Wen-Ying Zhuang

Genera in Bionectriaceae, Hypocreaceae, and Nectriaceae (Hypocreales) proposed for acceptance or rejection.

With the recent changes concerning pleomorphic fungi in the new International Code of Nomenclature for algae, fungi, and plants (ICN), it is necessary to propose the acceptance or protection of sexual morph-typified or asexual morph-typified generic names that do not have priority, or to propose the rejection or suppression1 of competing names. In addition, sexual morph-typified generic names, where widely used, must be proposed for rejection or suppression in favour of asexual morph-typified names that have priority, or the latter must be proposed for conservation or protection. Some pragmatic criteria used for deciding the acceptance or rejection of generic names include: the number of name changes required when one generic name is used over another, the clarity of the generic concept, their relative frequencies of use in the scientific literature, and a vote of interested mycologists. Here, twelve widely used generic names in three families of Hypocreales are proposed for acceptance, either by conservation or protection, despite their lack of priority of publication, or because they are widely used asexual morph-typified names. Each pair of generic names is evaluated, with a recommendation as to the generic name to be used, and safeguarded, either through conservation or protection. Four generic names typified by a species with a sexual morph as type that are younger than competing generic names typified by a species with an asexual morph type, are proposed for use. Eight older generic names typified by species with an asexual morph as type are proposed for use over younger competing generic names typified by a species with a sexual morph as type. Within Bionectriaceae, Clonostachys is recommended over Bionectria; in Hypocreaceae, Hypomyces is recommended over Cladobotryum, Sphaerostilbella over Gliocladium, and Trichoderma over Hypocrea; and in Nectriaceae, Actinostilbe is recommended over Lanatonectria, Cylindrocladiella over Nectricladiella, Fusarium over Gibberella, Gliocephalotrichum over Leuconectria, Gliocladiopsis over Glionectria, Nalanthamala over Rubrinectria, Nectria over Tubercularia, and Neonectria over Cylindrocarpon.

Botrytis fabiopsis, a new species causing chocolate spot of broad bean in central China

The current study was conducted to identify Botrytis spp. isolated from symptomatic broad bean plants grown in Hubei Province, China. Among 184 Botrytis strains, three distinct species, B. cinerea, B. fabae and a previously undescribed Botrytis sp., were identified based on morphology of colonies, sclerotia and conidia. The novel Botrytis sp. is described herein as a new species, Botrytis fabiopsis sp. nov. At 20 C B. fabiopsis grew on potato dextrose agar (PDA) at 12–13 mm d−1, similar to B. fabae (13 mm d−1), but slower than B. cinerea (17–19 mm d−1). It formed pale gray colonies with short aerial mycelia and produced gray to black sclerotia in concentric rings on PDA. B. fabiopsis produced greater numbers of sclerotia than B. cinerea but fewer than B. fabae. Conidia produced by B. fabiopsis on broad bean leaves are hyaline to pale brown, elliptical to ovoid, wrinkled on the surface and are larger than conidia of B. fabae and B. cinerea. Phylogenetic analysis based on combined DNA sequence data of three nuclear genes (G3PDH, HSP60 and RPB2) showed that B. fabiopsis is closely related to B. galanthina, the causal agent of gray mold disease of Galanthus sp., but distantly related to B. fabae and B. cinerea. Sequence analysis of genes encoding necrosis and ethylene-inducing proteins (NEPs) indicated that B. fabiopsis is distinct from B. galanthina. Inoculation of broad bean leaves with conidia of B. fabiopsis caused typical chocolate spot symptoms with a similar disease severity to that caused by B. fabae but significantly greater than that caused by B. cinerea. This study suggests that B. fabiopsis is a new causal agent for chocolate spot of broad bean.

Morphological and phylogenetic identification of Botrytis sinoviticola, a novel cryptic species causing gray mold disease of table grapes (Vitis vinifera) in China.

