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1.
Sci Total Environ ; 948: 174578, 2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38981541

RESUMO

Pesticide active ingredients are frequently detected in the rivers, creeks, wetlands, estuaries, and marine waters of the Great Barrier Reef (GBR) region and are one of the main contributors to poor water quality. Pesticide concentrations detected in the environment through water quality monitoring programs can be compared against estimates of ecologically "safe" concentrations (i.e., water quality guidelines) to assess the potential hazard and risk posed to aquatic ecosystems. Water quality guidelines are also required to estimate the aquatic risk posed by pesticide mixtures, which is used for the Reef 2050 Water Quality Improvement Plan pesticide target. Seventy-four pesticide active ingredients and their degradates are frequently detected in GBR catchment waterways, however many do not have water quality guidelines in the Australian and New Zealand Guidelines for Fresh and Marine Water Quality. The current study derives ecotoxicity threshold values (ETVs) as unendorsed guideline values for active ingredients in two fungicides (4-hydroxychlorothalonil (fungicide degradate) and carbendazim) and two insecticides (dimethoate and methoxyfenozide) that are commonly detected in GBR catchment waterways. The proposed ETVs have been derived using species sensitivity distributions, as recommended in the Australian and New Zealand nationally endorsed method for deriving water quality guidelines for aquatic ecosystem protection. Four ETVs were derived for each chemical with values that should theoretically protect 99, 95, 90 and 80 % of species (i.e., PC99, PC95, PC90, PC80, respectively). The PC99 and PC95 values for 4-hydroxychlorothalonil, carbendazim, dimethoate and methoxyfenozide were 0.49 µg/L and 4 µg/L, 0.029 µg/L and 0.45 µg/L, 0.11 µg/L and 5.8 µg/L and 0.19 µg/L and 2 µg/L, respectively. The ETVs will be used in an ecological hazard and risk assessment across GBR waterways in part two of this study. The ETVs can also be used to assess potential risk across Australia and internationally where monitoring data are available.

2.
Heliyon ; 10(12): e32564, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38952372

RESUMO

The present study was carried out at the Plant Pathology Hafizabad Research Station, the University of Layyah, during the crop seasons 2021-2022 and 2022-2023 to evaluate the response of various wheat genotypes against leaf rust severity (%), environmental conditions favourable for disease development and grain yield. Except for minimum temperature and minimum relative humidity, which had a negative association with disease development, there was a significant correlation between leaf rust severity (%) and all environmental conditions such as maximum temperature, maximum relative humidity, rainfall, and wind speed. All epidemiological variables such as maximum temperature, minimum temperature, minimum relative humidity, rainfall and wind speed significantly affect the disease progression. The disease predictive model accounted for 48-69 % variability in leaf rust severity. The model performance was evaluated using the coefficient of determination (R2 = 0.69) and RMSE, both demonstrated acceptable predictive results for leaf rust severity (%) management. Leaf rust severity (%) increased with an increase in maximum temperature (17.8-30 °C), maximum relative humidity (76.3-85 %), rainfall (2.2-10.85 mm) and wind speed 1.1-2.7 km/h and decreased with the increase of minimum temperature (7.91-16.71 °C) minimum relative humidity (47.15-56.45 %) during both rating seasons 2021-2022 and 2022-2023. The single and two applications of fungicides at the Zadok's scale 3, ZS 4.3, and ZS 5.4 stages led to a significant reduction in grain yield losses caused by leaf rust severity (%) in both the 2021-2022 and 2022-2023 crop seasons. Single and two sprays of prothioconazole, were found to be the first choice among all treatments to reduce the disease severity and increase grain production and maximum gross revenue (513.1-777.8$/ha), as compared to followed by single and two sprays of propiconazole (Progress), tebuconazole + trifloxystrobin, tebuconazole, bixafen + tebuconazole, and propiconazole (Tilt), respectively. These findings recommend the involvement of genotype resistance and weather predictors in wheat leaf rust development, along with fungicide application studies, to improve the predictability of host resistance to disease, future models, and the sustainability of disease control methods.

