Resolving the Phoma enigma

High Diversity of Epicoccum Species Associated with Leaf Spot on Italian Ryegrass in Southwestern China: Six New Records and Three New Species

Italian ryegrass is widely cultivated for the production of forage, hay, and silage because of its high nutritional value and good palatability. Leaf spots caused by fungi pose a serious threat to forage crops. In order to expand the knowledge of fungi causing leaf spots in ryegrass (Lolium multiflorum) in Sichuan, Yunnan, Chongqing, and Guizhou of southwestern China, a comprehensive survey was undertaken from 2015 to 2022. The survey discovered that Epicoccum leaf spot (ELS) was a common and widespread disease, more serious at the late stage of growth (after late May). Symptomatic leaf samples collected from the four different provinces were analyzed, and a total of 202 Epicoccum isolates were obtained. Based on both multilocus phylogeny (ITS, LSU, TUB2, and RPB2) and morphology, 10 Epicoccum species were finally identified, including three novel species (E. endololii sp. nov., E. lolii sp. nov., and E. loliicola sp. nov.), six new host records (E. draconis, E. endophyticum, E. oryzae, E. plurivorum, E. thailandicum, and E. tobaicum), and an unknown species (Epicoccum sp.1). Pathogenicity tests showed that E. endophyticum, E. endololii, and Epicoccum sp.1 were nonpathogenic to Italian ryegrass, which were confirmed as endophytes in this study; the other six species could infect Italian ryegrass and cause leaf lesions to different degrees, of which E. draconis was more aggressive (P ≤ 0.05). Coupled with the isolation rates and geographical distributions of these species, it was found that E. plurivorum was the predominant pathogen in Yunnan while E. oryzae and E. tobaicum were the predominant pathogens in the other three provinces. This work provides an initial understanding of the taxonomy, virulence, and distribution of Epicoccum species associated with ELS in southwestern China and lays a solid foundation for the diagnosis in the field and scientific control of ELS on Italian ryegrass.

Exploring ascomycete diversity in Yunnan II: Introducing three novel species in the suborder Massarineae (Dothideomycetes, Pleosporales) from fern and grasses

This article presents the results of an ongoing inventory of Ascomycota in Yunnan, China, carried out as part of the research project series "Exploring ascomycete diversity in Yunnan". From over 100 samples collected from diverse host substrates, microfungi have been isolated, identified and are currently being documented. The primary objective of this research is to promote the discovery of novel taxa and explore the ascomycete diversity in the region, utilising a morphology-phylogeny approach. This article represents the second series of species descriptions for the project and introduces three undocumented species found in the families Bambusicolaceae, Dictyosporiaceae and Periconiaceae, belonging to the suborder Massarineae (Pleosporales, Dothideomycetes). These novel taxa exhibit typical morphological characteristics of Bambusicola, Periconia and Trichobotrys, leading to their designation as Bambusicolahongheensis, Periconiakunmingensis and Trichobotryssinensis. Comprehensive multigene phylogenetic analyses were conducted to validate the novelty of these species. The results revealed well-defined clades that are clearly distinct from other related species, providing robust support for their placement within their respective families. Notably, this study unveils the phylogenetic affinity of Trichobotrys within Dictyosporiaceae for the first time. Additionally, the synanamorphism for the genus Trichobotrys is also reported for the first time. Detailed descriptions, illustrations and updated phylogenies of the novel species are provided, and thus presenting a valuable resource for researchers and mycologists interested in the diversity of ascomycetes in Yunnan. By enhancing our understanding of the Ascomycota diversity in this region, this research contributes to the broader field of fungal taxonomy and their phylogenetic understanding.

Heart Rot Disease of Walnut Caused by Nothophoma juglandis sp. nov. and Its Endophytic Biocontrol Agent

English walnut (Juglans regia L.) is an economically important hardwood tree species cultivated worldwide. Walnut heart rot disease leading to heartwood decay of trees has been frequently observed in a number of plantations in China. To identify the causal agent, 29 diseased stem samples were collected from walnut plantations in Beijing, and 54 fungal isolates were obtained. Koch's postulates were developed, and the results showed that Nothophoma juglandis, a species new to science, was the causal agent of walnut heart rot disease. Granulobasidium vellereum, a notable biocontrol agent, was coisolated with N. juglandis. An antagonistic assay on dual culture and walnut stems (both in the field and detached branches) proved that G. vellereum acted as a potential biocontrol agent against N. juglandis, as it could significantly inhibit the expansion of N. juglandis. The optimal temperature for mycelial growth and pathogenicity of N. juglandis was 26.6 and 27.0°C, respectively, which frequently occur in the summer of the walnut-growing regions in China.

Microbiome structure variation and soybean's defense responses during flooding stress and elevated CO2

Introduction

With current trends in global climate change, both flooding episodes and higher levels of CO2 have been key factors to impact plant growth and stress tolerance. Very little is known about how both factors can influence the microbiome diversity and function, especially in tolerant soybean cultivars. This work aims to (i) elucidate the impact of flooding stress and increased levels of CO2 on the plant defenses and (ii) understand the microbiome diversity during flooding stress and elevated CO2 (eCO2).

Methods

We used next-generation sequencing and bioinformatic methods to show the impact of natural flooding and eCO2 on the microbiome architecture of soybean plants' below- (soil) and above-ground organs (root and shoot). We used high throughput rhizospheric extra-cellular enzymes and molecular analysis of plant defense-related genes to understand microbial diversity in plant responses during eCO2 and flooding.

Results

Results revealed that bacterial and fungal diversity was substantially higher in combined flooding and eCO2 treatments than in non-flooding control. Microbial diversity was soil>root>shoot in response to flooding and eCO2. We found that sole treatment of eCO2 and flooding had significant abundances of Chitinophaga, Clostridium, and Bacillus. Whereas the combination of flooding and eCO2 conditions showed a significant abundance of Trichoderma and Gibberella. Rhizospheric extra-cellular enzyme activities were significantly higher in eCO2 than flooding or its combination with eCO2. Plant defense responses were significantly regulated by the oxidative stress enzyme activities and gene expression of Elongation factor 1 and Alcohol dehydrogenase 2 in floodings and eCO2 treatments in soybean plant root or shoot parts.

Conclusion

This work suggests that climatic-induced changes in eCO2 and submergence can reshape microbiome structure and host defenses, essential in plant breeding and developing stress-tolerant crops. This work can help in identifying core-microbiome species that are unique to flooding stress environments and increasing eCO2.

Morphological and Phylogenetic Analyses Reveal Three New Species of Didymella (Didymellaceae, Pleosporales) from Jiangxi, China

Didymella contains numerous plant pathogenic and saprobic species associated with a wide range of hosts. Over the course of our mycological surveys of plant pathogens from terrestrial plants in Jiangxi Province, China, eight strains isolated from diseased leaves of four host genera represented three new species of Didymella, D. bischofiae sp. nov., D. clerodendri sp. nov., and D. pittospori sp. nov. Phylogenetic analyses of combined ITS, LSU, RPB2, and TUB2 sequence data, using maximum-likelihood (ML) and Bayesian inference (BI), revealed their taxonomic placement within Didymella. Both morphological examinations and molecular phylogenetic analyses supported D. bischofiae, D. clerodendri, and D. pittospori as three new taxa within Didymella. Illustrations and descriptions of these three taxa were provided, along with comparisons with closely related taxa in the genus.

Didymella gigantis sp. nov. Causing Leaf Spot in Korean Angelica

During a disease survey in October 2019, leaf spot symptoms with a yellow halo were observed on Korean angelica (Anglica gigas) plants grown in fields in Pyeongchang, Gangwon Province, Korea. Incidence of diseased leaves of the plants in the investigated fields ranged from 10% to 60%. Morphological and cultural characteristics of two single-spore isolates from the leaf lesions indicated that they belonged to the genus Didymella. Molecular phylogenetic analyses using combined sequences of LSU, ITS, TUB2, and RPB2 regions showed distinct clustering of the isolates from other Didymella species. In addition, the morphological and cultural characteristics of the isolates were somewhat different from those of closely related Didymella spp. Therefore, the novelty of the isolates was proved based on the investigations. Pathogenicity of the novel Didymella species isolates was confirmed on leaves of Korean angelica plants via artificial inoculation. This study reveals that Didymella gigantis sp. nov. causes leaf spot in Korean angelica.

The Identity, Virulence, and Antifungal Effects of the Didymellacesous Fungi Associated with the Rapeseed Blackleg Pathogen Leptosphaeria biglobosa

Eight fungal strains (P1 to P8) were isolated from rapeseed stems (Brassica napus) infected with the blackleg pathogen Leptosphaeria biglobosa (Lb). They formed pycnidia with similar morphology to those of Lb, and thus were considered as Lb relatives (LbRs). The species-level identification of these strains was performed. Their virulence on rapeseed and efficacy in the suppression of Lb infection were determined, and the biocontrol potential and biocontrol mechanisms of strain P2 were investigated. The results showed that the LbRs belong to two teleomorphic genera in the family Didymellaceae, Didymella for P1 to P7 and Boeremia for P8. Pathogenicity tests on rapeseed cotyledons and stems indicated the LbRs were weakly virulent compared to L. biglobosa. Co-inoculation assays on rapeseed cotyledons demonstrated that P1 to P7 (especially P1 to P4) had a suppressive effect on Lb infection, whereas P8 had a marginal effect on infection by L. biglobosa. Moreover, D. macrostoma P2 displayed a more aggressive behavior than L. biglobosa in the endophytic colonization of healthy rapeseed cotyledons. Cultures of P2 in potato dextrose broth (PDB) and pycnidiospore mucilages exuded from P2 pycnidia showed antifungal activity to L. biglobosa. Further leaf assays revealed that antifungal metabolites (AM) of strain P2 from PDB cultures effectively suppressed infection by L. biglobosa, Botrytis cinerea (gray mold), and Sclerotinia sclerotiorum (white mold). An antifungal metabolite, namely penicillither, was purified and identified from PDB cultures and detected in pycnidiospore mucilages of strain P2. This study suggests that the LbRs are a repertoire for screening biocontrol agents (BCAs) against rapeseed diseases, and D. macrostoma P2 is a multi-functional BCA, a penicillither producer, and an endophyte.