Seventy-five isolates of Botrytis collected from table grapes (Vitis vinifera) with gray mold symptoms in China were identified based on morpho-cultural characteristics on potato dextrose agar (20 C) and/or phylogenetic analysis using the sequences of three nuclear genes (G3PDH, HSP60, RPB2). Isolates of different species of Botrytis were compared with fenhexamid sensitivity, Bc-hch gene-RFLP haplotyping and pathogenicity to V. vinifera. The 75 isolates comprise two species, B. cinerea (63 isolates) and an undescribed Botrytis sp. (12 isolates) described here as Botrytis sinoviticola Zhang et al. sp., nov. Both B. sinoviticola (Bs) and B. cinerea (Bc) were found to have 20 C optimum for mycelial growth and 25 C for conidial germination. Sensitivity to fenhexamid was significantly greater (P < 0.05) for Bc (EC50 = 0.04 ± 0.01 μg mL−1) than for Bs (EC50 = 0.08 ± 0.02 μg mL−1). Digestion of the PCR amplicons of the Bc-hch gene with Hha I generated two haplotypes, Group I haplotype for Bs and Group II haplotype for Bc. Bs infected table grapes (leaves, berries) only through wounds, whereas Bc infected both injured and non-injured tissues of table grapes. This study suggests that Bs is a cryptic species sympatric with Bc on table grapes in China.

Practice towards DNA barcoding of the nectriaceous fungi

Fungi of Nectriaceae are economically important and of high species diversity. For the purpose of accurate and rapid species identification, ITS, 28S rDNA, β-tubulin gene and EF-1α gene were selected as the candidate DNA barcode markers to investigate their feasibility in identification of 28 well-circumscribed species belonging to 9 genera of the nectriaceous fungi. A total of 216 sequences of the candidate genes were analyzed. Intra- and inter-specific variations and success rate of PCR amplification and sequencing were considered as important criteria to estimate the candidate genes. The partial β-tubulin gene met the requirements for an ideal DNA barcode and functions well for correct species delimitation. No overlapping between the intra- and inter-specific pairwise distances was found. The smallest inter-specific distance of β-tubulin gene was 3.45%, while the largest intra-specific distance was 2.77%; which appeared to possess the appropriate intra- and inter-specific variations. Twenty-eight clusters were recognized in accordance with the 28 morphological species tested. In addition, it had a high PCR and sequencing success rate. As to the other candidates, EF-1α gene showed fairly good sequence variations among species, but the PCR and sequencing success rate reached only 75.3%. ITS had a high PCR and sequencing success rate (93.5%) and recognizes 92.9% of the total number of species, nevertheless, overlapping occurred between the intra- and inter-specific distances, which may lead to incorrect species identification. 28S rDNA is most conservative compared with any other candidate markers and able to recognize merely 60.7% of the total species. We propose β-tubulin gene as the possible barcode for the nectriaceous fungi.

Chaetopsinectria (Nectriaceae, Hypocreales), a new genus with Chaetopsina anamorphs

Genus Chaetopsinectria is established to accommodate four species, previously assigned to Cosmospora, that possess Chaetopsina anamorphs, small and red perithecia not collapsing when dry, a typical Cosmospora perithecial wall structure, clavate asci, smooth or striate ascospores, sienna colonies on PDA, and on decaying debris or woody substrates. The segregation of the new genus from Cosmospora is well supported by sequence analyses of nuclear ribosomal DNA (ITS and 28S partial) with maximum parsimony and Bayesian methods. The molecular data indicate that the new genus is distantly related to Cosmospora coccinea Rabenh., the type species of Cosmospora sensu stricto, and its related fungi. Four new combinations, Chaetopsinectria chaetopsinae, C. chaetopsinae-catenulatae, C. chaetopsinae-penicillatae and C. chaetopsinae-polyblastiae, are proposed.

DNA barcoding of the fungal genus Neonectria and the discovery of two new species.

