Search Results (138)

The actinobacterial strain DEC002 was isolated recently from volcanic soils of Deception Island. Its taxonomic identity was resolved through a polyphasic strategy integrating morphology, physiological profiling, multilocus phylogeny, and genome-wide comparisons to resolve its identity. Concatenated core gene trees together with average nucleotide identity and digital DNA–DNA hybridization values place DEC002 within Actinacidiphila fildesensis with robust support. This is the first molecular confirmation of the species beyond King George Island and secures a second verified locality within the South Shetland Archipelago. Growth at low temperature with tolerance to moderate salinity indicates a psychrotolerant lifestyle. Cell-free supernatants inhibited representatives of foodborne Gram-negative and Gram-positive bacteria, including representatives of Enterobacteriaceae, Vibrio, Staphylococcus and Streptococcus. Genome analysis revealed enrichment in multiple biosynthetic gene clusters for nonribosomal peptides, polyketides, terpenes, and ribosomally synthesized and post-translationally modified peptides (RiPPs), supporting the biosynthetic potential of the strain. Functional annotations emphasize replication and repair modules, mobile element-associated proteins, helix–turn–helix regulators, and versatile transport systems, features coherent with cold stress and oligotrophic soils. Antibiotic susceptibility assays indicate a broad resistance phenotype under the experimental conditions tested, together with extracellular antimicrobial activity. These data refine the biogeography of A. fildesensis and indicate DEC002 as a credible Antarctic source of specialized metabolites with antimicrobial promise. Full article

Pomegranate heart rot (black heart) was observed in several pomegranate-growing areas of Algeria. From 2022 to 2025, surveys were conducted across 15 provinces (20 localities), and a total of 85 fruits (symptomatic and asymptomatic) were collected. Fruits were cut transversely to assess internal symptoms, ranging from early aril browning to dry black rot. Thirty Alternaria isolates were obtained and grouped into four morphotypes based on colony and conidial morphological traits. A subset of 18 isolates was analysed by multilocus phylogeny (ITS, EF-1α, GAPDH and OPA10-2); all analysed isolates clustered within the Alternaria alternata species complex, in the clade including the ex-type strain CBS 916.96. Fruit pathogenicity tests with Algerian isolate GA reproduced typical internal heart rot symptoms, and the pathogen was consistently re-isolated from symptomatic tissues. In fruit inoculations with isolate GA, cultivars differed in susceptibility, with mean disease severities of 94%, 62% and 9.5% in ‘Taferrante’, ‘Ikhessène’ and ‘Kares’, respectively, expressed as the percentage of the fruit section presenting rot symptoms. Detached leaf assays indicated isolate-dependent differences in aggressiveness, and ‘Kares’ showed the lowest susceptibility. Overall, the results confirm that A. alternata is the causal agent of pomegranate heart rot in Algeria and provide baseline information for disease diagnosis and management. Full article

Coffea arabica, a popular beverage ingredient, is prized for its rich chemical composition, which has demonstrated significant positive effects in terms of antioxidant, anti-inflammatory, neuroprotective, and metabolic health. In November 2024, fruit rot with a 15% incidence was observed on C. arabica in Menglian city, Yunnan province, China. Symptoms began as irregular black spots that turned necrotic, wrinkled, and cracked. Fungal isolates from lesions showed morphological characteristics consistent with Fusarium coffeibaccae. Morphological data were supplemented with phylogenetic analyses based on three loci (ITS, TEF1-α, RPB2), and sequences were deposited in GenBank as for ITS (PV211189 and PV211190), TEF1-α (PQ867811 and PQ867812), and RPB2 (PV261064 and PV261065). Koch’s postulates were fulfilled on attached fruits. After 17 days at 25 °C with 70% humidity, typical rot symptoms appeared on inoculated fruits, while controls remained symptom-free. This is the first report of C. arabica fruit rot caused by F. coffeibaccae in China. This study aims to identify the aetiological agent of recently observed coffee fruit rot in Yunnan and to characterize F. coffeibaccae. It provides the first baseline data for targeted monitoring and sustainable control of F. coffeibaccae-mediated fruit rot in China’s expanding coffee sector. Full article