3.
Environ Pollut ; 358: 124490, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960114

RESUMO

Pyraclostrobin, a typical representative of strobilurin fungicides, is extensively used in agriculture to control fungi and is often detected in water bodies and food. However, the comprehensive toxicological molecular mechanism of pyraclostrobin requires further study. To assess the toxic effects and underlying mechanisms of pyraclostrobin on aquatic organisms, zebrafish embryos were exposed to pyraclostrobin (20, 40, and 60 µg/L) until 96 h post fertilization (hpf). These results indicated that exposure to pyraclostrobin induces morphological alterations, including spinal curvature, shortened body length, and smaller eyes. Furthermore, heart developmental malformations, such as pericardial edema and bradycardia, were observed. This indicated severe cardiotoxicity induced by pyraclostrobin in zebrafish embryos, which was confirmed by the dysregulation of genes related to heart development. Besides, our findings also demonstrated that pyraclostrobin enhanced the contents of reactive oxygen species (ROS) and malondialdehyde (MDA), up-regulated catalase (CAT) activity, but inhibited superoxide dismutase (SOD) activity. Subsequently, the NF-κb signaling pathway was further studied, and the results indicated that the up-regulation of tnf-α, tlr-4, and myd88 activated the NF-κb signaling pathway and up-regulated the relative expression level of pro-inflammatory cytokines, such as cc-chemokine, ifn-γ, and cxcl-clc. Collectively, this study revealed that pyraclostrobin exposure induces developmental toxicity and cardiotoxicity, which may result from a combination of oxidative stress and inflammatory responses. These findings provide a basis for continued evaluation of the effects and ecological risks of pyraclostrobin on the early development of aquatic organisms.

4.
Pest Manag Sci ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39032014

RESUMO

BACKGROUND: Utilizing fungicides to protect crops from diseases is an effective method, and novel eco-friendly plant-derived fungicides with high efficiency and low toxicity are urgent requirements for sustainable crop protection. RESULT: Two series of rosin-based fungicides (totally 35) were designed and synthesized. In vitro fungicidal activity revealed that Compound 6a (Co. 6a) effectively inhibited the growth of Valsa mali [median effective concentration (EC50) = 0.627 µg mL-1], and in vivo fungicidal activity suggested a significant protective efficacy of Co. 6a in protecting both apple branches (35.12% to 75.20%) and apples (75.86% to 90.82%). Quantum chemical calculations (via density functional theory) results indicated that the primary active site of Co. 6a lies in its amide structure. Mycelial morphology and physiology were investigated to elucidate the mode-of-action of Co. 6a, and suggested that Co. 6a produced significant cell membrane damage, accelerated electrolyte leakage, decreased succinate dehydrogenase (SDH) protein activity, and impaired physiological and biochemical functions, culminating in mycelial mortality. Molecular docking analysis revealed a robust binding energy (ΔE = -7.29 kcal mol-1) between Co. 6a and SDH. Subsequently, biosafety evaluations confirmed the environmentally-friendly nature of Co. 6a via the zebrafish model, yet toxicological results indicated that Co. 6a at median lethal concentration [LC50(96)] damaged the gills, liver and intestines of zebrafish. CONCLUSION: The above research offers a theoretical foundation for exploiting eco-friendly rosin-based fungicidal candidates in sustainable crop protection. © 2024 Society of Chemical Industry.

5.
Plant Dis ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030659

RESUMO

Pecan is a valuable nut crop cultivated in the southeastern US. Among the major yield-limiting factors in the region is scab, caused by the plant pathogenic fungus Venturia effusa. Managing scab in tall trees (15 to 25+ m) in pecan orchards is challenging due to the limitations of getting sufficient spray coverage throughout the canopy. We explored the effects of hedge-pruning on scab in three orchards: 14 m tall cv. Desirable trees winter hedge-pruned on alternate sides to 11 m (site 1), 18 m tall cv. Stuart trees hedge-pruned on both sides simultaneously to 11 m (site 2), and 15 m tall cv. Caddo trees winter hedge-pruned in winter vs. summer to 11 m (site 3). At site 1 and 2 hedge-pruned trees were compared to non-pruned control trees. All trees received recommended fungicide applications to control scab via air-blast sprayer. Disease incidence and/or severity was assessed at different sample heights on shoots, foliage and fruit during three seasons (2020, 2021, and 2022). At site 1 the hedge pruned trees often had significantly or numerically more severe scab on foliage and fruit compared to the control trees, although the differences were mostly small. The frequency of mature fruit with scab severity <10% was greatest on control trees in 2021 and 2022. At site 2, there were few differences between hedge-pruned and control trees (on fruit, scab severity was either significantly less on hedge-pruned trees, or not different to the control), but the frequency of mature fruit with scab severity <10% was consistently greatest on hedge-pruned trees. At site 3, scab intensity was low, and there were no significant differences in scab severity between winter- and summer-pruning treatments. At sites 1 and 2 there was generally more severe scab at greater sample heights compared to low in the canopy. At site 3 there was little effect of height on disease. The benefit of hedge-pruning likely increases with tree height in scab-susceptible cultivars. If a tree is >~15 m tall, a greater proportion of the fruit will be within reach of efficacious spray coverage from air-blast sprayers.

