Fusarium Species Research Articles

Survival Dynamics of Invasive Fungal Diseases in Pediatric Hemato-Oncology Patients at a Tertiary Medical Facility in Mexico from July 2020 to July 2023

Abstract Background Invasive fungal diseases (IFD) have been increasing in prevalence over the past two decades, with filamentous fungi being the most common cause. However, candidiasis remains the predominant etiology of infection, especially in cases of neutropenic fever accompanied by neutropenic colitis. The prevalence of infections caused by Aspergillus species, Mucor species, Fusarium, and other species is higher among individuals with severe and extended neutropenia and those who have undergone hematopoietic progenitor cell transplantation. Methods A retrospective, descriptive, observational study was conducted to identify cases of patients diagnosed with invasive fungal diseases, categorizing them as possible, probable, or confirmed. In our comprehensive analysis of cases, we prioritize the examination of diseases induced by filamentous fungi, while considering the specific chemotherapy regimen administered and the particular oncological condition. Results The predominant etiology observed was invasive aspergillosis, followed by mucormycosis. A total of 18 cases suggestive of invasive Aspergillosis were identified, but clinical or histopathological investigations were not conducted due to limitations. The majority of cases were pulmonary, accounting for 92% of cases, while rhinosinusal involvement was identified in 8%. Factors such as clinical characteristics, imaging studies, serum galactomannan determination, and microbiological culture were considered. The patient survival rate was found to be 86.7%, with an average treatment duration of six weeks. A mortality rate of 3.7% was observed due to the underlying disease during the consolidation phase of invasive fungal diseases. Conclusion In our study, invasive aspergillosis emerged as the predominant invasive fungal disease in pediatric hemato-oncology patients. Despite challenges in conducting comprehensive investigations, our findings underscore the importance of timely diagnosis and management. The 86.7% survival rate reflects the efficacy of the treatment approach employed, while the observed mortality emphasizes the impact of underlying diseases on outcomes. This study contributes valuable insights to the understanding and improvement of survival dynamics in pediatric patients facing invasive fungal diseases.

Response of Alternaria and Fusarium Species to Low Precipitation in a Drought-Tolerant Plant in Morocco

The plant mycobiome plays a crucial role in the host life cycle, influencing both healthy and diseased states, and is essential for plant tolerance to drought. In this study, we used ITS metabarcoding to investigate the fungal community of the drought-resistant plant Malva sylvestris L. in Morocco along a gradient of precipitation, encompassing subhumid and semi-arid environments. We sampled three biotopes: rhizosphere, bulk soil, and root endosphere. Our findings revealed an absence of beta-diversity differences between bulk soil and rhizosphere, indicating that the plant does not selectively influence its rhizosphere mycobiome. Additionally, ASVs belonging to the genus Alternaria represented up to 30% of reads in the plant’s roots and correlated with drought (p = 0.006), indicating a potential role for this fungal genus in mitigating drought, possibly as part of the dark septate endophyte group. Root staining and microscopic observation revealed extensive colonization by fungal hyphae and microsclerotia-like structures. Furthermore, ASVs identified as Fusarium equiseti were also correlated with low precipitation and recognized as a hub taxon in the roots. However, it remains uncertain whether this species is pathogenic or beneficial to the plant. These insights contribute to our understanding of the plant mycobiome’s role in drought tolerance and highlight the importance of specific fungal taxa in supporting plant health under varying environmental conditions. Future research should focus on characterizing these taxa’s functional roles and their interactions with the host plant to further elucidate their contributions to drought resistance.

Biodiversity of Aspergillus Species and Their Mycotoxin Production Potential in Dry Meat.

