Fusarium Species Research Articles

Mycotoxigenic Fusarium species and zearalenone concentration in commercial maize kernels in northern Ghana.

The fungal genus Fusarium contains many toxigenic pathogens of maize with associated yield losses, reduction of grain quality, and accumulation of mycotoxins in harvested grains. To determine zearalenone (ZEN) concentration and identify the various Fusarium species in commercial maize grains, a survey of 75 maize samples, collected from 11 market centers in the five regions in northern Ghana was identified based on morphological characteristics, sequence analysis of the internal transcribed spacer region, and polymerase chain reaction using species-specific primers. ZEN levels were determined using HPLC. ZEN contamination was recorded in 33.3% of the maize samples, with concentrations ranging from 0.61 to 3.05µg/kg. Based on VERT1/2 and TEF 1-α sequencing, F. verticillioides was the most prevalent species in the studied samples: 40.35% from the Upper East Region, 28.07% from the North East Region, 19.30% from the Upper West Region, 10.53% from the Savannah Region, and 1.75% for the Northern Region. Other fungal species found were F. equiseti and F. solani. A higher number of the Fusarium isolates were found in white maize (609 isolates from 27 samples) compared to yellow maize (225 isolates from 23 samples).

Fusarium and Neocosmospora Species Associated with the Decline of Metasequoia glyptostroboides in China.

During surveys conducted in 2020, severe symptoms associated with death and decline were observed on >30-year-old Metasequoia glyptostroboides (Chinese redwood) trees in the shelter-forests along Yangtze River in Jingzhou city, Hubei province, China. A previous study showed that Phytophthora acerina was one of the causal agents of the decline of the Chinese redwood. In this study, a total of 147 fungal isolates were obtained from the diseased roots and xylem of trunks of declining M. glyptostroboides trees. Through morphology and multi-locus phylogenetic analysis, these isolates were identified as eight species belonging to the genera Fusarium and Neocosmospora including F. fujikuroi, F. irregulare, F. odoratissimum, F. reticulatum， N. falciformis, N. keratoplastica, N. solani, and N. tonkinensis. Single inoculation and co-inoculation with P. acerina assays of these Fusarium and Neocosmospora species were then performed to test pathogenicity on three-year-old seedlings of M. glyptostroboides. Lesions (i.e., on seedling stems) caused by species of the genera Neocosmopora and Fusarium were smaller than those caused by P. acerina. Co-inoculation of F. fujikuroi and P. acerina, as well as the co-inoculation of F. reticulatum and P. acerina caused larger lesions than inoculations with P. acerina alone. All these species of Fusarium and Neocosmospora were shown to have the potential to be pathogenic to M. glyptostroboides. This study provided evidence that the decline of M. glyptostroboides in Jingzhou is a disease complex.

Impact of Harvest Delay and Barley Variety on Grain Nutritional Composition and Mycotoxin Contamination

This study investigated the effects of delayed harvesting, varying meteorological conditions, and barley variety on Fusarium spp. infection rates, nutritional composition, and mycotoxin contamination in barley grains. Field experiments were conducted from 2020 to 2022 and involved two barley varieties: ‘Laureate’ for malting and ‘Luokė’ for feed. The results indicated that the dominant Fusarium species isolated were F. avenaceum, F. culmorum, F. poae, F. sporotrichioides, F. tricinctum, and F. equiseti. These tended to increase in number with delayed harvest times and were more prevalent during harvest periods of higher precipitation (p < 0.05). Malting barley had higher starch and lower protein content compared to feed barley (p < 0.05). Delayed harvesting generally increased dry matter, crude fat, and crude ash contents while decreasing crude protein, zinc, and iron contents (p < 0.05). Mycotoxin analysis revealed significant differences under specific weather conditions. HT-2 toxin levels were higher under slightly warmer and wetter conditions during flowering, with harvest conditions similar to the long-term average. Zearalenone levels increased with dry, warm growing seasons followed by rainy harvests. Nivalenol and enniatin levels increased with rainy growing seasons and dry, warm harvests. Deoxynivalenol concentrations did not reach the limit of quantification throughout the study. No consistent trend was observed for higher contamination in any specific barley variety (p > 0.05). The strongest correlations between mycotoxins and nutritional value indicators were observed with less-studied mycotoxins, such as nivalenol and enniatins, which exhibited negative correlations with crude protein (p < 0.01), crude fat (p < 0.05), and zinc (p < 0.01), and positive correlations with crude ash (p < 0.05) and phosphorus (p < 0.01).

