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To delve into the growth and physiological adaptations exhibited by the economically vital black wolfberry (Lycium ruthenicum) upon inoculation with arbuscular mycorrhizal fungi (AMF) under varying levels of saline–alkaline stress A series of pot experiments were conducted in a gradient saline–alkaline environment (0, 200, 400 mM NaCl: NaHCO3 = 1:1). One-year-old cuttings of black wolfberry, inoculated with two AMF species—Funneliformis mosseae (Fm) and Rhizophagus intraradices (Ri)—served as the experimental material, enabling a comprehensive analysis of seedling biomass, chlorophyll content, antioxidant enzyme activities, and other crucial physiological parameters. This study demonstrated that both Fm and Ri could form a symbiotic relationship with the root of Lycium ruthenicum. Notably, Fm inoculation significantly bolstered the growth of the underground parts, while exhibiting a remarkable capacity to scavenge reactive oxygen species (ROS), thereby effectively mitigating membrane oxidative damage induced by stress. Additionally, Fm promoted the accumulation of abscisic acid (ABA) in both leaves and roots, facilitating the exclusion of excess sodium ions from cells. Ri Inoculation primarily contributed to an enhancement in the chlorophyll b (Chlb) content, vital for sustaining photosynthesis processes. Furthermore, Ri's ability to enhance phosphorus (P) absorption under stressful conditions ensured a steady influx of essential nutrients. These findings point to different strategies employed for Fm and Ri inoculation. To holistically assess the saline–alkaline tolerance of each treatment group, a membership function analysis was employed, ultimately ranking the salt tolerance as Fm > Ri > non-mycorrhizal (NM) control. This finding holds paramount importance for the screening of highly resilient Lycium ruthenicum strains and offers invaluable theoretical underpinnings and technical guidance for the remediation of saline–alkaline soils, fostering sustainable agricultural practices in challenging environments. [ABSTRACT FROM AUTHOR]

Studying the membrane physiology of filamentous fungi is key to understanding their interactions with the environment and crucial for developing new therapeutic strategies for disease-causing pathogens. However, their plasma membrane has been inaccessible for a micron-sized patch-clamp pipette for pA current recordings due to the rigid chitinous cell wall. Here, we report the first femtosecond IR laser nanosurgery of the cell wall of the filamentous fungi, which enabled patch-clamp measurements on protoplasts released from hyphae. A reproducible and highly precise (diffraction-limited, submicron resolution) method for obtaining viable released protoplasts was developed. Protoplast release from the nanosurgery-generated incisions in the cell wall was achieved from different regions of the hyphae. The plasma membrane of the obtained protoplasts formed tight and high-resistance (GΩ) contacts with the recording pipette. The entire nanosurgical procedure followed by the patch-clamp technique could be completed in less than 1 hour. Compared to previous studies using heterologously expressed channels, this technique provides the opportunity to identify new ionic currents and to study the properties of the ion channels in the protoplasts of filamentous fungi in their native environment. [ABSTRACT FROM AUTHOR]

The regulation of fungal specialized metabolism is a complex process involving various regulators. Among these regulators, LaeA, a methyltransferase protein originally discovered in Aspergillus spp., plays a crucial role. Although the role of LaeA in specialized metabolism has been studied in different fungi, its function in Penicillium roqueforti remains unknown. In this study, we employed CRISPR-Cas9 technology to disrupt the laeA gene in P. roqueforti (PrlaeA) aiming to investigate its impact on the production of the specialized metabolites roquefortine C, mycophenolic acid, and andrastin A, as well as on asexual development, because they are processes that occur in the same temporal stages within the physiology of the fungus. Our results demonstrate a substantial reduction in the production of the three metabolites upon disruption of PrlaeA, suggesting a positive regulatory role of LaeA in their biosynthesis. These findings were further supported by qRT-PCR analysis, which revealed significant downregulation in the expression of genes associated with the biosynthetic gene clusters (BGCs) responsible for producing roquefortine C, mycophenolic acid, and andrastin A in the ΔPrlaeA strains compared with the wild-type P. roqueforti. Regarding asexual development, the disruption of PrlaeA led to a slight decrease in colony growth rate, while conidiation and conidial germination remained unaffected. Taken together, our results suggest that LaeA positively regulates the expression of the analyzed BGCs and the production of their corresponding metabolites in P. roqueforti, but it has little impact on asexual development. [ABSTRACT FROM AUTHOR]

Over evolutionary timescales, the logic and pattern of cell-type specific gene expression can remain constant, yet the molecular mechanisms underlying such regulation can drift between alternative forms. Here, we document a new example of this principle in the regulation of the haploid-specific genes in a small clade of fungal species. For most ascomycete fungal species, transcription of these genes is repressed in the a/α cell type by a heterodimer of two homeodomain proteins, Mata1 and Matα2. We show that in the species Lachancea kluyveri, most of the haploid-specific genes are regulated in this way, but repression of one haploid-specific gene (GPA1) requires, in addition to Mata1 and Matα2, a third regulatory protein, Mcm1. Model building, based on x-ray crystal structures of the three proteins, rationalizes the requirement for all three proteins: no single pair of the proteins is optimally arranged, and we show that no single pair can bring about repression. This case study exemplifies the idea that the energy of DNA binding can be "shared out" in different ways and can result in different DNA-binding solutions across different genes--while maintaining the same overall pattern of gene expression. [ABSTRACT FROM AUTHOR]

The article presents the results of monitoring the soil mycobiota of sulfur quarries in LvivRegion. The dynamics of soil micromycete complexes as a result of their adaptation to the conditions of technozems, embryozems and zonal soils of sulfur quarries was studied. The increase in the number of colony-forming units (CFU) in the studied soils of the Yavoriv and Podorozhnie sulfur quarries over the years is specified, which indicates the active processes of decomposition of plant remains, the formation of stable processes of decomposition of cellulose and other complex compounds in the detrital block of the ecosystem. The change in the frequency of banding of selected species of micromycetes over the years was studied, depending on the content of SO4-2 in the soil solution. The functional structure of soil micromycete communities after sulfur extraction was established. A decrease in the frequency of occurrence of pathogens and toxin-producing agents and an increase in the frequency of occurrence of species that actively participate in the transformation of organic remains, and also act as plant endophytes and participants in mycorrhizal symbiosis were recorded. The species composition of micromycetes that grew in the presence of SO4-2 content in the soil solution, which exceeded the background level from 3.6% to 50%, was determined, the species-bioindicators of soil pollution with sulfur compounds were defined - Fusarium oxysporum, Paecilomyces lilacinum, P. waksmanii, P. nigricans, P. funiculosum, Trichoderma viride, Cladosporium cladosporioides, C. herbarum, Aureobasidium pullulans, Humicola grisea, Ulocladium consortiale, Alternaria alternate, Mortierella ramanniana var. angulispora. During 10 years of research a decrease in the content of SO4-2 in soils was noted, which is associated with an increase in the biodiversity of soil micromycetes and an enrichment of the phytocenotic cover. [ABSTRACT FROM AUTHOR]

Filamentous fungi degrade complex plant material to its monomeric building blocks, which have many biotechnological applications. Transcription factors play a key role in plant biomass degradation, but little is known about their interactions in the regulation of polysaccharide degradation. Here, we deepened the knowledge about the storage polysaccharide regulators AmyR and InuR in Aspergillus niger. AmyR controls starch degradation, while InuR is involved in sucrose and inulin utilization. In our study, the phenotypes of A. niger parental, ΔamyR, ΔinuR and ΔamyRΔinuR strains were assessed in both solid and liquid media containing sucrose or inulin as carbon source to evaluate the roles of AmyR and InuR and the effect of culture conditions on their functions. In correlation with previous studies, our data showed that AmyR has a minor contribution to sucrose and inulin utilization when InuR is active. In contrast, growth profiles and transcriptomic data showed that the deletion of amyR in the ΔinuR background strain resulted in more pronounced growth reduction on both substrates, mainly evidenced by data originating from solid cultures. Overall, our results show that submerged cultures do not always reflect the role of transcription factors in the natural growth condition, which is better represented on solid substrates. Importance: The type of growth has critical implications in enzyme production by filamentous fungi, a process that is controlled by transcription factors. Submerged cultures are the preferred setups in laboratory and industry and are often used for studying the physiology of fungi. In this study, we showed that the genetic response of A. niger to starch and inulin was highly affected by the culture condition, since the transcriptomic response obtained in a liquid environment did not fully match the behavior of the fungus in a solid environment. These results have direct implications in enzyme production and would help industry choose the best approaches to produce specific CAZymes for industrial purposes. [ABSTRACT FROM AUTHOR]

