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In the presented study, isolation of bacterial strains, viz., Pantoea agglomerans, Priestia megaterium and phytopathogenic micromycetes that cause damage and eventually death of grape crops, came from a 10 to 15-year-old vine plantation. A Pantoea agglomerans gram-negative bacillus facultative and anaerobic bacterium strain achieved isolation from grape plants, with its morphological characteristics studied. Bacterial strains with antifungal activities against phytopathogenic micromycetes succeeded in their identification. Bacterial isolates collected from the vines underwent screening for their growth properties. It was apparent that Pantoea agglomerans actively grew wheat coleoptiles by 2.6 mm and maize coleoptiles by 2.3 mm compared with the control. Observable evidence also showed that sorghum coleoptile actively grew by 1.7 mm compared with the control treatment by 2.9 mm. The 26 Aspergillus sp., 23 Penicillium sp., 25 Fusarium sp., 30 Alternaria sp., and five Curvularia sp. phytopathogenic micromycetes belonging to the genus were notable. Bacterial strains isolated from the vine showed the highest antifungal activity against micromycetes belonging to the genus Penicillium and reduced the radius of phytopathogenic growth to 47-54 mm. Compared with micromycetes belonging to the genus Fusarium, it was also apparent that the pathogen reduced the growth radius to 27-35 mm. Isolation of phytopathogenic micromycetes from the vine allows early detection and prevention of grape diseases. Based on these studies, the identification of antifungal activity of the bacterial strains isolated from the vine and the presence of phytohormones in the culture fluid indicated that it is an essential and environmentally friendly biological tool in the cultivation of grapes for human consumption. [ABSTRACT FROM AUTHOR]

The excessive proliferation of Pontederia crassipes poses serious threats to freshwater bodies in many parts of the world. This aquatic weed causes severe ecological and economic losses worldwide. In South Africa, research has focused on the release of insect biological control agents associated with P. crassipes, with eight insect agents, and only one fungus released to date. Fungi have been explored as a safe method for the management of P. crassipes, due to their ability to cause and spread a vast array of weed diseases. In this study, naturally occurring fungi associated with P. crassipes were surveyed, isolated, and identified using culture methods to determine their prevalence and pathogenicity to P. crassipes. Forty-two fungal isolates were morphologically identified as belonging to genera Alternaria, Fusarium, Epicoccum and Colletotrichum. Subsequently, molecular techniques and bioinformatics confirmed the identity of the fungi that were most pathogenic as Fusarium incarnatum, Fusarium oxysporum and Fusarium equiseti. In whole plant bioassays, these fungi caused 68, 63 and 54% disease infection, respectively, by the end of six weeks, and thus may be considered for future developments into bioherbicides. Moreover, F. incarnatum exhibited 97% disease severity during in vitro assays. This study is also the first to report F. incarnatum occurrence on P. crassipes in South Africa. [ABSTRACT FROM AUTHOR]

This paper describes the mycotoxins produced by fungi from the genera Fusarium, Penicillium, Aspergillus, Claviceps and other types of molds, their characteristics and importance. Mycotoxins are secondary fungi metabolites that serve as a defense mechanism in stressful conditions. Several hundred mycotoxins have been identified so far, and the most significant in terms of danger to human health and animals are aflatoxins, ochratoxin A, patulin, fumonisin, zearalenone and nivalenol/deoxynivalenol produced by toxigenic fungi from the genera Penicillium, Aspergillus, Claviceps, Stachybotris and Fusarium. Moisture and temperature are two factors that have a crucial influence on the development of the fungus and the synthesis of toxins. It is estimated that approximately 25% of agricultural crops are infected with fungi. Consequently, foods can also be contaminated with mycotoxins. By treating the stored grain with various chemicals, and in recent years, using environmentally friendly fungicides, the synthesis of mycotoxins is being prevented and the development of mycotoxicogenic fungi is being controlled. The mycotoxicosis can occur directly through the consumption of infected food, inhalation and skin contact, or indirectly through animals that eat contaminated feed. Mycotoxins have a pathological effect primarily on liver. Some mycotoxins also interfere with cellular protein synthesis, causing hypersensitivity and extreme immunodeficiency. Despite mycotoxins being resilient and remaining stable while undergoing chemical and thermal food processing, methods such as applying good hygiene and production practices from field to table can reduce their occurence.

