Search Results (295)

Understanding the soil fungal community in vineyards sheds light on the interactions between plants and their associated microorganisms. For example, identifying arbuscular mycorrhizal fungi (AMF), which are beneficial to grapevine growth, is a good indicator of soil health. In contrast, other fungi, such as the pathogen group, can be detrimental to vine growth. The present study aimed to characterize the soil fungal community and the fungal diversity present at six Mediterranean vineyards located in Burgos (Spain), delving into fungal functional guilds and focusing on AMF and pathogenic fungal groups. The fungal structure was investigated using DNA metabarcoding in three soil samples taken from each vineyard, and differences in the abundance of functional guilds were assessed. Similar soil fungal community structures were observed among soil sample repetitions within vineyards. In contrast, adjacent vineyards presented differences in their microbial composition. Saprophytes followed by pathogens were the dominant fungal functional guilds across all vineyards. However, no differences in the relative abundance of the different fungal functional groups were observed among sites. The vineyard with the highest relative abundance of AMF (0.5%) also had the lowest pathogen relative abundance from all the sites (29.76%). Also, sites presenting a high relative abundance of pathogens in soil (>35%) had a low relative abundance of AMF (<0.05%). Our results suggest that the fungal community is affected by the intrinsic properties of the soil and the characteristics of each vineyard’s microsite over the effect of the geographical proximity. In addition, to improve our understanding of the soil microbial ecology, we highlight the necessity of prospecting soil fungal analyses into functional groups, interpreting diversity results within taxonomic groups alongside the total abundance of target groups/species. Full article

Carnivorous plants survive in harsh habitats with limited nutrients and a low pH. Much focus has been placed on carnivorous trap evolution as the primary mechanism to increase nutrient acquisition through insect digestion. Soil microbiome, however, may also play a pertinent role in nutrient acquisition influencing plant vigor and overall success. Dionaea muscipula, commonly known as the Venus’ flytrap, is endemic to rims of the Carolina Bays located in southeast North Carolina and northeast South Carolina, where D. muscipula survives in nutrient poor soils with a vestigial root system. We utilized a combination of microscopy, plating, and metagenomics, to investigate the presence/absence of fungal partners that may contribute to success and vigor of D. muscipula in its native habitat in order to further conservation of this carnivorous plant. Results support that D. muscipula forms both mycorrhizal and fungal endophytic associations, most likely to aid nutrient uptake from otherwise nutrient-poor soils, as well as aid in stress defense. Several ectomycorrhizal, endophytic, and saprophytic fungal species were identified from the surrounding rhizosphere of D. muscipula roots presenting a first glimpse into fungal communities that may influence D. muscipula physiology and compose the microbiome of the Carolina Bays ecosystem. Full article

A comprehensive comparative analysis was conducted on the nucleotide and amino acid sequences of intact phiLM21-like prophages (phiLM21-LPhs), which currently represent the most prevalent prophages in Sinorhizobium meliloti—a symbiotic partner of Fabaceae plants. Remarkably, the nucleotide sequences of 25 phiLM21-LPhs, identified across 36 geographically dispersed S. meliloti strains, covered no more than 34% of the phiLM21 phage genome. All prophages were integrated into specific isoacceptor tRNA genes and carried a tyrosine-type integrase gene; however, this integration did not exhibit features of tRNA-dependent lysogeny. Only one-fifth of phiLM21-LPhs encoded the minimal set of regulators for lysogenic/lytic cycle transitions, while the remainder contained either uncharacterized regulatory elements or appeared to be undergoing genomic “anchoring” within the host bacterium. The phiLM21-LPhs harbored open reading frames (ORFs) of diverse origins (phage-derived, bacterial, and unknown), yet over half of these ORFs had undeterminable functions, representing genetic “dark matter”. The observed diversification of intact phiLM21-like prophages likely stems from recombination events involving both virulent/temperate phages and phylogenetically remote bacterial taxa. The evolutionary and biological significance of the substantial genetic “dark matter” within these prophages in soil saprophytic bacteria remains an unresolved question. Full article

Atherigona orientalis (Diptera: Muscidae) may be a neglected agricultural pest worldwide since the public generally regards it as a saprophytic and sanitary insect. In fact, A. orientalis can infest over 50 varieties of fruits and vegetables in 26 families listed as quarantine pests in several countries. Regrettably, there are few reports of this pest despite its prevalence in the pantropical regions of many countries. In this study, we reported the distributions, morphological, and biological characteristics, including the host ranges, developmental durations, color selections, and population dynamics changes of A. orientalis in Hunan Province. Currently, A. orientalis has been found in each prefectural and municipal city of Hunan Province, China. Additionally, 15 out of 20 host plants we collected were infested. The developmental durations of the egg, larva, and pupa of A. orientalis ranged from 2 to 3, 5 to 7, and 6 to 8 days, respectively. The results of color selections showed that A. orientalis adults tend to prefer green and yellow colors. Moreover, the population dynamics of A. orientalis in Changsha City showed that July and August were the population peaks throughout the year. Our research supplements valuable data of A. orientalis for pest management and subsequent studies. Full article

