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Sample records for minimum fungicidal concentrations

  1. Activity of TDT 067 (terbinafine in Transfersome) against agents of onychomycosis, as determined by minimum inhibitory and fungicidal concentrations.

    Science.gov (United States)

    Ghannoum, Mahmoud; Isham, Nancy; Herbert, Jacqueline; Henry, William; Yurdakul, Sam

    2011-05-01

    TDT 067 is a novel carrier-based dosage form (liquid spray) of 15 mg/ml of terbinafine in Transfersome that has been developed to deliver terbinafine to the nail bed to treat onychomycosis. In this study, we report the in vitro activities of TDT 067 against dermatophytes, compared with those of the Transfersome vehicle, naked terbinafine, and commercially available terbinafine (1%) spray. The MICs of TDT 067 and comparators against 25 clinical strains each of Trichophyton rubrum, T. mentagrophytes, and Epidermophyton floccosum were determined according to the CLSI M38-A2 susceptibility method (2008). Minimum fungicidal concentrations (MFCs) were determined by subculturing visibly clear wells from the MIC microtiter plates. TDT 067 demonstrated potent activity against the dermatophyte strains tested, with an MIC range of 0.00003 to 0.015 μg/ml. Overall, TDT 067 MIC(50) values (defined as the lowest concentrations to inhibit 50% of the strains tested) were 8-fold and 60-fold lower than those of naked terbinafine and terbinafine spray, respectively. The Transfersome vehicle showed minimal inhibitory activity. TDT 067 demonstrated lower MFC values for T. rubrum and E. floccosum than naked terbinafine and terbinafine spray. TDT 067 has more potent antifungal activity against dermatophytes that cause nail infection than conventional terbinafine preparations. The Transfersome vehicle appears to potentiate the antifungal activity of terbinafine. Clinical investigation of TDT 067 for the topical treatment of onychomycosis is warranted.

  2. Effects of Fungicide Treatment on Free Amino Acid Concentration and Acrylamide-Forming Potential in Wheat.

    Science.gov (United States)

    Curtis, Tanya Y; Powers, Stephen J; Halford, Nigel G

    2016-12-28

    Acrylamide forms from free asparagine and reducing sugars during frying, baking, roasting, or high-temperature processing, and cereal products are major contributors to dietary acrylamide intake. Free asparagine concentration is the determining factor for acrylamide-forming potential in cereals, and this study investigated the effect of fungicide application on free asparagine accumulation in wheat grain. Free amino acid concentrations were measured in flour from 47 varieties of wheat grown in a field trial in 2011-2012. The wheat had been supplied with nitrogen and sulfur and treated with growth regulators and fungicides. Acrylamide formation was measured after the flour had been heated at 180 °C for 20 min. Flour was also analyzed from 24 (of the 47) varieties grown in adjacent plots that were treated in identical fashion except that no fungicide was applied, resulting in visible infection by Septoria tritici, yellow rust, and brown rust. Free asparagine concentration in the fungicide-treated wheat ranged from 1.596 to 3.987 mmol kg -1 , with a significant (p fungicide treatment, the increases in acrylamide ranging from 2.7 to 370%. Free aspartic acid concentration also increased, whereas free glutamic acid concentration increased in some varieties but decreased in others, and free proline concentration decreased. The study showed disease control by fungicide application to be an important crop management measure for mitigating the problem of acrylamide formation in wheat products.

  3. Activity of TDT 067 (Terbinafine in Transfersome) against Agents of Onychomycosis, as Determined by Minimum Inhibitory and Fungicidal Concentrations▿

    Science.gov (United States)

    Ghannoum, Mahmoud; Isham, Nancy; Herbert, Jacqueline; Henry, William; Yurdakul, Sam

    2011-01-01

    TDT 067 is a novel carrier-based dosage form (liquid spray) of 15 mg/ml of terbinafine in Transfersome that has been developed to deliver terbinafine to the nail bed to treat onychomycosis. In this study, we report the in vitro activities of TDT 067 against dermatophytes, compared with those of the Transfersome vehicle, naked terbinafine, and commercially available terbinafine (1%) spray. The MICs of TDT 067 and comparators against 25 clinical strains each of Trichophyton rubrum, T. mentagrophytes, and Epidermophyton floccosum were determined according to the CLSI M38–A2 susceptibility method (2008). Minimum fungicidal concentrations (MFCs) were determined by subculturing visibly clear wells from the MIC microtiter plates. TDT 067 demonstrated potent activity against the dermatophyte strains tested, with an MIC range of 0.00003 to 0.015 μg/ml. Overall, TDT 067 MIC50 values (defined as the lowest concentrations to inhibit 50% of the strains tested) were 8-fold and 60-fold lower than those of naked terbinafine and terbinafine spray, respectively. The Transfersome vehicle showed minimal inhibitory activity. TDT 067 demonstrated lower MFC values for T. rubrum and E. floccosum than naked terbinafine and terbinafine spray. TDT 067 has more potent antifungal activity against dermatophytes that cause nail infection than conventional terbinafine preparations. The Transfersome vehicle appears to potentiate the antifungal activity of terbinafine. Clinical investigation of TDT 067 for the topical treatment of onychomycosis is warranted. PMID:21411586

  4. In vitro Determination of Fungicide Inhibitory Concentration for Phakopsora pachyrhizi isolates

    Directory of Open Access Journals (Sweden)

    Bianca Moura

    2016-06-01

    Full Text Available ABSTRACT In vitro assays were preformed to obtain the IC50 of eight fungicides against Phakopsora pachyrhizi isolates from Passo Fundo, RS, Ponta Grossa, PR, and Primavera do Leste, MT. Different concentrations of the fungicides were added to Petri dishes containing soybean leaf extract agar medium. One milliliter of P. pachyrhizi uredospore suspension at the concentration of 3.0 x 104 uredospores/mL was added to each dish for subsequent viability quantification. Only pyraclostrobin and the mixture trifloxystrobin + prothioconazole showed IC50 values inferior to 1.0 mg/L for all tested isolates, demonstrating high fungitoxicity. There was not loss of sensitivity to any of the tested fungicides.

  5. Isoflurane minimum alveolar concentration reduction by fentanyl.

    Science.gov (United States)

    McEwan, A I; Smith, C; Dyar, O; Goodman, D; Smith, L R; Glass, P S

    1993-05-01

    Isoflurane is commonly combined with fentanyl during anesthesia. Because of hysteresis between plasma and effect site, bolus administration of fentanyl does not accurately describe the interaction between these drugs. The purpose of this study was to determine the MAC reduction of isoflurane by fentanyl when both drugs had reached steady biophase concentrations. Seventy-seven patients were randomly allocated to receive either no fentanyl or fentanyl at several predetermined plasma concentrations. Fentanyl was administered using a computer-assisted continuous infusion device. Patients were also randomly allocated to receive a predetermined steady state end-tidal concentration of isoflurane. Blood samples for fentanyl concentration were taken at 10 min after initiation of the infusion and before and immediately after skin incision. A minimum of 20 min was allowed between the start of the fentanyl infusion and skin incision. The reduction in the MAC of isoflurane by the measured fentanyl concentration was calculated using a maximum likelihood solution to a logistic regression model. There was an initial steep reduction in the MAC of isoflurane by fentanyl, with 3 ng/ml resulting in a 63% MAC reduction. A ceiling effect was observed with 10 ng/ml providing only a further 19% reduction in MAC. A 50% decrease in MAC was produced by a fentanyl concentration of 1.67 ng/ml. Defining the MAC reduction of isoflurane by all the opioids allows their more rational administration with inhalational anesthetics and provides a comparison of their relative anesthetic potencies.

  6. Effectiveness of control strategies against Botrytis cinerea in vineyard and evaluation of the residual fungicide concentrations.

    Science.gov (United States)

    Gabriolotto, Chiara; Monchiero, Matteo; Negre, Michele; Spadaro, Davide; Gullino, Maria Lodovica

    2009-05-01

    This investigation was undertaken to test different control strategies against Botrytis cinerea vineyards. Two commercial vineyards, "Barbera" and "Moscato," located in Piedmont (Northern Italy) were divided into seven plots and treated with different combinations of fungicides including fenhexamid, pyrimethanil, fludioxonil + cyprodinil, iprodione, and boscalid, a new carboxamide compound. An integrated strategy including a chemical (pyrimethanil) and a biocontrol agent (Trichoderma spp. t2/4ph1) was also included. At harvest, the percentage of bunches and berries attacked by B. cinerea and the concentration of the chemical fungicides were determined. All the pesticide residues at harvest were below the maximum residue level (MRL), except when two applications of pyrimethanil per season were applied. Boscalid was the most effective active ingredient against B. cinerea among the tested chemicals. When boscalid application was followed by a treatment with pyrimethanil, its efficacy was similar to that shown by two treatments of pyrimethanil. However, this second strategy was not feasible due to the risks of resistance development in the pathogen and to the residue accumulation as indicated by the analysis.

  7. Suggested benchmarks for shape optimization for minimum stress concentration

    DEFF Research Database (Denmark)

    Pedersen, Pauli

    2008-01-01

    Shape optimization for minimum stress concentration is vital, important, and difficult. New formulations and numerical procedures imply the need for good benchmarks. The available analytical shape solutions rely on assumptions that are seldom satisfied, so here, we suggest alternative benchmarks...

  8. 6 CFR 27.204 - Minimum concentration by security issue.

    Science.gov (United States)

    2010-01-01

    ... Section 27.204 Domestic Security DEPARTMENT OF HOMELAND SECURITY, OFFICE OF THE SECRETARY CHEMICAL FACILITY ANTI-TERRORISM STANDARDS Chemical Facility Security Program § 27.204 Minimum concentration by security issue. (a) Release Chemicals—(1) Release-Toxic Chemicals. If a release-toxic chemical of interest...

  9. The influence of particle size and AgNO3 concentration in the ionic exchange process on the fungicidal action of antimicrobial glass

    International Nuclear Information System (INIS)

    Mendes, E.; Piletti, R.; Barichello, T.; Oliveira, C.M.; Kniess, C.T.; Angioletto, E.; Riella, H.G.

    2012-01-01

    Antimicrobial materials have long been used as an effective means of reducing the risks posed to humans by fungi, bacteria and other microorganisms. These materials are essential in environments where cleanliness, comfort and hygiene are the predominate concerns. This work presents preliminary results for the development of a fungicidal vitreous material that is produced by the incorporation of a silver ionic specimen through ionic exchange reactions. Silver ions were incorporated into powdered glass via ionic exchange in an ionic medium containing silver species with different concentrations of AgNO 3 . The fungicidal efficiency of the samples was studied as a function of the AgNO 3 concentration and the particle size of the glass using the agar diffusion test for the microbiological analysis of the fungus species Candida albicans. The samples were examined by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The experimental results showed that the fungicidal effect was dependent on the AgNO 3 concentration in the ionic exchange medium but was not dependent on the particle size of the glass. - Highlights: ► The fungicidal powder glass presents high potential for application as polymeric additive and others application in the medical area. ► The fungicidal effect was dependent on AgNO3 concentration, but was not dependent on the particle size of the glass. ► The XRD results show that the ionic exchange process promotes the formation of silver crystalline phases with cubic cells.

  10. Minimum inhibitory concentration distribution in environmental Legionella spp. isolates.

    Science.gov (United States)

    Sandalakis, Vassilios; Chochlakis, Dimosthenis; Goniotakis, Ioannis; Tselentis, Yannis; Psaroulaki, Anna

    2014-12-01

    In Greece standard tests are performed in the watering and cooling systems of hotels' units either as part of the surveillance scheme or following human infection. The purpose of this study was to establish the minimum inhibitory concentration (MIC) distributions of environmental Legionella isolates for six antimicrobials commonly used for the treatment of Legionella infections, by MIC-test methodology. Water samples were collected from 2004 to 2011 from 124 hotels from the four prefectures of Crete (Greece). Sixty-eight (68) Legionella isolates, comprising L. pneumophila serogroups 1, 2, 3, 5, 6, 8, 12, 13, 15, L. anisa, L. rubrilucens, L. maceachernii, L. quinlivanii, L. oakridgensis, and L. taurinensis, were included in the study. MIC-tests were performed on buffered charcoal yeast extract with α-ketoglutarate, L-cysteine, and ferric pyrophosphate. The MICs were read after 2 days of incubation at 36 ± 1 °C at 2.5% CO2. A large distribution in MICs was recorded for each species and each antibiotic tested. Rifampicin proved to be the most potent antibiotic regardless of the Legionella spp.; tetracycline appeared to have the least activity on our environmental isolates. The MIC-test approach is an easy, although not so cost-effective, way to determine MICs in Legionella spp. These data should be kept in mind especially since these Legionella species may cause human disease.

  11. Minimum alveolar concentration threshold of sevoflurane for postoperative dream recall.

    Science.gov (United States)

    Aceto, P; Perilli, V; Lai, C; Sacco, T; Modesti, C; Luca, E; De Santis, P; Sollazzi, L; Antonelli, M

    2015-11-01

    Many factors affect postoperative dream recall, including patient characteristics, type of anesthesia, timing of postoperative interview and stress hormone secretion. Aims of the study were to determine whether Bispectral Index (BIS)-guided anesthesia might decrease sevoflurane minimum alveolar concentration (MAC) when compared with hemodynamically-guided anesthesia, and to search for a MAC threshold useful for preventing arousal, dream recall and implicit memory. One hundred thirty patients undergoing elective thyroidectomy were enrolled. Anesthesia was induced with propofol 2 mg kg(-1), fentanyl 3 mcg kg(-1) and cis-atracurium 0.15 mg kg(-1). For anesthesia maintenance, patients were randomly assigned to one of two groups: a BIS-guided group in which sevoflurane MAC was adjusted on the basis of BIS values, and a hemodynamic parameters (HP)-guided group in which MAC was adjusted based on HP. An auditory recording was presented to patients during anesthesia maintenance. Dream recall and explicit/implicit memory were investigated upon awakening and approximately after 24 h. Mean sevoflurane MAC during auditory presentation was similar in the two groups (0.85 ± 0.16 and 0.87 ± 0.17 [P = 0.53] in BIS-guided and HP-guided groups, respectively). Frequency of dream recall was similar in the two groups: 27% (N. = 17) in BIS-guided group, 18% (N. = 12) in HP-guided group, P = 0.37. In both groups, dream recall was less probable in patients anesthetized with MAC values ≥ 0.9 (area under ROC curve = 0.83, sensitivity = 90%, and specificity = 49%). BIS-guided anesthesia was not able to generate different MAC values compared to HP-guided anesthesia. Independent of the guide used for anesthesia, a sevoflurane MAC over 0.9 was required to prevent postoperative dream recall.

  12. Minimum alveolar concentration of isoflurane in green iguanas and the effect of butorphanol on minimum alveolar concentration.

    Science.gov (United States)

    Mosley, Craig A E; Dyson, Doris; Smith, Dale A

    2003-06-01

    To determine minimum alveolar concentration (MAC) of isoflurane in green iguanas and effects of butorphanol on MAC. Prospective randomized trial. 10 healthy mature iguanas. in each iguana, MAC was measured 3 times: twice after induction of anesthesia with isoflurane and once after induction of anesthesia with isoflurane and IM administration of butorphanol (1 mg/kg [0.45 mg/lb]). A blood sample was collected from the tail vein for blood-gas analysis at the beginning and end of the anesthetic period. The MAC was determined with a standard bracketing technique; an electrical current was used as the supramaximal stimulus. Animals were artificially ventilated with a ventilator set to deliver a tidal volume of 30 mL/kg (14 mL/lb) at a rate of 4 breaths/min. Mean +/- SD MAC values during the 3 trials (2 without and 1 with butorphanol) were 2.0 +/- 0.6, 2.1 +/- 0.6, and 1.7 +/- 0.7%, respectively, which were not significantly different from each other. Heart rate and end-tidal partial pressure of CO2 were also not significantly different among the 3 trials. Mean +/- SD heart rate was 48 +/- 10 beats/min; mean end-tidal partial pressure of CO2 was 22 +/- 10 mm Hg. There were no significant differences in blood-gas values for samples obtained at the beginning versus the end of the anesthetic period. Results suggest that the MAC of isoflurane in green iguanas is 2.1% and that butorphanol does not have any significant isoflurane-sparing effects.

  13. Effect of tomato post-harvest fungicide treatment and storage conditions on the quality of fruits, and biological value of tomato pulp and concentrated pulp

    Directory of Open Access Journals (Sweden)

    H. Parynow

    2013-12-01

    Full Text Available The influence of storage conditions on the quality of tomato fruits was tested. The rate of ripening was established in normal air, where tomatoes ripen quickly, under controlled atmosphere where they ripen more slowly and under low pressure, where they ripen slowest. The influence of post-harvest benomyl or methylthiophanate treatment on tomato rot, ripening, and biological value were examined. Post-harvest tomato treatment did not reduce fruit rot. The color of fruits and the processed products depended on the fungicide treatment. Concentrated tomato pulp made of fruits treated with methylthiophanate was redder than the others. The fungicide treatment increased or decreased the level of some chemical substances in the fruits in dependence on the applied fungicide, storage conditions and the length of storage, e.g. tomatoes treated with benomyl and stored for 14 days contained the highest level of vitamin C under 0% CO2:3%O2 and tomatoes treated with methylthiophanate contained the highest level of vitamin C under 38 mm Hg. Degradation of vitamin C in pulp was faster than in the concentrated pulp. Tomato pulp made of tomatoes treated with methylthiophanate contained the lowest level of vitamin C.

  14. Minimum inhibitory concentration values and problematic disk break ...

    African Journals Online (AJOL)

    Latife Ä°ÅŸeri

    2015-08-08

    Aug 8, 2015 ... to tigecycline, and to test the correlation between the minimal inhibitory concentration (MIC) and ... This study was performed using 108 strains of enterococci. The .... drugs (TetA-E, TetK) from inside the bacterial cell, and ribo-.

  15. Determination of minimum inhibitory and minimum bactericidal concentrations of tiamulin against field isolates of Actinobacillus pleuropneumoniae.

    Science.gov (United States)

    Pridmore, Andrew; Burch, David; Lees, Peter

    2011-08-05

    Tiamulin activity was measured against 19 UK field isolates of Actinobacillus pleuropneumoniae collected between 2003 and 2009 and the type strain ATCC 27090 as a control, with the intention of comparing broth with serum as growth media. Broth microdilution MIC/MBC tests were performed in accordance with the Clinical and Laboratory Standards Institute (CLSI) guideline M31-A3, in 'Veterinary Fastidious Medium' (VFM) (supplemented Mueller-Hinton broth at pH 7.3) and in 100% swine serum. For improved precision, a modified, overlapping doubling-dilution series was used (tiamulin concentration range 0.3-72 μg/ml). The MBC was reported as the lowest concentration producing a 99.9% reduction in bacterial density in the sub-cultured well contents, relative to the starting inoculum. The mean MBC/MIC ratio for tiamulin against A. pleuropneumoniae in VFM was low (1.74:1), even though tiamulin is classed as a bacteriostatic drug. Only three of the 19 isolates and the reference strain grew in 100% serum and their MICs were higher than those determined in VFM. It is postulated that this difference was due to differences in pH of the matrices or binding of tiamulin to serum proteins or a combination of both factors. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Minimum inhibitory concentration of Brazilian Brachyspira hyodysenteriae strains

    OpenAIRE

    Daniel, Amanda G.S.; Sato, José P.H.; Gabardo, Michelle P.; Resende, Talita P.; Barcellos, David E.S.N. de; Pereira, Carlos E.R.; Vannucci, Fábio A.; Guedes, Roberto M.C.

    2017-01-01

    ABSTRACT: The objectives of this study were to characterize Brachyspira hyodysenteriae isolates and to evaluate the antimicrobial susceptibility patterns of strains obtained from pigs in Brazil based on the minimal inhibitory concentration test (MIC). The MIC was performed for 22 B. hyodysenteriae isolates obtained from 2011 to 2013 using the following antimicrobial drugs: tylosin, tiamulin, valnemulin, doxycycline, lincomycin and tylvalosin. Outbreaks of swine dysentery were diagnosed based ...

  17. Sensibilidade de Colletotrichum gloeosporioides (mancha manteigosa do cafeeiro a diferentes concentrações de fungicidas Sensibility of Colletotrichum gloeosporioides (coffee blister spot to different fungicide concentrations

    Directory of Open Access Journals (Sweden)

    Josimar Batista Ferreira

    2009-01-01

    Full Text Available Com o objetivo de avaliar a eficiência de alguns fungicidas sobre Colletotrichum gloeosporioides, agente etiológico da mancha manteigosa do cafeeiro (Coffea arabica L., testes in vitro foram conduzidos no Laboratório de Diagnose e Controle/UFLA. Utilizou-se o método de incorporação de fungicidas ao meio de cultura MEA 2% para a avaliação da inibição do crescimento micelial e em lâmina escavada contendo água com fungicida para a germinação de conídios. Os fungicidas, tetraconazol, triadimenol, chlorotalonil e mancozeb foram testados quanto à inibição do crescimento do micelial (nas concentrações de 1, 5, 10, 25, 50, 100, 500 e 1.000 mg L-1 e quanto à inibição da germinação de conídios (nas concentrações de 1, 5, 10, 25, 50 e 100 mg L-1. Os fungicidas tetraconazol e triadimenol apresentaram alta eficiência na inibição do crescimento micelial. Os fungicidas chlorotalonil e mancozeb mostraram baixa eficiência e ineficiência, respectivamente. Quanto à germinação dos conídios, os fungicidas que demonstraram maior eficiência em baixas concentrações foram o chlorotalonil e o tetraconazol.With the aim of assessing the effect of selected fungicides on Colletotrichum gloeosporioides, the cause of coffee blister spot, in vitro tests were carried out in the Laboratory of Diagnosis and Control/UFLA, Federal University of Lavras, Brazil. In the in vitro experiments the fungicides were incorporated into malt extract medium (MEA 2% to evaluate the effect on the fungus growth rate, and concavity slides containing water plus fungicide to assess the conidia germination. The fungicides tetraconazol, triadimenol, chlorothalonil and mancozeb were tested on the mycelial growth inhibition (in the concentrations of 1, 5, 10, 25, 50, 100, 500 and 1.000 mg L-1 and on the inhibition conidia germination (in the concentrations of 1, 5, 10, 25, 50 e 100 mg L-1. The fungicides tetraconazol and triadimenol showed high efficiency on the

  18. Minimum inhibitory concentration of Brazilian Brachyspira hyodysenteriae strains

    Directory of Open Access Journals (Sweden)

    Amanda G.S. Daniel

    Full Text Available ABSTRACT: The objectives of this study were to characterize Brachyspira hyodysenteriae isolates and to evaluate the antimicrobial susceptibility patterns of strains obtained from pigs in Brazil based on the minimal inhibitory concentration test (MIC. The MIC was performed for 22 B. hyodysenteriae isolates obtained from 2011 to 2013 using the following antimicrobial drugs: tylosin, tiamulin, valnemulin, doxycycline, lincomycin and tylvalosin. Outbreaks of swine dysentery were diagnosed based on clinical presentation, bacterial isolation, gross and microscopic lesions, duplex PCR for B. hyodysenteriae and B. pilosicoli and nox gene sequencing. All obtained MIC values were consistently higher or equal to the microbiological cut-off described in the literature. The MIC 90 values for the tested drugs were 8μg/ml for doxycycline, >4μg/ml for valnemulin, 8μg/ml for tiamulin, 32μg/ml for tylvalosin, >64μg/ml for lincomycin and >128μg/ml for tylosin. These results largely corroborate those reported in the literature. Tiamulin, doxycycline and tylvalosin showed the lowest MIC results. All of the samples subjected to phylogenetic analysis based on the nox gene sequence exhibited similar results, showing 100% identity to B. hyodysenteriae. This is the first study describing the MIC pattern of B. hyodysenteriae isolated in Brazil.

  19. Standardization of a broth microdilution susceptibility testing method to determine minimum inhibitory concentrations of aquatic bacteria

    DEFF Research Database (Denmark)

    Miller, R.A.; Walker, R.D.; Carson, J.

    2005-01-01

    (ampicillin, enrofloxacin, erythromycin, florfenicol, flumequine, gentamicin, ormetoprim/sulfadimethoxine, oxolinic acid, oxytetracycline and trimethoprim/sulfamethoxazole). Minimum inhibitory concentration (MIC) QC ranges were determined using dry- and frozen-form 96-well plates and cation-adjusted Mueller...

  20. Hypnosis control based on the minimum concentration of anesthetic drug for maintaining appropriate hypnosis.

    Science.gov (United States)

    Furutani, Eiko; Nishigaki, Yuki; Kanda, Chiaki; Takeda, Toshihiro; Shirakami, Gotaro

    2013-01-01

    This paper proposes a novel hypnosis control method using Auditory Evoked Potential Index (aepEX) as a hypnosis index. In order to avoid side effects of an anesthetic drug, it is desirable to reduce the amount of an anesthetic drug during surgery. For this purpose many studies of hypnosis control systems have been done. Most of them use Bispectral Index (BIS), another hypnosis index, but it has problems of dependence on anesthetic drugs and nonsmooth change near some particular values. On the other hand, aepEX has an ability of clear distinction between patient consciousness and unconsciousness and independence of anesthetic drugs. The control method proposed in this paper consists of two elements: estimating the minimum effect-site concentration for maintaining appropriate hypnosis and adjusting infusion rate of an anesthetic drug, propofol, using model predictive control. The minimum effect-site concentration is estimated utilizing the property of aepEX pharmacodynamics. The infusion rate of propofol is adjusted so that effect-site concentration of propofol may be kept near and always above the minimum effect-site concentration. Simulation results of hypnosis control using the proposed method show that the minimum concentration can be estimated appropriately and that the proposed control method can maintain hypnosis adequately and reduce the total infusion amount of propofol.

  1. Biofilm formation and determination of minimum biofilm eradication concentration of antibiotics in Mycoplasma hyopneumoniae.

    Science.gov (United States)

    Tassew, Dereje Damte; Mechesso, Abraham Fikru; Park, Na-Hye; Song, Ju-Beom; Shur, Joo-Woon; Park, Seung-Chun

    2017-10-20

    The study was aimed to investigate biofilm forming ability of Mycoplasma hyopneumoniae and to determine the minimum biofilm eradication concentrations of antibiotics. Biofilm forming ability of six strains of M. hyopneumoniae was examined using crystal violet staining on coverslips. The results demonstrated an apparent line of biofilm growth in 3 of the strains isolated from swine with confirmed cases of enzootic pneumonia. BacLight bacterial viability assay revealed that the majority of the cells were viable after 336 hr of incubation. Moreover, M. hyopneumoniae persists in the biofilm after being exposed to 10 fold higher concentration of antibiotics than the minimum inhibitory concentrations in planktonic cells. To the best of our knowledge, this is the first report of biofilm formation in M. hyopneumoniae. However, comprehensive studies on the mechanisms of biofilm formation are needed to combat swine enzootic pneumonia caused by resistant M. hyopneumoniae.