This study aimed to examine fungi diversity in dried beef meat sold in Ekiti State, characterize the isolated fungi, and determine the aflatoxin-producing ability of the Aspergillus fungi in the samples. Dried beef meat was collected from different markets in Ekiti State and screened for the presence of filamentous fungi using molecular methods. Samples were cultured aseptically on potato dextrose agar (PDA) for fungi isolation, and molecular identification was performed using DNA extraction, Polymerase chain Reaction (PCR), ITS-1/ITS-4 primer pair, and nucleotide sequencing. The results obtained indicated a range of filamentous fungi genera including Aspergillus, Rhizopus, Penicillium, Fusarium, Cladosporium, Alternaria, and other fungi species contaminating the dried meat at (43%), (42%), (3%), (2%), (2%), (1%), and (7%), respectively. High incidences were recorded for Aspergillus flavus, Aspergillus niger, and Aspergillus fumigatus in most of the screened samples. Aspergillus flavus accounted for (24.7%) of all the Aspergillus species isolated with the presence of the gene needed for aflatoxin production. The occurrences of these filamentous fungal species pose a cause for concern, as most of these fungal species are known producers of certain toxic substances. Maximum likelihood phylogenetic analysis showed a high similarity index score, which indicated a good relationship between isolated Aspergillus Species and the closely related strains from GenBank, isolated from different sources and countries. The implication of this study is that consumer health may be at risk through exposure to contaminated dried meat.

A Study of Clinico-Microbiological Profile and Treatment Outcomes of Infectious Keratitis.

Background Infectious keratitis (IK) is one of the major causes of corneal blindness in developing and developed nations.Numerous infections, including bacterial, fungal, viral, and protozoa, have been linked to IK. Corneal perforations can happen as one of the complications of IK. In this study, we aim to determine the clinical and microbiological profile and to studythe treatment outcomes of IK. Material and methods It is a prospective, observational, and experimental study conducted in a tertiary care hospital and research centerin Western Maharashtra, India, from September 2022 to June 2024. The sample size was 107 patients with IK. All patients were above 15 years of age, and all cases of microbial keratitis were within the inclusion criteria. Patients less than 15 years of age, patients with any other associated corneal pathology, healed cases of infectious keratitis, peripheral ulcerative keratitis, patients not willing to participate in the study, or not giving consent were excluded. Patients were examined thoroughly, and corneal scraping samples were collected and sent for microbiological examination. Appropriate treatment was provided through medical or surgical management, and treatment outcomes were evaluated during frequent follow-up visits. Results In our study, the majority of patients originated from rural areas, with most being over 60 years of age. Diabetes mellitus was seen in 24.3%, and a history of ocular trauma was present in 48.5% of patients. Staphylococcus epidermidis (3.74%) was the most common organism seen on gram staining, followed by Staphylococcus aureus (2.8%). Pseudomonas aeruginosa was the only gram-negative organism seen. The number of patients who had fungal isolates positive on culture was 57%, 12.1% had bacterial, and 30% had no growth of microorganisms. Fusarium species were seen in 39.2% of culture isolates, followed by Aspergillus flavus and Niger in 7.47% each. In 96% of medically managed patients, ulcers healed within two months. All ulcers with severe and moderate depth required therapeutic penetrating keratoplasty. A graft was in place in 95.2% after therapeutic penetrating keratoplasty, while one patient had graft rejection, and in one patient, endophthalmitis was seen. Conclusion Staphylococcus epidermidiswas the most common bacterial agent isolated on gram staining, and Pseudomonas aeruginosa was the only gram-negative bacillus isolated on gram staining. Fungal isolates were the most common isolates observed on culture, seen in more than half of the IK patients in our study. The majority of patientswho underwent medical management had ulcers healed in two months. The majority of the patients who underwent surgical management had fungal isolates positive.We recommend further research to be conducted in a generalized population, including urban settings, to understand the risk factors, microbiological profile, and treatment outcomes for IK.

Identification of entomopathogenic fungi from insect pests of mango and their efficacy against mango hoppers

Surveys were made in the Sindhudurg and Ratnagiri districts of the Konkan region of Maharashtra, India during 2017-2018 for the collection of mummified insect samples from different mango orchards in order to isolate entomopathogenic fungi. The collected mummified insect samples were brought to the laboratory and incubated on PDA plates. Those samples showing growth on PDA plates were sub-cultured until pure fungus growth was obtained. They were tested for their pathogenicity in the laboratory and 14 samples were found pathogenic to mango hoppers. They were sent to NFCCI, Agarkar Research Institute, Pune for identification. Out of the 14 entomopathogenic samples identified, 7 were from Genus Fusarium, 4 were mixed cultures of Fusarium and Aspergillus, and one sample each from Genus Trichoderma, Mucor and Nigrospora. Studies showed that Fusarium species were the most common entomopathogenic fungi associated with mango pests, especially mango hoppers. Laboratory evaluation of these samples showed that amongst different isolated entomogenus fungi, <i>Fusarium semitectum</i> sample 16(1) was more pathogenic to mango hoppers than other fungal samples. Field evaluation of this sample also proved its efficacy.

