Search Results (763)

Brassicaceae-based bio-disinfestation is a promising non-chemical option to manage lettuce Fusarium wilt caused by Fusarium oxysporum f. sp. lactucae (FOLac), but evidence integrating pathogen suppression, residue chemistry, and soil microbiome response remains limited. We conducted a greenhouse mesocosm assay with naturally infested soil to compare biofumigation (uncovered soil) and biosolarization (plastic-covered soil for 40 days) using five Brassicaceae residues (Brassica carinata, B. juncea, B. napus, Sinapis alba and Raphanus sativus) applied at two field-equivalent doses. Biosolarization created a distinct disinfestation environment, increasing soil temperature by an average of 2.74 °C and shifting oxidation–reduction potential toward reducing conditions. This strategy consistently reduced culturable Fusarium populations, F. oxysporum-assigned colony-forming units (CFU) and lettuce wilt severity compared with uncovered biofumigation. The strongest disease suppression was observed under plastic-covered conditions, including the soil-only control, indicating that the covered microenvironment was a major driver of suppressiveness, while Brassicaceae residues modulated the magnitude and consistency of the response. Glucosinolate profiling revealed contrasting residue chemistries among species, providing a biochemical context for interpreting species-dependent effects. Shotgun metagenomics further showed that biosolarization and biofumigation produced distinct genus-level microbial community structures, with significant effects of strategy, timepoint and their interaction, and higher Shannon diversity under biosolarization. Overall, the integration of disease severity, culture-based inoculum quantification, physicochemical indicators, residue chemistry and metagenomics supports Brassicaceae-based biosolarization as a promising pre-plant approach for suppressing FOLac wilt in naturally infested soils, with the plastic-covered disinfestation environment emerging as the main driver of suppression and Brassicaceae residues modulating the response. Full article

Pseudomonas sp. MUP55, isolated from rainfall water in Western Australia, was characterized by polyphasic taxonomy and functional assays. Whole-genome and 16S rRNA phylogeny placed Pseudomonas sp. MUP55 in the Pseudomonas fluorescens species group. Massetolide A/D was identified as the leading candidate bioactive compound(s), consistent with its biosynthetic gene cluster, GNPS library matching, and loss of activity in regulatory mutants. The strain showed broad-spectrum antimicrobial activity against bacterial (Escherichia coli and Xanthomonas campestris) and fungal (Fusarium oxysporum and Rhizoctonia solani) plant pathogens. GacA regulates Massetolide production: a P58L mutation abolished synthesis and reduced biocontrol efficacy. Metabolomic and transcriptomic analysis of a ΔpvfC mutant revealed that the pvf cluster regulates specialized metabolism while also contributing to secreted growth-inhibitory activity. The pvf cluster differentially regulates dual siderophore systems and uncouples the co-regulated small RNAs rsmY and rsmZ in the Gac/Rsm cascade. Deletion of pvfC partially reduced the growth-inhibitory activity of Pseudomonas sp. MUP55 supernatants against bacterial pathogens, indicating that pvfC also influences secreted antimicrobial activity beyond its global regulatory role. These findings establish Pseudomonas sp. MUP55 as a taxonomically novel, mechanistically characterized biocontrol agent with potential for sustainable agriculture. Full article

