Search Results (5,013)

Arthrobotrys flagrans is a typical nematode-trapping fungus that captures nematodes by producing three-dimensional networks. FlbD is a DNA-binding protein containing a Myb domain, which plays a significant role in fungal development. However, the biological function of FlbD in nematode-trapping fungi remains unknown. In this study, we analyzed the physicochemical properties and conserved domains of AfFlbD and constructed the AfFlbD knockout strains (ΔAfFlbD) using homologous recombination. Our functional analysis revealed that the mutants produced more cottony aerial mycelia at the colony center. Additionally, the cell length of the mutants was reduced, indicating that AfFlbD regulates cell morphology in A. flagrans. Chemical stress tolerance assays of the mutants demonstrated reduced sensitivity to NaCl and sorbitol stresses but increased sensitivity to SDS and H₂O₂ stresses compared to the WT strain. Interestingly, the mutants spontaneously produced traps, and its pathogenicity to nematodes was significantly enhanced, suggesting that AfFlbD negatively regulates the pathogenicity of A. flagrans. Furthermore, the number of chlamydospores produced by the mutants was markedly reduced, though their morphology remained unchanged. Fluorescence localization analysis showed that AfFlbD localizes to the nuclei of chlamydospores, thereby regulating chlamydospore formation. This study provides important theoretical insights into the biological function of the FlbD transcription factor and offers new perspectives for the application of nematode-trapping fungi as a method of controlling plant-parasitic nematodes. Full article

One of the important traits of many plant growth-promoting rhizobacteria (PGPR) is the biocontrol of phytopathogens. Some PGPR metabolize phytohormone abscisic acid (ABA); however, the role of this trait in plant–microbe interactions is scarcely understood. Phytopathogenic fungi produce ABA and use this property as a negative regulator of plant resistance. Therefore, interactions between ABA-producing necrotrophic phytopathogen Botrytis sp. BA3 with ABA-metabolizing rhizobacterium Rhodococcus sp. P1Y were studied in a batch culture and in gnotobiotic hydroponics with sunflower seedlings. Rhizobacterium P1Y possessed no antifungal activity against BA3 and metabolized ABA, which was synthesized by BA3 in vitro and in associations with sunflower plants infected with this fungus. Inoculation with BA3 and the application of exogenous ABA increased the root ABA concentration and inhibited root and shoot growth, suggesting the involvement of this phytohormone in the pathogenesis process. Strain P1Y eliminated negative effects of BA3 and exogenous ABA on root ABA concentration and plant growth. Both microorganisms significantly modulated the hormonal status of plants, affecting indole-3-acetic, salicylic, jasmonic and gibberellic acids, as well as cytokinins concentrations in sunflower roots and/or shoots. The hormonal effects were complex and could be due to the production of phytohormones by microorganisms, changes in ABA concentrations and multiple levels of crosstalk in hormone networks regulating plant defense. The results suggest the counteraction of rhizobacteria to ABA-producing phytopathogenic fungi through the metabolism of fungal ABA. This expands our understanding of the mechanisms related to the biocontrol of phytopathogens by PGPR. Full article

Fusarium diseases are among the most dangerous fungal diseases of plants. To date, there are no plant protectants that completely prevent fusariosis. Current breeding trends are therefore focused on increasing genetic resistance. While global modern maize breeding relies on various molecular genetics techniques, they are useless without a precise characterization of genomic regions that determine plant physiological responses to fungi. The aim of this study was thus to characterize the expression of candidate genes that were previously reported by our team as harboring markers linked to fusarium resistance in maize. The plant material included one susceptible and four resistant varieties. Biotic stress was induced in adult plants by inoculation with fungal spores under controlled conditions. qRT-PCR was performed. The analysis focused on four genes that encode for GDSL esterase/lipase (LOC100273960), putrescine hydroxycinnamyltransferase (LOC103649226), peroxidase 72 (LOC100282124), and uncharacterized protein (LOC100501166). Their expression showed differences between analyzed time points and varieties, peaking at 6 hpi. The resistant varieties consistently showed higher levels of expression compared to the susceptible variety, indicating their stronger defense responses. Moreover, to better understand the function of these genes, their expression in various organs and tissues was also evaluated using publicly available transcriptomic data. Our results are consistent with literature reports that clearly indicate the involvement of these genes in the resistance response to fusarium. Thus, they further emphasize the high usefulness of the previously selected markers in breeding programs to select fusarium-resistant maize genotypes. Full article