Fusarium as potential pathogenic fungus of Ginger (Zingiber officinale Roscoe) wilt disease

The wilt disease of ginger, caused by various Fusarium species, imperils the cultivation of this valuable crop. However, the pathogenic mechanisms and epidemiology of ginger wilt remain elusive. Here, we investigate the association between ginger rhizome health and the prevalence of Fusarium conidia, as well as examine fungal community composition in symptomatic and asymptomatic ginger tissues. Our findings show that diseased rhizomes have reduced tissue firmness, correlating negatively with Fusarium conidia counts. Pathogenicity assays confirmed that both Fusarium oxysporum and Fusarium solani are capable of inducing wilt symptoms in rhizomes and sterile seedlings. Furthermore, Fungal community profiling revealed Fusarium to be the dominant taxon across all samples, yet its relative abundance was significantly different between symptomatic and asymptomatic tissues. Specifically, there is a higher incidence of Fusarium amplicon sequence variants (ASVs) in symptomatic above-ground parts. Our results unequivocally implicate F. oxysporum or F. solani as the etiological agents responsible for ginger wilt and demonstrate that Fusarium is the principal fungal pathogen associated with this disease. These findings provide critical insights for efficacious disease management practices within the ginger industry.

First Report of Fusarium compactum Causing Fusarium Head Blight of Wheat in China.

Fusarium head blight (FHB), a devastating wheat disease caused by several species of Fusarium, threatens global wheat yield and quality (Erenstein et al. 2022). In August 2023, wheat spikes exhibiting clear FHB symptoms were observed in fields in Yunnan, China (24°16'46″ N, 102°29'46″ E), with an incidence rate of approximately 10%. Diseased wheat spikes exhibited a bleached, wilted appearance, with abundant orange sporodochia on the glumes, similar to previous reports (Osborne et al. 2007). Twenty-four symptomatic spikes were collected from a single field, and sporodochia were washed with sterile water to prepare a spore suspension of 1 × 10³ spores/ml, which was inoculated onto potato dextrose agar (PDA) to obtain monosporic cultures. Four reference strains (KUNCC 3418 to KUNCC 3420, and KUNCC 3431) were deposited at the Kunming Institute of Botany Culture Collection, Chinese Academy of Sciences (KUNCC). For species identification, four strains were cultured on PDA and carnation leaf agar (CLA) at 25°C, with incubation under a 12-hour near-UV light/dark cycle on CLA and in complete darkness for 24 hours on PDA. Colonies on PDA grew rapidly, appearing white and loosely flocculent. Abundant pale orange, translucent sporodochia formed on CLA. Sporodochial conidiogenous cells were monophialidic or polyphialidic, subulate to subcylindrical, 9.5-12 μm × 3-3.5 μm. Sporodochial macroconidia were naviculate to fusiform, with an elongate, tapering apical cell and a foot-shaped basal cell, 3-6-septate, 33-67.5 μm × 3.5-5.5 μm. The ITS, tef1-α, rpb1, rpb2, and cam regions were amplified and sequenced using primers ITS1/ITS4, EF-1/EF-2, rpb1-F7/G2R, rpb2-5F2/11aR, and CL1/CL2A, respectively (White et al. 1990; O'Donnell et al. 2000; O'Donnell et al. 2010; Reeb et al. 2004; O'Donnell et al. 1998). These sequences were deposited in GenBank for cam (PP951603 to PP951606), ITS (PP946846 to PP946849), tef-1α (PP719217, PP731572 to PP731574), rpb1 (PP719219, PP737839 to PP737841), and rpb2 (PP719218, PP951607 to PP951609). BLASTn analyses of these sequences showed an identity range of 99.7% to 100% with the epitype strain NRRL 36323 of F. compactum (GenBank: cam = GQ505560, ITS = MH855177, tef-1α = GQ505648, and rpb2 = GQ505826), with base pair matches of 663/665 bp for cam, 488/488 bp for ITS, 641/641 bp for tef-1α, and 892/892 bp for rpb2. Both morphological and BLASTn analyses confirmed these isolates as F. compactum (Leslie & Summerell 2006; Han et al. 2023). Pathogenicity tests were performed by spraying 1 ml of spore suspension (1 × 108 spores/ml) of F. compactum strains onto spikes of the wheat cultivar Yunmai 126 at the flowering stage (n = 9). Controls (n = 9) were treated only with sterile water. Following treatment, the wheat spikes were covered with plastic bags and incubated at 25°C for 10 days. After 14 days, the inoculated spikes turned bleached and dry, showing FHB symptoms, while the wheat spikes in the control treatment remained asymptomatic. The pathogenic fungus re-isolated from all diseased samples was confirmed as F. compactum. It has been frequently reported in association with crown and root rot of wheat, particularly in regions such as Turkey and Iran (Tunali et al. 2008; Besharati et al. 2017). To our knowledge, this is the first report of F. compactum on diseased wheat spikes in China. This finding provides valuable insights into the spread of F. compactum.

