Fusarium Species Research Articles

Zearalenone contamination in maize, its associated producing fungi, control strategies, and legislation in Sub-Saharan Africa.

The fungal genus Fusarium contains many important plant pathogens as well as endophytes of wild and crop plants. Globally, Fusarium toxins in food crops are considered one of the greatest food safety concerns. Their occurrence has become more pronounced in Africa in recent times. Among the major Fusarium mycotoxins with food and feed safety concerns, zearalenone is frequently detected in finished feeds and cereals in Africa. However, the impact of indigenous agricultural practices (pre- and postharvest factors) and food processing techniques on the prevalence rate of Fusarium species and zearalenone occurrence in food and feed have not been collated and documented systematically. This review studies and analyzes recent reports on zearalenone contamination in maize and other cereal products from Africa, including its fungi producers, agronomic and climate variables impacting their occurrences, preventive measures, removal/decontamination methods, and legislations regulating their limits. Reports from relevant studies demonstrated a high prevalence of F. verticillioides and F. graminearum as Africa's main producers of zearalenone. Elevated CO2 concentration and high precipitation may carry along an increased risk of zearalenone contamination in maize. African indigenous processing methods may contribute to reduced ZEA levels in agricultural products and foods. Most African countries do not know their zearalenone status in the food supply chain and they have limited regulations that control its occurrence.

Individual cytotoxicity of three major type A trichothecene, T-2, HT-2, and diacetoxyscirpenol in human Jurkat T cells

Mycotoxins are toxic, fungal secondary metabolites that contaminate agricultural commodities, food, and feed. Among them, T-2, HT-2, and diacetoxyscirpenol (DAS; the major type A trichothecene) are primarily produced from Fusarium species. These mycotoxins exert numerous toxicological effects in animals and humans, such as dermatotoxicity, haematotoxicity, hepatotoxicity, nephrotoxicity, neurotoxicity, and immunotoxicity. In the present study, human Jurkat T cells were used as a model to investigate apoptotic cell death induced by T-2, HT-2, and DAS. The results showed that T-2, HT-2, and DAS decreased cell viability and increased production of Reactive Oxygen Species in a time- and dose-dependency. Based on their IC50 values, they could be ranked in decreasing order of cytotoxicity as T-2 > HT-2 > DAS. All tested mycotoxins caused DNA fragmentation, up-regulated cytochrome C, caspase 3, and caspase 9 mRNA levels, and down-regulated the relative expression of Bcl-2 and caspase 8. The effects of these trichothecenes on apoptosis were determined based on flow cytometry. At the IC50 concentrations, the percentages of apoptotic cells were significantly higher than for the controls. Taken together, these data suggested that T-2, HT-2, and DAS could induce apoptosis through the mitochondrial apoptotic pathway.

Fusarium sacchari hypovirus 1, a Member of Hypoviridae with Virulence Attenuation Capacity in Phytopathogenic Fusarium Species.

In a survey of mycoviruses in Fusarium species that cause sugarcane Pokkah boeng disease, twelve Fusarium strains from three Fusarium species (F. sacchari, F. andiyazi, and F. solani) were found to contain Fusarium sacchari hypovirus 1 (FsHV1), which we reported previously. The genomes of these variants range from 13,966 to 13,983 nucleotides, with 98.6% to 99.9% nucleotide sequence identity and 98.70% to 99.9% protein sequence similarity. Phylogenetic analysis placed these FsHV1 variants within the Alphahypovirus cluster of Hypoviridae. Intriguingly, no clear correlation was found between the geographic origin and host specificity of these viral variants. Additionally, six out of the twelve variants displayed segmental deletions of 1.5 to 1.8 kilobases, suggesting the existence of defective viral dsRNA. The presence of defective viral dsRNA led to a two-thirds reduction in the dsRNA of the wild-type viral genome, yet a tenfold increase in the total viral dsRNA content. To standardize virulence across natural strains, all FsHV1 strains were transferred into a single, virus-free Fusarium recipient strain, FZ06-VF, via mycelial fusion. Strains of Fusarium carrying FsHV1 exhibited suppressed pigment synthesis, diminished microspore production, and a marked decrease in virulence. Inoculation tests revealed varying capacities among different FsHV1 variants to modulate fungal virulence, with the strain harboring the FsHV1-FSA1 showing the lowest virulence, with a disease severity index (DSI) of 3.33, and the FsHV1-FS1 the highest (DSI = 17.66). The identification of highly virulent FsHV1 variants holds promise for the development of biocontrol agents for Pokkah boeng management.