  2. How low can you go? Assessing minimum concentrations of NSC in carbon limited tree saplings

    Science.gov (United States)

    Hoch, Guenter; Hartmann, Henrik; Schwendener, Andrea

    2016-04-01

    Tissue concentrations of non-structural carbohydrates (NSC) are frequently used to determine the carbon balance of plants. Over the last years, an increasing number of studies have inferred carbon starvation in trees under environmental stress like drought from low tissue NSC concentrations. However, such inferences are limited by the fact that minimum concentrations of NSC required for survival are not known. So far, it was hypothesized that even under lethal carbon starvation, starch and low molecular sugar concentrations cannot be completely depleted and that minimum NSC concentrations at death vary across tissues and species. Here we present results of an experiment that aimed to determine minimum NSC concentrations in different tissues of saplings of two broad-leaved tree species (Acer pseudoplatanus and Quercus petratea) exposed to lethal carbon starvation via continuous darkening. In addition, we investigated recovery rates of NSC concentrations in saplings that had been darkened for different periods of time and were then re-exposed to light. Both species survived continuous darkening for about 12 weeks (confirmed by testing the ability to re-sprout after darkness). In all investigated tissues, starch concentrations declined close to zero within three to six weeks of darkness. Low molecular sugars also decreased strongly within the first weeks of darkness, but seemed to stabilize at low concentrations of 0.5 to 2 % dry matter (depending on tissue and species) almost until death. NSC concentrations recovered surprisingly fast in saplings that were re-exposed to light. After 3 weeks of continuous darkness, tissue NSC concentrations recovered within 6 weeks to levels of unshaded control saplings in all tissues and in both species. To our knowledge, this study represents the first experimental attempt to quantify minimum tissue NSC concentrations at lethal carbon starvation. Most importantly, our results suggest that carbon-starved tree saplings are able to

  3. Evaluation of the minimum iodine concentration for contrast-enhanced subtraction mammography

    International Nuclear Information System (INIS)

    Baldelli, P; Bravin, A; Maggio, C Di; Gennaro, G; Sarnelli, A; Taibi, A; Gambaccini, M

    2006-01-01

    Early manifestation of breast cancer is often very subtle and is displayed in a complex and variable pattern of normal anatomy that may obscure the disease. The use of dual-energy techniques, that can remove the structural noise, and contrast media, that enhance the region surrounding the tumour, could help us to improve the detectability of the lesions. The aim of this work is to investigate the use of an iodine-based contrast medium in mammography with two different double exposure techniques: K-edge subtraction mammography and temporal subtraction mammography. Both techniques have been investigated by using an ideal source, like monochromatic beams produced at a synchrotron radiation facility and a clinical digital mammography system. A dedicated three-component phantom containing cavities filled with different iodine concentrations has been developed and used for measurements. For each technique, information about the minimum iodine concentration, which provides a significant enhancement of the detectability of the pathology by minimizing the risk due to high dose and high concentration of contrast medium, has been obtained. In particular, for cavities of 5 and 8 mm in diameter filled with iodine solutions, the minimum concentration needed to obtain a contrast-to-noise ratio of 5 with a mean glandular dose of 2 mGy has been calculated. The minimum concentrations estimated with monochromatic beams and K-edge subtraction mammography are 0.9 mg ml -1 and 1.34 mg ml -1 for the biggest and smallest details, respectively, while for temporal subtraction mammography they are 0.84 mg ml -1 and 1.31 mg ml -1 . With the conventional clinical system the minimum concentrations for the K-edge subtraction mammography are 4.13 mg ml -1 (8 mm diameter) and 5.75 mg ml -1 (5 mm diameter), while for the temporal subtraction mammography they are 1.01 mg ml -1 (8 mm diameter) and 1.57 mg ml -1 (5 mm diameter)

  4. Minimum detectable gas concentration performance evaluation method for gas leak infrared imaging detection systems.

    Science.gov (United States)

    Zhang, Xu; Jin, Weiqi; Li, Jiakun; Wang, Xia; Li, Shuo

    2017-04-01

    Thermal imaging technology is an effective means of detecting hazardous gas leaks. Much attention has been paid to evaluation of the performance of gas leak infrared imaging detection systems due to several potential applications. The minimum resolvable temperature difference (MRTD) and the minimum detectable temperature difference (MDTD) are commonly used as the main indicators of thermal imaging system performance. This paper establishes a minimum detectable gas concentration (MDGC) performance evaluation model based on the definition and derivation of MDTD. We proposed the direct calculation and equivalent calculation method of MDGC based on the MDTD measurement system. We build an experimental MDGC measurement system, which indicates the MDGC model can describe the detection performance of a thermal imaging system to typical gases. The direct calculation, equivalent calculation, and direct measurement results are consistent. The MDGC and the minimum resolvable gas concentration (MRGC) model can effectively describe the performance of "detection" and "spatial detail resolution" of thermal imaging systems to gas leak, respectively, and constitute the main performance indicators of gas leak detection systems.

  5. Mycotoxin and fungicide residues in wheat grains from fungicide-treated plants measured by a validated LC-MS method.

    Science.gov (United States)

    da Luz, Suzane Rickes; Pazdiora, Paulo Cesar; Dallagnol, Leandro José; Dors, Giniani Carla; Chaves, Fábio Clasen

    2017-04-01

    Wheat (Triticum aestivum) is an annual crop, cultivated in the winter and spring and susceptible to several pathogens, especially fungi, which are managed with fungicides. It is also one of the most consumed cereals, and can be contaminated by mycotoxins and fungicides. The objective of this study was to validate an analytical method by LC-MS for simultaneous determination of mycotoxins and fungicide residues in wheat grains susceptible to fusarium head blight treated with fungicides, and to evaluate the relationship between fungicide application and mycotoxin production. All parameters of the validated analytical method were within AOAC and ANVISA limits. Deoxynivalenol was the prevalent mycotoxin in wheat grain and epoxiconazole was the fungicide residue found in the highest concentration. All fungicidal treatments induced an increase in AFB2 production when compared to the control (without application). AFB1 and deoxynivalenol, on the contrary, were reduced in all fungicide treatments compared to the control. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Dosing strategy based on prevailing aminoglycoside minimum inhibitory concentration in India: Evidence and issues

    Directory of Open Access Journals (Sweden)

    Balaji Veeraraghavan

    2017-01-01

    Full Text Available Aminoglycosides are important agents used for treating drug-resistant infections. The current dosing regimen of aminoglycosides does not achieve sufficient serum level concentration for the infected bacterial pathogen interpreted as susceptible based on laboratory testing. Minimum inhibitory concentration was determined for nearly 2000 isolates of Enterobacteriaceae and Pseudomonas aeruginosa by broth microdilution method. Results were interpreted based on CLSI and EUCAST interpretative criteria and the inconsistencies in the susceptibility profile were noted. This study provides insights into the inconsistencies existing in the laboratory interpretation and the corresponding clinical success rates. This urges the need for revising clinical breakpoints for amikacin, to resolve under dosing leading to clinical failure.

  7. Technical basis for a minimum hydroxide concentration in tanks containing dilute waste

    International Nuclear Information System (INIS)

    Zapp, P.E.

    1995-05-01

    Laboratory tests were performed to address the protection of waste tank steel from corrosion in situations of elevated temperatures up to 75 C (hot spots) in the sludge layer of Extended Sludge Processing (ESP) tanks. Coupon immersion tests were conducted at 75 C in two ESP simulants at four hydroxide (or pH) levels. The nitrite concentrations of the simulants were calculated from the ESP technical standards based on a temperature of 40 C. The results showed that a hydroxide concentration of at least 0.01 M prevented significant corrosion of the steel at the elevated temperature. This conclusion provides the technical basis for the revised minimum hydroxide concentration of 0.01 M in the draft WSRC 241-82H Control Room Process Requirements, for the ESP tanks

  8. Effects of carprofen and morphine on the minimum alveolar concentration of isoflurane in dogs.

    Science.gov (United States)

    Ko, Jeff C H; Weil, Ann B; Inoue, Tomohito

    2009-01-01

    The minimum alveolar concentration (MAC) of isoflurane in dogs was determined following carprofen (2.2 mg/kg per os) alone, morphine (1 mg/kg intravenously) alone, carprofen and morphine, and no drug control in eight healthy adult dogs. Isoflurane MAC following administration of morphine alone (0.81%+/-0.18%) or carprofen and morphine (0.68%+/-0.31%) was significantly less than the control MAC (1.24%+/-0.15%). Isoflurane MAC after carprofen alone (1.13%+/-0.13%) was not significantly different from the control value. Results indicated that administration of morphine alone or in combination with carprofen significantly reduced the MAC of isoflurane in dogs. The isoflurane MAC reduction was additive between the effects of carprofen and morphine.

  9. Grape berry bacterial inhibition by different copper fungicides

    Directory of Open Access Journals (Sweden)

    Martins Guilherme

    2016-01-01

    Full Text Available Copper fungicides are widely used in viticulture. Due to its large spectrum of action, copper provides an efficient control over a great number of vine pathogens. Previous studies showed that, high levels of cupric residues can impact grape-berry microbiota, in terms of the size and population structure, reducing the diversity and the abundance. Due to the importance of grape-berry bacterial in crop health, and the potential impact of copper fungicides over the microbiota, we determined Minimum Inhibitory Concentration (MIC of different copper formulations for bacterial species isolated from grape berries. We study the Minimum Inhibitory Concentration (MIC of different copper formulations (copper sulphate (CuSO4 pure, Bordeaux mixture (CuSO4 + Ca(OH2, copper oxide (Cu2O, copper hydroxide (Cu(OH2 over 92 bacterial strains isolated from grape berries in different stages of the ripening process. The results of MIC measurements revealed that the different copper formulations have a variable inhibitory effect and among the different isolates, some species are the most resistant to all copper formulations than others. This study confirm that usage of cupric phytosanitary products should be reasonable independently of the farming system; they also provide evidence of the importance of the choice of which copper formulations are to be used regarding their impact on the grape berry bacterial microbiota.

  10. Minimum inhibitory concentrations of medicinal plants used in Northern Peru as antibacterial remedies.

    Science.gov (United States)

    Bussmann, R W; Malca-García, G; Glenn, A; Sharon, D; Chait, G; Díaz, D; Pourmand, K; Jonat, B; Somogy, S; Guardado, G; Aguirre, C; Chan, R; Meyer, K; Kuhlman, A; Townesmith, A; Effio-Carbajal, J; Frías-Fernandez, F; Benito, M

    2010-10-28

    The plant species reported here are traditionally used in Northern Peru to treat bacterial infections, often addressed by the local healers as "inflammation". The aim of this study was to evaluate the minimum inhibitory concentration (MIC) of their antibacterial properties against gram-positive and gram-negative bacteria. The antimicrobial activity of ethanolic and water extracts of 141 plant species was determined using a deep-well broth microdilution method on commercially available bacterial strains. The ethanolic extracts of 51 species inhibited Escherichia coli, and 114 ethanolic extracts inhibited Staphylococcus aureus. In contrast, only 30 aqueous extracts showed activity against Escherichia coli and 38 extracts against Staphylococcus aureus. The MIC concentrations were mostly very high and ranged from 0.008 to 256 mg/ml, with only 36 species showing inhibitory concentrations of extracts exhibited stronger activity and a much broader spectrum of action than the aqueous extracts. Hypericum laricifolium, Hura crepitans, Caesalpinia paipai, Cassia fistula, Hyptis sidifolia, Salvia sp., Banisteriopsis caapi, Miconia salicifolia and Polygonum hydropiperoides showed the lowest MIC values and would be interesting candidates for future research. The presence of antibacterial activity could be confirmed in most species used in traditional medicine in Peru which were assayed in this study. However, the MIC for the species employed showed a very large range, and were mostly very high. Nevertheless, traditional knowledge might provide some leads to elucidate potential candidates for future development of new antibiotic agents. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  11. Estimation of minimum detectable concentration of chlorine in the blast furnace slag cement concrete

    Energy Technology Data Exchange (ETDEWEB)

    Naqvi, A.A., E-mail: aanaqvi@kfupm.edu.s [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Maslehuddin, M. [Center for Engineering Research, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Garwan, M.A.; Nagadi, M.M. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Al-Amoudi, O.S.B. [Department of Civil Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Khateeb-ur-Rehman,; Raashid, M. [Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

    2011-01-01

    The Prompt Gamma Neutron Activation Analysis technique was used to measure the concentration of chloride in the blast furnace slag (BFS) cement concrete to assess the possibility of reinforcement corrosion. The experimental setup was optimized using Monte Carlo calculations. The BFS concrete specimens containing 0.8-3.5 wt.% chloride were prepared and the concentration of chlorine was evaluated by determining the yield of 6.11, 6.62, 7.41, 7.79 and 8.58 MeV gamma-rays. The Minimum Detectable Concentration (MDC) of chlorine in the BFS cement concrete was estimated. The best value of MDC limit of chlorine in the BFS cement concrete was found to be 0.034 {+-} 0.011 and 0.038 {+-} 0.012 wt.% for 6.11 and 6.62 MeV prompt gamma-rays. Within the statistical uncertainty the lower bound of the measured MDC of chlorine in the BFS cement concrete meets the maximum permissible limit of 0.03 wt.% of chloride set by the American Concrete Institute.

  12. Effects of fentanyl on isoflurane minimum alveolar concentration in New Zealand White rabbits (Oryctolagus cuniculus).

    Science.gov (United States)

    Barter, Linda S; Hawkins, Michelle G; Pypendop, Bruno H

    2015-02-01

    To determine effects of increasing plasma fentanyl concentrations on the minimum alveolar concentration (MAC) of isoflurane in rabbits. 6 adult female New Zealand White rabbits (Oryctolagus cuniculus). Rabbits were anesthetized with isoflurane in oxygen; ventilation was controlled and body temperature maintained between 38.5° and 39.5°C. Fentanyl was administered IV by use of a computer-controlled infusion system to achieve 6 target plasma concentrations. Isoflurane MAC was determined in duplicate by use of the bracketing technique with a supramaximal electrical stimulus. Blood samples were collected for measurement of plasma fentanyl concentration at each MAC determination. The MAC values were analyzed with a repeated-measures ANOVA followed by Holm-Sidak pairwise comparisons. Mean ± SD plasma fentanyl concentrations were 0 ± 0 ng/mL (baseline), 1.2 ± 0.1 ng/mL, 2.2 ± 0.3 ng/mL, 4.4 ± 0.4 ng/mL, 9.2 ± 0.4 ng/mL, 17.5 ± 2.6 ng/mL, and 36.8 ± 2.4 ng/mL. Corresponding mean values for isoflurane MAC were 1.92 ± 0.16%, 1.80 ± 0.16%, 1.60 ± 0.23%, 1.46 ± 0.22%, 1.12 ± 0.19%, 0.89 ± 0.14%, and 0.70 ± 0.15%, respectively. Isoflurane MAC for plasma fentanyl concentrations ≥ 2.2 ng/mL differed significantly from the baseline value. In 3 rabbits, excessive spontaneous movement prevented MAC determination at the highest plasma fentanyl concentration. Fentanyl reduced isoflurane MAC by approximately 60% in New Zealand White rabbits. Further studies will be needed to investigate the cardiorespiratory effects of isoflurane and fentanyl combinations in rabbits; however, fentanyl may prove to be a useful adjunct to inhalation anesthesia in this species.

  13. Lidocaine, dexmedetomidine and their combination reduce isoflurane minimum alveolar concentration in dogs.

    Directory of Open Access Journals (Sweden)

    Carlos M Acevedo-Arcique

    Full Text Available The effects of intravenous (i.v. lidocaine, dexmedetomidine and their combination delivered as a bolus followed by a constant rate infusion (CRI on the minimum alveolar concentration of isoflurane (MACISO in dogs were evaluated. Seven healthy adult dogs were included. Anaesthesia was induced with propofol and maintained with isoflurane. For each dog, baseline MAC (MACISO/BASAL was determined after a 90-minute equilibration period. Thereafter, each dog received one of the following treatments (loading dose, CRI: lidocaine 2 mg kg(-1, 100 µg kg(-1 minute(-1; dexmedetomidine 2 µg kg(-1, 2 µg kg(-1 hour(-1; or their combination. MAC was then determined again after 45- minutes of treatment by CRI. At the doses administered, lidocaine, dexmedetomidine and their combination significantly reduced MACISO by 27.3% (range: 12.5-39.2%, 43.4% (33.3-53.3% and 60.9% (46.1-78.1%, respectively, when compared to MACISO/BASAL. The combination resulted in a greater MACISO reduction than the two drugs alone. Their use, at the doses studied, provides a clinically important reduction in the concentration of ISO during anaesthesia in dogs.

  14. Effect of intravenous administration of tramadol hydrochloride on the minimum alveolar concentration of isoflurane in rabbits.

    Science.gov (United States)

    Egger, Christine M; Souza, Marcy J; Greenacre, Cheryl B; Cox, Sherry K; Rohrbach, Barton W

    2009-08-01

    To evaluate the effect of IV administration of tramadol hydrochloride on the minimum alveolar concentration of isoflurane (ISOMAC) that prevented purposeful movement of rabbits in response to a noxious stimulus. Six 6- to 12-month-old female New Zealand White rabbits. Anesthesia was induced and maintained with isoflurane in oxygen. A baseline ISOMAC was determined by clamping a pedal digit with sponge forceps until gross purposeful movement was detected or a period of 60 seconds elapsed. Subsequently, tramadol (4.4 mg/kg) was administered IV and the posttreatment ISOMAC (ISOMAC(T)) was measured. Mean +/- SD ISOMAC and ISOMAC(T) values were 2.33 +/- 0.13% and 2.12 +/- 0.17%, respectively. The ISOMAC value decreased by 9 +/- 4% after tramadol was administered. Plasma tramadol and its major metabolite (M1) concentrations at the time of ISOMAC(T) determination varied widely (ranges, 181 to 636 ng/mL and 32 to 61 ng/mL, respectively). Intervals to determination of ISOMAC(T) and plasma tramadol and M1 concentrations were not correlated with percentage change in the ISOMAC. Heart rate decreased significantly immediately after tramadol administration but by 10 minutes afterward was not different from the pretreatment value. Systolic arterial blood pressure decreased to approximately 60 mm Hg for approximately 5 minutes in 3 rabbits after tramadol administration. No adverse effects were detected. As administered, tramadol had a significant but clinically unimportant effect on the ISOMAC in rabbits. Higher doses of tramadol may provide clinically important reductions but may result in a greater degree of cardiovascular depression.

  15. Medium Effects on Minimum Inhibitory Concentrations of Nylon-3 Polymers against E. coli

    Science.gov (United States)

    Choi, Heejun; Chakraborty, Saswata; Liu, Runhui; Gellman, Samuel H.; Weisshaar, James C.

    2014-01-01

    Minimum inhibitory concentrations (MICs) against E. coli were measured for three nylon-3 polymers using Luria-Bertani broth (LB), brain-heart infusion broth (BHI), and a chemically defined complete medium (EZRDM). The polymers differ in the ratio of hydrophobic to cationic subunits. The cationic homopolymer is inert against E. coli in BHI and LB, but becomes highly potent in EZRDM. A mixed hydrophobic/cationic polymer with a hydrophobic t-butylbenzoyl group at its N-terminus is effective in BHI, but becomes more effective in EZRDM. Supplementation of EZRDM with the tryptic digest of casein (often found in LB) recapitulates the LB and BHI behavior. Additional evidence suggests that polyanionic peptides present in LB and BHI may form electrostatic complexes with cationic polymers, decreasing activity by diminishing binding to the anionic lipopolysaccharide layer of E. coli. In contrast, two natural antimicrobial peptides show no medium effects. Thus, the use of a chemically defined medium helps to reveal factors that influence antimicrobial potency of cationic polymers and functional differences between these polymers and evolved antimicrobial peptides. PMID:25153714

  16. Whole Genome Sequence Analysis of Pig Respiratory Bacterial Pathogens with Elevated Minimum Inhibitory Concentrations for Macrolides.

    Science.gov (United States)

    Dayao, Denise Ann Estarez; Seddon, Jennifer M; Gibson, Justine S; Blackall, Patrick J; Turni, Conny

    2016-10-01

    Macrolides are often used to treat and control bacterial pathogens causing respiratory disease in pigs. This study analyzed the whole genome sequences of one clinical isolate of Actinobacillus pleuropneumoniae, Haemophilus parasuis, Pasteurella multocida, and Bordetella bronchiseptica, all isolated from Australian pigs to identify the mechanism underlying the elevated minimum inhibitory concentrations (MICs) for erythromycin, tilmicosin, or tulathromycin. The H. parasuis assembled genome had a nucleotide transition at position 2059 (A to G) in the six copies of the 23S rRNA gene. This mutation has previously been associated with macrolide resistance but this is the first reported mechanism associated with elevated macrolide MICs in H. parasuis. There was no known macrolide resistance mechanism identified in the other three bacterial genomes. However, strA and sul2, aminoglycoside and sulfonamide resistance genes, respectively, were detected in one contiguous sequence (contig 1) of A. pleuropneumoniae assembled genome. This contig was identical to plasmids previously identified in Pasteurellaceae. This study has provided one possible explanation of elevated MICs to macrolides in H. parasuis. Further studies are necessary to clarify the mechanism causing the unexplained macrolide resistance in other Australian pig respiratory pathogens including the role of efflux systems, which were detected in all analyzed genomes.

  17. Ammonium and nitrite oxidation at nanomolar oxygen concentrations in oxygen minimum zone waters.

    Science.gov (United States)

    Bristow, Laura A; Dalsgaard, Tage; Tiano, Laura; Mills, Daniel B; Bertagnolli, Anthony D; Wright, Jody J; Hallam, Steven J; Ulloa, Osvaldo; Canfield, Donald E; Revsbech, Niels Peter; Thamdrup, Bo

    2016-09-20

    A major percentage of fixed nitrogen (N) loss in the oceans occurs within nitrite-rich oxygen minimum zones (OMZs) via denitrification and anammox. It remains unclear to what extent ammonium and nitrite oxidation co-occur, either supplying or competing for substrates involved in nitrogen loss in the OMZ core. Assessment of the oxygen (O2) sensitivity of these processes down to the O2 concentrations present in the OMZ core (Chile at manipulated O2 levels between 5 nmol⋅L(-1) and 20 μmol⋅L(-1) Rates of both processes were detectable in the low nanomolar range (5-33 nmol⋅L(-1) O2), but demonstrated a strong dependence on O2 concentrations with apparent half-saturation constants (Kms) of 333 ± 130 nmol⋅L(-1) O2 for ammonium oxidation and 778 ± 168 nmol⋅L(-1) O2 for nitrite oxidation assuming one-component Michaelis-Menten kinetics. Nitrite oxidation rates, however, were better described with a two-component Michaelis-Menten model, indicating a high-affinity component with a Km of just a few nanomolar. As the communities of ammonium and nitrite oxidizers were similar to other OMZs, these kinetics should apply across OMZ systems. The high O2 affinities imply that ammonium and nitrite oxidation can occur within the OMZ core whenever O2 is supplied, for example, by episodic intrusions. These processes therefore compete with anammox and denitrification for ammonium and nitrite, thereby exerting an important control over nitrogen loss.

  18. Sensitivity of Septoria pyricola isolates to carbendazim, DMI and QoI based fungicides and to boscalid, in Greece

    Directory of Open Access Journals (Sweden)

    Athanassios Christos PAPPAS

    2010-09-01

    Full Text Available The sensitivity of 36 Septoria pyricola single spore isolates, obtained from isolated pear orchards, to carbendazim, bitertanol, flusilazole, myclobutanil, azoxystrobin, kresoxim-methyl, pyraclostrobin, trifloxystrobin and boscalid, was studied in vitro. Spore suspensions were point-inoculated on media amended with various concentrations of fungicides and the minimum inhibitory concentration (MICs of the fungicides was determined. Most isolates were highly resistant to carbendazim, forming colonies even at concentrations of 100 mg L-1 of the fungicide. A few isolates failed to form colonies with carbendazim concentrations of 0.1 and 10 mg L-1; these isolates were designated carbendazim-sensitive and moderately carbendazim-resistant respectively.The MIC of DMI fungicides was up to 1 mg L-1 with some isolates, and the mean MICs of bitertanol, flusilazole and myclobutanil were 0.133±0.036, 0.075±0.044 and 0.230±0.038 mg L-1 respectively. The MIC of the QoI fungicides was up to 0.1 mg L-1 with most isolates, but some isolates were 100-fold less sensitive to azoxystrobin. The mean MICs of azoxystrobin, kresoxim-methyl, pyraclostrobin and trifloxystrobin were 0.177±0.040, 0.075±0.035, 0.067±0.063, and 0.073±0.065 mg L-1 respectively. Overall, the MIC of boscalid was 1 mg L-1, and the mean MIC was 0.111±0.044 mg L-1. The ED50 values of representative isolates are also presented, as determined by colony formation with dispersed spore inoculation on a medium amended with fungicides. The results show that the benzimidazoles are ineffective against S. pyricola isolates in Greece and suggest that the future effectiveness of the DMIs is at risk.

  19. Annual Fungicide Loadings

    Data.gov (United States)

    U.S. Environmental Protection Agency — Pesticides, Herbicides, Fungicides...etc, are used for a variety of purposes, including control of household, lawn, and garden pests; for control of mosquitoes and...

  20. Observations on the Behaviour of Different Populations of Plasmopara viticola Resistant to QoI Fungicides in Italian Vineyards

    Directory of Open Access Journals (Sweden)

    M.L. Gullino

    2004-12-01

    Full Text Available Grapevine downy mildew, caused by Plasmopara viticola, is probably the most damaging fungal disease of grapevine world-wide. Among the fungicides recently developed for downy mildew control is the QoI class of fungicides, which inhibits mitochondrial respiration. Since 1999, selected P. viticola populations in northern Italy have been monitored for resistance to QoI fungicides. Detached leaf discs and whole potted plants were used under controlled conditions to test the sampled populations. QoI-resistant populations of P. viticola were found in all the vineyards sampled in 2001 and 2002 in Trentino Alto Adige and Friuli Venezia Giulia, where failure in QoI control was reported. Many of the populations had minimum inhibition concentration (MIC values 3– 30 times higher than those of sensitive reference populations. Populations of P. viticola sampled from vineyards in Piedmont, where no QoI fungicides had previously been used, showed MIC values equal to, or lower than those of the reference populations. Most of the P. viticola populations collected in Trentino Alto Adige in 2001 showed high virulence in leaf disc test and were not controlled by QoI fungicides, applied both at field and double field rates in the whole plant test. Most of these populations retained their virulence in the subsequent leaf disc test in water.