Bioprospecting for sustainable and eco-friendly bioproducts: A case study of multi-enzyme production by soil microbes

Microbial multi-enzyme production is a promising research area involving microbes that can simultaneously synthesize numerous enzymes for the degradation of substrates with environmental sustainability and other industrial applications as the focus. During this study, we isolated, screened, and identified some multi-enzyme-producing microbes from three soil sites in Ibadan: Apete Dumpsite (ADS); Botanical Garden University of Ibadan- (BGUI); and Eleyele Cassava Processing Field- (ECPF). Precisely 500 g of soil were collected per point at different depths (0–10, 10–20, and 20–30 cm) and further analyzed. The microbial load and type and enzyme assays were determined. The highest average microbial count (6.9 × 108 CFU/g) was recorded in the ECPF soil sample at 0–10 cm depth, while the lowest microbial count of 3.3 × 105 CFU/g at 20–30 cm soil depth in BGUI. Multi-enzyme-producing microbes were identified phenotypically and molecularly. This study revealed an inverse relationship between microbial community composition and soil depth. Bacterial and fungal genera had higher species richness, biodiversity, and evenness than yeast from all sampled points. With significant amylolytic, proteolytic, lipolytic, cellulolytic, and pectinolytic activities, 22 of the 193 isolates were identified as multienzyme producers. The blasted 16S rRNA and ITS rRNA amplicon sequences compared with sequences in the NCBI gene bank identified Bacillus, Roseomonas, Aeromonas, Phanerochaete, Aspergillus, Fusarium, Trametes, and Rigidoporus species. Results from this study show that topsoils (0–10 cm), rich with organic matter, are good reservoirs of multienzyme-producing microorganisms- applicable for environmental sustainability and in other important industries for waste management, food processing, and biomaterial production.

A-273 Rapid, Portable Invasive Fungal Infection Diagnostic and Candida Antimicrobial Susceptibility Testing