Cannabis sativa L. is a multipurpose plant widely cultivated for fiber, food, medicinal products, and the production of bioactive compounds, including psychoactive cannabinoids. Fungal endophytes are a promising source of antimicrobial compounds used for biological control and sustainable crop production. However, the fungal endophytes associated with C. sativa have been poorly investigated, and their biological activities are still largely unexplored. Thus, this study aimed to identify fungal endophytes from C. sativa (marijuana and hemp biotypes) and to screen for their antagonistic activities against some plant pathogens. Based on ITS sequence analysis, a total of 103 fungal endophyte isolates (21 genera) were preliminarily identified from both biotypes, including 62 isolates (13 genera) from hemp and 41 isolates (nine genera) from marijuana. Fusarium was the dominant genus found in hemp (45%), while Nigrospora was the dominant genus isolated from marijuana (32%). Ten selected fungal endophytes were evaluated for in vitro antagonistic activity against four bacterial pathogens, Pectobacterium spp. (PC 01 and PC 02) and Ralstonia solanacearum (RA 01 and RA 02), and four fungal pathogens, Fusarium solani (FU 01), F. oxysporum (FU 02), and Sclerotium sp. (SC 01 and SC 02), all of which are causal agents of potato diseases. Among the tested fungal endophytes, Colletotrichum sp. (SLLC-M24) and Nigrospora sp. (SLLC-H15) exhibited the strongest antifungal activity against Fusarium spp. (FU 01 and FU 02), with inhibition rates ranging from 56 to 64%. In addition, Pestalotiopsis sp. (SLLC-H5) demonstrated effective antibacterial activity against all tested bacterial pathogens, producing inhibition zones ranging from 19 to 23 mm. This finding represents an important step toward discovering novel and promising endophytes associated with Cannabis and their biological control potential for utilization in sustainable agriculture. Full article

Salinity poses a major threat to sustainable agriculture and coastal ecosystems, resulting in a substantial loss of plant productivity and biodiversity. Although some coastal grass species exhibit natural adaptation to saline conditions, the physiological mechanisms underlying salt tolerance remain incompletely understood, particularly regarding the contribution of plant-associated microorganisms. In a previous study, a commercial cultivar of red fescue (Festuca rubra ssp. rubra cv. Rafael) was shown to be salt sensitive when grown hydroponically, whereas wild populations of F. rubra commonly occur in coastal salt marshes (possibly ssp. litoralis). We hypothesized that this difference in salt tolerance is partly associated with beneficial fungal plant interactions. To test this hypothesis, we investigated whether inoculation with a fungal isolate designated Fusarium sp. 1 and isolated from F. rubra growing on a salt marsh along the Dutch Wadden Sea coast could improve the salinity tolerance of the commercial cultivar. The results showed that inoculation with Fusarium sp. 1 alleviated the salt-induced growth inhibition. At 100 mM NaCl, shoot and root biomass were partially restored relative to non-inoculated controls, accompanied by a significant increase in the shoot-to-root ratio. To investigate the physiological basis of this response, we applied the Microelectrode Ion Flux Estimation (MIFE) technique to quantify Na⁺ -induced K⁺ efflux in roots. Inoculated plants exhibited improved K⁺ homeostasis, characterized by a reduced instantaneous Na⁺-induced K⁺ efflux and a faster recovery of root fluxes. Moreover, inoculated plants grown at 50 and 100 mM NaCl displayed 333% and 397% greater net K⁺ influx, respectively, compared with non-inoculated controls. Our results indicated that inoculation with Fusarium sp. 1 improves the salinity tolerance of F. rubra, likely through enhanced root K⁺ retention. These findings suggest that commercial F. rubra cultivars remain responsive to beneficial microbial associations and highlight the potential of exploring plant–microbe interactions from naturally salt-adapted environments to improve salinity resilience in grasses and potentially other crops. Full article

Fusarium oxysporum f. sp. radicis-cucumerinum (Forc) V03-2g and Fusarium oxysporum f. sp. radicis-lycopersici (Forl) ZUM2407 both cause foot and root rot in cucumber, but differ in host range. Forc V03-2g possesses Secreted in Xylem (SIX) effector genes, whereas Forl ZUM2407 does not, raising questions about their distinct infection strategies on this host. Using comparative transcriptomic analysis (in cucumber at 7 and 14 days post-inoculation (dpi) and in tomato at 2 dpi) we show that Forl ZUM2407 induces a delayed defense response in cucumber compared to Forc V03-2g. In turn, Forc V03-2g rapidly activates accessory chromosome effectors on cucumber, while Forl ZUM2407 initially deploys core chromosome genes, activating distinct from Forc V03-2g accessory genes only by 14 dpi. Thereby, Forc V03-2g and Forl ZUM2407 use distinct accessory gene repertoires (unique to each strain) and distinct core gene transcription strategies to infect the same host. Full article