Fungi contribute to ecosystem function through nutrient cycling and decomposition but may be affected by major disturbances such as fire. Some ecosystems are fire-adapted, such as prairies which require cyclical burning to mitigate woody plant encroachment and reduce litter. While fire suppresses fire-sensitive fungi, pyrophilous fungi may continue providing ecosystem functions. Using litter bags, we measured the litter decomposition at three prairies with unburned and burned sections, and we used Illumina sequencing to examine litter communities. We hypothesized that (H1) decomposition would be higher at unburned sites than burned, (H2) increased decomposition at unburned sites would be correlated with higher overall saprotroph diversity, with a lower diversity in autoclaved samples, and (H3) pyrophilous fungal diversity would be higher at burned sites and overall higher in autoclaved samples. H1 was not supported; decomposition was unaffected by burn treatments. H2 and H3 were somewhat supported; saprotroph diversity was lowest in autoclaved litter at burned sites, but pyrophilous fungal diversity was the highest. Pyrophilous fungal diversity significantly contributed to litter decomposition rates, while saprotroph diversity did not. Our findings indicate that fire-adapted prairies host a suite of pyrophilous saprotrophic fungi, and that these fungi play a primary role in litter decomposition post-fire when other fire-sensitive fungal saprotrophs are less abundant. Full article

This study explores the revival of cotton (Gossypium spp. L.) farming in Italy through sustainable practices, addressing economic and water-related challenges by integrating cultivar selection, arbuscular mycorrhizal fungi (AMF) inoculation, and deficit irrigation under organic farming. Field trials evaluated two widely grown Mediterranean cultivars (Armonia and ST-318) under three irrigation levels (I-100: 100% crop water requirement; I-70: 70%; I-30: 30%) across two Sicilian soil types (sandy loam vs. clay-rich). Under I-100, lint yields reached 0.99 t ha⁻¹, while severe deficit (I-30) yielded only 0.40 t ha⁻¹. However, moderate deficit (I-70) maintained 75–79% of full yields, proving a viable strategy. AMF inoculation significantly enhanced plant height (68.52 cm vs. 65.85 cm), boll number (+22.1%), and seed yield (+12.5%) (p < 0.001). Cultivar responses differed: Armonia performed better under water stress, while ST-318 thrived with full irrigation. Site 1, with higher organic matter, required 31–38% less water and achieved superior irrigation water productivity (1.43 kg m⁻³). Water stress also shortened phenological stages, allowing earlier harvests—important for avoiding autumn rains. These results highlight the potential of combining adaptive irrigation, resilient cultivars, and AMF to restore sustainable cotton production in the Mediterranean, emphasizing the importance of soil-specific management. Full article

Legumes are among the most important crops globally, serving as a major food source for protein and oil. In tropical regions, the cultivation of legumes has expanded significantly due to the increasing demand for food, plant-based products, and sustainable agriculture practices. However, tropical environments pose unique challenges, including high temperatures, erratic rainfall, soil infertility, and a high incidence of pests and diseases. Indeed, legumes are vulnerable to infections caused by bacteria, fungi, oomycetes, viruses, and nematodes. This review highlights the importance of legumes in tropical farming and discusses major diseases affecting productivity and their impact on the economy, environment, and lives of smallholder legume farmers. We emphasize the use of legume genetic resources and breeding, and biotechnology innovations to foster resistance and address the challenges posed by pathogens in legumes. However, an integrated approach that includes other cultivation techniques (e.g., crop rotation, rational fertilization, deep plowing) remains important for the prevention and control of diseases in legume crops. Finally, we highlight the contributions of plant genetic resources to smallholder resilience and food security. Full article