The taxonomic status of Arbutus pavarii Pamp., a rare and geographically restricted species endemic to northeastern Libya, has long been debated, with some treatments considering it a synonym of A. unedo. To resolve this uncertainty, we applied an integrative molecular framework that combined multilocus DNA barcoding, phylogenetic inference, and multivariate statistical analyses. Five barcode loci—nrITS, matK, rbcL, trnH–psbA, and rps16—were analyzed using barcode-gap diagnostics, TaxonDNA identification tests, and single-locus and concatenated phylogenetic analyses. Barcode-gap analyses based on Kimura 2-parameter distances revealed clear and reproducible separation between intra- and interspecific variation for A. pavarii, particularly for nrITS and the concatenated multilocus dataset, whereas conserved plastid loci showed limited discriminatory power when used individually. Phylogenetic reconstructions consistently recovered A. pavarii as a strongly supported monophyletic lineage, distinct from A. unedo and other Mediterranean congeners, with congruent topologies across the nuclear, plastid, and combined datasets. Multivariate analyses, including principal component analysis and heatmap clustering, further corroborate the genetic cohesion and distinctiveness of A. pavarii samples. Collectively, these results provide robust molecular evidence supporting the recognition of Arbutus pavarii as a distinct evolutionary lineage, rather than an intraspecific variant of A. unedo. This study established a reproducible multilocus framework for species delimitation in Arbutus and highlighted the importance of integrating nuclear and plastid markers to resolve complex taxonomic relationships. The clarified taxonomic status of A. pavarii has important implications for biodiversity assessment and conservation planning in the Mediterranean region, particularly in the Cyrenaican floristic province. Full article

Anthracnose is one of the most destructive diseases of avocado worldwide; however, foliar infections remain poorly documented in Peru. We investigated the etiology of necrotic leaf lesions observed in avocado plantations in Amazonas and assessed the in vitro antifungal activity of two Piper essential oils (EOs). Incidence was quantified in a 420-tree plot (n = 150 plants). Two representative isolates (MGS03, MGS04) were obtained from symptomatic leaves and characterized by morphology and multilocus sequencing (ITS, CHS-1, ACT, and TUB2). Maximum-likelihood phylogeny within the C. gloeosporioides species complex clustered with C. fructicola. Pathogenicity tests on detached leaves (unwounded inoculation) reproduced field symptoms and fulfilled Koch’s postulates. The antifungal activity of Piper carpunya and P. aduncum EOs (50–1000 µL L⁻¹) was evaluated using poisoned-medium assays, revealing a strong dose-dependent inhibition of mycelial growth. Inhibition reached >89.8% at 500 µL L⁻¹ and ~100% at 1000 µL L⁻¹, with P. aduncum showing slightly higher activity. This study provides the first confirmed record of C. fructicola associated with necrotic leaf lesions in avocado in Peru and demonstrates the promising antifungal potential of Piper EOs as eco-friendly candidates for anthracnose management. Full article

Species of the ascomycetous genus Cladobotryum (Hypocreales, Hypocreaceae) are ecologically and economically important mycoparasites that cause cobweb disease in cultivated and wild mushrooms. Despite their significance as fungal pathogens and producers of bioactive metabolites, the taxonomy of Cladobotryum remains unresolved due to extensive morphological plasticity, complex teleomorph–anamorph connections, and the presence of cryptic species. This study employs an integrative approach combining micro- and macromorphological characterization, multi-locus phylogeny (ITS, rpb2, and tef-1a), and comparative genomics to clarify the taxonomic position of the Greek isolate Cladobotryum sp. ATHUM 6904, previously designated as an unclassified red-pigmented (URP) strain. Phylogenetic analyses demonstrated that URP strains form a distinct, well-supported clade closely related to C. tenue and C. rubrobrunnescens, yet genetically and morphologically distinct from both. Comparative genomic analyses of isolate ATHUM 6904 and the ex-type strains of C. tenue and C. rubrobrunnescens revealed pronounced divergence in transposable element content, mitochondrial genome architecture, gene order, orthologous gene composition, secondary metabolite biosynthetic potential, and overall genomic distance. Micro- and macromorphological comparisons further supported the differentiation of isolate ATHUM 6904 from both reference species. Based on the combined molecular, morphological, and genomic evidence, the Greek isolate ATHUM 6904 is described as a novel species, Cladobotryum rhodochroum sp. nov. Full article

