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1.
Plant Dis ; 106(7): 1935-1943, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35084944

ABSTRACT

Brown spot needle blight (BSNB), caused by the fungal pathogen Lecanosticta acicola, is a well-known disease of Pinus spp. in several northern hemisphere countries. In the southern hemisphere, this disease has been reported only in Colombia and, apart from a single report of severe defoliation of Pinus radiata plantations in the early 1980s, has not caused serious damage in this country. An outbreak of a disease resembling BSNB on Mesoamerican Pinus spp. grown in Colombia has raised concern that L. acicola may have reemerged as a pathogen. DNA sequence-based analyses for the internal transcribed spacers, translation elongation factor 1-α and RNA polymerase II second largest subunit regions showed that the outbreaks were caused by L. pharomachri, a species distinct from, but closely related to, L. acicola. The discovery of L. pharomachri in Colombia is the first incidence of the pathogen causing a serious disease problem and the first occurrence on the hosts P. patula and P. maximinoi. A sexual state for L. pharomachri was discovered for the first time, and the description of the species has thus been emended.


Subject(s)
Pinus , Ascomycota , Colombia , Pinus/microbiology , Plant Diseases/microbiology
2.
Antonie Van Leeuwenhoek ; 113(6): 803-823, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32086683

ABSTRACT

Non-native Acacia plantations in Indonesia were first reported to be infested by a native ambrosia beetle species, identified as Euwallacea fornicatus in 1993. Recently the level of infestation in these plantations by ambrosia beetles has steadily increased. The recent redefinition of the taxonomic parameters of the Euwallacea fornicatus species complex has resulted in the identity of the ambrosia beetle species in these plantations becoming unclear. This is also true for their obligate fungal associates. Therefore, the aim of this study was to identify the ambrosia beetle species, as well as its corresponding fungal associate/s, infesting Acacia crassicarpa plantations in Riau, Indonesia. Morphological identification and phylogenetic analysis of the mitochondrial cytochrome oxidase c subunit I (COI) gene, revealed that the beetles are E. perbrevis, previously a synonym of E. fornicatus and commonly referred to as the Tea Shot Hole Borer A (TSHBa). Multi-locus phylogenetic analyses of the fungal associate of E. perbrevis revealed a Fusarium sp. that is among members of the Ambrosia Fusarium Clade (AFC), but that is genetically distinct from other previously identified Fusarium symbionts of Euwallacea species. This novel fungal species is described here as Fusarium rekanum sp. nov.


Subject(s)
Fusarium , Weevils/microbiology , Acacia , Animals , Coleoptera , Fusarium/classification , Fusarium/genetics , Fusarium/isolation & purification , Genes, Fungal , Indonesia , Phylogeny , Plants , Symbiosis
3.
Sydowia ; 69: 229-264, 2017.
Article in English | MEDLINE | ID: mdl-29386695

ABSTRACT

The present study introduces seven new species, one new combination, one new variety and several interesting taxonomical notes and/or geographical records. Most of the new taxa are Ascomycetes, but the study also includes a new variety of a Basidiomycete. Novel species include Gyromitra khanspurensis (Discinaceae, Pezizales, Pezizomycetes) from Pakistan growing near Cedrus deoadara and Paramyrothecium guiyangense and Paramyrothecium verruridum (Stachybotriaceae, Hypocreales, Sordariomycetes) both isolated from soil in China. New species from South Africa are Sclerostagonospora elegiae on culm litter of Elegia equisetacea, Sclerostagonospora fusiformis on culm litter of Thamnochortus spicigerus, Sclerostagonospora pinguis on culm litter of Cannomois virgata and Sclerostagonospora sulcata on culm litter of Ischyrolepis subverticellata (Phaeosphaeriaceae, Pleosporales, Dothideomycetes). Hapalocystis berkeleyi var. kickxii with its basionym Hypoxylon kickxii is shown to be a taxon on species level and thus recombined as Hapalocystis kickxii (Sydowiellaceae, Diaporthales, Sordariomycetes), and it is lecto- and epitypified. The new variety Pluteus romellii var. luteoalbus (Pluteaceae, Agaricales, Agaricomycetes) growing on a mossy fallen stem of a deciduous tree is described from Czech Republic. Cortinarius scaurocaninus (Cortinariaceae, Agaricales, Agaricomycetes) is new for Austria, Humicola grisea (Chaetomiaceae, Sordariales, Sordariomycetes) is an interesting new record for Chile. Two taxa are reported as new for Turkey: the lichenicolous fungus Opegrapha parasitica (Opegraphaceae, Arthoniales, Arthoniomycetes) growing partly immersed in the thallus of Aspicilia and the lichen Rinodina zwackhiana (Physciaceae, Teloschistales, Lecanoromycetes) from calcareous rock. Finally, Xerula strigosa (Physalacriaceae, Agaricales, Agaricomycetes), described from China, is confirmed to be present also in Pakistan.