Abstract Background Traumatic wounds are associated with a higher risk of invasive fungal infections (IFI), which lead to a significant increase in amputation or death. Actionable treatment decisions are hampered because true infections can be difficult to differentiate from external wound contaminates, and tissue biopsy and quantification of fungal load is required to determine if treatment is necessary, which currently takes several days. GeneCapture is developing the CAPTURE 60-minute, portable infection identification platform to detect infectious levels of common fungi including the genera Aspergillus, Fusarium, and Scedosporium, the family Herpotrichiellaceae, and the order Mucorales. The company is also pursuing rapid identification and antimicrobial susceptibility testing for Candida species from multiple infection types. Methods This study seeks to determine the Limit of Detection (LoD), sensitivity and specificity of the CAPTURE ID assay for fungal pathogens. Since tissue biopsy samples must be used to assess the presence of IFI in wounds, GeneCapture has developed a manual process for the crude homogenization of muscle tissue to allow this matrix to be used as the starting sample for the ID assay. Mock samples were tested for inclusivity and exclusivity on a series of IFI ID panels against multiple strains of the included fungi, against fungi not yet specifically detected on the panel, and against bacteria that commonly infect wounds. While the LoD for yeasts may be determined in CFU/mL, there is no similar, easy-to-define metric for molds. GeneCapture has developed a quantitative PCR method to detect the single copy beta-tubulin gene to roughly correlate fungal dry mass and nuclei number to assay signal for molds cultured in Potato Dextrose Broth. Determining beta-tubulin copy numbers for extracts from mock samples then allowed detection of the progression of IFI over the course of infection. Lastly, antimicrobial susceptibility testing (AST) was performed on two species of Candida to validate utilizing GeneCapture’s rapid phenotypic AST method for fungal infections. Results To date, the CAPTURE ID panel has been tested against 27 included or excluded strains of fungi or bacteria with 97% sensitivity and 100% specificity. The current LoD for mold organisms varies from approximately 1,000 nuclei for Aspergillus species, to 100,000 nuclei for Fusarium species. Additional work to understand this range is underway. Lastly, we have correctly determined the susceptibility of Candida species using our novel approach within 4-6 hours. Conclusions GeneCapture’s ID and AST technology offer a unique solution to address the increasing prevalence of fungal infections. Our platform can identify the most common fungal components in a wound within 60 minutes of receiving a tissue biopsy sample. Candida infections occur across multiple matrices and rapidly identifying the species of Candida and then determining its phenotypic susceptibility profile will have a large impact on treating these difficult pathogens.

Exploring the rhizosphere of perennial wheat: potential for plant growth promotion and biocontrol applications

Perennial grains, which remain productive for multiple years, rather than growing for only one season before harvest, have deep, dense root systems that can support a richness of beneficial microorganisms, which are mostly underexplored. In this work we isolated forty-three bacterial strains associated with the rhizosphere of the OK72 perennial wheat line, developed from a cross between winter common wheat and Thinopyrum ponticum. Identified using 16S rDNA sequencing, these bacteria were assessed for plant growth-promoting traits such as indole-3-acetic acid, siderophores and ACC-deaminase acid production, biofilm formation, and the ability to solubilize phosphate and proteins. Twenty-five strains exhibiting in vitro significant plant growth promoting traits, belong to wheat keystone genera Pseudomonas, Microbacterium, Variovorax, Pedobacter, Dyadobacter, Plantibacter, and Flavobacterium. Seven strains, including Aeromicrobium and Okibacterium genera, were able to promote root growth in a commercial annual wheat cultivar while strains from Pseudomonas genus inhibited the growth of Aspergillus flavus and Fusarium species, using direct antagonism assays. The same strains produced a high amount of 1-undecanol a volatile organic compound, which may aid in suppressing fungal growth. The study highlights the potential of these bacteria to form new commercial consortia, enhancing the health and productivity of annual wheat crops within sustainable agricultural practices.

Harnessing RNA interference for the control of Fusarium species: A critical review.

Fusarium fungi are a pervasive threat to global agricultural productivity. They cause a spectrum of plant diseases that result in significant yield losses and threaten food safety by producing mycotoxins that are harmful to human and animal health. In recent years, the exploitation of the RNA interference (RNAi) mechanism has emerged as a promising avenue for the control of Fusarium-induced diseases, providing both a mechanistic understanding of Fusarium gene function and a potential strategy for environmentally sustainable disease management. However, despite significant progress in elucidating the presence and function of the RNAi pathway in different Fusarium species, a comprehensive understanding of its individual protein components and underlying silencing mechanisms remains elusive. Accordingly, while a considerable number of RNAi-based approaches to Fusarium control have been developed and many reports of RNAi applications in Fusarium control under laboratory conditions have been published, the applicability of this knowledge in agronomic settings remains an open question, and few convincing data on RNAi-based disease control under field conditions have been published. This review aims to consolidate the current knowledge on the role of RNAi in Fusarium disease control by evaluating current research and highlighting important avenues for future investigation.