Shanxi Province, located in northern China, characterized by a warm-temperate monsoon climate, complex mountainous topography, and vegetation dominated by trees of Fagaceae and Pinaceae, provides diverse habitats for Russula diversity. Recent investigations on macrofungi in this region revealed nine new Russula species based on integrated morphological and multi-locus phylogenetic analyses (ITS, nrLSU, rpb2, tef1), which are described and illustrated in this paper. These new taxa are classified into three subgenera of Russula: one species of subgen. Brevipes, four of subgen. Heterophyllidia, four of subgen. Russula. This work enhances the understanding of Russula resources in China’s temperate zone. Full article

Lentinula edodes (shiitake) is a major edible and medicinal mushroom and a key component of the horticultural mushroom industry in East Asia. During April–June 2024 cropping season, a widespread blue mold outbreak was observed on bag-cultivated shiitake in Xixia County, Henan Province, China. Affected cultivation rooms showed extensive blue-green sporulation on the exposed surfaces of substrate blocks and on developing and mature fruiting bodies, leading to rapid loss of marketability. To clarify the etiology of this disease, we coupled field surveys with morphological, molecular, and pathogenicity analyses. Fifty-five Penicillium isolates were obtained from symptomatic cultivation bags. Three representative isolates (LE06, LE15, and LE26) were characterized in detail. Colonies on PDA produced velutinous to floccose mycelia with blue-green conidial masses and terverticillate penicilli bearing smooth-walled, globose conidia. Sequencing of four loci—the internal transcribed spacer (ITS1-5.8S-ITS2), β-tubulin (benA), calmodulin gene (CaM), and RNA polymerase II second largest subunit (rpb2)—followed by multilocus phylogenetic analysis placed all three isolates in a well-supported clade with the ex-type CBS 227.28 of Penicillium bialowiezense. Inoculation of healthy shiitake cultivation bags with conidial suspensions (1 × 10⁶ conidia mL⁻¹) reproduced typical blue mold symptoms on substrate surfaces and fruiting bodies within 40 days post inoculation, whereas mock-inoculated controls remained symptomless. The pathogen was consistently reisolated from diseased tissues and showed identical ITS and benA sequences to the inoculated strains, thereby fulfilling Koch’s postulates. This is the first confirmed report of P. bialowiezense causing blue mold on shiitake, and it expands the known host range of this species. Our findings highlight the vulnerability of bag cultivation systems to airborne Penicillium contaminants and underscore the need for improved hygiene, environmental management, and targeted diagnostics in commercial shiitake production. Full article

Species delimitation in Charipinae hyperparasitoids (Hymenoptera: Figitidae) is notoriously difficult due to their minute size and limited morphological variability. Traditional diagnostic characters sometimes show intraspecific variation, raising concerns about their reliability. Here, we applied an integrative taxonomic framework to evaluate species boundaries among six species of Alloxysta Förster and four species of Phaenoglyphis Förster. We combined a morphological dataset of 53 characters with data from three molecular markers (COI, ITS2, and 16S rRNA) and reconstructed phylogenies under maximum-likelihood criteria. Phylogenies consistently recovered morphologically defined taxa as well-supported clades, confirming the overall reliability of traditional characters (pronotal and propodeal carinae, radial cell shape, and flagellomere proportions). On the other hand, molecular evidence refined certain species limits and highlighted cases of potential cryptic variation. Our results demonstrate that morphology still provides a strong baseline for Charipinae taxonomy, but integration with molecular data yields more robust and stable classifications. This study underscores the value of multi-locus approaches for resolving taxonomic ambiguities and provides a framework for future ecological and evolutionary research on these hyperparasitoid wasps. Full article