A Diagnostic Guide for Fusarium Fruit Rot of Pumpkin and Winter Squash

Fusarium fruit rot caused by Fusarium solani f. sp. cucurbitae is an important postharvest disease impacting the global production and storage of pumpkins and winter squash ( Cucurbita spp.). The pathogen infects fruit through wounds, causing water-soaked lesions that may become sunken, coalesce, and be covered by fine mycelial growth. F. solani is soilborne and can survive long term in soil and plant debris. Storage rots impact several Cucurbita spp. grown for long-term storage. F. solani f. sp. cucurbitae has two races and is the most commonly found Fusarium species infecting cucurbits. Identification includes morphologic and PCR-based methods. This guide outlines taxonomy, symptoms, isolation, and epidemiology and provides methods to identify the pathogen.

Comparative genomics of Fusarium species causing Fusarium ear rot of maize.

Fusarium ear rot (FER), caused by the fungal pathogen Fusarium verticillioides, stands as one of the most economically burdensome and pervasive diseases affecting maize worldwide. Its impact on food security is particularly pronounced due to the production of fumonisins, toxic secondary metabolites that pose serious health risks, especially for livestock. FER disease severity is complex and polygenic, with few resistance (R) genes being identified for use in breeding resistant varieties. While FER is the subject of several breeding programs, only a few studies have investigated entire populations of F. verticillioides with corresponding virulence data to better understand and characterize the pathogenomics. Here, we sequenced and compared the genomes of 50 Fusarium isolates (43 F. verticillioides and 7 other Fusarium spp.) that were used to inoculate a diverse maize population. Our objectives were to elucidate the genome size and composition of F. verticillioides, explore the variable relationship between fumonisin production and visual disease severity, and shed light on the phylogenetic relationships among the isolates. Additionally, we conducted a comparative analysis of the nucleotide variants (SNPs) and the isolates' effectoromes to uncover potential genetic determinants of pathogenicity. Our findings revealed several promising leads, notably the association of certain gene groups, such as pectate lyase, with disease severity. These genes should be investigated further as putative alleles for breeding resistant maize varieties. We suggest that, beyond validation of the alleles identified in this study, researchers validate each phenotypic dataset on an individual basis, particularly if considering fumonisin concentrations and when using diverse populations. Our study underscores the importance of genomic analysis in tackling FER and offers insights that could inform the development of resilient maize cultivars. By leveraging advances in genomics and incorporating pathogen populations into breeding programs, resistance to FER can be advanced.

A comprehensive review of integrated management strategies for damping-off disease in chili

Damping-off disease in chili (Capsicum annum L.) cultivation is a significant global issue, severely affecting seeds, seedlings, and young plants, regardless of the location of cultivation, whether in greenhouses or open fields. Despite chili being a widely popular vegetable used in various cuisines globally, farmers face challenges in meeting the growing demand due to the extensive damage caused by this disease, ranging from 20 to 85%. The shelf life and quality of mature pods are also severely affected. Damping-off disease is mainly caused by soil-borne fungus from the Pythium species, with additional contributions from Phytophthora, Fusarium, and Rhizoctonia species. These pathogens’ adaptability to diverse environmental conditions and resistance to synthetic fungicides make controlling damping-off on a commercial scale challenging. However, integrated disease management has shown promising results as a remedial approach. In this review, we discuss the current state of chili diseases, the nature of the pathogens causing damping-off, the epidemiology of the disease, and various control mechanisms. In this review, we broadly discuss the current state of chili diseases, the nature of the pathogens causing damping-off, the epidemiology of the disease, and various control mechanisms. Furthermore, we highlight the importance and efficacy of integrated disease management techniques, along with future prospects in unexplored areas, such as host–pathogen interaction and sustainable disease control measures. The information in this review aims to assist chili growers in understanding the epidemiology and management of damping-off in chili cultivation.

Fusarium species associated with Bakanae Disease of Rice in Bangladesh.