Rust fungi (Pucciniales) are a diverse group of plant pathogens in natural and agricultural systems. They pose ongoing threats to the diversity of native flora and cause annual crop yield losses. Agricultural rusts are predominantly managed with fungicides and breeding for resistance, but new control strategies are needed on non‐agricultural plants and in fragile ecosystems. RNA interference (RNAi) induced by exogenous double‐stranded RNA (dsRNA) has promise as a sustainable approach for managing plant‐pathogenic fungi, including rust fungi. We investigated the mechanisms and impact of exogenous dsRNA on rust fungi through in vitro and whole‐plant assays using two species as models, Austropuccinia psidii (the cause of myrtle rust) and Coleosporium plumeriae (the cause of frangipani rust). In vitro, dsRNA either associates externally or is internalized by urediniospores during the early stages of germination. The impact of dsRNA on rust infection architecture was examined on artificial leaf surfaces. dsRNA targeting predicted essential genes significantly reduced germination and inhibited development of infection structures, namely appressoria and penetration pegs. Exogenous dsRNA sprayed onto 1‐year‐old trees significantly reduced myrtle rust symptoms. Furthermore, we used comparative genomics to assess the wide‐scale amenability of dsRNA to control rust fungi. We sequenced genomes of six species of rust fungi, including three new families (Araucariomyceaceae, Phragmidiaceae, and Skierkaceae) and identified key genes of the RNAi pathway across 15 species in eight families of Pucciniales. Together, these findings indicate that dsRNA targeting essential genes has potential for broad‐use management of rust fungi across natural and agricultural systems. [ABSTRACT FROM AUTHOR]

Global agriculture is frequently subjected to stresses from increased salt content, drought, heavy metals, and other factors, which limit plant growth and production, deteriorate soil health, and constitute a severe danger to global food security. Development of environmentally acceptable mitigation techniques against stresses and restrictions on the use of chemical fertilizers in agricultural fields is essential. Therefore, eco-friendly practises must be kept to prevent the detrimental impacts of stress on agricultural regions. The advanced metabolic machinery needed to handle this issue is not now existent in plants to deal against the stresses. Research has shown that the key role and mechanisms of arbuscular mycorrhiza fungi (AMF) to enhance plant nutrient uptake, immobilisation and translocation of heavy metals, and plant growth-promoting attributes may be suitable agents for plant growth under diversed stressed condition. The successful symbiosis and the functional relationship between the plant and AMF may build the protective regulatory mechansm against the key challenge in particular stress. AMF's compatibility with hyperaccumulator plants has also been supported by studies on gene regulation and theoretical arguments. In order to address this account, the present review included reducing the impacts of biotic and abiotic stress through AMF, the mechanisms of AMF to improve the host plant's capacity to endure stress, and the strategies employed by AM fungus to support plant survival in stressful conditions. [ABSTRACT FROM AUTHOR]

Background: Cotton is one of the most important cash crops in India. It is also called as "White gold" because of its agricultural as well as industrial importance. Myrothecium leaf blight is an emerging disease in cotton which is growing consistently throughout the country and has been reported to cause significant losses in major cotton growing tracts of odisha. Considering the importance of the disease, the present investigation has been taken up to study the physiology of the fungus. Methods: An experiment was conducted in vitro during 2016-18 to investigate the effect of temperature and pH on the growth of M. roridum. Seven different nutrient media viz. Potato Dextrose Agar (PDA) medium, Potato Sucrose Agar (PSA) medium, Host Leaf Extract Agar (HEA) medium, Potato Carrot Agar (PCA) medium, Czapek'sdox Agar (ZA) medium, Richard's Agar (RA) medium and Oat meal agar medium (OMA) were tested under in-vitro conditions to ascertain a suitable medium for the growth of M. roridum. Result: The investigation in laboratory conditions has revealed that out of seven nutrient media tested, maximum radial growth was recorded in Potato Sucrose Agar (PSA) with an average radial growth of diameter 76.06 mm and the least growth was recorded on Richard's Agar with a diameter of 23.66 mm. The growth of the fungus was observed to be maximum at a temperature of 28°C with a diameter of 61.09 mm and the minimum average growth of 17.36 mm was recorded at 36°C. Studies on pH revealed that that the fungus grows well in neutral and slight alkaline medium (6.5-8.0). [ABSTRACT FROM AUTHOR]

Purpose. This study aimed to compare predisposing factors, clinical characteristics, treatment, and prognosis of Fusarium keratitis according to the result of the initial potassium hydroxide (KOH) smear. Methods. This is a retrospective study of cases with Fusarium keratitis between January 2000 and December 2019 at two tertiary hospitals in South Korea. Patients were divided into two groups depending on the KOH smear result (KOH-positive and KOH-negative group), and its clinical factors were analyzed. Results. Among 319 fungal keratitis, seventy-nine cases were identified with Fusarium keratitis. Forty-seven cases (59.5%) were negative in the initial KOH smear prior to their diagnosis. The most common predisposing factor for Fusarium keratitis was ocular trauma (55.7%). There were no significant differences in sex, occupation, ulcer size or shape, hypopyon, and initial visual acuity between the two groups. Differences were observed between the KOH-positive group and the KOH-negative group in terms of deep corneal infiltration (50.0% vs. 78.7%, p = 0.008) and evisceration treatment (3.1% vs. 25.5%, p = 0.008). The delayed time to initiate antifungal eye drops was longer in the KOH-negative group (1.13 ± 0.49 vs. 3.93 ± 4.89, p = 0.002). Only the KOH-negative group combined bacterial infection. The significant risk factors for poor clinical outcomes were the central corneal lesion (odds ratio (OR) 3.50, p = 0.047), a large ulcer size (size ≥ 7.5 mm2) (OR 4.98, p = 0.009), and endothelial plaque (OR 7.00, p = 0.031). Conclusion. Initial KOH-negative patients often needed evisceration and had worse final visual outcomes. The delay of prompt initiation of antifungal treatment and combined bacterial infection result in a poor prognosis. This study highlights the initial KOH effect on early diagnosis and early treatment of Fusarium keratitis. [ABSTRACT FROM AUTHOR]

Fusarium is a phytopathogenic fungus involved in human pathology and is present in space stations. It is essential to understand the effects of microgravity on the physiology of this fungus to determine the potential risks to the health of crew members and to propose the necessary countermeasures. This study aimed to determine changes in the physiological parameters of the Fusarium solani species complex under simulated microgravity generated using a random positioning machine (RPM) and phenotypic approaches. We observed increased growth, spore production, and germination while biofilm production was reduced under RPM exposure. These in vitro data show the importance of further studying this fungus as it has been repeatedly demonstrated that microgravity weakens the immune system of astronauts. [ABSTRACT FROM AUTHOR]

