Studies in the genus Glutinoglossum

Phylogeny and taxonomy of Catenularia and similar fungi with catenate conidia

The genus Catenularia (Chaetosphaeriaceae) was reviewed, and its relationships with morphologically similar fungi were evaluated using molecular and morphological data. Eleven species are accepted, four of which have been verified with molecular DNA data. The correct epithet ‘cupulifera’ is proposed for the type species C.cupuliferacomb. nov. Four other combinations are proposed, namely C.catenulatacomb. nov., C.elsikiicomb. nov., C.minorcomb. nov. and C.novae-zelandiaecomb. nov.Catenularia is an uncommon fungus inhabiting mainly decaying bark, wood and bamboo culms of various hosts and shows a widespread geographical distribution. It is circumscribed for fungi with mononematous, macronematous, simple conidiophores with terminal monophialides, usually accompanied with capitate hyphae. The conidia are aseptate, brown, cuneiform to rounded-obconic with an angular outline, adhering in chains. The diagnostic values of taxonomic characteristics of capitate hyphae and conidia (i.e. colour, shape in transverse section, setulae and formation) at the generic level were evaluated. An account of morphology, taxonomy and phylogeny of species accepted in Catenularia is provided. Based on ribosomal DNA sequences, Chalarodesobpyramidatasp. nov., characterised by catenate, angular, hyaline conidia with apical setulae, is revealed as closely related to Catenularia. The new genus Fuscocatenulagen. nov. is proposed for catenularia-like fungi having pigmented conidia with protracted maturation and round outline, with two species accepted, F.submersacomb. nov. and F.variegatacomb. nov. A new species Nawawiaantennatasp. nov. is introduced and Nawawia is compared with morphologically similar taxa.

Phylogeny, Global Biogeography and Pleomorphism of Zanclospora

Zanclospora (Chaetosphaeriaceae) is a neglected, phialidic dematiaceous hyphomycete with striking phenotypic heterogeneity among its species. Little is known about its global biogeography due to its extreme scarcity and lack of records verified by molecular data. Phylogenetic analyses of six nuclear loci, supported by phenotypic data, revealed Zanclospora as highly polyphyletic, with species distributed among three distantly related lineages in Sordariomycetes. Zanclospora is a pleomorphic genus with multiple anamorphic stages, of which phaeostalagmus-like and stanjehughesia-like are newly discovered. The associated teleomorphs were previously classified in Chaetosphaeria. The generic concept is emended, and 17 species are accepted, 12 of which have been verified with DNA sequence data. Zanclospora thrives on decaying plant matter, but it also occurs in soil or as root endophytes. Its global diversity is inferred from metabarcoding data and published records based on field observations. Phylogenies of the environmental ITS1 and ITS2 sequences derived from soil, dead wood and root samples revealed seven and 15 phylotypes. The field records verified by DNA data indicate two main diversity centres in Australasia and Caribbean/Central America. In addition, environmental ITS data have shown that Southeast Asia represents a third hotspot of Zanclospora diversity. Our data confirm that Zanclospora is a rare genus.

DNA barcode, multiplex PCR and qPCR assay for diagnosis of pathogens infecting pulse crops to facilitate safe exchange and healthy conservation of germplasm

The DNA barcodes were developed from ITS region for the identification of fungal plant pathogens namely, Alternaria alternata and A. tenuissima both causing leaf spots, Ascochyta rabiei causing Ascochyta blight, Fusarium oxysporum f. sp. ciceris causing wilt, Macrophomina phaseolina causing dry root rot, Rhizoctonia solani causing web blight and wet root rot, Sclerotium (Athelia) rolfsii causing collar rot, Sclerotinia sclerotiorum causing stem rot and Cercospora canescens and Pseudocercospora cruenta both causing leaf spots in pulse crops. Barcode compliance for A. alternata (DBTPQ001-18), A. tenuissima (DBTPQ002-18), A. rabiei (DBTPQ003-18), F. oxysporum f. sp. ciceris (DBTPQ004-18), M. phaseolina (DBTPQ005-18), R. solani (DBTPQ006-18), S. rolfsii (DBTPQ007-18), S. sclerotiorum (DBTPQ008-18), C. canescens (DBTPQ009-18) and P. cruenta (DBTPQ029-20) have been generated based on the Barcode of Life Data System (BOLD) system. In addition to ITS, other genomic regions were also explored and on the basis of sequence variation they were ranked as TEF-α > SSU > LSU > β-tubulin. These genes could be considered for secondary barcode and phylogenetic relatedness. ITS-based markers for the detection of A. alternata (BAA2aF and BAA2aR) and R. solani (BRS17cF and BRS17cR) were developed which provided 400 bp and 220 bp amplicons, respectively. While, for F. oxysporum f. sp. ciceris, COX1-based marker (FOCox1F and FOCox3R) was developed which amplified 150 bp. The markers proved highly specific and sensitive with detection limit of 0.0001 ng of template DNA using qPCR and simultaneously detected these three pathogens. The DNA barcodes and diagnostics developed are suitable for quick and reliable detection of these pathogens during quarantine processing and field diagnostics.