4.
MycoKeys ; 94: 17-35, 2022.
Article in English | MEDLINE | ID: mdl-36760540

ABSTRACT

Eucalyptus spp. are widely planted in Colombia as an important component of a growing paper and pulp industry. Leaf and shoot blight caused by Calonectria spp. was one of the first disease problems to emerge in these plantations. A survey of Eucalyptus plantations in four forestry regions of Colombia during 2016 resulted in a large number of Calonectria isolates from soil samples collected in the understories of trees having symptoms of Calonectria leaf and shoot blight. The aim of this study was to identify and resolve the phylogenetic relationships for these isolates using DNA sequence comparisons of six gene regions as well as morphological characters. From a collection of 107 isolates, seven Calonectria species residing in three species complexes were identified. Two of these represented undescribed species, namely C.exiguispora sp. nov. and C.guahibo sp. nov. Calonectriaparvispora and C.spathulata were the most commonly isolated species, each of which accounted for approximately 30% of the isolates. The results suggest that Colombia has a wide diversity of Calonectria spp. and that these could challenge Eucalyptus plantation forestry in the future.

5.
Mycobiology ; 48(4): 245-251, 2020 Jun 02.
Article in English | MEDLINE | ID: mdl-32952407

ABSTRACT

During a survey of putative fungal pathogens infecting oak trees in the Gangwon Province of the Republic of Korea, a fungus resembling a Ceratocystis sp. was repeatedly isolated from natural wounds on Quercus variabilis. Morphological comparisons and DNA sequence comparisons based on partial ß-tubulin and TEF-1α gene regions showed that the fungus resided in a distinct lineage. This novel Ceratocystis species is described here as C. quercicola sp. nov. This is the first novel species of Ceratocystis to be reported from Korea. A pathogenicity test showed that it can cause lesions on inoculated trees but that it had a very low level of aggressiveness. The discovery of this fungus suggests that additional taxa residing in Ceratocystis are likely to be discovered in Korea in the future.

6.
Mycologia ; 112(6): 1240-1262, 2020.
Article in English | MEDLINE | ID: mdl-32634330

ABSTRACT

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


Subject(s)
Coleoptera/microbiology , Ophiostomatales/classification , Ophiostomatales/genetics , Phylogeny , Tracheophyta/microbiology , Animals , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Norway , Ophiostomatales/isolation & purification , Poland , RNA, Ribosomal/genetics , Russia , Spores, Fungal , Weevils/microbiology
7.
MycoKeys ; 69: 33-52, 2020.
Article in English | MEDLINE | ID: mdl-32733148

ABSTRACT

Huntiella species are wood-infecting, filamentous ascomycetes that occur in fresh wounds on a wide variety of tree species. These fungi are mainly known as saprobes although some have been associated with disease symptoms. Six fungal isolates with typical culture characteristics of Huntiella spp. were collected from wounds on native forest trees in Greece and South Africa. The aim of this study was to identify these isolates, using morphological characters and multigene phylogenies of the rRNA internal transcribed spacer (ITS) region, portions of the ß-tubulin (BT1) and translation elongation factor 1α (TEF-1α) genes. The mating strategies of these fungi were also determined through PCR amplification of mating type genes. The study revealed two new species; one from Platanus orientalis in Greece and one from Colophospermum mopane and Senegalia nigrescens in South Africa. These novel taxa have been provided with the names, H. hellenica sp. nov. and H. krugeri sp. nov., respectively. The former species was found to have a homothallic and the latter a heterothallic mating system.

