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Alpine treeline and shrubline ecotones are climatically sensitive transition zones where vegetation shifts strongly influence belowground microbial processes. Soil bacteria and fungi, as core component of the soil microbiome, play vital roles in nutrient cycling and plant–soil interactions within these fragile ecosystems. However, the structure and diversity of soil microbial communities across the treeline–shrubline transition remain poorly understood. Here, we investigated soil bacterial and fungal communities across treeline and shrubline ecotones in two mountain on the eastern Tibetan Plateau. We further examined how soil physicochemical properties shaped microbial community assembly. Our results demonstrated that the community composition of both bacteria and fungi differed significantly between the treeline and shrubline ecotones, while the Shannon index showed no significant variation. At the phylum level, Proteobacteria, Actinobacteriota, and Acidobacteriota dominated bacterial communities, while Ascomycota and Basidiomycota were the predominant fungal phyla. Both the network complexity of soil bacterial and fungal communities changed significantly across ecotones. Specifically, bacterial network complexity increased significantly toward the shrubline, whereas fungal network complexity declined. Bacterial community compositions were co-regulated by both environmental and vegetation factors, while fungal community compositions were only regulated by soil pH. Redundancy analysis revealed that soil organic carbon, pH, and moisture were the primary drivers of bacterial community (38.17%), whereas vegetation cover, soil organic carbon, and moisture explained the largest proportion of fungal community (44.79%). Our findings reveal the distribution patterns and underlying shift mechanisms of microbial communities between the treeline and shrubline ecotone. These insights are crucial for mountain biodiversity conservation and for improving predictions of forest responses to climate change. Full article

Aiming to clarify the spatial distribution characteristics of soil microbial assemblages and the environmental factors shaping them across a narrow altitudinal transect, this investigation concentrated on the surface soil layer within naturally occurring mixed forests of Picea crassifolia and Betula platyphylla, situated in the elevation band from 2400 to 2800 m along the southern flank of the Qilian Mountains. Leveraging the Illumina NextSeq 2000 high-throughput sequencing platform, integrated with α- and β-diversity analyses and redundancy analysis (RDA), we systematically characterized the composition and diversity traits of soil bacterial and fungal communities, as well as their associations with environmental factors. Notably, the bacterial communities were dominated by Pseudomonadota, Actinomycetota, and Acidobacteria with the abundance of Pseudomonadota decreasing with increasing altitude and that of Acidobacteria increasing with increasing altitude. Furthermore, Ascomycota and Basidiomycota were the dominant phyla in the fungal community. In contrast, bacterial α-diversity—as estimated by the Ace index—showed no significant variation across altitudes. Yet, the fungal alpha diversity metrics—namely Ace and Chao1—were markedly elevated at the 2800 m elevation relative to those observed at both intermediate and lower-altitude locations. Importantly, fungal diversity and community composition showed stronger altitudinal differentiation than bacterial communities in this dataset. Moreover, soil pH, total phosphorus, organic carbon, litter C:N:P stoichiometric ratios, and microbial biomass C:N:P stoichiometric ratios were strongly associated with soil microbial community variation along the altitude gradient, suggesting that they may act as important environmental filters. In conclusion, altitude-driven variations in litter characteristics and soil physicochemical properties jointly shape the assembly processes and spatial distribution patterns of soil microbial communities in this region. Full article

The Ningxia Yellow River Irrigation District in China has long been influenced by flood irrigation and intensive fertilizer input under its particular geological and climatic constraints, and this region is characterized by low soil organic matter, poor nutrient status, low permeability, high pH, and widespread salinization. This cross-sectional field study compared the soil physicochemical properties and microbial communities among saline–alkali soil (SAS), straw-returning farmland (SR), and traditionally managed farmland (FM). EC was higher in SAS (approximately 4.21 dS·m⁻¹) than in SR and FM (approximately 0.23 and 0.30 dS·m⁻¹, respectively), whereas TOC and C/N were higher in SR (approximately 1.00% and 10.58, respectively) than in FM (approximately 0.78% and 8.69) and SAS (approximately 0.43% and 8.81). Bacterial and fungal communities showed different distribution patterns among the three farmland types. Compared with fungi, bacterial community structure and richness varied more clearly across soils differing in salinity and organic matter status. Variations in microbial community composition were accompanied by differences in soil salinity and carbon- and nitrogen-related properties. Acidobacteriota was positively correlated with soil carbon and nitrogen variables and negatively correlated with pH and EC, while Ascomycota was positively correlated with total carbon (TC) and TOC. These results show that straw-returning farmland differed from saline–alkali soil and traditionally managed farmland in both soil properties and microbial community characteristics, highlighting potential soil–microbe associations in saline-affected agricultural systems. Full article

