Fungus Fusarium Research Articles

Analysis of Wheat Grain Infection by Fusarium Mycotoxin-Producing Fungi Using an Electronic Nose, GC-MS, and qPCR.

Fusarium graminearum and F. culmorum are considered some of the most dangerous pathogens of plant diseases. They are also considerably dangerous to humans as they contaminate stored grain, causing a reduction in yield and deterioration in grain quality by producing mycotoxins. Detecting Fusarium fungi is possible using various diagnostic methods. In the manuscript, qPCR tests were used to determine the level of wheat grain spoilage by estimating the amount of DNA present. High-performance liquid chromatography was performed to determine the concentration of DON and ZEA mycotoxins produced by the fungi. GC-MS analysis was used to identify volatile organic components produced by two studied species of Fusarium. A custom-made, low-cost, electronic nose was used for measurements of three categories of samples, and Random Forests machine learning models were trained for classification between healthy and infected samples. A detection performance with recall in the range of 88-94%, precision in the range of 90-96%, and accuracy in the range of 85-93% was achieved for various models. Two methods of data collection during electronic nose measurements were tested and compared: sensor response to immersion in the odor and response to sensor temperature modulation. An improvement in the detection performance was achieved when the temperature modulation profile with short rectangular steps of heater voltage change was applied.

Food Safety Aspects of Breeding Maize to Multi-Resistance against the Major (Fusarium graminearum, F. verticillioides, Aspergillus flavus) and Minor Toxigenic Fungi (Fusarium spp.) as Well as to Toxin Accumulation, Trends, and Solutions-A Review.

Maize is the crop which is most commonly exposed to toxigenic fungi that produce many toxins that are harmful to humans and animals alike. Preharvest grain yield loss, preharvest toxin contamination (at harvest), and storage loss are estimated to be between 220 and 265 million metric tons. In the past ten years, the preharvest mycotoxin damage was stable or increased mainly in aflatoxin and fumonisins. The presence of multiple toxins is characteristic. The few breeding programs concentrate on one of the three main toxigenic fungi. About 90% of the experiments except AFB1 rarely test toxin contamination. As disease resistance and resistance to toxin contamination often differ in regard to F. graminearum, F. verticillioides, and A. flavus and their toxins, it is not possible to make a food safety evaluation according to symptom severity alone. The inheritance of the resistance is polygenic, often mixed with epistatic and additive effects, but only a minor part of their phenotypic variation can be explained. All tests are made by a single inoculum (pure isolate or mixture). Genotype ranking differs between isolates and according to aggressiveness level; therefore, the reliability of such resistance data is often problematic. Silk channel inoculation often causes lower ear rot severity than we find in kernel resistance tests. These explain the slow progress and raise skepticism towards resistance breeding. On the other hand, during genetic research, several effective putative resistance genes were identified, and some overlapped with known QTLs. QTLs were identified as securing specific or general resistance to different toxicogenic species. Hybrids were identified with good disease and toxin resistance to the three toxigenic species. Resistance and toxin differences were often tenfold or higher, allowing for the introduction of the resistance and resistance to toxin accumulation tests in the variety testing and the evaluation of the food safety risks of the hybrids within 2-3 years. Beyond this, resistance breeding programs and genetic investigations (QTL-analyses, GWAM tests, etc.) can be improved. All other research may use it with success, where artificial inoculation is necessary. The multi-toxin data reveal more toxins than we can treat now. Their control is not solved. As limits for nonregulated toxins can be introduced, or the existing regulations can be made to be stricter, the research should start. We should mention that a higher resistance to F. verticillioides and A. flavus can be very useful to balance the detrimental effect of hotter and dryer seasons on aflatoxin and fumonisin contamination. This is a new aspect to secure food and feed safety under otherwise damaging climatic conditions. The more resistant hybrids are to the three main agents, the more likely we are to reduce the toxin losses mentioned by about 50% or higher.