Fusarium wilt, caused by Fusarium oxysporum f. sp. melonis (FOM), is a main disease of melon (Cucumis melo L.). FOM 1.2 is the most widespread and detrimental variant of FOM, causing substantial economic losses under severe disease conditions. Current information suggests that resistance to race 1.2 (FOM 1.2) is controlled by multiple recessive genes and is strongly influenced by the environment. Therefore, identifying genetic polymorphisms within diverse melon populations is essential to elucidate the loci and putative candidate genes associated with resistance. The objective of this investigation was to identify single-nucleotide polymorphism (SNP) and structural variant (SV) markers associated with FOM 1.2 resistance utilizing a panel of 160 genotypes through a genome-wide association study (GWAS). Phenotypic evaluation was performed two weeks after sowing, at the first-true-leaf stage, on 2400 individual plants inoculated by the root dip method with a concentration of about 10⁶ spores/mL. Biochemical and disease-related traits, including area under disease progress curve (AUDPC), disease severity index (DSI), standardized AUDPC (SAUDPC), latent period (LP), catalase, peroxidase activity, and ascorbate peroxidase activity were measured 35 days after inoculation. PCA identified eighty-three individual melon plants with a broad range of disease-response variation. Genotyping-by-sequencing (GBS) was conducted on these plants, resulting in the identification of 737,435 SNPs and 75,133 SVs. Evaluation of the population structure outlined four genetic groups, including one associated with germplasm highly resistant to FOM 1.2. We used SNP data to describe linkage disequilibrium (LD), which was estimated to decay at 14 kb, on average. A GWAS was performed using the Bayesian information and linkage-disequilibrium iteratively nested keyway (BLINK) method, which revealed nine SNPs significantly associated with several disease indices, namely ascorbate peroxidase activity, AUDPC, catalase, peroxidase activity, rAUDPC, and SAUDPC. Also, eight SVs were associated with AUDPC and relative area under disease progress curve (rAUDPC), including translocation and deletion types. In addition, GWAS using the fixed and random model circulating probability unification (FarmCPU) method unveiled thirteen SVs associated with rAUDPC, peroxidase activity and ascorbate peroxidase activity, including translocation and inversion types. According to the performed models of GWAS, several significant SNPs and SVs, associated with putative candidate genes, including multidrug resistance-associated protein 6 (MRP6), LOB domain-containing protein 15 (LBD15), phosphomannomutase, and NADH-ubiquinone oxidoreductase B8 subunit, which may be involved in FOM 1.2 resistance. However, these findings represent a preliminary genome-wide survey and require further validation using high-coverage or long-read sequencing approaches. The results provide remarkable insights into the genetic control of FOM 1.2 resistance and valuable information for the implementation of the putative molecular markers identified in this study in melon breeding programs. Full article

Maintaining food systems in the face of climate change (CC) is a major concern. Palm oil is included in many commodities, and oil palms (OPs) will be adversely affected by an inclement future climate, which could cause OPs to experience increases in disease incidence, higher mortality and a decline in growth. Basal stem rot, bud rot and Fusarium wilt of the OP are considered in the present paper, as attempts to control these diseases have been unsuccessful. A new approach may be the replacement of compromised OPs with different crops better suited to the future climate and which may exhibit fewer diseases initially because of the “parasites lost” phenomenon. Maintaining a vegetable oil product is an important advantage of this approach. How CC will affect OPs has been determined previously by CLIMEX modelling. The modelling of a future suitable climate has also been carried out for soybeans, maize and the common bean using the same modelling parameters. This enables direct comparisons with the OP production in countries such as Colombia, Nigeria and Papua New Guinea. Limited data for rapeseed are also available. The results show that the suitability of future suitable climate for OPs was much reduced in these countries and that for soybeans remained beneficial. Under these conditions, soybeans may exhibit fewer diseases, as they would be an introduced and annual crop. Maize exhibited far fewer advantages, and the common bean and rapeseed showed none. Maize exhibited potential advantages in Nigeria until 2050. A novel method for adapting to the serious diseases, poor growth and mortality of OPs would be to grow soybeans in regions similar to those in which OPs currently grow, but for which modelling suggests that their health will become limited. Plans, which could be modified when real-time data become available, could be made for replacing OPs with soybeans. This current paper provides a novel method for mitigating the future diseases, poor growth and mortality of OPs whilst maintaining valuable oil production. Full article