A novel species of Microsphaeropsis causing cankers on Rafnia amplexicaulis in South Africa

Cankers leading to branch, stem and plant death were observed on the South African endemic Rafnia amplexicaulis (Fabaceae) in the Cederberg Wilderness Area, South Africa, during September 2021. Conidiomatal pycnidia were found developing on the cankers, and isolations consistently yielded a Microsphaeropsis species. Phylogenetic analysis based on partial nucleotide sequences of the internal transcribed spacers (ITS), the nuclear large subunit (LSU) and RNA polymerase II second largest subunit (RPB2) regions showed that the fungus represented an undescribed species. Based on the multigene phylogeny and morphological characteristics, we describe the species here as M. rafniae sp. nov. Pathogenicity tests and the fulfilment of Koch's postulates confirmed that M. rafniae sp. nov. is the cause of the cankers of R. amplexicaulis. Presently, this disease is known from a single location in South Africa, and further surveys are required to determine its distribution and relative importance. Citation: Paap T, Marincowitz S, Pham NQ, Roets F, Basson RJ, Wingfield BD, Oberlander K, Wingfield MJ (2023). A novel species of Microsphaeropsis causing cankers on Rafnia amplexicaulis in South Africa. Fungal Systematics and Evolution 12: 73-80. doi: 10.3114/fuse.2023.12.05.

Didymella acutilobae sp. nov. Causing Leaf Spot and Stem Rot in Angelica acutiloba

During disease surveys of Angelica acutiloba plants in Korea, leaf spot symptoms were observed in a field in Andong in July 2019, and stem rot symptoms in vinyl greenhouses in Yangpyeong in April 2020. Incidence of leaf spot and stem rot of the plants ranged from 10 to 20% and 5 to 30%, respectively. Morphological and cultural characteristics of fungal isolates from the leaf spot and stem rot symptoms fitted into those of the genus Phoma. Molecular phylogenetic analyses of two single-spore isolates from the symptoms using concatenated sequences of LSU, ITS, TUB2, and RPB2 genes authenticated an independent cluster from other Didymella (anamorph: Phoma) species. Moreover, the isolates showed different morphological and cultural characteristics in comparison to closely related Didymella species. These discoveries confirmed the novelty of the isolates. Pathogenicity of the novel Didymella species isolates was substantiated on leaves and stems of A. acutiloba through artificial inoculation. Thus, this study reveals that Didymella acutilobae sp. nov. causes leaf spot and stem rot in Angelica acutiloba.

Sequencing, Functional Annotation, and Interaction Prediction of mRNAs and Candidate Long Noncoding RNAs Originating from Tea Leaves During Infection by the Fungal Pathogen Causing Tea Leaf Spot, Didymella bellidis

Tea leaf spot caused by Didymella bellidis can seriously reduce the productivity and quality of tea (Camellia sinensis var. sinensis) leaves in Guizhou Province, southwest China. Analysis of the relationship between messenger RNAs (mRNAs) and long non-coding RNAs (lncRNAs) of tea could provide insights into the plant-pathogen interaction. In this study, high-throughput sequencing of mRNAs and lncRNAs from tea leaves during infection by D. bellidis was conducted using the Illumina Novaseq 6000 platform. Infection by D. bellidis hyphae resulted in up- or downregulation of 553 and 191 of the differentially expressed mRNAs (DEmRNAs), respectively. As the S gene number (total number of genes with significantly differential expression annotated in the specified Gene Ontology [GO] database), three were enriched with respect to the defense response to the fungus at the biological process level. Expression of the DEmRNAs peroxidase 21 (TEA000222.1) and mcht-2 (TEA013240.1) originating from tea leaves were upregulated during challenge by D. bellidis hyphae, whereas expression of the LRR receptor-like serine/threonine-protein kinase ERECTA (TEA016781.1) gene was downregulated. The infection of D. bellidis hyphae resulted in up- or downregulation of 227 and 958 of the differentially expressed lncRNAs (DElncRNAs). The DEmRNAs associated with uncharacterized LOC101499401 (TEA015626.1), uncharacterized protein (TEA014125.1), structural maintenance of chromosomes protein 1 (TEA001660.1), and uncharacterized protein (TEA017727.1) occurred as a result of cis regulation by DElncRNAs MSTRG.20036, MSTRG.3843, MSTRG.26132, and MSTRG.56701, respectively. The expression profiling and lncRNA/mRNA association prediction in the tea leaves infected by D. bellidis will provide a valuable resource for further research into disease resistance.

Composition of the alfalfa pathobiome in commercial fields

Through the recent advances of modern high-throughput sequencing technologies, the "one microbe, one disease" dogma is being gradually replaced with the principle of the "pathobiome". Pathobiome is a comprehensive biotic environment that not only includes a diverse community of all disease-causing organisms within the plant but also defines their mutual interactions and resultant effect on plant health. To date, the concept of pathobiome as a major component in plant health and sustainable production of alfalfa (Medicago sativa L.), the most extensively cultivated forage legume in the world, is non-existent. Here, we approached this subject by characterizing the biodiversity of the alfalfa pathobiome using high-throughput sequencing technology. Our metagenomic study revealed a remarkable abundance of different pathogenic communities associated with alfalfa in the natural ecosystem. Profiling the alfalfa pathobiome is a starting point to assess known and identify new and emerging stress challenges in the context of plant disease management. In addition, it allows us to address the complexity of microbial interactions within the plant host and their impact on the development and evolution of pathogenesis.

New Species of Didymellaceae within Aquatic Plants from Southwestern China

Members of Didymellaceae have a wide geographical distribution throughout different ecosystems, and most species are associated with fruit, leaf, stem and root diseases of land plants. However, species that occur in aquatic plants are not clearly known. During a survey of the diversity of endophytes in aquatic plants in Yunnan, Sichuan, and Guizhou provinces, we obtained 51 isolates belonging to Didymellaceae based on internal transcribed spacer region (ITS) sequences. Further, the phylogenetic positions of these isolates were determined by combined sequences composed of ITS, partial large subunit nrRNA gene (28S nrDNA; LSU), RNA polymerase II second largest subunit (rpb2) and partial beta-tubulin gene (tub2). Combining morphological characteristics and multi-locus phylogenetic analyses, two new varieties belong to Boeremia and 12 new species distributed into seven genera were recognized from 51 isolates, i.e., Cumuliphoma, Didymella, Dimorphoma, Ectophoma, Leptosphaerulina, Remotididymella, and Stagonosporopsis. Among these species, only one species of Stagonosporopsis and two species of Leptosphaerulina show teleomorphic stages on OA, but have no anamorphic state. Each new species is described in detail, and the differences between new species and their phylogenetically related species are discussed here. The high frequency of new species indicates that aquatic plants may be a special ecological niche which highly promotes species differentiation. At the same time, the frequent occurrence of new species may indicate the need for extensive investigation of fungal resources in those aquatic environments where fungal diversity may be underestimated.

Genomic and Transcriptomic Survey Provides Insights into Molecular Basis of Pathogenicity of the Sunflower Pathogen Phoma macdonaldii

Phoma macdonaldii (teleomorph Leptosphaeria lindquistii) is the causal agent of sunflower (Helianthus annuus L.) black stem. In order to investigate the molecular basis for the pathogenicity of P. ormacdonaldii, genomic and transcriptomic analyses were performed. The genome size was 38.24 Mb and assembled into 27 contigs with 11,094 putative predicted genes. These include 1133 genes for CAZymes specific for plant polysaccharide degradation, 2356 for the interaction between the pathogen and host, 2167 for virulence factors, and 37 secondary metabolites gene clusters. RNA-seq analysis was conducted at the early and late stages of the fungal spot formation in infected sunflower tissues. A total of 2506, 3035, and 2660 differentially expressed genes (DEGs) between CT and each treatment group (LEAF-2d, LEAF-6d, and STEM) were retrieved, respectively. The most significant pathways of DEGs from these diseased sunflower tissues were the metabolic pathways and biosynthesis of secondary metabolites. Overall, 371 up-regulated DEGs were shared among LEAF-2d, LEAF-6d, and STEM, including 82 mapped to DFVF, 63 mapped to PHI-base, 69 annotated as CAZymes, 33 annotated as transporters, 91 annotated as secretory proteins, and a carbon skeleton biosynthetic gene. The most important DEGs were further confirmed by RT-qPCR. This is the first report on the genome-scale assembly and annotation for P. macdonaldii. Our data provide a framework for further revealing the underlying mechanism of the pathogenesis of P. macdonaldii, and also suggest the potential targets for the diseases caused by this fungal pathogen.

Identification and pathogenicity analysis of leaf brown spot of Juglans regia in China

English walnut (Juglans regia), has high economic and ecological value. As an important tree species for eliminating poverty, it is planted in many Provinces of China. In 2021, new pathogenic fungi were observed in English walnut in Guangyuan City, Sichuan Province, China. The initial symptom of leaf infection is that the leaves are covered with small black spots, which gradually expand into larger brown spots. Most of the spots appeared at the edges of the leaves, and yellow whorls were observed at the junction between the spots and the healthy leaves. The pathogenic fungi were isoalted form collecting disease samples and purified by single-spore culturing. In vitro and field experiments showed that the pathogen could cause brown spots on walnut leaves. The inoculation experiment showed that the symptoms in the field experiment were the same as those observed on the spot; however, slight differences were observed in the in vitro experiment. Ten isolates were obtained from walnut leaves with brown spot symptoms, and these were further characterized based on morphology and DNA sequencing. ITS (internal transcribed spacer), LSU (large sub-unit rDNA), rpb2 (second largest subunit of RNA polymerase) and tub2 (beta-tubulin) gene regions were used to construct phylogenetic trees and determine the evolutionary relationships among the collected strains. The isolate was identified as Nothophoma quercina by morphological and polygene analyses. As far as we are aware, the brown spots on walnut leaves caused by N. quercina is the first report of its kind.