Bakanae disease has become a serious threat for sustainable rice production in Asian countries including Bangladesh. Fusarium species are important seedborne pathogens that cause bakanae disease of rice. Typical bakanae symptomatic samples were collected through a series of sampling conducted in several districts of Bangladesh for 4 consecutive years from 2019 - 2022. The pathogens were confirmed using morphological characteristics, DNA sequences, and phylogenetic analyses of two genes, namely, translation elongation factor 1-alpha (TEF1-α), and RNA polymerase subunit II (RPB2). A total of 121 Fusarium isolates were recovered from diseased rice samples at different geographical locations. From the phylogenetics analyses of TEF1-α and RPB2 gene sequences coupled with morphological characterization revealed that the collected isolates belonged to five species viz. F. fujikuroi (75.2% isolation frequency), F. incarnatum (17.35%), F. commune (4.95%), F. verticillioides (1.65%), and F. proliferatum (0.82%). Phylogenetic analysis also showed that 28 representative strains were attributed to five species. Finally, four Fusarium spp. F. fujikuroi, F. commune, F. verticillioides and F. proliferatum were found to be pathogenic under virulence assays of the isolates. The pathogenicity test results demonstrated that F. fujikuroi caused typical symptoms of bakanae, leaf elongation and chlorosis, whereas F. proliferatum and F. verticillioides only caused stunting of seedlings and F. commune caused wilt and root rot. F. incarnatum was found to be associated with bakanae disease of rice, however their pathogenicity could not be established. This study provides insight into the diversity and pathogenicity of Fusarium populations associated with bakanae disease in Bangladesh, which will help in formulating effective strategies and policies for better control of the bakanae disease.

First Report of Fusarium falciforme Causing Fusarium Wilt on pepper in Hainan, China.

Pepper (Capsicum annuum L.) is a significant vegetable crop, valued for its nutritional and economic importance (Pang et al. 2023). Pepper cultivation in China accounts for about 8-10% of the total vegetable planting area, contributing an output value of approximately 250 billion yuan. This makes pepper the leading vegetable in terms of both planting area and economic value. In December 2023, a total of 70% disease incidence of Fusarium wilt was observed in a 1200 m² pepper seed breeding base in Sanya City, Hainan Province, China (18°38'60″ N, 109°16'51″ E). Symptoms initially appeared as wilting on upper leaves. Subsequently, the base of the stem started to necrosis, browning, and gradually spreading upward along the stem. As the lesions expanded, the whole plant gradually wilted and died. Ten diseased plants were randomly selected from the most severely affected area (667 m²). Diseased tissues (5 mm²) were subsequently removed from the lesion edges of these plants, surface sterilized in 75% ethanol for 30 s, and rinsed with sterile distilled water three times, finally cultured on potato dextrose agar (PDA) at 25 °C. Six fungal isolates were obtained using the single-spore isolation method (HN-01 to HN-06). Colonies produced white aerial mycelia with apricot pigments in the PDA medium. The spore morphology and size were observed and measured using synthetic nutrient-poor agar (SNA) medium. Macroconidia were hyaline, slightly curved in shape with 3 or 4 septa, measuring 28.6 to 41.4 × 3.2 to 6.2 μm (av. = 34.8 ± 3.32 × 4.6 ± 0.85 um, n = 20). Microconidia were elongated, oval with 0 or 1 septum, and measured 11.2 to 16.8 × 2.6 to 5.8 μm (av. = 13.5 ± 1.47 × 4.12 ± 1.03 um, n = 20). Chlamydospores were spherical, terminal or intercalary, solitary or chain-forming, with diameters ranging from 2.8 to 10.5 um (av. = 5.8 ± 2.31 um, n = 20). For molecular identification, genomic DNA from all six isolates was extracted using the cetyl trimethyl ammonium bromide (CTAB) method, and the internal transcribed spacer of rDNA (ITS), translation elongation factor 1-α (EF1-α), and RNA polymerase II beta subunit (RPB2) regions were amplified and sequenced using the primers ITS1/ITS4, EF-1/EF-2, and RPB2-5F/7cR (White et al. 1990; O'Donnell et al. 2010). The sequences were deposited in GenBank (ITS: PP779839, PP779840, PP779841, PP779842, PP779843, PP779844; EF1-α: PP797138, PP797139, PP797140, PP797141, PP797142, PP797143; RPB2: PP797144, PP797145, PP797146, PP797147, PP797148, PP797149). The sequences of all three genes showed 99 to 100% similarity with Fusarium falciforme and other closely related Fusarium species (ITS: PP735125, EF1-α: OP163897 and RPB2: MF467484). A maximum likelihood phylogenetic tree was constructed based on the ITS, EF1-α, and RPB2 sequences of all isolates, along with other closely related Fusarium species. Based on morphological and phylogenetic characteristics, all isolates were identified as F. falciforme (Xu et al. 2023; Wang et al. 2023). Ten Pepper inbred line A23-41 (5 for the inoculation treatment and 5 for the control) were tested for pathogenicity using three representative isolates: HN-01, HN-02, and HN-03. A total of 20 ul of spore suspension with concentration 106 spores/ml was injected near the soil surface of the stem, while the control treatment was inoculated with 20 μl of sterile water. The plants were placed in a climatic chamber at RH80-90% and 25/20 °C (day/night) after inoculation. The experiment was repeated three times. After 10 days, Inoculated plants stem developed necrosis, browning, while the control group remained asymptomatic. The fungus reisolated from the artificially infected stems was identified through EF1-α and RPB2 sequence analysis as F. falciforme, thus fulfilling Koch's postulates. Fusarium falciforme has been previoulsy reported as causing various diseases on different hosts in several countries, including Korea (Kang et al., 2024), Malaysia (Balasubramaniam et al., 2023), and Mexico (Payán-Arzapalo et al., 2024). To the best of our knowledge, this is the initial report demonstrating that F. falciforme causes Fusarium wilt on peppers in China. The study results can provide the basis for future research on the occurrence, prevention, and management of this disease.