Fusarium oxysporum f. sp. lycopersici (Fol) is a destructive soil-borne pathogen responsible for major global losses in tomato production, within a context of increasingly constrained fungicide use in intensive farming systems. Sustainable alternatives to chemical fungicides are urgently needed, and microbial secondary metabolites represent a promising source of antifungal compounds. This study explores the antifungal potential of secondary metabolites produced by a natural isolate of Beauveria bassiana (Bb758) previously reported to exhibit strong biocontrol activity against Fol. LC-HRMS metabolomic profiling revealed a chemically diverse metabolite profile dominated by amino acid-derived compounds, peptides and alkaloids. Purification of the crude extract by column chromatography and reverse-phase HPLC yielded beauvericin and several 2,5-diketopiperazines as the main bioactive constituents. These compounds were identified by NMR and LC-HRMS analyses. The antifungal activity of beauvericin (BEA), cyclo(l-Phe-l-Pro) (CFP) and fractions was evaluated against spore germination and germ tube development of Fol. BEA exhibited dose-dependent but limited activity, showing significant inhibition only at high concentrations (100 μg mL⁻¹). In contrast, CFP showed significantly higher antifungal activity than BEA, inhibiting both germination and germ tube formation at concentrations as low as 10 μg mL⁻¹. These results identify CFP as a promising antifungal compound targeting the early infection stages of Fol and highlight fungal-derived diketopiperazines as candidate molecules for sustainable disease management strategies. Full article

This research evaluated the biocontrol potential of the bacterial flora from cured sugarcane bagasse (SCB) against Fusarium oxysporum f. sp. lycopersici (Fol), the causal agent of tomato Fusarium wilt. Screenings of twenty SCB-derived isolates revealed consistent antagonistic activity, inhibiting mycelial growth from 32.08% to 55.00%. The most effective isolate, 100MTN1, was identified via 16S rRNA sequencing (GenBank: PX506225) as Bacillus atrophaeus. Interaction between B. atrophaeus 100MTN1 and Fol FOLViF has revealed a distinct profile of bioactive metabolites produced specifically during co-cultivation. Transcriptomic profiling of Fol FOLViF exposure to 100MTN1 identified 189 differentially expressed genes, with downregulation of genes involved in DNA replication, translation, and membrane transport, and upregulation of those linked to secondary metabolism and oxidative stress. KEGG pathway mapping further supported the possible causes of disruptions within the pathogen. Molecular docking suggested that the B. atrophaeus 100MTN1 derived metabolite, 6-Hydroxy-3′-methoxyflavone and exhibits binding affinity for key Fol proteins that compares favorably with the commercial fungicides. Greenhouse trials using tomato cv. Kalyan confirmed that treatment with strain 100MTN1 was associated with reduced disease severity and enhanced plant growth. These findings suggest that B. atrophaeus 100MTN1 suppresses Fol FOLViF through a combination of metabolite-driven inhibition and transcriptional interference, signifying its potential as a biological control agent for managing Fusarium wilt. Full article