  1. Minimum effective concentration of bupivacaine for axillary brachial plexus block guided by ultrasound

    Directory of Open Access Journals (Sweden)

    Alexandre Takeda

    2015-05-01

    Full Text Available Introduction: The use of ultrasound in regional anesthesia allows reducing the dose of local anesthetic used for peripheral nerve block. The present study was performed to determine the minimum effective concentration (MEC90 of bupivacaine for axillary brachial plexus block. Methods: Patients undergoing hand surgery were recruited. To estimate the MEC90, a sequential up-down biased coin method of allocation was used. The bupivacaine dose was 5 mL for each nerve (radial, ulnar, median, and musculocutaneous. The initial concentration was 0.35%. This concentration was changed by 0.05% depending on the previous block; a blockade failure resulted in increased concentration for the next patient; in case of success, the next patient could receive or reduction (0.1 probability or the same concentration (0.9 probability. Surgical anesthesia was defined as driving force ≤2 according to the modified Bromage scale, lack of thermal sensitivity and response to pinprick. Postoperative analgesia was assessed in the recovery room with numeric pain scale and the amount of drugs used within 4 h after the blockade. Results: MEC90 was 0.241% [R2: 0.978, confidence interval: 0.20–0.34%]. No patient, with successful block, reported pain after 4 h. Conclusion: This study demonstrated that ultrasound guided axillary brachial plexus block can be performed with the use of low concentration of local anesthetics, increasing the safety of the procedure. Further studies should be conducted to assess blockade duration at low concentrations. Resumo: Introdução: O uso do ultrassom na anestesia regional permite a redução da dose de anestésico local utilizada para o bloqueio de nervos periféricos. O presente estudo foi conduzido com o objetivo de determinar a concentração mínima efetiva (CME90 de bupivacaína para o bloqueio do plexo braquial via axilar (BPVA. Métodos: Pacientes submetidos a cirurgias da mão foram recrutados. Foi usado um método de alocação

  2. Isoflurane minimum alveolar concentration sparing effects of fentanyl in the dog.

    Science.gov (United States)

    Williamson, Allan J; Soares, Joao H N; Pavlisko, Noah D; McAlister Council-Troche, Robert; Henao-Guerrero, Natalia

    2017-07-01

    To characterize the isoflurane-sparing effects of a high and a low dose of fentanyl in dogs, and its effects on mean arterial pressure (MAP) and heart rate (HR). Prospective, randomized crossover trial. Eight healthy male Beagle dogs weighing 12.1 ± 1.6 kg [mean ± standard deviation (SD)] and approximate age 1 year. Dogs were anesthetized using isoflurane and minimum alveolar concentration (MAC) was determined in duplicate by the bracketing method using an electrical stimulus on the tarsus. Animals were administered fentanyl: low dose (33 μg kg -1 loading dose, 0.2 μg kg -1  minute -1 ) or high dose (102 μg kg -1 loading dose, 0.8 μg kg -1  minute -1 ) and MAC was re-determined (MAC ISO-F ). Blood was collected for analysis of plasma fentanyl concentrations before administration and after MAC ISO-F determination. All values are presented as mean ± SD. Isoflurane MAC (MAC ISO ) was 1.30 ± 0.23% in the low dose treatment, which significantly decreased to 0.75 ± 0.22% (average MAC reduction 42.3 ± 9.4%). MAC ISO was 1.30 ± 0.18% in the high dose treatment, which significantly decreased to 0.30 ± 0.11% (average MAC reduction 76.9 ± 7.4%). Mean fentanyl plasma concentrations were 6.2 and 29.5 ng mL -1 for low and high dose treatments, respectively. MAP increased significantly only in the high dose treatment (from 81 ± 8 to 92 ± 9 mmHg). HR decreased significantly in both treatments from 108 ± 25 to 61 ± 14 beats minute -1 with the low dose and from 95 ± 14 to 42 ± 4 beats minute -1 with the high dose. Fentanyl administration resulted in a dose-dependent isoflurane MAC-sparing effect with bradycardia at both doses and an increase in MAP only at high dose. Further evaluation is needed to determine the effects of fentanyl on the overall cardiovascular function. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All

  3. Study on the Antimicrobial activity and Minimum Inhibitory Concentration of Essential Oils of Spices

    Directory of Open Access Journals (Sweden)

    R.V.N.Srujan and M.Sravanthi

    Full Text Available Antibacterial activity and minimum inhibitory concentration (MIC of essential oils of garlic, clove and cinnamon were estimated by using various bacterial pathogens. Among the bacterial pathogens tested against essential oil of garlic, Staphylococcus aureus was found to be highly sensitive followed by E.coli. L.monocytogenes and S.pyogenes were found to be less sensitive. The essential oil of clove was found to be most active against S.aureus followed by E.coli. B.cereus and C. jejuni. The essential oil of cinnamon was also most active against S.aureus followed by E.coli and C.jejuni. Essential oil of cinnamon was found to be active against all the bacterial pathogens tested, when compared to garlic and clove oils. However Staph. aureus, E. coli and C.jejuni were found to be most sensitive to the action of essential oils of garlic, clove and cinnamon. Among the bacterial pathogens tested against essential oils of spices to know the MIC by agar diffusion method, C.jejuni was found to be most sensitive to the essential oil of garlic followed by E.coli, S. typhimurium and Staphylococcus aureus. L. monocytogenes and Methicillin resistant Staph. aureus were found to be comparatively less sensitive. Essential oil of clove was also found to be highly effective against C.jejuni followed by E.coli, S.typhimurium and S.aureus. Again L.monocytogenes and Methicillin resistant S.aureus were comparatively less sensitive to the action of essential oil of clove. All most all the bacterial pathogens tested were found to be sensitive to the essential oil of cinnamon. However C.jejuni and E.coli were found to be most sensitive followed by S.typhimurium, Staph. aureus and Methicillin resistant Staph. aureus . [Vet. World 2011; 4(7.000: 311-316

  4. A self-loading microfluidic device for determining the minimum inhibitory concentration of antibiotics.

    Science.gov (United States)

    Cira, Nate J; Ho, Jack Y; Dueck, Megan E; Weibel, Douglas B

    2012-03-21

    This article describes a portable microfluidic technology for determining the minimum inhibitory concentration (MIC) of antibiotics against bacteria. The microfluidic platform consists of a set of chambers molded in poly(dimethylsiloxane) (PDMS) that are preloaded with antibiotic, dried, and reversibly sealed to a second layer of PDMS containing channels that connect the chambers. The assembled device is degassed via vacuum prior to its use, and the absorption of gas by PDMS provides the mechanism for actuating and metering the flow of fluid in the microfluidic channels and chambers. During the operation of the device, degas driven flow introduces a suspension of bacterial cells, dissolves the antibiotic, and isolates cells in individual chambers without cross contamination. The growth of bacteria in the chambers in the presence of a pH indicator produces a colorimetric change that can be detected visually using ambient light. Using this device we measured the MIC of vancomycin, tetracycline, and kanamycin against Enterococcus faecalis 1131, Proteus mirabilis HI4320, Klebsiella pneumoniae, and Escherichia coli MG1655 and report values that are comparable to standard liquid broth dilution measurements. The device provides a simple method for MIC determination of individual antibiotics against human pathogens that will have applications for clinical and point-of-care medicine. Importantly, this device is designed around simplicity: it requires a single pipetting step to introduce the sample, no additional components or external equipment for its operation, and provides a straightforward visual measurement of cell growth. As the device introduces a novel approach for filling and isolating dead-end microfluidic chambers that does not require valves and actuators, this technology should find applications in other portable assays and devices.

  5. Effect of gamma radiation on ''in vitro''' efficiency of fungicides

    International Nuclear Information System (INIS)

    Menten, J.O.M.; Oliveira, G.C.X.

    1984-01-01

    The activity of 60 Co gamma radiation on eight fungicides used in post-harvesting treatment of agricultural products, was studied. Rhizoctonia solani was used in biological test as indicator-fungus. The fungicides were submitted to gamma radiation doses of O (control), 1, 10, 100, 1000 and 10.000 kR, samples of the fungicides were added to the PSA culture media to obtain 0, 1, 10 and 100 ppm concentrations of the active component of each product and of each radiation dose. The ED 50 (concentration of fungicide necessary to cause 50% radial reduction of the fungic mycelium) of each fungicide in the different gamma radiation doses was determined. (M.A.C.) [pt

  6. Influence of vancomycin minimum inhibitory concentration on the treatment of methicillin-resistant Staphylococcus aureus bacteremia.

    Science.gov (United States)

    Soriano, Alex; Marco, Francesc; Martínez, José A; Pisos, Elena; Almela, Manel; Dimova, Veselka P; Alamo, Dolores; Ortega, Mar; Lopez, Josefina; Mensa, Josep

    2008-01-15

    Vancomycin treatment failure in methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is not uncommon, even when MRSA is susceptible to vancomycin. The aim of our study was to evaluate whether vancomycin minimum inhibitory concentration has any influence on the mortality associated with MRSA bacteremia. A total of 414 episodes of MRSA bacteremia were prospectively followed-up from 1991 through 2005. MIC of vancomycin for the first isolate was determined by E-test. Clinical variables recorded were age, comorbidity, prior administration of vancomycin, use of corticosteroids, prognosis of underlying disease, source of bacteremia, the need for mechanical ventilation, shock, and mortality. A "treatment group" variable was created and defined as follows: (1) receipt of empirical vancomycin and an isolate with a vancomycin MIC of 1 microg/mL (38 episodes), (2) receipt of empirical vancomycin and an isolate with a vancomycin MIC of 1.5 microg/mL (90 episodes), (3) receipt of empirical vancomycin and an isolate with a vancomycin MIC of 2 microg/mL (40 episodes), and (4) receipt of inappropriate empirical therapy (246 episodes). Univariate and multivariate analyses were performed. Episodes caused by strains with a vancomycin MIC of 2 microg/mL were independently associated with a lower risk of shock (odds ratio [OR], 0.33; 95% confidence interval [CI], 0.15-0.75). Multivariate analysis selected receipt of empirical vancomycin and an isolate with a vancomycin MIC of 2 microg/mL (OR, 6.39; 95% CI, 1.68-24.3), receipt of inappropriate empirical therapy (OR, 3.62; 95% CI, 1.20-10.9), increasing age (OR, 1.02; 95% CI, 1.00-1.04), use of corticosteroids (OR, 1.85; 95% CI, 1.04-3.29), an ultimately (OR, 10.2; 95% CI, 2.85-36.8) or rapidly (OR, 1.81; 95% CI, 1.06-3.10) fatal underlying disease, high-risk (OR, 3.60; 95% CI, 1.89-6.88) and intermediate-risk (OR, 2.18; 95% CI, 1.17-4.04) sources of bacteremia, and shock (OR, 7.38; 95% CI, 4.11-13.3) as the best predictors of

  7. Resazurin-based 96-well plate microdilution method for the determination of minimum inhibitory concentration of biosurfactants.

    Science.gov (United States)

    Elshikh, Mohamed; Ahmed, Syed; Funston, Scott; Dunlop, Paul; McGaw, Mark; Marchant, Roger; Banat, Ibrahim M

    2016-06-01

    To develop and validate a microdilution method for measuring the minimum inhibitory concentration (MIC) of biosurfactants. A standardized microdilution method including resazurin dye has been developed for measuring the MIC of biosurfactants and its validity was established through the replication of tetracycline and gentamicin MIC determination with standard bacterial strains. This new method allows the generation of accurate MIC measurements, whilst overcoming critical issues related to colour and solubility which may interfere with growth measurements for many types of biosurfactant extracts.

  8. In situ quantification of ultra-low O2 concentrations in oxygen minimum zones

    DEFF Research Database (Denmark)

    Larsen, Morten; Lehner, Philipp; Borisov, Sergey M.

    2016-01-01

    based on the palladium(II)-benzoporphyrin luminophore, immobilized in a perfluorinated matrix with high O2 permeability. The trace sensor has a detection limit of ∼5 nmol L−1 with a dynamic range extending up to ∼2 μmol L−1. The sensor demonstrates a response time ..., and fully reversible response to hydrostatic pressure and temperature. The sensor showed excellent stability for continuously measurements during depth profiling in Oxygen Minimum Zones (OMZ). The novel sensor was deployed in situ using a Trace Oxygen Profiler instrument (TOP) equipped with two additional O...

  9. Triazole Fungicides Sensitivity of Sclerotinia homoeocarpa in Korean Golf Courses

    Directory of Open Access Journals (Sweden)

    Ji Won Lee

    2017-12-01

    Full Text Available Chemical management of dollar spot in turf may lead to the development of Sclerotinia homoeocarpa populations with reduced fungicide sensitivity. The objective of this study was to investigate resistance of S. homoeocarpa isolates to triazole fungicides and to test cross-resistance among three triazole fungicides. A total of 66 isolates of S. homoeocarpa were collected from 15 golf courses across Korea, and tested via in vitro sensitivity assay against hexaconazole, propiconazole and tebuconazole. EC₅₀ values of the isolates to these fungicides were distributed in the range of 0.001–1.1 a. i. μg ml−1. Based on the EC₅₀ values, twelve representative strains were selected as sensitive isolates including control and insensitive isolates with respect to each fungicide. At a concentration of 0.1 a. i. μg ml−1 for all fungicides, the selected strains were distinguished as sensitive or resistant isolates with the mycelial growth inhibition rate of 50% as the criterion. The EC₅₀ values of resistant strains exposed to hexaconazole, propiconazole and tebuconazole were 20–50 times, 50–70 times, and 77 times greater, respectively, than that of the control strains. Two isolates of S. homoeocarpa S0–41 and Sh14-2-1 showed sensitivity toward all the fungicides used, while two other isolates Sh7-5-1 and Sh2-1-1 showed resistance to all fungicides. Each isolate showed similar resistance to the three types of triazole fungicides, whereby cross-resistance of isolates was confirmed in the present study; all three triazole fungicide combinations displayed significant correlation coefficients equivalent to or greater than 0.8.

  10. Occurrence of azoxystrobin, propiconazole, and selected other fungicides in US streams, 2005-2006

    Science.gov (United States)

    Battaglin, William A.; Sandstrom, Mark W.; Kuivila, Kathryn; Kolpin, Dana W.; Meyer, Michael T.

    2011-01-01

    Fungicides are used to prevent foliar diseases on a wide range of vegetable, field, fruit, and ornamental crops. They are generally more effective as protective rather than curative treatments, and hence tend to be applied before infections take place. Less than 1% of US soybeans were treated with a fungicide in 2002 but by 2006, 4% were treated. Like other pesticides, fungicides can move-off of fields after application and subsequently contaminate surface water, groundwater, and associated sediments. Due to the constant pressure from fungal diseases such as the recent Asian soybean rust outbreak, and the always-present desire to increase crop yields, there is the potential for a significant increase in the amount of fungicides used on US farms. Increased fungicide use could lead to increased environmental concentrations of these compounds. This study documents the occurrence of fungicides in select US streams soon after the first documentation of soybean rust in the US and prior to the corresponding increase in fungicide use to treat this problem. Water samples were collected from 29 streams in 13 states in 2005 and/or 2006, and analyzed for 12 target fungicides. Nine of the 12 fungicides were detected in at least one stream sample and at least one fungicide was detected in 20 of 29 streams. At least one fungicide was detected in 56% of the 103 samples, as many as five fungicides were detected in an individual sample, and mixtures of fungicides were common. Azoxystrobin was detected most frequently (45% of 103 samples) followed by metalaxyl (27%), propiconazole (17%), myclobutanil (9%), and tebuconazole (6%). Fungicide detections ranged from 0.002 to 1.15 μ/L. There was indication of a seasonal pattern to fungicide occurrence, with detections more common and concentrations higher in late summer and early fall than in spring. At a few sites, fungicides were detected in all samples collected suggesting the potential for season-long occurrence in some streams

  11. A long term field study of the effect of fungicides penconazole and sulfur on yeasts in the vineyard.

    Science.gov (United States)

    Cordero-Bueso, Gustavo; Arroyo, Teresa; Valero, Eva

    2014-10-17

    This research deals with how two fungicide treatments against powdery mildew, penconazole as a systematic fungicide and sulfur as an inorganic broad-spectrum fungicide, affect the diversity and density of wine yeasts associated with grape berry surfaces and subsequent spontaneous fermentations. Unlike other studies in this area, this work aims to evaluate this effect on the population dynamics in the environment, the conditions of which are not reproducible in the laboratory. A long term (three year) sampling plan was thus devised. A minimum inhibitory concentration assay was also carried out in the laboratory in order to prove the influence of these antifungals on yeast populations. While both antifungal treatments (penconazole and sulfur) were similarly effective against powdery mildew, each had a very different effect on yeast populations. Penconazole showed the most negative effect on biodiversity in the vineyard and was the fungicide to which the isolated yeasts showed the greatest sensitivity. This study therefore evidences the suitability of treatment with sulfur, in both conventional and organic viticulture, to preserve the yeast population associated with grape berries, in particular the Saccharomyces cerevisiae species. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Biochemical changes induced by fungicides in nitrogen fixing Nostoc sp.

    Science.gov (United States)

    Deviram, G V N S; Pant, Gaurav; Prasuna, R Gyana

    2013-01-01

    The present study indicates the effect of fungicides (approved by WHO) and their behavior on nitrogen fixer of rice eco system Nostoc sp. Application of plant protecting chemicals at recommended levels braced up the growth of blue green algae thereby enhancing heterocyst formation and nitrogenase activity. Nostoc sp demoed varying degrees of sensitivity to fungicides. Biomass yield, protein, carbohydrate content reduced after 3pg/mL concentration. Heterocyst damage was observed from 4μg/mL, Proline content increased with increase in fungicide concentration, utmost yellowing of the culture started from 4μg/mL. The decreasing order of the toxicity to Nostoc sp with fungicides was Mancozeb> Ediphenphos> Carbendazim> Hexaconazole.

  13. The minimum alveolar concentration of sevoflurane in ring-tailed lemurs (Lemur catta) and aye-ayes (Daubentonia madagascariensis).

    Science.gov (United States)

    Chinnadurai, Sathya K; Williams, Cathy

    2016-01-01

    To determine the minimum alveolar concentration (MAC) of sevoflurane for ring-tailed lemurs (Lemur catta) and aye-ayes (Daubentonia madagascariensis). Prospective experimental trial. Six adult ring-tailed lemurs, aged 1.3-11.2 years (median age: 8.26) and weighing a mean ± standard deviation (SD) of 2283 ± 254 g. Five adult aye-ayes, aged 4.4-19.3 years (median age: 8.0) and weighing 2712 ± 191 g. Minimum alveolar concentration of sevoflurane was determined using a tail-clamp stimulus. The end-tidal sevoflurane (Fe'Sevo) concentration was increased or decreased by approximately 10% after a positive or negative response to tail clamping, respectively. This procedure was repeated until a positive and negative result were seen on two consecutive trials (i.e. a negative result was achieved and a single 10% decrease in Fe'Sevo concentration resulted in a positive test). The MAC for that animal was determined to be the mean of the concentrations at the two consecutive trials. The mean ± SD MAC of sevoflurane for ring-tailed lemurs was 3.48 ± 0.55% and 1.84 ± 0.17 for aye-ayes. This represents a 47.1% higher MAC in ring-tailed lemurs compared to aye-ayes. The sevoflurane MAC was significantly higher in ring-tailed lemurs, compared to aye-ayes. The MAC of sevoflurane in aye-ayes is consistent with reported MAC values in other species. Extrapolation of sevoflurane anesthetic dose between different species of lemurs could lead to significant errors in anesthetic dosing. © 2015 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia.

  14. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers

    International Nuclear Information System (INIS)

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-01-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr_3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV. - Highlights: • A small-sized UAV airborne sensor system was developed. • Three radioactive models were chosen to simulate the Fukushima accident. • Both the air and ground radiation were considered in the models. • The efficiency calculations and MDAC values were given. • The sensor system is able to monitor in serious nuclear accidents.

  15. Efficiency calibration and minimum detectable activity concentration of a real-time UAV airborne sensor system with two gamma spectrometers.

    Science.gov (United States)

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-04-01

    A small-sized UAV (NH-UAV) airborne system with two gamma spectrometers (LaBr3 detector and HPGe detector) was developed to monitor activity concentration in serious nuclear accidents, such as the Fukushima nuclear accident. The efficiency calibration and determination of minimum detectable activity concentration (MDAC) of the specific system were studied by MC simulations at different flight altitudes, different horizontal distances from the detection position to the source term center and different source term sizes. Both air and ground radiation were considered in the models. The results obtained may provide instructive suggestions for in-situ radioactivity measurements of NH-UAV. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. The determination of minimum inhibitory concentrations of selected antimicrobials for porcine Haemophilus parasuis isolates from the Czech Republic

    Directory of Open Access Journals (Sweden)

    Kateřina Nedbalcová

    2017-01-01

    Full Text Available Haemophilus parasuis isolates obtained from pigs in the Czech Republic were tested for their susceptibility to amoxicillin, penicillin, ceftiofur, enrofloxacin, tetracycline, and tulathromycin by determination of minimum inhibitory concentrations using the broth microdilution method. The H. parasuis isolates were mostly susceptible to majority of tested antimicrobials (amoxicillin 90%, penicillin 73.3%, enrofloxacin 83.3%, and tulathromycin 83.3%. All isolates were susceptible to ceftiofur. On the other hand, no isolate was susceptible to tetracycline, 30% of tested isolates were intermediately susceptible, and 70% were resistant. These findings indicate that tested antimicrobials with the exception of tetracycline should be the preferred option used for the treatment of infection caused by H. parasuis but due to the potential transmission of resistance from animals to humans, the use of ceftiofur is considered as a last resort option in antimicrobial treatment of animals.

  17. Nucleic adaptability of heterokaryons to fungicides in a multinucleate fungus, Sclerotinia homoeocarpa.

    Science.gov (United States)

    Kessler, Dylan; Sang, Hyunkyu; Bousquet, Amanda; Hulvey, Jonathan P; Garcia, Dawlyn; Rhee, Siyeon; Hoshino, Yoichiro; Yamada, Toshihiko; Jung, Geunhwa

    2018-06-01

    Sclerotinia homoeocarpa is the causal organism of dollar spot in turfgrasses and is a multinucleate fungus with a history of resistance to multiple fungicide classes. Heterokaryosis gives rise to the coexistence of genetically distinct nuclei within a cell, which contributes to genotypic and phenotypic plasticity in multinucleate fungi. We demonstrate that field isolates, resistant to either a demethylation inhibitor or methyl benzimidazole carbamate fungicide, can form heterokaryons with resistance to each fungicide and adaptability to serial combinations of different fungicide concentrations. Field isolates and putative heterokaryons were assayed on fungicide-amended media for in vitro sensitivity. Shifts in fungicide sensitivity and microsatellite genotypes indicated that heterokaryons could adapt to changes in fungicide pressure. Presence of both nuclei in heterokaryons was confirmed by detection of a single nucleotide polymorphism in the β-tubulin gene, the presence of microsatellite alleles of both field isolates, and the live-cell imaging of two different fluorescently tagged nuclei using laser scanning confocal microscopy. Nucleic adaptability of heterokaryons to fungicides was strongly supported by the visualization of changes in fluorescently labeled nuclei to fungicide pressure. Results from this study suggest that heterokaryosis is a mechanism by which the pathogen adapts to multiple fungicide pressures in the field. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. In vivo sensitivity of Phakopsora pachyrhizi to DMI and QoI fungicides

    Directory of Open Access Journals (Sweden)

    Erlei Melo Reis

    2015-03-01

    Full Text Available In in vivo experiments the sensitivity of 18 isolates of Phakopsora pachyrhizi from several regions of Brazil to IDM fungicides (cyproconazole, epoxiconazole and tebuconazole and an IQE (pyraclostrobin were evaluated. The assessments were based on leaflet uredia density. Inhibitory concentration (IC50 and sensitivity reduction factor were determined for all fungicide x strain interactions. Tebuconazole sensitivity reduction was detected for most fungus isolates. In contrast, there was no fungicide shift in sensitivity of the fungus to pyraclostrobin. We conclude that the control failure of soybean rust found in some farms is due to the reduced sensitivity of the fungus to the IDM fungicide and that it remains sensitive to pyraclostrobin.

  19. Effects of Oral Exposure to Fungicides on Honey Bee Nutrition and Virus Levels.

    Science.gov (United States)

    Degrandi-Hoffman, Gloria; Chen, Yanping; Watkins Dejong, Emily; Chambers, Mona L; Hidalgo, Geoffrey

    2015-12-01

    Sublethal exposure to fungicides can affect honey bees (Apis mellifera L.) in ways that resemble malnutrition. These include reduced brood rearing, queen loss, and increased pathogen levels. We examined the effects of oral exposure to the fungicides boscalid and pyraclostrobin on factors affecting colony nutrition and immune function including pollen consumption, protein digestion, hemolymph protein titers, and changes in virus levels. Because the fungicides are respiratory inhibitors, we also measured ATP concentrations in flight muscle. The effects were evaluated in 3- and 7-d-old worker bees at high fungicide concentrations in cage studies, and at field-relevant concentrations in colony studies. Though fungicide levels differed greatly between the cage and colony studies, similar effects were observed. Hemolymph protein concentrations were comparable between bees feeding on pollen with and without added fungicides. However, in both cage and colony studies, bees consumed less pollen containing fungicides and digested less of the protein. Bees fed fungicide-treated pollen also had lower ATP concentrations and higher virus titers. The combination of effects we detected could produce symptoms that are similar to those from poor nutrition and weaken colonies making them more vulnerable to loss from additional stressors such as parasites and pathogens. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

  20. Spatial and temporal distribution of fungicides applied to creeping bentgrass.

    Science.gov (United States)

    Hockemeyer, Kurt R; Latin, Richard

    2015-05-01

    Turf managers often rely on fungicides to limit damage caused by root diseases. Because fungicides are applied to aboveground surfaces and do not move basipetally, they are effective against root pathogens only when fungitoxic concentrations migrate to the rhizosphere. This research focused on the distribution of modern fungicides in verdure, thatch, sand, and roots of creeping bentgrass [ L. var. (Huds.) Farw.] maintained as a putting green. The fungicides azoxystrobin (methyl (E)-2-[2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl]-3-methoxyacrylate), propiconazole (1,2,4-triazole, 1-((2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl)methyl), pyraclostrobin (carbamic acid, [2-[[[1-(4-chlorophenyl)-1H-pyrazol-3-yl]oxy]methyl]phenyl]methoxy-,methyl ester), and thiophanate-methyl (dimethyl 4,'4-o-phenylenebis[3-thioallophanate]) were applied to replicate field plots in a water volume of 815 L ha. Plots were sampled at 0, 3, 7, 10, 14, 17, and 21 d after application by extracting cores measuring 1.9 cm in diameter by 3.8 cm deep. Cores were separated into verdure/thatch, sand, and roots before quantitative determination (liquid chromatography, triple quadrupole mass spectrometry) of fungicide residues. Fungicide residues in verdure/thatch declined steadily with time and support previously reported results describing fungicide depletion. Fungicides were detected in roots and sand within 5 h of application at very low (1-15 mg kg) concentrations and remained at low levels throughout the sampling period. Fungicides differed with respect to amounts recovered per turfgrass component. Azoxystrobin and propiconazole were associated with roots for the duration of the experiment, but pyraclostrobin was nearly undetectable. Near-zero levels of all fungicides were detected in the sand component. Half-life values in the verdure/thatch component ranged from 2.3 to 18.9 d. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of

  1. The effect of sub-minimum inhibitory concentration of ciprofloxacin concentrations on enteroaggregative Escherichia coli and the role of the surface protein dispersin

    Energy Technology Data Exchange (ETDEWEB)

    Mortensen, Ninell P [ORNL; Fowlkes, Jason Davidson [ORNL; Trevino-Dopatka, Sonia [ORNL; Maggart, Michael J [ORNL; Boisen, Nadia [University of Virginia School of Medicine; Doktycz, Mitchel John [ORNL; Nataro, James [University of Virginia School of Medicine; Allison, David P [ORNL

    2011-01-01

    Enteroaggregative Escherichia coli (EAEC) are bacterial pathogens that cause watery diarrhea, which is often persistent and can be inflammatory. The antibiotic ciprofloxacin is used to treat EAEC infections, but a full understanding of the antimicrobial effects of ciprofloxacin is needed for more efficient treatment of bacterial infections. In this study, it was found that sub-minimum inhibitory concentrations (sub-MICs) of ciprofloxacin had an inhibitory effect on EAEC adhesion to glass and mammalian HEp-2 cells. It was also observed that bacterial surface properties play an important role in bacterial sensitivity to ciprofloxacin. In an EAEC mutant strain where the hydrophobic positively charged surface protein dispersin was absent, sensitivity to ciprofloxacin was reduced compared with the wild-type strain. Identified here are several antimicrobial effects of ciprofloxacin at sub-MIC concentrations indicating that bacterial surface hydrophobicity affects the response to ciprofloxacin. Investigating the effects of sub-MIC doses of antibiotics on targeted bacteria could help to further our understanding of bacterial pathogenicity and elucidate future antibiotic treatment modalities.