6.
Plants (Basel) ; 13(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38999697

RESUMO

Sorghum northern anthracnose is a leaf disease affecting sorghum, which results in plant death and substantial yield loss. This study aimed to effectively understand the disease, clarify its biological characteristics, and evaluate the resistance of germplasm resources. A field sample was collected to isolate and purify the pathogen. The pathogen, identified as Kabatiella zeae Narita et Hiratsuka using both morphological and molecular techniques, was further confirmed as the causative agent of northern anthracnose of sorghum following Robert Koch's principles. The results revealed the optimal culture temperature to be 25 °C, preferred dark culture conditions, and the best growth on potato glucose agar medium with sucrose and L-leucine as the optimal carbon and nitrogen sources, respectively. A total of 138 sorghum germplasm resources were inoculated and evaluated using the isolated pathogen, with 20 lines (14.49%) exhibiting high resistance, 18 lines (13.04%) showing disease resistance, 27 lines (19.57%) demonstrating medium resistance, 37 lines (26.81%) being susceptible, and 36 lines (26.09%) classified as highly susceptible. The indoor fungicide screening was conducted through pathogen medium application, and enilconazole, pyraclostrobin, methylthiophanate, and flusilazole were screened for the best fungicide inhibition with a 100% inhibition rate compared with the control. This study provides reference for field pharmaceutical control in sorghum production.

7.
J Agric Food Chem ; 72(26): 14535-14546, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38906830

RESUMO

The development of new fungicide molecules is a crucial task for agricultural chemists to enhance the effectiveness of fungicides in agricultural production. In this study, a series of novel fluoroalkenyl modified succinate dehydrogenase inhibitors were synthesized and evaluated for their antifungal activities against eight fungi. The results from the in vitro antifungal assay demonstrated that compound 34 exhibited superior activity against Rhizoctonia solani with an EC50 value of 0.04 µM, outperforming commercial fluxapyroxad (EC50 = 0.18 µM) and boscalid (EC50 = 3.07 µM). Furthermore, compound 34 showed similar effects to fluxapyroxad on other pathogenic fungi such as Sclerotinia sclerotiorum (EC50 = 1.13 µM), Monilinia fructicola (EC50 = 1.61 µM), Botrytis cinerea (EC50 = 1.21 µM), and also demonstrated protective and curative efficacies in vivo on rapeseed leaves and tomato fruits. Enzyme activity experiments and protein-ligand interaction analysis by surface plasmon resonance revealed that compound 34 had a stronger inhibitory effect on succinate dehydrogenase compared to fluxapyroxad. Additionally, molecular docking and DFT calculation confirmed that the fluoroalkenyl unit in compound 34 could enhance its binding capacity with the target protein through p-π conjugation and hydrogen bond interactions.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos , Proteínas Fúngicas , Fungicidas Industriais , Rhizoctonia , Succinato Desidrogenase , Succinato Desidrogenase/antagonistas & inibidores , Succinato Desidrogenase/química , Succinato Desidrogenase/metabolismo , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Fungicidas Industriais/síntese química , Rhizoctonia/efeitos dos fármacos , Rhizoctonia/enzimologia , Relação Estrutura-Atividade , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Doenças das Plantas/microbiologia , Simulação de Acoplamento Molecular , Botrytis/efeitos dos fármacos , Botrytis/enzimologia , Ascomicetos/efeitos dos fármacos , Ascomicetos/enzimologia , Solanum lycopersicum/microbiologia , Solanum lycopersicum/química , Estrutura Molecular
8.
Pest Manag Sci ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38843449