Comparative Genomics of Conifer‐Associated Fusarium spp.

ABSTRACTRecent studies have shown numerous Fusarium spp. are associated with symptomatic conifer seedlings in both bareroot and container nursery systems. Some of these species have been found pathogenic to conifer seedlings (e.g., F. avenaceum, F. commune, F. oxysporum, F. solani, and F. verticillioides), but the mechanisms and shared evolutionary history of these conifer pathogenic species have not been well studied in these pathosystems. We compared whole genomes of 17 Fusarium spp. associated with conifer seedlings to elucidate putative shared pathogenicity/virulence gene profiles presumably expressed for roles in causing damping‐off and/or root disease of conifer seedlings. In addition, this work provides draft genomes of conifer‐associated Fusarium spp. and genomes not previously referenced in public databases (e.g., F. lactis, F. fredkrugeri, F. ipomoeae, and F. flocciferum). We identified pathogenicity/virulence genes associated with Fusarium spp. pathogens of conifers including effectors, the secreted in xylem (SIX) genes 2, 4, 9 and 14 and secondary metabolites, and the mycotoxins fumonisin and deoxynivalenol. We conclude that gene profiles are shared within Fusarium species complexes and among closely related Fusarium species complexes; however, these shared profiles are widely distributed across all Fusarium pathogens. These findings highlight potential targets for detecting and/or identifying Fusarium pathogens of conifers, but multiple methods and/or targets will be required depending on the species complexes and clades. More research is needed to determine the roles of expressed pathogenicity/virulence genes and the downstream metabolic products that result in pathogenesis to conifers.

Fusarium species associated with Euwallacea xanthopus in South Africa, including two novel species

ABSTRACT Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) are small wood-boring insects that live in an obligate symbiosis with fungi, which serve as their primary food source. Beetles residing in the genus Euwallacea have evolved a unique association with a clade of Fusarium that falls within the aptly named Ambrosia Fusarium Clade (AFC). The discovery of the invasive polyphagous shot hole borer, E. fornicatus, in South Africa, has heightened awareness of ambrosia beetles and their symbionts in the country. In this study, we investigated the Fusarium symbionts of three species of Euwallacea in South Africa, with a specific focus on those associated with E. xanthopus. Isolations of Fusarium strains from both living and dissected beetles yielded nearly 100 isolates. Using multigene phylogenetic analyses, these isolates were identified as six different Fusarium species. Fusarium hypothenemi and F. euwallaceae have previously been reported from South Africa. Fusarium pseudensiforme and Fusarium AF-6 are new records for the country. The remaining two species are new to science and are described here as F. rufum sp. nov. and F. floriferum sp. nov. Targeted fungal isolation from specific beetle body parts revealed that the AFC species collected were typically associated with the dissected beetle heads and helped us identify the likely nutritional symbiont of E. xanthopus. This study highlights the understudied diversity of fungal associates of ambrosia beetles present in South Africa.

Pathogenicity and Metabolomic Characterization of Fusarium graminearum and Fusarium poae Challenge in Barley under Controlled Conditions.

Barley is the third most important cereal crop in terms of production in Canada, and Fusarium head blight (FHB) is one of the main fungal diseases of barley. FHB is caused by a species complex of Fusaria, of which Fusarium graminearum Schwabe is the main causal species of FHB epidemics in Canada. Field surveys show that two or more Fusarium species often co-exist within the same field or grain sample, and F. poae is reported as another important species in barley. This study aimed to determine the pathogenicity of F. graminearum, F. poae, and a co-inoculation of both species causing FHB in barley. Two susceptible barley cultivars were spray-inoculated at 10 to 14 days after heading. Phenotypic disease severity was rated on a scale of 0-9 at 4, 7, 14, 21, and 28 days after inoculation. There was a significant difference in FHB severity between F. graminearum and F. poae, where infection with F. graminearum produced more severe disease ratings. F. poae generated lower disease ratings and was not statistically different from the control. When heads were co-inoculated with both Fusarium species, the resulting FHB severity was unchanged relative to heads inoculated with F. graminearum only. The ratio of F. graminearum to F. poae genomic DNA was also no different than when heads were inoculated with F. graminearum alone, as quantified with ddPCR using markers specific to each species. The metabolomic analysis of sample extracts showed that F. graminearum-associated metabolites dominated the mycotoxin profile of co-inoculated samples, which corroborated our other findings where F. graminearum appeared to outcompete F. poae in barley. No significant effect on visual FHB disease ratings or fungal DNA detection was observed between the cultivars tested. However, there were some metabolome differences between cultivars in response to the challenge by both F. graminearum and F. poae.