  2. Chronic aquatic effect assessment for the fungicide azoxystrobin

    NARCIS (Netherlands)

    Wijngaarden, van R.P.A.; Belgers, J.D.M.; Zafar, M.I.; Matser, A.M.; Boerwinkel, M.C.; Arts, G.H.P.

    2014-01-01

    This study examined ecological effects of a range of chronic exposure concentrations of the fungicide azoxystrobin in freshwater experimental systems (1270 L outdoor microcosms). Intended and environmentally relevant test concentrations of azoxystrobin were 0, 0.33, 1, 3.3, 10, 33 µg ai/L, kept at

  3. The effect of using a fungicide along with bactericide in the main ...

    African Journals Online (AJOL)

    quarternized compounds), and a fungicide (2-thiocyanomethylthio benzothiazole based) commonly used in Turkish leather industry were chosen. The bactericides were added into the main soaking float with and without different concentrations of fungicide. In each trial, liquor samples were taken at the end of the main ...

  4. Determination of the minimum inhibitory concentration (MIC and mutant prevention concentration (MPC of selected antimicrobials in bovine and swine Pasteurella multocida, Escherichia coli, and Staphylococcus aureus isolates

    Directory of Open Access Journals (Sweden)

    Kateřina Nedbalcová

    2015-01-01

    Full Text Available We compared the values of the minimum inhibitory concentration (MIC and mutant prevention concentration (MPC values ​​of three antimicrobial agents for 72 bovine isolates of Pasteurella multocida, 80 swine isolates of P. multocida, 80 bovine isolates of Escherichia coli, 80 swine isolates of E. coli, and 80 isolates of Staphylococcus aureus from bovine mastitis. The ratio of MIC90​​/MPC90 which limited mutant selection window (MSW was ≤ 0.12/4 mg/l for enrofloxacin, 0.5/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in bovine P. multocida isolates, ≤ 0.12/2 mg/l for enrofloxacin, 0.5/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in swine P. multocida isolates, 1/16 mg/l for enrofloxacin, 8/≥ 64 mg/l for florfenicol and 8/≥ 128 mg/l for tulathromycin in bovine E. coli isolates, 0.5/16 mg/l for enrofloxacin, ≥ 64/≥ 64 mg/l for florfenicol and 8/≥ 128 mg/l for tulathromycin in swine E. coli isolates, and 0.25/16 mg/l for enrofloxacin, 4/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in S. aureus isolates. These findings indicate that the dosage of antimicrobial agents to achieve serum concentration equal to or higher than MPC could reduce selection of resistant bacterial subpopulation.

  5. Effects of carprofen and meloxicam with or without butorphanol on the minimum alveolar concentration of sevoflurane in dogs.

    Science.gov (United States)

    Yamashita, Kazuto; Okano, Yoshihiko; Yamashita, Maiko; Umar, Mohammed A; Kushiro, Tokiko; Muir, William W

    2008-01-01

    Sparing effects of carprofen and meloxicam with or without butorphanol on the minimum alveolar concentration (MAC) of sevoflurane were determined in 6 dogs. Anesthesia was induced and maintained with sevoflurane in oxygen, and MAC was determined by use of a tail clamp method. The dogs were administered a subcutaneous injection of carprofen (4 mg/kg) or meloxicam (0.2 mg/kg), or no medication (control) one hour prior to induction of anesthesia. Following the initial determination of MAC, butorphanol (0.3 mg/kg) was administered intramuscularly, and MAC was determined again. The sevoflurane MACs for carprofen alone (2.10 +/- 0.26%) and meloxicam alone (2.06 +/- 0.20%) were significantly less than the control (2.39 +/- 0.26%). The sevoflurane MACs for the combination of carprofen with butorphanol (1.78 +/- 0.20%) and meloxicam with butorphanol (1.66 +/- 0.29%) were also significantly less than the control value after the administration of butorphanol (2.12 +/- 0.28%). The sevoflurane sparing effects of the combinations of carprofen with butorphanol and meloxicam with butorphanol were additive.

  6. Minimum bactericidal concentration of phenols extracted from oil vegetation water on spoilers, starters and food-borne bacteria

    Directory of Open Access Journals (Sweden)

    Luca Fasolato

    2015-05-01

    Full Text Available The aim of the study was to assess the in vitro effect of phenols extracted from oil vegetation water (PEOW on several food-borne strains. Antibacterial activity of PEOW was based on the minimum bactericidal concentration (MBC on microtitre assay. The taxa tested were: Staphylococcus (n. 5, Listeria (n. 4, Escherichia (n. 2, Salmonella (n. 1, Pseudomonas (n. 3, Lactobacillus (n. 2 and Pediococcus (n. 1. S. aureus and L. monocytogens showed the lowest level of resistance to PEOW (MBC=1.5-3 mg/mL. In contrast, the Gram negative strains (e.g. S. Typhimurium and Pseudomonas spp. were in some cases unaffected by the tested doses and the MBCs ranged between 6 to 12 mg/mL. Starter cultures were dramatically reduced on growth (e.g. Staphylococcus xylosus; 0.75 mg/mL MBC. The thresholds for pathogenic strains could be considered for further applications of PEOW in food models (e.g. shelf life or challenge test studies.

  7. Minimum inhibitory concentration of the plant extracts′ combinations against dental caries and plaque microorganisms: An in vitro study

    Directory of Open Access Journals (Sweden)

    B R Chandra Shekar

    2016-01-01

    Full Text Available Introduction: Oral health status has witnessed marked advances in many industrialized countries. However, dental caries is consistently increasing in developing countries, and periodontal diseases are among most common afflictions to humankind. Approach best suited for developing countries is to focus on the prevention with innovative strategies. Hence, evolution of novel, innovative strategies to prevent dental caries and periodontal diseases is need of hour. Objective: To determine minimum inhibitory concentration (MIC of combinations of Acacia nilotica, Murraya koenigii L. Sprengel, Eucalyptus hybrid, and Psidium guajava against dental caries and plaque microorganisms and to qualitatively identify various phytochemical constituents in individual plant extracts and their quadruple combinations. Materials and Methods: MIC of the combinations of A. nilotica, M. koenigii L. Sprengel, Eucalyptus hybrid, and P. guajava on Streptococcus mutans, Lactobacillus acidophilus (dental caries bacteria, Streptococcus sanguis, Streptococcus salivarius (primary plaque colonizers, Fusobacterium nucleatum (secondary plaque colonizer, and Porphyromonas gingivalis (tertiary plaque colonizer was determined using broth dilution method. Series of dilutions of quadruple combinations ranging from 0.05% to 1.5% were prepared. 100 μL of each serial dilution of quadruple combinations was added to each tube containing bacterial culture. The optical density was noted after incubation in each tube to estimate the MIC for each bacterium. Results: MIC of the polyherbal combinations on S. mutans, S. sanguis, S. salivarius, L. acidophilus, F. nucleatum, and P. gingivalis was found to be 0.25%, 0.05%, 0.05%, 0.1%, 0.25%, and 0.25%, respectively. Conclusion: The quadruple combinations of these four plant extracts could be considered in the evolution of an indigenous polyherbal mouth rinse as the formulation inhibited all the bacteria tested in the present study at low

  8. Effects of constant rate infusions of dexmedetomidine or MK-467 on the minimum alveolar concentration of sevoflurane in dogs.

    Science.gov (United States)

    Hector, Rachel C; Rezende, Marlis L; Mama, Khursheed R; Steffey, Eugene P; Knych, Heather K; Hess, Ann M; Honkavaara, Juhana M; Raekallio, Marja R; Vainio, Outi M

    2017-07-01

    To determine the effects of low and high dose infusions of dexmedetomidine and a peripheral α 2 -adrenoceptor antagonist, MK-467, on sevoflurane minimum alveolar concentration (MAC) in dogs. Crossover experimental study. Six healthy, adult Beagle dogs weighing 12.6±0.9 kg (mean±standard deviation). Dogs were anesthetized with sevoflurane in oxygen. After a 60-minute instrumentation and equilibration period, the MAC of sevoflurane was determined in triplicate using the tail clamp technique. PaCO 2 and temperature were maintained at 40±5 mmHg (5.3±0.7 kPa) and 38±0.5 ºC, respectively. After baseline MAC determination, dogs were administered two incremental loading and infusion doses of either dexmedetomidine (1.5 μg kg -1 then 1.5 μg kg -1  hour -1 and 4.5 μg kg -1 then 4.5 μg kg -1  hour -1 ) or MK-467 (90 μg kg -1 then 90 μg kg -1  hour -1 and 180 μg kg -1 then 180 μg kg -1  hour -1 ); loading doses were administered over 10 minutes. MAC was redetermined in duplicate starting 30 minutes after the start of drug administration at each dose. End-tidal sevoflurane concentrations were corrected for calibration and adjusted to sea level. A repeated-measures analysis was performed and comparisons between doses were conducted using Tukey's method. Statistical significance was considered at pbenefits of the addition of a peripheral α 2 -adrenergic antagonist to inhalation anesthesia in dogs. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

  9. Minimum inhibitory (MIC) and minimum microbicidal concentration (MMC) of polihexanide and triclosan against antibiotic sensitive and resistant Staphylococcus aureus and Escherichia coli strains

    Science.gov (United States)

    Assadian, Ojan; Wehse, Katrin; Hübner, Nils-Olaf; Koburger, Torsten; Bagel, Simone; Jethon, Frank; Kramer, Axel

    2011-01-01

    Background: An in-vitro study was conducted investigating the antimicrobial efficacy of polihexanide and triclosan against clinical isolates and reference laboratory strains of Staphylococcus aureus and Escherichia coli. Methods: The minimal inhibitory concentration (MIC) and the minimal microbicidal concentration (MMC) were determined following DIN 58940-81 using a micro-dilution assay and a quantitative suspension test following EN 1040. Polihexanide was tested in polyethylene glycol 4000, triclosan in aqueous solutions. Results: Against all tested strains the MIC of polihexanide ranged between 1–2 µg/mL. For triclosan the MICs varied depending on strains ranging between 0.5 µg/mL for the reference strains and 64 µg/mL for two clinical isolates. A logRF >5 without and logRF >3 with 0.2% albumin burden was achieved at 0.6 µg/mL triclosan. One exception was S. aureus strain H-5-24, where a triclosan concentration of 0.6 µg/mL required 1 minute without and 10 minutes with albumin burden to achieve the same logRFs. Polihexanide achieved a logRF >5 without and logRF >3 with albumin burden at a concentration of 0.6 µg/mL within 30 sec. The exception was the North-German epidemic MRSA strain, were an application time of 5 minutes was required. Conclusion: The clinical isolates of E. coli generally showed higher MICs against triclosan, both in the micro-dilution assay as well in the quantitative suspension test than comparable reference laboratory strains. For polihexanide and triclosan strain dependant susceptibility was shown. However, both antimicrobial compounds are effective when used in concentrations common in practice. PMID:22242087

  10. Emerging resistance against different fungicides in Lasiodiplodia theobromae, the cause of mango dieback in Pakistan

    Directory of Open Access Journals (Sweden)

    Rehman ur Ateeq

    2015-01-01

    Full Text Available Dieback of mango caused by Lasiodiplodia theobromae is among several diseases responsible for low crop production in Pakistan. To further complicate the issue, resistance in L. theobromae is emerging against different fungicides. L. theobromae was isolated from diseased samples of mango plants collected from various orchards in the Multan District. The efficacy of different fungicides viz. copper oxychloride, diethofencarb, pyrachlostrobin, carbendazim, difenoconazole, mancozeb, and thiophanate-methyl was evaluated in vitro using a poison food technique. Thiophanate-methyl at all concentrations was found to be the most effective among five systemic fungicides against L. theobromae, followed by carbendazim, difenoconazole and diethofencarb. The fungicides, i.e., thiophanate-methyl, difenoconazole, carbendazim and diethofencarb showed maximum efficacy with increasing concentration. The isolates of L. theobromae showed some resistance development against the tested fungicides when compared with previous work. These investigations provide new information about chemical selection for the control of holistic disease in mango growing zones of Pakistan.

  11. Design, synthesis, and fungicidal activities of imino diacid analogs of valine amide fungicides.

    Science.gov (United States)

    Sun, Man; Yang, Hui-Hui; Tian, Lei; Li, Jian-Qiang; Zhao, Wei-Guang

    2015-12-15

    The novel imino diacid analogs of valine amides were synthesized via several steps, including the protection, amidation, deprotection, and amino alkylation of valine, with the resulting structures confirmed by (1)H and (13)C NMR and HRMS. Bioassays showed that some of these compounds exhibited good fungicidal activity. Notably, isopropyl 2-((1-((1-(3-fluorophenyl)ethyl)amino)-3-methyl-1-oxobutan-2-yl)amino)propanoate 5i displayed significant levels of control, at 50%, against Erysiphe graminis at 3.9μM as well as a level of potency very similar to the reference azoxystrobin, which gave 60% activity at this concentration. The present work demonstrates that imino diacid analogs of valine amides could be potentially useful key compounds for the development of novel fungicides against wheat powdery mildew. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. The influence of fungicides on the growth of Trichoderma asperellum.

    Science.gov (United States)

    De Schutter, B; Aerts, R; Rombouts, L

    2002-01-01

    Numbers of strains of Trichoderma asperellum are known as biological control agents of certain root pathogens of tomato (Lycopersicon esculentum). The restricted use of fungicides is sometimes useful in combination with these biological control agents. Therefore some experiments were conducted to evaluate the growth of T. asperellum in the presence of fungicides as Previcur (active substance propamocarb) and Sumico (with the active substance carbendazim and diethofencarb). The influence of these fungicides was first examined in laboratory conditions. The fungus was brought on a potato dextrose agar where the fungicides Previcur, Sumico and carbendazim were added in a concentration of 0.1x, 1x and 10x the recommended dose. The growth of T. asperellum was totally inhibited by the three Sumico and carbendazim concentrations. T. asperellum knew a small but significant decrease of growth when the 10x dose of Previcur was added. Afterwards the influence of these fungicides on the fungus was tested in field conditions in the greenhouse. The fungus was applied to the roots of the tomato plant, which was grown on a rockwool medium. Previcur and Sumico were submitted to the plants using the normal procedure. The results of the tests showed that in field conditions there was no effect of the fungicide treatment on the presence of the fungus, although the laboratory tests showed the opposite for Sumico. To explain this contradiction two other experiments were conducted to follow the migration of the Sumico after treatment. A residue analysis showed that the highest concentration of Sumico was detected in the rockwool medium, and some residues were found in the drain water and the stems. Even with a 100x recommended dose of Sumico the fungus was still present the day after the treatment.

  13. In vitro sensitivity of Fusarium graminearum isolates to fungicides

    Directory of Open Access Journals (Sweden)

    Aveline Avozani

    2014-09-01

    Full Text Available Head blight of wheat is a disease of global importance. In Brazil, it can cause damage of up to 27%. As resistant cultivars are not available yet, short-term disease control relies on the use of fungicides. The first step to reach effective management is to identify potent fungicides. In vitro experiments were conducted to determine the inhibitory concentration 50% (IC50 for mycelial growth or conidial germination, according to the chemical group of fungicides, of five Fusarium graminearum isolates of different origins. The following demethylation inhibitor (DMI fungicides were tested: epoxiconazole, cyproconazole, metconazole, prochloraz, protioconazole and tebuconazole. In addition, azoxystrobin, kresoxim-methyl, pyraclostrobin and trifloxystrobin were included in the study, representing Quinone outside inhibitor fungicides (QoI, as well as a tubulin synthesis inhibitor, carbendazim and two ready mixtures, trifloxystrobin + tebuconazole or trifloxistrobin + prothioconazole. DMI's showed lower IC50 values compared to the QoI's. For the five tested isolates, in the overall mean, IC50 considering mycelial growth ranged for DMI's from 0.01 mg/L (metconazole, prochloraz and prothioconazole to 0.12 mg/L (cyproconazole and considering conidial germination for QoI's from 0.21 mg/L (azoxystrobin to 1.33 mg/L (trifloxystrobin. The IC50 for carbendazim was 0.07 mg/L. All tested isolates can be considered sensitive to the studied DMI's, although certain differences in sensitivity could be detected between the isolates originating from one same state.

  14. Acute toxicity of Headline® fungicide to Blanchard's cricket frogs (Acris blanchardi).

    Science.gov (United States)

    Cusaac, J Patrick W; Morrison, Shane A; Belden, Jason B; Smith, Loren M; McMurry, Scott T

    2016-04-01

    Previous laboratory studies have suggested that pyraclostrobin-containing fungicide formulations are toxic to amphibians at environmentally relevant concentrations. However, it is unknown if all pyraclostrobin formulations have similar toxicity and if toxicity occurs in different amphibian species. We investigated the acute toxicity of two formulations, Headline(®) fungicide and Headline AMP(®) fungicide, to Blanchard's cricket frogs (Acris blanchardi) based on a direct overspray scenario. In addition, we examined body residues of fungicide active ingredients in A. blanchardi following direct exposure to Headline AMP fungicide. Headline fungicide and Headline AMP fungicide had similar toxicity to A. blanchardi with calculated median lethal doses of 2.1 and 1.7 µg pyraclostrobin/cm(2), respectively, which are similar to the suggested maximum label rate in North American corn (2.2 and 1.52 µg pyraclostrobin/cm(2), respectively). Tissue concentrations of pyraclostrobin were lower than predicted based on full uptake of a direct dose, and did not drop during the first 24 h after exposure. Headline fungicides at corn application rates are acutely toxic to cricket frogs, but acute toxicity in the field will depend on worst-case exposure.

  15. Toxicity, sublethal effects, and potential modes of action of select fungicides on freshwater fish and invertebrates

    Science.gov (United States)

    Elskus, Adria A.

    2012-01-01

    Despite decades of agricultural and urban use of fungicides and widespread detection of these pesticides in surface waters, relatively few data are available on the effects of fungicides on fish and invertebrates in the aquatic environment. Nine fungicides are reviewed in this report: azoxystrobin, boscalid, chlorothalonil, fludioxonil, myclobutanil, fenarimol, pyraclostrobin, pyrimethanil, and zoxamide. These fungicides were identified as emerging chemicals of concern because of their high or increasing global use rates, detection frequency in surface waters, or likely persistence in the environment. A review of the literature revealed significant sublethal effects of fungicides on fish, aquatic invertebrates, and ecosystems, including zooplankton and fish reproduction, fish immune function, zooplankton community composition, metabolic enzymes, and ecosystem processes, such as leaf decomposition in streams, among other biological effects. Some of these effects can occur at fungicide concentrations well below single-species acute lethality values (48- or 96-hour concentration that effects a response in 50 percent of the organisms, that is, effective concentration killing 50 percent of the organisms in 48 or 96 hours) and chronic sublethal values (for example, 21-day no observed adverse effects concentration), indicating that single-species toxicity values may dramatically underestimate the toxic potency of some fungicides. Fungicide modes of toxic action in fungi can sometimes reflect the biochemical and (or) physiological effects of fungicides observed in vertebrates and invertebrates; however, far more studies are needed to explore the potential to predict effects in nontarget organisms based on specific fungicide modes of toxic action. Fungicides can also have additive and (or) synergistic effects when used with other fungicides and insecticides, highlighting the need to study pesticide mixtures that occur in surface waters. For fungicides that partition to

  16. Determination of minimum inhibitory concentrations of itraconazole, terbinafine and ketoconazole against dermatophyte species by broth microdilution method.

    Science.gov (United States)

    Bhatia, V K; Sharma, P C

    2015-01-01

    Various antifungal agents both topical and systemic have been introduced into clinical practice for effectively treating dermatophytic conditions. Dermatophytosis is the infection of keratinised tissues caused by fungal species of genera Trichophyton, Epidermophyton and Microsporum, commonly known as dermatophytes affecting 20-25% of the world's population. The present study aims at determining the susceptibility patterns of dermatophyte species recovered from superficial mycoses of human patients in Himachal Pradesh to antifungal agents; itraconazole, terbinafine and ketoconazole. The study also aims at determining the minimum inhibitory concentrations (MICs) of these agents following the recommended protocol of Clinical and Laboratory Standards Institute (CLSI) (M38-A2). A total of 53 isolates of dermatophytes (T. mentagrophyte-34 in no., T. rubrum-18 and M. gypseum-1) recovered from the superficial mycoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008) for filamentous fungi was followed for determining the susceptibility of dermatophyte species. T. mentagrophyte isolates were found more susceptible to both itraconazole and ketoconazole as compared to terbinafine (MIC50: 0.125 µg/ml for itraconazole, 0.0625 µg/ml for ketoconazole and 0.5 µg/ml for terbinafine). Three isolates of T. mentagrophytes (VBS-5, VBSo-3 and VBSo-73) and one isolate of T. rubrum (VBPo-9) had higher MIC values of itraconazole (1 µg/ml). Similarly, the higher MIC values of ketoconazole were observed in case of only three isolates of T. mentagrophyte (VBSo-30 = 2 µg/ml; VBSo-44, VBM-2 = 1 µg/ml). The comparative analysis of the three antifungal drugs based on t-test revealed that 'itraconazole and terbinafine' and 'terbinafine and ketoconazole' were found independent based on the P terbinafine and ketoconazole'. The MIC values observed in the present study based on standard protocol M38-A2 of CLSI 2008 might serve as reference for further studies

  17. Determination of minimum inhibitory concentrations of itraconazole, terbinafine and ketoconazole against dermatophyte species by broth microdilution method

    Directory of Open Access Journals (Sweden)

    V K Bhatia

    2015-01-01

    Full Text Available Purpose: Various antifungal agents both topical and systemic have been introduced into clinical practice for effectively treating dermatophytic conditions. Dermatophytosis is the infection of keratinised tissues caused by fungal species of genera Trichophyton, Epidermophyton and Microsporum, commonly known as dermatophytes affecting 20–25% of the world's population. The present study aims at determining the susceptibility patterns of dermatophyte species recovered from superficial mycoses of human patients in Himachal Pradesh to antifungal agents; itraconazole, terbinafine and ketoconazole. The study also aims at determining the minimum inhibitory concentrations (MICs of these agents following the recommended protocol of Clinical and Laboratory Standards Institute (CLSI (M38-A2. Methodology: A total of 53 isolates of dermatophytes (T. mentagrophyte-34 in no., T. rubrum-18 and M. gypseum-1 recovered from the superficial mycoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008 for filamentous fungi was followed for determining the susceptibility of dermatophyte species. Results: T. mentagrophyte isolates were found more susceptible to both itraconazole and ketoconazole as compared to terbinafine (MIC50: 0.125 µg/ml for itraconazole, 0.0625 µg/ml for ketoconazole and 0.5 µg/ml for terbinafine. Three isolates of T. mentagrophytes (VBS-5, VBSo-3 and VBSo-73 and one isolate of T. rubrum (VBPo-9 had higher MIC values of itraconazole (1 µg/ml. Similarly, the higher MIC values of ketoconazole were observed in case of only three isolates of T. mentagrophyte (VBSo-30 = 2 µg/ml; VBSo-44, VBM-2 = 1 µg/ml. The comparative analysis of the three antifungal drugs based on t-test revealed that 'itraconazole and terbinafine' and 'terbinafine and ketoconazole' were found independent based on the P < 0.005 in case of T. mentagrophyte isolates. In case of T. rubrum, the similarity existed between MIC values of 'itraconazole and

  18. [Effect of five fungicides on growth of Glycyrrhiza uralensis and efficiency of mycorrhizal symbiosis].

    Science.gov (United States)

    Li, Peng-ying; Yang, Guang; Zhou, Xiu-teng; Zhou, Liane-yun; Shao, Ai-juan; Chen, Mei-lan

    2015-12-01

    In order to obtain the fungicides with minimal impact on efficiency of mycorrhizal symbiosis, the effect of five fungicides including polyoxins, jinggangmycins, thiophanate methylate, chlorothalonil and carbendazim on the growth of medicinal plant and efficiency of mycorrhizal symbiosis were studied. Pot cultured Glycyrrhiza uralensis was treated with different fungicides with the concentration that commonly used in the field. 60 d after treated with fungicides, infection rate, infection density, biomass indexes, photosyn- thetic index and the content of active component were measured. Experimental results showed that carbendazim had the strongest inhibition on mycorrhizal symbiosis effect. Carbendazim significantly inhibited the mycorrhizal infection rate, significantly suppressed the actual photosynthetic efficiency of G. uralensis and the most indicators of biomass. Polyoxins showed the lowest inhibiting affection. Polyoxins had no significant effect on mycorrhizal infection rate, the actual photosynthetic efficiency of G. uralensis and the most indicators of biomass. The other three fungicides also had an inhibitory effect on efficiency of mycorrhizal symbiosis, and the inhibition degrees were all between polyoxins's and carbendazim's. The author considered that fungicide's inhibition degree on mycorrhizal effect might be related with the species of fungicides, so the author suggested that the farmer should try to choose bio-fungicides like polyoxins.