Ericoid mycorrhizal fungi (EMF) enhance plant fitness and metabolic regulations in nutrient-poor soils, though the mechanisms diving these interactions require further elucidation. This study investigated the physiological and metabolic responses of blueberry seedlings following 2- and 3-weeks inoculation with Oidiodendron maius H14. The results indicated that EMF could significantly increases plant biomass, improve the accumulation of osmoregulatory substances in leaves. Additionally, the colonization rate of EMF are 26.18% and 30.22% after 2- and 3-weeks, respectively. The Metabolomics analysis identified 758 (593 up- and 165 down-regulated) and 805 (577 up- and 228 down-regulated) differential metabolites in roots at 2- and 3-weeks inoculation with O. maius H14, respectively. KEGG pathway annotation revealed that O. maius H14 triggered various amino acid metabolism pathways, including tryptophan metabolism and arginine and proline metabolism. These findings suggested that O. maius H14 stimulated root-specific biosynthesis of growth-promoting compounds and antimicrobial compounds. Concomitant downregulation of stress-associated genes and upregulation of glutamine synthetase suggest EMF modulates host defense responses to facilitate symbiosis. Thus, our results demonstrated that O. maius H14 orchestrates a metabolic reprogramming in blueberry roots, enhancing growth and stress tolerance through coordinated changes in primary and specialized metabolism, which could inform strategies for improving symbiosis and metabolic engineering in horticultural practices. Full article

The genus Colletotrichum is widely known for its phytopathological significance, especially as the causative agent of anthracnose in diverse agricultural crops. However, recent studies have unveiled its ecological versatility and biotechnological potential, particularly among endophytic species. These fungi, which asymptomatically colonize plant tissues, stand out as high-yielding producers of bioactive secondary metabolites. Given their scientific and economic relevance, this review critically examines endophytic Colletotrichum species, focusing on the chemical diversity and biological activities of the metabolites they produce, including antibacterial, antifungal, and cytotoxic activity against cancer cells, and antioxidant properties. This integrative review was conducted through a structured search of scientific databases, from which 39 relevant studies were selected, highlighting the chemical and functional diversity of these compounds. The analyzed literature emphasizes their potential applications in pharmaceutical, agricultural, and industrial sectors. Collectively, these findings reinforce the promising biotechnological potential of Colletotrichum endophytes not only as sources of bioactive metabolites but also as agents involved in ecological regulation, plant health promotion, and sustainable production systems. Full article

The soil-borne fungi, Setophoma terrestris and Fusarium spp., are often associated with pink root, although the etiology of the disease remains doubtful. While recognized as the primary inoculum, studies show conflicting views on the formation of chlamydospores and microsclerotia in Setophoma. Therefore, this study aims to clarify the etiology of the pink root of garlic and onion and the formation of chlamydospores and microsclerotia in Setophoma. The isolates were obtained from symptomatic tissues of garlic, leeks, brachiaria, onions, chives, and maize collected from seven different states in Brazil. Representative isolates were selected for pathogenicity tests. Sequence comparison of the tubulin gene showed Setophoma (n = 50) and Fusarium clades (n = 25). Garlic and onion plants inoculated with Setophoma showed pink root symptoms, while plants inoculated with different Fusarium isolates remained asymptomatic. Multigene analysis of pathogenic isolates confirms that only Setophoma terrestris causes pink root in garlic and onion. In addition, brachiaria, chives, and leeks are newly identified hosts of this pathogen in Brazil. To our knowledge, the main sources of primary inoculum of the disease are chlamydospores, pycnidia, colonized roots of garlic, onion, and plant debris of susceptible crops. The new information obtained in this study will be fundamental for researchers in the development of genotypes that are resistant to pink root and will help the efficient management of the disease. Full article