Characterization and Control of Dendrobium officinale Bud Blight Disease

Dendrobium officinale is an important traditional Chinese medicine (TCM). A disease causing bud blight in D. officinale appeared in 2021 in Yueqing city, Zhejiang Province, China. In this paper, 127 isolates were obtained from 61 plants. The isolates were grouped into 13 groups based on collected areas and morphological observations. Four loci (ITS, LSU, tub2 and rpb2) of 13 representative isolates were sequenced and the isolates were identified by constructing phylogenetic trees with the multi-locus sequence analysis (MLSA) method. We found the disease to be associated with three strains: Ectophoma multirostrata, Alternaria arborescens and Stagonosporopsis pogostemonis, with isolates frequencies of 71.6%, 21.3% and 7.1%, respectively. All three strains are pathogenic to D. officinale. A. arborescens and S. pogostemonis isolated from D. officinale were reported for the first time. Iprodione (50%), 33.5% oxine-copper and Meitian (containing 75 g/L pydiflumetofen and 125 g/L difenoconazole) were chosen to control the dominant pathogen E. multirostrata, with an EC₅₀ value of 2.10, 1.78 and 0.09 mg/L, respectively. All three fungicides exhibited an effective inhibition of activities to the growth of the dominant pathogen E. multirostrata on potato dextrose agar (PDA) plates, with Meitian showing the strongest inhibitory effect. We further found that Meitian can effectively control D. officinale bud blight disease in pot trial.

Intraspecific Comparative Analysis Reveals Genomic Variation of Didymella arachidicola and Pathogenicity Factors Potentially Related to Lesion Phenotype

Didymella arachidicola is one of the most important fungal pathogens, causing foliar disease and leading to severe yield losses of peanuts (Arachis hypogaea L.) in China. Two main lesion phenotypes of peanut web blotch have been identified as reticulation type (R type) and blotch type (B type). As no satisfactory reference genome is available, the genomic variations and pathogenicity factors of D. arachidicola remain to be revealed. In the present study, we collected 41 D. arachidicola isolates from 26 geographic locations across China (33 for R type and 8 for B type). The chromosome-scale genome of the most virulent isolate (YY187) was assembled as a reference using PacBio and Hi-C technologies. In addition, we re-sequenced 40 isolates from different sampling sites. Genome-wide alignments showed high similarity among the genomic sequences from the 40 isolates, with an average mapping rate of 97.38%. An average of 3242 SNPs and 315 InDels were identified in the genomic variation analysis, which revealed an intraspecific polymorphism in D. arachidicola. The comparative analysis of the most and least virulent isolates generated an integrated gene set containing 512 differential genes. Moreover, 225 genes individually or simultaneously harbored hits in CAZy-base, PHI-base, DFVF, etc. Compared with the R type reference, the differential gene sets from all B type isolates identified 13 shared genes potentially related to lesion phenotype. Our results reveal the intraspecific genomic variation of D. arachidicola isolates and pathogenicity factors potentially related to different lesion phenotypes. This work sets a genomic foundation for understanding the mechanisms behind genomic diversity driving different pathogenic phenotypes of D. arachidicola.

Two Novel Species of Mesophoma gen. nov. from China

During an investigation of the fungal pathogens associated with the invasive weed Ageratina adenophora from China, some interesting isolates were obtained from healthy leaf, leaf spot, and roots of this weed. Among them, a novel genus Mesophoma, containing two novel species M. speciosa and M. ageratinae, was found. Phylogenetic analysis of the combined, the internal transcribed spacer (ITS), large nuclear subunit ribosomal DNA (LSU), the RNA polymerase II second largest subunit (rpb2), and the partial β-tubulin (tub2) sequences, showed that M. speciosa and M. ageratinae formed a distinct clade far from all genera previously described in the family Didymellaceae. Combined distinctive morphological characters, including smaller and aseptate conidia when comparing with nearby genera Stagonosporopsis, Boeremia, and Heterphoma, allowed us to describe them as novel species belonging to a novel genus Mesophoma. The full descriptions, illustrations, and a phylogenetic tree showing the position of both M. speciosa and M. ageratinae are provided in this paper. Moreover, the potential for two strains belonging to these two species to be developed into a biocontrol for the spread of the invasive weed Ag. adenophora is also discussed.

Characteristics of Leaf Spot Disease Caused by Didymella Species and the Influence of Infection on Tea Quality

Leaf spots are the most damaging and common foliar diseases of tea and are caused by several species of fungi. During 2018 to 2020, leaf spot diseases showing different symptoms (large and small spots) were observed in commercial tea plantations in Guizhou and Sichuan provinces of China. The pathogen causing the two different sized leaf spots was identified as the same species (Didymella segeticola) based on morphological characteristics, pathogenicity, and multilocus phylogenetic analysis using the combined ITS, TUB, LSU, and RPB2 gene regions. Microbial diversity analysis of lesion tissues from small spots on naturally infected tea leaves further confirmed Didymella to be present as the main pathogen. Results of sensory evaluation and quality-related metabolite analysis of tea shoots infected with the small leaf spot symptom indicated that D. segeticola negatively affected the quality and flavor of tea by changing the composition and content of caffeine, catechins, and amino acids. In addition, the significantly reduced amino acid derivatives in tea are confirmed to be positively associated with the enhanced bitter taste. The results improve our understanding of the pathogenicity of Didymella species and the influence of Didymella on the host plant, Camellia sinensis.

Diversity and Pathogenicity of Fungi Associated with Fruit Rot of Winter Jujube in Shandong Province, China

Winter jujube originated from China and had an extremely high nutritional value. In 2021, symptomatic winter jujube fruits were collected from eight locations in Zhanhua District of Binzhou City, Shandong Province. In total, 108 fungal isolates were obtained and grouped into 11 species based on morphological characteristics and multilocus phylogenetic analysis, including Nothophoma quercina (43.52%), Fusarium lateritium (20.37%), Alternaria alternata (12.03%), F. proliferatum (7.41%), F. graminearum (4.63%), Botryosphaeria dothidea (3.70%), Fusarium sp. (2.78%), A. tenuissima (2.78%), Diaporthe eres (1.85%), Nigrospora oryzae (0.93%), and Cercospora nicotianae (0.93%). All fungal isolates obtained in this study showed aggressiveness on detached winter jujube fruits except N. oryzae and C. nicotianae isolates, of which F. proliferatum was the most virulent, while A. alternata isolates, which have been considered the major pathogen of winter jujube fruit rot, showed a relatively low-level virulence in this study. Furthermore, D. eres, F. graminearum, F. lateritium, and an unclassified Fusarium species were first reported as causal agents of winter jujube fruit rot. The typical symptoms of winter jujube fruit rot observed in this study could be distinguished into two types. N. quercina, A. alternata, A. tenuissima, Fusarium sp., D. nobilis, and F. lateritium isolates caused reddish brown to dark gray lesions on the peel, while B. dothidea, F. graminearum, and F. proliferatum isolates caused peel and pulp decay, resulting in red to reddish brown and water-soaked lesions. In addition, haplotype analysis of N. quercina isolates obtained in this study and validly published articles showed that there were 11 haplotypes worldwide; the isolates obtained in the current study were grouped into three haplotypes (Hap 1, Hap 2, and Hap 11), and two of them (Hap 2 and Hap 11) were confirmed as new haplotypes.

First Report of Nothophoma quercina Causing Brown Spot Disease on 'Huanghua' Pear (Pyrus pyrifolia Nakai) in China

Pear (Pyrus L.) is an important fruit tree in China, which has the largest cultivation area and yield in the world (Jia et al. 2021). In June 2022, brown spot symptoms were observed on 'Huanghua' pear (Pyrus pyrifolia Nakai, cv. Huanghua) leaves in the germplasm garden of Anhui Agricultural University (High Tech Agricultural Garden), Anhui, Hefei, China. The disease incidence was approximately 40% according to the percentage of diseased leaves among 300 leaves (50 leaves each were obtained from 6 plants). Initially, small, brown, round to oval lesions appeared on the leaves, the spots were gray in the central, and surrounded by brown to black margins. These spots rapidly enlarged, eventually causing abnormal leaf defoliation. To isolate the brown spot pathogen, symptomatic leaves were harvested, washed with sterile water, surface-sterilized with 75% ethanol for 20 s, and washed 3-4 times with sterile water. Leaf fragments were placed onto PDA medium and incubated at 25°C for 7 days to obtain isolates. The colonies exhibited white to pale gray aerial mycelium and reached a diameter of 62 mm after 7 days of incubation. Conidiogenous cells were characterized as phialides, and exhibited a doliform to ampulliform shape. Conidia displayed various shapes and sizes, ranging from subglobose to oval or obtuse, with thin walls, aseptate hyphae, and a smooth surface. They measured 4.2-7.9 × 3.1-5.5 μm in diameter. These morphologies were similar to Nothophoma quercina as reported previously (Bai et al. 2016; Kazerooni et al. 2021). For molecular analysis, the internal transcribed spacers (ITS), beta-tubulin (TUB2), and actin (ACT) regions were amplified using the primers ITS1/ITS4, Bt2a/Bt2b, and ACT-512F/ACT-783R respectively. The sequences of ITS, TUB2, and ACT were deposited in GenBank (accession numbers: OP554217, OP595395, and OP595396, respectively). A nucleotide blast search revealed high homology with N. quercina sequences: MH635156 (ITS: 541/541, 100%), MW672036.1 (TUB2: 343/346, 99%), FJ426914.1 (ACT: 242/262, 92%). A phylogenetic tree was constructed with ITS, TUB2 and ACT sequences based on neighbor-joining method using MEGA-X software, which showed the highest similarity with N. quercina. To confirm the pathogenicity, the leaves of three healthy plants were sprayed with spore suspension (106 conidia/mL), whereas control leaves were prayed with sterile water. The inoculated plants were covered with plastic bags and cultured in a growth chamber (90% relative humidity) at 25°C. Typical disease symptoms appeared on the inoculated leaves after 7-10 days, whereas no symptoms were observed on the control leaves. The same pathogen was re-isolated from the diseased leaves, according with Koch's postulates. Therefore, based on morphological and phylogenetic tree analyses, we confirmed that the causal organism for brown spot disease was N. quercina fungus (Chen et al. 2015; Jiao et al. 2017). To our knowledge, this is the first report of brown spot disease caused by N. quercina on 'Huanghua' pear leaves in China.