The Poaceae family, commonly known as grasses, is one of the most strategically important plant groups on earth. They are globally distributed, found in virtually every terrestrial habitat on earth, from deserts and grasslands to forests and wetlands. An investigation was conducted on the fungi associated with grasses in Sichuan and Guizhou Provinces, China. Based on morphological characteristics and multi-locus phylogenetic analyses (from Maximum Likelihood (ML) and Bayesian Inference (BI)) of combined LSU, SSU, ITS, and tef1-α sequence data, a new genus, Neokeissleriella, and three novel species—Keissleriella guttata, K. sichuanensis, and Neokeissleriella fusispora—were introduced. Two new host records of Keissleriella caraganae, K. yunnanensis and a new geographical record of K. gloeospora in Sichuan Province, China, are reported. To substantiate the newly established taxa, detailed morphological descriptions and illustrations are provided and supported with molecular phylogenetic analysis. This study broadens the understanding of fungal diversity on Poaceae hosts in Sichuan and Guizhou provinces, China, revealing the high potential for identifying novel taxa. Full article

Trichoderma species are globally distributed fungi with remarkable biotechnological relevance. In this study, we describe two new species, T. jilotepecense and T. sanisidroense, and report T. endophyticum as the first record for Mexico. All isolates were obtained from soils of coffee agroecosystems in Veracruz. Species identification was based on the integration of cultural and micromorphological characteristics (PDA, SNA, CMD; 25–35 °C) with multilocus phylogenetic analyses using the ITS, tef1, and rpb2 markers. The concatenated dataset provided strong support for species delimitation and clarified phylogenetic relationships within the Harzianum and Virens clades. Full article

This study investigated the molecular epidemiology, virulence, antimicrobial resistance, and mobile genetic elements (MGEs) of Salmonella enterica serovar I 4,[5],12:i:- isolates collected in Jeollanam-do, South Korea, between 2021 and 2023. A total of 135 isolates were tested for antimicrobial susceptibility and 14 virulence-associated genes were screened by PCR. Pulsed-field gel electrophoresis (PFGE) assessed clonal relatedness, and whole-genome sequencing (WGS) enabled multilocus sequence typing (MLST), core genome MLST (cgMLST), SNP phylogeny, resistance gene detection, and MGE analysis. Nine virulence profiles (VP1–VP9) were identified. VP1 (74.1%) was strongly associated with multidrug resistance (MDR), while VP2 (14.8%), which carried plasmid-encoded spv genes, remained largely susceptible. Overall, 83.7% of isolates were resistant to at least one antimicrobial, and 65.2% were MDR, with ampicillin and tetracycline consistently forming the backbone of MDR phenotypes. PFGE revealed high genetic diversity, with 72 pulsotypes, yet certain clones (e.g., SMOX01.006, SMOX01.012) were widely distributed and corresponded to VP2 isolates. WGS confirmed two dominant sequence types, ST34 (n = 24) and ST19 (n = 20), with SNP phylogeny showing VP1 isolates mainly clustered with ST34 and VP2 with ST19. Genotype–phenotype concordance showed strong agreement for most antimicrobials, except cefoxitin, ciprofloxacin, amikacin, and trimethoprim/sulfamethoxazole. MGE analysis revealed that tet(B) was consistently associated with ISVsa5, while ISEc59 was linked to multiple resistance genes, though only aac(3)-IV was phenotypically expressed. These findings demonstrate that MDR and virulence gene composition were closely associated with clonal clustering and that MGEs may contribute to resistance gene expression. This study provides a basis for understanding the dissemination of resistant and virulent Salmonella in the region and underscores the need for continuous genomic surveillance. Full article