  19. Fungicide application and phosphorus uptake by hyphae of arbuscular mycorrhizal fungi into field-grown peas

    DEFF Research Database (Denmark)

    Schweiger, P.F.; Spliid, N.H.; Jakobsen, I.

    2001-01-01

    The effect of two commercial fungicide formulations on phosphorus (P) uptake into peas via hyphae of a native arbuscular mycorrhizal (AM) fungal community was examined in the field. The fungicides contained carbendazim or a mixture of propiconazole and fenpropimorph as their active ingredients...... from overall P uptake, Fungicides were added to the soil inside the HCs at concentrations assumed to reflect their concentration in the surrounding soil. At two harvests, plant growth, total P and P-32 uptake as well as root length density and AM root colonisation were measured. Length of hyphae inside...

  20. Strong lethality and teratogenicity of strobilurins on Xenopus tropicalis embryos: Basing on ten agricultural fungicides

    International Nuclear Information System (INIS)

    Li, Dan; Liu, Mengyun; Yang, Yongsheng; Shi, Huahong; Zhou, Junliang; He, Defu

    2016-01-01

    Agricultural chemical inputs have been considered as a risk factor for the global declines in amphibian populations, yet the application of agricultural fungicides has increased dramatically in recent years. Currently little is known about the potential toxicity of fungicides on the embryos of amphibians. We studied the effects of ten commonly used fungicides (four strobilurins, two SDHIs, two triazoles, fludioxonil and folpet) on Xenopus tropicalis embryos. Lethal and teratogenic effects were respectively examined after 48 h exposure. The median lethal concentrations (LC50s) and the median teratogenic concentrations (TC50s) were determined in line with actual exposure concentrations. These fungicides except two triazoles showed obvious lethal effects on embryos; however LC50s of four strobilurins were the lowest and in the range of 6.81–196.59 μg/L. Strobilurins, SDHIs and fludioxonil induced severe malformations in embryos. Among the ten fungicides, the lowest TC50s were observed for four strobilurins in the range of 0.61–84.13 μg/L. The teratogenicity shared similar dose–effect relationship and consistent phenotypes mainly including microcephaly, hypopigmentation, somite segmentation and narrow fins. The findings indicate that the developmental toxicity of currently-used fungicides involved with ecologic risks on amphibians. Especially strobilurins are highly toxic to amphibian embryos at μg/L level, which is close to environmentally relevant concentrations. - Highlights: • Effects of ten agricultural fungicides were tested on Xenopus tropicalis embryos. • Strobilurin fungicides showed strong lethal and teratogenic effects on embryos. • Lowest LC50 and TC50 were observed for strobilurins in ten fungicides. • μg/L level of toxic concentrations for strobilurins was environmentally relevant. • Teratogenicity shared similar dose–effect relationship and main phenotypes. - Strobilurins induced strong lethality and teratogenicity on Xenopus

  1. Fungicide selective for basidiomycetes.

    Science.gov (United States)

    Edgington, L V; Walton, G S; Miller, P M

    1966-07-15

    Concentrations of 2,3-dihydro-5-carboxanilido-6-methyl-1,4-oxathiin lower than 8 parts per million prevented mycelial growth of a number of Basidiomycetes. By contrast, mycelial growth of various other fungi-Phycomycetes, Ascomycetes, and Deuteromycetes-was 50 percent inhibited only by concentrations of 32 ppm or higher. Two exceptions to this pattern of selective fungitoxicity were found:an isolate of Rhizoctonia solani was not as sensitive as other Basidiomycetes, and the deuteromycete Verticillium alboatrum was inhibited by lower concentrations than affected other fungi in this group. Spore germination of two Basidiomycetes, Uromyces phaseoli and Ustilago nuda, was inhibited 95 percent or more at 10 ppm.

  2. Phytopharmacological studies on the rice diseases. III. Fungitoxicity of the different dust fungicides evaluated by protoplasm coagulation in conidia of Cochliobolus miyabeanus

    Energy Technology Data Exchange (ETDEWEB)

    Hashioka, Y; Ikegami, H

    1956-01-01

    The modes of reaction of fungal conidia to fungicides (mercury and copper compounds) varied with the concentration of fungicide. At lower fugicide concentrations, restriction of elongation of germ-tubes was noted. At high concentrations, there was no germination accompanied by vacuolation. At the highest concentrations, conidia protoplasm was coagulated.

  3. Isoflavone formononetin from red propolis acts as a fungicide against Candida sp

    Directory of Open Access Journals (Sweden)

    Michelline Viviane Marques das Neves

    2016-03-01

    Full Text Available Abstract A bioassay-guided fractionation of two samples of Brazilian red propolis (from Igarassu, PE, Brazil, hereinafter propolis 1 and 2 was conducted in order to determine the components responsible for its antimicrobial activity, especially against Candida spp. Samples of both the crude powdered resin and the crude ethanolic extract of propolis from both locations inhibited the growth of all 12 tested Candida strains, with a minimum inhibitory concentration of 256 µg/mL. The hexane, acetate and methanol fractions of propolis 1 also inhibited all strains with minimum inhibitory concentration values ranging from 128 to 512 µg/mL for the six bacteria tested and from 32 to 1024 µg/mL for the yeasts. Similarly, hexane and acetate fractions of propolis sample 2 inhibited all microorganisms tested, with minimum inhibitory concentration values of 512 µg/mL for bacteria and 32 µg/mL for yeasts. The extracts were analyzed by HPLC and their phenolic profile allowed us to identify and quantitate one phenolic acid and seven flavonoids in the crude ethanolic extract. Formononetin and pinocembrin were the major constituents amongst the identified compounds. Formononetin was detected in all extracts and fractions tested, except for the methanolic fraction of sample 2. The isolated isoflavone formononetin inhibited the growth of all the microorganisms tested, with a minimum inhibitory concentration of 200 µg/mL for the six bacteria strains tested and 25 µg/mL for the six yeasts. Formononetin also exhibited fungicidal activity against five of the six yeasts tested. Taken together our results demonstrate that the isoflavone formononetin is implicated in the reported antimicrobial activity of red propolis.

  4. Additive and synergistic antiandrogenic activities of mixtures of azol fungicides and vinclozolin

    Energy Technology Data Exchange (ETDEWEB)

    Christen, Verena [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); Crettaz, Pierre [Federal Office of Public Health, Division Chemical Products, 3003 Bern (Switzerland); Fent, Karl, E-mail: karl.fent@fhnw.ch [University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences, Gründenstrasse 40, CH-4132 Muttenz (Switzerland); ETH Zürich, Department of Environmental System Sciences, Institute of Biogeochemistry and Pollution Dynamics, Universitätsstrasse 16, CH-8092 Zürich (Switzerland)

    2014-09-15

    Objective: Many pesticides including pyrethroids and azole fungicides are suspected to have an endocrine disrupting property. At present, the joint activity of compound mixtures is only marginally known. Here we tested the hypothesis that the antiandrogenic activity of mixtures of azole fungicides can be predicted by the concentration addition (CA) model. Methods: The antiandrogenic activity was assessed in MDA-kb2 cells. Following assessing single compounds activities mixtures of azole fungicides and vinclozolin were investigated. Interactions were analyzed by direct comparison between experimental and estimated dose–response curves assuming CA, followed by an analysis by the isobole method and the toxic unit approach. Results: The antiandrogenic activity of pyrethroids deltamethrin, cypermethrin, fenvalerate and permethrin was weak, while the azole fungicides tebuconazole, propiconazole, epoxiconazole, econazole and vinclozolin exhibited strong antiandrogenic activity. Ten binary and one ternary mixture combinations of five antiandrogenic fungicides were assessed at equi-effective concentrations of EC{sub 25} and EC{sub 50}. Isoboles indicated that about 50% of the binary mixtures were additive and 50% synergistic. Synergism was even more frequently indicated by the toxic unit approach. Conclusion: Our data lead to the conclusion that interactions in mixtures follow the CA model. However, a surprisingly high percentage of synergistic interactions occurred. Therefore, the mixture activity of antiandrogenic azole fungicides is at least additive. Practice: Mixtures should also be considered for additive antiandrogenic activity in hazard and risk assessment. Implications: Our evaluation provides an appropriate “proof of concept”, but whether it equally translates to in vivo effects should further be investigated. - Highlights: • Humans are exposed to pesticide mixtures such as pyrethroids and azole fungicides. • We assessed the antiandrogenicity of

  5. Additive and synergistic antiandrogenic activities of mixtures of azol fungicides and vinclozolin

    International Nuclear Information System (INIS)

    Christen, Verena; Crettaz, Pierre; Fent, Karl

    2014-01-01

    Objective: Many pesticides including pyrethroids and azole fungicides are suspected to have an endocrine disrupting property. At present, the joint activity of compound mixtures is only marginally known. Here we tested the hypothesis that the antiandrogenic activity of mixtures of azole fungicides can be predicted by the concentration addition (CA) model. Methods: The antiandrogenic activity was assessed in MDA-kb2 cells. Following assessing single compounds activities mixtures of azole fungicides and vinclozolin were investigated. Interactions were analyzed by direct comparison between experimental and estimated dose–response curves assuming CA, followed by an analysis by the isobole method and the toxic unit approach. Results: The antiandrogenic activity of pyrethroids deltamethrin, cypermethrin, fenvalerate and permethrin was weak, while the azole fungicides tebuconazole, propiconazole, epoxiconazole, econazole and vinclozolin exhibited strong antiandrogenic activity. Ten binary and one ternary mixture combinations of five antiandrogenic fungicides were assessed at equi-effective concentrations of EC 25 and EC 50 . Isoboles indicated that about 50% of the binary mixtures were additive and 50% synergistic. Synergism was even more frequently indicated by the toxic unit approach. Conclusion: Our data lead to the conclusion that interactions in mixtures follow the CA model. However, a surprisingly high percentage of synergistic interactions occurred. Therefore, the mixture activity of antiandrogenic azole fungicides is at least additive. Practice: Mixtures should also be considered for additive antiandrogenic activity in hazard and risk assessment. Implications: Our evaluation provides an appropriate “proof of concept”, but whether it equally translates to in vivo effects should further be investigated. - Highlights: • Humans are exposed to pesticide mixtures such as pyrethroids and azole fungicides. • We assessed the antiandrogenicity of pyrethroids and

  6. Comparison of in vitro efficacy of linezolid and vancomycin by determining their minimum inhibitory concentrations against methicillin resistant Staphylococcus aureus (MRSA)

    International Nuclear Information System (INIS)

    Kaleem, F.; Usman, J.; Hassan, A.

    2011-01-01

    Objectives: To compare the in vitro activities of vancomycin and linezolid against methicillin resistant Staphyloccus aureus in our set up to help in formulating a better empirical treatment and reduce the emergence of vancomycin resistant Staphylococcus aureus. Methods: The study was conducted over a period of 6 months(July 1, 2009 - Dec 1, 2009). Fifty Methicillin resistant Staphylococcus aureus isolated from the clinical isolates of Military Hospital Rawalpindi were subjected to the determination of Minimum inhibitory concentrations of linezolid and vancomycin using E-strips. Results: All the isolated organisms were uniformly susceptible to both the antibiotics. Vancomycin showed higher minimum inhibitory concentrations (MICs) as compared to linezolid MICs. Conclusion: This study suggests that linezolid and vancomycin have similar in vitro efficacy for methicillin resistant Staphyloccus aureus infections. (author)

  7. Comparative efficacy of different fungicides against fusarium wilt of chickpea (cicer arietinum l.)

    International Nuclear Information System (INIS)

    Maitlo, S.A.

    2014-01-01

    Fusarium wilt caused by Fusarium oxysporum f. sp. ciceris (Foc) is the most serious and widespread disease of chickpea, causing a 100% loss under favorable conditions. Fourteen fungicides were evaluated against wilt pathogen In vitro with five different concentrations ranging from 1-10000 ppm. Among these only Carbendazim and Thiophanate-methyl was found as the most effective at all used concentrations. Other fungicides like Aliette, Nativo, Hombre-excel and Dividend star were found to be moderately effective. Whereas, remaining fungicides were ineffective against the targeted pathogen. Generally, a positive co-relation was observed between increasing concentrations of the tested fungicides and inhibition of Foc. Based on In vitro results Carbendazim, Thiophanate-methyl, Aliette, Dividend-star, Hombre-excel, Score and Nativo were selected for pot and field experiments. The higher concentrations of the few fungicides completely inhibited the pathogen as well as found to be phytotoxic and suppressed the plant growth while lower concentrations promoted the growth of chickpea plants. On over all bases, the Carbendazim and Thiophanate-methyl, followed by Aliette and Nativo were more effective in reducing the impact of pathogen as well as enhancing the plant growth in greenhouse experiment. Under field conditions, all fungicides except Score remarkably decreased the disease development and subsequently increased the plant growth as well as grain yield as compared to untreated plants. (author)

  8. Terrestrial exposure and effects of Headline AMP(®) Fungicide on amphibians.

    Science.gov (United States)

    Cusaac, J Patrick W; Mimbs, William H; Belden, Jason B; Smith, Loren M; McMurry, Scott T

    2015-08-01

    Recent studies have demonstrated that a pyraclostrobin-containing fungicide (Headline(®) Fungicide--Headline(®) Fungicide and Headline AMP(®) Fungicide are registered trademarks of BASF) is toxic to amphibians at environmentally relevant concentrations. However, these studies were performed in a laboratory setting of a worst-case direct exposure in clean media. Interception of spray by the crop canopy and ground cover used by animals for security cover will influence exposure. Thus, risk to amphibians is unclear in an environmentally realistic field environment. We tested exposure and toxicity of Headline AMP(®) Fungicide to amphibians in multiple agricultural habitat scenarios (e.g., within treated crop vs. grassy areas adjacent to crop) and at two rates during routine aerial application. Specifically, we placed Woodhouse's toads (Bufo woodhousii) and Blanchard's cricket frogs (Acris blanchardi) in enclosures located within treated and untreated corn (VT stage, approximate height = 3 m), and in the potential drift area (adjacent to treated corn) during aerial application of Headline AMP Fungicide at either 731 or 1052 ml/ha (70 and 100 % the maximum application rate in corn, respectively). Mean concentrations of pyraclostrobin measured at ground level were ≤19 % of nominal application rate in all areas. Overall, mean mortality of recovered individuals of both species was ≤15 %, and mortality within Headline AMP Fungicide-treated corn (where risk was anticipated to be highest) was <10 %. It is important to understand that application timing, interception by the crop canopy (which varies both within and between crop systems), and timing of amphibian presence in the crop field influences risk of exposure and effects; however, our results demonstrate that amphibians inhabiting VT stage corn during routine aerial application of Headline AMP Fungicide are at low risk for acute mortality, matching existing laboratory results from acute toxicity studies of

  9. Control of Vascular Streak Dieback Disease of Cocoa with Flutriafol Fungicides

    Directory of Open Access Journals (Sweden)

    Febrilia Nur'aini

    2014-12-01

    Full Text Available Vascular streak dieback caused by the fungus Oncobasidium theobromae is one of the important diseases in cocoa crop in Indonesia. One approach to control the disease is by using fungicides. The aim of this research was to determine the effect of class triazole fungicides to the intensity of the vascular streak dieback disease on cocoa seedling phase, immature and mature cocoa. Experiments were conducted in Kotta Blater, PTPN XII and Kaliwining, Indonesian  Coffee and Cocoa Research Institute. Flutriafol 250 g/l with a concentration 0,05%, 0,1% and 0,15% foliar sprayed on cocoa seedlings, immature and mature cocoa. Active compound combination of Azoxystrobin and Difenoconazole with 0,1% concentration used as a comparation fungicides. The result showed that Flutriafol with 0,05%, 0,1% and 0,15% concentration and Azoxystrobin & Difenoconazol with 0,1% concentration could suppress the vascular streak dieback disease on seedlings. On immature plants, the application of Flutriafol was not effectively suppress the vascular streak dieback disease whereas the fungicide comparison could suppress with the efficacy level of 46.22%. On mature plants,both of fungicides could not suppress the vascular streak dieback disease. Key words: Fungicide, cocoa, vascular streak dieback, triazole, flutriafol, azoxystrobin+difenoconazol

  10. Leaching of two fungicides in spent mushroom substrate amended soil: Influence of amendment rate, fungicide ageing and flow condition.

    Science.gov (United States)

    Álvarez-Martín, Alba; Sánchez-Martín, María J; Ordax, José M; Marín-Benito, Jesús M; Sonia Rodríguez-Cruz, M

    2017-04-15

    A study has been conducted on the leaching of two fungicides, tebuconazole and cymoxanil, in a soil amended with spent mushroom substrate (SMS), with an evaluation of how different factors influence this process. The objective was based on the potential use of SMS as a biosorbent for immobilizing pesticides in vulnerable soils, and the need to know how it could affect the subsequent transport of these retained compounds. Breakthrough curves (BTCs) for 14 C-fungicides, non-incubated and incubated over 30days, were obtained in columns packed with an unamended soil (S), and this soil amended with SMS at rates of 5% (S+SMS5) and 50% (S+SMS50) under saturated and saturated-unsaturated flows. The highest leaching of tebuconazole (>50% of the total 14 C added) was found in S when a saturated water flow was applied to the column, but the percentage of leached fungicide decreased when a saturated-unsaturated flow was applied in both SMS-amended soils. Also a significant decrease in leaching was observed for tebuconazole after incubation in the column, especially in S+SMS50 when both flows were applied. Furthermore, cymoxanil leaching was complete in S and S+SMS when a saturated flow was applied, and maximum peak concentrations were reached at 1pore volume (PV), although BTCs showed peaks with lower concentrations in S+SMS. The amounts of cymoxanil retained only increased in S+SMS when a saturated-unsaturated flow was applied. A more relevant effect of SMS for reducing the leaching of fungicide was observed when cymoxanil was previously incubated in the column, although mineralization was enhanced in this case. These results are of interest for extending SMS application on the control of the leaching of fungicides with different physicochemical characteristics after different ageing times in the soil and water flow conditions applied. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Evaluation of fungicides and biopesticides for the control of fusarium wilt of tomato

    International Nuclear Information System (INIS)

    Akhtar, T.; Iftikhar, Y.

    2017-01-01

    Fusarium wilt is highly destructive soil borne pathogen in tomato. Current study was carried out to evaluate commercially available fungicides and bio-fungicides in-vitro and in-vivo, for their efficacy against Fusarium oxysporum f.sp. lycopersici. Firstly four fungicides were evaluated under laboratory conditions. Three promising fungicides, two biopesticides and Trichoderma harzianum were further applied both in greenhouse and field experiments. During in-vitro studies PDA amended with fungicides with different treatments at the rate 1% almost completely inhibited the growth of Fol with varying degree of success whereas Nativo being the most effective treatment with 98% reduction in growth as compared to control. Nativo significantly reduced the disease incidence (32.75 %) at concentration of 1%. While Poly-beta-hydroxyl-butyric-acid effectively promoted the tomato growth. Maximum reduction in disease (30.14 %) was expressed by Nativo followed by Teagro (25.06 %) under field conditions. Nativo was found to be the most effective fungicide for management of Fol both In vitro and In vivo. Further field evaluations of the fungicides are required. (author)

  12. Evaluating Susceptibility to Commercial Fungicide of Endophytic Fungi Isolated from Roses (Rosa hybrida

    Directory of Open Access Journals (Sweden)

    Ingrid Carolina Corredor Perilla

    2007-01-01

    Full Text Available Fungal endophytes have shown their potential as biocontrol agents; however, their application in commercial fields remains limited. Continuously applying fungicides to crops (specifically to roses may have harmful effects on endophyte growth. Endophytic fungi were isolated from R. hybrida and their susceptibility to fungicides regularly used for controlling important pathogens was analysed. This was performed in vitro, mixing several fungicide concentrations with standard medium for fungal endophytes; growth inhibition was then measured. The susceptibility of Botrytis cinerea (3015 strain, one of the most important pathogens affecting roses in Colombia, was also assessed using the same protocols. Active ingredients, such as boscalid, captan, iprodione and pyrimethanyl, showed susceptibility ranging from not sensitive (³73.75% to regularly sensitive (³48.75% - <61.25% for 45.45% of the fungal endophytes assessed. Endophytic fungi were highly susceptible to fungicides such as pyrimethanyl, carboxin plus thiram, fludioxonyl plus ciprodinyl and prochloraz. B. cinerea (3015 strain presented high susceptibility (<23.75% to fungicides such as pyrimethanyl, carboxin and thiram, fludioxonil and ciprodinyl, prochloraz. Although B. cinerea showed the greatest growth in controls, the endophytic fungi being assessed grew better in different media with fungicides. The results revealed some of these fungal endophytes’ potential for integrated pest management (IPM in roses in Colombia (3002, 3003, 3004, 3005 and 3006 strains, taking into account correct application time, application frequency and both fungal endophyte and fungicide dosage which may greatly limit fungal endophyte growth.

  13. The toxicity of the fungicide Propiconazole to soil flagellates

    DEFF Research Database (Denmark)

    Ekelund, Flemming; Westergaard, Kamma; Søe, Dorthe

    2000-01-01

    We investigated the effects of the ergosterol-inhibiting fungicide, propiconazole {1-[[2-(2,4-dichlorphenyl) - 4 - propyl - 1,3 - dioxolan - 2 - yl]methyl] - 1H - 1,2,4 triazole; Tilt}, on mixed natural populations of bacterivorous and fungivorous flagellates in soil and on single species...... of bacterivorous flagellates in liquid culture. The fungicide affected a mixed natural population of fungivorous flagellates less than the population of bacterivorous flagellates. Our results indicated that the effects of propiconazole on flagellates are direct toxic effects and not effects mediated via their food....... All tested types of flagellates were significantly harmed when exposed to the concentration of propiconazole normally applied to agricultural fields (625¿mg l-1). However, when exposed to the concentration of propiconazole which we expect in the soil water phase after application (ca. 0.6¿mg l-1...

  14. Effects of current-use fungicides and their mixtures on the feeding and survival of the key shredder Gammarus fossarum.

    Science.gov (United States)

    Zubrod, J P; Baudy, P; Schulz, R; Bundschuh, M

    2014-05-01

    Fungicides are frequently applied in agriculture and are subsequently detected in surface waters in total concentrations of up to several tens of micrograms per liter. These concentrations imply potential effects on aquatic communities and fundamental ecosystem functions such as leaf litter breakdown. In this context, the present study investigates sublethal and lethal effects of organic (azoxystrobin, carbendazim, cyprodinil, quinoxyfen, and tebuconazole) and inorganic (three copper (Cu)-based substances and sulfur) current-use fungicides and their mixtures on the key leaf-shredding invertebrate Gammarus fossarum. The feeding activity of fungicide-exposed gammarids was quantified as sublethal endpoint using a static (organic fungicides; 7 d test duration) or a semi-static (inorganic fungicides; 6 d test duration with a water exchange after 3 d) approach (n=30). EC50-values of organic fungicides were generally observed at concentrations resulting in less than 20% mortality, with the exception of carbendazim. With regard to feeding, quinoxyfen was the most toxic organic fungicide, followed by cyprodinil, carbendazim, azoxystrobin, and tebuconazole. Although all tested organic fungicides have dissimilar (intended) modes of action, a mixture experiment revealed a synergistic effect on gammarids' feeding at high concentrations when using "independent action" as the reference model (∼35% deviation between predicted and observed effect). This may be explained by the presence of a synergizing azole fungicide (i.e. tebuconazole) in this mixture. Furthermore, lethal concentrations of all Cu-based fungicides assessed in this study were comparable amongst one another. However, they differed markedly in their effective concentrations when using feeding activity as the endpoint, with Cu-sulfate being most toxic, followed by Cu-hydroxide and Cu-octanoate. In contrast, sulfur neither affected survival nor the feeding activity of gammarids (up to ∼5 mg/L) but reduced Cu

  15. Minimum inhibitory concentration of vancomycin to methicillin resistant Staphylococcus aureus isolated from different clinical samples at a tertiary care hospital in Nepal

    Directory of Open Access Journals (Sweden)

    Arjun Ojha Kshetry

    2016-07-01

    Full Text Available Abstract Background Methicillin resistant Staphylococcus aureus (MRSA has evolved as a serious threat to public health. It has capability to cause infections not only in health care settings but also in community. Due to the multidrug resistance shown by MRSA, there are limited treatment options for the infections caused by this superbug. Vancomycin is used as the drug of choice for the treatment of infections caused by MRSA. Different studies from all around the world have documented the emergence of strains of S. aureus those are intermediate sensitive or resistant to vancomycin. And recently, there have been reports of reduced susceptibility of MRSA to vancomycin, from Nepal also. So the main purpose of this study was to determine the minimum inhibitory concentration (MIC of vancomycin to methicillin resistant S. aureus isolated from different clinical specimens. Methods Total 125 strains of S. aureus isolated from different clinical samples at KIST Medical College and Teaching Hospital, Lalitpur, Nepal from Nov 2012 to June 2013, were subjected to MRSA detection by cefoxitin disc diffusion method. The minimum inhibitory concentrations of vancomycin to confirmed MRSA strains were determined by agar dilution method. Yellow colored colonies in mannitol salt agar, which were gram positive cocci, catalase positive and coagulase positive were confirmed to be S. aureus. Results Among, total 125 S. aureus strains isolated; 47(37.6% were MRSA. Minimum inhibitory concentrations of vancomycin to the strains of MRSA ranged from 0.125 μg/ml to 1 μg/ml. Conclusion From our findings we concluded that the rate of isolation of MRSA among all the strains of S. aureus isolated from clinical samples was very high. However, none of the MRSA strains were found to be vancomycin intermediate-sensitive or vancomycin-resistant.

  16. On the validity of setting breakpoint minimum inhibition concentrations at one quarter of the plasma concentration achieved following oral administration of oxytetracycline

    DEFF Research Database (Denmark)

    Coyne, R.; Samuelsen, O.; Bergh, Ø.

    2004-01-01

    Plasma concentrations of oxytetracycline (OTC) were established in two Atlantic salmon (Salmo salar) pre-smolts populations after they had received OTC medicated feed at a rate of 75 mg OTC/kg over 10 days. One population was experiencing an epizootic of furunculosis in a commercial freshwater farm...