Fusarium oxysporum f. sp. cucumerium, a resilient saprophytic fungus, poses a significant risk to cucumber crops. The research investigated the suppressive impact of Bacillus velezensis dhm2 on this pathogen and the synergistic performance of its crude lipopeptide extract with synthetic fungicides. Strain dhm2 inhibited the pathogen by 52.27% in confrontation culture. Its fermentation supernatant showed peak activity at 4 h bacterial age and 60 h fermentation duration, while the crude lipopeptide extract had an EC₅₀ of 9.99 g L⁻¹. Among the six chemical fungicides, prochloraz exhibited the highest toxicity, with an EC₅₀ value of 0.03 μg mL⁻¹. In all mixed combinations of the crude lipopeptide extract and chemical fungicides, there existed synergistic mixing ratios, particularly with difenoconazole (volume ratio 7:3, synergistic ratio 5.88) and propiconazole (7:3, 3.41), as confirmed by Wadley tests. Pot experiments revealed that the combined use of the crude lipopeptide extract and difenoconazole controlled cucumber Fusarium wilt by 80.95%. The mixture showed the highest SOD (315.76 U g⁻¹ FW min⁻¹), POD (281.63 U g⁻¹ FW min⁻¹), and CAT (23.39 U g⁻¹ FW min⁻¹), with increases over single treatments. This study provides an eco-friendly strategy for managing cucumber wilt, advocating reduced fungicide use via synergistic formulations. Full article

Rhabditis (Rhabditella) axei is a predominantly free-living nematode commonly found in sewage systems and decomposing organic matter. While primarily saprophytic, it has been documented as an opportunistic pathogen in human urinary and gastrointestinal tracts. The Chinese red panda (Ailurus styani), a rare and protected species in China, has not previously been reported as a host for Rhabditis (Rhabditella) spp. infections. This study reports the first documented occurrence of R. axei in red panda feces, unambiguously confirmed through integrative taxonomic approaches combining morphological and molecular analyses. The nematodes exhibited key morphological features consistent with R. axei, including a cylindrical rhabditiform esophagus, sexually dimorphic tail structures, and diagnostic spicule morphology. Molecular analysis based on 18S-ITS-28S rDNA sequencing confirmed their identity, showing >99% sequence similarity to R. axei reference strains (GenBank: PP135624.1, PP135622.1). Phylogenetic reconstruction using 18S rDNA and ITS rDNA sequences placed the isolate within a well-supported R. axei clade, clearly distinguishing it from related species such as R. blumi and R. brassicae. The findings demonstrate the ecological plasticity of R. axei as a facultative parasite capable of infecting non-traditional hosts and further highlight potential zoonotic risks associated with environmental exposure in captive wildlife populations. Our results emphasize the indispensable role of molecular diagnostics in accurately distinguishing morphologically similar nematodes within the Rhabditidae family, while providing essential baseline data for health monitoring in both in situ and ex situ conservation programs for this endangered species. Full article

Fungi, from saprophytes to pathogens, face predictable daily fluctuations in light, temperature, humidity, and nutrient availability. To cope, they have evolved an internal circadian clock that confers a major adaptive advantage. This review critically synthesizes current knowledge on the molecular architecture and physiological relevance of fungal circadian systems, moving beyond the canonical Neurospora crassa model to explore the broader phylogenetic diversity of timekeeping mechanisms. We examine the core transcription-translation feedback loop (TTFL) centered on the FREQUENCY/WHITE COLLAR (FRQ/WCC) system and contrast it with divergent and non-canonical oscillators, including the metabolic rhythms of yeasts and the universally conserved peroxiredoxin (PRX) oxidation cycles. A central theme is the clock’s role in gating cellular defenses against oxidative, osmotic, and nutritional stress, enabling fungi to anticipate and withstand environmental insults through proactive regulation. We provide a detailed analysis of chrono-pathogenesis, where the circadian control of virulence factors aligns fungal attacks with windows of host vulnerability, with a focus on experimental evidence from pathogens like Botrytis cinerea, Fusarium oxysporum, and Magnaporthe oryzae. The review explores the downstream pathways—including transcriptional cascades, post-translational modifications, and epigenetic regulation—that translate temporal signals into physiological outputs such as developmental rhythms in conidiation and hyphal branching. Finally, we highlight critical knowledge gaps, particularly in understudied phyla like Basidiomycota, and discuss future research directions. This includes the exploration of novel clock architectures and the emerging, though speculative, hypothesis of “chrono-therapeutics”—interventions designed to disrupt fungal clocks—as a forward-looking concept for managing fungal infections. Full article