Delimitation, new species and teleomorph-anamorph relationships in Codinaea, Dendrophoma, Paragaeumannomyces and Striatosphaeria (Chaetosphaeriaceae)

The Chaetosphaeriaceae are a diverse group of pigmented, predominantly phialidic hyphomycetes comprised of several holomorphic genera including Chaetosphaeria, the most prominent genus of the family. Although the morphology of the teleomorphs of the majority of Chaetosphaeria is rather uniform, their associated anamorphs primarily exhibit the variability and evolutionary change observed in the genus. An exception from the morphological monotony among Chaetosphaeria species is a group characterised by scolecosporous, hyaline to light pink, multiseptate, asymmetrical ascospores and a unique three-layered ascomatal wall. Paragaeumannomyces sphaerocellularis, the type species of the genus, exhibits these morphological traits and is compared with similar Chaetosphaeria with craspedodidymum- and chloridium-like synanamorphs. Morphological comparison and phylogenetic analyses of the combined ITS-28S sequences of 35 isolates and vouchers with these characteristics revealed a strongly-supported, morphologically well-delimited clade in the Chaetosphaeriaceae containing 16 species. The generic name Paragaeumannomyces is applied to this monophyletic clade; eight new combinations and five new species, i.e. P. abietinus sp. nov., P. elegans sp. nov., P. granulatus sp. nov., P. sabinianus sp. nov. and P. smokiensis sp. nov., are proposed. A key to Paragaeumannomyces is provided. Using morphology, cultivation studies and phylogenetic analyses of ITS and 28S rDNA, two additional new species from freshwater and terrestrial habitats, Codinaea paniculata sp. nov. and Striatosphaeria castanea sp. nov., are described in the family. A codinaea-like anamorph of S. castanea forms conidia with setulae at each end in axenic culture; this feature expands the known morphology of Striatosphaeria. A chaetosphaeria-like teleomorph is experimentally linked to Dendrophoma cytisporoides, a sporodochial hyphomycete and type species of Dendrophoma, for the first time.

Towards an understanding of the genus Glutinoglossum with emphasis on the Glutinoglossum glutinosum species complex (Geoglossaceae, Ascomycota)

Glutinoglossum is one of the earth tongue genera with viscid or glutinous ascocarps. Based on morphology and ITS1-5.8S-ITS2, nrLSU and tef1 sequence data, seven new species are described: G. circinatum, G. lumbricale, G. orientale, G. peregrinans, G. proliferatum, G. pseudoglutinosum, and G. triseptatum. The lectotypes for Geoglossum glutinosum var. lubricum and for Geoglossum glabrum var. majus as well as the epitype for Glutinoglossum glutinosum are designated. The comprehensive morphological study of G. heptaseptatum resulted in the discovery of ascospores germinating by conidia inside the asci, which is first noted for Glutinoglossum species. The status of Cibalocoryne is discussed.

Fungal Identification Using Molecular Tools: A Primer for the Natural Products Research Community

Fungi are morphologically, ecologically, metabolically, and phylogenetically diverse. They are known to produce numerous bioactive molecules, which makes them very useful for natural products researchers in their pursuit of discovering new chemical diversity with agricultural, industrial, and pharmaceutical applications. Despite their importance in natural products chemistry, identification of fungi remains a daunting task for chemists, especially those who do not work with a trained mycologist. The purpose of this review is to update natural products researchers about the tools available for molecular identification of fungi. In particular, we discuss (1) problems of using morphology alone in the identification of fungi to the species level; (2) the three nuclear ribosomal genes most commonly used in fungal identification and the potential advantages and limitations of the ITS region, which is the official DNA barcoding marker for species-level identification of fungi; (3) how to use NCBI-BLAST search for DNA barcoding, with a cautionary note regarding its limitations; (4) the numerous curated molecular databases containing fungal sequences; (5) the various protein-coding genes used to augment or supplant ITS in species-level identification of certain fungal groups; and (6) methods used in the construction of phylogenetic trees from DNA sequences to facilitate fungal species identification. We recommend that, whenever possible, both morphology and molecular data be used for fungal identification. Our goal is that this review will provide a set of standardized procedures for the molecular identification of fungi that can be utilized by the natural products research community.