Soil Fungal Diversity and Ecology Assessed Using DNA Metabarcoding along a Deglaciated Chronosequence at Clearwater Mesa, James Ross Island, Antarctic Peninsula

We studied the fungal diversity present in soils sampled along a deglaciated chronosequence from para- to periglacial conditions on James Ross Island, north-east Antarctic Peninsula, using DNA metabarcoding. A total of 88 amplicon sequence variants (ASVs) were detected, dominated by the phyla Ascomycota, Basidiomycota and Mortierellomycota. The uncommon phyla Chytridiomycota, Rozellomycota, Monoblepharomycota, Zoopagomycota and Basidiobolomycota were detected. Unknown fungi identified at higher hierarchical taxonomic levels (Fungal sp. 1, Fungal sp. 2, Spizellomycetales sp. and Rozellomycotina sp.) and taxa identified at generic and specific levels (Mortierella sp., Pseudogymnoascus sp., Mortierella alpina, M. turficola, Neoascochyta paspali, Penicillium sp. and Betamyces sp.) dominated the assemblages. In general, the assemblages displayed high diversity and richness, and moderate dominance. Only 12 of the fungal ASVs were detected in all chronosequence soils sampled. Sequences representing saprophytic, pathogenic and symbiotic fungi were detected. Based on the sequence diversity obtained, Clearwater Mesa soils contain a complex fungal community, including the presence of fungal groups generally considered rare in Antarctica, with dominant taxa recognized as cold-adapted cosmopolitan, endemic, saprotrophic and phytopathogenic fungi. Clearwater Mesa ecosystems are impacted by the effects of regional climatic changes, and may provide a natural observatory to understand climate change effects over time.

Plant-Associated Novel Didymellaceous Taxa in the South China Botanical Garden (Guangzhou, China)

The South China Botanical Garden (SCBG), one of the largest and oldest botanical gardens in China, conserves important plant germplasms of endangered species. Therefore, ensuring tree health and studying the associated mycobiome of the phyllosphere is essential to maintaining its visual aesthetics. During a survey of plant-associated microfungal species in SCBG, we collected several coelomycetous taxa. Phylogenetic relationships were evaluated based on the analyses of ITS, LSU, RPB2, and β-tubulin loci. The morphological features of the new collections were compared with those of existing species, emphasizing close phylogenetic affinities. Based on the morphological comparisons and multi-locus phylogeny, we introduce three new species. These are Ectophoma phoenicis sp. nov., Remotididymella fici-microcarpae sp. nov., and Stagonosporopsis pedicularis-striatae sp. nov. In addition, we describe a new host record for Allophoma tropica in the Didymellaceae. Detailed descriptions and illustrations are provided along with notes comparing allied species.

Farming system effects on root rot pathogen complex and yield of faba bean (vicia faba) in Germany

A survey across Germany was undertaken from 2016-2019 to evaluate effects of management system (organic vs conventional), pedo-climatic conditions and crop rotation history on faba bean root health status, diversity of major root rot pathogens and yield. Root rot incidence was generally low and there was no effect of the management system on the spectrum of pathogens isolated. Among the most common fungal species identified, frequencies of Fusarium redolens and Didymella pinodella were significantly higher in roots from organic fields compared with conventional and lower was observed for F. avenaceum, F. tricinctum and F. culmorum. Faba bean roots were colonized at similar rates by F. equiseti and the members of the F. oxysporum (FOSC) and F. solani (FSSC) species complexes in both management systems. Almost no legumes had been grown in the 5-11 years preceding the conventional faba beans surveyed while legumes had almost always been present during this period in the organic fields. This difference in rotational histories between the farming systems led to apparent cropping systems effects on the isolation frequencies of several species. For example, D. pinodella was ubiquitous in organic fields with a high frequency of legumes in the rotations but much rarer and often absent in conventional fields. Pedo-climatic conditions, particularly cool conditions at sowing and plant emergence and/or during the vegetative season favored most of the most prevalent Fusarium species identified in this study. In organic systems, yields correlated negatively with D. pinodella and F. redolens frequencies whereas higher levels of F. tricintum in faba bean roots had a positive correlation with yield. In conventional systems, faba bean yields depended more on the total precipitation before sowing and during the main growing season but were also negatively correlated with the frequencies of FOSC and F. culmorum. Phylogenetic analysis based on the TEF1 alpha locus indicated that the FSSC isolates mainly belonged to the F. pisi lineage. In contrast, the FOSC isolates were placed in 9 different lineages, with a conspicuous dominance of F. libertatis that has until now not been associated with any leguminous host.

Diversity of Endophytic Fungi in Annual Shoots of Prunus mandshurica (Rosaceae) in the South of Amur Region, Russia

Prunus mandshurica is a rare species of the Russian Far East; it is cultivated for fruits and as an ornamental tree. The objective was to determine the fungi associated with young shoots of the Manchurian apricot, which is an important biotic factor for plant viability and productivity. Fungi were isolated by incubation of shoot fragments (unsterilized or surface-sterilized) on a growth medium and identified according to their cultural and morphological characteristics. Diaporthe eres and Nothophoma quercina isolates were identified by multilocus phylogenetic analysis (apn2, cal, tef1-α, tub2 for D. eres, and ITS, rpb2, tub2 for N. quercina). In total, 12 species (Alternaria alternata, A. tenuissima, Aureobasidium pullulans, Cladosporium cladosporioides, C. herbarum, D. eres, Epicoccum nigrum, Fusarium graminearum, F. oxysporum, N. quercina, Sarocladium strictum, and Tripospermum myrti) and one genus (Gliocladium sp.) were found. Alternaria alternata, N. quercina, and D. eres were the most frequent species of the shoots. Alternaria tenuissima and F. oxysporum were also frequent in some collections, while all other species were rare or occasional in occurrence. Molecular analysis of D. eres and N. quercina revealed redundancy of some species within the D. eres species complex and the genus Nothophoma. This is the first report on the fungal inhabitants of asymptomatic shoots of P. mandshurica. Nothophoma quercina was identified in Russia for the first time.

Epicoccum spp. Causing Maize Leaf Spot in Heilongjiang Province, China

Maize leaf spot occurs worldwide and affects maize production. Maize can be infected by several pathogens causing leaf spot, such as Bipolaris zeicola, Bipolaris maydis, Curvularia species, Alternaria species, etc. In the current study, 30 Epicoccum isolates recovered from symptomatic maize leaves were identified based on morphological characteristics, pathogenicity, and multilocus sequence analyses of nuLSU, ITS, tub2, and rpb2. These maize isolates were grouped into five Epicoccum species, including E. nigrum, E. layuense, E. sorghinum, E. latusicollum, and E. pneumoniae. Pathogenicity tests showed that all five Epicoccum species could produce small ellipse- and spindle-shaped spots on maize leaves. The lesion center was grayish yellow to dark gray and surrounded by a chlorotic area. Furthermore, the Epicoccum isolates exhibited high pathogenicity to 20 main maize varieties of Heilongjiang Province but showed different sensitivities to the commonly used fungicides carbendazim and tebuconazole. In addition, these Epicoccum isolates showed different production capacity of pectinase, cellulase, protease, amylase, laccase, and gelatinase, but all showed high lipase activity. This is the first report globally of E. layuense, E. latusicollum, and E. pneumoniae as causal agents of maize leaf spot. E. pneumoniae was first reported as a plant pathogen.