Polygonatum cyrtonema (P. cyrtonema) Hua is an important economic crop with both edible and medicinal value. However, frequent root rot severely restricts its industrial development, resulting in sharp yield reduction and quality deterioration. To clarify the primary pathogenic fungi causing root rot of P. cyrtonema Hua, 58 fungal strains from naturally diseased P. cyrtonema Hua plants in different habitats were isolated in this study. By combining morphological observation and molecular identification based on 18S rDNA and ITS rDNA sequences, the species of 22 pathogenic fungi were identified, among which 10 strains belonged to the genus Fusarium, accounting for 45.45% of the identified isolates. The pathogenicity of 21 pathogenic fungi was verified according to Koch’s postulates, with findings indicating that Fusarium species exhibited significant pathogenic potential. Meanwhile, six previously identified endophytic Paenibacillus strains isolated from P. cyrtonema Hua were employed to perform dual culture assays and antifungal evaluations of their fermentation supernatants against representative strains including F. concentricum F2, Neopestalotiopsis sp. F3 and F. oxysporum F8. The results indicated that the antagonistic activity exhibited by the six strains exceeded 50%, with the inhibition rates of their fermentation supernatants against strains F2, F3 and F8 surpassing 73%. This study confirmed that Fusarium is the dominant pathogenic fungal group causing root rot of P. cyrtonema Hua. Furthermore, highly effective antagonistic endophytes were preliminarily identified, offering candidate strains and a theoretical foundation for the green management of root rot in P. cyrtonema Hua. Full article

Fusarium oxysporum f. sp. lycopersici threatens tomato production globally, resulting in severe yield losses. Nanotechnology and organic amendments are emerging as sustainable disease management practices to combat the drawbacks of chemical fungicides. This study evaluated the efficacy of nano Zn-Cu micronutrient solution and canola biofumigant on disease incidence, severity, and disease progression under field and greenhouse conditions. Tomato plants showing wilt symptoms were collected from two distinct agroecological locations of the Limpopo Province, South Africa. Morphological and molecular identification confirmed the presence of the virulent isolate. Under greenhouse conditions, weekly application of nano Zn-Cu significantly reduced wilt severity on two tomato cultivars, with 43–86% disease suppression, while canola biofumigant recorded disease suppression of 66–86%. The field experiment showed fewer disease incidences (0–40%) and severity (4–35%) on tomato plants sprayed weekly with nano Zn-Cu. This treatment maintained lower values of Area Under Disease Progress Curve (AUDPC), suggesting slower disease development. Similarly, canola biofumigant reduced disease development relative to the untreated control. Under both greenhouse and field experiments, untreated plants were severely infected, recording approximately 70% disease severity. This study demonstrated the potential of nano Zn-Cu micronutrients and canola biofumigant as sustainable solutions for managing Fusarium wilt of tomato, thereby contributing to integrated disease management. Full article

Strawberries, as an important economic crop, are widely planted worldwide. Fusarium oxysporum, belonging to FOSC (Fusarium oxysporum species complex), is widely present in plants. Among them, Fusarium oxysporum f. sp. fragariae (Fof) is one of the most important pathogens on strawberry and has pathogenic specificity toward strawberry hosts. In recent years, diseases caused by Fof have seriously threatened the strawberry industry. Secreted in Xylem (SIX) genes play important and different roles in F. oxysporum. In this study, we knocked out SIX9 in Fof to analyze its functions. The mycelial growth rate of ΔFofSIX9 was significantly lower than that of the wild type, but the difference in spore production was not significant. The pathogenicity of ΔFofSIX9 toward four different representative strawberry varieties was significantly reduced, manifested by the decrease in the severity of plant wilt, root rot, and crown rot. In addition, compared to the wild type, the activities of superoxide dismutase (SOD) and catalase (CAT) in ΔFofSIX9-infected plants were significantly increased, while the content of malondialdehyde (MDA), hydrogen peroxide (H₂O₂), and superoxide anion (O₂⁻) were significantly decreased. So ∆FofSIX9 could reduce the pathogenicity of the wild type by affecting the host plant’s defense response against infection of Fof. Full article