The effects of fumonisin B1 on intercellular communications and miRNA modulations: Non-genotoxic carcinogenesis mechanisms in human kidney cells

Fumonisin B1 (FB1), which is produced by Fusarium species, is one of the most prevalent mycotoxins known to exert several toxic effects, particularly nephrotoxicity. While its genotoxic carcinogenic mechanisms have been extensively studied, its influence on non-genotoxic pathways including intercellular communication and microRNA (miRNA) regulation remain underexplored. The present study investigates the effects of FB1 on gap junctions, miRNA expression profiles, and their relationship in human kidney cells (HK-2 and HEK293). Both cell lines showed increased apoptosis rates at 50 and 100 µM, while FB1 exposure significantly reduced gap junctional intercellular communication (GJIC) and decreased the expression levels of related genes, including Cx43, Cx45, e-cadherin, Cadherin-2, and β-catenin. After FB1 treatments alteration on the regulation of miRNAs including let-7a-5p, miR-125a-5p, miR-222–3p, miR-92a-3p, let-7b-5p, let-7e-5p, miR-21–5p, miR-155–5p, let-7i-5p, let-7d-5p, let-7f-5p, miR-181b-5p, miR-15b-5p, miR-23b-3p, miR-20b-5p, miR-196a-5p miRNAs have been shown. Let-7a-5p was selected among the altered miRNAs to elucidate the relationship between miRNAs and GJIC after FB1 exposure as it is one of the common miRNAs that changes in both cell lines and one of its target genes is Cx45, which is an important gene for GJIC. However, transfection analysis did not show any differences, resulting in Cx45 not being a direct target of let-7a-5p in HK-2 and HEK-293 cells. Through comprehensive analysis, we elucidated that FB1's impact on intercellular signaling cascades and its regulatory role on miRNA expression profiles, offering valuable insights into carcinogenesis beyond traditional genotoxic paradigms. Understanding these mechanisms is crucial for elucidating the mechanisms of FB1-induced toxicity.

Fusarium Species Shifts in Maize Grain as a Response to Climatic Changes in Poland

Maize, along with wheat and rice, is the most important crop for food security. Ear rots caused by Fusarium species are among the most important diseases of maize. The distribution of Fusarium species provides essential epidemiological information for disease management. The effect of weather conditions, climate change and geographic localization on the Fusarium population in Poland was evaluated between 2015 and 2018. Grain samples (n = 233) were collected from hybrids at 16 locations (L1–L16). The differences in altitude between locations ranged from 39 to 243 m above sea level, longitude varied between 15°55′ and 23°12′ E, and latitude spanned from 50°12′ to 54°01′ N. Isolates were identified using molecular techniques. The highest Fusarium species frequency was recorded for 2016 (30.70%) and 2017 (28.18%), and the lowest for 2018 (5.36%). F. verticillioides and F. temperatum were the most frequent. Altitude has an effect on F. vericillioides frequency: F. graminearum showed a negative correlation with both latitude and longitude. In Polish conditions, from silking to harvesting, the number of days with higher precipitation and lower temperatures is associated with an increased frequency of F. verticillioides, F. temperatum, F. graminearum and F. avenaceum. This suggests that the Fusarium presence in Poland is significantly influenced not only by climate change but also by extreme weather changes.