The escalating global challenges of antimicrobial resistance (AMR) and cancer necessitate innovative therapeutic solutions from natural sources. This study investigated the multifaceted therapeutic potential of pigment-enriched plant extracts. We screened diverse plant extracts for antimicrobial and antibiofilm activity against multidrug-resistant bacteria and fungi. Hibiscus sabdariffa emerged as the most promising, demonstrating potent broad-spectrum antimicrobial and significant antibiofilm activity. Sub-inhibitory concentrations of H. sabdariffa robustly downregulated essential bacterial virulence genes and suppressed aflatoxin gene expression. Comprehensive chemical profiling via HPLC identified major anthocyanin glucosides, while GC-MS revealed diverse non-pigment bioactive compounds, including fatty acids and alcohols. Molecular docking suggested favorable interactions of key identified compounds (Cyanidin-3-O-glucoside and 1-Deoxy-d-arabitol) with E. coli outer membrane protein A (OmpA), indicating potential antiadhesive and antimicrobial mechanisms. Furthermore, H. sabdariffa exhibited selective cytotoxicity against MCF-7 breast cancer cells. These findings establish H. sabdariffa pigment-enriched extract as a highly promising, multi-functional source of novel therapeutics, highlighting its potential for simultaneously addressing drug resistance and cancer challenges through an integrated chemical, biological, and computational approach. Full article

Heavy metal pollution represents a pervasive environmental challenge that significantly exacerbates the ever-increasing crisis of antimicrobial resistance and the capacity of microorganisms to endure and proliferate despite antibiotic interventions. This review examines the intricate relationship between heavy metals and AMR, with an emphasis on the underlying molecular mechanisms and ecological ramifications. Common environmental metals, including arsenic, mercury, cadmium, and lead, exert substantial selective pressures on microbial communities. These induce oxidative stress and DNA damage, potentially leading to mutations that enhance antibiotic resistance. Key microbial responses include the overexpression of efflux pumps that expel both metals and antibiotics, production of detoxifying enzymes, and formation of protective biofilms, all of which contribute to the emergence of multidrug-resistant strains. In the soil environment, particularly the rhizosphere, heavy metals disrupt plant–microbe interactions by inhibiting beneficial organisms, such as rhizobacteria, mycorrhizal fungi, and actinomycetes, thereby impairing nutrient cycling and plant health. Nonetheless, certain microbial consortia can tolerate and detoxify heavy metals through sequestration and biotransformation, rendering them valuable for bioremediation. Advances in biotechnology, including gene editing and the development of engineered metal-resistant microbes, offer promising solutions for mitigating the spread of metal-driven AMR and restoring ecological balance. By understanding the interplay between metal pollution and microbial resistance, we can more effectively devise strategies for environmental protection and public health. Full article

This study evaluated the influence of compost and bioinoculants (mycorrhizal fungi and plant growth-promoting bacteria) on the yield and composition of essential oil extracted from Tanacetum balsamita L. over two growing seasons. The plants were cultivated under four treatments: compost, bioinoculants, a combination (bioinoculants + compost), and a control. At each harvest, essential oil was extracted from fresh leaves via stem-flow distillation and analyzed using gas chromatography coupled with single quadrupole mass spectrometry. Twenty to twenty-four compounds were identified. Based on the dominant terpene derivative, the results indicated that Tanacetum balsamita L. cultivated in Italy belongs to “camphor” chemotype, a pharmacologically active compound known for its antimicrobial, anti-inflammatory, and analgesic properties. Moreover, three compounds, α-, β-phellandrene and myrtenol, were identified as typical of Tanacetum balsamita L. cultivated in Italy. Treatment effects were significant for some compounds (camphor, borneol, terpinen-4-ol, α-terpineol, dehydro sabinene ketone, and 3-thujanol), and the interaction between treatment and year was significant for a few compounds (borneol, terpinen-4-ol, dehydro sabinene ketone, 1,8-cineol, and 3-thujanol). These results emphasize the need to account for seasonal variation and underline the necessity of a deeper understanding of how experimental factors interact with them, especially in long-term essential oil studies. Full article