Investigating the effects of microplastics remains a pertinent issue given the extensive biodiversity of exposed organisms, variations in the mechanisms of action among individual polymers, and their reliance on environmental conditions. Therefore, the objective of the study was to investigate some interactions of the popular biodegradable plastic poly(butylene adipate-co-terephthalate) (PBAT) on some aspects of the physiology of filamentous fungi Trichoderma spp., integral components of the soil microbiome known for promoting plant growth and aiding in pollution remediation. In the two Trichoderma strains examined, a positive influence on fungal growth was observed in the presence of microplastics (MPs). The capability to degrade MPs with the involvement of cytochrome P450 monooxygenases was confirmed through the detection of terephthalic acid (TPA) in postculture extractions. Additionally, inhibition of degradative activity in the presence of MPs was observed for metolachlor (MET) and 2,4-dichlorophenoxyacetic acid (2,4-D). Moreover, biodegradation pathways with the involvement several dechlorinated or hydroxylated metabolites were proposed for examined compunds. Concentration-dependent shifts in oxidative stress enzymes activity and slight modifications in phospholipid profiles were noted for the tested PBAT concentrations. In summary, this study enhances our understanding of PBAT's impact on the physiology of filamentous fungal and their degradative capacities important for mitigating environmental pollution by xenobiotics and plastics. [Display omitted] • The toxicity of PBAT microparticles is concentration-dependent. • Fungi show varying levels of sensitivity in different culturing conditions. • Trichoderma sp. is capable of degrading PBAT. • The presence of PBAT can impact the herbicide degradation process. • Trichoderma sp. is able to absorb microplastic into cells. [ABSTRACT FROM AUTHOR]

In this paper, Lignosus rhinocerotis (Cooke) Ryvarden (L. rhinocerotis) cultivated in rice medium (LRR) and in sawdust medium (LRS) was harvested. Then, in terms of the LRR, LRS, and wild L. rhinocerotis (LRW), the total flavonoid contents, total polyphenol contents, total polysaccharide contents, and metabolites were detected; antioxidants of their aqueous extracts and anti-inflammatory of their polysaccharides were performed. In addition, the possible mechanism of the polysaccharides of L. rhinocerotis inhibiting lung damage was elucidated. The results showed that 32 compounds were characterized in L. rhinocerotis, including flavonoids, terpenoids, lignans, and steroids and there were 20 compounds in cultivated and wild L. rhinocerotis; LRR has the highest total polyphenol and flavonoid contents, as well as ABTS and DPPH scavenging capacity. The total polysaccharide contents and the FRAP scavenging capacity of wild L. rhinocerotis were higher than those of cultivated L. rhinocerotis. The inhibition of polysaccharides of LRW (PLRW) on LPS-induced MRC-5 damage was stronger than that of the polysaccharides from cultivated L. rhinocerotis. The PLRW may alleviate lung damage by inhibiting the NLRP3 pathway and thereby suppressing the inflammatory response. In summary, both cultivated and wild L. rhinocerotis are abundant in bioactive components and have antioxidant and anti-inflammatory activities. [ABSTRACT FROM AUTHOR]

Recent studies suggest that arbuscular mycorrhizal fungi (AMF) have the potential to improve the growth and yield of eggplant (Solanum melongena L.) under soil-based organic production systems. However, the application of AMF in organic soilless vegetable production in a greenhouse has not been well studied, creating an important knowledge gap. Therefore, two greenhouse experiments [Experiment 1 (E1) and Experiment 2 (E2)] were conducted to investigate the effect of AMF (Glomus spp.) on the growth, gaseous exchange, and yield of eggplant fertilized with various liquid organic fertilizers (OFs) and inorganic fertilizers (IFs) in a soilless greenhouse production system. The experiment was conducted in a split-plot design with four replications in which liquid OFs [OF1 (5N–1P–1K), OF2 (0N–5P–5K and 3N–3P–3K), OF3 (3N–1P–1K), OF4 (5N–1P–2K), OF5 (3.7N–2.7P–3.7K), and OF6 (3N–3P–5K)], and IFs [IF1 (6N–4P–4K) and IF2 (4N–0P–1K and 1N–3P–5K)] were randomized as main plot factor, and AMF [inoculated and uninoculated (control)] as a subplot factor. Results indicate that AMF inoculation had no significant effect on the growth, gaseous exchange, and yield parameters of eggplant. Among different OFs, the eggplant fertilized with OF6 resulted in a 4.3% and 3% reduction of leaf area compared with top-performing IF1 treatment in E1 and E2, respectively. Further, the OF6 treatment resulted in a 12% and 15% reduction in total yield per plant compared with IF1 in E1 and E2, respectively. The differences in plant gaseous exchange parameters were also nonsignificant for eggplants fertilized with different OF and IF treatments in both E1 and E2. These results conclude that Glomus spp. were not associated with a significant increase in the yield of eggplant in the soilless production system. However, OFs were performing similar to IFs in terms of growth and yield, which could be due to a higher nutrient availability of these OFs, which are highly useful for the production of eggplant in greenhouse soilless production systems. [ABSTRACT FROM AUTHOR]

The plant microbiome plays a crucial role in facilitating plant growth through enhancing nutrient cycling, acquisition and transport, as well as alleviating stresses induced by nutrient limitations. Despite its significance, the relative importance of common agronomic practices, such as nitrogenous fertilizer, in shaping the plant microbiome across different cultivars remains unclear. This study investigated the dynamics of bacterial and fungal communities in leaf, root, rhizosphere, and bulk soil in response to nitrogenous fertilizer across ten sorghum varieties, using 16S rRNA and ITS gene amplicon sequencing, respectively. Our results revealed that nitrogen addition had a greater impact on sorghum-associated microbial communities compared to cultivar. Nitrogen addition significantly reduced bacterial diversity in all compartments except for the root endophytes. However, N addition significantly increased fungal diversity in both rhizosphere and bulk soils, while significantly reducing fungal diversity in the root endophytes. Furthermore, N addition significantly altered the community composition of bacteria and fungi in all four compartments, while cultivars only affected the community composition of root endosphere bacteria and fungi. Network analysis revealed that fertilization significantly reduced microbial network complexity and increased fungal-related network complexity. Collectively, this study provides empirical evidence that sorghum-associated microbiomes are predominantly shaped by nitrogenous fertilizer rather than by cultivars, suggesting that consistent application of nitrogenous fertilizer will ultimately alter plant-associated microbiomes regardless of cultivar selection., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

An important host defence mechanism against pathogens is intracellular killing, which is achieved through phagocytosis, a cellular process for engulfing and neutralizing extracellular particles. Phagocytosis results in the formation of matured phagolysosomes, which are specialized compartments that provide a hostile environment and are considered the end point of the degradative pathway. However, all fungal pathogens studied to date have developed strategies to manipulate phagosomal function directly and also indirectly by redirecting phagosomes from the degradative pathway to a non-degradative pathway with the expulsion and even transfer of pathogens between cells. Here, using the major human fungal pathogens Aspergillus fumigatus, Candida albicans, Cryptococcus neoformans and Histoplasma capsulatum as examples, we discuss the processes involved in host phagosome-fungal pathogen interactions, with a focus on fungal evasion strategies. We also discuss recent approaches to targeting intraphagosomal pathogens, including the redirection of phagosomes towards degradative pathways for fungal pathogen eradication., (© 2024. Springer Nature Limited.)