Plants interact with a great diversity of microorganisms or insects throughout their life cycle in the environment. Plant and insect interactions are common; besides, a great variety of microorganisms associated with insects can induce pathogenic damage in the host, as mutualist phytopathogenic fungus. However, there are other microorganisms present in the insect-fungal association, whose biological/ecological activities and functions during plant interaction are unknown. In the present work evaluated, the role of microorganisms associated with Xyleborus affinis, an important beetle species within the Xyleborini tribe, is characterized by attacking many plant species, some of which are of agricultural and forestry importance. We isolated six strains of microorganisms associated with X. affinis shown as plant growth-promoting activity and altered the root system architecture independent of auxin-signaling pathway in Arabidopsis seedlings and antifungal activity against the phytopathogenic fungus Fusarium sp. INECOL_BM-06. In addition, evaluating the tripartite interaction plant-microorganism-fungus, interestingly, we found that microorganisms can induce protection against the phytopathogenic fungus Fusarium sp. INECOL_BM-06 involving the jasmonic acid-signaling pathway and independent of salicylic acid-signaling pathway. Our results showed the important role of this microorganisms during the plant- and insect-microorganism interactions, and the biological potential use of these microorganisms as novel agents of biological control in the crops of agricultural and forestry is important. [ABSTRACT FROM AUTHOR]

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ZnO-based nanomaterials have high antifungal effects, such as inhibition of growth and reproduction of some pathogenic fungi, such as Fusarium sp., Rhizoctonia solani and Macrophomina phaseolina. Therefore, we report the extracellular synthesis of ZnONPs using a potential fungal antagonist (Trichoderma harzianum). ZnONPs were then characterized for their size, shape, charge and composition by visual analysis, UV–visible spectrometry, X-ray diffraction (XRD), Zeta potential, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The TEM test confirmed that the size of the produced ZnONPs was 8–23 nm. The green synthesized ZnONPs were characterized by Fourier transform infrared spectroscopy (FTIR) studies to reveal the functional group attributed to the formation of ZnONPs. For the first time, trichogenic ZnONPs were shown to have fungicidal action against three soil–cotton pathogenic fungi in the laboratory and greenhouse. An antifungal examination was used to evaluate the bioactivity of the mycogenic ZnONPs in addition to two chemical fungicides (Moncut and Maxim XL) against three soil-borne pathogens, including Fusarium sp., Rhizoctonia solani and Macrophomina phaseolina. The findings of this study show a novel fungicidal activity in in vitro assay for complete inhibition of fungal growth of tested plant pathogenic fungi, as well as a considerable reduction in cotton seedling disease symptoms under greenhouse conditions. The formulation of a trichogenic ZnONPs form was found to increase its antifungal effect significantly. Finally, the utilization of biocontrol agents, such as T. harzianum, could be a safe strategy for the synthesis of a medium-scale of ZnONPs and employ it for fungal disease control in cotton. [ABSTRACT FROM AUTHOR]

Common bean root microbiome was used to research for potential biocontrol agents of phytopathogenic fungi as Fusarium sp., Macrophomina sp., and Alternaria sp. causal agents of root rot disease on host plants. Therefore, a bacterial collection of 90 endophytic and rhizospheric isolates was established from field-grown common bean plants in Tunisia and screened for their antifungal activity against pathogenic fungal strains. Antifungal activity was checked at biochemical and genetic levels. Twelve bacterial strains exhibited up to 71% of inhibition of the three pathogenic strains of Fusarium sp., Macrophomina sp., and Alternaria sp. Biocontrol assays conducted under controlled conditions demonstrated that Bacillus amyloliquefaciens, Bacillus halotolerans, Bacillus velezensis, Agrobacterium fabrum, and Pseudomonas lini displayed the highest protective effect on common bean cv. Coco blanc. These bacterial strains were associated with significant plant growth promotion up to 217%, in comparison with control plants. Biochemical analysis of the antagonistic and plant growth promoting activity revealed the production of xylanases, chitinases, siderophore, hydrogen cyanide, phosphate-solubilizing activity, and the production of indole-3-acetic acid, particularly in Bacillus spp. strains. Polymerase chain reaction revealed the presence of lipopeptide biosynthetic genes encoding surfactin, iturin, bacillomycin, and fengycin. The study unveiled that common bean root microbiome contains potential bacterial strains that exhibit efficient biocontrol activity of Fusarium sp., Macrophomina sp., and Alternaria sp., and act as plant growth promoters. Considering various plant growth promoting and biocontrol traits, the study showed the superiority of the Bacillus spp. strains among different common bean root microbiomes. [ABSTRACT FROM AUTHOR]