Nitrogen addition significantly affects soil aggregate stability by altering the aggregate microenvironment. Although the ecological effects of nitrogen addition on soil aggregates have been extensively investigated, studies specifically focusing on the responses of soil aggregate stability in Larix olgensis forest understories remain scarce. The effects of different forms of nitrogen addition (urea (CO(NH₂)₂), ammonium chloride (NH₄Cl), and sodium nitrate (NaNO₃)) were investigated at 20 kg N·ha⁻¹·yr⁻¹ across all treatments, and the physicochemical properties, stability, and microbial community composition of soil aggregates were determined to analyze soil aggregate stability. NaNO₃ significantly increased soil nutrient contents, promoted the formation of macroaggregates, and significantly enhanced soil aggregate stability. NH₄Cl significantly decreased bacterial diversity in microaggregates, while NaNO₃ significantly elevated fungal diversity in macroaggregates. CO(NH₂)₂ and NH₄Cl increased the relative abundances of Ascomycota and Proteobacteria in microaggregates, whereas NaNO₃ elevated the relative abundances of Mortierellomycota and Gemmatimonadetes in soil aggregates of all particle sizes. These results indicated that NaNO₃ was more effective in improving soil aggregate stability and exerted regulatory effects on microbial community structure compared to the other nitrogen forms. These findings can provide a theoretical basis for an in-depth understanding of the microecological processes of forest soil aggregates under the context of nitrogen deposition. Full article

The necrotrophic pathogen Sclerotinia sclerotiorum compromises the physiological and anatomical integrity of cotton, leading to substantial economic losses due to rapid tissue necrosis, stem blight, boll rot, and leaf wilting. In this context, the use of endophytic microorganisms emerges as a promising strategy for the biocontrol of white mold. This study tested the hypothesis that endophytic fungal strains isolated from the roots of Butia purpurascens, a palm tree endemic to the Cerrado biome, could mitigate disease symptoms in Gossypium hirsutum L. To evaluate this, cotton plants were subjected to biotic stress imposed by S. sclerotiorum to assess the effectiveness of seven fungal strains in attenuating disease. The impact of the pathogen was monitored through growth variables, gas exchange, leaf temperature, chlorophyll a fluorescence, antioxidant enzyme activity, proline and malondialdehyde (MDA) levels, and the incidence of rot in petioles, leaves, and flower buds. Overall, inoculation with endophytic fungi significantly alleviated the effects of the phytopathogen, promoting vegetative growth and optimizing physiological performance. Treated plants exhibited alleviated stress in primary photochemistry, reduced non-photochemical energy dissipation, and stable carbon fixation. Additionally, efficient modulation of the antioxidant system and preservation of anatomical structures were observed, minimizing the severe symptoms of white mold. Notably, the non-pathogenic strains BP10EF (Gibberella moniliformis), BP16EF (Penicillium purpurogenum), and BP33EF (Hamigera insecticola) acted as potent physiological modulators, yielding responses similar to those of healthy plants. These results highlight the biotechnological potential of these endophytic strains, which can be explored as both growth promoters and resistance inducers in cotton against white mold. Full article

