Search results for "Fungicide"
showing 10 items of 141 documents
Control of Fusarium graminearum in Wheat With Mustard-Based Botanicals: From in vitro to in planta
2020
Fusarium graminearum is a phytopathogenic fungus that causes Fusarium head blight in small-grain cereals, such as wheat, with significant yield reductions. Moreover, it contaminates the cereal grains with health-threatening mycotoxins, such as deoxynivalenol (DON), jeopardizing food and feed safety. Plant-based biopesticides, i.e. botanicals, have recently gained increased interest in crop protection as alternatives to synthetic chemical products. The main objective of this study was to test the control efficacy of botanicals based on white or Indian/Oriental mustard seed flours (Tillecur – Ti, Pure Yellow Mustard – PYM, Pure Oriental Mustard – POM, Oriental Mustard Bran – OMB) on F. gramin…
Flow cytometric assay for estimating fungicidal activity of Amphotericin B in human serum
1992
We describe a simple and rapid bioassay for estimating fungicidal activity of Amphotericin B in human serum using flow cytometry. The method exploits the fact that Candida albicans damaged by Amphotericin B show a decrease in size and take up propidium iodide to exhibit a red fluorescence after deoxycholate treatment. These phenomena display characteristic dose dependencies, and their assessment permits serum fungicidal activity to be broadly grouped into three categories: (1) subfungicidal; (2) fungicidal; and (3) strongly fungicidal. In normal human serum, these three categories correspond to Amphotericin B concentrations of 0 less than or equal to 0.5 micrograms/ml, 0.75-1.5 micrograms/m…
Inhibition of Mycotoxigenic Fungi in Different Vegetable Matrices by Extracts of Trichoderma Species
2021
Post-harvest fungal diseases of plant products are a serious concern leading to economic losses and health risks. Moreover, the use of synthetic chemical fungicides to prevent these diseases is limited due to toxic residues. This study aimed at determining the effective dose of extracts of Trichoderma 
Potential of Antifungal Proteins (AFPs) to Control Penicillium Postharvest Fruit Decay
2021
Penicillium phytopathogenic species provoke severe postharvest disease and economic losses. Penicillium expansum is the main pome fruit phytopathogen while Penicillium digitatum and Penicillium italicum cause citrus green and blue mold, respectively. Control strategies rely on the use of synthetic fungicides, but the appearance of resistant strains and safety concerns have led to the search for new antifungals. Here, the potential application of different antifungal proteins (AFPs) including the three Penicillium chrysogenum proteins (PAF, PAFB and PAFC), as well as the Neosartorya fischeri NFAP2 protein to control Penicillium decay, has been evaluated. PAFB was the most potent AFP against …
Chitin Deacetylase, a Novel Target for the Design of Agricultural Fungicides
2021
Fungicide resistance is a serious problem for agriculture. This is particularly apparent in the case of powdery mildew fungi. Therefore, there is an urgent need to develop new agrochemicals. Chitin is a well-known elicitor of plant immunity, and fungal pathogens have evolved strategies to overcome its detection. Among these strategies, chitin deacetylase (CDA) is responsible for modifying immunogenic chitooligomers and hydrolysing the acetamido group in the N-acetylglucosamine units to avoid recognition. In this work, we tested the hypothesis that CDA can be an appropriate target for antifungals using the cucurbit powdery mildew pathogen Podosphaera xanthii. According to our hypothesis, RNA…
The Effect of Pesticides on the Tomato Bacterial Speck Disease Pathogen Pseudomonas Syringae pv. Tomato
2020
A significant part of the used pesticides does not reach the target organisms and, while remaining in the agrophytocenosis, influences all living organisms in it. Having a toxic and often mutagenic effect, pesticides induce morphological and physiological changes in the cells of microorganisms and are the cause of phenotypic heterogeneity of their populations. However, the effect of pesticides on phytopathogenic bacteria as non-target microorganisms remains out of the field of view for most researchers. However, the use of pesticides can lead to expansion of the diversity of existing phytopathogens and, as a consequence, complications of identification of the pathogens, loss of resistance b…
Design and development of heterologous competitive immunoassays for the determination of boscalid residues
2014
Boscalid is a modern agrochemical belonging to the so-called chemical class of succinate dehydrogenase inhibitor fungicides. With the aim of developing rapid analytical screening methods for this relevant compound, we herein report the synthesis of new boscalid mimics and the study of their suitability for the production of polyclonal antibodies. Aliphatic spacer arms equivalent in length and composition were tethered at two different aromatic rings of the target molecular structure. These haptens, besides being used for immunization, were employed in the development of heterologous competitive enzyme-linked immunosorbent assays (cELISAs) in order to improve assay detectability. Direct and …
Total Synthesis of the Antifungal Natural Product Mollisin
2013
Mollisin, a bioactive polyketide secondary metabolite of the fungus Mollisia caesia, was synthesized in nine linear steps from commercially available 2,6-dimethyl-γ-pyrone. A key transformation in this first total synthesis of mollisin was the ipso substitution of an arylstannane, which permitted the otherwise cumbersome introduction of the characteristic dichloroacetyl moiety. The fungal fungicide was obtained in an overall yield of 9 %.
Highly sensitive monoclonal antibody-based immunoassays for boscalid analysis in strawberries
2018
Boscalid is an agrochemical recently developed for crop protection and the most significant member of the succinate dehydrogenase inhibitor group of fungicides. In this study, a collection of high-affinity monoclonal antibodies was generated to boscalid. By using a series of haptens with a linker at alternative tethering sites of the boscalid framework, specific antibodies were isolated as well as antibodies that also recognized the main boscalid metabolite. Two immunoassays were developed using different ELISA formats. Optimized assays displayed very high sensitivities (limits of detection were near 0.01 µg/L). Trueness and precision for the determination of the target analyte in strawberr…
Antifungal Activity of Biocontrol Agents In Vitro and Potential Application to Reduce Mycotoxins (Aflatoxin B1 and Ochratoxin A)
2021
Food bio-preservatives are requested as substituents of chemical pesticides in food. The aim of this study was to carry out a screening of twenty biocontrol agents (BCAs) for their potential fungicidal activity in vitro. Twenty BCAs were tested against ten pathogenic fungi. Some of the cell-free supernatants (CFS) tested showed in vitro antifungal activity versus pathogenic fungi. The highest fungicidal activity was observed in the fermented CFS of Paenibacillus chibensis CECT 375, Bacillus amyloliquefaciens CECT 493, and Pantoea agglomerans CECT 850, which showed a minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) values of 125 and 250 g/L, respectively. The…