Zearalenone triggers programmed cell death and impairs milk fat synthesis via the AKT-mTOR-PPARγ-ACSL4 pathway in bovine mammary epithelial cells.

Zearalenone (ZEN), a mycotoxin from Fusarium fungi, impairs fertility and milk production in female animals; however, the mechanisms remain poorly understood. Using the bovine mammary epithelial cells (MAC-T) as the model, this study investigated the impacts of ZEN on programmed cell death (PCD) and milk fat synthesis and explored the underlying mechanism. We found that 10ng/mL prolactin (PRL) notably enhanced the differentiation of MAC-T cells, promoting the expression of genes related to the synthesis of milk fat, protein, and lactose. Next, the toxic effects of different doses of ZEN on the differentiated MAC-T with PRL treatment were determined. 10 and 20 μM ZEN significantly reduced cell viability, induced oxidative stress, and triggered PCD (e.g., apoptosis and necrosis). Notably, ZEN exposure downregulated the mRNA/protein levels of critical factors involved in milk fat synthesis by disrupting the AKT-mTOR-PPARγ-ACSL4 pathway. Interestingly, melatonin (MT), known for its antioxidant properties, protected against the above ZEN-induced effects by enhancing the binding of PPARγ to the promoter regions of ACSL4, which led to the upregulated expression of the ACSL4 gene. These results underscored the potential of MT to mitigate the adverse effects of ZEN on mammary cells, highlighting a way for potential therapeutic intervention.

Antifungal efficacy and phytochemical characterization of citronella (Cymbopogon winterianus Jowitt ex Bor) essential oil against fungal pathogens causing severe diseases in Mentha arvensis L.

Mentha arvensis L. (family Lamiaceae) is one of the important medicinal plants and India is the largest producer of Mentha oil in the world, contributing about 80% of the total global production followed by China (9%), Brazil (7%) and the USA (4%). However, this crop suffers quantitative and qualitative losses due to the wilt and leaf spot diseases caused by the fungi Fusarium oxysporum and Alternaria alternata, respectively; therefore, an attempt has been made for the management of these fungal pathogens. The citronella essential oil was extracted by hydro-distillation method (Clevenger, 1928). The oil thus extracted was used for in vitro antifungal efficacy against the both fungi F. oxysporum and A. alternata, using poison food technique. The results showed that the minimum inhibitory concentration (MIC) of the citronella oil against F. oxysporum and A. alternata was 1.0 μL/mL; however, it was cidal in nature at 1.2 μL /mL and 1.5 μL/mL against both fungi, respectively. Further, phytochemical characterization of citronella oil was done using GC/GC-MS. Gas chromatographic analysis of the citronella oil revealed 18 phytoconstituents which were identified by retention indices aided with NIST-MS database. The major constituents of essential oil were citronellal (28.78%), geraniol (26.31%), citronellol (12.90%), geranial (9.85%), and neral (7.9%). The findings of the current study show that citronella oil could be an alternative to synthetic fungicides, after detailed investigations.

Оптимизация молекулярно-генетической диагностики возбудителей фузариозов на озимой тритикале (×Triticosecale Wittm . & A. Camus)