Intensive nitrogen (N) fertilization in greenhouse vegetable systems degrades soil structure and accelerates soil carbon (C) mineralization. Biochar application can alleviate these adverse effects by enhancing aggregate stability and mediating microbially driven nutrient cycling, yet its effects across aggregate fractions remain poorly understood. Here, we investigated how biochar (0, 20, 40 t ha⁻¹) and N interact to affect aggregate stability, C mineralization, nutrient status, and microbial properties in bulk soil and four aggregate classes (large macroaggregates: LMA, > 2000 μm; small macroaggregates: SMA, 250–2000 μm; microaggregates: MA, 53–250 μm; silt + clay: S + C, < 53 μm) in vegetable soil after a 60-day incubation. Results showed that biochar–N co-application increased mean weight diameter by 27.4–30.5% and elevated soil total organic C (TOC) in LMA by 9.11–12.0% and in MA by 8.77–20.2% relative to the N-only treatment. It also reduced β-glucosidase and oxidase activities, as well as fungal and G⁻-bacterial abundance. Biochar amendment suppressed TOC mineralization by 2.7–24.6% in bulk soil and aggregate fractions, while boosting potentially mineralizable C pools by 12.5–155.7%, and thereby increasing overall mineralization potential. Structural equation modeling revealed the size-dependent regulatory mechanisms underlying these observations. Aggregate stability directly inhibited CO₂ emissions in bulk soil and SMA, while the effects in MA and S + C fractions were mediated by shifts in nutrient stoichiometry and hydrolase activities. Our findings clarified the size-dependent mechanisms by which biochar–N co-application promoted soil C sequestration, providing a theoretical basis for the sustainable management of intensive vegetable systems. Full article

Thermal processing of biomass can induce chemical transformations that lead to the formation of fluorescent carbonaceous products. In this study, six β-glucan-rich medicinal mushrooms, Ganoderma lucidum, Cordyceps sinensis, Inonotus obliquus, Lentinula edodes, Grifola frondosa, and Hericium erinaceus, were subjected to mild pyrolytic treatment (200 °C for 3 h) to investigate the formation of water-soluble fluorescent fractions. Physicochemical characterization of aqueous extracts was performed using high-performance liquid chromatography size-exclusion chromatography (HPLC-SEC), fluorescence emission spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and β-glucan quantification. Fluorescence emission spectra revealed species-dependent differences in emission intensity, with the most pronounced signals observed for G. lucidum and C. sinensis. HPLC-SEC analysis showed only minor changes in molecular weight distribution after thermal treatment, suggesting limited polymer degradation. FTIR spectra indicated moderate structural modifications consistent with partial carbonization and chemical rearrangement within the mushroom matrices. Despite the mild processing conditions, measurable increases in fluorescence intensity were observed in several species, indicating the formation of fluorescent carbon-rich molecular structures. These findings demonstrate that moderate thermal treatment of β-glucan-rich fungal biomass can generate water-soluble fluorescent carbonaceous fractions without extensive breakdown of the original polysaccharide matrix. The results provide new insights into thermally induced photophysical changes in medicinal mushrooms and contribute to understanding the formation of fluorescent carbonaceous products from natural biomaterials. Full article

Diseases of the nasal cavity have a diverse etiology and cause severe disorders in animals. Conidiobolomycosis is a type of zygomycosis caused by the fungus Conidiobolus spp., occurring more frequently in sheep. The objective of this study is to describe the clinical and epidemiological characteristics, as well as microbiological and histopathological findings, of an outbreak of conidiobolomycosis in sheep. A total of 12 animals out of a herd of 70 were affected, representing a morbidity of 17.1%; mortality and lethality were 11.4% (8/70) and 66.6% (8/12), respectively, of which 4 sheep died spontaneously and 4 were euthanized for diagnostic purposes due to the severity of the clinical condition. Necropsy was performed on 4 (33.3%) of the 12 affected animals, and after opening the skull in the sagittal section, a friable mass with coloration ranging from whitish-yellow to gray-green, as well as areas of necrosis, were evident in regions such as the nasal meatus, conchae, nasopharynx, hard palate, cribriform plate, meninges, and frontal lobe of the brain. Conidiobolus lamprauges was isolated from samples collected from 6 animals from nasal discharge, fungal granuloma, and intranasal swab. Reproductive structures consistent as kind of zygospores with C. lamprauges and C. incongruus were also identified. Regarding the clinical form, animals 1, 2, 3, and 4 presented manifestations of the nasopharyngeal form, with the first three progressing to the rhinocerebral form; in animal 5, the clinical form found was rhinofacial. It is concluded that clinical signs may vary with the presentation of the disease as well as the involved agent. Early diagnostic alternatives such as fungal isolation from material collected from intranasal swabs can be useful and employed in affected herds, enabling earlier intervention. Full article