8.
MycoKeys ; 76: 49-79, 2020.
Article in English | MEDLINE | ID: mdl-33505197

ABSTRACT

Syzygium jambos (Myrtales, Myrtaceae) trees in Hawaii are severely affected by a rust disease caused by Austropuccinia psidii (Pucciniales, Sphaerophragmiaceae), but they are commonly co-infected with species of Cryphonectriaceae (Diaporthales). In this study, S. jambos and other trees in the Myrtales were examined on three Hawaiian Islands for the presence of Cryphonectriaceae. Bark samples with fruiting bodies were collected from infected trees and fungi were isolated directly from these structures. Pure cultures were produced and the fungi were identified using DNA sequence data for the internal transcribed spacer (ITS) region, part of the ß-tubulin (BT1) gene and the transcription elongation factor-1α (TEF1) gene. Five species in three genera of Cryphonectriaceae were identified from Myrtaceae tree samples. These included Chrysoporthe deuterocubensis, Microthia havanensis and three previously-unknown taxa described here as Celoporthe hauoliensis sp. nov., Cel. hawaiiensis sp. nov. and Cel. paradisiaca sp. nov. Representative isolates of Cel. hauoliensis, Cel. hawaiiensis, Cel. paradisiaca, Chr. deuterocubensis and Mic. havanensis were used in artificial inoculation studies to consider their pathogenicity on S. jambos. Celoporthe hawaiiensis, Cel. paradisiaca and Chr. deuterocubensis produced lesions on young S. jambos trees in inoculation trials, suggesting that, together with A. psidii, they may contribute to the death of trees. Microsatellite markers were subsequently used to consider the diversity of Chr. deuterocubensis on the Islands and thus to gain insights into its possible origin in Hawaii. Isolates of this important Myrtaceae and particularly Eucalyptus pathogen were found to be clonal. This provides evidence that Chr. deuterocubensis was introduced to the Hawaiian Islands as a single introduction, from a currently unknown source.

9.
Fungal Biol ; 123(11): 783-790, 2019 11.
Article in English | MEDLINE | ID: mdl-31627854

ABSTRACT

Acacia koa and A. heterophylla are commonly occurring native trees on the Hawaiian Islands and La Réunion, respectively. A recent phylogenetic study suggested that A. heterophylla renders A. koa paraphyletic, and that the former likely arose from the Hawaiian Islands around 1.4 million years ago. An intriguing question is whether their microbiota is similar, although they occur naturally in two very distant geographical locations. In this study, we compared the fungi in the Botryosphaeriaceae isolated from natural populations of A. koa and A. heterophylla. These fungi were chosen because they commonly occur on woody plants and some are important pathogens. They are also known to have been moved globally on asymptomatic plant materials. Isolates were identified based on comparisons of DNA sequence data for the rDNA-ITS, TEF1-α and ß-tubulin loci. Ten Botryosphaeriaceae species were identified, of which four species were specific to A. koa from the Hawaiian Islands and five to A. heterophylla in La Réunion. Only one species, Neofusicoccumparvum, which is known to have a wide global distribution, was common to both hosts. The overall results of this study suggest that although A. koa and A.heterophylla share a recent evolutionary history, they have established independent microbiota, at least in terms of the Botryosphaeriaceae.