RESUMO

BACKGROUND: Fusarium head blight (FHB) caused by Fusarium graminearum species complex (FGSG) remains a major challenge to cereal crops and resistance to key fungicides by the pathogen threatens control efficacy. Pydiflumetofen, a succinate dehydrogenase inhibitor, and phenamacril, a cyanoacrylate fungicide targeting myosin I, have been applied to combat this disease. Nonetheless, emergence of pydiflumetofen resistance in a subset of field isolates alongside laboratory-induced facile generation of phenamacril-resistant isolates signals a critical danger of resistance proliferation. RESULTS: Our study investigates the development of dual resistance to these fungicides in F. graminearum. Utilizing pydiflumetofen-resistant (PyR) and -sensitive (PyS) isolates, we obtained dual-resistant (PyRPhR) and phenamacril-resistant (PySPhR) mutants on potato sucrose agar containing phenamacril. Mutation rates for phenamacril resistance were comparable between pydiflumetofen-resistant and -sensitive isolates, implying independent pathways for resistance development. The mutants compromised in fungal growth, competitive viability and deoxynivalenol production, suggesting fitness penalties for the dual-resistant mutants. However, no cross-resistance was found with tebuconazole or fludioxonil. In addition, we characterized four critical amino acid changes (S217L, C423R, K537T, E420G) in the Myo1 that were verified to confer phenamacril resistance in F. graminearum. CONCLUSION: This research indicates the possibility of resistance development for both pydiflumetofen and phenamacril in F. graminearum and emphasizes the need for fungicide resistance management for FHB. © 2024 Society of Chemical Industry.

9.
Toxicol Res (Camb) ; 13(3): tfae087, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38845614

RESUMO

Zebrafish being the best animal model to study, every attempt has been made to decipher the toxic mechanism of every fungicide of usage and interest. It is important to understand the multiple targets of a toxicant to estimate the toxic potential in its totality. A total of 22 fungicides of different classes like amisulbrom, azoxystrobin, carbendazim, carboxin, chlorothalonil, difenoconazole, etridiazole, flusilazole, fluxapyroxad, hexaconazole, kresoxim methyl, mancozeb, myclobutanil, prochloraz, propiconazole, propineb, pyraclostrobin, tebuconazole, thiophanate-methyl, thiram, trifloxystrobin and ziram were reviewed and analyzed for their multiple explored targets in zebrafish. Toxic end points in zebrafish are highly informative when it comes to network analysis. They provide a window into the molecular and cellular pathways that are affected by a certain toxin. This can then be used to gain insights into the underlying mechanisms of toxicity and to draw conclusions on the potential of a particular compound to induce toxicity. This knowledge can then be used to inform decisions about drug development, environmental regulation, and other areas of research. In addition, the use of zebrafish toxic end points can also be used to better understand the effects of environmental pollutants on ecosystems. By understanding the pathways affected by a given toxin, researchers can determine how pollutants may interact with the environment and how this could lead to health or environmental impacts.

10.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928507

RESUMO

The necrotrophic plant pathogenic fungus Botrytis cinerea (Pers., 1794), the causative agent of gray mold disease, causes significant losses in agricultural production. Control of this fungal pathogen is quite difficult due to its wide host range and environmental persistence. Currently, the management of the disease is still mainly based on chemicals, which can have harmful effects not only on the environment and on human health but also because they favor the development of strains resistant to fungicides. The flexibility and plasticity of B. cinerea in challenging plant defense mechanisms and its ability to evolve strategies to escape chemicals require the development of new control strategies for successful disease management. In this review, some aspects of the host-pathogen interactions from which novel and sustainable control strategies could be developed (e.g., signaling pathways, molecules involved in plant immune mechanisms, hormones, post-transcriptional gene silencing) were analyzed. New biotechnological tools based on the use of RNA interference (RNAi) are emerging in the crop protection scenario as versatile, sustainable, effective, and environmentally friendly alternatives to the use of chemicals. RNAi-based fungicides are expected to be approved soon, although they will face several challenges before reaching the market.