Background/Objectives: Within their host trees, mountain pine beetles (MPBs, Dendroctonus ponderosae) interact with many fungal species, each releasing a unique profile of volatile organic compounds (VOCs). The FVOCs released by the two primary symbionts of MPBs, Grosmannia clavigera and Ophiostoma montium, have been found to enhance MPB attraction in the field and laboratory studies. Opportunistic, saprophytic fungal species, such as Aspergillus sp. and Trichoderma atroviride, are also common in MPB galleries and can negatively impact MPB fitness. However, little is known about the FVOCs produced by these fungal species and how they may impact MPB feeding and attraction. Methods: To address this knowledge gap, we characterized the FVOC profile of T. atroviride, and performed bioassays to test the effects of its FVOCs on MPB attraction and feeding activity. Results: Our chemical analysis revealed several FVOCs from T. atroviride known to inhibit the growth of competing fungal species and impact subcortical-beetle attraction. Conclusions: From those FVOCs, we recommended four compounds—2-pentanone, 2-heptanone, 2-pentanol, and phenylethyl alcohol—for use in future field tests as anti-attraction lures for MPBs. In bioassays, we also observed strong MPB repellency from FVOCs released by T. atroviride, as well as the mild effects of FVOCs on MPB feeding activity. Our findings highlight the potential for these FVOCs to be utilized in the development of more effective MPB anti-attractant lures, which are crucial for the monitoring and management of low-density MPB populations. Full article

Fusarioid fungi, members of the Nectriaceae within the Hypocreales (Ascomycota), exhibit diverse ecological roles and possess complex phylogenetic relationships, including endophytic, saprophytic, and pathogenic lifestyles. Among them, the genera Fusarium and Neocosmospora are particularly significant in agriculture and medicine. However, the boundaries between their species remain taxonomically contentious. In this study, 22 representative isolates from plant, fungal, and insect hosts were subjected to a polyphasic taxonomic approach that integrated morphological characterization, multilocus phylogenetic analyses, and phylogenomic analysis based on 4,941 single-copy orthologous genes. Consequently, five new species (F. dracaenophilum, F. puerense, F. wenshanense, N. alboflava, and N. fungicola) were described, and F. qiannanense and N. solani were recorded from new host species. The resulting phylogenomic tree topology was highly congruent with the multilocus phylogeny, providing robust support for the taxonomic distinction between Fusarium and Neocosmospora. This study provides new insights into the taxonomy of fusarioid fungi and has important implications for plant disease management, biodiversity conservation, and the study of fungal evolution. Full article

Pleurotus citrinopileatus, a valuable edible fungus characterized by its distinctive light yellow coloration and saprophytic growth on elm wood, has garnered increasing scientific interest due to its diverse bioactive constituents. Among these, polysaccharides derived from P. citrinopileatus (PCPs) have received the most extensive research attention. This review summarizes recent advances in the chemical structure and biological activities of PCPs. Structurally, PCPs are primarily composed of repeating units such as →3)-α-D-Glcp-(1→ and →6)-α-D-Galp-(1→. Functionally, PCPs exhibit a range of bioactivities, including immunomodulatory, hypoglycemic, and antitumor effects. Furthermore, the underlying mechanisms associated with these biological activities are also explored. This review aims to provide a comprehensive reference for future studies and facilitate the development and application of PCPs as potential functional food ingredients or therapeutic agents. Full article

Laboratory confirmation of human leptospirosis relies on serological tests, with the microscopic agglutination test (MAT) as the reference. However, due to its complexity, there is a need for a simpler and more accessible diagnostic method. This study aimed to standardise and develop an IgM dot-blot test with a whole-cell antigen from saprophytic Leptospira biflexa serovar Patoc for diagnosing human leptospirosis. After checkerboard titration standardisation, IgM dot-blot was performed with paired serum samples from 124 MAT-confirmed leptospirosis cases and 143 serum samples from healthy and diseased individuals as the control group. Repeatability and reproducibility were also evaluated. An IgM dot-blot kit was then developed and compared to the Panbio^TM Leptospira IgM ELISA using 144 serum samples from patients with suspected leptospirosis. The IgM dot-blot showed a sensitivity of 58.1% and 96.0% when performed on acute and convalescent samples, respectively. Specificity was 94.4%. The repeatability and reproducibility of the IgM dot-blot showed 100% consistency. Comparison of IgM dot-blot and IgM ELISA showed almost perfect agreement, with a Kappa index of 0.81. The developed IgM dot-blot offers a robust alternative to existing methods, requiring minimal specialised equipment and fewer reagents than IgM ELISA. The good performance of this IgM dot-blot immunoassay makes it a promising tool for diagnosing human leptospirosis, potentially increasing diagnostic capacity, especially in places with limited resources. Full article