Mycological Assessment of Selected Swimming Pools of Recreational Centers around the University of Port Harcourt, Nigeria

Aims: This study was carried out to determine the physicochemical properties and mycological safety of four swimming pools within and around the University of Port Harcourt, Rivers State, Nigeria. Study Design: Random sampling design was employed. Place and Duration of Study: Department of Microbiology Laboratory, University of Port Harcourt, between August and October, 2023. Methodology: A total of 8 samples were collected before and after patronage by patrons from 4 swimming pool. Standard methods were employed for the physicochemical parameters such as pH, turbidity and residual chlorine as well as the enumeration for fungi using potato dextrose agar. Results: The pH values ranged from 4.50 to 10.00. The Nephelometric Turbidity Unit ranged from 0.45 to 0.90 NTU while the residual chlorine ranged from 0.36 to 355.00 mg/l. The fungal counts ranged from 1 to 9 cfu/ml, while the isolated species on the basis of cultural morphology and microscopic characteristics were identified as species of Fusarium, Penicillium, Aspergillus, Histoplasma, Rhodotorula, Microsporium and Trichophyton. Conclusion: This study has revealed a potential health risk associated with the use of water of the examined recreational facilities due to none compliance with the WHO standard of < 1 cfu/100ml for fungal and the other parameters, suggesting a public health concern and need for effective interventions.

Internal Transcribed Spacers (ITS) Based Identification of Trichoderma Isolates and Biocontrol Activity against Fusarium oxysporum and Chitinase Activity

Twelve Trichoderma spp. isolated from different locations in Uttar Pradesh, India. Internal transcribed spacer (ITS) amplification and sequencing were used to identify isolates of Trichoderma that showed 99–100% identification with Trichoderma harzianum, Trichoderma asperellum, and Trichoderma longibrachiatum, the three species of Trichoderma. Tests were conducted in Vitro to evaluate the biocontrol potential of Trichoderma isolates against Fusarium species. After seven days of incubation, the isolate TBT6 (T. harzianum) exhibited the greatest antagonism against Fusarium oxysporum, with inhibition rates of 87.1%) by TBT7 (82.2%), and the least amount of inhibition (59.7%) by T. longibrachiatum isolate TBT10. Under field conditions, the antagonistic T. harzianum isolate TBT6 can be employed as a bio-control agent against Fusarium oxysporum. and for the development of formulations based on Trichoderma. Using the dual plate approach, twelve highly antagonistic Trichoderma isolates were selected for chitinolytic activity. Observing the breakdown of chitin substrates, Trichoderma isolates TBT6 was shown to have strong chitinolytic enzyme activity, making it a good candidate for endochitinase gene isolation. Using two particular primers, the genomic DNA of the Trichoderma isolate TBT6 was isolated and amplified.

Impact of Fusarium Species Composition and Incidence on Onion Basal Rot in Northeastern Israel

Fusarium basal rot (FBR) places a significant limitation on Allium production worldwide. The damage caused by the disease can be observed throughout the entire crop cycle. This research aimed to further our understanding of the impact of FBR on the cultivation of onions (Allium cepa) in northeast Israel. It focused on studying the composition and incidence of Fusarium species involved in disease outbursts in two representative fields, one in Galilee (Hula Valley) and the second in the Golan Heights, where the disease incidences reached 8%. Using colony morphology, microscopic taxonomic keys, and molecular methods, a new, unreported Neocosmospora (previously Fusarium solani) species complex (SC, mostly N. falciformis) was discovered as a wildly spread member of the Fusarium pathobiome community. This species complex appeared more generalist in its nature since it was found in all three onion cultivars’ samples. It was also less virulent in seed germination (42–52% higher sprout biomass, p < 0.05) and bulb pathogenicity tests (41–45% less necrotic) than Fusarium acutatum. Whereas the Galilee yellow Orlando (Riverside) onion cultivar bulbs sampled were colonized by Neocosmospora SC (70%) and two other, less abundant species, F. oxysporum f. sp. cepae and F. acutatum (15% each), the Golan Heights field’s Fusarium community showed host specificity. In the Golan Heights field, F. oxysporum f. sp. cepae inhabited the red Ha2 onion cultivar bulbs, whereas F. acutatum colonized the yellow Ha1 cultivar (40% and 50% prevalence along with Neocosmospora SC). A better understanding of the complexity of this disease caused by different Fusarium species and with a divergence in host susceptibility and virulence is critical for developing disease management strategies. Since each Fusarium species reacts differently to pest control treatments, changes in the species composition may require specifically adapted management solutions.