Phytopathogenic fungi are among the most common and dangerous plant pathogens, causing significant crop losses and considerable economic costs. The greatest damage to agricultural crops is caused by fungi of the genus Fusarium, making the study of their distribution, species diversity and diagnostic methods more in demand every year. This is particularly important for breeding purposes. The determination of the species composition of this pathogen allows not only to evaluate the level of infestation, but also to perform preventive selection for resistance to Fusarium. The aim of the study was to test the developed primers and probes for the identification of the most common representatives of the genus Fusarium such as F. culmorum, F. graminearum and F. poae. Pure cultures of fungi obtained from different collections of microorganisms were used as research material. We studied 35 varieties of winter triticale from the RSAU-MTAA collection. In order to differentiate the studied species, oligonucleotides were designed for a fragment of the Galactose oxidase (GalOx) gene and its homologous genes from the NCBI database. Diagnosis was performed by real-time polymerase chain reaction (qPCR). The main analytical characteristics of the developed primers such as specificity and sensitivity were determined. Screening of 35 varieties of winter triticale showed their infestation with fungi of the genus Fusarium. It was revealed that the predominant species was F. poae, which was found in 95.2% of the varieties. For F. graminearum, the highest prevalence was found between 2020 and 2021, when the infestation of triticale samples was 31.4% and 91.4%, respectively. F. culmorum had the lowest percentage of infestation, being found in only 20% of all samples. In addition, the winter triticale varieties of the 2022 harvest K‑1–19#14 K‑3851 PRAG502 (Dagestan) and K‑1–19#42 K3727 SNT‑5/92 (Omsk region) were identified as the least susceptible to infestation by the studied species of fungi.

Displacement of toxigenic Fusarium species by atoxigenic Aspergillus flavus (Aflasafe KE01) application in maize fields in lower Eastern Kenya

Maize is grown in areas with environmental conditions that are ideal for growth of most cereal pathogens such as Fusarium fungi. However, there is lack of effective fungicides to control fumonisin producing Fusarium. This study was conducted to determine the efficacy of atoxigenic Aspergillus flavus (Aflasafe KE01) on the population of Fusarium species in maize fields. The study was carried out in four sub counties in lower Eastern Kenya (Kaiti, Kathiani, Nzambani and Wote). Twenty-four maize fields were selected in each sub county where 12 fields were treated with Aflasafe KE01, while 12 fields comprised the untreated controls. Aflasafe KE01 was applied by hand broadcasting in the maize fields two to three weeks before tasselling of maize. Maize grain samples were collected from each field at harvest and ground using a Bunn coffee mill grinder. Fusarium species were isolated from the ground maize using pour plate method following serial dilution on low strength potato dextrose agar (PDA)and Spezieller Nahrstoffarmer. The results showed that application of Aflasafe KE01 effectively displaced toxigenic Fusarium species in maize fields. Maize samples from Aflasafe KE01 treated maize fields recorded significantly lower incidence (41%) of the Fusarium species compared to untreated maize fields (60%) (p≤0.01). These results indicate that Aflasafe KE01 is a potential biopesticide for the biocontrol of Fusarium species in maize. Key words: Aflasafe KE01, atoxigenic Aspergillus sp, Fusarium species, maize.

Main pests and diseases of soybean of the northern ecotype in the conditions of the non-chernozem zone

For the first time in the Central Region of the Non-Chernozem zone, the main pathogens affecting soybean varieties of the northern ecotype in this region - downy mildew, fusariosis, and growth retardation virus were studied; the degree of their pathogenicity was established. The species composition of potential soybean pests has been established. The economic threshold of nodule weevil injuriousness has been determined. Studies conducted in soybean crops of the northern ecotype in the conditions of the Kaluga region have established a complex of pests and diseases. The main insect pests of soybeans of the northern ecotype are represented by the orders Coleoptera, Lepidoptera, Heteroptera, Thysanoptera. The arachnid class is represented by the red spider. The main pathogens affecting soybean varieties of the northern ecotype are fungi of the genus Fusarium sp., Perono-spora, Ascochyta; viruses – growth retardation virus, Southern Mosaic bean virus, Southern Mosaic Virus, Strawberry wither tip virus.

