Search Results (56)

The soil-borne fungi, Setophoma terrestris and Fusarium spp., are often associated with pink root, although the etiology of the disease remains doubtful. While recognized as the primary inoculum, studies show conflicting views on the formation of chlamydospores and microsclerotia in Setophoma. Therefore, this study aims to clarify the etiology of the pink root of garlic and onion and the formation of chlamydospores and microsclerotia in Setophoma. The isolates were obtained from symptomatic tissues of garlic, leeks, brachiaria, onions, chives, and maize collected from seven different states in Brazil. Representative isolates were selected for pathogenicity tests. Sequence comparison of the tubulin gene showed Setophoma (n = 50) and Fusarium clades (n = 25). Garlic and onion plants inoculated with Setophoma showed pink root symptoms, while plants inoculated with different Fusarium isolates remained asymptomatic. Multigene analysis of pathogenic isolates confirms that only Setophoma terrestris causes pink root in garlic and onion. In addition, brachiaria, chives, and leeks are newly identified hosts of this pathogen in Brazil. To our knowledge, the main sources of primary inoculum of the disease are chlamydospores, pycnidia, colonized roots of garlic, onion, and plant debris of susceptible crops. The new information obtained in this study will be fundamental for researchers in the development of genotypes that are resistant to pink root and will help the efficient management of the disease. Full article

Fungal chlamydospores are asexual spores formed by fungi under adverse conditions and could be used in biological pretreatment for biogas projects fed by lignocellulosic substrates. In this study, Trichoderma viride (Tv) chlamydospores were used as the pretreatment agent to enhance the methane yield of spent mushroom substrates (SMSs). Lignocellulosic composition, methanogenesis performance, and anaerobic microbial communities were investigated for different Tv pretreatment durations (0 h, 12 h, 24 h, 48 h, 96 h, and 192 h). The results showed that the optimal Tv pretreatment duration was 24 h, and the cumulative methane yield reached 173.4 mL/gVS, which was 16.8% higher than that of the control. A pretreatment duration longer than 48 h was not conducive to methanogenesis. Sequencing analysis of anaerobic microbial communities showed that the pretreatment duration was directly proportional to the relative abundance of Tv at the beginning of digestion. When the initial Tv abundance was higher than 50%, Trichoderma became the absolute dominant fungus with an abundance higher than 97% in fungal communities in the later stage of digestion. The correlation network among fungi, bacteria, and archaea showed that Tv was directly related to 11 genera, and through these taxa, Tv affected 58% of the taxa in the whole microbial network. Cost accounting showed that Tv pretreatment has a net income of 45.5 CNY/1000 kg SMS, and is a promising technology. This study provides important guidance for the use of fungal chlamydospores in pretreatment and also promotes the understanding of fungi in anaerobic digestion. Full article

Equine farming faces growing challenges with helminthoses, aggravated by the indiscriminate use of anthelmintics without technical criteria. This practice favors resistance to these drugs, generates residues in animal products, compromises food safety and human health, and, when excreted in large quantities, negatively impacts environmental health by affecting invertebrates and fecal microorganisms. This highlights the importance of the One Health approach. A promising alternative is biological control with nematophagous or helminthophagous fungi such as Duddingtonia flagrans, Pochonia chlamydosporia, Arthrobotrys oligospora, Monacrosporium thaumasium, Mucor circinelloides and Purpureocillium lilacinum. Due to their different mechanisms of action, ovicidal and predatory fungi, when used together, can act in a complementary and synergistic way in the biological control of helminths, increasing their effectiveness in reducing parasitic infections. The use of these fungi through biosynthesized nanoparticles from fungal filtrates is also emerging as a new approach to nematode control. It can be administered through feed supplementation in commercial formulations. The aim of this review is to explore the use of helminthophagous fungi in the control of helminthiases in horses, highlighting their potential as a biological alternative. It also aims to understand how these fungi can contribute effectively and sustainably to parasite management in horses. Full article

Fusarium wilt, caused by Fusarium oxysporum f. sp. cubense (Foc), is recognized as one of the most devastating diseases affecting banana cultivation worldwide. In India, Foc extensively affects Malbhog banana (AAB genomic group) production. In this study, we isolated 25 Foc isolates from wilt-affected Malbhog plantations inIndia. A pathogenicity test confirmed the identity of these isolates as Foc, the primary causative agent of wilt in bananas. The morpho-cultural characterization of Foc isolates showed large variations in colony morphological features, intensity, and pattern of pigmentation, chlamydospores, and conidial size. The molecular identification of these isolates using Race1- and Race4-specific primers established their identity as Race1 of Foc, with the absence of Tropical Race 4 of Foc. For a more comprehensive understanding of the genetic diversity of Foc isolates, we employed ISSR molecular typing, which revealed five major clusters. About 96% of the diversity within the Foc population indicated the presence of polymorphic loci in individuals of a given population evident from the results of Nei’s genetic diversity, Shannon’s information index, and the polymorphism information content values, apart from the analysis of molecular variance (AMOVA). The current findings provide significant insights toward the detection of Foc variants and, consequently, the deployment of effective management practices to keep the possible epidemic development of disease under control along the Malbhog banana growing belts of northeast India. Full article