Phorophyte preference of an epiphytic orchid (Dendrobium wangliangii) is independent of orchid mycorrhizal fungi that promote seed germination

Abstract Epiphytism is an example of an obligate interspecific interaction between plants, where a plant species grows on another plant species for physical support. In epiphytic orchids that rely on suitable host tree species (phorophytes) and mycorrhizal fungi for germination and growth, a distinct preference has been observed for particular host tree species. However, the factors driving this host preference remain unclear. In this study, we investigated whether mycorrhizal fungi that promote seedling development determine the preference of phorophytes in the epiphytic orchid Dendrobium wangliangii. First, we identified the preferred host tree species for this orchid. Next, in vitro and in situ germination experiments were conducted to identify potential fungi that promote seed germination. Finally, high‐throughput sequencing was used to assess the distribution of these fungi on both colonized host trees and potential host trees, including individual trees of the host species not yet colonized by the orchid and trees of another species growing in the vicinity of a colonized tree. Dendrobium wangliangii exhibited a preference for trees within the Fagaceae family. Two Fusarium species from the bark of host trees were identified as the primary fungi that promote seed germination. Successful protocorm formation and seedling development were observed exclusively on preferred phorophytes. Fungal community analyses further indicated that both Fusarium spp. occurred on all potential host trees, suggesting that the host preference of this epiphytic orchid is not constrained by the distribution of suitable mycorrhizal fungi. Synthesis: Regarding the epiphytes that depend on mycorrhizal fungi for successful seedling recruitment, we conclude that strong epiphyte–phorophyte associations do not arise from the limited distribution of mycorrhizal fungi but are more likely the result of other factors inherent in the phorophyte environment.

Screening of microscopic fungi isolated from charcoal and wooden samples for Protease production

Proteases, otherwise called proteinases or proteolytic chemicals, have a place with a gathering of hydrolases. Microorganisms are the most well-known wellsprings of business chemicals because of their physiological and biochemical properties. Fungus from charcoal and wooden sample were secluded by sequential weakening agar plate method. The fungal disengages were to begin with evaluation of their capacity to create protease based on zone of clearance on skimmed milk agar plate. The segregates that gave excessive positive consequences in screening were identified as Aspergillus fumigatus, Fusarium species, Mucor recemossus, Penicillin citrium with the aid of inspecting the morphology and Lacto - phenol cotton blue (LPCB) staining procedure. Among those disconnects, Aspergillus fumigatus which constrained from charcoal floor, exhibited the maximum noteworthy protease movement confirming the use of the clean sector across the colony that is brooded at room temperature at a pH of round 7 for a hundred and twenty hours at 28 ˚C. Three fungal disengages chosen by beginning tests were exposed to extracellular protease creation in protease creation medium. The outcomes showed that three fungi could be utilized in the creation of protease compounds and in the upscale for modern creation.

A NADPH-Dependent Aldo/Keto Reductase Is Responsible for Detoxifying 3-Keto-Deoxynivalenol to 3-epi-Deoxynivalenol in Pelagibacterium halotolerans ANSP101.

Deoxynivalenol (DON), primarily generated by Fusarium species, often exists in agricultural products. It can be transformed to 3-epi-deoxynivalenol (3-epi-DON), with a relatively low toxicity, via two steps. DDH in Pelagibacterium halotolerans ANSP101 was proved to convert DON to 3-keto-deoxynivalenol (3-keto-DON). In the present research, AKR4, a NADPH-dependent aldo/keto reductase from P. halotolerans ANSP101, was identified to be capable of converting 3-keto-DON into 3-epi-DON. Our results demonstrated that AKR4 is clearly a NADPH-dependent enzyme, for its utilization of NADPH is higher than that of NADH. AKR4 functions at a range of pH 5-10 and temperatures of 20-60 °C. AKR4 is able to degrade 89% of 3-keto-DON in 90 min at pH 7 and 50 °C with NADPH as the cofactor. The discovery of AKR4, serving as an enzyme involved in the final step in DON degradation, might provide an option for the final detoxification of DON in food and feed.