Fungal mycelium networks are large scale biological networks along which nutrients, metabolites flow. Recently, we discovered a rich spectrum of electrical activity in mycelium networks, including action-potential spikes and trains of spikes. Reasoning by analogy with animals and plants, where travelling patterns of electrical activity perform integrative and communicative mechanisms, we speculated that waves of electrical activity transfer information in mycelium networks. Using a new discrete space-time model with emergent radial spanning-tree topology, hypothetically comparable mycelial morphology and physically comparable information transfer, we provide physical arguments for the use of such a model, and by considering growing mycelium network by analogy with growing network of matter in the cosmic web, we develop mathematical models and theoretical concepts to characterise the parameters of the information transfer., Competing Interests: Declaration of competing interest Authors declare no conflicting interests., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Environmental microorganisms commonly inhabit dense multispecies biofilms, fostering mutualistic relationships and co-evolution. However, the mechanisms underlying biofilm formation and microbial interactions within the Baijiu fermentation microecosystem remain poorly understood. Hence, the objective of this study was to investigate the composition, structure, and interactions of microorganisms residing in biofilms on environmental surfaces in Baijiu production. The results revealed a shift in the bacteria-fungi interaction network following fermentation, transitioning from a cooperative/symbiotic relationship to a competitive/antagonistic dynamic. Core microbiota within the biofilms comprised lactic acid bacteria (LAB), yeast, and filamentous fungi. From the environmental surface samples, we isolated two strains of LAB (Lactiplantibacillus pentosus EB27 and Pediococcus pentosaceus EB35) and one strain of yeast (Pichia kudriavzevii EF8), all displaying remarkable biofilm formation and fermentation potential. Co-culturing LAB and yeast demonstrated a superior capacity for dual-species biofilm formation compared to mono-species biofilms. The dual-species biofilm displayed a two-layer structure, with LAB in the lower layer and serving as the foundation for the yeast community in the upper layer. The upper layer exhibited a dense distribution of yeast, enhancing aerobic respiration. Metabolic activities in the dual-species biofilm, such as ABC transporter, oxidative phosphorylation, citric acid cycle, sulfur metabolism, glycine, serine, threonine metabolism, lysine degradation, and cysteine and methionine metabolism, showed significant alterations compared to LAB mono-species biofilms. Moreover, bacterial chemotaxis, starch, and sucrose metabolism in the dual-species biofilm exhibited distinct patterns from those observed in the yeast mono-species biofilm. This study demonstrated that a core microbiota with fermentation potential may exist in the form of a biofilm on the surface of a Baijiu brewing environment. These findings provide a novel strategy for employing synthetic stable microbiotas in the intelligent brewing of Baijiu., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The stereotypical tip growth of filamentous fungi supports their lifestyles and functions. It relies on the polarized remodeling and expansion of a protective elastic cell wall (CW) driven by large cytoplasmic turgor pressure. Remarkably, hyphal filament diameters and cell elongation rates can vary extensively among different fungi. To date, however, how fungal cell mechanics may be adapted to support these morphological diversities while ensuring surface integrity remains unknown. Here, we combined super-resolution imaging and deflation assays to measure local CW thickness, elasticity and turgor in a set of fungal species spread on the evolutionary tree that spans a large range in cell size and growth speeds. While CW elasticity exhibited dispersed values, presumably reflecting differences in CW composition, both thickness and turgor scaled in dose-dependence with cell diameter and growth speeds. Notably, larger cells exhibited thinner lateral CWs, and faster cells thinner apical CWs. Counterintuitively, turgor pressure was also inversely scaled with cell diameter and tip growth speed, challenging the idea that turgor is the primary factor dictating tip elongation rates. We propose that fast-growing cells with rapid CW turnover have evolved strategies based on a less turgid cytoplasm and thin walls to safeguard surface integrity and survival.

In recent years, research into the complex interactions and crosstalk between plants and their associated microbiota, collectively known as the plant microbiome has revealed the pivotal role of microbial communities for promoting plant growth and health. Plants have evolved intricate relationships with a diverse array of microorganisms inhabiting their roots, leaves, and other plant tissues. This microbiota mainly includes bacteria, archaea, fungi, protozoans, and viruses, forming a dynamic and interconnected network within and around the plant. Through mutualistic or cooperative interactions, these microbes contribute to various aspects of plant health and development. The direct mechanisms of the plant microbiome include the enhancement of plant growth and development through nutrient acquisition. Microbes have the ability to solubilize essential minerals, fix atmospheric nitrogen, and convert organic matter into accessible forms, thereby augmenting the nutrient pool available to the plant. Additionally, the microbiome helps plants to withstand biotic and abiotic stresses, such as pathogen attacks and adverse environmental conditions, by priming the plant's immune responses, antagonizing phytopathogens, and improving stress tolerance. Furthermore, the plant microbiome plays a vital role in phytohormone regulation, facilitating hormonal balance within the plant. This regulation influences various growth processes, including root development, flowering, and fruiting. Microbial communities can also produce secondary metabolites, which directly or indirectly promote plant growth, development, and health. Understanding the functional potential of the plant microbiome has led to innovative agricultural practices, such as microbiome-based biofertilizers and biopesticides, which harness the power of beneficial microorganisms to enhance crop yields while reducing the dependency on chemical inputs. In the present review, we discuss and highlight research gaps regarding the plant microbiome and how the plant microbiome can be used as a source of single and synthetic bioinoculants for plant growth and health., Competing Interests: Declaration of Competing Interest There is no conflict of interest for this review proposal among all authors., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Plants naturally harbor diverse microbiomes that can dramatically impact their health and productivity. However, it remains unclear how fungal microbiome diversity, especially in the phyllosphere, impacts intermicrobial interactions and consequent nonadditive effects on plant productivity. Combining manipulative experiments, field collections, culturing, microbiome sequencing, and synthetic consortia, we experimentally tested for the first time how foliar fungal community diversity impacts plant productivity. We inoculated morning glories (Ipomoea hederifolia L.) with 32 phyllosphere consortia of either low or high diversity or with single fungal taxa, and measured effects on plant productivity and allocation. We found the following: (1) nonadditive effects were pervasive with 56% of fungal consortia interacting synergistically or antagonistically to impact plant productivity, including some consortia capable of generating acute synergism (e.g. > 1000% increase in productivity above the additive expectation), (2) interactions among 'commensal' fungi were responsible for this nonadditivity in diverse consortia, (3) synergistic interactions were approximately four times stronger than antagonistic effects, (4) fungal diversity affected the magnitude but not frequency or direction of nonadditivity, and (5) diversity affected plant performance nonlinearly with the highest performance in low-diversity treatments. These findings highlight the importance of interpreting plant-microbiome interactions under a framework that incorporates intermicrobial interactions and nonadditive outcomes to understand natural complexity., (© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)

Nanoplastics pose a potential threat to a wide variety of aquatic organisms. Despite the awareness of this existing hazard, the impact of nanoplastics on natural fungal communities remains a research gap. In this study, five dominant fungi species, isolated from a stream ecosystem, were used to explore the effects of different nano-polystyrene (nano-PS) particles concentrations on a simulated fungal community. Specifically, the evaluation was conducted regarding the fungal growth, reproductivity, structural composition, and ecological function in leaf litter decomposition. A 15-day exposure experiment showed that 100 μg/L nano-PS significantly reduced the microcosm pH. The extracellular enzyme activities of β-glucosidase, leucine-aminopeptidase, and peroxidase were significantly promoted by nano-PS exposure for 5 days or 15 days. Total sporulation rate significantly decreased after the 15-day exposure to 1 and 100 μg/L nano-PS and significantly increased under 10 μg/L nano-PS. In contrast, nano-PS concentrations had no effects on fungal biomass. In addition, the reduced relative abundance of Geotrichum candidum lowered its contribution to leaf decomposition, resulting in a decreased litter decomposition rate of a 24.5-27.9 % after exposure. This suggests that 1-100 μg/L nano-PS inhibited leaf decomposition by inhibiting fungal reproduction and reducing the contribution of specific fungal species. In addition, the findings highlight the importance of exploring the potential mechanisms of the interaction between nanoplastics and fungal species., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Unraveling the mechanisms of home-field advantage (HFA) is essential to gain a complete understanding of litter decomposition processes. However, knowledge of the relationships between HFA effects and microbial communities is lacking. To examine HFA effects on litter decomposition, we identified the microbial communities and conducted a reciprocal transplant experiment, including all possible combinations of soil and litter, between sites at two elevations in cool-temperate forests. Soil origin, rather than HFA, was an important factor in controlling litter decomposition processes. Microbiome-wide association analyses identified litter fungi and bacteria specific to the source soil, which completely differed at a low taxonomic level between litter types. The relative abundance of these microbes specific to source soil was positively correlated with litter mass loss. The results indicated that the unique relationships between plant litter and soil microbes through plant-soil linkages drive litter decomposition processes. In the short term, soil disturbances resulting from land-use changes have the potential to disrupt the effect of soil origin and hinder the advancement of litter decomposition. These findings contribute to an understanding of HFA mechanisms and the impacts of land-use change on decomposition processes in forest ecosystems., (© 2024 The Author(s). New Phytologist © 2024 New Phytologist Foundation.)