Glycyrrhiza uralensis (G. uralensis), a leguminous plant, is an important medicinal and economic plant in saline–alkaline soils of arid regions in China. Its main bioactive components include liquiritin, glycyrrhizic acid, and flavonoids, which play significant roles in maintaining human health and preventing and adjuvantly treating related diseases. However, the cultivation of G. uralensis is easily restricted by adverse soil conditions in these regions, characterized by high salinity, high alkalinity, and nutrient deficiency. This study investigated the impacts of four multistrain microbial inoculants (Pa, Pb, Pc, Pd) on the growth performance and bioactive compound accumulation of G. uralensis in moderately saline–sodic soil. The aim was to screen the most beneficial inoculant from these strains, which were isolated from the rhizosphere of plants in moderately saline–alkaline soils of the Hexi Corridor and possess native advantages with excellent adaptability to arid environments. The results showed that inoculant Pc, comprising Pseudomonas silesiensis, Arthrobacter sp. GCG3, and Rhizobium sp. DG1, exhibited superior performance: it induced a 0.86-unit reduction in lateral root number relative to the control, while promoting significant increases in single-plant dry weight (101.70%), single-plant liquiritin (177.93%), single-plant glycyrrhizic acid (106.10%), and single-plant total flavonoids (107.64%). Application of the composite microbial inoculant Pc induced no significant changes in the pH and soluble salt content of G. uralensis rhizospheric soils. However, it promoted root utilization of soil organic matter and nitrate, while significantly increasing the contents of available potassium and available phosphorus in the rhizosphere. High-throughput sequencing revealed that Pc reorganized the rhizospheric microbial communities of G. uralensis, inducing pronounced shifts in the relative abundances of rhizospheric bacteria and fungi, leading to significant enrichment of target bacterial genera (Arthrobacter, Pseudomonas, Rhizobium), concomitant suppression of pathogenic fungi, and proliferation of beneficial fungi (Mortierella, Cladosporium). Correlation analyses showed that these microbial shifts were linked to improved plant nutrition and secondary metabolite biosynthesis. This study highlights Pc as a sustainable strategy to enhance G. uralensis yield and medicinal quality in saline–alkali ecosystems by mediating microbe–plant–nutrient interactions. Full article

Arbuscular mycorrhizal fungi (AMF) play a vital role in the restoration of tropical forests by enhancing soil fertility, facilitating plant establishment, and improving ecosystem resilience. This study presents a comprehensive bibliometric analysis of global scientific output on AMF in the context of ecological restoration, based on 3835 publications indexed in the Web of Science and Scopus databases from 2001 to 2024. An average annual growth rate of approximately 9.45% was observed, with contributions from 10,868 authors across 880 journals. The most prominent journals included Mycorrhiza (3.34%), New Phytologist (3.00%), and Applied Soil Ecology (2.79%). Thematically, dominant research areas encompassed soil–plant interactions, phytoremediation, biodiversity, and microbial ecology. Keyword co-occurrence analysis identified “arbuscular mycorrhizal fungi,” “diversity,” “soil,” and “plant growth” as core topics, while emerging topics such as rhizosphere interactions and responses to abiotic stress showed increasing prominence. Despite the expanding body of literature, key knowledge gaps remain, particularly concerning AMF–plant specificity, long-term restoration outcomes, and integration of microbial community dynamics. These findings offer critical insights into the development of AMF research and underscore its strategic importance in tropical forest restoration, providing a foundation for future studies and informing ecosystem management policies. Full article

Background: The typification of the name Aegilops tauschii Coss. (Poaceae: Triticeae) is revisited. Several authors cited a gathering from Iberia as the locality and Buxbaum as the collector of as the type, but no actual specimens from this collection have been located, nor is there evidence that such a gathering existed. In 1994, van Slageren designated as lectotype an illustration from Buxbaum’s Plantarum minus cognitarum centuria I (1728), which, although original material, is not the only element cited in the protologue. The protologue mentions several gatherings, some of which are represented by identifiable herbarium specimens qualifying as syntypes. Methods: This work is based on the analysis of the protologue of Aegilops tauschii and the study of specimens conserved in several herbaria. According to the International Code of Nomenclature for algae, fungi, and plants (ICN, Shenzhen Code 2018), an illustration does not hold the same nomenclatural weight as preserved specimens cited in the protologue. Therefore, van Slageren’s lectotypification does not comply with Art. 9.12 of the ICN and must be superseded. Results: The original material includes multiple elements, and a new lectotype is designated from a specimen at PRC from Azerbaijan. Full article