Unravelling Species Diversity and Pathogenicity of Fusarium spp. Associated with Soybean Leaf and Root in Heilongjiang Province, China.

Soybean (Glycine max L.) holds significant global importance and is extensively cultivated in Heilongjiang Province, China. Soybean can be infected by Fusarium species, causing root rot, seed decay, stem rot, and leaf blight. In 2021 to 2022, a field survey of soybean diseases was carried out in 11 regions of Heilongjiang Province, and 186 soybean leaves with leaf blight symptoms and 123 soybean roots with root rot symptoms were collected. Unexpectedly, a considerable number of Fusarium isolates were obtained not only from root samples but also from leaf samples. A total of 584 Fusarium isolates (416 from leaves and 168 from roots) were obtained and identified as 18 Fusarium species based on morphological features and multilocus phylogenetic analyses with tef1 and rpb2 sequences. Fusarium graminearum and Fusarium sp. 1 in FOSC were the dominant species within soybean leaf and root samples, respectively. Pathogenicity tests were conducted for all Fusarium isolates on both soybean leaves and roots. Results showed that F. graminearum, F. ipomoeae, F. citri, F. compactum, F. flagelliforme, F. acuminatum, and F. sporotrichioides were pathogenic to both soybean leaves and roots. F. solani, F. avenaceum, F. pentaseptatum, F. serpentinum, F. annulatum, and Fusarium sp. 1 in FOSC were pathogenic to soybean roots, not to leaves. To our knowledge, this is the first study to thoroughly investigate soybean-associated Fusarium populations in leaves and roots in Heilongjiang Province.

Impact of Environmental Conditions on the Concentrations of Trichothecenes, Their Glucosides, and Emerging Fusarium Toxins in Naturally Contaminated, Irradiated, and Fusarium langsethiae Inoculated Oats.

Trichothecenes produced by Fusarium species are commonly detected in oats. However, the ratios of the concentrations of free trichothecenes and their conjugates and how they are impacted by different interacting environmental conditions are not well documented. This study aims to examine the effect of water activity (0.95 and 0.98 aw) and temperature (20 and 25 °C) stress on the production of T-2 and HT-2 toxins, deoxynivalenol and their conjugates, as well as diacetoxyscirpenol (DAS). Multiple mycotoxins were detected using liquid chromatography-tandem mass spectrometry from 64 contaminated oat samples. The highest concentrations of HT-2-glucoside (HT-2-Glc) were observed at 0.98 aw and 20 °C, and were higher than other type A trichothecenes in the natural oats' treatments. However, no statistical differences were found between the mean concentrations of HT-2-Glc and HT-2 toxins in all storage conditions analysed. DAS concentrations were generally low and highest at 0.95 aw and 20 °C, while deoxynivalenol-3-glucoside levels were highest at 0.98 aw and 20 °C in the naturally contaminated oats. Emerging mycotoxins such as beauvericin, moniliformin, and enniatins mostly increased with a rise in water activity and temperature in the naturally contaminated oats treatment. This study reinforces the importance of storage aw and temperature conditions in the high risk of free and modified toxin contamination of small cereal grains.

Identification and characterizations of a few species of Fusarium infecting cucumber in greenhouse conditions