Subject(s)
Acacia/microbiology , Ascomycota/classification , Ascomycota/isolation & purification , Biodiversity , Ascomycota/genetics , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Hawaii , Peptide Elongation Factor 1/genetics , Phylogeny , Reunion , Sequence Analysis, DNA , Tubulin/genetics
10.
Fungal Biol ; 122(9): 900-910, 2018 09.
Article in English | MEDLINE | ID: mdl-30115324

ABSTRACT

Ophiostoma quercus (Ascomycota, Ophiostomatales) is a globally widespread, insect-vectored fungus that colonizes a wide diversity of hardwood and conifer hosts. Although the fungus is considered to be non-pathogenic, it is closely related to the fungi that cause Dutch elm disease. We examined the global diversity of O. quercus based on a ribosomal RNA marker and three unlinked gene regions. The fungus exhibited substantial morphological diversity. In addition, O. quercus had high genetic diversity in every continent from which it was collected, although the fungus was most diverse in Eurasia. There was no evidence of geographical clustering of haplotypes based on phylogenetic and network analyses. In addition, the phylogenetic trees generated based on the different markers were non-congruent. These results suggest that O. quercus has been repeatedly moved around the globe, because of trade in wood products, and that the fungal species most likely outcrosses regularly. The high genetic diversity of the fungus, as well as its ability to utilize a wide variety of arthropod vectors and colonize a tremendous diversity of tree host species makes O. quercus truly unique among ophiostomatoid fungi.


Subject(s)
Ophiostoma/classification , Ophiostoma/genetics , Trees/microbiology , Animals , DNA, Fungal/genetics , Phylogeography , RNA, Ribosomal , Sequence Analysis, DNA
11.
Fungal Biol ; 120(11): 1323-1340, 2016 11.
Article in English | MEDLINE | ID: mdl-27742092

ABSTRACT

There have been many recent studies using environmental nucleic acid sequences (ENAS) to assess fungal diversity. As a result, more than a third of all fungal sequences in GenBank are of environmental origin. But inconsistent annotation of the thousands of undescribed taxa represented by these sequences limits access to these data. Consequently, these ENAS and the taxa they represent are rarely considered in other studies, and especially not in taxonomic treatments. This problem is confounded by the fact that the current version of the International Code of Nomenclature for Algae, Fungi, and Plants (Melbourne Code) prohibits the description of novel taxa known only from ENAS. There have been suggestions to emend the Code to allow a systematic nomenclatural treatment of these currently 'orphan' taxa but this has yet to occur. In this study, we considered the feasibility of using sequences from environmental studies to resolve the generic status of Sporothrix lignivora. This species forms a single lineage distinct from Sporothrix and other genera in the Ophiostomatales. BLAST searches in GenBank using LSU and ITS sequences of S. lignivora corresponded with several sequences from environmental studies. This also led to the discovery of isolates collected in diversity studies based on culturable fungi, with high similarity to S. lignivora. Phylogenetic analyses including taxa representing all major genera and lineages in the Ophiostomatales revealed a distinct, well-supported lineage that included S. lignivora and the ENAS. This confirmed the presence of a new genus in the Ophiostomatales described here as Hawksworthiomyces gen. nov., with S. lignivora as type species. Whereas only one described species was known in the so-called S. lignivora complex, our analyses revealed nine additional lineages in what is now Hawksworthiomyces. For three of these lineages, we were able to obtain isolates and these are described as Hawksworthiomyces taylorii sp. nov., Hawksworthiomyces crousii sp. nov., and Hawksworthiomyces hibbettii sp. nov. Five of the lineages each included one or more sequences from single studies, and thus remain unnamed. The remaining lineage included two sequences from separate studies of fungi inhabiting conifer wood. One of these sequences was an uncultured fungus clone from a spruce log in Sweden. The other sequence was for an isolate from a western red cedar fencepole in British Columbia, Canada, that was subsequently lost. These two ITS sequences differ in only two nucleotide positions. We are confident that they represent the same taxon and meet the criteria for an ENAS species, for which we provide the name, Hawksworthiomyces sequentia sp. nov. ENAS, and designate a DNA sequence as type in the absence of a type specimen. This case study makes it clear that environmental sequences and those from lost isolates can be extremely valuable in phylogeny-based taxonomic studies. It emphasises the fact that the Code should be emended to enable the naming of such taxa in a manner that will facilitate their incorporation in other studies.


