphium and Parascedosporium also belong to this complex, while teleomorphs are found in Pseudallescheria, Petriella, Petriellopsis, and Lophotrichus. Species complexes were clearly resolved by rDNA ITS sequencing. Significantly different ecological trends were observed between resolved species aggregates. The Pseudallescheria and Scedosporium prolificans clades were the only lineages with a marked opportunistic potential to mammals, while Petriella species were associated primarily with soil enriched by, e.g. dung. A consistent association with bark beetles was observed in the Graphium clade. The ex-type strain of Rhinocladium lesnei, CBS 108.10 was incorrectly implicated by Vuillemin (1910) in a case of human mycetoma; its sequence was identical to that of the ex-type strain of Parascedosporium tectonae, CBS 127.84

Ophiostomatales associated with wounds on hardwood trees in Poland

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Black root rot: a long known but little understood disease

Table S1. Hosts reported to be susceptible to black root rot infection.Table S2. Variation in host susceptibility to black root rot infection by the fungus formally known as Thielaviopsis basicola.Black root rot caused by the pathogen Thielaviopsis basicola has been known since the mid 1800s. The disease is important on many agricultural and ornamental plant species and has been found in at least 31 countries. Since its description, the pathogen has had a complex taxonomic history that has resulted in a confused literature. A recent revision of the Ceratocystidaceae following the advent of DNA sequencing technology has made it possible to resolve this confusion. Importantly, it has also shown that there are two pathogens in the Ceratocystidaceae that cause black root rot. They reside in the newly established genus Berkeleyomyces and are now known as B. basicola and B. rouxiae. This review considers the taxonomic history of the black root rot pathogens, and their global distribution. Prospects relating to the serious diseases that they cause and the likely impact that the era of genomics will have on our understanding of the pathogens are also highlighted.The University of Pretoria, the members of Tree Protection Co‐operative Programme (TPCP), the DST‐NRF Centre of Excellence in Tree Health Biotechnology (CTHB) and the National Research Foundation.https://onlinelibrary.wiley.com/journal/136530592020-06-01hj2019BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

Ceratocystis species, including two new taxa, from Eucalyptus trees in South Africa

The ascomycete genus Ceratocystis (Microascales, Ceratocystidaceae) includes important fungal pathogens of trees, including Eucalyptus species. Ceratocystis species and their Thielaviopsis asexual states are typically associated with insects, such as nitidulid beetles, that spread them over long distances. Eucalyptus trees comprise a substantial component of the forestry industry in South Africa, however, limited information is available regarding Ceratocystis species that infect these trees. In this study, Ceratocystis species were collected from wounds on Eucalyptus trees in all the major plantation regions of South Africa, as well as from insects associated with these wounds. Both morphology and multigene DNA sequence analyses, using three nuclear loci, were used to identify the Ceratocystis species. Of the 260 isolates collected, nine Ceratocystis species, of which two were represented only by their Thielaviopsis anamorph states were identified. These species were C. eucalypticola, C. pirilliformis, C. savannae, C. oblonga, C. moniliformis, T. basicola, T. thielavioides and two Ceratocystis species that are described here as C. salinaria sp. nov. and C. decipiens sp. nov. Insects associated with these Ceratocystis species were Brachypeplus depressus (Nitidulidae), Carpophylus bisignatus, C. dimidiatus (Nitidulidae), Xyleborus affinis (Scolytidae), Litargus sp. (Mycetophagidae) and a Staphylinid (Staphylinidae) species.National Research Foundation of South Africa (NRF), the THRIP Initiative of the Department of Trade and Industry (THRIP/DST), members of the Tree Protection Cooperative Programme (TPCP) and the University of Pretoria.http://link.springer.com/journal/13313hb201

Ophiostomatoid fungi associated with mangroves in South Africa, including Ophiostoma palustre sp. nov.

Mangrove trees are continuously under stress due to environmental and/or anthropogenic pressures, which expose them to attack by pathogens, compromising their survival. Ophiostomatoid fungi cause sap stain and diseases of a wide spectrum of tree species globally. These fungi infect trees through natural, insect, animal and/or human made wounds. During routine surveys of mangrove trees in South Africa, wounds on branches and stems of Avicennia marina were regularly monitored for the presence of ophiostomatoid fungi at ten study sites in the country. The stems of four mangrove species, A. marina, Bruguiera gymnorrhiza, Rhizophora mucronata and Barringtonia racemosa were also wounded and evaluated for the appearance of these fungi. Ophiostomatoid fungi were obtained from the mangrove associate B. racemosa, but not from any of the true mangroves. Analyses of DNA sequence data for the internal transcribed spacer, β-tubulin, calmodulin and translation elongation factor gene regions revealed that the fungi isolated from the wounds on B. racemosa belong to three species in the Ophiostomataceae, including a new taxon described here as Ophiostoma palustre sp. nov. These results suggest that the mangrove associate B. racemosa is more prone to colonization by ophiostomatoid fungi than the true mangroves.The Department of Science and Technology (DST) and National Research Foundation (NRF) Center of Excellence in Tree Health Biotechnology (CTHB).http://link.springer.com/journal/104822017-12-30Microbiology and Plant PathologyForestry and Agricultural Biotechnology Institute (FABI)Plant Production and Soil Scienc