Fungal decay fundamentally alters moisture transport in wood through complex bio-physical coupling mechanisms that remain poorly understood. Brown-rot fungi such as Coniophora puteana (Schumach.: Fr.) P. Karst. degrade wood through chelator-mediated Fenton (CMF) chemistry, producing hydroxyl radicals that depolymerise cellulose and hemicellulose before significant mass loss. This diffusion-dependent process requires elevated moisture content and leads to structural degradation. However, existing models fail to capture the interaction between boundary-driven fungal colonization, decay-induced property changes, and multi-phase multi-Fickian moisture redistribution, particularly the separate evolution of bound- and free-water phases during decay. Here, we present a transport-response bio-hygrothermal finite element model that couples boundary-driven Monod-type fungal colonization kinetics with multi-phase moisture transport (free water, bound water, vapor) in decaying wood. Although fungal biomass evolution is simulated via a reaction–diffusion equation, decay progression is not derived from biomass–substrate interaction but prescribed independently as an experimentally informed input. The model incorporates decay-modified sorption isotherms, permeability evolution, and boundary-driven biomass influx, along with associated moisture transport, into the governing equations. The model is validated against low-field nuclear magnetic resonance (LF-NMR) measurements of C. puteana decay in Scots pine over 35 days. The model successfully reproduces the experimentally observed moisture evolution: a peak free-water content of 50%–70% during weeks 1–2, followed by a progressive decline, while bound water remains remarkably constant despite advancing decay. Monte Carlo uncertainty quantification demonstrates hierarchical parameter control: bound water is governed solely by thermodynamic factors, while free water responds to interacting biological and physical processes. Time-resolved correlation analysis shows a fundamental transition from colonization-dominated (weeks 1–2) to transport-dominated (weeks 3–5) moisture control, quantitatively explaining the experimentally observed shift from accumulation to depletion. This transport-response framework for analyzing moisture behavior under externally defined decay progression establishes quantitative parameter hierarchies that may inform the development of future substrate-coupled bio-hygrothermal models. Full article

The urban trade in non-timber forest products (NTFPs) plays a key role in sustaining livelihoods in the Global South, while also suggesting potential pressure on resource supply systems. This study provides an integrated analysis of NTFP diversity, market structure, economic importance, and perceived drivers of resource decline in Kolwezi, a rapidly expanding mining city where such dynamics remain poorly documented. Data were collected through surveys conducted with 35 sellers across two major urban markets and 384 consumers from different neighbourhoods and analysed using descriptive and inferential statistics to examine patterns, associations, and socio-demographic influences. A total of 65 NTFP species were recorded, including 49 plant, 14 animal, and 2 fungal species, reflecting strong dependence on Miombo ecosystems. Medicinal (59.3%) and food uses dominate, with multifunctional species such as Bobgunnia madagascariensis (Desv.) J.H.Kirkbr. & Wiersama, Canarium schweinfurthii Engl., Terminalia mollis M.A.Lawson, Gardenia ternifolia subsp. jovis-tonantis (Welw.) Verdc., and Albizia antunesiana Harms, playing a central role in both household use and market supply. The trade is largely female-dominated (79.1%) and constitutes a major component of the informal urban economy, with monthly incomes ranging from USD 9 to 429.3, primarily driven by sales volume rather than unit price. However, the sector is constrained by structural and logistical limitations, including remoteness of supply areas, seasonality, and limited value addition. The perceived declining availability of high-use-value species, attributed by respondents to deforestation, mining expansion, and overexploitation, highlights perceived sustainability concerns. These pressures are perceived differently across socio-demographic groups, indicating heterogeneous understandings of environmental change. Overall, the results indicate a perceived mismatch between rising urban demand and declining resource availability, which may reflect an emerging socio-ecological imbalance between urban demand and perceived resource availability. Addressing these challenges requires integrated strategies that combine the domestication of priority species, the development of processing chains, improved infrastructure, and strengthened governance mechanisms. Such approaches are essential to reconcile livelihood support with the sustainable management of NTFPs in rapidly transforming urban landscapes. Full article