Bacterial agents as the basis of biofungicides effective against toxin-producing fungi of the genus Fusarium (review)

Bacterial agents as the basis of biofungicides effective against toxin-producing fungi of the genus Fusarium (review)

ГРИБЫ РОДА FUSARIUM – МНОГООБРАЗИЕ СВОЙСТВ, ЗНАЧЕНИЕ КАК ОБЪЕКТОВ ПРОМЫШЛЕННОЙ БИОТЕХНОЛОГИИ

The paper presents an analytical review of the variety of properties of fungi of the genus Fusarium. An analysis of available experimental studies has shown that this genus has many amazing properties. This is expressed in the production of metabolites that are both extremely harmful to humans, animals and plants, possessing all the characteristics of highly pathogenic substances, exceeding the activity of poisons, and very useful, with medicinal properties. These metabolites find their place both in the treatment of a wide range of diseases and in the form of dietary supplements for humans and animals, as well as stimulants for plant growth and development.

Inactivation of isolated fungi on Erythrina velutina Willd. seeds through atmospheric plasma.

This study aimed to evaluate the effect of atmospheric plasma application on the inactivation of fungi on the surface of Erythrina velutina seeds and on isolated fungal colonies. Two experiments were conducted using a completely randomized design. First, plasma was applied to the surface of the seeds using helium gas and atmospheric plasma for 3, 6, and 9 min in addition to the control (untreated seeds), constituting seven treatments with five repetitions each. In the second experiment, Petri dishes containing the inoculum of different fungi were treated with atmospheric air plasma for 3, 6, and 9 min (Air-3, Air-6, and Air-9) and were compared with untreated fungi in Petri dishes without treatment (control), totaling four treatments and five repetitions each. We found that the application of atmospheric air plasma to E. velutina seeds for 9 min had an antimicrobial effect on the fungi Aspergillus niger, Aspergillus flavus, Fusarium sp., Brachysporium sp., and Rhizopus sp. The formation of fungal colonies isolated from E. velutina seeds was also inhibited by 3 min of exposure to atmospheric air plasma, except for A. niger, whose inhibition occurred after 6 min of exposure to atmospheric plasma.

Identification of Ochrobactrum as a bacteria with transstadial transmission and potential for application in paratransgenic control of leishmaniasis.

Leishmaniasis is a zoonotic vector-borne disease with worldwide distribution. All current approaches in leishmaniasis control or development of vaccines/cures showed only limited success. Recently, paratransgenesis has been marked as a promising strategy for leishmaniasis control. Thus, the investigations of the gut microbial content of sand flies have gained popularity. Gut microbial composition of the laboratory colony of Phlebotomus papatasi was investigated via microbial culturomics approach which refers to the combination of multiple culture conditions and different selective and/or enriched culture mediums, followed by 16S rDNA sequencing. Investigations were conducted on three offspring generations, with six samplings of immature stages (four larval samplings, one pre-pupa, one pupa) and samplings of adults before and after blood feeding. The aim was to determine if microbiome changes during the sand fly development and to identify bacteria with transstadial potential. The presence of 8 bacterial taxa (Bacillus sp., Terribacillus sp., Staphylococcus sp., Alcaligenes sp., Microbacterium sp., Leucobacter sp., Ochrobactrum sp. and Enterobacter sp.), 2 fungi (Fusarium sp. and Acremonium sp.) and 1 yeast (Candida sp.) were recorded. Gram-positive bacteria were more diverse, but gram-negative bacteria were more abundant. All taxa were recorded among immature stage samples, while only one bacterium was detected in adults. Microbial diversity among larval samples was stable, with a steady decrease in pre-pupa and pupa, resulting in the survival of only Ochrobactrum sp. in adults. Abundance of microbes was higher when larvae were actively feeding, with a gradual decrease after larvae stopped feeding and commenced pupation. Ochrobactrum sp. is the bacteria with transstadial potential, worthy of future in-depth analysis for the application in paratransgenic approach for the control of Leishmania sp.