New and Interesting Fungi. 5

Nine new genera, 17 new species, nine new combinations, seven epitypes, three lectotypes, one neotype, and 14 interesting new host and / or geographical records are introduced in this study. New genera: Neobarrmaelia (based on Neobarrmaelia hyphaenes), Neobryochiton (based on Neobryochiton narthecii), Neocamarographium (based on Neocamarographium carpini), Nothocladosporium (based on Nothocladosporium syzygii), Nothopseudocercospora (based on Nothopseudocercospora dictamni), Paracamarographium (based on Paracamarographium koreanum), Pseudohormonema (based on Pseudohormonema sordidus), Quasiphoma (based on Quasiphoma hyphaenes), Rapidomyces (based on Rapidomyces narthecii). New species: Ascocorticium sorbicola (on leaves of Sorbus aucuparia, Belgium), Dactylaria retrophylli (on leaves of Retrophyllum rospigliosii, Colombia), Dactylellina miltoniae (on twigs of Miltonia clowesii, Colombia), Exophiala eucalyptigena (on dead leaves of Eucalyptus viminalis subsp. viminalis supporting Idolothrips spectrum, Australia), Idriellomyces syzygii (on leaves of Syzygium chordatum, South Africa), Microcera lichenicola (on Parmelia sulcata, Netherlands), Neobarrmaelia hyphaenes (on leaves of Hyphaene sp., South Africa), Neobryochiton narthecii (on dead leaves of Narthecium ossifragum, Netherlands), Niesslia pseudoexilis (on dead leaf of Quercus petraea, Serbia), Nothocladosporium syzygii (on leaves of Syzygium chordatum, South Africa), Nothotrimmatostroma corymbiae (on leaves of Corymbia henryi, South Africa), Phaeosphaeria hyphaenes (on leaves of Hyphaene sp., South Africa), Pseudohormonema sordidus (on a from human pacemaker, USA), Quasiphoma hyphaenes (on leaves of Hyphaene sp., South Africa), Rapidomyces narthecii (on dead leaves of Narthecium ossifragum, Netherlands), Reticulascus parahennebertii (on dead culm of Juncus inflexus, Netherlands), Scytalidium philadelphianum (from compressed air in a factory, USA). New combinations: Neobarrmaelia serenoae, Nothopseudocercospora dictamni, Dothiora viticola, Floricola sulcata, Neocamarographium carpini, Paracamarographium koreanum, Rhexocercosporidium bellocense, Russula lilacina. Epitypes: Elsinoe corni (on leaves of Cornus florida, USA), Leptopeltis litigiosa (on dead leaf fronds of Pteridium aquilinum, Netherlands), Nothopseudocercospora dictamni (on living leaves of Dictamnus albus, Russia), Ramularia arvensis (on leaves of Potentilla reptans, Netherlands), Rhexocercosporidium bellocense (on leaves of Verbascum sp., Germany), Rhopographus filicinus (on dead leaf fronds of Pteridium aquilinum, Netherlands), Septoria robiniae (on leaves of Robinia pseudoacacia, Belgium). Lectotypes: Leptopeltis litigiosa (on Pteridium aquilinum, France), Rhopographus filicinus (on dead leaf fronds of Pteridium aquilinum, Netherlands), Septoria robiniae (on leaves of Robinia pseudoacacia, Belgium). Neotype: Camarographium stephensii (on dead leaf fronds of Pteridium aquilinum, Netherlands). Citation: Crous PW, Begoude BAD, Boers J, Braun U, Declercq B, Dijksterhuis J, Elliott TF, Garay-Rodriguez GA, Jurjević Ž, Kruse J, Linde CC, Loyd A, Mound L, Osieck ER, Rivera-Vargas LI, Quimbita AM, Rodas CA, Roux J, Schumacher RK, Starink-Willemse M, Thangavel R, Trappe JM, van Iperen AL, Van Steenwinkel C, Wells A, Wingfield MJ, Yilmaz N, Groenewald JZ (2022) New and Interesting Fungi. 5. Fungal Systematics and Evolution 10: 19-90. doi: 10.3114/fuse.2022.10.02.

Impact of the Temperature in Endophytic Ascomycota Isolated from Antarctic Hair-Grass

Antarctica is one of the most inhospitable continents on the planet, with lichens and mosses being the most common terrestrial organisms in ice-free areas. Antarctica is represented by only two species of Angiosperms, Deschampsia antarctica Desv. (Poaceae) and Colobanthus quitensis (Kunth) Bartl. (Caryophyllaceae). In this study, we characterized fungi isolated from the fresh leaves of this grass species. The fungi were isolated from four individual plants from Half Moon Island (246 leaf fragments investigated), and seven from King George Island-Keller Peninsula (with 111 leaf fragments investigated) Antarctica. Neoascochyta paspali, Septoriella elongata, Pyrenophora cf. chaetomioides and Alternaria sp. were associated with the plant and identified through analysis of the sequences of the internal transcribed spacer region (ITS) of the rDNA and nuclear ribosomal large subunit rRNA gene (LSU) as well as through macro and micro-morphological characteristics. The isolates showed higher growth rate ranging from 10 to 20 °C. An interesting result was that the aforementioned fungi are already recognized as both plant pathogens and endophytic fungi. The results demonstrate that D. antarctica is an interesting fungal source. Those species might provide important information about the relationship on the endemic Antarctic biota.

Root rot a silent alfalfa killer in China: Distribution, fungal, and oomycete pathogens, impact of climatic factors and its management

Alfalfa plays a significant role in the pasture ecosystems of China's north, northeast, and northwest regions. It is an excellent forage for livestock, improves soil structure, prevents soil erosion, and has ecological benefits. Presently root rot is a significant threat to the alfalfa productivity because of the survival of the pathogens as soil-borne and because of lack of microbial competition in the impoverished nutrient-deficient soils and resistant cultivars. Furthermore, these regions' extreme ecological and environmental conditions predispose alfalfa to root rot. Moisture and temperature, in particular, have a considerable impact on the severity of root rot. Pathogens such as Fusarium spp. and Rhizoctonia solani are predominant, frequently isolated, and of major concern. These pathogens work together as disease complexes, so finding a host genotype resistant to disease complexes is challenging. Approaches to root rot control in these regions include mostly fungicides treatments and cultural practices and very few reports on the usage of biological control agents. As seed treatment, fungicides such as carbendazim are frequently used to combat root rot; however, resistance to fungicides has arisen. However, breeding and transgenic approaches could be more efficient and sustainable long-term control strategies, especially if resistance to disease complexes may be identified. Yet, research in China is mainly limited to field investigation of root rot and disease resistance evaluation. In this review, we describe climatic conditions of pastoral regions and the role of alfalfa therein and challenges of root rot, the distribution of root rot in the world and China, and the impact of root rot pathogens on alfalfa in particular R. solani and Fusarium spp., effects of environmental factors on root rot and summarize to date disease management approach.

First Report of Leaf Spot Disease Caused by Boeremia linicola on Trifolium repens in China

Trifolium repens L. (White clover) a multipurpose legume crop, primarily utilized as a green manure in China. In March 2018, field investigations showed that a leaf spot disease occurred on T. repens in three fields with 50% to 80% incidence (50 plants in each field were investigated) in Nanchong City, Sichuan Province of China. Infected leaves showed symptoms of irregular dark brown spots in the center of leaves or at the leaf margins. Symptomatic leaves were surface sterilized with 3% NaClO for 3 min followed by 75% ethanol for 30 s and then rinsed in sterile water three times. Thereafter, tissue samples from margins of individual lesions were placed on potato dextrose agar and incubated at 25°C in the dark. Four pure cultures (Y3-1; Y3-2; Y3-3; Y3-4) were obtained by single spore isolation. On oatmeal agar medium, a colony reached 57 mm diameter after 9 d in alternating light and dark at 25℃. Fimbriate aerial hypha were flat and compact with pale brown to dark brown color. Conidiogenous cells were hyaline, smooth, ampulliform to doliiform (n = 30), ranging from 4.1 to 10.5 μm long (6.6 ± 1.8 µm) × 2.2 to 5.7 μm wide (4.1 ± 0.8 µm). Conidia were ellipsoidal to cylindrical, hyaline, thin walled, smooth, aseptate, with 2 to 4 polar guttules (n = 50), ranging from 3.2 to 11.3 μm long (6.3 ± 1.1 µm) × 2.1 to 4.1 μm wide (2.8 ± 0.4 µm). Conidial matrix was whitish. Morphologically these isolates resembled species in Boeremia (Chen et al. 2015). Genomic DNA of each culture was extracted from mycelia using the quick and safe method (Chi et al. 2009). The 28S large subunit of nuclear ribosomal RNA (LSU) region, internal transcribed spacer (ITS) region, RNA polymerase II second largest subunit (RPB2), translation elongation factor 1-α (TEF 1-α), β-Tubulin (TUB2) were amplified with corresponding primers (Carbone and Kohn 1999; Liu et al. 1999; Rehner and Samuels 1994; Sung et al. 2007; Vilgalys and Hester 1990; White et al. 1990; Woudenberg et al.2009). Sequences were deposited in GenBank with accession numbers: ON705759 to ON705766, ON734043 to ON734046 and ON841585 to ON841592. Phylogenetic analysis was conducted with combined sequences of the five loci using the maximum likelihood (ML) and the maximum parsimony (MP) methods. The four isolates and the extype strain of B. linicola (CBS 116.76) clustered together with high bootstrap support (BS) values (MLBS = 100; MPBS = 98). All sequences showed 100% identity to those of CBS 116.76, except the ITS region of our isolates (ON705759 to ON705762), which show 99.6% identity to that of CBS 116.76. Based on morphological characteristics and phylogenetic results, our isolates were identified as B. linicola, although the morphological characteristics of CBS 116.76 had not been characterized. To assess pathogenicity, a conidial suspension (approximately 105 CFU/mL) of isolate Y3-1 was sprayed on 1-month-old healthy plants in a greenhouse at 22℃ to 28℃. Plants sprayed with sterilized water were used as negative controls. The test was conducted three times, each with 3 plants. After 10 days, the leaves of the plants showed irregular brown lesions that were similar to the symptoms observed in the field, control plants remained healthy. The pathogen was reisolated and confirmed to be B. linicola, thus completing the verification of Koch's Postulates. Compared to B. exigua, a causal pathogen associated with leaf spot on white clover reported by Wang et al (Wang et al. 2021), B. linicola produced larger conidia, and the two species did not cluster together in the phylogenetic tree. To our knowledge, this is the first report of leaf spot disease caused by B. linicola on Trifolium repens in China.

Amplicon Sequencing Reveals Novel Fungal Species Responsible for a Controversial Tea Disease

Amplicon sequencing is a powerful tool for analyzing the fungal composition inside plants, whereas its application for the identification of etiology for plant diseases remains undetermined. Here, we utilize this strategy to clarify the etiology responsible for tea leaf brown-black spot disease (LBSD), a noticeable disease infecting tea plants etiology that remains controversial. Based on the ITS-based amplicon sequencing analysis, Didymella species were identified as separate from Pestalotiopsis spp. and Cercospora sp., which are concluded as the etiological agents. This was further confirmed by the fungal isolation and their specific pathogenicity on diverse tea varieties. Based on the morphologies and phylogenetic analysis constructed with multi-loci (ITS, LSU, tub2, and rpb2), two novel Didymella species—tentatively named D. theae and D. theifolia as reference to their host plants—were proposed and characterized. Here, we present an integrated approach of ITS-based amplicon sequencing in combination with fungal isolation and fulfillment of Koch’s postulates for etiological identification of tea plant disease, revealing new etiology for LBSD. This contributes useful information for further etiological identification of plant disease based on amplicon sequencing, as well as understanding, prevention, and management of this economically important disease.