Assuntos
Botrytis , Interações Hospedeiro-Patógeno , Doenças das Plantas , Interferência de RNA , Botrytis/patogenicidade , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Interações Hospedeiro-Patógeno/genética , Fungicidas Industriais/farmacologia
11.
Front Plant Sci ; 15: 1411625, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38938640

RESUMO

As an evergreen shrub, Euonymus japonicus plays a crucial role in urban landscape construction, and its growth is affected by severe foliar anthracnose caused by Colletotrichum spp. However, the biodiversity of Colletotrichum species associated with anthracnose on E. japonicus remains undetermined. This study involved a two-year collection of E. japonicus leaf samples with typical anthracnose symptoms from 9 districts in Beijing, China. A total of 194 Colletotrichum isolates were obtained, and eight Colletotrichum species were subsequently identified using morphological characteristics and molecular identification with the ACT, GADPH, CHS, TUB2, and CAL genes, as well as the rDNA-ITS region. These species included Colletotrichum aenigma, C. fructicola, C. gloeosporioides, C. grossum, C. hebeiense, C. karstii, C. siamense, and C. theobromicola with C. siamense being the most prevalent (57%), followed by C. aenigma and C. theobromicola. Furthermore, C. fructicola, C. grossum and C. hebeiense are reported for the first time as causal agents of anthracnose on E. japonicus worldwide, and C. karstii is newly reported to be associated with E. japonicus anthracnose in China. Pathogenicity tests revealed that all tested isolates exhibited pathogenicity in the presence of wounds, emphasizing the need to avoid artificial or mechanical wounds to prevent infection in E. japonicus management. The EC50 values of five fungicides, namely difenoconazole, flusilazole, tebuconazole, hexaconazole, and prochloraz, were found to be less than 10 mg/L, indicating their strong potential for application. Notably, the EC50 of prochloraz was less than 0.05 mg/L for C. theobromicola. These findings offer valuable insights for the management of anthracnose on E. japonicus.

12.
Pestic Biochem Physiol ; 202: 105954, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38879337

RESUMO

Fungicides are often used prophylactically, to control fungal diseases. Although fungicides have been designed to control pests/fungi, they frequently share molecular targets with non-target species, including humans. Tebuconazole, a fungicide belonging to the class of triazoles, is widely employed, has moderate to high persistence in soil, and can be found in different environmental levels. This fungicide is metabolized to the main hydroxy-derived metabolite, Tebuconazole-tert-butyl-hydroxy (or hydroxytebuconazole). This study aims to unveil the action mechanism of Tebuconazole and the role played by its metabolite, Tebuconazole-tert-butyl-hydroxy (5-(4-Chlorophenyl)-2,2-dimethyl-3-(1H-1,2,4-triazol-1-ylmethyl)-1,3-pentanediol), within the expected spectrum of toxicity. In silico and in vitro analyses (MTT assay, cell cycle evaluation, annexin/PI assay, ROS accumulation assay, and mitochondrial membrane potential determination) were performed in HepG2 cells for 24 h and 48 h. Although in silico analysis suggested that both Tebuconazole and Tebuconazole-tert-butyl-hydroxy are potentially hepatotoxic, only Tebuconazole affected the tested cell line. Reduced MTT metabolism, and decreased mitochondrial membrane potential were the main findings. In conclusion, the action mechanism of Tebuconazole may be related to mitochondrial dysfunction. However, the findings of this study pointed out that Tebuconazole-tert-butyl-hydroxy does not play an important role in Tebuconazol toxicity. The study has generated new data that will help to understand how fungicides behave in the environment.