Postharvest diseases caused by various fungal pathogens pose a significant threat to fruit quality, storage, and market value, making their identification and biological characterization essential for effective management strategies. This study examines the morphological and phylogenetic characteristics of Alternaria, Botryosphaeria, Pestalotiopsis, and Trichothecium species associated with loquat fruit rot in Yunnan, China. In May 2023, fruit rot of loquat in Yunnan, China, was classified into four types: ring rot, brown spot, black spot, and soft rot, with incidence rates of 4%, 6%, 6%, and 12%, respectively. Based on morphological features and molecular approaches, two strains of Botryosphaeria were identified as Botryosphaeria dothidea, which causes ring rot. Three strains of Trichothecium were identified as Trichothecium roseum, which is responsible for the brown spots. Three strains of Alternaria were identified as Alternaria alternata, which led to the appearance of black spots on the leaves. Similarly, two strains of Pestalotiopsis were identified as Pestalotiopsis kenyana, which causes soft rot. All identified species were verified to induce harvest loquat fruit rot by validating Koch’s postulates. This is the novel report of B. dothidea, T. roseum, and P. kenyana inducing postharvest fruit rot on loquat in Yunnan, China, and globally. It is also the first evidence that A. alternata causes postharvest fruit rot and gray leaf spot on loquat in Yunnan, China. The virulence differed among species, even within isolates of the same species. Additionally, the effect of temperature on the pathogenicity of A. alternata on loquat leaves was more than humidity. These findings enhance our understanding of the fungal pathogens affecting loquat fruit in the study area and highlight the importance of effective management strategies to minimize fruit rot. Further research is needed to investigate the ecological impacts of these species and potential control measures in agricultural practices. Full article

The Stockholm Paradigm, a multilevel framework for studying coevolutionary interactions, it is a promising method for obtaining a globally relevant understanding of the emergence of present and past host–parasite and insect–plant interactions. This research aimed to expand the application of the Paradigm to virus–host interactions, considering that viruses are being subjected to the same evolutionary forces as any other living organism. By applying different data science techniques, we described and discussed capacity and opportunity traits for Influenza A H1N1 strains, and how they might influence the pathogen’s host repertoire evolution, and thus ranked different strains according to their emergence risk in the human population. We hope to contribute to the application of different methods for understanding disease emergence, and consequently to the development of new public health strategies for preventing (re)emerging diseases. Full article

In the main growing areas in Serbia, plants with symptoms of stem blight were sampled in nine orchards with American highbush blueberry (Vaccinium corymbosum), cultivar ‘Duke’, with high disease incidence, and 153 samples were taken. A total of 128 Botryosphaeriaceae isolates were characterized on the basis of morphology, sequence analysis, multilocus phylogeny based on ITS, TEF1-α and TUB2 sequences and pathogenicity, and belonged to one of the four species Neofusicoccum parvum, Botryosphaeria dothidea, Diplodia seriata and Lasiodiplodia iraniensis. Both D. seriata and L. iraniensis were detected for the first time on blueberries in Serbia, and L. iraniensis was detected for the first time on blueberries worldwide. Comparative morphological and TEF1-α sequence analyses allowed a clear separation of L. iraniensis from the phylogenetically closely related L. fujianensis, L. thailandica and L. endophytica. Of the nine blueberry cultivars ‘Aurora’, ‘Barbara Ann’, ‘Bluecrop’, ‘Bluejay’, ‘Draper’, ‘Duke’, ‘Huron’, ‘Patriot’ and ‘Spartan’ inoculated with L. iraniensis (isolate 421-19), the cultivar ‘Duke’ was the most susceptible. In our study, the majority of orchards were in their second or third year of production, implying that the planting material is likely to be the source of infection, emphasizing the importance of pathogen-free planting material. Full article