Culturable Endophytic Fungi in Fraxinus excelsior and Their Interactions with Hymenoscyphus fraxineus

The species diversity of culturable endophytic fungi was studied in the leaves and twigs of symptomatic and asymptomatic Fraxinus excelsior trees. Endophytic mycobiota was dominated by Ascomycota species, with Pleosporales (44.17%) and Diaporthales (23.79%) endophytes being the most frequently observed in the tree samples. The number of endophytic isolates and species richness varied depending on the sampling date (May and October) and tissue location. Of the 54 species identified based on ITS sequences, 14 were classified as dominant. The most frequently isolated species were Diaporthe eres, followed by Alternaria alternata, Dothiorella gregaria, and Fraxinicola fraxini. The inhibitory effect of 41 species (75 isolates) of endophytes on the radial growth of a Hymenoscyphus fraxineus isolate was studied under in vitro conditions (dual cultures). The radial growth of H. fraxineus was the most inhibited by four endophytic fungi from twigs (Fusarium lateritium, Didymella aliena, Didymella macrostoma, and Dothiorella gregaria). The inhibitory effect of the four isolates was also studied under in planta conditions. The isolates artificially inoculated into the trunks of ash trees reduced the length of necroses formed by H. fraxineus co-inoculated in the same trunks. This effect depended on the isolate, and the inhibition was most prominent only on trunks inoculated with F. lateritium and D. aliena. Although the total length of necrotic lesions formed by the H. fraxineus infection was shorter in the ash trunks co-inoculated with the endophytes, the difference was not significant.

Morpho-Molecular Characterization of Microfungi Associated with Phyllostachys (Poaceae) in Sichuan, China

In the present study, we surveyed the ascomycetes from bamboo of Phyllostachys across Sichuan Province, China. A biphasic approach based on morphological characteristics and multigene phylogeny confirmed seven species, including one new genus, two new species, and five new host record species. A novel genus Paralloneottiosporina is introduced to accommodate Pa. sichuanensis that was collected from leaves of Phyllostachys violascens. Moreover, the newly introduced species Bifusisporella sichuanensis was isolated from leaves of P. edulis, and five species were newly recorded on bamboos, four species belonging to Apiospora, viz. Ap. yunnana, Ap. neosubglobosa, Ap. jiangxiensis, and Ap. hydei, and the last species, Seriascoma yunnanense, isolated from dead culms of P. heterocycla. Morphologically similar and phylogenetically related taxa were compared. Comprehensive descriptions, color photo plates of micromorphology are provided.

Decontamination and Germination of Buckwheat Grains upon Treatment with Oxygen Plasma Glow and Afterglow

Buckwheat is an alternative crop known for its many beneficial effects on our health. Fungi are an important cause of plant diseases and food spoilage, often posing a threat to humans and animals. This study reports the effects of low-pressure cold plasma treatment on decontamination and germination of common (CB) and Tartary buckwheat (TB) grains. Both plasma glow and afterglow were applied. The glow treatment was more effective in decontamination: initial contamination was reduced to less than 30% in CB and 10% in TB. Fungal diversity was also affected as only a few genera persisted after the glow treatment; however, it also significantly reduced or even ceased the germination capacity of both buckwheat species. Detailed plasma characterisation by optical spectroscopy revealed extensive etching of outer layers as well as cotyledons. Afterglow treatment resulted in a lower reduction of initial fungal contamination (up to 30% in CB and up to 50% in TB) and had less impact on fungal diversity but did not drastically affect germination: 60–75% of grains still germinated even after few minutes of treatment. The vacuum conditions alone did not affect the fungal population or the germination despite an extensive release of water.

Identification of fungi found on desiccated human remains in an arid outdoor environment

Three fungi not previously reported on desiccated human remains were identified on cadavers at the Forensic Investigation Research Station (FIRS) in Whitewater, Colorado. The location of the FIRS provides the unique opportunity to observe the stages of decomposition in a high desert environment. The two cadavers used in the study were in the late stages of decomposition (PMI of approximately 1520 and 1820 days) to the point of desiccation and had developed an extensive black crust on the skin that remained. Skin samples of the two cadavers were taken and plated onto potato dextrose agar to determine whether fungi were present on the desiccated tissues. Three different fungi consistently dominated cultures grown from numerous samples taken from each cadaver. Based on morphological observations, nuclear rDNA sequence data, and phylogenetic analyses, two fungi were identified to species (Aureobasidium melanogenum and Didymella glomerata) and one fungus was identified to the genus level (Alternaria). These results will contribute to the understanding of the role that fungi might play in late-stage decomposition and the extended postmortem period.

Whole genome sequencing and phylogenomic analysis show support for the splitting of genus Pythium

The genus Pythium (nom. cons.) sensu lato (s.l.) is composed of many important species of plant pathogens. Early molecular phylogenetic studies suggested paraphyly of Pythium, which led to a formal proposal by Uzuhashi and colleagues in 2010 to split the genus into Pythium sensu stricto (s.s.), Elongisporangium, Globisporangium, Ovatisporangium (= Phytopythium), and Pilasporangium using morphological characters and phylogenies of the mt cytochrome c oxidase subunit 2 (cox2) and D1-D2 domains of nuc 28S rDNA. Although the split was fairly justified by the delineating morphological characters, there were weaknesses in the molecular analyses, which created reluctance in the scientific community to adopt these new genera for the description of new species. In this study, this issue was addressed using phylogenomics. Whole genomes of 109 strains of Pythium and close relatives were sequenced, assembled, and annotated. These data were combined with 10 genomes sequenced in previous studies. Phylogenomic analyses were performed with 148 single-copy genes represented in at least 90% of the taxa in the data set. The results showed support for the division of Pythium s.l. The status of alternative generic names that have been used for species of Pythium in the past (e.g., Artotrogus, Cystosiphon, Eupythium, Nematosporangium, Rheosporangium, Sphaerosporangium) was investigated. Based on our molecular analyses and review of the Pythium generic concepts, we urge the scientific community to adopt the generic names Pythium, Elongisporangium, Globisporangium, and their concepts as proposed by Uzuhashi and colleagues in 2010 in their work going forward. In order to consolidate the taxonomy of these genera, some of the recently described Pythium spp. are transferred to Elongisporangium and Globisporangium.

First Report of Didymella glomerata Causing Didymella Leaf Blight on Maize in China

Maize (Zea mays L.) is a staple food crop worldwide. In July 2021, gray leaf blight was observed on maize leaves in a field located in Panjin (41°7'11.98" N, 122°4'14.57" E), Liaoning Province, China. Nearly 5% of the maize plants were affected in the field. The leaves of the affected plants showed oval to oblong, gray, sunken lesions with yellow or tan margins. The lesions were scattered all over the leaf surface; however, they were absent on the stalks and other parts of the affected plants. To isolate the pathogen, leaf discs (1.25 mm2) excised from the blight lesions were surface-sterilized with 70% ethanol for 30 seconds, followed by 20% NaOCl for 2 minutes and finally rinsed three times with sterilized water. The discs were cultured on potato dextrose agar (PDA) plates supplemented with streptomycin (100 mg/L) and incubated at 25oC under a 12-h photoperiod for 7 days. Six single spore isolates (two per sampled infected leaf) were purified from the PDA culture plates. The fungal colonies of three selected isolates (one per sampled infected leaf; Pj-1, Pj-2, and Pj-3) were dark brown on the PDA plates and devoid of aerial hyphae; all three isolates grew 11 mm/day on the PDA plates. The number of conidia produced by the isolates on the 6-cm PDA plates 7 days after incubation was ranged from 160 x 108 to 208 x 108 (n = 36). Conidia were hyaline, single-celled and ellipsoidal (3.35-3.56 µm [width] x 6.47-6.70 [length] µm; n = 36). To identify the pathogen, four loci, i.e., 28S subunit (large subunit [LSU]) of the nuclear ribosomal (nr) DNA, internal transcribed spacer (ITS) region (ITS1, 5.8S subunit of nrDNA, and ITS2), the second-largest subunit of RNA polymerase II (rpb2) and β-tubulin (tub2) were amplified using the primer sets described in the study by Chen el al. 2015. BLASTn search against GenBank revealed that the four amplicon sequences originating from Pj-1, Pj-2, and Pj-3 showed 99-100% homology to the type strain CBS 528.66 of D. glomerata. A phylogenetic tree deduced from a maximum likelihood analysis of a concatenated MUSCLE-based alignment of LSU, ITS region, rpb2, and tub2 sequences of 12 isolates/strains showed that the Pj isolates clustered together with CBS 528.66, along with other D. glomerata isolates/strains, with a high bootstrap support value (i.e., 99). Based on both morphological characteristics and molecular phylogeny, Pj-1, Pj-2, and Pj-3 were identified as the D. glomerata isolates. Since the amplicon sequences of the three isolates were identical, only Pj-2 sequences were deposited in GenBank with accession numbers OM372474 (LSU), OK485138 (ITS), OM406188 (rpb2), and OK485135 (tub2). To confirm pathogenicity, 14-day-old plants (V3 growth stage) of a maize cultivar P178 were spray-inoculated with the Pj-2 conidia (1 x 107 conidia/mL) in a growth chamber. The inoculated leaves exhibited typical gray leaf blight lesions (similar to those detected in the maize field) 7 days post-inoculation at 25oC and 95-100% humidity under a 12-h photoperiod, whereas the leaves spray-inoculated with sterilized water remained healthy. The pathogenicity assay was repeated three times; the pathogen was re-isolated from the inoculated leaves each time and confirmed by the morphological characteristics and the molecular phylogeny based on the four loci to be D. glomerata, fulfilling Koch's postulates. This first report of D. glomerata causing Didymella leaf blight on maize will help develop robust disease management strategies against this emerging fungal pathogen.