Assuntos
Fungicidas Industriais , Potencial da Membrana Mitocondrial , Triazóis , Triazóis/toxicidade , Humanos , Fungicidas Industriais/toxicidade , Células Hep G2 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos
13.
Food Chem ; 457: 140116, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38924914

RESUMO

For the first time, a magnetic carbon nanocomposite was synthesized using one-step hydrothermal procedure, employing bovine serum albumin, curcumin, and ferric ammonium citrate. Additionally, the application of this novel composite as an adsorbent for magnetic dispersive solid phase extraction of fungicides and pesticides from water and food samples is a unique aspect of this study. Under optimum conditions (salt concentration: 5.0% w/v, pH: 7.0, desorption solvent: ethanol, sorbent amount: 20 mg, extraction time: 20 min, desorption time: 3 min, stirring rate: 500 rpm, sample volume: 30 mL, extraction temperature: room temperature, and desorption solvent volume: 150 µL) linearity (2.5 to 1400 ng mL-1), coefficients of determination (R2 ≥ 0.997), limits of detection (0.75 to 1.5 ng mL-1), and limits of quantification (2.5 to 5.0 ng mL-1) were achieved. The method validation results showed extraction recovery ranging from 71.2% to 93.4%, and preconcentration factors ranging from 142.5 to 186.1.

14.
J Agric Food Chem ; 72(23): 13154-13163, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38780776

RESUMO

Finding safe and environmentally friendly fungicides is one of the important strategies in modern pesticide research and development. In this work, the antipathogenic effects of the fungus Trichaptum laricinum against the anthracnose pathogen Colletotrichum anthrisci were studied. The EtOAc extract of T. laricinum showed remarkable antifungal activity against C. anthrisci with an inhibition rate of 50% at 256 µg/mL. Bioguided isolation of the cultural broth of T. laricinum produced four new drimane sesquiterpenes, trichalarins A-D (1-4), and six other metabolites (5-10). Their structures were established by extensive spectroscopic methods, quantum chemical calculations, and single-crystal X-ray diffraction. All compounds exhibited antifungal activity against C. anthrisci with minimum inhibitory concentrations (MICs) of 8-64 µg/mL in vitro. Further in vivo assay suggested that compounds 2, 6, and 9 could significantly inhibit C. anthrisci growth in avocado fruit with inhibition rates close to 80% at the concentration of 256 µg/mL, while compounds 2 and 6 had an inhibition rate over 90% at the concentration of 512 µg/mL. The EtOAc extract of T. laricinum had no inhibitory effect on Pinus massoniana seed germination and growth at the concentration of 2 mg/mL, showing good environmental friendliness. Thus, the fungus T. laricinum could be considered as an ideal biocontrol strain, and its metabolites provided a diverse material basis for the antibiotic agents.


Assuntos
Colletotrichum , Fungicidas Industriais , Testes de Sensibilidade Microbiana , Doenças das Plantas , Colletotrichum/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Fungicidas Industriais/química , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Estrutura Molecular , Sesquiterpenos/farmacologia , Sesquiterpenos/química
15.
Sci Total Environ ; 937: 173539, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-38806130

RESUMO

The occurrence and ecological impacts of emerging fungicides in the environment has gained increasing attention. This study applied an in-jar passive sampling device based on silicone rubber (SR) film to measuring the freely dissolved concentration (Cfree) of 6 current-use fungicides as a critical index of bioavailability in water and soils. The kinetics parameters including SR-water, soil-water, and organic carbon-water partition coefficients and sampling rates of the target fungicides were first attained and characterized well with their physicochemical properties. The in situ and ex situ field deployment in Hefei City provided the assessment of contaminated levels for these fungicides in rivers and soils. The Cfree of triadimefon and azoxystrobin was estimated at 0.54 ± 0.07-17.4 ± 2.5 ng L-1 in Nanfei River and Chao Lake, while triadimefon was only found in Dongpu Reservoir water with Cfree below 0.66 ± 0.04 ng L-1. The results exhibited that the equilibrium duration of 7 d was suitable for water application but a longer interval of 14 d was recommended for soil sampling. This work demonstrated the advantages of the proposed strategy in terms of fast monitoring within 2 weeks and high sensitivity down to detection limits in 0.5-5 ng L-1. The in-jar passive sampling device can be extrapolated to the evaluation for a wide coverage of organic pollutants in water and soils.