This study evaluated the effectiveness of Duddingtonia flagrans chlamydospores and an Artemisia cina hexane extract in reducing Haemonchus contortus fecal egg counts and larvae in periparturient ewes. This study involved five groups of four ewes: a control group, an ivermectin group, an A. cina oral extract group, a D. flagrans group, and a combined treatment group. Treatments began two weeks before delivery, with ivermectin administered 15 days before delivery. Fecal samples were collected every fifteen days to estimate parasite egg counts per gram of feces (EPG) and assess larvae reductions. The results showed very low EPG values for ivermectin and D. flagrans treatments (175 and 150, respectively). The control and combined treatment groups had EPG values rise to 3000 and 4100 by day 15. The EPG values for the A. cina group reached 850 and 533 in later samplings. Throughout the study, the D. flagrans and A. cina groups maintained low EPG values, with the highest recorded values being 50 and 0, respectively. All treatments significantly reduced the larvae in the fecal cultures: D. flagrans (97.4% reduction), ivermectin (91.4%), Artemisia cina (89.9%), and the combined treatment (84.3%). Full article

Black root rot is a dangerous disease affecting many crops. It is caused by pathogens formerly known as Thielaviopsis basicola and then reclassified as two cryptic species, Berkeleyomyces basicola and B. rouxiae. The aim of this study was to perform species identification, morphological characterization, and pathogenicity tests for fungal isolates obtained from tobacco roots with black root rot symptoms in Poland. DNA sequences of the three regions (ITS, ACT, MCM7) were highly similar to the sequences of B. rouxiae deposited in the NCBI database. Phylogenetic analysis confirmed the assignment of the obtained isolates to this species. The cultures of four representative isolates (namely OT2, OT3, WPT7, WPT8) showed a similar structure and gray/brown color of the mycelium, although their growth rate varied from 3.8 to 5.1 mm/day depending on the isolate. The sizes of the endoconidia and chlamydospores showed a considerable variation, although they fit within ranges previously described for B. rouxiae. Pathogenicity tests performed on young tobacco plants grown in the inoculated peat substrate revealed differences among the four isolates. WPT7 demonstrated the lowest level of aggressiveness for tobacco. In contrast, the remaining three isolates caused severe disease symptoms and significantly reduced shoot and root dry weights of the susceptible cultivar Virginia Joyner. A parallel pathogenicity test performed on cultivar VRG 10TL confirmed the effectiveness of black root rot resistance derived from Nicotiana debneyi. Full article

Parsnips (Pastinaca sativa) are a speciality UK crop with an economic value of at least 31M GBP annually. Currently, the major constraints to production are losses associated with root canker disease due to a range of fungal pathogens, among which Itersonilia pastinacae is of most concern to growers. With limited research conducted on this species, this work aimed to provide a much-needed characterisation of isolates from across the UK, continental Europe, and New Zealand. Previously, up to four separate Itersonilia species have been proposed based on the formation of chlamydospores and host specificity: I. pastinacae, I. perplexans, I. pyriformans, and I. pannonica. However, Itersonilia spp. isolates principally from parsnip, but also from a range of other hosts, which were found to infect both parsnip roots and leaves in pathogenicity tests. In growth rate assays, isolates were found to grow at temperatures of 0–25 °C and produce both chlamydospores and ballistospores across the same range of temperatures, although chlamydospore production was found to decrease as temperature increased. Following whole genome sequencing, specific primers were designed for the molecular characterisation of the isolates using six housekeeping genes and three highly variable functional genes. Phylogenetic analysis separated isolates into two and six clades, respectively, but the grouping was not associated with hosts or locations. Based on the results of this research, there was no evidence to support more than a single species of Itersonilia among the isolates studied. Full article