A single-center study on the distribution and shifting trend of infectious keratitis pathogens from 2018 to 2022

Objective: To investigate the pathogen species, composition, and distribution characteristics of infectious keratitis pathogens in Shandong Province and its surrounding areas. Methods: In this cross-sectional study, patients with keratitis who underwent corneal sampling and microbiological culture at the Shandong Eye Hospital from January 1, 2018 to December 31, 2022 were included. Under topical anesthesia, the edge of the lesion was scraped by an experienced physician. The samples were inoculated on blood agar and Sabouraud dextrose agar plates, separately for bacterial and fungal culture and identification. If necessary, the samples were inoculated on a non-nutrient agar medium with Escherichia coli for Acanthamoeba culture. Bacterial isolates were identified using Vitek 2 compact or matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Fungal isolates were identified based on morphological characteristics or sent to a company for sequencing in cases of difficult identification. The epidemiological data of the patients, pathogen species and number (counting as 1 strain if the same strain was isolated from multiple corneal specimens of the same patient), culture positivity rate, and seasonal distribution were recorded. Differences in pathogen positivity rates among different seasons were analyzed using the chi-square test. Results: Among the 4, 024 patients with infectious keratitis during the study period, there were 2 510 males (62.3%) and 1 514 females (37.6%), aged from 46 days to 94 years. Positive microbial culture results were achieved in 2, 363 patients (58.7%), including 906 cases (38.3%) with bacterial positivity, 1 231 cases (52.1%) with fungal positivity, 28 cases (1.2%) with Acanthamoeba positivity, and 198 cases (8.4%) with mixed fungal and bacterial infections. A total of 2 561 strains were isolated, including 1 104 bacterial strains. The most common bacteria were coagulase-negative Staphylococcus spp. (623/1 104, 56.4%), followed by Streptococcus spp. (131/1 104, 11.9%) and Pseudomonas aeruginosa (68/1 104, 6.2%). The most common fungi were Fusarium spp. (634/1 429, 44.4%), followed by Aspergillus spp. (279/1 429, 19.5%) and Alternaria spp. (229/1 429, 16.0%). Bacterial keratitis was more common in summer and autumn, while fungal keratitis was more common in autumn and winter. Conclusions: Among infectious keratitis cases in Shandong Eye Hospital, Fusarium species were predominant fungal pathogens, while coagulase-negative Staphylococcus predominated in bacterial pathogens. Both fungal and bacterial corneal infections showed seasonal variations.

Susceptibility of Aphis craccivora (Hemiptera: Aphididae) to three entomopathogenic Fusarium species

The black aphid (Aphis craccivora) is an insect pest that can cause significant losses to different agricultural crops. Entomopathogenic fungi can be good options for controlling this insect. Fusarium species have shown promising results in the biological control of several agricultural pests, mainly of the order Hemiptera. This study investigated the susceptibility of A. craccivora to 27 Fusarium isolates, distributed among F. sulawesiense (4), F. pernambucanum (6) and F. caatingaense (17). The viability of the conidia of all isolates was assessed by measuring their germination rate. Pathogenicity tests were conducted at 10⁷ conidia/mL, and the best-performing isolate was further tested at different concentrations (10⁴ to 10⁸ conidia/mL). Data were analyzed using ANOVA, Tukey's test at 5 %, and R for calculating lethal times (LT50,90) and lethal concentrations (LC50,90). All isolates had viable conidia with germination rates between 92.67 % and 100 %. Mortality rates ranged from 17.22 % to 90.23 %. F. pernambucanum URM 7559 had the shortest lethal times (LT50 of 2.24 days and LT90 of 4.42 days), followed by F. sulawesiense URM 7555 (LT50 of 2.35 days and LT90 of 4.77 days) and F. caatingaense with LT50 of 3.93 days for URM 6784 and LT90 of 8.27 days for URM 6807. The three Fusarium species tested, especially F. pernambucanum, showed promise in the biological control of A. craccivora. Although the results are promising, additional studies are needed to evaluate the safety, field efficacy and environmental impacts of Fusarium use, focusing on the interaction with the agricultural ecosystem and the risks to non-target organisms.

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.

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.