  17. Effects of two commonly used fungicides on the amphipod Austrochiltonia subtenuis.

    Science.gov (United States)

    Vu, Hung T; Keough, Michael J; Long, Sara M; Pettigrove, Vincent J

    2017-03-01

    Fungicides are used widely in agriculture and have been detected in adjacent rivers and wetlands. However, relatively little is known about the potential effects of fungicides on aquatic organisms. The present study investigated the effects of 2 commonly used fungicides, the boscalid fungicide Filan ® and the myclobutanil fungicide Systhane ™ 400 WP, on life history traits (survival, growth, and reproduction) and energy reserves (lipid, protein, and glycogen content) of the amphipod Austrochiltonia subtenuis under laboratory conditions, at concentrations detected in aquatic environments. Amphipods were exposed to 3 concentrations of Filan (1 μg active ingredient [a.i.]/L, 10 μg a.i./L, and 40 μg a.i./L) and Systhane (0.3 μg a.i./L, 3 μg a.i./L, and 30 μg a.i./L) over 56 d. Both fungicides had similar effects on the amphipod at the organism level. Reproduction was the most sensitive endpoint, with offspring produced in controls but none produced in any of the fungicide treatments, and total numbers of gravid females in all fungicide treatments were reduced by up to 95%. Female amphipods were more sensitive than males in terms of growth. Systhane had significant effects on survival at all concentrations, whereas significant effects of Filan on survival were observed only at 10 μg a.i./L and 40 μg a.i./L. The effects of fungicides on energy reserves of the female amphipod were different. Filan significantly reduced amphipod protein content, whereas Systhane significantly reduced the lipid content. The present study demonstrates wide-ranging effects of 2 common fungicides on an ecologically important species that has a key role in trophic transfer and nutrient recycling in aquatic environments. These results emphasize the importance of considering the long-term effects of fungicides in the risk assessment of aquatic ecosystems. Environ Toxicol Chem 2017;36:720-726. © 2016 SETAC. © 2016 SETAC.

  18. Ag doped hollow TiO2 nanoparticles as an effective green fungicide against Fusarium solani and Venturia inaequalis phytopathogens

    Science.gov (United States)

    Sankar Boxi, Siddhartha; Mukherjee, Khushi; Paria, Santanu

    2016-02-01

    Chemical-based pesticides are widely used in agriculture to protect crops from insect infestation and diseases. However, the excessive use of highly toxic pesticides causes several human health (neurological, tumor, cancer) and environmental problems. Therefore nanoparticle-based green pesticides have become of special importance in recent years. The antifungal activities of pure and Ag doped (solid and hollow) TiO2 nanoparticles are studied against two potent phytopathogens, Fusarium solani (which causes Fusarium wilt disease in potato, tomato, etc) and Venturia inaequalis (which causes apple scab disease) and it is found that hollow nanoparticles are more effective than the other two. The antifungal activities of the nanoparticles were further enhanced against these two phytopathogens under visible light exposure. The fungicidal effect of the nanoparticles depends on different parameters, such as particle concentration and the intensity of visible light. The minimum inhibitory dose of the nanoparticles for V. inaequalis and F. solani are 0.75 and 0.43 mg/plate. The presence of Ag as a dopant helps in the formation of stable Ag-S and disulfide bonds (R-S-S-R) in cellular protein, which leads to cell damage. During photocatalysis generated •OH radicals loosen the cell wall structure and this finally leads to cell death. The mechanisms of the fungicidal effect of nanoparticles against these two phytopathogens are supported by biuret and triphenyl tetrazolium chloride analyses and field emission electron microscopy. Apart from the fungicidal effect, at a very low dose (0.015 mg/plate) the nanoparticles are successful in arresting production of toxic napthoquinone pigment for F. solani which is related to the fungal pathogenecity. The nanoparticles are found to be effective in protecting potatoes affected by F. solani or other fungi from spoiling.

  19. Ag doped hollow TiO2 nanoparticles as an effective green fungicide against Fusarium solani and Venturia inaequalis phytopathogens

    International Nuclear Information System (INIS)

    Boxi, Siddhartha Sankar; Mukherjee, Khushi; Paria, Santanu

    2016-01-01

    Chemical-based pesticides are widely used in agriculture to protect crops from insect infestation and diseases. However, the excessive use of highly toxic pesticides causes several human health (neurological, tumor, cancer) and environmental problems. Therefore nanoparticle-based green pesticides have become of special importance in recent years. The antifungal activities of pure and Ag doped (solid and hollow) TiO 2 nanoparticles are studied against two potent phytopathogens, Fusarium solani (which causes Fusarium wilt disease in potato, tomato, etc) and Venturia inaequalis (which causes apple scab disease) and it is found that hollow nanoparticles are more effective than the other two. The antifungal activities of the nanoparticles were further enhanced against these two phytopathogens under visible light exposure. The fungicidal effect of the nanoparticles depends on different parameters, such as particle concentration and the intensity of visible light. The minimum inhibitory dose of the nanoparticles for V. inaequalis and F. solani are 0.75 and 0.43 mg/plate. The presence of Ag as a dopant helps in the formation of stable Ag–S and disulfide bonds (R–S–S–R) in cellular protein, which leads to cell damage. During photocatalysis generated • OH radicals loosen the cell wall structure and this finally leads to cell death. The mechanisms of the fungicidal effect of nanoparticles against these two phytopathogens are supported by biuret and triphenyl tetrazolium chloride analyses and field emission electron microscopy. Apart from the fungicidal effect, at a very low dose (0.015 mg/plate) the nanoparticles are successful in arresting production of toxic napthoquinone pigment for F. solani which is related to the fungal pathogenecity. The nanoparticles are found to be effective in protecting potatoes affected by F. solani or other fungi from spoiling. (paper)

  20. Additive and synergistic antiandrogenic activities of mixtures of azol fungicides and vinclozolin.

    Science.gov (United States)

    Christen, Verena; Crettaz, Pierre; Fent, Karl

    2014-09-15

    Many pesticides including pyrethroids and azole fungicides are suspected to have an endocrine disrupting property. At present, the joint activity of compound mixtures is only marginally known. Here we tested the hypothesis that the antiandrogenic activity of mixtures of azole fungicides can be predicted by the concentration addition (CA) model. The antiandrogenic activity was assessed in MDA-kb2 cells. Following assessing single compounds activities mixtures of azole fungicides and vinclozolin were investigated. Interactions were analyzed by direct comparison between experimental and estimated dose-response curves assuming CA, followed by an analysis by the isobole method and the toxic unit approach. The antiandrogenic activity of pyrethroids deltamethrin, cypermethrin, fenvalerate and permethrin was weak, while the azole fungicides tebuconazole, propiconazole, epoxiconazole, econazole and vinclozolin exhibited strong antiandrogenic activity. Ten binary and one ternary mixture combinations of five antiandrogenic fungicides were assessed at equi-effective concentrations of EC25 and EC50. Isoboles indicated that about 50% of the binary mixtures were additive and 50% synergistic. Synergism was even more frequently indicated by the toxic unit approach. Our data lead to the conclusion that interactions in mixtures follow the CA model. However, a surprisingly high percentage of synergistic interactions occurred. Therefore, the mixture activity of antiandrogenic azole fungicides is at least additive. Mixtures should also be considered for additive antiandrogenic activity in hazard and risk assessment. Our evaluation provides an appropriate "proof of concept", but whether it equally translates to in vivo effects should further be investigated. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. CONTROL OF BAGRAS (Eucalyptus deglupta DAMPING-OFF BY FUNGICIDES

    Directory of Open Access Journals (Sweden)

    EMILIO O. ANINO

    2000-01-01

    Full Text Available Selected fungicides were tested to control damp ing-off affecting bagras seedlings in the Central Nursery of the Paper Industries Corporation of the Philippines (PICOP, Surigao del Sur, Philippines. The fungicides, at three concentrations each, were applie d once before seed sowing to control pre-emergence damping-off and applied again after germination to cont rol post-emergence damping-off. Ajax detergent (2g/l H2O, Benlate (0.5 g/1 H2O, Brassicol (1.5 gv'l H 2O, and Fungitox (1.0 g/1 H2O provided the best level of control against the disease. Ajax detergent is the most practical among the best chemicals because it is cheap, locally available, not a heal th hazard, and less polluting.

  2. Method for in vitro screening of aquatic fungicides

    Science.gov (United States)

    Bailey, T.A.

    1983-01-01

    Methods were developed for in vitro screening of candidate aquatic fungicides for efficacy against Achlya fiagellata, A. racemosa, Saprolegnia hypogyna and S. megasperma. Agar plugs containing fungal hyphae, removed from the edge of actively growing colonies, were placed in the depressions of spot plates containing 1a??0, 10a??0 and 100 mg/I of the candidate compounds for 15 or 60 min. After exposure, the plugs were transferred on to filter papers (0a??45-A?m pore) in a holder, rinsed, and then placed on cornmeal agar medium in tri-petri dishes. The plates were checked for mycelial growth after 48, 96 and 168 h of incubation in a lighted (400-800 A?m) environmental control chamber at 20A?2A?C. Criteria for the acceptance or rejection of candidate aquatic fungicides for further study were based on the antifungal spectrum index (ASI) comparisons between respective compounds and malachite green after 48 h and the concentration level producing complete growth inhibition. Candidate compounds whose ASI was less than 50% that of malachite green after 48 h or did not inhibit growth at levels less than 100 mg/l were rejected. This method provides a base from which in vivo and definitive test regimens can be developed. Preliminary in vitro screening of candidate fungicides reduces the need for costly in vivo tests on compounds that have low antifungal activity.

  3. Effect of fungicides on epiphytic yeasts associated with strawberry

    Science.gov (United States)

    Debode, Jane; Van Hemelrijck, Wendy; Creemers, Piet; Maes, Martine

    2013-01-01

    We studied the effect of two commonly used fungicides on the epiphytic yeast community of strawberry. Greenhouse and field experiments were conducted applying Switch (cyprodinil plus fludioxonil) or Signum (boscalid plus pyraclostrobin) to strawberry plants. Yeasts on leaves and fruits were assessed on treated and untreated plants at several time points via plating and denaturing gradient gel electrophoresis (DGGE) analysis. The yeast counts on plates of the treated plants were similar to the control plants. Unripe fruits had 10 times larger yeast concentrations than ripe fruits or leaves. Some dominant yeast types were isolated and in vitro tests showed that they were at least 10 times less sensitive to Switch and Signum as compared with two important fungal strawberry pathogens Botrytis cinerea and Colletotrichum acutatum, which are the targets for the fungicide control. DGGE analysis showed that the applied fungicides had no effect on the composition of the yeast communities, while the growing system, strawberry tissue, and sampling time did affect the yeast communities. The yeast species most commonly identified were Cryptococcus, Rhodotorula, and Sporobolomyces. These results point toward the potential applicability of natural occurring yeast antagonists into an integrated disease control strategy for strawberry diseases.

  4. Occurrence and persistence of fungicides in bed sediments and suspended solids from three targeted use areas in the United States.

    Science.gov (United States)

    Smalling, Kelly L; Reilly, Timothy J; Sandstrom, Mark W; Kuivila, Kathryn M

    2013-03-01

    To document the environmental occurrence and persistence of fungicides, a robust and sensitive analytical method was used to measure 34 fungicides and an additional 57 current-use pesticides in bed sediments and suspended solids collected from areas of intense fungicide use within three geographic areas across the United States. Sampling sites were selected near or within agricultural research farms using prophylactic fungicides at rates and types typical of their geographic location. At least two fungicides were detected in 55% of the bed and 83% of the suspended solid samples and were detected in conjunction with herbicides and insecticides. Six fungicides were detected in all samples including pyraclostrobin (75%), boscalid (53%), chlorothalonil (41%) and zoxamide (22%). Pyraclostrobin, a strobilurin fungicide, used frequently in the United States on a variety of crops, was detected more frequently than p,p'-DDE, the primary degradate of p,p'-DDT, which is typically one of the most frequently occurring pesticides in sediments collected within highly agricultural areas. Maximum fungicide concentrations in bed sediments and suspended solids were 198 and 56.7 μg/kg dry weight, respectively. There is limited information on the occurrence, fate, and persistence of many fungicides in sediment and the environmental impacts are largely unknown. The results of this study indicate the importance of documenting the persistence of fungicides in the environment and the need for a better understanding of off-site transport mechanisms, particularly in areas where crops are grown that require frequent treatments to prevent fungal diseases. Published by Elsevier B.V.

  5. Impact of fungicides on weed growth

    Directory of Open Access Journals (Sweden)

    Nordmeyer, Henning

    2014-02-01

    Full Text Available The study has shown that fungicides influence the growth of weeds. The competition against crops will be substantially reduced. Bioassays in a climate chamber variation in temperature as well as different lightning phases and microplot trials under semi field levels were carried out to investigate the influence of fungicides on weed growth. Selected weed species (Alopecurus myosuroides, Viola arvensis, Galium aparine, Stellaria media, Lamium purpureum have been examined with different dose rates of fungicides (Adexar, Bravo 500, Diamant, Crupozin flüssig. Weed species showed a different sensitivity. There were leaf discoloration, contractions and growth inhibition. In some cases using common practise dose rates of fungicides more than 70% growth inhibition could be estimated 14 days after application in comparison to the untreated control. Effects were much stronger in bioassays than in semi field trials.

  6. Simulated minimum detectable activity concentration (MDAC) for a real-time UAV airborne radioactivity monitoring system with HPGe and LaBr_3 detectors

    International Nuclear Information System (INIS)

    Tang, Xiao-Bin; Meng, Jia; Wang, Peng; Cao, Ye; Huang, Xi; Wen, Liang-Sheng; Chen, Da

    2016-01-01

    An automatic real-time UAV airborne radioactivity monitoring system with high-purity germanium (HPGe) and lanthanum bromide (LaBr_3) detectors (NH-UAV) was developed to precisely obtain small-scope nuclide information in major nuclear accidents. The specific minimum detectable activity concentration (MDAC) calculation method for NH-UAV in the atmospheric environment was deduced in this study for a priori evaluation and quantification of the suitability of NH-UAV in the Fukushima nuclear accident, where the MDAC values of this new equipment were calculated based on Monte Carlo simulation. The effects of radioactive source term size and activity concentration on the MDAC values were analyzed to assess the detection performance of NH-UAV in more realistic environments. Finally, the MDAC values were calculated at different shielding thicknesses of the HPGe detector to improve the detection capabilities of the HPGe detector, and the relationship between the MDAC and the acquisition time of the system was deduced. The MDAC calculation method and data results in this study may be used as a reference for in-situ radioactivity measurement of NH-UAV. - Highlights: • A real-time UAV airborne radioactivity monitoring system (NH-UAV) was developed. • The efficiency calculations and MDAC values are given. • NH-UAV is able to monitor major nuclear accidents, such as the Fukushima accident. • The source term size can influence the detection sensitivity of the system. • The HPGe detector possesses measurement thresholds on activity concentration.

  7. Uncertainty and minimum detectable concentrations using relative, absolute and K*0-IAEA standardization for the INAA laboratory of the ETRR-2

    International Nuclear Information System (INIS)

    Khalil, M. Y.

    2006-01-01

    Full text: The Instrumental Neutron Activation Analysis (INAA) Laboratory of Egypt Second Training and Research Reactor (ETRR-2) is increasingly requested to perform multi-element analysis to large number of samples from different origins. The INAA laboratory has to demonstrate competence by conforming to appropriate internationally and nationally accepted standards. The objective of this work is to determine the uncertainty budget and sensitivity of the INAA laboratory measurements. Concentrations of 9 elements; Mn, Na, K, Ca, Co, Cr, Fe, Rb, and Cs, were measured against a certified test sample. Relative, absolute, and Ko-IAEA standardization methods were employed and results compared. The flux was monitored using cadmium covered gold method, and multifoil (gold, nickel and zirconium) method. The combined and expanded uncertainties were estimated. Uncertainty of concentrations ranged between 2-21% depending on the standardization method used. The relative method, giving the lowest uncertainty, produced uncertainty budget between 2 and 11%. The minimum detectable concentration was the lowest for Cs ranging between 0.36 and 0.59 ppb and the highest being for K in the range of 0.32 to 8.64 ppm

  8. Effect of fentanyl target-controlled infusions on isoflurane minimum anaesthetic concentration and cardiovascular function in red-tailed hawks (Buteo jamaicensis).

    Science.gov (United States)

    Pavez, Juan C; Hawkins, Michelle G; Pascoe, Peter J; Knych, Heather K DiMaio; Kass, Philip H

    2011-07-01

    To determine the impact of three different target plasma concentrations of fentanyl on the minimum anaesthetic concentration (MAC) for isoflurane in the red-tailed hawk and the effects on the haemodynamic profile. Experimental study. Six healthy adult red-tailed hawks (Buteo jamaicensis) of unknown sex with body weights (mean ± SD) of 1.21 ± 0.15 kg. This study was undertaken in two phases. In the first phase anaesthesia was induced with isoflurane in oxygen via facemask and maintained with isoflurane delivered in oxygen via a Bain circuit. Following instrumentation baseline determination of the MAC for isoflurane was made for each animal using the bracketing method and a supramaximal electrical stimulus. End-tidal isoflurane concentration (E'Iso) was then set at 0.75 × MAC and after an appropriate equilibration period a bolus of fentanyl (20 μg kg(-1)) was administered intravenously (IV) in order to determine the pharmacokinetics of fentanyl in the isoflurane-anaesthetized red-tailed hawk. During the second phase anaesthesia was induced in a similar manner and E'Iso was set at 0.75 × MAC for each individual. Fentanyl was infused IV to achieve target plasma concentrations between 8 and 32 ng mL(-1). At each fentanyl plasma concentration, the MAC for isoflurane and cardiovascular variables were determined. Data were analyzed by use of repeated-measures anova. Mean ± SD fentanyl plasma concentrations and isoflurane MACs were 0 ± 0, 8.51 ± 4, 14.85 ± 4.82 and 29.25 ± 11.52 ng mL(-1), and 2.05 ± 0.45%, 1.42 ± 0.53%, 1.14 ± 0.31% and 0.93 ± 0.32% for the target concentrations of 0, 8, 16 and 32 ng mL(-1), respectively. At these concentrations fentanyl significantly (p = 0.0016) decreased isoflurane MAC by 31%, 44% and 55%, respectively. Dose had no significant effect on heart rate, systolic, diastolic or mean arterial blood pressure. Fentanyl produced a dose-related decrease of isoflurane MAC with minimal effects on measured cardiovascular parameters in

  9. Effects of sub-minimum inhibitory concentrations of ciprofloxacin on enteroaggregative Escherichia coli and the role of the surface protein dispersin

    Energy Technology Data Exchange (ETDEWEB)

    Fowlkes, Jason Davidson [ORNL; Doktycz, Mitchel John [ORNL; Allison, David Post [ORNL

    2011-01-01

    Enteroaggregative Escherichia coli (EAEC) are bacterial pathogens that cause watery diarrhoea, which is often persistent and can be inflammatory. The antibiotic ciprofloxacin is used to treat EAEC infections, but a full understanding of the antimicrobial effects of ciprofloxacin is needed for more efficient treatment of bacterial infections. In this study, it was found that sub-minimum inhibitory concentrations (sub-MICs) of ciprofloxacin had an inhibitory effect on EAEC adhesion to glass and mammalian HEp-2 cells. It was also observed that bacterial surface properties play an important role in bacterial sensitivity to ciprofloxacin. In an EAEC mutant strain where the hydrophobic positively charged surface protein dispersin was absent, sensitivity to ciprofloxacin was reduced compared with the wild-type strain. Identified here are several antimicrobial effects of ciprofloxacin at sub-MIC concentrations indicating that bacterial surface hydrophobicity affects the response to ciprofloxacin. Investigating the effects of sub-MIC doses of antibiotics on targeted bacteria could help to further our understanding of bacterial pathogenicity and elucidate future antibiotic treatment modalities.

  10. Interaction between maropitant and carprofen on sparing of the minimum alveolar concentration for blunting adrenergic response (MAC-BAR) of sevoflurane in dogs.

    Science.gov (United States)

    Fukui, Sho; Ooyama, Norihiko; Tamura, Jun; Umar, Mohammed Ahmed; Ishizuka, Tomohito; Itami, Takaharu; Miyoshi, Kenjiro; Sano, Tadashi; Yamashita, Kazuto

    2017-03-18

    Maropitant, a neurokinin-1 receptor antagonist, may provide analgesic effects by blocking pharmacological action of substance P. Carprofen is a non-steroidal anti-inflammatory drug commonly used for pain control in dogs. The purpose of this study was to evaluate the effect of a combination of maropitant and carprofen on the minimum alveolar concentration for blunting adrenergic response (MAC-BAR) of sevoflurane in dogs. Six healthy adult beagle dogs were anesthetized with sevoflurane four times with a minimum of 7-day washout period. On each occasion, maropitant (1 mg/kg) alone, carprofen (4 mg/kg) alone, a combination of maropitant (1 mg/kg) and carprofen (4 mg/kg), or saline (0.1 ml/kg) was subcutaneously administered at 1 hr prior to the first electrical stimulation for the sevoflurane MAC-BAR determination. The sevoflurane MAC-BAR was significantly reduced by maropitant alone (2.88 ± 0.73%, P=0.010), carprofen alone (2.96 ± 0.38%, P=0.016) and the combination (2.81 ± 0.51%, P=0.0003), compared with saline (3.37 ± 0.56%). There was no significant difference in the percentage of MAC-BAR reductions between maropitant alone, carprofen alone and the combination. The administration of maropitant alone and carprofen alone produced clinically significant sparing effects on the sevoflurane MAC-BAR in dogs. However, the combination of maropitant and carprofen did not produce any additive effect on the sevoflurane MAC-BAR reduction. Anesthetic premedication with a combination of maropitant and carprofen may not provide any further sparing effect on anesthetic requirement in dogs.

  11. Occurrence of boscalid and other selected fungicides in surface water and groundwater in three targeted use areas in the United States.

    Science.gov (United States)

    Reilly, Timothy J; Smalling, Kelly L; Orlando, James L; Kuivila, Kathryn M

    2012-09-01

    To provide an assessment of the occurrence of fungicides in water resources, the US Geological Survey used a newly developed analytical method to measure 33 fungicides and an additional 57 current-use pesticides in water samples from streams, ponds, and shallow groundwater in areas of intense fungicide use within three geographic areas across the United States. Sampling sites were selected near or within farms using prophylactic fungicides at rates and types typical of their geographic location. At least one fungicide was detected in 75% of the surface waters and 58% of the groundwater wells sampled. Twelve fungicides were detected including boscalid (72%), azoxystrobin (51%), pyraclostrobin (40%), chlorothalonil (38%) and pyrimethanil (28%). Boscalid, a carboxamide fungicide registered for use in the US in 2003, was detected more frequently than atrazine and metolachlor, two herbicides that are typically the most frequently occurring pesticides in many large-scale water quality studies. Fungicide concentrations ranged from less than the method detection limit to approximately 2000 ngL(-1). Currently, limited toxicological data for non-target species exists and the environmental impacts are largely unknown. The results of this study indicate the importance of including fungicides in pesticide monitoring programs, particularly in areas where crops are grown that require frequent treatments to prevent fungal diseases. Published by Elsevier Ltd.

  12. Synthesis of Novel (E) -α-(methoxyimino) Benzeneacetate Derivatives and their Fungicidal Activities

    International Nuclear Information System (INIS)

    Wang, X.; Chen, P.; Pang, Y.; Zhao, Z.; Wu, G.; Wang, H.

    2015-01-01

    In order to find novel strobilurin derivatives with good fungicidal activities, a series of (E)-α-(methoxyimino)benzeneacetate analogues containing 1,2,4-triazole Schiff base moiety were designed and synthesized. Their structures were confirmed by IR,1H-NMR, HRMS or elemental analyses. The antifungal activities indicated that compounds 6 showed moderate to good fungicidal activities against Rhizoctonia solani, Botrytis cinereapers, Fusarium graminearum and Blumeria graminis at the concentration 50 μ g/mL. For example, compounds 6e and 6h exhibited promising antifungal activity against Rhizoctonia solani, Botrytis cinereapers and Fusarium graminearum. Compounds 6g and 6j had higher fungicidal activities against Blumeria graminis at the concentration of 50 μ g/ml, inhibitory rate is 95.32 percentage and 89.67 percentage, respectively. (author)

  13. Environmental fate of fungicides and other current-use pesticides in a central California estuary

    Science.gov (United States)

    Smalling, Kelly L.; Kuivila, Kathryn; Orlando, James L.; Phillips, Bryn M.; Anderson, Brian S.; Siegler, Katie; Hunt, John W.; Hamilton, Mary

    2013-01-01

    The current study documents the fate of current-use pesticides in an agriculturally-dominated central California coastal estuary by focusing on the occurrence in water, sediment and tissue of resident aquatic organisms. Three fungicides (azoxystrobin, boscalid, and pyraclostrobin), one herbicide (propyzamide) and two organophosphate insecticides (chlorpyrifos and diazinon) were detected frequently. Dissolved pesticide concentrations in the estuary corresponded to the timing of application while bed sediment pesticide concentrations correlated with the distance from potential sources. Fungicides and insecticides were detected frequently in fish and invertebrates collected near the mouth of the estuary and the contaminant profiles differed from the sediment and water collected. This is the first study to document the occurrence of many current-use pesticides, including fungicides, in tissue. Limited information is available on the uptake, accumulation and effects of current-use pesticides on non-target organisms. Additional data are needed to understand the impacts of pesticides, especially in small agriculturally-dominated estuaries.

  14. Resistance of Botrytis cinerea to fungicides controlling gray mold on strawberry in Brazil

    Directory of Open Access Journals (Sweden)

    Ueder Pedro Lopes

    Full Text Available ABSTRACT The aim of this study was to evaluate the resistance of Botrytis cinerea to the fungicides currently used for its control in Brazil. Isolates of the fungus were collected from different strawberry-producing fields in the states of Espírito Santo, Minas Gerais, and São Paulo, Brazil. First, a total of 183 isolates were identified at the species level using specific primers for the glyceraldehyde-3-phosphate dehydrogenase (G3PDH gene. The isolates were grown on potato dextrose agar (PDA containing the fungicides procymidone, iprodione, and thiophanate-methyl in different concentrations: 0.0 (control, 0.1; 1.0; 10.0; 100.0 and 1,000.0 μg∙mL−1. The percentage of mycelial growth inhibition was used to determine the effective concentration of the fungicide that was able to inhibit colony growth by 50% (EC50. Approximately 25.7% of the isolates were resistant to iprodione, 53.0% were resistant to procymidone, and 93.0% were resistant to thiophanate-methyl. Moreover, crossresistance and multiple resistance were verified, with 19.7% of the isolates showing resistance to 3 fungicides simultaneously. This finding explains the ineffectiveness of fungicides application to control gray mold in strawberry fields in Brazil and highlights the need for new strategies to manage this disease in the culture.

  15. Evaluation of some fungicides on mycorrhizal symbiosis between two Glomus species from commercial inocula and Allium porrum L. seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Dorrego, A.; Mestre Pares, J.