Fungus-growing termites, like Odontotermes obesus, cultivate Termitomyces as their sole food source on fungus combs which are continuously maintained with foraged plant materials. This necessary augmentation also increases the threat of introducing non-specific fungi capable of displacing Termitomyces. The magnitude of this threat and how termites prevent the invasion of such fungi remain largely unknown. This study identifies these non-specific fungi by establishing the pan-mycobiota of O. obesus from the fungus comb and termite castes. Furthermore, to maximize the identification of such fungi, the mycobiota of the decaying stages of the unattended fungus comb were also assessed. The simultaneous assessment of the microbiota and the mycobiota of these stages identified possible interactions between the fungal and bacterial members of this community. Based on these findings, we propose possible interactions among the crop fungus Termitomyces, the weedy fungus Pseudoxylaria and some bacterial symbiotes. These possibilities were then tested with in vitro interaction assays which suggest that Termitomyces, Pseudoxylaria and certain potential bacterial symbiotes possess anti-fungal capabilities. We propose a multifactorial interaction model of these microbes, under the care of the termites, to explain how their interactions can maintain a predominantly Termitomyces monoculture., (© 2024. The Author(s).)

When a pathogen invades a plant, it encounters a diverse microbiota with some members contributing to the health and growth of the plant host. So far, the relevance of interactions between pathogens and the plant microbiota are poorly understood; however, new lines of evidence suggest that pathogens play an important role in shaping the microbiome of their host during invasion. This review aims to summarize recent findings that document changes in microbial community composition during the invasion of filamentous pathogens in plant tissues. We explore the known mechanisms of interaction between plant pathogens and the host microbiota that underlie these changes, particularly the pathogen-encoded traits that are produced to target specific microbes. Moreover, we discuss the limitations of current strategies and shed light on new perspectives to study the complex interaction networks between filamentous pathogens and the plant microbiome., (© 2024. The Author(s).)

Grassland aridification threatens biodiversity which supports ecosystem multifunctionality (EMF), but the relative roles of biota in maintaining EMF are poorly known. A new study in PLoS Biology finds complementarity of above- and belowground biodiversity and a trade-off between fungal and plant richness in driving EMF with aridity., Competing Interests: The author declares no competing interests., (Copyright: © 2024 Julie R. Deslippe. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Propagule dispersal is a crucial aspect of the survival and reproduction of sessile organisms, such as plants and fungi. As such, the colours of fleshy fruits serve as a visual cue for animal dispersers. However, little is known about how, or whether, specific traits of fungal fruiting bodies, such as colour or shape, attract animal dispersers, and additionally the identities of fungal dispersers are poorly understood. Globally, most truffle-like fungi are dull-coloured, subterranean, and likely have scents that are attractive to mammalian dispersers. In Aotearoa-New Zealand, however, brightly coloured truffle-like fungi that emerge from the forest floor have seemingly proliferated. This proliferation has prompted the hypothesis that they are adapted to dispersal by a bird-dominated fauna. In our study, we used the literature and citizen science data (GBIF) to explore whether colourful species occur at a higher proportion of the total truffle-like fungi flora in Aotearoa-New Zealand than elsewhere in the world. In addition, we tested for a relationship between biotic factors (avian frugivory and forest cover) and abiotic factors (precipitation, radiation, and temperature) and the prevalence of brightly coloured truffle-like fungi across the world. The most colourful truffle-like fungi are in three defined regions: Australia, South and Central America and the Caribbean, and Aotearoa-NZ. Potential dispersers and the environment both relate to the distribution of truffle-like fungi: we found that increasing levels of frugivory were associated with higher proportions of colourful truffle-like fungi. This finding provides new insights into drivers of certain fungal traits, and their interactions between birds and fungi. Unique ecosystems, such as Aotearoa-NZ's bird-dominated biota, provide fascinating opportunities to explore how plants and fungi interact with the sensory systems of animals., (© 2024. The Author(s).)

Grasslands are integral to maintaining biodiversity and key ecosystem services and are under threat from climate change. Plant and soil microbial diversity, and their interactions, support the provision of multiple ecosystem functions (multifunctionality). However, it remains virtually unknown whether plant and soil microbial diversity explain a unique portion of total variation or shared contributions to supporting multifunctionality across global grasslands. Here, we combine results from a global survey of 101 grasslands with a novel microcosm study, controlling for both plant and soil microbial diversity to identify their individual and interactive contribution to support multifunctionality under aridity and experimental drought. We found that plant and soil microbial diversity independently predict a unique portion of total variation in above- and belowground functioning, suggesting that both types of biodiversity complement each other. Interactions between plant and soil microbial diversity positively impacted multifunctionality including primary production and nutrient storage. Our findings were also climate context dependent, since soil fungal diversity was positively associated with multifunctionality in less arid regions, while plant diversity was strongly and positively linked to multifunctionality in more arid regions. Our results highlight the need to conserve both above- and belowground diversity to sustain grassland multifunctionality in a drier world and indicate climate change may shift the relative contribution of plant and soil biodiversity to multifunctionality across global grasslands., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Martins et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Predicting how multiple anthropogenic stressors affect natural ecosystems is a major challenge in ecology. Freshwater ecosystems are threatened worldwide by multiple co-occurring stressors, which can affect aquatic biodiversity, ecosystem functioning and human wellbeing. In stream ecosystems, aquatic fungi play a crucial role in global biogeochemical cycles and food web dynamics, therefore, assessing the functional consequences of fungal biodiversity loss under multiple stressors is crucial. Here, a microcosm approach was used to investigate the effects of multiple stressors (increased temperature and nutrients, drying, and biodiversity loss) on three ecosystem processes: organic matter decomposition, fungal reproduction, and fungal biomass accrual. Net effects of stressors were antagonistic for organic matter decomposition, but additive for fungal reproduction and biomass accrual. Net effects of biodiversity were mainly positive for all processes, even under stress, demonstrating that diversity assures the maintenance of ecosystem processes. Fungal species displayed distinct contributions to each ecosystem process. Furthermore, species with negligible contributions under control conditions changed their role under stress, either enhancing or impairing the communities' performance, emphasizing the importance of fungal species identity. Our study highlights that distinct fungal species have different sensitivities to environmental variability and have different influence on the overall performance of the community. Therefore, preserving high fungal diversity is crucial to maintain fungal species with key ecosystem functions within aquatic communities in face of environmental change., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Biological invasions are now seen as one of the main threats to the Antarctic ecosystem. An example of such an invasion is the recent colonization of the H. Arctowski Polish Antarctic Station area by the non-native grass Poa annua . This site was previously occupied only by native plants like the Antarctic hair grass Deschampsia antarctica . To adapt successfully to new conditions, plants interact with soil microorganisms, including fungi. The aim of this study was to determine how the newly introduced grass P. annua established an interaction with fungi compared to resident grass D. antarctica . We found that fungal diversity in D. antarctica roots was significantly higher compared with P. annua roots. D . antarctica managed a biodiverse microbiome because of its ability to recruit fungal biocontrol agents from the soil, thus maintaining a beneficial nature of the endophyte community. P . annua relied on a set of specific fungal taxa, which likely modulated its cold response, increasing its competitiveness in Antarctic conditions. Cultivated endophytic fungi displayed strong chitinolysis, pointing towards their role as phytopathogenic fungi, nematode, and insect antagonists. This is the first study to compare the root mycobiomes of both grass species by direct culture-independent techniques as well as culture-based methods.