Abstract Endophytic and phytopathogenic isolates of the genus Fusarium were evaluated for their potential to produce cellulolytic and xylanolytic enzymes. The fungi were grown under solid-state conditions using a mixture of sugarcane bagasse and wheat bran as substrate with an initial moisture of 82%. Endoglucanases (ranging from 0.20 ± 0.03 to 5.31 ± 0.30 U/g of substrate), xylanases (ranging from 4.65 ± 0.76 to 125.57 ± 8.25 U/g of substrate), β-glucosidases (ranging from 21.48 ± 3.70 to 527.17 ± 22.14 U/g of substrate) and β-xylosidases (ranging from 5.61 ± 1.25 to 40.69 ± 1.26 U/g of substrate) were produced by all isolates. Enzymatic extracts from the best xylanase producers, F. lateritum var. majus and F. sacchari var. subglutinans , were tested for their capacities in promoting saccharification of delignified sugarcane bagasse. Amounts of 200.60 ± 10.60 mg/g and 280.00 ± 19.00 mg/g of reducing sugars, mainly xylose, were obtained after enzymatic hydrolysis by F. lateritum var. majus and F. sacchari var. subglutinans extracts, respectively. Up to now these species of Fusarium have been barely explored as sources of xylanolytic enzymes capable to degrade plant biomass, but our results open perspectives for their biotechnological use in the obtainment of xylose from delignified sugarcane bagasse. Graphical abstract fx1 Highlights • Screening of Fusarium sp. for xylan and cellulose hydrolyzing enzymes. • F. lateritum var. majus and F. sacchari var. subglutinans were the best xylanase producers. • The xylans from delignified sugarcane bagasse were efficiently hydrolysed. • Xylose was the main reducing sugar released from delignified sugarcane bagasse. [ABSTRACT FROM AUTHOR]

Teak plantations (Tectona grandis L. f.) in Ecuador are being affected by a complex disease of vascular wilt and dieback, with epidemic characteristics, without knowing the causal agent(s) so far. We proposed to describe the symptomatology of the disease and identify phytopathogenic fungi associated with diseased trees in the Ecuadorian Humid Tropic by morphophysiology. Three plantations of 2, 5 and 7 years of age were selected, in each three plots of 500 m2 were delimited. The symptomatologic description was made, evaluated the incidence and severity of the disease using a scale of five categories. By plot, three trees were dissected, whose tissues were taken to the laboratory, where three methodological strategies were used (wet chamber, carrot sandwiches, and potatodextrose-agar culture medium, PDA) to stimulate the expression of phytopathogens. In diseased trees, chlorosis, turgor loss, dry growth apices, emission of epicormic shoots in the stem, and fulminating wilt were detected. It was isolated and identified Ceratocystis fimbriata Ellis & Halst., and Fusarium species. consecutively with the three methodological strategies employed. The incidence of the disease was 16.6%, 15.2%, and 11.6% for plantations of 2, 5 and 7 years, respectively. The sick trees in the plantation of 2 years were found in scales 2, 4 and 5, while in plantations of 5 and 7 years they were located in scales 2, 3 and 5 of progress of the disease. [ABSTRACT FROM AUTHOR]