    2010-07-01

    This paper reports the effect of twenty-five commonly used fungicides in agriculture on two arbuscular mycorrhizal fungi (AMF) present in commercial products of ATENS, S.L.: Glomus intra radices (Schenck and Smith) and Glomus mosseae [(Nicol. and Gerd.) Gerdemann and Trappe], forming the symbiosis with leek plants. Systemic fungicides (Aliette, Beltanol, Caddy 10, Forum, Moncut, Ortiva, Previcur, Ridomil Gold MZ, Ridomil Gold SL, Rubigan, Sinthane, Stroby, Swich, Tachigarem, Teldor, Topas 10 EC, Frupica) and non systemic fungicides (Daconil 75%, Ditiver, Euparem, INACOP, Octagon, Parmex, Terrazole and Metaram), started to be applied to soil and leaves at recommended concentrations and frequencies 4 weeks after transplant and AMF inoculation. The effect of the fungicides was assessed by comparing treated and untreated plants that were inoculated with the AMF through quantification of root mycorrhizal colonization. Among the fungicides applied to the soil, Octagon, Ditiver, Parmex and Metaram virtually eliminated the mycorrhizal symbiosis in treated plants, while the mycorrhizal colonization was not affected by the soil treatment with Beltanol, INACOP and Previcur. Three fungicides of foliar recommended application: Rubigan, Frupica, and Sinthane, strongly inhibited mycorrhizal colonization, but Aliette, Forum, Teldor, Swich and Ortiva, did not seem to reduce it substantially. In addition, the work describes the individual effect of each fungicide applied on both, foliage and soil. (Author) 29 refs.

  16. Effects of triazole fungicides on androgenic disruption and CYP3A4 enzyme activity.

    Science.gov (United States)

    Lv, Xuan; Pan, Liumeng; Wang, Jiaying; Lu, Liping; Yan, Weilin; Zhu, Yanye; Xu, Yiwen; Guo, Ming; Zhuang, Shulin

    2017-03-01

    Triazole fungicides are widely used as broad-spectrum fungicides, non-steroidal antiestrogens and for various industrial applications. Their residues have been frequently detected in multiple environmental and human matrices. The increasingly reported toxicity incidents have led triazole fungicides as emerging contaminants of environmental and public health concern. However, whether triazole fungicides behave as endocrine disruptors by directly mimicking environmental androgens/antiandrogens or exerting potential androgenic disruption indirectly through the inhibition of cytochrome P450 (CYP450) enzyme activity is yet an unresolved question. We herein evaluated five commonly used triazole fungicides including bitertanol, hexaconazole, penconazole, tebuconazole and uniconazole for the androgenic and anti-androgenic activity using two-hybrid recombinant human androgen receptor (AR) yeast bioassay and comparatively evaluated their effects on enzymatic activity of CYP3A4 by P450-Glo™ CYP3A4 bioassay. All five fungicides showed moderate anti-androgenic activity toward human AR with the IC 50 ranging from 9.34 μM to 79.85 μM. The anti-androgenic activity remained no significant change after the metabolism mediated by human liver microsomes. These fungicides significantly inhibited the activity of CYP3A4 at the environmental relevant concentrations and the potency ranks as tebuconazole > uniconazole > hexaconazole > penconazole > bitertanol with the corresponding IC 50 of 0.81 μM, 0.93 μM, 1.27 μM, 2.22 μM, and 2.74 μM, respectively. We found that their anti-androgenic activity and the inhibition potency toward CYP3A4 inhibition was significantly correlated (R 2 between 0.83 and 0.97, p pesticides and structurally similar chemicals should fully consider potential androgenic disrupting effects and the influences on the activity of CYP450s. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. High minimum inhibitory concentration of imipenem as a predictor of fatal outcome in patients with carbapenem non-susceptible Klebsiella pneumoniae.

    Science.gov (United States)

    Wu, Ping-Feng; Chuang, Chien; Su, Chin-Fang; Lin, Yi-Tsung; Chan, Yu-Jiun; Wang, Fu-Der; Chuang, Yin-Ching; Siu, L Kristopher; Fung, Chang-Phone

    2016-09-02

    Carbapenem resistance in Klebsiella pneumoniae is important because of its increasing prevalence and limited therapeutic options. To investigate the clinical and microbiological characteristics of patients infected or colonized with carbapenem non-susceptible K. pneumoniae (CnsKP) in Taiwan, we conducted a retrospective study at Taipei Veterans General Hospital from January 2012 to November 2013. Carbapenem non-susceptibility was defined as a minimum inhibitory concentration (MIC) of ≥2 mg/L for imipenem or meropenem. A total of 105 cases with CnsKP were identified: 49 patients with infection and 56 patients with colonization. Thirty-one isolates had genes that encoded carbapenemases (29.5%), including K. pneumoniae carbapenemase (KPC)-2 (n = 27), KPC-3 (n = 1), VIM-1 (n = 1) and IMP-8 (n = 2). The in-hospital mortality among patients with CnsKP was 43.8%. A MIC for imipenem ≥16 μg/mL, nasogastric intubation and Acute Physiology and Chronic Health Evaluation II score were independent risk factors for in-hospital mortality for all patients with CnsKP. A MIC for imipenem ≥16 μg/mL was also an independent risk factor for 14-day mortality in patients with CnsKP. In conclusion, a positive culture for CnsKP was associated with high in-hospital mortality. A high imipenem MIC of CnsKP can predispose a patient to a poor prognosis.

  18. Effect of higher minimum inhibitory concentrations of quaternary ammonium compounds in clinical E. coli isolates on antibiotic susceptibilities and clinical outcomes.

    Science.gov (United States)

    Buffet-Bataillon, S; Branger, B; Cormier, M; Bonnaure-Mallet, M; Jolivet-Gougeon, A

    2011-10-01

    Quaternary ammonium compounds (QACs) are cationic surfactants used as preservatives and environmental disinfectants. Limited data are available regarding the effect of QACs in the clinical setting. We performed a prospective cohort study in 153 patients with Escherichia coli bacteraemia from February to September 2008 at University Hospital in Rennes. The minimum inhibitory concentrations (MICs) of antibiotics and QACs alkyldimethylbenzylammonium chloride (ADBAC) and didecyldimethylammonium chloride (DDAC) were determined by the agar dilution method. The capacity of biofilm production was assayed using the Crystal Violet method, and mutation frequencies by measuring the capacity of strains to generate resistance to rifampicin. Logistic regression analysis showed that one of the significant factors related to low MICs for ADBAC (≤16 mg/L) and DDAC (≤8 mg/L), was cotrimoxazole susceptibility (odds ratio: 3.72; 95% confidence interval: 1.22-11.24; P=0.02 and OR: 3.61; 95% CI: 1.56-7.56; PAntibiotic susceptibility to cotrimoxazole was strongly associated with susceptibility to amoxicillin and nalidixic acid (PE. coli isolates and antibiotic resistance. Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  19. Synthesis and fungicidal activity of pyrazole derivatives containing 1,2,3,4-tetrahydroquinoline.

    Science.gov (United States)

    Lei, Peng; Zhang, Xuebo; Xu, Yan; Xu, Gaofei; Liu, Xili; Yang, Xinling; Zhang, Xiaohe; Ling, Yun

    2016-01-01

    Take-all of wheat, caused by the soil-borne fungus Gaeumannomyces graminis var. tritici, is one of the most important and widespread root diseases. Given that take-all is still hard to control, it is necessary to develop new effective agrochemicals. Pyrazole derivatives have been often reported for their favorable bioactivities. In order to discover compounds with high fungicidal activity and simple structures, 1,2,3,4-tetrahydroquinoline, a biologically active group of natural products, was introduced to pyrazole structure. A series of pyrazole derivatives containing 1,2,3,4-tetrahydroquinoline were synthesized, and their fungicidal activities were evaluated. The bioassay results demonstrated that the title compounds displayed obvious fungicidal activities at a concentration of 50 μg/mL, especially against V. mali, S. sclerotiorum and G. graminis var. tritici. The inhibition rates of compounds 10d, 10e, 10h, 10i and 10j against G. graminis var. tritici were all above 90 %. Even at a lower concentration of 16.7 μg/mL, compounds 10d and 10e exhibited satisfied activities of 100 % and 94.0 %, respectively. It is comparable to that of the positive control pyraclostrobin with 100 % inhibition rate. A series of pyrazole derivatives containing 1,2,3,4-tetrahydroquinoline were synthesized and their structures were confirmed by (1)H NMR, (13)C NMR, IR spectrum and HRMS or elemental analysis. The crystal structure of compound 10g was confirmed by X-ray diffraction. Bioassay results indicated that all title compounds exhibited obvious fungicidal activities. In particular, compounds 10d and 10e showed comparable activities against G. graminis var. tritici with the commercial fungicide pyraclostrobin at the concentration of 16.7 μg/mL.Graphical abstractA series of pyrazole derivatives containing 1,2,3,4-tetrahydroquinoline were designed and synthesized. Bioassay results indicated that all these compounds exhibited obvious fungicidal activities.

  20. FUNGICIDAL PROPERTIES OF ARTEMISIA AROMATIC PLANTS TOWARDS FUSARIUM OXYSPORUM

    Directory of Open Access Journals (Sweden)

    Ivashchenko Iryna Vіctorovna

    2015-08-01

    Full Text Available The article establishes the fungicidal activity of water extracts of Artemisia maritimа L., Artemisia austriaca Jacq., under the concentration of 100, 50 and 25 mg/ml on dry matter with regard to the phytopathogenic mushroom Fusarium oxysporum. It also shows the fungistatic influence of extract of Artemisia dracunculus L. under concentration 25 and 50 mg/ml, fungicidal – under 100 mg/ml. Concerning Artemisia abrotanum L., the slow growth of mushroom is observed under the concentration 25 mg/ml, fungicidal effect – under 50 and 100 mg/ml. The paper provides the information on the component composition of ethereal oil and phenolic compounds of Artemisia maritimа, Artemisia austriaca, Artemisia abrotanum, Artemisia dracunculus, cultivated in Zhytomyr Polissya. The chief ingredients of ethereal oil which is synthesized by the plant of Artemisia abrotanum are 1,8-cineole (30.44% and camphor (31.92%. A high 1,8-cineole and camphor content determines antimicrobial properties of the plants. Amount of phenolic compounds in the air-dry raw Artemisia abrotanum is 2.98 percent. By the method of highly efficient solution chromatography (HESChr in the grass of Artemisia abrotanum we have detected 23 phenolic compounds, of which we identified such flavonoids as rutin, luteolin-7-glycoside as well as caffeic, chlorogenic and isochlorogenic acids. The main compounds of ethereal oil of Artemisia austriaca are trans-verbenole (30.77 %, pinocarvone (10.77 % and sabinilacetate (18.16 %. In the grass of Artemisia austriaca we have detected 31 phenolic compounds, of which we identified such flavonoids as rutin, apigenin, quercetin-bioside and the following acids: caffeic, chlorogenic, and isochlorogenic. Amount of phenolic compounds in the air-dry raw Austrian wormwood is 27.25 mg / g (2.73 %. The main component of ethereal oil of Artemisia dracunculus is methyleugenol (94.65 %. We have discovered 31 phenolic compounds in the grass of linear-leaved wormwood

  1. Control Efficacy of Fungicides on Chinese Cabbage Clubroot under Several Conditions

    Directory of Open Access Journals (Sweden)

    Min-Yong Eom

    2011-08-01

    Full Text Available To develop the efficient screening methods for antifungal compound active to Chinese cabbage clubroot caused by Plasmodiophora brassicae, the control efficacy of three fungicides fluazinam, ethaboxam, and cyazofamid on the disease was tested under several conditions such as soil types, cultivars of Chinese cabbage, growth stages of the host, and inoculum concentrations. The in vivo antifungal activities of the fungicides on clubroot of two Chinese cabbage cultivars were hardly different. At 7- and 14-day-old seedlings, the fungicides were more effective to control of clubroot than at 21-day-old seedlings. In a commercial horticulture media soil (CNS, disease severity of untreated controls was higher and control activity of the fungicides was less than in a mixture of CNS and upland soil (1:1, v/v. Disease development of the seedlings inoculated with P. brassicae at 1.8×10(7 spores/pot to 1.1×10(9 spores/pot was almost same, but control efficacy of the fungicides was negatively correlated with inoculum dosages. To effectively select in vivo antifungal compound on Chinese cabbage clubroot, 14-day-old seedlings need to be inoculated with P. brassicae by drenching the spore suspension to give 1×10(8 spores/pot 1 day after chemical treatment. To develop clubroot, the inoculated plants are incubated in a growth chamber at 20℃ for 2 days, and then cultivated in a greenhouse (20±5℃ for four weeks.

  2. Effectiveness of Different Classes of Fungicides on Botrytis cinerea Causing Gray Mold on Fruit and Vegetables

    Directory of Open Access Journals (Sweden)

    Joon-Oh Kim

    2016-12-01

    Full Text Available Botrytis cinerea is a necrotrophic pathogen causing a major problem in the export and post-harvest of strawberries. Inappropriate use of fungicides leads to resistance among fungal pathogens. Therefore, it is necessary to evaluate the sensitivity of B. cinerea to various classes of fungicide and to determine the effectiveness of different concentrations of commonly used fungicides. We thus evaluated the effectiveness of six classes of fungicide in inhibiting the growth and development of this pathogen, namely, fludioxonil, iprodione, pyrimethanil, tebuconazole, fenpyrazamine, and boscalid. Fludioxonil was the most effective (EC₅₀ < 0.1 μg/ml, and pyrimethanil was the least effective (EC₅₀ = 50 μg/ml, at inhibiting the mycelial growth of B. cinerea. Fenpyrazamine and pyrimethanil showed relatively low effectiveness in inhibiting the germination and conidial production of B. cinerea. Our results are useful for the management of B. cinerea and as a basis for monitoring the sensitivity of B. cinerea strains to fungicides.

  3. Effects of 2 fungicide formulations on microbial and macroinvertebrate leaf decomposition under laboratory conditions

    Science.gov (United States)

    Elskus, Adria; Smalling, Kelly L.; Hladik, Michelle; Kuivila, Kathryn

    2016-01-01

    Aquatic fungi contribute significantly to the decomposition of leaves in streams, a key ecosystem service. However, little is known about the effects of fungicides on aquatic fungi and macroinvertebrates involved with leaf decomposition. Red maple (Acer rubrum) leaves were conditioned in a stream to acquire microbes (bacteria and fungi), or leached in tap water (unconditioned) to simulate potential reduction of microbial biomass by fungicides. Conditioned leaves were exposed to fungicide formulations QUILT (azoxystrobin + propiconazole) or PRISTINE (boscalid + pyraclostrobin), in the presence and absence of the leaf shredder, Hyalella azteca (amphipods; 7-d old at start of exposures) for 14 d at 23 °C. QUILT formulation (~ 0.3 μg/L, 1.8 μg/L, 8 μg/L) tended to increase leaf decomposition by amphipods (not significant) without a concomitant increase in amphipod biomass, indicating potential increased consumption of leaves with reduced nutritional value. PRISTINE formulation (~ 33 μg/L) significantly reduced amphipod growth and biomass (p<0.05), effects similar to those observed with unconditioned controls. The significant suppressive effects of PRISTINE on amphipod growth, and the trend towards increased leaf decomposition with increasing QUILT concentration, indicate the potential for altered leaf decay in streams exposed to fungicides. Further work is needed to evaluate fungicide effects on leaf decomposition under conditions relevant to stream ecosystems, including temperature shifts and pulsed exposures to pesticide mixtures.

  4. O mínimo de oxigênio na costa leste do Brasil entre 7-22ºS The minimum oxygen concentration in easthern Brasilian coast between 7-22ºS

    Directory of Open Access Journals (Sweden)

    Argeo Magliocca

    1978-01-01

    Full Text Available In the South Atlantic nearly the Brazilian coast, at low latitudes, the layer of minimum oxygen concentration shows distinct values between the Equatorial region (7ºS and the region limited by latitudes of 18-22ºS. In the vicinity of the Equator the minimum concentration is remarkably clear (2,0 ml/l at 7ºS and at 22ºS the minima values raise up to 4.0-4.5 ml/l. The minimum oxygen layer follows the isopynics surfaces (σt = 26.8-27.2 in depths of 300-400 m (7ºS and 600-800 m (22ºS . The oxygen concentration in this area results from a biochemical and physical processes, due to the presence of poor water Brazil Current southward and the rich one Intermediate Antartic water flowing northward.

  5. Occurrence and Environmental Effects of Boscalid and Other Fungicides in Three Targeted Use Areas in the United States

    Science.gov (United States)

    Reilly, T. J.; Smalling, K. L.; Wilson, E. R.

    2011-12-01

    Fungicides are typically used to control the outbreak of persistent, historically significant plant diseases like late blight (caused by Phytophthora infestans and responsible for the Irish Potato famine of 1846) and newer plant diseases like Asian Soy Rust, both of which are potentially devastating if not controlled. Of the more than 67,000 pesticide products currently registered for use in the United States, over 3,600 are used to combat fungal diseases. Although they are widely used, relatively little is known about the fate and potential secondary effects of fungicides in the aquatic environment. Even less is known about the fate and environmental occurrence of recently registered fungicides including boscalid, which was first registered for use in the US in 2003. Unlike most other pesticides, multiple fungicides are typically applied as a prophylactic crop protectant upwards of ten times per season (depending upon conditions and crop type), but at lower application rates than herbicides or insecticides. This difference in usage increases the likelihood of chronic exposure of aquatic ecosystems to low concentrations of fungicides. Using a newly developed analytical method, the U.S. Geological Survey measured 33 fungicides in surface water and shallow groundwater in three geographic areas of intense fungicide use across the US. Sampling sites were selected near or within farms using prophylactic fungicides at rates and types typical of the crop type and their geographic location. At least one fungicide was detected in 75% of the surface waters (n=60) and 58% of the groundwater (n=12) samples. Twelve fungicides were detected in surface- and groundwater including boscalid (72%), azoxystrobin (51%), pyraclostrobin (40%), chlorothalonil (38%) and pyrimethanil (28%). Boscalid was the most frequently detected pesticide and has not been previously documented in the aquatic environment. In this study, an average of 44% of the pesticide concentration in a water sample

  6. Effect of fungicides on Wyoming big sagebrush seed germination

    Science.gov (United States)

    Robert D. Cox; Lance H. Kosberg; Nancy L. Shaw; Stuart P. Hardegree

    2011-01-01

    Germination tests of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young [Asteraceae]) seeds often exhibit fungal contamination, but the use of fungicides should be avoided because fungicides may artificially inhibit germination. We tested the effect of seed-applied fungicides on germination of Wyoming big sagebrush at 2 different...

  7. Synthesis and fungicidal properties of 2,4-diaza-1,3,5 ...

    African Journals Online (AJOL)

    The preparation of 2,4-diaza-1,3,5-pentanetrione compounds were described. The fungicidal effects of these compounds on the mycelial growth of the isolate, Phoma eupyrena were carried out by in vitro experiment. The results show that the response to treatment depended not only on the concentration of the compounds ...

  8. Effects of oral exposure to fungicides on honey bee nutrition and immunity

    Science.gov (United States)

    Worker bees fed pollen containing fungicides (boscalid and pyraclostrobin) that are respiratory inhibitors had lower ATP concentrations in thoracic muscle tissue than those fed untreated pollen in both cage and colony studies. Midgut protease activity, used an indicator of consumption, was higher in...

  9. Effects of artea, a systemic fungicide, on the antioxidant system and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-09-01

    Sep 1, 2009 ... from oxygen metabolism in mitochondria (Alscher et al.,. 2002). Plants have well ... effects on plant in the sense they may induce a decrease in growth as well as modulating the metabolic balance. Morphological effects of ... with fungicide concentration (about 150% at 100 ppm). At. 25 ppm, the increase in ...

  10. Assessing effects of the fungicide tebuconazole to heterotrophic microbes in aquatic microcosms

    NARCIS (Netherlands)

    Dimitrov, M.R.; Kosol, Sujitra; Smidt, H.; Brink, van den P.J.; Wijngaarden, van R.P.A.; Brock, T.C.M.; Maltby, L.

    2014-01-01

    Aquatic ecological risk assessment of fungicides in Europe under Regulation 1107/2009/EC does not currently assess risk to non-target bacteria and fungi. Rather, regulatory acceptable concentrations based on ecotoxicological data obtained from studies with fish, invertebrates and primary producers

  11. Factors influencing the toxicity of Headline® fungicides to terrestrial stage toads.

    Science.gov (United States)

    Cusaac, J Patrick W; Mimbs, William H; Belden, Jason B; Smith, Loren M; McMurry, Scott T

    2017-10-01

    Amphibians are susceptible to exposure from contaminants via multiple pathways. Pyraclostrobin fungicides have been shown to be toxic to terrestrial amphibians at environmentally relevant concentrations; however, these studies did not account for factors that may influence exposure and effects, such as fungicide formulation, age of the individual, exposure route, and physiological state of the individual. We examined Headline® and Headline AMP® fungicide toxicity to adult Anaxyrus cognatus and Anaxyrus woodhousii by direct overspray, as well as acute toxicity of Headline AMP to juvenile A. cognatus through direct overspray, previously exposed soils, and diet. We also assessed effects of hydration state on fungicide toxicity in juvenile A. cognatus and sublethal effects of fungicide exposure on prey-orientation ability of juvenile A. cognatus. Neither formulation of Headline caused mortality of adult A. cognatus and A. woodhousii at up to 5 times the maximum label rate in North American corn (1052 and 879 mL formulation/ha for Headline AMP and Headline fungicides, respectively, corresponding to 1.52 and 2.2 μg pyraclostrobin/cm 2 , respectively). Exposures of juvenile A. cognatus to Headline AMP via direct overspray and previously exposed soils (2 types) resulted in median lethal rate (LR50) values of 2.4, 3.34, and 3.61 μg pyraclostrobin/cm 2 , respectively. Dietary Headline AMP exposure was not toxic, prey-orientations were not influenced by exposure, and effects were similar between dehydrated and hydrated treatments (LR50 = 2.4 and 2.3 μg pyraclostrobin/cm 2 , respectively). These results, combined with exposure concentrations reported in previous studies, suggest that risk of acute mortality for amphibians in terrestrial environments is low and is dictated by body size and site-specific factors influencing exposure. Environ Toxicol Chem 2017;36:2679-2688. © 2017 SETAC. © 2017 SETAC.

  12. Isolation of Stem rot Disease Causing Organism of Brinjal and their in-vitro Inhibition with Fungicides and Bio-control Agents

    Directory of Open Access Journals (Sweden)

    Shaily Javeria

    2014-09-01

    Full Text Available Different strains of Sclerotinia sclerotiorum were isolated from the diseased samples collected from different hosts and locations. Among the 14 isolates, 12 isolates colonies covered the entire Petri plates within 96 hours but, two isolates from fababean and yellow mustard showed slow colony growth within 96 hours. All isolates produced sclerotia which were varied in number, but the fenugreek isolate produced maximum (43 number of sclerotia and lambs quarter isolate produced minimum number of sclerotia (12 on PDA medium. To examine inhibitory effect of fungicide on the mycelial growth of the pathogen, 9 fungicides were tested in vitro against Sclerotinia sclerotiorum, of those carbendazim, carboxin, topsin-M and carbendazim+ mancozeb (SAAF were found most effective and inhibited the mycelial growth of pathogen up to 100 per cent at 0.05%, 0.1%, and 0.2% concentration. The effect of different bioagents viz., Trichoderma harzianum, T. viride, T. koningii, T. atroviride, T. longibraciatum, Aspergillus niger, Chaetomium globosome and Penicillium notatum in inhibiting the growth of Sclerotinia sclerotiorum was studied through “Dual Culture Technique”. The data showed that among the eight biocontrol agent six were fond effective. The maximum inhibition was found by T. harzianum causing 70.82% inhibition of mycelial growth of the pathogen S. sclerotiorum.

  13. Regression analysis and categorical agreement of fluconazole disk zone diameters and minimum inhibitory concentration by broth microdilution of clinical isolates of Candida.

    Science.gov (United States)

    Aggarwal, P; Kashyap, B

    2017-06-01

    Rampant use of fluconazole in Candida infections has led to predominance of less susceptible non-albicans Candida over Candida albicans. The aim of the study was to determine if zone diameters around fluconazole disk can be used to estimate the minimum inhibitory concentration (MIC) for clinical isolates of Candida species and vice versa. Categorical agreement between the Clinical & Laboratory Standards Institute (CLSI) recommended disk diffusion and CLSI broth microdilution method was sought for. Antifungal susceptibility testing by disk diffusion and Broth microdilution was done as per CLSI document M44-S3 and CLSI document M27-S4 for Candida isolates respectively. Regression analysis correlating zone diameters to MIC value was done. Pearson's correlation coefficient was calculated to determine correlation between disk zone diameters and MICs. Candida albicans (33.3%) was clearly outnumbered by other non-albicans species predominantly Candida tropicalis (42.5%) and Candida glabrata (18.4%). Ten percent of the strains were resistant to fluconazole by disk diffusion and 13% by broth microdilution. MIC range for Candida albicans and Candida tropicalis ranged from≤0.25-64μg/ml while that of Candida glabrata ranged from≤0.25-128μg/ml. Categorical agreement between disk diffusion and broth microdilution was 86.8%. Pearson's coefficient of correlation was -0.5975 indicating moderate negative correlation between the two variables. Zone sizes can be used to estimate the MIC values, although with limited accuracy. There should be a constant effort to upgrade the guidelines in view of new clinical data, and laboratories should make an active effort to incorporate them. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  14. An investigation of vancomycin minimum inhibitory concentration creep among methicillin-resistant Staphylococcus aureus strains isolated from pediatric patients and healthy children in Northern Taiwan.

    Science.gov (United States)

    Chang, Chia-Ning; Lo, Wen-Tsung; Chan, Ming-Chin; Yu, Ching-Mei; Wang, Chih-Chien

    2017-06-01

    The phenomenon of vancomycin minimum inhibitory concentration (MIC) creep is an increasingly serious problem in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. In this study, we investigated the vancomycin and daptomycin MIC values of MRSA strains isolated from pediatric patients and MRSA colonized healthy children. Then, we assessed whether there was evidence of clonal dissemination for strains with an MIC to vancomycin of ≥ 1.5 μg/mL. We collected clinical MRSA isolates from pediatric patients and from healthy children colonized with MRSA during 2008-2012 at a tertiary medical center in northern Taiwan and obtained vancomycin and daptomycin MIC values using the Etest method. Pulse-field gel electrophoresis (PFGE) and staphylococcal cassette chromosome (SCCmec) typing were used to assess clonal dissemination for strains with an MIC to vancomycin of ≥ 1.5 μg/mL. A total 195 MRSA strains were included in this study; 87 were isolated patients with a clinical MRSA infection, and the other 108 strains from nasally colonized healthy children. Vancomycin MIC≥1.5 μg/mL was seen in more clinical isolates (60/87, 69%) than colonized isolates (32/108, 29.6%), p < 0.001. The PFGE typing of both strains revealed multiple pulsotypes. Vancomycin MIC creeps existed in both clinical MRSA isolates and colonized MRSA strains. Great diversity of PFGE typing was in both strains collected. There was no association between the clinical and colonized MRSA isolates with vancomycin MIC creep. Copyright © 2016. Published by Elsevier B.V.