A novel highly antifungal compound ZJS-178 targeting myosin I inhibits the endocytosis and mycotoxin biosynthesis of Fusarium graminearum

Chemical fungicides remain a primary tool for managing Fusarium head blight (FHB) due to the lack of resistant wheat cultivars. In this study, we synthesized 101 2-cyanoacrylate compounds and identified ZJS-178 as particularly effective against Fusarium graminearum (the causal agent of FHB), inhibiting both hyphal growth and conidial germination. Notably, ZJS-178 is specific to Fusarium species, with no impact on other fungi. It also shows no cross-resistance with other groups of fungicides, suggesting a unique mode of action. Mechanistic studies revealed that ZJS-178 targets myosin I in F. graminearum, inhibiting ATPase activity and disrupting endocytosis. Furthermore, ZJS-178 impairs toxisome formation, leading to reduced production of the mycotoxin deoxynivalenol (DON). These findings position ZJS-178 as a promising antifungal agent that could pave the way for developing a novel fungicide to manage FHB and other Fusarium-related diseases.

Effects of fumonisin B1 on gene-specific DNA methylation related to cancer pathways of p53 signalling and PI3K/Akt signalling in human kidney cells

Abstract Fumonisin B1 (FB1), which is emerged by contamination of corn and similar products with Fusarium species, causes a high risk for human and animal health. FB1 shows hepatotoxic, nephrotoxic, neurotoxic, immunotoxic and teratogenic effects. FB1 has also been linked to carcinogenesis processes that are unrelated to genotoxic pathways. Our goal was to investigate the role of gene-specific DNA methylation and expression of tumour suppressor genes in the toxicity of FB1 in human kidney (HK-2) cells. Using array panels, effects of FB1 exposure (10-100 μM) for 24 h on methylation levels of tumour suppressor genes were investigated. ToppGene Suite (Toppfun) portal was used to perform gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) and Reactome enrichment studies. The most of the genes were hypermethylated significantly at 100 μM concentrations of FB1. These results are consistent with the expression results which downregulate the selected genes of CD44, CDKN1A, CDKN2B, CTNNB1, MYC and p16. Functional enrichment analysis further elucidated the molecular mechanisms of FB1 in cancer-related pathways especially p53 signalling and PI3K/Akt signaling. It has been expected that the present study could contribute to the studies on the mechanisms that play a role in FB1 induced carcinogenesis.

Bacillus velezensis CL197: a zearalenone detoxifying strain isolated from wheat with potential to be used in animal production

Zearalenone (ZEA) is a mycotoxin produced by Fusarium species, and cause contamination of food and feed, with impacts in animal production and in food production chain. Effective detoxifying methods, such as biodegradation, are therefore required. This study aimed to isolate microorganisms and screen ZEA detoxifying strains. As a result, 197 microorganisms were isolated, and six were initially selected after colorimetric screening. ZEA (1 µg/mL) was added to culture media, and after 24 h, all six microorganisms were able to degrade ZEA, without the formation of α-ZOL. One isolate eliminated ~ 99% of ZEA and was identified as Bacillus velezensis CL197. ZEA metabolites produced by the bacteria were evaluated, and no metabolites with greater or similar toxicity than ZEA were detected. This strain was applied to swine in vitro digestion, and up to 64% of ZEA was degraded. B. velezensis CL197 significantly degraded ZEA, demonstrating potential to be used as a detoxifying agent in the food production chain as a biocontrol agent.

Identification and molecular detection of the pathogen of Phalaenopsis leaf yellowing through genome analysis.