The increasing consumer demand for minimally processed foods (MPFs) has highlighted the need for innovative preservation methods that ensure both safety and quality. Among promising biocontrol tools, bacteriophages—viruses that selectively destroy bacteria—have gained significant attention. This review explores the dual role of bacteriophages in the food industry. On one hand, they offer a natural, highly specific, and environmentally friendly means of controlling both pathogenic and spoilage bacteria in MPFs, contributing to improved food safety, extended shelf life, and reduced reliance on antibiotics and chemical preservatives. Their use spans primary production, bio-sanitization, and biopreservation. On the other hand, phages pose significant risks in fermentation-based industries such as dairy, where they can disrupt starter cultures and impair production. This review also examines the regulatory, technological, and safety challenges involved in phage application, including concerns about antibiotic resistance gene transfer, the presence of endotoxins, and scale-up limitations. Ultimately, this paper argues that with proper strain selection and regulation, bacteriophages can become valuable allies in sustainable food systems, despite their potential drawbacks. The application of strictly virulent bacteriophages as part of “green biotechnology” could enhance food quality and improve consumer health safety. By implementing the “farm to fork” strategy, bacteriophages may contribute to the production of health-promoting and sustainable food. Full article

Alternaria is a large genus of fungi comprising approximately 400 species, currently classified into 29 sections. These fungi exhibit a cosmopolitan distribution, thriving in both natural and human-impacted environments with saprophytic, endophytic, and parasitic lifestyles. As part of our ongoing studies on fungi associated with wetland plants in the families Cyperaceae and Juncaceae across various regions of Iran, we isolated 21 fungal strains displaying morphological traits of Alternaria. Multigene phylogenetic analysis and morphological examination of eight selected strains confirmed their placement within Alternaria with strong support. These isolates formed a basal clade distinct from the 29 previously recognized sections and six monotypic lineages, leading to the establishment of a new section, Alternaria section Iraniana, to accommodate them. Furthermore, two monophyletic lineages within this section were identified, representing two new species, A. avrinica and A. iraniana, which are described and illustrated in this study. The new section is distinguished by long, semi-macronematous to macronematous conidiophores with multiple geniculate and sympodial proliferations, as well as solitary, non-beaked conidia that have only transverse eu-septa to pseudo-septa. The newly described species are differentiated based on conidiophore and conidial characteristics and nucleotide sequence comparisons of genomic regions. These results contribute to a better understanding of the distribution and host range of Alternaria species, while highlighting the importance of ongoing research into fungal taxonomy and biodiversity in Iran, a region rich in potential for the discovery of new fungal species. Full article

Sialidases are gradually entering various areas of human practice—in medicine and pharmacy, as antiviral, antitumor, diagnostic, and vaccine preparations; for the chemoenzymatic synthesis of regioselective sialoglycoconjugates; and for the structural analysis of sialoglycoproteins. Optimizing the synthesis conditions of these commercially important enzymes would be beneficial for enhancing their production and expanding potential applications. Since sialidase producers are often pathogenic microorganisms, the use of saprophytic bacteria could be an alternative to reduce the health risk when working with them. So far, the topic has not been widely discussed. By a single-factor optimization method, the most suitable fermentation conditions for achieving maximum sialidase production by the non-model strain Oerskovia paurometabola O129 were established. The dynamics of enzyme accumulation during the growth phases and the optimal physicochemical parameters for cultivation were determined (30 °C, pH 8.0, agitation at 200 rpm, for 28 h). The addition of various inducers and surfactants to improve enzyme yield was also investigated. The effect of surfactants on bacterial sialidase production was tested for the first time. Maximum enzyme production (98.3 U/mL), representing about a three-fold increase compared to non-optimized conditions, was obtained by culturing the strain under optimal conditions and by the synergistic action of glucomacropeptide and Tween 80. A new, simple, and cost-effective laboratory model for optimizing sialidase production by the saprophytic strain O. paurometabola O129 in submerged fermentation was proposed. Future work may involve scaling up the process and exploring genetic or metabolic enhancements for targeted biomedical and industrial applications. Full article