Despite recent advances in understanding the role of microorganisms in plant holobiont metabolism, physiology, and fitness, several relevant questions are yet to be answered, with implications for ecology, evolution, and sustainable agriculture. This article explores some of these questions and discusses emerging research areas in plant microbiomes. Firstly, it emphasizes the need to move beyond taxonomic characterization towards understanding microbial functions within plant ecosystems. Secondly, controlling methodological biases and enhancing OMICS technologies' standardization is imperative for a deeper comprehension of plant-microbiota interactions. Furthermore, while plant microbiota research has primarily centred on bacteria and fungi, other microbial players such as archaea, viruses, and microeukaryotes have been largely overlooked. Emerging evidence highlights their presence and potential roles, underscoring the need for thorough assessments. Future research should aim to elucidate the ecological microbial interactions, their impact on plant performance, and how the plant context shapes microbial community dynamics. Finally, a discussion is provided on how the multiple layers of abiotic and biotic factors influencing the spatiotemporal dynamics of plant-microbiome systems require in-depth attention. Examples illustrate how synthetic communities and computational methods such as machine learning and artificial intelligence provide alternatives to tackle these challenges and analyse the plant holobiont as a complex system., (© 2024 The Author(s). Environmental Microbiology Reports published by John Wiley & Sons Ltd.)

Soil microbial traits and functions play a central role in soil organic carbon (SOC) dynamics. However, at the macroscale (regional to global) it is still unresolved whether (i) specific environmental attributes (e.g., climate, geology, soil types) or (ii) microbial community composition drive key microbial traits and functions directly. To address this knowledge gap, we used 33 grassland topsoils (0-10 cm) from a geoclimatic gradient in Chile. First, we incubated the soils for 1 week in favorable standardized conditions and quantified a wide range of soil microbial traits and functions such as microbial biomass carbon (MBC), enzyme kinetics, microbial respiration, growth rates as well as carbon use efficiency (CUE). Second, we characterized climatic and physicochemical properties as well as bacterial and fungal community composition of the soils. We then applied regression analysis to investigate how strongly the measured microbial traits and functions were linked with the environmental setting versus microbial community composition. We show that environmental attributes (predominantly the amount of soil organic matter) determined patterns of MBC along the gradient, which in turn explained microbial respiration and growth rates. However, respiration and growth normalized for MBC (i.e., specific respiration and growth) were more linked to microbial community composition than environmental attributes. Notably, both specific respiration and growth followed distinct trends and were related to different parts of the microbial community, which in turn resulted in strong effects on microbial CUE. We conclude that even at the macroscale, CUE is the result of physiologically decoupled aspects of microbial metabolism, which in turn is partially determined by microbial community composition. The environmental setting and microbial community composition affect different microbial traits and functions, and therefore both factors need to be considered in the context of macroscale SOC dynamics., (© 2024 The Author(s). Global Change Biology published by John Wiley & Sons Ltd.)

Atmospheric nitrogen (N) deposition has been substantially reduced due to declines in the reactive N emission in major regions of the world. Nevertheless, the impact of reduced N deposition on soil microbial communities and the mechanisms by which they are regulated remain largely unknown. Here, we examined the effects of N addition and cessation of N addition on plant and soil microbial communities through a 17-year field experiment in a temperate grassland. We found that extreme N input did not irreversibly disrupt the ecosystem, but ceasing high levels of N addition led to greater resilience in bacterial and fungal communities. Fungi exhibited diminished resilience compared to bacteria due to their heightened reliance on changes in plant communities. Neither bacterial nor fungal diversity fully recovered to their original states. Their sensitivity and resilience were mainly steered by toxic metal ions and soil pH differentially regulating on functional taxa. Specifically, beneficial symbiotic microbes such as N-fixing bacteria and arbuscular mycorrhizal fungi experienced detrimental effects from toxic metal ions and lower pH, hindering their recovery. The bacterial functional groups involved in carbon decomposition, and ericoid mycorrhizal and saprotrophic fungi were positively influenced by soil metals, and demonstrated gradual recovery. These findings could advance our mechanistic understanding of microbial community dynamics under ongoing global changes, thereby informing management strategies to mitigate the adverse effects of N enrichment on soil function., (© 2024 John Wiley & Sons Ltd.)

The Coleoptera Cerambycidae (longicorn beetles) use wood under different states (living healthy, freshly snapped, completely rot, etc.) in a species-specific manner for their larval diet. Larvae of some Cerambycidae groups have mycetomes, accessory organs associated with the midgut that harbor fungal symbiont cells. The symbionts are thought to improve nutrient conditions; however, this has yet to be shown experimentally. To deduce the evolutionary history of this symbiosis, we investigated the characteristics of the mycetomes in the larvae of longicorn beetles collected in Japan. Lepturinae, Necydalinae, and Spondylidinae are the only groups that possess mycetomes, and these three groups' mycetomes and corresponding fungal cells exhibit different characteristics between the groups. However, the phylogenetic relationship of symbiont yeasts does not coincide with that of the corresponding longicorn beetle species, suggesting they have not co-speciated. The imperfect vertical transmission of symbiont yeasts from female to offspring is a mechanism that could accommodate the host-symbiont phylogenetic incongruence. Some Lepturinae species secondarily lost mycetomes. The loss is associated with their diet choice, suggesting that different conditions between feeding habits could have allowed species to discard this organ. We found that symbiont fungi encapsulated in the mycetomes are dispensable for larval growth if sufficient nutrients are given, suggesting that the role of symbiotic fungi could be compensated by the food larvae take. Aegosoma sinicum is a longicorn beetle classified to the subfamily Prioninae, which does not possess mycetomes. However, this species contains a restricted selection of yeast species in the larval gut, suggesting that the symbiosis between longicorn beetles and yeasts emerged before acquiring the mycetomes.

Plants thrive in diverse environments, where root-microbe interactions play a pivotal role. Date palm (Phoenix dactylifera L.), with its genetic diversity and resilience, is an ideal model for studying microbial adaptation to different genotypes and stresses. This study aimed to analyze the bacterial and fungal communities associated with traditional date palm cultivars and the widely cultivated "Deglet Nour" were explored using metabarcoding approaches. The microbial diversity analysis identified a rich community with 13,189 bacterial and 6442 fungal Amplicon Sequence Variants (ASVs). Actinobacteriota, Proteobacteria, and Bacteroidota dominated bacterial communities, while Ascomycota dominated fungal communities. Analysis of the microbial community revealed the emergence of two distinct clusters correlating with specific date palm cultivars, but fungal communities showed higher sensitivity to date palm genotype variations compared to bacterial communities. The commercial cultivar "Deglet Nour" exhibited a unique microbial composition enriched in pathogenic fungal taxa, which was correlated with its genetic distance. Overall, our study contributes to understanding the complex interactions between date palm genotypes and soil microbiota, highlighting the genotype role in microbial community structure, particularly among fungi. These findings suggest correlations between date palm genotype, stress tolerance, and microbial assembly, with implications for plant health and resilience. Further research is needed to elucidate genotype-specific microbial interactions and their role in enhancing plant resilience to environmental stresses., (© 2024. The Author(s).)

Epithelial cells orchestrate immune responses against fungal pathogens. This review highlights advances in integrating epithelial cells in immune responses against inhaled molds and dimorphic fungi, and against Candida species that colonize mucosal surfaces. In the lung, epithelial cells respond to interleukin-1 (IL-1) and interferon signaling to regulate effector cell influx and fungal killing. In the alimentary and vulvovaginal tracts, epithelial cells modulate fungal commensalism, invasive growth, and local immune tone, in part by responding to damage caused by candidalysin, a C. albicans peptide toxin, and through IL-17-dependent release of antimicrobial peptides that contribute to Candida colonization resistance. Understanding fungal-epithelial interactions in mammalian models of disease is critical to predict vulnerabilities and to identify opportunities for immune-based strategies to treat fungal infections., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Fungi are key decomposers of deadwood, but the impact of anthropogenic changes in nutrients and temperature on fungal community and its consequences for wood microbial respiration are not well understood. Here, we examined how nitrogen and phosphorus additions (field experiment) and warming (laboratory experiment) together influence fungal composition and microbial respiration from decomposing wood of angiosperms and gymnosperms in a subtropical forest. Nutrient additions significantly increased wood microbial respiration via fungal composition, but effects varied with nutrient types and taxonomic groups. Specifically, phosphorus addition significantly increased wood microbial respiration (65%) through decreased acid phosphatase activity and increased abundance of fast-decaying fungi (e.g., white rot), while nitrogen addition marginally increased it (30%). Phosphorus addition caused a greater increase in microbial respiration in gymnosperms than in angiosperms (83.3% vs. 46.9%), which was associated with an increase in Basidiomycota:Ascomycota operational taxonomic unit abundance in gymnosperms but a decrease in angiosperms. The temperature dependencies of microbial respiration were remarkably constant across nutrient levels, consistent with metabolic scaling theory hypotheses. This is because there was no significant interaction between temperature and wood phosphorus availability or fungal composition, or the interaction among the three factors. Our results highlight the key role of tree identity in regulating nutrient response of wood microbial respiration through controlling fungal composition. Given that the range of angiosperm species may expand under climate warming and forest management, our data suggest that expansion will decrease nutrient effects on forest carbon cycling in forests previously dominated by gymnosperm species., (© 2024 The Ecological Society of America.)