Current Insight into Traditional and Modern Methods in Fungal Diversity Estimates

Fungi are an important and diverse component in various ecosystems. The methods to identify different fungi are an important step in any mycological study. Classical methods of fungal identification, which rely mainly on morphological characteristics and modern use of DNA based molecular techniques, have proven to be very helpful to explore their taxonomic identity. In the present compilation, we provide detailed information on estimates of fungi provided by different mycologistsover time. Along with this, a comprehensive analysis of the importance of classical and molecular methods is also presented. In orderto understand the utility of genus and species specific markers in fungal identification, a polyphasic approach to investigate various fungi is also presented in this paper. An account of the study of various fungi based on culture-based and cultureindependent methods is also provided here to understand the development and significance of both approaches. The available information on classical and modern methods compiled in this study revealed that the DNA based molecular studies are still scant, and more studies are required to achieve the accurate estimation of fungi present on earth.

Fungal diversity notes 1512-1610: taxonomic and phylogenetic contributions on genera and species of fungal taxa

This article is the 14th in the Fungal Diversity Notes series, wherein we report 98 taxa distributed in two phyla, seven classes, 26 orders and 50 families which are described and illustrated. Taxa in this study were collected from Australia, Brazil, Burkina Faso, Chile, China, Cyprus, Egypt, France, French Guiana, India, Indonesia, Italy, Laos, Mexico, Russia, Sri Lanka, Thailand, and Vietnam. There are 59 new taxa, 39 new hosts and new geographical distributions with one new combination. The 59 new species comprise Angustimassarina kunmingense, Asterina lopi, Asterina brigadeirensis, Bartalinia bidenticola, Bartalinia caryotae, Buellia pruinocalcarea, Coltricia insularis, Colletotrichum flexuosum, Colletotrichum thasutense, Coniochaeta caraganae, Coniothyrium yuccicola, Dematipyriforma aquatic, Dematipyriforma globispora, Dematipyriforma nilotica, Distoseptispora bambusicola, Fulvifomes jawadhuvensis, Fulvifomes malaiyanurensis, Fulvifomes thiruvannamalaiensis, Fusarium purpurea, Gerronema atrovirens, Gerronema flavum, Gerronema keralense, Gerronema kuruvense, Grammothele taiwanensis, Hongkongmyces changchunensis, Hypoxylon inaequale, Kirschsteiniothelia acutisporum, Kirschsteiniothelia crustaceum, Kirschsteiniothelia extensum, Kirschsteiniothelia septemseptatum, Kirschsteiniothelia spatiosum, Lecanora immersocalcarea, Lepiota subthailandica, Lindgomyces guizhouensis, Marthe asmius pallidoaurantiacus, Marasmius tangerinus, Neovaginatispora mangiferae, Pararamichloridium aquisubtropicum, Pestalotiopsis piraubensis, Phacidium chinaum, Phaeoisaria goiasensis, Phaeoseptum thailandicum, Pleurothecium aquisubtropicum, Pseudocercospora vernoniae, Pyrenophora verruculosa, Rhachomyces cruralis, Rhachomyces hyperommae, Rhachomyces magrinii, Rhachomyces platyprosophi, Rhizomarasmius cunninghamietorum, Skeletocutis cangshanensis, Skeletocutis subchrysella, Sporisorium anadelphiae-leptocomae, Tetraploa dashaoensis, Tomentella exiguelata, Tomentella fuscoaraneosa, Tricholomopsis lechatii, Vaginatispora flavispora and Wetmoreana blastidiocalcarea. The new combination is Torula sundara. The 39 new records on hosts and geographical distribution comprise Apiospora guiyangensis, Aplosporella artocarpi, Ascochyta medicaginicola, Astrocystis bambusicola, Athelia rolfsii, Bambusicola bambusae, Bipolaris luttrellii, Botryosphaeria dothidea, Chlorophyllum squamulosum, Colletotrichum aeschynomenes, Colletotrichum pandanicola, Coprinopsis cinerea, Corylicola italica, Curvularia alcornii, Curvularia senegalensis, Diaporthe foeniculina, Diaporthe longicolla, Diaporthe phaseolorum, Diatrypella quercina, Fusarium brachygibbosum, Helicoma aquaticum, Lepiota metulispora, Lepiota pongduadensis, Lepiota subvenenata, Melanconiella meridionalis, Monotosporella erecta, Nodulosphaeria digitalis, Palmiascoma gregariascomum, Periconia byssoides, Periconia cortaderiae, Pleopunctum ellipsoideum, Psilocybe keralensis, Scedosporium apiospermum, Scedosporium dehoogii, Scedosporium marina, Spegazzinia deightonii, Torula fici, Wiesneriomyces laurinus and Xylaria venosula. All these taxa are supported by morphological and multigene phylogenetic analyses. This article allows the researchers to publish fungal collections which are important for future studies. An updated, accurate and timely report of fungus-host and fungus-geography is important. We also provide an updated list of fungal taxa published in the previous fungal diversity notes. In this list, erroneous taxa and synonyms are marked and corrected accordingly.

A Novel Real Time PCR Method for the Detection and Quantification of Didymella pinodella in Symptomatic and Asymptomatic Plant Hosts

Didymella pinodella is the major pathogen of the pea root rot complex in Europe. This wide host range pathogen often asymptomatically colonizes its hosts, making the control strategies challenging. We developed a real-time PCR assay for the detection and quantification of D. pinodella based on the TEF-1 alpha gene sequence alignments. The assay was tested for specificity on a 54-isolate panel representing 35 fungal species and further validated in symptomatic and asymptomatic pea and wheat roots from greenhouse tests. The assay was highly consistent across separate qPCR reactions and had a quantification/detection limit of 3.1 pg of target DNA per reaction in plant tissue. Cross-reactions were observed with DNA extracts of five Didymella species. The risk of cross contamination, however, is low as the non-targets have not been associated with pea previously and they were amplified with at least 1000-fold lower sensitivity. Greenhouse inoculation tests revealed a high correlation between the pathogen DNA quantities in pea roots and pea root rot severity and biomass reduction. The assay also detected D. pinodella in asymptomatic wheat roots, which, despite the absence of visible root rot symptoms, caused wheat biomass reduction. This study provides new insights into the complex life style of D. pinodella and can assist in better understanding the pathogen survival and spread in the environment.

New Dothideomycetes from Freshwater Habitats in Spain

The Dothideomycetes are a class of cosmopolitan fungi that are present principally in terrestrial environments, but which have also been found in freshwater and marine habitats. In the present study, more than a hundred samples of plant debris were collected from various freshwater locations in Spain. Its incubation in wet chambers allowed us to detect and to isolate in pure culture numerous fungi producing asexual reproductive fruiting bodies (conidiomata). Thanks to a morphological comparison and to a phylogenetic analysis that combined the internal transcribed spacer (ITS) region of the nrDNA with fragments of the RNA polymerase II subunit 2 (rpb2), beta tubulin (tub2), and the translation elongation factor 1-alpha (tef-1) genes, six of those strains were identified as new species to science. Three belong to the family Didymellaceae: Didymella brevipilosa, Heterophoma polypusiformis and Paraboeremia clausa; and three belong to the family Phaeosphaeriaceae:Paraphoma aquatica, Phaeosphaeria fructigena and Xenophoma microspora. The finding of these new taxa significantly increases the number of the coelomycetous fungi that have been described from freshwater habitats.