The main pathogens that affect the foliage and floral bracts of Heliconia cultivars in Las Heliconias National Park (Caicedonia, Colombia) were identified. Random samples were taken of foliage and floral bracts presenting symptoms of damage caused by phytopathogenic fungi. The degree of damage was described qualitatively and was correlated with the phytosanitary state of the crop. Reports of the evaluated plants indicated that 75% of the pathogens resided in the foliage and 25% resided in the floral bracts. The statistical analysis determined that the microorganisms Aspergillus sp., Fusarium sp., and Nigrospora sp. appeared equally in the two evaluated organs. The fungal genera found associated with plant sickness symptoms were considered to be phytopathogens. The degree of infection and development of disease varied from moderate lesions to severe infection. Reproductive fungi were present in the different plant organs studied and in organic matter residue in the soil. [ABSTRACT FROM AUTHOR]

Fusarium poae has been considered as a minor species among those that cause the FHB disease but in recent years several researchers have documented a high frequency of occurrence in several crops. We evaluated the ability of F. poae to produce symptoms in A. thaliana leaves. Moreover, we analyzed the defense of A. thaliana against F. poae using SA, JA, and ET mutants and we monitored the expression level of genes involved in the main signaling pathways related to plant defense. Symptoms were observed in the inoculated leaves demonstrating the ability of F. poae to infect A. thaliana leaves. Moreover, the npr1-1 mutants presented low symptoms compared to Col-0, etr2-1 , and coi1-1 and that the coi1-1 mutant was the most susceptible genotypes followed by etr2-1 genotypes. The RT-PCR revealed that PDF1.2 , CHI/PR3 , and ERF1 , three important JA-ET responsive genes and NPR1 and PR1 , which are regulated by SA signaling, were expressed upon F. poae inoculation. Our results suggest that JA and ET could play a key role in Arabidopsis leaves defense against F. poae representing the first evaluation of the response of the main A. thaliana phytohormones involved in plant defense in the presence of F. poae . [ABSTRACT FROM AUTHOR]

Potato crop is affected by numerous diseases in field, as well as in storage conditions, particularly in cold storage. Dry rot of potato is caused by Fusarium sp. Dry rot of seed tubers can reduce crop establishment by killing developing potato sprouts, and crop losses can be up to 25%, while more than 60% of tubers can be infected in storage. It is a rich source of energy, which supplement food source of a country. In this experiment, four systemic and four non-systemic fungicides were tested at different concentrations in vitro for their comparative efficacy against inhibition of the growth of Fusarium sp. through poisoned food technique. To manage these diseases effectively, different concentrations of fungicides were tested. Results revealed against Fusarium sp. that carbendazim and benomyl significantly inhibited the fungal growth even at its lower concentration (100 ppm) and proved statistically superior over the rest of the fungicides tested at different concentrations and among non-systemic fungicides, MEMC significantly inhibited the fungal growth even at its lower concentration (1000 ppm). [ABSTRACT FROM AUTHOR]

Scarcity of fresh water is a major environmental problem, and properly treated wastewater could be an alternative renewable water resource, especially for agriculture as the final point-of-use. But before wastewater can be reused, it must be treated to meet chemical and biological quality standards, which depend on the final use and legislation. Advanced Oxidation Processes (AOPs) have been demonstrated to be very efficient in decreasing the pathogen load in contaminated water. This study presents the experimental evaluation of several solar-driven AOPs, i.e., photo-Fenton (Fe 2+ , Fe 3+ ) at low reagent concentration, heterogeneous photocatalysis (TiO 2 ), and solar photoassisted H 2 O 2 treatment for removal of the spores of Fusarium sp., a worldwide phytopathogen. The experimental work was done in a pilot solar photoreactor with Compound Parabolic Collector (CPC). Disinfection of Fusarium solani spores by all treatments was excellent in distilled water, in simulated municipal wastewater effluent (SMWWE), and in real municipal wastewater effluents (RMWWE). Degradation of dissolved organic carbon (DOC) was also evaluated. The inactivation rates varied depending on the water matrix, and disinfection was fastest in distilled water followed by SMWWE, and RMWWE. The best F. solani inactivation rate was with photo-Fenton treatment (10/20 mg/L of Fe 2+ /H 2 O 2 ) at pH 3, followed by H 2 O 2 /Solar (10 mg/L) and finally TiO 2 /Solar was the slowest. These results underline the importance of solar AOPs and the CPC reactor technology as a good option for waterborne pathogen removal. [ABSTRACT FROM AUTHOR]