Quantitative composition and taxonomic structure of endophytes of agricultural crops

Various vegetative organs of the studied crops yielded 320 isolates of cultivated forms of micromycetes, with a predominance of filamentous fungi (249 strains). The level of colonization by fungi varied widely, ranging from 6 to 40%. This indicator was lower for yeast, ranging from 2 to 12%. The isolation ratio of fungal strains ranged from 0.08 to 0.54, while yeast strains ranged from 0.02 to 0.2. The taxonomic composition of endophytic micromycetes complexes in the studied agrocultures included 7 genera of filamentous fungi (Penicillium, Aspergillus, Fusarium, Trichoderma, Beauveria, Metarhizium, and Cladosporium) and 4 genera of yeasts and yeast-like fungi (Rhodotorula, Aureobasidium, Metschnikowia, and Cryptococcus). The greatest taxonomic diversity was observed in soybean and sweet clover. Barley and sainfoin also exhibited considerable diversity. The quantitative composition and taxonomic structure of endophytes are largely influenced by species, physiological state and stage of development of the host plant, type of plant tissues and organs, and environmental conditions.

Antifungal effectiveness of some essential oils and their mixtures against Fusarium oxysporum f.sp cubense that causes fusarium wilt disease of banana plants

Antifungal effectiveness of several essential oil botanical pesticides and their mixtures against the fungus Fusarium oxysporum f.sp. cubense (Foc) which causes fusarium wilt disease of banana plants in vitro, was conducted from March to July 2023. The aim of the study was to obtain an effective botanical pesticide formulation and the right concentration for controlling the Foc causing Fusarium wilt disease in banana plants. The study was arranged in a completely randomized design in factorials with three replications. The experiment was carried out using two methods: a) Suppressing colony diameter using Potato Dextrose Agar (PDA) medium, b). Suppressing colony biomass using Potato Dextrose Broth (PDB) medium. The treatment was the formulation of essential oil (F) botanical pesticides as the first factor; F1 (Cymbopogon flexuosus oils), F2 (C. nardus essential oils), F3 (Eugenia aromatica leaf essential oils), F4 (Cinnamomum burmanii leaf oils), F5 (F1+F2), F6 (F1+F3), F7 (F1+F4) and F8 (F2 +F3), F9 (F2+F4) and F10 (F3+F4) The level of concentration (C) as a second factor C1(1000 ppm) and C2(2000 ppm). The results showed that the F3 (E. aromatica leaf oils) treatment had the best antifungal activity against Foc. At a concentration of 2000 ppm inhibition of the diameter growth and colony biomass reached 100%, followed by the F1 treatment (C. flexuosus oils) up to 89.73% and 95.75%, the F2 treatment (C. nardus oils) reach 84.58% and 89.67% and the lowest antifungal activity is F4 (C. burmanii leaf oils) which only 77.08% and 84.50%. The best mixed formulations were F5(F1+ F3) and F8(F2 + F3), at the same concentration suppression of colony growth reaching 100%. In general, mixed essential oils formulation have shown to increase the effectiveness of the antifungal activities.

Bioassay-guided isolation of constituents from the endophytic fungi Fusarium solani inhabiting Rhizophora apiculata Blume

Bioassay-guided isolation of constituents from the endophytic fungi Fusarium solani inhabiting Rhizophora apiculata Blume

Controlling Tomato Fusarium Wilt Disease through Bacillus thuringiensis-Mediated Defense Primining.

Fusarium wilt caused by the fungus Fusarium oxysporum f. sp. lycopersici (Fol) (Sacc.) W.C. Snyder and H.N. Hans is one of the most prevalent and devastating diseases of tomato plants (Solanum lycoprsicum L.) that leads to a severe reduction in crop yield almost worldwide. Evaluation of biocontrol potential of Bacillus thuringiensis (Bt) isolate IBRC-M11096, against Fol in tomato through primin. qRT-PCR technique was applied to analyze the effect of the strain on the hormonal defensive pathways; transcriptional responses of jasmonic acid (COI1, Pin2) and salicylic acid (NRP1 and PR1) pathway genes in Bt-treated plants following inoculation of Fol as compared to the plants only challenged with Fol. Also, the potential of the bacterial strain as a biocontrol agent was studied by evaluating growth indices and area under disease progress curve (AUDPC). The transcription of both defensive hormonal pathway genes (COI1, Pin2, NPR1, PR1) increased due to bacterial priming. The bacterial priming reduced the AUDPC compared to the inoculation with only Fol. The strain reduced the disease symptoms, and compared to the plants only challenged with the fungus, the bacterial strain significantly raised shoot dry and fresh weights and root dry weight. Priming with the Bt strain led to improved shoot and root growth indices, reduced AUDPC, and fortified responses of both JA and SA hormonal pathways. However, further full-span studies are required to judge the efficacy of the bacterial strain in the biological control of tomato fusarium wilt under field conditions.