Polymicrobial biofilms are among the leading causes of antimicrobial treatment failure. In these biofilms, bacterial and fungal pathogens interact synergistically at the interspecies, intraspecies, and interkingdom levels. Consequently, combating polymicrobial biofilms is substantially more difficult compared to single-species biofilms due to their distinct properties and the resulting potential variation in antimicrobial drug efficiency. In recent years, there has been an increased focus on developing alternative strategies for controlling polymicrobial biofilms formed by bacterial and fungal pathogens. Current approaches for controlling polymicrobial biofilms include monotherapy (using either natural or synthetic compounds), combination treatments, and nanomaterials. Here, a comprehensive review of different types of polymicrobial interactions between pathogenic bacterial species or bacteria and fungi is provided along with a discussion of their relevance. The mechanisms of action of individual compounds, combination treatments, and nanomaterials against polymicrobial biofilms are thoroughly explored. This review provides various future perspectives that can advance the strategies used to control polymicrobial biofilms and their likely modes of action. Since the majority of research on combating polymicrobial biofilms has been conducted in vitro, it would be an essential step in performing in vivo tests to determine the clinical effectiveness of different treatments against polymicrobial biofilms., (Copyright © 2024 Elsevier Ltd and International Society of Antimicrobial Chemotherapy. All rights reserved.)

Plants coexist with a diverse array of microorganisms, predominantly bacteria and fungi, in both natural and agricultural environments. While some microorganisms positively influence plant development and yield, others can cause harm to the host, leading to significant adverse impacts on the environment and the economy. Plant growth-promoting microorganisms (PGPM), including plant growth-promoting bacteria, arbuscular mycorrhizal fungus (AMF), and rhizobia, have been found to increase plant biomass production by synthesizing hormones, fixing nitrogen, and solubilizing phosphate and potassium. Numerous studies have contributed to unraveling the complex process of plant-microbe interactions in recent decades. In light of the increasing global challenges such as population growth, climate change, and resource scarcity, it has become imperative to explore the potential of plant-bacteria-fungi crosstalk in promoting sustainability. This review aims to bridge existing knowledge gaps, providing a roadmap for future research in this dynamic field by synthesizing current knowledge and identifying emerging trends., Competing Interests: Declaration of Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Climate warming is severely affecting high-latitude regions. In the Arctic tundra, it may lead to enhanced soil nutrient availability and interact with simultaneous changes in grazing pressure. It is presently unknown how these concurrently occurring global change drivers affect the root-associated fungal communities, particularly mycorrhizal fungi, and whether changes coincide with shifts in plant mycorrhizal types. We investigated changes in root-associated fungal communities and mycorrhizal types of the plant community in a 10-yr factorial experiment with warming, fertilisation and grazing exclusion in a Finnish tundra grassland. The strongest determinant of the root-associated fungal community was fertilisation, which consistently increased potential plant pathogen abundance and had contrasting effects on the different mycorrhizal fungal types, contingent on other treatments. Plant mycorrhizal types went through pronounced shifts, with warming favouring ecto- and ericoid mycorrhiza but not under fertilisation and grazing exclusion. Combination of all treatments resulted in dominance by arbuscular mycorrhizal plants. However, shifts in plant mycorrhizal types vs fungi were mostly but not always aligned in their magnitude and direction. Our results show that our ability to predict shifts in symbiotic and antagonistic fungal communities depend on simultaneous consideration of multiple global change factors that jointly alter plant and fungal communities., (© 2024 The Authors. New Phytologist © 2024 New Phytologist Foundation.)

Symbiotic interactions between fungi and bacteria range from positive to negative. They are ubiquitous in free-living as well as host-associated microbial communities worldwide. Yet, the impact of fungal-bacterial symbioses on the organization and dynamics of microbial communities is uncertain. There are two reasons for this uncertainty: (1) knowledge gaps in the understanding of the genetic mechanisms underpinning fungal-bacterial symbioses and (2) prevailing interpretations of ecological theory that favor antagonistic interactions as drivers stabilizing biological communities despite the existence of models emphasizing contributions of positive interactions. This review synthesizes information on fungal-bacterial symbioses common in the free-living microbial communities of the soil as well as in host-associated polymicrobial biofilms. The interdomain partnerships are considered in the context of the relevant community ecology models, which are discussed critically., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Premise: Whole-genome duplication (neopolyploidy) can instantly differentiate the phenotype of neopolyploids from their diploid progenitors. These phenotypic shifts in organs such as roots and leaves could also differentiate the way neopolyploids interact with microbial species. While some studies have addressed how specific microbial interactions are affected by neopolyploidy, we lack an understanding of how genome duplication affects the diversity and composition of microbial communities., Methods: We performed a common garden experiment with multiple clones of artificially synthesized autotetraploids and their ancestral diploids, derived from 13 genotypes of wild strawberry, Fragaria vesca. We sequenced epiphytic bacteria and fungi from roots and leaves and characterized microbial communities and leaf functional traits., Results: Autotetraploidy had no effect on bacterial alpha diversity of either organ, but it did have a genotype-dependent effect on the diversity of fungi on leaves. In contrast, autotetraploidy restructured the community composition of leaf bacteria and had a genotype-dependent effect on fungal community composition in both organs. The most differentially abundant bacterial taxon on leaves belonged to the Sphingomonas, while a member of the Trichoderma was the most differentially abundant fungal taxon on roots. Ploidy-induced change in leaf size was strongly correlated with a change in bacterial but not fungal leaf communities., Conclusions: Genome duplication can immediately alter aspects of the plant microbiome, but this effect varies by host genotype and bacterial and fungal community. Expanding these studies to wild settings where plants are exposed continuously to microbes are needed to confirm the patterns observed here., (© 2024 The Authors. American Journal of Botany published by Wiley Periodicals LLC on behalf of Botanical Society of America.)

Beneficial interactions between plants and rhizosphere fungi can enhance plant adaptability during drought stress. However, harnessing these interactions will require an in-depth understanding of the response of fungal community assembly to drought. Herein, by using different varieties of wheat plants, we analyzed the drought-induced changes in fungal community assembly in rhizosphere and bulk soil. We demonstrated that drought significantly altered the fungal communities, with the contribution of species richness to community beta diversity increased in both rhizosphere and bulk soil compartments during drought stress. The stochastic processes dominated fungal community assembly, but the relative importance of deterministic processes, mainly homogeneous selection, increased in the drought-stressed rhizosphere. Drought induced an increase in the relative abundance of generalists in the rhizosphere, as opposed to specialists, and the top 10 abundant taxa that enriched under drought conditions were predominantly generalists. Notably, the most abundant drought-enriched taxon in rhizosphere was a generalist, and the corresponding Chaetomium strain was found capable of improving root length and activating ABA signaling in wheat plants through culture-based experiment. Together, these findings provide evidence that host plants exert a strong influence on rhizospheric fungal community assembly during stress and suggest the fungal communities that have experienced drought have the potential to confer fitness advantages to the host plants., Importance: We have presented a framework to integrate the shifts in community assembly processes with plant-soil feedback during drought stress. We found that environmental filtering and host plant selection exert influence on the rhizospheric fungal community assembly, and the re-assembled community has great potential to alleviate plant drought stress. Our study proposes that future research should incorporate ecology with plant, microbiome, and molecular approaches to effectively harness the rhizospheric microbiome for enhancing the resilience of crop production to drought., Competing Interests: The authors declare no conflict of interest.