To determine a suitable DNA barcode for the genus Neonectria, the internal transcribed spacer rDNA, β-tubulin, EF-1α, and RPB2 genes were selected as candidate markers. A total of 205 sequences from 19 species of the genus were analyzed. Intra- and inter-specific divergences and the ease of nucleotide sequence acquisition were treated as criteria to evaluate the feasibility of a DNA barcode. Our results indicated that any single gene among the candidate markers failed to serve as a successful barcode, while the combination of the partial EF-1α, and RPB2 genes recognized all species tested. We tentatively propose the combined partial EF-1α and RPB2 genes as a DNA barcode for the genus. During this study, two cryptic species were discovered, based on the combined data of morphology and DNA barcode information. We described and named these two new species N. ditissimopsis and N. microconidia.

Three new species of Trichoderma with hyaline ascospores from China

Collections of Trichoderma having hyaline ascospores from different areas of China were examined. Using combined analyses of morphological data, culture characters and phylogenetic information based on rDNA sequences of partial nuc translation elongation factor 1-α encoding gene (TEF1-α) and the gene encoding the second largest nuc RNA polymerase subunit (RPB2), three new species, Trichoderma applanatum, T. oligosporum and T. sinoluteum, were discovered and are described. Trichoderma applanatum produces continuous flat to pulvinate, white to cream stromata with dense orange or pale brown ostioles, and simple acremonium-like to verticillium-like conidiophores, belongs to the Hypocreanum clade and is closely related to T. decipiens. Trichoderma oligosporum forms reddish brown stromata with a downy surface, hyaline conidia and gliocladium-like conidiophores, and is closely related to but distinct from T. crystalligenum in the Psychrophila clade. Trichoderma sinoluteum, as a member of the Polysporum clade, is characterized by pale yellow stromata, white pustulate conidiomata, pachybasium-like conidiophores, and hyaline conidia. Differences between the new species and their close relatives are discussed.

Two new hyaline-ascospored species of Trichoderma and their phylogenetic positions

Collections of hypocrealean fungi found on decaying wood in subtropical regions of China were examined. Two new species, Trichoderma confluens and T. hubeiense, were discovered and are described. Trichoderma confluens is characterized by its widely effuse to rarely pulvinate, yellow stromata with densely disposed yellowish brown ostioles, simple acremonium- to verticillium-like conidiophores, hyaline conidia and multiform chlamydospores. Trichoderma hubeiense has pulvinate, grayish yellow stromata with brownish ostioles, trichoderma- to verticillium-like conidiophores and hyaline conidia. The phylogenetic positions of the two fungi were investigated based on sequence analyses of RNA polymerase II subunit b and translation elongation factor 1-α genes. The results indicate that T. confluens belongs to the Hypocreanum clade and is associated with but clearly separated from T. applanatum and T. decipiens. Trichoderma hubeiense belongs to the Polysporum clade and related to T. bavaricum but obviously differs from other members of the clade in sequence data. Morphological distinctions between the new species and their close relatives are noted and discussed.

Four new species of the genus Hymenoscyphus (fungi) based on morphology and molecular data

Four new species of Hymenoscyphus (H. brevicellulus, H. hyaloexcipulus, H. microcaudatus, and H. subsymmetricus) and a new Chinese record (H. subpallescens) are described. These five species share common characteristics: small apothecia (<3 mm in diameter); hymenium whitish, pale yellow, to yellow in color; ectal excipulum of textura prismatica; asci arising from simple septa; ascospores scutuloid and guttulate; saprophytic nutrition; and leaf habitats, except for H. subsymmetricus, which grows on herbaceous stems. Phylogenetic analyses of internal transcribed spacer nuclear ribosomal DNA sequences, the universal DNA barcode for fungi, for 16 species in the genus indicated that these taxa were closely related to H. microserotinus, in accordance with their morphological features, but represented independent species. The distinguishing features of each new species from its relatives are discussed, and their phylogenetic relationships explored.

Two new species of Unguiculariopsis ( Helotiaceae , Encoelioideae ) from China

Two new species of Unguiculariopsis are described from tropical Guangxi and the Changbai Mountains in northeastern China. Unguiculariopsis changbaiensis and its anamorph Deltosperma oblongum occurs on a pyrenomycete and U. damingshanica is lichenicolous.