Allelopathic effects of phenolic acid extracts on Morchella mushrooms, pathogenic fungus, and soil-dominant fungus uncover the mechanism of morel continuous cropping obstacle.

The prominent problem of continuous cropping obstacle has been frustrating the morel farming. To deepen the understanding on morel continuous cropping obstacle, the allelopathic effects of phenolic acid extracts from morel continuous cropping soils on growth and development of Morchella sextelata, M. eximia, M. importuna, pathogenic fungus Fusarium sp. and soil-dominant fungus Chaetomium sp. were investigated. These effects were expressed as response index (RI). Under actual content of phenolic acids (6.150μg/g fresh mixed continuous cropping soil), the mycelial growth of all tested morel strains was inhibited (RI < 0), while the allelopathic effect of control phenolic acids (4.252μg/g fresh mixed control soil) was between promotion and inhibition, which suggested that the phenolic acid extracts from morel continuous cropping soils may exhibit certain extent of autotoxicity for the existence of morel-specific allelochemicals. In addition, the aggravated pigmentation and reduced occurrence of sclerotium in three Morchella fungi at growth inhibitory concentrations of phenolic acids indicated the induction of morel strain aging. Meanwhile, most concentrations of phenolic acids showed stimulatory effects on sporulation of Fusarium sp. and Chaetomium sp. (RI > 0), manifesting the enrichment of soil-borne pathogenic fungi and dominance of certain fungal population in soil ecosystem. Collectively, the allelopathic effects of phenolic acid extracts play an instrumental role in morel continuous cropping obstacle. The study will be beneficial for healthy development of morel artificial cultivation.

Solid-state fermentation of pigment producing endophytic fungus Fusarium solani from Madiwala lake and its toxicity studies

Solid-state fermentation of pigment producing endophytic fungus Fusarium solani from Madiwala lake and its toxicity studies

Biogenic silver nanoparticles' antibacterial activity and cytotoxicity on human hepatocarcinoma cells (Huh-7).

Exploring diverse synthetic pathways for nanomaterial synthesis has emerged as a promising direction. For example, silver nanoparticles (AgNPs) are synthesized using different approaches yielding nanomaterials with distinct morphological, physical and biological properties. Hence, the present study reports the biogenic synthesis of silver nanoparticles using the aqueous secretome of the fungus Fusarium oxysporum f. sp. cubense (AgNP@Fo) and orange peel extract (AgNP@OR). The physical and morphological properties of synthesized nanoparticles were similar, with AgNP@Fo measuring 56.43 ± 19.18 nm and AgNP@OR measuring 39.97 ± 19.72 nm in size. The zeta potentials for the nanoparticles were low, -26.8 ± 7.55 and -26.2 ± 2.87 mV for AgNP@Fo and AgNP@OR, respectively, demonstrating a similar negative charge. The spherical morphologies of both nanoparticles were evidenced by Scanning Transmission Electron Microscopy (STEM) and Atomic Force Microscopy (AFM). However, despite their similar physical and morphological properties, AgNPs demonstrated different bioactivities. We evaluated and compared the antimicrobial efficacy of these nanoparticles against a range of bacteria, such as Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Escherichia coli. The AgNP@Fo showed Minimum Inhibitory Concentration (MIC) values ranging from 0.84 to 1.68 μg mL-1 and were around ten times more potent compared to AgNP@OR. The anticancer activities of both nanoparticles were investigated using human hepatocarcinoma cells (Huh-7), where AgNP@Fo exhibited around 20 times higher cytotoxicity than AgNP@OR with an IC50 value of 0.545 μmol L-1. Anticancer effects were demonstrated by the MTT, confirmed by the calcein-AM assay and fluorescence imaging. This study establishes solid groundwork for future exploration of molecular interactions of nanoparticles synthesized through distinct biosynthetic routes, particularly within bacterial and cancerous cell environments.