Assuntos
Monitoramento Ambiental , Fungicidas Industriais , Elastômeros de Silicone , Poluentes do Solo , Solo , Poluentes Químicos da Água , Fungicidas Industriais/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Poluentes do Solo/análise , Solo/química , China , Rios/química
16.
J Biotechnol ; 388: 72-82, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38616039

RESUMO

The 2-pyrone moiety is present in a wide range of structurally diverse natural products with various biological activities. The plant biosynthetic routes towards these compounds mainly depend on the activity of either type III polyketide synthase-like 2-pyrone synthases or hydroxylating 2-oxoglutarate dependent dioxygenases. In the present study, the substrate specificity of these enzymes is investigated by a systematic screening using both natural and artificial substrates with the aims of efficiently forming (new) products and understanding the underlying catalytic mechanisms. In this framework, we focused on the in vitro functional characterization of a 2-pyrone synthase Gh2PS2 from Gerbera x hybrida and two dioxygenases AtF6'H1 and AtF6'H2 from Arabidopsis thaliana using a set of twenty aromatic and aliphatic CoA esters as substrates. UHPLC-ESI-HRMSn based analyses of reaction intermediates and products revealed a broad substrate specificity of the enzymes, enabling the facile "green" synthesis of this important class of natural products and derivatives in a one-step/one-pot reaction in aqueous environment without the need for halogenated or metal reagents and protective groups. Using protein modeling and substrate docking we identified amino acid residues that seem to be important for the observed product scope.


Assuntos
Arabidopsis , Coenzima A , Ésteres , Pironas , Pironas/metabolismo , Pironas/química , Ésteres/química , Ésteres/metabolismo , Arabidopsis/enzimologia , Especificidade por Substrato , Coenzima A/metabolismo , Coenzima A/química , Simulação de Acoplamento Molecular , Produtos Biológicos/metabolismo , Produtos Biológicos/química , Dioxigenases/metabolismo , Dioxigenases/química
17.
Phytopathology ; 114(5): 843-854, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648074

RESUMO

Climate change is having a significant impact on global agriculture, particularly on vegetable crops, which play a critical role in global nutrition. Recently, increasing research has concentrated on the impact of climate change on vegetable crop diseases, with several studies being conducted in phytotrons, which have been used to explore the effects of increased temperatures and CO2 concentrations to simulate future scenarios. This review focuses on the combined effects of temperature and carbon dioxide increases on foliar and soilborne vegetable diseases, as evaluated under phytotron conditions. The influence of climate change on mycotoxin production and disease management strategies is also explored through case studies. The results offer valuable information that can be used to guide both seed and agrochemical industries, as well as to develop disease-resistant varieties and innovative control measures, including biocontrol agents, considering the diseases that are likely to become prevalent under future climatic scenarios. Recommendations on how to manage vegetable diseases under ongoing climate change are proposed to facilitate plants' adaptation to and enhanced against the changing conditions. A proactive and comprehensive response to climate-induced challenges in vegetable farming is imperative to ensure food security and sustainability.


Assuntos
Agricultura , Mudança Climática , Produtos Agrícolas , Doenças das Plantas , Verduras , Doenças das Plantas/prevenção & controle , Produtos Agrícolas/crescimento & desenvolvimento , Dióxido de Carbono/análise , Temperatura , Micotoxinas/análise
18.
Talanta ; 274: 126038, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579419

RESUMO

Herein, a High-Throughput Semi-automated Emulsive Liquid-Liquid Microextraction (HTSA-ELLME) method was developed to detect Succinate Dehydrogenase Inhibitor (SDHI) fungicides in food samples via UHPLC-MS/MS. The Oil-in-Water (O/W) emulsion comprising a hydrophobic extractant and water was dilutable with the aqueous sample solution. Upon injecting the primary emulsion into the sample solution, a secondary O/W emulsion was formed, allowing SDHI fungicides to be extracted. Subsequently, a NaCl-saturated solution was injected in the secondary O/W emulsion as a demulsifier to rapidly separate the extractant, eliminating the need for centrifugation. A 12-channel electronic micropipette was used to achieve a high-throughput semi-automation of the novel sample pretreatment. The linear range was 0.003-0.3 µg L-1 with R2 > 0.998. The limit of detection was 0.001 µg L-1. The HTSA-ELLME method successfully detected SDHI fungicides in water, juice, and alcoholic beverage samples, with recoveries and relative standard deviations of 82.6-106.9% and 0.8-5.8%, respectively. Unlike previously reported liquid-liquid microextraction approaches, the HTSA-ELLME method is the first to be both high-throughput and semi-automated and may aid in designing pesticide pretreatment processes in food samples.