Pathogenic bacteria of the Acinetobacter genus pose a severe threat to human health worldwide due to their strong adaptability, tolerance, and antibiotic resistance. Most isolates of these bacteria harbor a type VI secretion system (T6SS) that allows them to outcompete co-residing microorganisms, but whether this system is involved in acquiring nutrients from preys remains less studied. In this study, we found that Ab25, a clinical isolate of Acinetobacter nosocomialis, utilizes a T6SS to kill taxonomically diverse microorganisms, including bacteria and fungi. The T6SS of Ab25 is constitutively expressed, and among the three predicted effectors, T6e1, a member of the RHS effector family, contributes the most for its antimicrobial activity. T6e1 undergoes self-cleavage, and a short carboxyl fragment with nuclease activity is sufficient to kill target cells via T6SS injection. Interestingly, strain Ab25 encodes an orphan VgrG protein, which when overexpressed blocks the firing of its T6SS. In niches such as dry plastic surfaces, the T6SS promotes prey microorganism-dependent survival of Ab25. These results reveal that A. nosocomialis employs T6SSs that are highly diverse in their regulation and effector composition to gain a competitive advantage in environments with scarce nutrient supply and competing microbes.IMPORTANCEThe type VI secretion system (T6SS) plays an important role in bacterial adaptation to environmental challenges. Members of the Acinetobacter genus, particularly A. baumannii and A. nosocomialis, are notorious for their multidrug resistance and their ability to survive in harsh environments. In contrast to A. baumannii , whose T6SS has been well-studied, few research works have focused on A. nosocomialis . In this study, we found that an A. nosocomialis strain utilizes a contitutively active T6SS to kill diverse microorganisms, including bacteria and fungi. Although T6SS structural proteins of A. nosocomialis are similar to those of A. baumannii , the effector repertoire differs greatly. Interestingly, the T6SS of the A. nosocomialis strain codes for an ophan VgrG protein, which blocks the firing of the system when overexpressed, suggesting the existence of a new regulatory mechanism for the T6SS. Importantly, although the T6SS does not provide an advantage when the bacterium is grown in nutrient-rich medium, it allows A. nosocomialis to survive better in dry surfaces that contain co-existing bacteria. Our results suggest that killing of co-residing microorganisms may increase the effectiveness of strategies designed to reduce the fitness of Acinetobacter bacteria by targeting their T6SS., Competing Interests: The authors declare no conflict of interest.

Microbial inoculation involves transplanting microorganisms from their natural habitat to new plants or soils to improve plant performance, and it is being increasingly used in agriculture and ecological restoration. However, microbial inoculants can invade and alter the composition of native microbial communities; thus, a comprehensive analysis is urgently needed to understand the overall impact of microbial inoculants on the biomass, diversity, structure and network complexity of native communities. Here we provide a meta-analysis of 335 studies revealing a positive effect of microbial inoculants on soil microbial biomass. This positive effect was weakened by environmental stress and enhanced by the use of fertilizers and native inoculants. Although microbial inoculants did not alter microbial diversity, they induced major changes in the structure and bacterial composition of soil microbial communities, reducing the complexity of bacterial networks and increasing network stability. Finally, higher initial levels of soil nutrients amplified the positive impact of microbial inoculants on fungal biomass, actinobacterial biomass, microbial biomass carbon and microbial biomass nitrogen. Together, our results highlight the positive effects of microbial inoculants on soil microbial biomass, emphasizing the benefits of native inoculants and the important regulatory roles of soil nutrient levels and environmental stress., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Strong disturbances may induce ecosystem transitions into new alternative states that sustain through plant-soil interactions, such as the transition of dwarf shrub-dominated into graminoid-dominated vegetation by herbivory in tundra. Little evidence exists on soil microbial communities in alternative states, and along the slow process of ecosystem return into the predisturbance state. We analysed vegetation, soil microbial communities and activities as well as soil physico-chemical properties in historical reindeer enclosures in northernmost Finland in the following plot types: control heaths in the surrounding tundra; graminoid-dominated; 'shifting'; and recovered dwarf shrub-dominated vegetation inside enclosures. Soil fungal communities followed changes in vegetation, whereas bacterial communities were more affected by soil physico-chemical properties. Graminoid plots were characterized by moulds, pathotrophs and dark septate endophytes. Ericoid mycorrhizal and saprotrophic fungi were typical for control and recovered plots. Soil microbial communities inside the enclosures showed historical contingency, as their spatial variation was high in recovered plots despite the vegetation being more homogeneous. Self-maintaining feedback loops between plant functional types, soil microbial communities, and carbon and nutrient mineralization act effectively to stabilize alternative vegetation states, but once predisturbance vegetation reestablishes itself, soil microbial communities and physico-chemical properties return back towards their predisturbance state., (© 2024 The Authors. New Phytologist © 2024 New Phytologist Foundation.)

The intimate relationships between plants and fungi provide an opportunity for the shuttling of viruses. Dai et al. recently discovered that a virus undergoes cross-kingdom transmission, and naturally spreads to both plant and fungal populations. This finding expands our understanding of viral host range, evolution, transmission, and disease management., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Field surveys conducted during 2021 and 2022 in Western Sicily, Italy, revealed the presence of common fig trees severely affected by trunk and crown root canker and bark cracking. Moreover, in conjunction with the symptomatic tissues, the same surveyed plants showed the presence of bark beetle holes and internal wood galleries. The predominant beetle Criphalus dilutus was previously reported attacking figs in Sicily. Phylogenetic analyses based on multilocus DNA data showed the presence of different fungal taxa associated with disease symptoms, including Botryosphaeria dothidea , Ceratocystis ficicola , Diaporthe foeniculina , Neocosmospora bostrycoides , N. perseae , and Neofusicoccum luteum . Pathogenicity tests conducted on potted fig plants showed that all the species were pathogenic to fig, with C. ficicola and Neocosmospora spp. as the most aggressive fungal species. Moreover, isolations conducted from the bodies of emerging adult insects recovered from disease samples confirmed the presence of C. ficicola and Neocosmospora spp., suggesting the potential involvement of C. dilutus in their dissemination., Competing Interests: The author(s) declare no conflict of interest.

Spore killers are meiotic drive elements that can block the development of sexual spores in fungi. In the maize ear rot and mycotoxinproducing fungus Fusarium verticillioides, a spore killer called SkK has been mapped to a 102-kb interval of chromosome V. Here, we show that a gene within this interval, SKC1, is required for SkK-mediated spore killing and meiotic drive. We also demonstrate that SKC1 is associated with at least 4 transcripts, 2 sense (sense-SKC1a and sense-SKC1b) and 2 antisense (antisense-SKC1a and antisense-SKC1b). Both antisense SKC1 transcripts lack obvious protein-coding sequences and thus appear to be noncoding RNAs. In contrast, sense-SKC1a is a protein-coding transcript that undergoes A-to-I editing to sense-SKC1b in sexual tissue. Translation of sense-SKC1a produces a 70-aminoacid protein (Skc1a), whereas the translation of sense-SKC1b produces an 84-amino-acid protein (Skc1b). Heterologous expression analysis of SKC1 transcripts shows that sense-SKC1a also undergoes A-to-I editing to sense-SKC1b during the Neurospora crassa sexual cycle. Sitedirected mutagenesis studies indicate that Skc1b is responsible for spore killing in Fusarium verticillioides and that it induces most meiotic cells to die in Neurospora crassa. Finally, we report that SKC1 homologs are present in over 20 Fusarium species. Overall, our results demonstrate that fungal meiotic drive elements like SKC1 can influence the outcome of meiosis by hijacking a cell's A-to-I editing machinery and that the involvement of A-to-I editing in a fungal meiotic drive system does not preclude its horizontal transfer to a distantly related species. [ABSTRACT FROM AUTHOR]