Rapidly progressive infectious keratitis may involve the anterior uveal tract and lead to anterior segment inflammation, resulting in severe structural damage of the cornea and potentially causing corneal perforation or endophthalmitis if not promptly treated. We report the case of a 63-year-old male admitted to the Emergency Ophthalmology Department of the University Clinical Center in Katowice, Poland, with a rapidly progressive corneal ulcer of the left eye that had not responded to two weeks of outpatient topical antibiotic therapy. The condition developed after ocular trauma sustained while chopping wood. At presentation, visual acuity was limited to light perception with preserved projection. Multimodal imaging, including slit-lamp examination, anterior segment optical coherence tomography (AS-OCT), and in vivo confocal microscopy, revealed extensive corneal ulceration with severe stromal destruction, progressive corneal melting, and marked anterior segment inflammation, with an imminent risk of perforation. Microbiological cultures identified Pseudomonas aeruginosa. Despite intensive empiric topical antimicrobial therapy targeting both bacterial infection and a possible fungal component related to trauma with organic material, rapid clinical deterioration necessitated emergency therapeutic penetrating keratoplasty (PK). The procedure resulted in rapid resolution of inflammation and improvement in visual acuity, with best-corrected visual acuity (BCVA) reaching 0.3 logMAR during follow-up. At the three-month follow-up, the corneal graft remained clear with stable visual acuity and no recurrence of infection. The patient remains under regular long-term follow-up, with ongoing monitoring of graft clarity, intraocular pressure (IOP), and visual function. This case differs from routine presentations of infectious keratitis by demonstrating exceptionally rapid stromal melting despite promptly initiated empiric topical therapy. Multimodal imaging, particularly AS-OCT provided clinically meaningful information by revealing structural instability and an imminent risk of perforation not fully appreciable on slit-lamp examination, thereby supporting timely urgent keratoplasty. These findings highlight the practical diagnostic value of imaging-based assessment in advanced infectious keratitis and underscore its role in guiding surgical decision-making in eyes at high risk of corneal perforation. Full article

Histidine triad (HIT) family proteins contain a conserved histidine triad motif and play key roles in fungal metabolism and pathogenicity. This study focused on VD9136, a member of the HIT family in Verticillium dahliae, aiming to elucidate its biological function and mechanism underlying its role in cotton pathogenesis. A systematic investigation of the VD9136 gene in V. dahliae was conducted using bioinformatics analysis, gene knockout, genetic complementation, and pathogenicity assays. The results showed that VD9136 protein consists of 136 amino acids and is a stable, neutral, and weakly hydrophilic protein that lacks transmembrane domains and signal peptides; it is localized to the extracellular space via a non-classical secretion pathway. Its secondary structure is predominantly composed of α-helices and random coils. Phylogenetic analysis revealed that VD9136 is closely related to VliHIT, a homologous protein from V. longisporum, the pathogen responsible for Verticillium wilt in rapeseed. The promoter region of VD9136 contains multiple cis-acting elements, including light-responsive, hormone-responsive, and stress-responsive elements, indicating that its transcription may be regulated by multiple signaling pathways. VD9136 was significantly upregulated during the early stage of cotton infection (6–24 h post-inoculation). Pathogenicity assays demonstrated that V. dahliae knockout mutants lacking VD9136 exhibited a significant reduction in virulence, as evidenced by a lower disease index, decreased fungal biomass within plant tissues, and attenuated vascular browning in cotton plants. The pathogenic phenotype was successfully restored in genetic complementation strains. This study identified VD9136 as a key regulatory factor in the pathogenic process of V. dahliae, and its loss of function reduces the pathogenicity of V. dahliae. The findings provide a theoretical basis for elucidating the pathogenic mechanism of cotton Verticillium wilt and for developing corresponding prevention and control strategies. Full article