Assuntos
Bebidas Alcoólicas , Sucos de Frutas e Vegetais , Fungicidas Industriais , Microextração em Fase Líquida , Espectrometria de Massas em Tandem , Microextração em Fase Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Fungicidas Industriais/análise , Sucos de Frutas e Vegetais/análise , Bebidas Alcoólicas/análise , Emulsões/química , Água/química , Contaminação de Alimentos/análise , Automação
19.
J Fungi (Basel) ; 10(4)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38667926

RESUMO

Alternaria leaf blight has recently been described as an emerging fungal disease of apple trees which is causing the significant damage in the apple-growing areas of Tianshui and Jingning, Gansu, China. In the present study, the pathogen species involved in apple leaf blight and its biological characteristics were identified, and the inhibitory activity of different botanical fungicides against the pathogen was evaluated in vitro. Four strains were isolated from the symptomatic areas of necrotic apple leaves, and initially healthy leaves showed similar symptoms to those observed in orchards after inoculation with the ABL2 isolate. The ABL2 isolate was identified as Alternaria tenuissima based on the morphological characteristics of its colonies, conidiophores, and conidia, and this was also confirmed by multi-gene sequence (ITS, OPA10-2, Alta-1, and endoPG) analysis and phylogenic analysis. The optimum temperature, pH, carbon source, and nitrogen source for the growth of A. tenuissima mycelia were 28 °C, 6-7, soluble starch, and soy flour, respectively. In addition, the botanical fungicide eugenol exhibited the highest inhibitory effect on the mycelial growth and conidia germination of A. tenuissima, and the median effective concentration (EC50) values were 0.826 and 0.755 µg/mL, respectively. The protective and curative efficacy of eugenol were 86.85% and 76.94% after inoculation in detached apple leaves at a concentration of 4 µg/mL. Our research provides new insights into the control of apple leaf blight disease by applying botanical fungicides.

20.
J Food Sci ; 89(5): 2943-2955, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38557930

RESUMO

Bell pepper presents rapid weight loss and is highly susceptible to gray mold caused by the fungus Botrytis cinerea. The most employed method to control this disease is the application of synthetic fungicides such as thiabendazole (TBZ); however, its continued use causes resistance in fungi as well as environmental problems. For these reasons, natural alternatives arise as a more striking option. Currently, bell pepper fruits are coated with carnauba wax (CW) to prevent weight loss and improve appearance. Moreover, CW can be used as a carrier to incorporate essential oils, and previous studies have shown that thyme essential oil (TEO) is highly effective against B. cinerea. Therefore, this study aimed to evaluate the effect of CW combined with TEO on the development of gray mold and maintenance of microestructural and postharvest quality in bell pepper stored at 13°C. The minimal inhibitory concentration of TEO was 0.5%. TEO and TBZ provoked the leakage of intracellular components. TEO and CW + TEO treatments were equally effective to inhibit the development of gray mold. On the quality parameters, firmness and weight loss were ameliorated with CW and CW + TEO treatments; whereas lightness increased in these treatments. The structural analysis showed that CW + TEO treatment maintained the cell structure reducing the apparition of deformities. The results suggest that CW + TEO treatment could be used as a natural and effective antifungal retarding the appearance of gray mold and maintaining the postharvest quality of bell pepper. PRACTICAL APPLICATION: CW and TEO are classified as generally recognized as safe (GRAS) by the US Food and Drug Administration (FDA). This combination can be employed on the bell pepper packaging system to extend shelf life and oppose gray mold developments. Bell pepper fruits are normally coated with lipid-base coatings such as CW before commercialization; therefore, TEO addition would represent a small investment without any changes on the packaging system infrastructure.


Assuntos
Botrytis , Capsicum , Conservação de Alimentos , Frutas , Óleos Voláteis , Thymus (Planta) , Ceras , Botrytis/efeitos dos fármacos , Capsicum/microbiologia , Capsicum/química , Thymus (Planta)/química , Óleos Voláteis/farmacologia , Ceras/química , Ceras/farmacologia , Conservação de Alimentos/métodos , Frutas/microbiologia , Frutas/química , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Fungicidas Industriais/farmacologia
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