One of the most problematic and devastating diseases affecting cucumber production is Fusarium wilt (Cucumis sativus L.). The present study aimed to characterize Fusarium species isolated from three different regions of cucumber fields in Babylon province, Iraq and identify them based on morphological features and phylogenetic analyses. This study showed the presence of Fusarium incarnatum, F. solani and F. oxysporum in cucumber roots. Fusarium species were phylogenetically analyzed based on internal transcribed spacer (ITS) regions. All Fusarium isolates were pathogenic to cucumber cultivars but varied significantly in their growth and pathogenicity toward cucumber seeds during the experiment. F. solani-2 was greater in growth and pathogenicity than all other Fusarium species. In contrast, F. solani-1 was the lowest. The data obtained from morphological and molecular studies sufficiently supported each other, and the phylogenetic trees based on ITS were distinguished. Closely related species and distinctly separated all morphological taxa. These findings are reported for the first time for the cucumber plant in Babylon province. All these ITS sequences showed homologous to those of Fusarium species isolates in the GenBank database with a similarity percentage of 99%. To the best of present knowledge, this is the first molecular record of F. incarnatum on the cucumber plants in Iraq. The study concluded that F. incarnatum was reported for the first time in Iraq and worldwide as a causal agent of wilt disease in cucumber plants. The three species of Fusarium have different pathogenic abilities, highlighting their disease incidence, growth, and pathogenicity.

The potential of soil microbial communities to transform deoxynivalenol in agricultural soils—a soil microcosm study

Infestation of cereal fields with toxigenic Fusarium species is identified as an environmental source for the mycotoxin deoxynivalenol (DON). During rain events, DON may be washed off from infested plants and enter the soil, where microbial transformation may occur. Although some studies showed DON transformation potential of soil microbial communities in liquid soil extracts, these findings can not be transferred to environmental conditions. Accordingly, microbial transformation of DON in soil has to be investigated under realistic conditions, e.g., microcosms mimicking field situations. In this study, we investigated the potential of soil microbial communities to transform DON in six different agricultural soils at two levels (0.5 and 5 µg g–1). The dissipation and the formation of transformation products were investigated in a period of 35 days and compared to a sterilized control. In addition, we measured soil respiration and applied the phospholipid-derived fatty acid (PLFA) analysis to assess whether soil microbial community characteristics are related to the microbial transformation potential. Dissipation of DON in non-sterilized soils was fast (50% dissipation within 0.6–3.7 days) compared to the sterile control where almost no dissipation was observed. Thus, dissipation was mainly attributed to microbial transformation. We verified that small amounts of DON are transformed to 3-keto-deoxynivalenol (3-keto-DON) and 3-epi-deoxynivalenol (3-epi-DON), which were not detectable after 16-day incubation, indicating further transformation processes. There was a trend towards faster transformation in soils with active and large microbial communities and low fungi-to-bacteria ratio.

In Vitro and Ex Vivo Antifungal Activities of Metconazole against the Rice Blast Fungus Pyricularia oryzae.

Rice blast, caused by the filamentous fungus Pyricularia oryzae, has long been one of the major threats to almost all rice-growing areas worldwide. Metconazole, 5-(4-chlorobenzyl)-2, 2-dimethyl-1-(1H-1, 2, 4-triazol-1-ylmethyl) cyclopentanol, is a lipophilic, highly active triazole fungicide that has been applied in the control of various fungal pathogens of crops (cereals, barley, wheat), such as the Fusarium and Alternaria species. However, the antifungal activity of metconazole against P. oryzae is unknown. In this study, metconazole exhibited broad spectrum antifungal activities against seven P. oryzae strains collected from rice paddy fields and the wild type strain P131. Scanning electron microscopic analysis and fluorescein diacetate staining assays revealed that metconazole treatment damaged the cell wall integrity, cell membrane permeability and even cell viability of P. oryzae, resulting in deformed and shrunken hyphae. The supplementation of metconazole in vitro increased fungal sensitivity to different stresses, such as sodium dodecyl sulfate, congo red, sodium chloride, sorbitol and oxidative stress (H2O2). Metconazole could inhibit key virulence processes of P. oryzae, including conidial germination, germ tube elongation and appressorium formation. Furthermore, this chemical prevented P. oryzae from infecting barley epidermal cells by disturbing appressorium penetration and subsequent invasive hyphae development. Pathogenicity assays indicated a reduction of over 75% in the length of blast lesions in both barley and rice leaves when 10 μg/mL of metconazole was applied. This study provides evidence to understand the antifungal effects of metconazole against P. oryzae and demonstrates its potential in rice blast management.