Perfil de metabólitos secundários produzidos por Pseudomonas sp. isolado PY-122 e PY-142 como agente de biocontrole contra a doença de fusarium wilt em pimentas

Abstract Fusarium wilt is an important disease on chili plants caused by the fungus Fusarium oxysporum. This study aims to determine the effectiveness of secondary metabolites from 2 Pseudomonad isolates in controlling Fusarium wilt in chili plants and their effect on chili plant growth. This research was conducted in two stages, namely in vitro, which was carried out in the plant health laboratory and greenhouse, Faculty of Agriculture, Universitas Pembangunan Nasional Veteran Jawa Timur, and in vivo which was carried out in chili plantations known to be endemic to Fusarium wilt in Menganti, Gresik. The research design used in this study was Completely Randomized Design for in vitro testing and Randomized Group Design for in vivo testing by testing 9 treatments repeated 3 times. The treatment tested was control, secondary metabolite application of Pseudomonas isolates PY-122 and PY-142 with concentrations of 20% 30%, 40% and 50%. The variables observed were inhibition of secondary metabolites on the growth of Fusarium fungus, disease incubation period, disease severity index, and plant growth. Sequencing results with 16rRNA gene markers for both Pseudomonas isolates showed similarities to Pseudomonas sp. The results showed that the treatment of secondary metabolite PY-142 with a concentration of 50% showed the highest consistent inhibition. In the greenhouse and field tests, the two isolates slowed down the disease incubation period and development compared to controls. In agronomical observations, the average plant height, number of leaves, root length, and appearance of the first flower on the treated plants were higher and more numerous than the control plants.

Nanoscale sulfur alters the bacterial and eukaryotic communities of the tomato rhizosphere and their interactions with a fungal pathogen

Nanoformulations of sulfur have demonstrated the potential to enhance plant growth and reduce disease incidence when plants are confronted with pathogens. However, the impact of nanoscale sulfur on microbial communities in close contact with the plant root, known as the rhizosphere, remain poorly characterized. In this study, we investigate the impact of three formulations of sulfur; bulk sulfur, uncoated (pristine) sulfur nanoparticles, and stearic acid coated sulfur nanoparticles, on the rhizosphere of tomato plants. Tomato plants were additionally challenged by the pathogenic fungus Fusarium oxysporum f. sp. Lycopersici. Employing bacterial 16S rRNA gene sequencing, along with recently in-house designed peptide nucleic acid clamps to facilitate the recovery of microeukaryote sequences, we performed a comprehensive survey of rhizosphere microbial populations. We found the largest influence on the composition of the rhizosphere microbiome was the presence of the fungal pathogen. However, sulfur amendments also drove state changes in the rhizosphere populations; for example, enriching the relative abundance of the plant-beneficial sulfur-oxidizing bacterium Thiobacillus. Notably, when investigating the response of the rhizosphere community to the different sulfur amendments, there was a strong interaction between the fungal pathogen and sulfur treatments. This resulted in different bacterial and eukaryotic taxa being enriched in association with the different forms of sulfur, which was dependent on the presence of the pathogen. These data point to nano formulations of sulfur exerting unique shifts in the rhizosphere community compared to bulk sulfur, particularly in association with a plant pathogen, and have implications for the sustainable use of nanoscale strategies in sustainable agriculture.