Subject(s)
Coleoptera/microbiology , DNA, Fungal/genetics , Ophiostomatales/classification , Ophiostomatales/isolation & purification , Plants/microbiology , Animals , DNA, Ribosomal Spacer/genetics , Molecular Sequence Data , Ophiostomatales/genetics , Phylogeny
12.
IMA Fungus ; 6(1): 249-56, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26203427

ABSTRACT

Jacaranda mimosifolia trees have been progressively dying due to Ganoderma root and butt rot disease in Pretoria (the "City of Jacarandas") for many years. Ganoderma austroafricanum was described from these trees previously but this was based on a single collection. This study treats a substantially expanded collection of isolates of Ganoderma made from all dying trees where basidiomes were present in a Pretoria suburb. DNA sequences were obtained from the ITS and LSU region for the isolates and compared against sequences on GenBank. Phylogenetic analyses were used to compare sequences with those for other Ganoderma species. Based on sequence comparisons and morphological characters, two new Ganoderma species were discovered and these are described here as G. enigmaticum and G. destructans spp. nov. Interestingly, the previously described G. austroafricanum was not found, G. enigmaticum was found on only one Ceratonia siliqua tree and G. destructans was found on all other trees sampled. The latter species appears to be the primary cause of root rot of J. mimosifolia in the area sampled.

13.
IMA Fungus ; 6(2): 257-62, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26734541

ABSTRACT

Itajahya is a member of Phallales (Agaricomycetes), which, based on the presence of a calyptra and DNA sequence data for I. rosea, has recently been raised to generic status from a subgenus of Phallus. The type species of the genus, I. galericulata, is commonly known as the Jacaranda stinkhorn in Pretoria, South Africa, which is the only area where the fungus is known outside the Americas. The common name is derived from its association with the South American originating Jacaranda mimosifolia trees in the city. The aim of this study was to consider the unusual occurrence of the fungus in South Africa, to place it on the available Phallales phylogeny and to test whether it merits generic status. Fresh basidiomes were collected during the summer of 2015 and sequenced. Phylogenetic analyses were based on sequence data for the nuc-LSU-rDNA (LSU) and ATPase subunit 6 (ATP6) regions. The results showed that I. rosea and I. galericulata are phylogenetically related. They are also clearly distinguished from other members of Phallales such as Phallus spp. and Dictyophora spp., and so our new data supports the raising of Itajahya to the generic level.

14.
Fungal Biol ; 119(7): 615-30, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26058537

ABSTRACT

Little is known about the biology of the monotypic genus Cornuvesica (Microascales), apart from that isolates are notoriously difficult to culture on artificial media. A recent collection of material resembling this genus from freshly made wounds on Gmelina arborea in Indonesia, provided an opportunity to reconsider all available material of Cornuvesica falcata, type species of the genus. In addition to morphological comparisons, multigene phylogenetic analyses were made using sequences of the SSU, ITS, LSU and TEF-1α genes. Our results showed that the holotype of Cor. falcata from pine in Canada differed from all other material previously considered to represent this species and also from the new Indonesian collections. The collections considered represented three additional species that we describe here as new. Three New Zealand isolates and an isolate from UK were respectively described as Cor. acuminata and Cor. crypta, while the Indonesian isolates were described as Cor. magnispora. Phylogenies based on the SSU and LSU data sets showed that Cornuvesica spp. do not belong in the Ceratocystidaceae as previously suggested, but represent a distinct lineage in the Microascales that has yet to be named. Results showed that culture filtrates from other fungi or ferric chloride markedly stimulated the growth of Cor. magnispora.


Subject(s)
Lamiaceae/microbiology , Ophiostomatales/isolation & purification , DNA, Fungal/genetics , DNA, Ribosomal/genetics , Molecular Sequence Data , Ophiostomatales/classification , Ophiostomatales/genetics , Ophiostomatales/growth & development , Phylogeny , Plant Bark/microbiology
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