Kingdom Fungi capabilities as materials for design

Background Living organisms such as algae, bacteria, and fungi are used to construct novel materials that offer possibilities for innovation. The article aims to explore mycelial growth and analyze the necessary conditions for its development and durability showing its visual potential as a material to be included in a design project. We have explored the aesthetic and metabolic opportunities offered by some species of filamentous fungi for the integration of this kingdom in the design and production of new materials. Methods Taking processes commonly implemented in biology and adopting them into design processes, we grow filamentous fungi and isolate them into pieces designed to display and ensure their natural development. The process was made through biological science methodology, preparing a PDA culture medium, optimal for the specific growth of these living organisms. The inoculation and incubation of some species of filamentous fungi, mainly of the species Fusarium Proliferatum, was carried out to generate a mother culture, exposing them to stress variables such as changes in temperature, incidence of sunlight, humidity, amount of oxygen received, among others. to generate differences in their morphology and pigmentation. Subsequently, the colonies obtained were transferred to each of the designed and prepared artifacts through spores transferred with a mycological loop. These artifacts were sealed to encapsulate the fungus and wait for the colonization of the piece. Results Perpetuity is evident after nine years of cultivation; the colonies remain in the container preserving their morphological character and the pigmentation presented from the beginning of incubation with a slight variation in the saturation of the colors. Conclusions Depending on the species of fungi used and the stimuli applied by the designer, a wide variety of textures, shapes, and colors can be propitiated, generating new product languages and artifacts where their aesthetic qualities are maintained over time.

Fusarium species central nervous system infection.

Fusarium species are an increasingly important cause of meningitis and invasive disease in immunocompromised patients as well as in otherwise healthy patients as observed in two recent healthcare-associated outbreaks. This review summarizes recently published information on treatment and diagnosis of this infection. Incidence of Fusarium species meningitis and invasive fusariosis are increasing. Molecular techniques are improving the speed of diagnosis. New antifungal agents in development show good in vitro activity against some Fusarium species. New technologies, including cerebrospinal fluid (CSF) filtration, may play a role in treatment of central nervous system (CNS) disease. Due to the continued prime importance of the host immune system in recovery, immunomodulatory treatments may play a role in treatment. The overall incidence of CNS fusariosis is increasing with a continued poor prognosis, but new diagnostic and treatment modalities are in development which may offer improvements.

Cytogenotoxic effect of trichothecene T2 toxin on Allium sativum root tip meristematic cells

Trichothecene T2 is a mycotoxin from the Fusarium species. This research aims to test the effect of the Trichothecene T2 toxin on mitotic index% (M.I.%) and induction of mitotic aberrations by using the Allium sativum (garlic) test system. The toxin concentrations in ppm were 0.00, 0.30, 0.60, 0.90, and 1.20 for 12 hours. The garlic roots were then cut, and mitotic slides were prepared using squash and examined under a light microscope. The results revealed that the mycotoxin has a significant mitodepressive effect at all concentrations compared to the control, and the MI% reduction was proportional to increasing toxin concentration. The highest reduction in mitotic index was observed in the 1.2 ppm treatment. Moreover, this mycotoxin induced and increased the rate of mitotic abnormalities% (MA%) with increasing the mycotoxin concentration. The observed mitotic abnormalities were star-shaped anaphase, sticky metaphase, C-mitosis, sticky anaphase, depolarization, micronuclei, laggard chromosomes, anaphase bridges, and chromosome loss. The least frequently observed abnormality was micronuclei compared to the most frequent aberration, laggard chromosomes. The total mitotic abnormalities significantly increased with increasing the toxin dose concentration. These results suggest that this mycotoxin can inhibit the mitotic activity of the meristematic cells; it is mutagenic and can disrupt the spindle fibers' activity of the dividing cells at all concentrations, especially at higher doses in food. Therefore, the foods must be tested for fungi producing this mycotoxin. Keywords: Mycotoxin; mitodepressive; root tip; spindle fibers; mutagenic

Cytogenotoxic effect of trichothecene T2 toxin on Allium sativum root tip meristematic cells