This study evaluates a SiO₂ nanoparticle (SiO₂NPs)/Paraloid B-72 nanocomposite as a restorative and antifungal treatment for deteriorated sandstone at the Ptolemaic Temple of Isis, located within a densely populated residential area. The temple stones exhibit structural damage, soiling, and severe microbiological deterioration. Fungal isolates from the sandstone were cultured on PDA medium and identified by ITS region DNA sequencing as Alternaria alternata, Penicillium chrysogenum, and Aspergillus niger. The SiO₂NPs and their Paraloid B-72 nanocomposites were synthesized and characterized using transmission electron microscopy (TEM) and X-ray diffraction (XRD). Stone samples, examined before and after treatment via SEM-EDX, TEM, and XRD, were used to assess both conservation performance and compatibility. Laboratory antifungal tests showed that SiO₂NPs at 300 ppm exhibited the greatest inhibition of mycelial growth, reaching 91.59% for P. chrysogenum, 90.77% for A. niger, and 85.2% for A. alternata. Mechanical testing demonstrated that treatment with the SiO₂NPs/Paraloid B-72 nanocomposite enhanced stone strength, increasing compressive strength from 26.5 MPa to 27.4 MPa. SEM images confirmed excellent, homogeneous dispersion of the nanocomposite on stone grains, forming a coherent coating without pore occlusion. Overall, the SiO₂NPs/Paraloid B-72 formulation improved sandstone surface properties while substantially improving short-term mechanical performance and antifungal efficacy, indicating promise for enhancing restoration procedures when combined with established conservation protocols for sandstone architectural heritage. Full article

Aspergillus flavus is a globally distributed filamentous fungus of major agricultural and medical importance, capable of producing carcinogenic aflatoxins and forming two specialized developmental structures, conidia and sclerotia. While the molecular framework governing conidiation has been well characterized in Aspergillus nidulans, the corresponding mechanisms in A. flavus remain somewhat unelucidated. In this study, we identified and functionally characterized AfldrnA, a gene encoding a basic helix–loop–helix (bHLH) transcription factor. Targeted deletion of AfldrnA resulted in an aconidial phenotype accompanied by a significant increase in sclerotia formation, whereas complementation with the intact AfldrnA gene restored conidiation and reduced sclerotia development. Phenotypic assays revealed that the ΔAfldrnA mutant exhibited normal vegetative growth, unchanged antifungal susceptibility, and unaffected aflatoxin B₁ production, indicating that AfldrnA primarily regulates developmental rather than metabolic differentiation. Additionally, observed differences between standard and dark incubation conditions suggest that AfldrnA may be involved in environmentally responsive regulation of fungal development. Overall, this study identifies AfldrnA as a pivotal transcriptional regulator essential for coordinating conidiation and sclerotia formation in A. flavus, providing new insights into the genetic and environmental regulation of fungal developmental programs. Full article

Brewer’s spent grain (BSG) is an abundant lignocellulosic by-product whose valorization can support circular bioeconomy strategies. This study evaluated BSG bioconversion by Aspergillus oryzae ATCC 10124 under solid-state fermentation (SSF) to produce lignocellulolytic enzymes and release second-generation (2G) sugars relevant to biorefinery applications. SSF was monitored over 0–10 days, and FPase, endo-cellulase, β-glucosidase, xylanase, mannanase, amylase, and ligninolytic enzyme activities were quantified. Enzymatic crude extracts were further assessed in SDS-PAGE analysis. Glucose, cellobiose, xylose and arabinose release and consumption were tracked throughout fermentation, and substrate transformation was supported by FTIR. The secretome exhibited a predominantly hydrolytic profile, with maximal hemicellulolytic and cellulolytic activity around days 2–4, as well as sustained amylase activity. Ligninolytic activity was not detected. Sugar profiles indicated rapid early hydrolysis of glucose, followed by progressive pentose release. The stabilization and decline were consistent with fungal uptake. Changes in the carbohydrate fingerprint and SDS–PAGE banding supported structural polysaccharide remodeling and hydrolytic protein secretion. Thus, this SSF platform confirmed certain potential for low-cost cellulolytic and hemicellulolytic enzyme generation. However, because sugar accumulation was temporary and followed by consumption, this system is best interpreted as a biological pretreatment and enzyme-generation step that supports subsequent downstream valorization. Full article