Black root rot (BRR) and Verticillium wilt of cotton are caused by soilborne Berkeleyomyces rouxiae and Verticillium dahliae, respectively, and can individually cause yield loss of a 10–50% in New South Wales (NSW). Both diseases were first detected in a northern valley of NSW but are now present across the state. ‘Come Clean Go Clean’ is a widely practiced biosecurity measure used to minimize the risk of further introducing the pathogens from one field to another by restricting the movement of soil-contaminated farm equipment and machinery. We rely on cleaning agents to effectively wash down and decontaminate the equipment and machinery. In this study, we examined 12 locally available, commercial disinfectants for their efficacy against B. rouxiae and V. dahliae reproductive structures with and without soil contamination of 10% (w/v). We found a significant interaction between pathogens, disinfectants, and soil amendment (p < 0.01). The germination of B. rouxiae chlamydospores and endoconidia in both the presence and absence of soil contamination was completely suppressed even after a short 10 sec exposure to 70% ethanol and 25% bleach. Both 70% ethanol and bleach were highly lethal at 10 sec exposures in similar assays against V. dahliae microsclerotia and conidia. Some other commercial products were able to reduce the germination rate significantly but did not completely kill microsclerotia and conidia even after 30 min of exposure. The lethal effect against B. rouxiae and V. dahliae warrants further exploration of both 70% ethanol and bleach to improve their field applications. Additionally, the efficacy of most tested commercial disinfectants was time-dependent; however, this is not recommended on the labels for their effectiveness. This study provides an additional integrated disease management option aiming to limit the spread of the pathogens. Full article

Nematode-trapping (NT) fungi are a major resource for controlling parasitic nematodes. Arthrobotrys flagrans, as a typical NT fungus, can capture nematodes by producing three-dimensional nets. The APSES transcription factor Swi6 plays a vital role in fungal growth and the pathogenicity of pathogens. In this study, we characterized AfSwi6 via gene disruption using the homologous recombinant method and transcriptome sequencing. Knockout of the AfSwi6 gene caused defects in mycelial growth, trap formation and pathogenicity, chlamydospore production, and stress response. Moreover, the transcriptome data indicated that AfSwi6 was related to DNA repair, stress response, and plasma membrane fusion. The result showed that AfSwi6 has a significant effect on trap development and chlamydospore production in A. flagrans. Full article

Candida auris is an emerging, multidrug-resistant yeast that causes systemic infections, mainly in hospitalized or immunosuppressed patients. This pathogen has a high mortality and morbidity rate. This study aims to evaluate the antifungal potential of micafungin (MICA) encapsulated in a nanoemulsion (NEM) against four clades of C. auris and other non-C. auris species. The antifungal potential of MICA and NEM was evaluated by determining mature biofilm inhibition (0.78–50 µg/mL). The antifungal activities of MICA and NEM (5.92 mg/Kg) were evaluated using an in vivo model of Galleria mellonella. The results showed that NEM intensified the antibiofilm action of MICA, especially in 48 h mature biofilms. In vivo results displayed a higher effectiveness of NEM against all clades of C. auris tested, inhibiting the fungal load in the hemolymph and tissues of G. mellonella with a difference of 3 log10. In addition, C. auris infection caused granulomas surrounded by hemocytes, mainly at the lower and upper ends. Conversely, C. albicans developed pseudohyphae, biofilms, filaments, and chlamydospores. In conclusion, encapsulation of MICA in a nanoemulsion enhances its antifungal activity against mature biofilms of C. auris. This strategy may be considered a therapeutic approach for the control of infections and the dissemination of this new global health threat. Full article

Fatsia japonica plays an important role as a commonly used plant in urban landscaping. From 2022 to 2023, a root rot infestation was observed that caused extensive wilting of Fatsia japonica without leaf shedding and eventual death of the plant, severely reducing the ornamental qualities of the plant as well as the vigor of its growth. Fusarium species were isolated from the roots of the affected plants, exhibiting abundant and dense yellow mycelial colonies that proliferated radially from the center of the Petri dishes. Morphological examinations revealed the presence of falciform macro- and microconidia consistent with Fusarium, as well as chlamydospores characterized by their thick walls. For further identification, the amplification and sequencing of the ITS, TEF1 alpha, and RPB2 alpha genes were performed. Finally, healthy Fatsia japonica plants were inoculated with a spore suspension of the pathogen, to confirm that the disease symptoms were compatible with naturally occurring infection. Fusarium vanettenii was identified as the causative agent of Fatsia japonica root rot. To the best of our knowledge, this is the first report of F. vanettenii causing root rot of Fatsia japonica in China. Full article