Trichothecene T2 is a mycotoxin from the Fusarium species. This research aims to test the effect of the Trichothecene T2 toxin on mitotic index% (M.I.%) and induction of mitotic aberrations by using the Allium sativum (garlic) test system. The toxin concentrations in ppm were: 0.00, 0.30, 0.60, 0.90, and 1.20 for 12 hours. The garlic roots were then cut and mitotic slides were prepared by the squash method and examined under a light microscope. The results revealed that the mycotoxin has a significant mitodepressive effect at all concentrations compared to the control and the MI% reduction was proportional to increasing toxin concentration. The highest reduction in mitotic index was observed in the 1.2 ppm treatment. Moreover, this mycotoxin induced and increased the rate of mitotic abnormalities% (MA%) with increasing the mycotoxin concentration. The observed mitotic abnormalities were star-shaped anaphase, sticky metaphase, C-mitosis, sticky anaphase, depolarization, micronuclei, laggard chromosomes, anaphase bridges, and chromosome loss. The least frequently observed abnormality was micronuclei compared to the most frequent aberration, laggard chromosomes. The total mitotic abnormalities significantly increased with increasing the toxin dose concentration. These results suggest that this mycotoxin can inhibit the mitotic activity of the meristematic cells, it is mutagenic and can disrupt the spindle fibers activity of the dividing cells at all concentrations, especially at its higher doses in food. Therefore, the foods must be tested for fungi producing this mycotoxin. Keywords: Mycotoxin; mitodepressive; root tip; spindle fibers; mutagenic

Storage mycotoxin producing fungi in Hungarian sorghum (Sorghum bicolor L. Moench) samples—molecular approach of Fusarium spp.

AbstractThe last few years have been a huge challenge for every farmer in Europe and Hungary because of the increase in hot days and the decrease in precipitation. These facts induced the farmer’s interest in sorghum because it has better stress tolerance than many other cereales, but little is known about mycotoxin-producing fungi, which can infect this crop. Mycotoxins are secondary metabolites of filamentous fungi, and they are not only phytotoxic but also harmful to humans and animals. This study aimed to determine the internal infection caused by Alternaria spp., Fusarium spp., and Aspergillus spp., which are known as mycotoxin-producing fungi in food raw material. In our study in the case of sorghum, the presence of various mycotoxin-producing fungi was detected on Fusarium selective media (Nash and Snyder media), and the results indicate that these genera are present in sorghum grains as potential mycotoxin producers. To determine which Fusarium species is occurring in our sorghum grain samples, a molecular genetic study was performed on isolated fungi using the TEF region primer pairs to identify the occurring Fusarium species. We mainly identified Fusarium proliferatum in our conventional sorghum samples. The results show that the mentioned mycotoxin-producing fungi are in the sorghum grains and may pose a risk to the safety of feed and food because they may produce mycotoxins in the field or while being stored.

Identifying the optimal temperature and water activity conditions of phytopathogenic fungi recovered from Al-Baha province

AbstractFungi are responsible for many plant infections. Indeed, fungi are responsible for most plant spoilage that occurs in the field or in storage, causing symptoms of dieback, leaf spot, rot, rust and wilt. A more serious issue is that fungi produce mycotoxins, which can contaminate crops. Samples of leaf, fruit and root tissues were collected from sick crops, pre- and post-harvest within Al-Baha region. Using molecular markers, twenty fungal isolates were identified that represent eight genera and thirteen species. The most common species were Penicillium spp. (45%), followed by Aspergillus spp. (25%). The remaining 30% were comprised of multiple species (Alternaria alternata, Fusarium oxysporum, Geotrichum candidum, Lasiodiplodia theobromae, Megasporoporia minor and Rhizopus arrhizu). The majority of these isolates are recognised as spoilers of crops and producers of mycotoxins. The study evaluated which temperatures optimised fungal growth. Half of the isolates thrived best at 25 °C; six isolates favoured 30 °C, whilst four isolates grew best at 20 °C. The study also evaluated the optimal water activity (aw) for fungal growth, at four points (0.995, 0.99, 0.90 and 0.85 aw). The isolates were categorised as being either xerophilic, mesophilic or hydrophilic. The majority of isolates (70%) were xerophilic (Aspergillus and Penicillium spp.), 10% were mesophilic (Alternaria alternata and Rhizopus oryzae spp.) and 20% were hydrophilic (Lasiodiplodia theobromae, Geotrichum candidum, Megasporoporia minor and Fusarium oxysporum spp). The information derived from this study will assist in building effective strategies to control these pathogens, minimising crops losses and mycotoxin contamination.