Moth orchids (Phalaenopsis spp.) are globally popular ornamental flowers. However, effective management strategies for Phalaenopsis leaf yellowing remain elusive, making the disease a challenging obstacle affecting moth orchids at various growth stages. This disease manifests as collar rot, leaf yellowing, leaf abscission, and eventually, plant death. The lack of effective management strategies is likely attributed to a limited understanding of the disease pathogenesis and pathogen dissemination pathways. Fusarium phalaenopsidis sp. nov. was established in this study to stabilize the classification status of Phalaenopsis leaf yellowing pathogens using molecular and morphological features. The genome of the holotype strain was sequenced and assembled, revealing its genome structures. Analyses of virulence-related elements, including transposon elements, secondary metabolite biosynthetic gene clusters, effectors, and secreted carbohydrate-active enzymes, shed light on the potential roles of three fast core chromosomes in virulence. Two species-specific primers were designed based on unique gene sequences of two virulence-related proteins through comparative genomics and BLAST screening. The specificity of these primers was validated using isolates of F. phalaenopsidis, non-target species in the Fusarium solani species complex, other Fusarium species complexes, and saprophytic fungi. These results are intended to accelerate the identification of the pathogens, facilitate the study of disease pathogenesis, and pave the way for elucidating pathogen dissemination pathways. Ultimately, they aim to contribute to the formulation of effective control strategies against Phalaenopsis leaf yellowing.

Cross pathogenicity, host range and molecular characteristics of Fusarium oxysporum species complex populations isolated from tobacco in Jilin Province, China

AbstractFusarium wilt of tobacco (FWT) is a globally significant disease responsible for major losses in tobacco yield and quality. A total of 320 Fusarium oxysporum species complex (FOSC) isolates derived from five tobacco‐growing regions in Jilin province, China, have been confirmed as the predominant pathogens causing FWT, including F. tobaccum, F. cugenangense, F. odoratissimum and F. foetens. In this study, the results indicated that differences in the virulence of the representative isolates from tobacco from the same Fusarium species were significant. Aside from infecting tobacco, the virulence of these representative FOSC isolates differed on chilli and other crops, and they were not pathogenic or were weakly pathogenic to a further 20 crops. Six strains of formae speciales (ff. sp.) of F. oxysporum had the strongest virulence on their original hosts and were not or weakly pathogenic to tobacco. Joint analysis of the pg1‐pg5‐pgx1‐pgx4 genes indicated that 21 isolates of F. cugenangense were divided into four branches, which were clustered with different ff. sp. of F. oxysporum; five isolates of F. foetens were clustered in a branch with f. sp. fragariae, which were not pathogenic to strawberries; six isolates of F. tobaccum and five isolates of F. odoratissimum comprised independent branches and did not cluster with any other f. sp. of F. oxysporum. In sum, none of the FOSC isolates causing FWT in Jilin exhibited tobacco specificity. Our findings further confirmed that FOSC isolates from tobacco could be distinguished into F. tobaccum, F. cugenangense, F. odoratissimum and F. foetens.

Unveiling the Hidden Enemies: Morphological and Molecular Characterization of Pod Rot Pathogens in Groundnut (Arachis hypogea L.) in India

Pod rot of groundnut is a complex disease caused by multiple pathogens causes significant economic losses. Present study was undertaken to know the pathogens associated with the disease. In Chittoor, Andhra Pradesh, roving survey against pod rot of groundnut revealed association of three fungal species: Sclerotium rolfsii, Rhizoctonia bataticola and Fusarium spp. Molecular analysis with modified CTAB method and performing PCR using ITS1 and ITS4 primers yielded DNA bands of 650-700 bp, 550-600 bp, and 500-600 bp for Sclerotium, Rhizoctonia and Fusarium species, respectively. Sequencing of the rDNA ITS region confirmed the identities of the pathogens as Sclerotium rolfsii, Rhizoctonia bataticola, Fusarium solani, Fusarium oxysporum, and Fusarium keratoplasticum, based on similarity with NCBI reference sequences. This study confirms that Sclerotium rolfsii, Rhizoctonia bataticola and Fusarium spp. are the primary causal agents of pod rot disease in Andhra Pradesh.