Fungal Planet description sheets: 1284-1382

Novel species of fungi described in this study include those from various countries as follows: Antartica, Cladosporium austrolitorale from coastal sea sand. Australia, Austroboletus yourkae on soil, Crepidotus innuopurpureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium, Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil, Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada, Cuphophyllus bondii from a grassland. Croatia, Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus, Amanita exilis on calcareous soil. Czech Republic, Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark, Lasiosphaeria deviata on pieces of wood and herbaceous debris. Dominican Republic, Calocybella goethei among grass on a lawn. France (Corsica), Inocybe corsica on wet ground. France (French Guiana), Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. Germany, Paramicrothecium sambuci (incl. Paramicrothecium gen. nov.) on dead stems of Sambucus nigra. India, Aureobasidium microtermitis from the gut of a Microtermes sp. termite, Laccaria diospyricola on soil and Phylloporia tamilnadensis on branches of Catunaregam spinosa. Iran, Pythium serotinoosporum from soil under Prunus dulcis. Italy, Pluteus brunneovenosus on twigs of broadleaved trees on the ground. Japan, Heterophoma rehmanniae on leaves of Rehmannia glutinosa f. hueichingensis. Kazakhstan, Murispora kazachstanica from healthy roots of Triticum aestivum. Namibia, Caespitomonium euphorbiae (incl. Caespitomonium gen. nov.) from stems of an Euphorbia sp. Netherlands, Alfaria junci, Myrmecridium junci, Myrmecridium juncicola, Myrmecridium juncigenum, Ophioceras junci, Paradinemasporium junci (incl. Paradinemasporium gen. nov.), Phialoseptomonium junci, Sporidesmiella juncicola, Xenopyricularia junci and Zaanenomyces quadripartis (incl. Zaanenomyces gen. nov.), from dead culms of Juncus effusus, Cylindromonium everniae and Rhodoveronaea everniae from Evernia prunastri, Cyphellophora sambuci and Myrmecridium sambuci from Sambucus nigra, Kiflimonium junci, Sarocladium junci, Zaanenomyces moderatricis-academiae and Zaanenomyces versatilis from dead culms of Juncus inflexus, Microcera physciae from Physcia tenella, Myrmecridium dactylidis from dead culms of Dactylis glomerata, Neochalara spiraeae and Sporidesmium spiraeae from leaves of Spiraea japonica, Neofabraea salicina from Salix sp., Paradissoconium narthecii (incl. Paradissoconium gen. nov.) from dead leaves of Narthecium ossifragum, Polyscytalum vaccinii from Vaccinium myrtillus, Pseudosoloacrosporiella cryptomeriae (incl. Pseudosoloacrosporiella gen. nov.) from leaves of Cryptomeria japonica, Ramularia pararhabdospora from Plantago lanceolata, Sporidesmiella pini from needles of Pinus sylvestris and Xenoacrodontium juglandis (incl. Xenoacrodontium gen. nov. and Xenoacrodontiaceae fam. nov.) from Juglans regia. New Zealand, Cryptometrion metrosideri from twigs of Metrosideros sp., Coccomyces pycnophyllocladi from dead leaves of Phyllocladus alpinus, Hypoderma aliforme from fallen leaves Fuscopora solandri and Hypoderma subiculatum from dead leaves Phormium tenax. Norway, Neodevriesia kalakoutskii from permafrost and Variabilispora viridis from driftwood of Picea abies. Portugal, Entomortierella hereditatis from a biofilm covering a deteriorated limestone wall. Russia, Colpoma junipericola from needles of Juniperus sabina, Entoloma cinnamomeum on soil in grasslands, Entoloma verae on soil in grasslands, Hyphodermella pallidostraminea on a dry dead branch of Actinidia sp., Lepiota sayanensis on litter in a mixed forest, Papiliotrema horticola from Malus communis, Paramacroventuria ribis (incl. Paramacroventuria gen. nov.) from leaves of Ribes aureum and Paramyrothecium lathyri from leaves of Lathyrus tuberosus. South Africa, Harzia combreti from leaf litter of Combretum collinum ssp. sulvense, Penicillium xyleborini from Xyleborinus saxesenii, Phaeoisaria dalbergiae from bark of Dalbergia armata, Protocreopsis euphorbiae from leaf litter of Euphorbia ingens and Roigiella syzygii from twigs of Syzygium chordatum. Spain, Genea zamorana on sandy soil, Gymnopus nigrescens on Scleropodium touretii, Hesperomyces parexochomi on Parexochomus quadriplagiatus, Paraphoma variabilis from dung, Phaeococcomyces kinklidomatophilus from a blackened metal railing of an industrial warehouse and Tuber suaveolens in soil under Quercus faginea. Svalbard and Jan Mayen, Inocybe nivea associated with Salix polaris. Thailand, Biscogniauxia whalleyi on corticated wood. UK, Parasitella quercicola from Quercus robur. USA, Aspergillus arizonicus from indoor air in a hospital, Caeliomyces tampanus (incl. Caeliomyces gen. nov.) from office dust, Cippumomyces mortalis (incl. Cippumomyces gen. nov.) from a tombstone, Cylindrium desperesense from air in a store, Tetracoccosporium pseudoaerium from air sample in house, Toxicocladosporium glendoranum from air in a brick room, Toxicocladosporium losalamitosense from air in a classroom, Valsonectria portsmouthensis from air in men's locker room and Varicosporellopsis americana from sludge in a water reservoir. Vietnam, Entoloma kovalenkoi on rotten wood, Fusarium chuoi inside seed of Musa itinerans, Micropsalliota albofelina on soil in tropical evergreen mixed forests and Phytophthora docyniae from soil and roots of Docynia indica. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Osieck ER, Jurjević Ž, et al. 2021. Fungal Planet description sheets: 1284-1382. Persoonia 47: 178-374. https://doi.org/10.3767/persoonia.2021.47.06.

Toward a Natural Classification of Botryosphaeriaceae: A Study of the Type Specimens of Botryosphaeria sensu lato

The genus Botryosphaeria includes more than 200 epithets, but only the type species, Botryosphaeria dothidea and a dozen or more other species have been identified based on DNA sequence data. The taxonomic status of the other species remains unconfirmed because they lack either morphological information or DNA sequence data. In this study, types or authentic specimens of 16 "Botryosphaeria" species are reassessed to clarify their identity and phylogenetic position. nuDNA sequences of four regions, ITS, LSU, tef1-α and tub2, are analyzed and considered in combination with morphological characteristics. Based on the multigene phylogeny and morphological characters, Botryosphaeria cruenta and Botryosphaeria hamamelidis are transferred to Neofusicoccum. The generic status of Botryosphaeria aterrima and Botryosphaeria mirabile is confirmed in Botryosphaeria. Botryosphaeria berengeriana var. weigeliae and B. berengeriana var. acerina are treated synonyms of B. dothidea. Botryosphaeria mucosa is transferred to Neodeightonia as Neodeightonia mucosa, and Botryosphaeria ferruginea to Nothophoma as Nothophoma ferruginea. Botryosphaeria foliicola is reduced to synonymy with Phyllachorella micheliae. Botryosphaeria abuensis, Botryosphaeria aesculi, Botryosphaeria dasylirii, and Botryosphaeria wisteriae are tentatively kept in Botryosphaeria sensu stricto until further phylogenetic analysis is carried out on verified specimens. The ordinal status of Botryosphaeria apocyni, Botryosphaeria gaubae, and Botryosphaeria smilacinina cannot be determined, and tentatively accommodate these species in Dothideomycetes incertae sedis. The study demonstrates the significance of a polyphasic approach in characterizing type specimens, including the importance of using of DNA sequence data.

Phytotoxins produced by Didymella glomerata and Truncatella angustata, associated with grapevine trunk diseases (GTDs) in Iran

Didymella glomerata and Truncatella angustata associated with grapevine trunk diseases (GTDs) in Iran, were grown in vitro to evaluate the production of phytotoxic metabolites as potential pathogenicity determinants. 2,5-Dihydroxymethylfuran and (+)-6-hydroxyramulosin were isolated from the culture filtrates of D. glomerata and T. angustata, respectively. They were identified by physical and spectroscopic (essentially 1 D and 2 D ¹H and ¹³C NMR and ESIMS) methods and X ray analysis. Both compounds induced significant necrosis and curling on the leaves of the host plant Vitis vinifera L. and the effects were concentration dependent. No effect was observed on the leaves of the non-host Solanum lycopersicum L.. plant.

First Characterisation of the Phoma Species Complex on Maize Leaves in Central Europe

In the last decade, the cultivated area of maize has increased in Central Europe due to its high yield potential and diverse uses for feed and bio-energy. This has led to more intense maize cultivation, with narrowed crop rotations resulting in the increase in maize leaf diseases. During 2012 and 2013, an inventory of maize leaf spot diseases was carried out in various regions in Central Europe. In addition to the major leaf pathogens, isolates of Phoma-like species were obtained from oval to elliptical spots on leaves or found in lesions produced by other leaf pathogens. A total of 16 representative Phoma-like strains were characterised for their pathogenicity on maize leaves, for their morphological characteristics and with a phylogenetic analysis based on multilocus sequence analysis using part of the actin (ACT), calmodulin (CAL), β-tubulin (TUB), internal transcribed spacer (ITS) region of ribosomal DNA and large subunit ribosomal RNA (LSU) genes. The strains were grouped into four clades, and morphological studies supported this classification for most of them. Strains were compared with six reference Phoma-like species strains from the Westerndijk Fungal Biodiversity Institute collection reported to colonise maize. The pathogenic group of strains from our collection (after completion of Koch's postulates) did not cluster with any of these species, indicating a different and novel Phoma-like species infecting maize leaves. To our knowledge, this is the first study dissecting the Phoma species complex on maize leaves in Central Europe.

Beyond Sea Turtles: Fusarium keratoplasticum in Eggshells of Podocnemis unifilis, a Threatened Amazonian Freshwater Turtle

The endangered yellow-spotted river turtle (Podocnemis unifilis) has experienced a dramatic population decline in the Ecuadorian Amazonia, mainly due to overexploitation of its eggs. To reverse this trend, the Wildlife Conservation Society has developed a head-start program in Yasuní National Park since 2008, but the potential risk that microbes associated with its eggs might represent for hatching success has not been evaluated yet. Members of the Fusarium solani species complex (FSSC) are involved in egg failure in sea turtles under natural and hatchery conditions, but their role in infecting the eggs of P. unifilis is unknown. In this study, we collected eggshells of P. unifilis and obtained 50 fungal and bacterial isolates. Some potentially pathogenic fungi of the genera Fusarium, Penicillium and Rhizopus were identified based on molecular data. Most importantly, the sea turtle pathogenic species F. keratoplasticum not only was present, but it was the most frequently found. Conversely, we have also isolated other microorganisms, such as Pseudomonas or Phoma-like species, producing a wide spectrum of antifungal compounds that may have a protective role against fungal diseases. Our survey provides useful information on potential pathogens found in P. unifilis eggshells, upon which the success of conservation programs may depend.

A new pleosporalean fungus isolated from superficial to deep human clinical specimens

Human infections by pleosporalean fungi (class Dothideomycetes, phylum Ascomycota) are rarely reported. Because their identification is challenging using morphological characterization, several phylogenetic markers must be sequenced for an accurate identification and taxonomical placement of the isolates. Three isolates of clinical origin were phenotypically characterized, but due to the absence of relevant morphological traits, D1-D2 domains of the 28S nrRNA gene (LSU), the internal transcribed spacer region (ITS) of the nrRNA, and fragments of the RNA polymerase II subunit 2 (rpb2) and translation elongation factor 1-alpha (tef1) genes were sequenced to allow a phylogenetic analysis that would solve their phylogenetic placement. That analysis revealed that these isolates did not match any previously known pleosporalean genera, and they are proposed here as the new fungal genus, Gambiomyces. Unfortunately, the isolates remained sterile, which, consequently, made the morphological description of the reproductive structures impossible. Future studies should try to understand the behaviour of this fungus in nature as well as its characteristics as an opportunistic fungal pathogen. Molecular identification is becoming an essential tool for proper identification of Dothideomycetes of clinical origin.

LAY ABSTRACT

We describe a new pleosporalen pathogenic fungus, Gambiomyces profunda, found in superficial to deep samples from a human patient. Because all strains remained sterile, the fungus was finally identified following a phylogenetic analysis by using four different molecular markers.