Background: Relapse of Candida albicans urinary tract infection (UTI) is frequent despite appropriate treatment, as commonly used antifungals such fluconazole and flucytosine are only fungistatics. To improve treatment of Candida UTI and decrease relapses, understanding the long-term metabolic activity and survival of C. albicans in urine containing antifungals at minimal inhibitory concentration (MIC) is needed. Methods: we monitored the survival, metabolic activity and consumption of glucose and proteins by C. albicans using conventional methods and isothermal microcalorimetry (IMC). We also investigated the influence of dead Candida cells on the growth of their living counterparts. Results: For 33 days, weak activity was observed in samples containing antifungals in which C. albicans growth rate was reduced by 48%, 60% and 88%, and the lag increased to 172 h, 168 h and 6 h for amphotericin, flucytosine and fluconazole, respectively. The metabolic activity peaks corresponded to the plate counts but were delayed compared to the exhaustion of resources. The presence of dead cells promoted growth in artificial urine, increasing growth rate and reducing lag in similar proportions. Conclusions: Even with antifungal treatment, C. albicans relapses are possible. The low metabolic activity of surviving cells leading to regrowth and chlamydospore formation possibly supported by autophagy are likely important factors in relapses. Full article

Several strategies promote phyllosphere colonization by soil-born Trichoderma plant-beneficial strains. One of these strategies is foliar spraying with suspensions containing large amounts of chlamydospores—spores with thick cell wall structures that make them highly resistant to harsh environmental conditions. Trichoderma biomass was produced by cultivation on a cornmeal medium and compared with the biomass produced on potato dextrose broth by microscopic and thermogravimetric analyses. The analyses revealed increased chlamydospore content and thermostability in the fungal biomass produced on the corn meal medium. The Trichoderma suspension rich in chlamydospores was sprayed on bitter gourd (Momordica charantia) leaves at two inoculant concentrations, 10⁶ and 10⁸ ufc/mL. The effect of these treatments on the plant physiological parameters, leaf photosynthetic pigments, polyphenol and flavonoid contents, antioxidant activities of the leaves and fruits, and yield was compared to the control (plants sprayed with water) and to the experimental treatment involving spraying with 10⁸ ufc/mL of propagules produced in potato dextrose broth. The effect of chlamydospore-rich suspensions on plant physiological parameters was more pronounced and long-lasting compared with the other treatments. The treatment with chlamydospore-rich suspension enhanced the accumulation of polyphenols and flavonoids in the leaves (by 17% and 50%, respectively) and fruits (by 18% and 31%, respectively) and increased the antioxidant activity. The Trichoderma treatment increased the yield by +25.33–53.07%. The application of the foliar treatment with Trichoderma suspensions did not modify the cytocompatibility of the extracts from the fruits determined on the L929 cells. Full article

This work carried out research to determine the possibilities of using graphene oxide to provide wood with new functional features. With the saturation parameters used and working liquid with a concentration of 0.004% graphene oxide, the retention of the nanomaterial in wood was 0.25 kg/m³. The presence of graphene oxide increased the crystallinity of the wood to 64% (compared with 57% for unmodified wood). The TG/DTG spectra of wood impregnated with graphene oxide and the control wood indicated that the initial weight loss of the samples observed at a temperature of 100 °C was similar and amounted to less than 4%. A second mass loss was observed in a temperature range of 270 to 380 °C. The mass loss in this temperature range reached 70% and was similar in the test and control samples. Wood modified with graphene oxide showed increased thermal stability in a temperature range of 360 to 660 °C compared with native wood. Given the results obtained, there were no statistically significant differences in the water absorption of modified or control wood. The presence of low concentrations of graphene oxide in the culture medium did not inhibit the growth of the fungus Trichoderma viride; however, a decrease in the growth activity of mycelial hyphae was observed with an increasing concentration of nanomaterial in the medium. It has been reported that graphene oxide, as a stress factor, initiates changes at the cellular level, characterized by the formation of structures called chlamydospores by the body. Full article

Bakanae is one of the important diseases of rice in Bangladesh that causes substantial yield loss every year. We collected thirty isolates of Fusarium spp. from bakanae-infected rice plants from different agroecological zones of Bangladesh and investigated the variations in cultural and morphological characteristics and pathogenicity. Diversity was found in cultural characteristics, viz., colony features, phialide, chlamydospore formation, shape, and size of macro- and microconidia. Three variants of Fusarium species such as F. moniliforme, F. fujikuroi, and F. proliferatum were identified on PDA media based on their cultural and morphological characteristics. Isolate FM10 (F. moniliforme) exhibited the highest disease aggressiveness in developing elongated plants (26.50 cm), the highest number of chlorotic leaves (5.75), and a lower germination percentage. We evaluated different bioagents against the virulent isolate of F. moniliforme to develop a rice bakanae disease management approach. Four bioagents, viz., Trichoderma spp., Bacillus subtilis, Pseudomonas fluorescens, and Achromobacter spp., were evaluated for growth suppression of F. moniliforme. Among the bioagents, Achromobacter spp. and B. subtilis (BS21) showed 73.54% and 71.61% growth suppression, respectively. The investigation revealed that the application of Achromobacter spp. and B. subtilis (BS21) would be a potential candidate for effective and eco-friendly management of the bakanae disease of rice. Full article