Fusarium oxysporum-associated disease symptoms in rice (Oryza sativa L.) seedlings represent an experimentally tractable model for evaluating microbiome-mediated disease suppression under controlled conditions. Biological control of Fusarium-associated disease development in rice provides a promising ecological alternative to chemical fungicides. However, the mechanisms underlying the spatial reconfiguration of the host plant multicompartment microbiome in response to complex inoculants remain insufficiently understood. In this study, we investigated the ability of the monoculture Bacillus amyloliquefaciens Bn1 (B. amyloliquefaciens Bn) and phototrophic–heterotrophic consortia composed of Nostoc sp. J-1 and B. amyloliquefaciens Bn1 to suppress Fusarium oxysporum infection, with parallel profiling of bacterial and fungal communities in rhizosphere soil, the root endosphere, and the phyllosphere using 16S rRNA and ITS amplicon sequencing. Phenotypic screening showed that microbial inoculant application significantly reduced the disease index by up to 55% while maintaining plant dry weight. The protective phenotype was not primarily associated with shifts in alpha diversity, but rather with compartment-specific reorganization of microbial communities. These findings suggest that biological control efficacy was associated less with the overall taxonomic scale of microbiome disturbance than with the formation of a functionally balanced, compartment-specific holobiont architecture but by the formation of a functionally balanced, compartment-specific holobiont architecture, providing a conceptual basis for the targeted design of next-generation phototrophic–heterotrophic biopreparations. Full article

Moringa oleifera seed cake is the byproduct of moringa oil extraction and the most valuable source of 4-(α-L-rhamnosyloxy)benzyl glucosinolate (glucomoringin; GMG), the precursor of 4-(α-L-rhamnosyloxy)benzyl isothiocyanate (moringin; GMG+M). The vascular fungus Fusarium oxysporum f. sp. lycopersici (FOL) is an important soil-borne pathogen of tomato in cultivated areas worldwide. Coating seeds with phytochemicals has been reported to prevent seed transmission and control seedling infection. In this work, GMG was extracted and purified from moringa seed cake on the multigram scale, and GMG+M solutions obtained through controlled hydrolysis of the precursor with commercial myrosinase were evaluated against the pathogen both in vitro and in planta. FOL conidia germination and mycelial growth were significantly inhibited by GMG+M solutions in the range 1–1000 µM, in a dose-dependent manner, compared to GMG and control treatments, which did not differ significantly. Interestingly, the coating of tomato var. crovarese seeds with GMG or GMG+M (100 µM) resulted in equally effective reduction (70%) of the disease severity in post-emergence, suggesting a plant-mediated mechanism underlying the efficacy of the intact glucosinolate. Seed coating with both phytochemicals triggered polyphenol oxidase (PPO) activity in five-day-old tomato sprouted rootlets. This study highlighted the potential biotechnological value of M. oleifera seedcake for the development of a sustainable biopesticide. Full article

Interest in the rearing of Hermetia illucens L. by-products has increased in recent years. This study evaluated the effects of H. illucens frass, obtained from larvae reared on a Gainesville diet, for the control of Fusarium oxysporum f. sp. lycopersici (Sacc.) W.C. Snyder & H.N. Hansen (FOL). Greenhouse trials were conducted comparing thermally treated (70 °C for 60 min) and untreated frass applied at different concentrations (1–20% v/v). Disease severity, disease incidence, area under the disease progress curve (AUDPC), and plant fresh weight were assessed. Frass application significantly reduced disease severity and incidence, compared with the inoculated untreated control, with the greatest reductions observed in the 20% thermally untreated treatment and in the 5% and 10% thermally treated treatments under the greenhouse conditions of this study. The area under the disease progress curve (AUDPC) analysis suggested a reduction in disease progression over time. No significant differences were observed between thermally treated and untreated frass. Fresh weight was mainly influenced by frass dose, and the highest values were obtained with treatments at 10% and 20%. H. illucens frass showed preliminary potential as a sustainable starter for the suppression of Fusarium wilt of tomato under greenhouse conditions. Full article