  15. Is Low Efficacy of Fungicides always a Consequence of Fungicide Resistance Development in Pathogen Populations?

    Directory of Open Access Journals (Sweden)

    Brankica Tanović

    2011-01-01

    Full Text Available Efficacy of four fungicides with different modes of action (vinclozolin, pyrimethanil, benomyland fenhexamid in control of B. cinerea in raspberry, was investigated in the paper.The trials were conducted at two localities in commercial raspberry plantations. In the caseof unsatisfactory fungicide efficacy, qualitative and/or quantitative test of the susceptibilityof the isolates to particular fungicide was performed, to determine whether the low efficacyis a consequence of resistance development in the pathogen population. At both localities,pyrimethanil and fenhexamid demonstrated the highest efficacy (73.2-89.6%, whilethe efficacy of vinclozolin was statistically significantly lower (48.7-63.4% at both localities.However, qualitative and quantitative test of susceptibility to vinclozolin showed that all theisolates were susceptible to vinclozolin and that the reason for unsatisfactory efficacy shouldbe primarily sought in inadequate fungicide application

  16. Screening Phytophthora rubi for fungicide resistance

    Science.gov (United States)

    Preliminary results from the survey for fungicide resistance in Phytophthora were reported at the 2016 Washington Small Fruit Conference. Phytophthora was isolated from diseased plants in 28 red raspberry fields and tested against mefenoxam, the active ingredient of Ridomil. Most isolates were ident...

  17. Insecticidal and fungicidal compounds from Isatis tinctoria.

    Science.gov (United States)

    Seifert, K; Unger, W

    1994-01-01

    Tryptanthrin (1), indole-3-acetonitrile (2) and p-coumaric acid methylester (3) were isolated from the aerial parts of Isatis tinctoria L. The compounds show insecticidal and anti-feedant activity against termites (Reticulitermis santonensis), insect preventive and control activity against larvae of the house longhorn beetle (Hylotrupes bajulus) and fungicidal activity against the brown-rot fungus (Coniophora puteana).

  18. SYNTHESIS AND FUNGICIDAL ACTIVITY OF ACETYL ...

    African Journals Online (AJOL)

    a

    large varieties of new sulfur based crop protection chemicals in development around the world. [14, 15]. Methods ... sulfur fission viz, the resonance – stabilized benzyl (or isomeric tropylium) cation [19]. The elimination of ... two well – established fungicides so as to compare their activities with those of compounds 1(a. – d).

  19. Potential of Cerbera odollam as a bio-fungicide for post-harvest pathogen Penicilium digitatum

    Science.gov (United States)

    Singh, Harbant; Yin-Chu, Sue; Al-Samarrai, Ghassan; Syarhabil, Muhammad

    2015-05-01

    Postharvest diseases due to fungal infection contribute to economic losses in agriculture industry during storage, transportation or in the market. Penicillium digitatum is one of the common pathogen responsible for the postharvest rot in fruits. This disease is currently being controlled by synthetic fungicides such as Guazatine and Imazalil. However, heavy use of fungicides has resulted in environmental pollution, such as residue in fruit that expose a significant risk to human health. Therefore, there is a strong need to develop alternatives to synthetic fungicide to raise customer confidence. In the current research, different concentrations (500 to 3000 ppm) of ethanol extract of Cerbera odollam or commonly known as Pong-pong were compared with Neem and the controls (Positive control/Guazatine; Negative control/DMSO) for the anti-fungicide activity in PDA media contained in 10 cm diameter Petri dishes, using a modification of Ruch and Worf's method. The toxicity (Lc50) of the C.odollam extract was determined by Brine-shrimp test (BST). The results of the research indicated that crude extraction from C.odollam showed the highest inhibition rate (93%) and smallest colony diameter (0.63 cm) at 3000 ppm in vitro compared with Neem (inhibition rate: 88%; colony diameter: 1.33 cm) and control (Positive control/Guazatine inhibition rate: 79%, colony diameter: 1.9 cm; Negative control/DMSO inhibition rate: 0%, colony diameter: 9.2 cm). C.odollam recorded Lc50 value of 5 µg/ml which is safe but to be used with caution (unsafe level: below 2 µg/ml). The above anti-microbial activity and toxicity value results indicate that C.odollam has a potential of being a future bio-fungicide that could be employed as an alternative to synthetic fungicide.

  20. Sertraline demonstrates fungicidal activity in vitro for Coccidioides immitis

    Directory of Open Access Journals (Sweden)

    Simon Paul

    2016-07-01

    Full Text Available Coccidioidomycosis causes substantial morbidity in endemic areas. Disseminated coccidioidomycosis is an AIDS defining condition and treatment often requires lifelong antifungal therapy. Sertraline, a widely used serotonin-reuptake inhibitor anti-depressant, has demonstrated activity against Candida and Cryptococcus sp. both in vitro and in vivo. To evaluate if sertraline has activity against Coccidioides, the minimal inhibitory concentration (MIC and minimal fungicidal concentration (MFC of sertraline for four clinical isolates of C. immitis were determined. Sertraline was observed to have an MIC range of 4–8 µg/ml and MFC also of 4–8 µg/ml for Coccidioides. These MIC and MFC results for C. immitis are similar to those reported for Cryptococcus sp. suggesting sertraline may potentially have utility for the treatment of coccidioidomycosis.

  1. Differences in sensitivity between earthworms and enchytraeids exposed to two commercial fungicides.

    Science.gov (United States)

    Bart, Sylvain; Laurent, Céline; Péry, Alexandre R R; Mougin, Christian; Pelosi, Céline

    2017-06-01

    The use of pesticides in crop fields may have negative effects on soil Oligochaeta Annelida, i.e., earthworms and enchytraeids, and thus affect soil quality. The aim of this study was to assess the effects of two commercial fungicide formulations on the earthworm Aporrectodea caliginosa and the enchytraeid Enchytraeus albidus in a natural soil. The fungicides were Cuprafor micro® (copper oxychloride), commonly used in organic farming, and Swing Gold® (epoxiconazole and dimoxystrobin), a synthetic fungicide widely used in conventional farming to protect cereal crops. Laboratory experiments were used to assess the survival, biomass loss and avoidance behaviour. No lethal effect was observed following exposure to the copper fungicide for 14 days, even at 5000mgkg -1 of copper, i.e. 650 times the recommended dose (RD). However, a significant decrease in biomass was observed from 50mgkg -1 of copper (6.5 times the RD) for A. caliginosa and at 5000mgkg -1 of copper (650 times the RD) for E. albidus. These sublethal effects suggest that a longer period of exposure would probably have led to lethal effects. The EC50 avoidance for the copper fungicide was estimated to be 51.2mgkg -1 of copper (6.7 times the RD) for A. caliginosa, and 393mgkg -1 of copper (51 times the RD) for E. albidus. For the Swing Gold® fungicide, the estimated LC50 was 7.0 10 -3 mLkg -1 (6.3 times the RD) for A. caliginosa and 12.7 10 -3 mLkg -1 (11.0 times the RD) for E. albidus. No effect on biomass or avoidance was observed at sublethal concentrations of this synthetic fungicide. It was concluded that enchytraeids were less sensitive than earthworms to the two commercial fungicides in terms of mortality, biomass loss and avoidance behaviour. Therefore we discuss the different strategies possibly used by the two Oligochaeta species to cope with the presence of the pesticides were discussed, along with the potential consequences on the soil functions. Copyright © 2017 Elsevier Inc. All rights

  2. Aggregative stability of fungicidal nanomodifier based on zinc hydrosilicates

    Science.gov (United States)

    Grishina, Anna; Korolev, Evgeniy

    2018-03-01

    Currently, there is a strong need of high performance multi functional materials in high-rise construction. Obviously, such materials should be characterized by high strength; but for interior rooms biosafety is important as well. The promising direction to obtain both high strength and maintain biosafety in buildings and structures is to manage the structure of mineral binders by means of fungicidal nanomodifier based on zinc hydrosilicates. In the present work the aggregative stability of colloidal solutions of zinc hydrosilicates after one year of storage was studied. It has been established that the concentration of iron (III) hydroxide used to prepare the precursor of zinc hydrosilicates has a significant effect on the long-term aggregative stability: as the concentration of iron (III) hydroxide increases, the resistance of the fungicidal nanomodifier increases. It was found that, despite the minimal concentration of nano-sized zinc hydrosilicates (0.028%), the colloidal solution possesses a low long-term aggregative stability; while in the initial period (not less than 14 days) the colloidal solution of the nanomodifier is aggregatively stable. It is shown that when the ratio in the colloidal solution of the amount of the substance CH3COOH / SiO2 = 0.43 is reached, an increase in the polymerization rate is observed, which is the main cause of low aggregative stability. Colloidal solutions containing zinc hydrosilicates synthesized at a concentration of iron (III) hydroxide used to produce a precursor equal to 0.7% have a long-term aggregative stability and do not significantly change the reduced particle. Such compositions are to be expediently used for the nanomodifying of building composites in order to control their structure formation and to create conditions that impede the development of various mycelial fungi.

  3. Rust Inhibitor And Fungicide For Cooling Systems

    Science.gov (United States)

    Adams, James F.; Greer, D. Clay

    1988-01-01

    Mixture of benzotriazole, benzoic acid, and fungicide prevents growth of rust and fungus. Water-based cooling mixture made from readily available materials prevents formation of metallic oxides and growth of fungi in metallic pipes. Coolant remains clear and does not develop thick sludge tending to collect in low points in cooling systems with many commercial rust inhibitors. Coolant compatible with iron, copper, aluminum, and stainless steel. Cannot be used with cadmium or cadmium-plated pipes.

  4. Management of Anthracnose in Soybean using Fungicide

    Directory of Open Access Journals (Sweden)

    Subash Subedi

    2015-12-01

    Full Text Available Experiments on soybean (Glycine max L. Meril were carried out aiming to control anthracnose (pod blight caused by fungus, Colletotrichum truncatum with five treatments represented by different fungicidal sprays against control receiving no spray with three replicates of each under field conditions during two consecutive years from 2012 to 2013. In 2012, the higher Percent Disease Control (PDC and Percent Yield Increase (PYI were estimated in plot treated with SAAF (Carbendazim 12% + Mancozeb 63% followed by Mancozeb fungicides. The mean Pod Infection (PI was low in plots treated with SAAF followed by Mancozeb. Almost similar trends of disease control were observed in 2013. The lower Percent Disease Index (PDI was 46.25% and mean PI was 29.67% with higher yield value of 2431.25 kg/ha obtained from the plots sprayed with SAAF then by Mancozeb. The results showed that, the combined treatment with fungicides, SAAF followed by Mancozeb were effective to control anthracnose or pod blight disease of soybean to increase the yield.

  5. The fungicidal properties of the carbon materials obtained from chitin and chitosan promoted by copper salts

    Energy Technology Data Exchange (ETDEWEB)

    Ilnicka, Anna, E-mail: annakucinska@o2.pl; Walczyk, Mariusz; Lukaszewicz, Jerzy P.

    2015-07-01

    Renewable raw materials chitin and chitosan (N-deacetylated derivative of chitin) were subjected to action of different copper modifiers that were carbonized in the atmosphere of the N{sub 2} inert gas. As a result of the novel manufacturing procedure, a series of carbon materials was obtained with developed surface area and containing copper derivatives of differentiated form, size, and dispersion. The copper modifier and manufacturing procedure (concentration, carbonization temperature) influence the physical–chemical and fungicide properties of the carbons. The received carbons were chemically characterized using several methods like low-temperature adsorption of nitrogen, X-ray diffraction analysis, scanning electron microscopy, cyclic voltammetry, elemental analysis, and bioassay. Besides chemical testing, some biological tests were performed and let to select carbons with the highest fungicidal activity. Such carbons were characteristic of the specific form of copper derivatives occurring in them, i.e., nanocrystallites of Cu{sup 0} and/or Cu{sub 2}O of high dispersion on the surface of carbon. The carbons may find an application as effective contact fungistatic agents in cosmetology, medicine, food industry, etc. - Highlights: • The novel manufacturing procedure yields new functional carbon materials. • Two biopolymers chitin and chitosan can undergo copper(II) ion modification. • The Cu-modified carbon materials exhibit high fungicidal activity. • The fungicidal activity results from the presence of Cu{sup 0} and Cu{sub 2}O nano-crystallites.

  6. In vitro sensitivity reduction of Fusarium graminearum to DMI and QoI fungicides

    Directory of Open Access Journals (Sweden)

    Aveline Avozani

    2014-12-01

    Full Text Available In Brazil, Fusarium head blight (FHB affecting wheat can cause up to 39.8% damage. Resistant cultivars are not available yet; thus, short-term disease control relies on the use of fungicides. The first step to improve control is to monitor fungal populations that are sensitivity to chemicals in order to achieve efficient FHB management. In vitro experiments were conducted to evaluate the inhibitory concentration (IC50 of fungicides for both mycelial growth and conidial germination of ten Fusarium graminearum isolates. The following demethylation inhibitor (DMI fungicides were tested: metconazole, prothioconazole and tebuconazole. In addition, pyraclostrobin and trifloxystrobin were included, representing QoI fungicides, as well as three co-formulations containing metconazole + pyraclostrobin, prothioconazole + trifloxystrobin, and tebuconazole + trifloxystrobin. For mycelial growth, the overall mean IC50 of isolates was: metconazole 0.07, prothioconazole 0.1, and tebuconazole 0.19 mg/L. For the co-formulations, it was: prothioconazole + trifloxystrobin 0.08, tebuconazole + trifloxystrobin 0.12, and metconazole + pyraclostrobin 0.14 mg/L. Regarding spore germination inhibition, IC50 for prothioconazole + trifloxystrobin was 0.06, for tebuconazole + trifloxystrobin, 0.12 mg/L, for QoI alone pyraclostrobin, was 0.09, and for trifloxystrobin, 0.28 mg/L. There was a sensitivity shift among isolates and the highest fungitoxicity to F. graminearum was confirmed for prothioconazole, metconazole and tebuconazole .

  7. Phenotypical and Molecular Characterisation of Fusarium circinatum: Correlation with Virulence and Fungicide Sensitivity

    Directory of Open Access Journals (Sweden)

    Martin Mullett

    2017-11-01

    Full Text Available Fusarium circinatum, causing pine pitch canker, is one of the most damaging pathogens of Pinus species. This study investigated the use of phenotypical and molecular characteristics to delineate groups in a worldwide collection of isolates. The groups correlated with virulence and fungicide sensitivity, which were tested in a subset of isolates. Virulence tests of twenty isolates on P. radiata, P. sylvestris and P. pinaster demonstrated differences in host susceptibility, with P. radiata most susceptible and P. sylvestris least susceptible. Sensitivity to the fungicides fludioxonil and pyraclostrobin varied considerably between isolates from highly effective (half-maximal effective concentration (EC50 < 0.1 ppm to ineffective (EC50 > 100 ppm. This study demonstrates the potential use of simply acquired phenotypical (cultural, morphological and molecular metrics to gain a preliminary estimate of virulence and sensitivity to certain fungicides. It also highlights the necessity of including a range of isolates in fungicide tests and host susceptibility assays, particularly of relevance to tree breeding programmes.

  8. Insecticidal, Repellent and Fungicidal Properties of Novel Trifluoromethylphenyl Amides

    Science.gov (United States)

    2013-01-01

    inhibition even at the higher concentration of 30.0 lM. Captan is an excellent fungicide with a multisite mode of action that is ap- plied to crops such as...trifluoroacetamide (1c) was most active (24 h LD50 19.182 nM, 0.5 lL/insect). However, the 24 h LC50 and LD50 values of fipronil against Ae. aegypti...adults with 24 h LC50 values of 5.6 and 4.9 lg/cm2 for the Oregon- R and 1675 strains, respectively. Fipronil had LC50 values of 0.004 and 0.017 lg/cm2

  9. Enhanced ethanol production, volatile compound biosynthesis and fungicide removal during growth of a newly isolated Saccharomyces cerevisiae strain on enriched pasteurized grape musts

    Energy Technology Data Exchange (ETDEWEB)

    Sarris, Dimitris; Kotseridis, Yorgos; Galiotou-Panayotou, Maria; Papanikolaou, Seraphim [Department of Food Science and Technology, Agricultural University of Athens (Greece); Linga, Maria [Oinognosia, Wine analysis and consulting, Kiato (Greece)

    2009-02-15

    The kinetic behavior of a newly isolated Saccharomyces cerevisiae strain, grown on pasteurized grape musts enriched with industrial sugars, was studied after the addition of various concentrations [0.0 (reference), 0.4 and 2.4 mg/L] of the fungicide quinoxyfen to the medium. Batch-flask cultures were carried out. Significant quantities of biomass (10.0{+-}0.8 g/L) were produced regardless of quinoxyfen addition to the medium; therefore, the addition of the fungicide did not seriously inhibit biomass production. Ethanol was synthesized in very high quantities in all trials (highest concentrations 106.4-119.2 g/L). A slight decrease of ethanol production in terms of both absolute value and conversion yield of ethanol produced per sugar consumed was, however, observed when the quinoxyfen concentration was increased. The addition of quinoxyfen led to significantly lower ethylic ester levels, which also pertains to the acetates analyzed in this study. Fusel alcohol synthesis seemed to be activated when 0.4 mg/L quinoxyfen was added, but at 2.4 mg/L of added fungicide, no statistically significant differences were observed compared with the control trial. Volatile acid levels did not present a uniform trend in relation with the added fungicide. Finally, the fermentation was accompanied by a significant reduction of the fungicide concentration (79-82 wt% fungicide removal). (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  10. Recent Trends in Studies on Botanical Fungicides in Agriculture

    Directory of Open Access Journals (Sweden)

    Mi-Young Yoon

    2013-03-01

    Full Text Available Plants are attacked by various phytopathogenic fungi. For many years, synthetic fungicides have been used to control plant diseases. Although synthetic fungicides are highly effective, their repeated use has led to problems such as environmental pollution, development of resistance, and residual toxicity. This has prompted intensive research on the development of biopesticides, including botanical fungicides. To date, relatively few botanical fungicides have been registered and commercialized. However, many scientists have reported isolation and characterization of a variety of antifungal plant derivatives. Here, we present a survey of a wide range of reported plant-derived antifungal metabolites.

  11. Comparative hygienic assessment of active ingredients content in the air environment after treatment of cereal spiked crops by combined fungicides.

    Science.gov (United States)

    Kondratiuk, Mykola; Blagaia, Anna; Pelo, Ihor

    2018-01-01

    Introduction: The quality of the air environment significantly affects the health of the population. Chemical plant protection products in the spring and summer time may be the main pollutants of the air environment in rural areas. Chemical plant protection products are dangerous substances of anthropogenic origin. If applying pesticides in high concentrations, the risk of poisoning by active ingredients of pesticide preparations in workers directly contacting with it increases. The aim: Comparative hygienic assessment of active ingredients content in the air environment after treatment of cereal spiked crops by combined fungicides was the aim of the work. Materials and methods: Active ingredients of the studied combined fungicides, samples of air, and swabs from workers' skin and stripes from overalls were materials of the research. Methods of full-scale in-field hygienic experiment, gas-liquid chromatography, high-performance liquid chromatography, as well as statistical and bibliographic methods were used in the research. Results and conclusions: Active ingredients of the studied combined fungicides were not detected in the working zone air and atmospheric air at the levels exceeding the limits of its detection by appropriate chromatography methods. Findings confirmed the air environment safety for agricultural workers and rural population if studied combined fungicides are applied following the hygienically approved suggested application rates and in accordance of good agricultural practice rules. However the possible complex risk for workers after certain studied fungicides application may be higher than acceptable due to the elevated values for dermal effects. The complex risk was higher than acceptable in еру case of aerial spraying of both studied fungicides, meanwhile only one combination of active ingredients revealed possible risk for workers applying fungicides by rod method of cereal spiked crops treatment.

  12. The Effect of Fungicides for Seed Treatment on Germination of Barley

    Directory of Open Access Journals (Sweden)

    Vesna Stevanović

    2009-01-01

    Full Text Available The application of chemicals, such as fungicides for seed treatment, is one of the most reliable and perhaps most efficient measures for integrated preservation of crops, and its practicing has become a legal obligation for all seed producers. This investigation was carried out in the laboratory for seed quality and phytopathology of the Small Grains Research Center in Kragujevac. The objective was to establish the effect of fungicides on germination energy and seed germinability (determined after treatments. Two varieties were tested due to a possibility of specific sensitivities of some varieties, so that the results acquired on one variety would not necessarily be valid for another one. Fungicides based on active ingredients from the triasol chemical group had different effects on the energy of germination of barley seeds. Applying Raxil S040-FS, the average germination of barley seeds was 79.3% for the variety Record, and 91.3% for the Grand variety. The variety Record achieved a lower value than the minimum for barley seed germination (88% stipulated by the Rules on Seed Quality of Agricultural Crops.Regardless of barley type, the product Raxil S040-FS showed a statistically significant effect on the number of atypical seedlings and increase in the number of non-germinated seeds, compared to the control.

  13. Contamination of apple orchard soils and fruit trees with copper-based fungicides: sampling aspects.

    Science.gov (United States)

    Wang, Quanying; Liu, Jingshuang; Liu, Qiang

    2015-01-01

    Accumulations of copper in orchard soils and fruit trees due to the application of Cu-based fungicides have become research hotspots. However, information about the sampling strategies, which can affect the accuracy of the following research results, is lacking. This study aimed to determine some sampling considerations when Cu accumulations in the soils and fruit trees of apple orchards are studied. The study was conducted in three apple orchards from different sites. Each orchard included two different histories of Cu-based fungicides usage, varying from 3 to 28 years. Soil samples were collected from different locations varying with the distances from tree trunk to the canopy drip line. Fruits and leaves from the middle heights of tree canopy at two locations (outer canopy and inner canopy) were collected. The variation in total soil Cu concentrations between orchards was much greater than the variation within orchards. Total soil Cu concentrations had a tendency to increase with the increasing history of Cu-based fungicides usage. Moreover, total soil Cu concentrations had the lowest values at the canopy drip line, while the highest values were found at the half distances between the trunk and the canopy drip line. Additionally, Cu concentrations of leaves and fruits from the outer parts of the canopy were significantly higher than from the inner parts. Depending on the findings of this study, not only the between-orchard variation but also the within-orchard variation should be taken into consideration when conducting future soil and tree samplings in apple orchards.

  14. Bioremediation of fungicides by spent mushroom substrate and its associated microflora.

    Science.gov (United States)

    Ahlawat, O P; Gupta, Pardeep; Kumar, Satish; Sharma, D K; Ahlawat, K

    2010-10-01

    Experiments were conducted both under in vitro and in situ conditions to determine the biodegradation potential of button mushroom spent substrate (SMS) and its dominating microbes (fungi and bacteria) for carbendazim and mancozeb, the commonly used agricultural fungicides. During 6 days of incubation at 30 ± 2°C under broth culture conditions, highest degradation of carbendazim (17.45%) was recorded with B-1 bacterial isolate, while highest degradation of mancozeb (18.05%) was recorded with Trichoderma sp. In fungicide pre-mixed sterilized SMS, highest degradation of carbendazim (100.00-66.50 μg g(-1)) was recorded with mixed inoculum of Trichoderma sp. and Aspergillus sp., whereas highest degradation of mancozeb (100.00-50.50 μg g(-1)) was with mixed inoculum of Trichoderma sp., Aspergillus sp. and B-I bacterial isolate in 15 days of incubation at 30 ± 2°C. All these microbes both individually as well as in different combinations grew well and produced extracellular lignolytic enzymes on SMS, which helped in fungicides degradation. Under in situ conditions, among three different proportions of SMS (10, 20 and 30%, w/w) mixed with fungicide pre-mixed soil (100 μg g(-1) of soil), the degradation of carbendazim was highest in 30% SMS treatment, while for mancozeb it was in 20% SMS treatment. The residue levels of both fungicides decreased to half of their initial concentration after 1 month of SMS mixing.

  15. Thrombin-induced rabbit platelet microbicidal protein is fungicidal in vitro.

    Science.gov (United States)

    Yeaman, M R; Ibrahim, A S; Edwards, J E; Bayer, A S; Ghannoum, M A

    1993-03-01

    Platelet microbicidal protein (PMP) is released from platelets in response to thrombin stimulation. PMP is known to possess in vitro bactericidal activity against Staphylococcus aureus and viridans group streptococci. To determine whether PMP is active against other intravascular pathogens, we evaluated its potential fungicidal activity against strains of Candida species and Cryptococcus neoformans. Anionic resin adsorption and gel electrophoresis confirmed that the fungicidal activity of PMP resided in a small (approximately 8.5-kDa), cationic protein, identical to previous studies of PMP-induced bacterial killing (M.R. Yeaman, S.M. Puentes, D.C. Norman, and A.S. Bayer, Infect. Immun. 60:1202-1209, 1992). When assayed over a 180-min period in vitro, the susceptibilities of these fungi to PMP varied considerably. Generally, Candida albicans strains (mean survival, 33.5% +/- 6.9% [n = 6]) as well as isolates of Candida glabrata (mean survival, 50.8% +/- 2.9% [n = 2]) were the most susceptible to killing by PMP, while Candida guillermondii and Candida parapsilosis were relatively resistant to PMP-induced killing. Compared with C. albicans, C. neoformans was relatively resistant to the fungicidal activity of PMP, with a mean survival among the isolates studied of 77.4% +/- 12.4% (n = 6). Against C. albicans, PMP-induced fungicidal activity was time dependent (range, 0 to 180 min), PMP concentration dependent (range, 10 to 150 U/ml), and inversely related to the fungal inoculum (range, 5 x 10(3) to 1 x 10(5) CFU/ml). Scanning electron microscopy of PMP-exposed C. albicans and C. neoformans cells revealed extensive surface damage and collapse, suggesting that the site of PMP fungicidal action may directly or indirectly involve the fungal cell envelope.

  16. Effects of the fungicide metiram in outdoor freshwater microcosms: responses of invertebrates, primany producers and microbes

    OpenAIRE

    Ronghua, Lin; Buijse-Bogdan, L.L.; Rocha Dimitrov, M.; Dohmen, P.; Kosol, Sujitra; Maltby, L.; Roessink, I.; Sinkeldam, J.A.; Smidt, H.; Wijngaarden, van, R.P.A.; Brock, T.C.M.

    2012-01-01

    The ecological impact of the dithiocarbamate fungicide metiram was studied in outdoor freshwater microcosms, consisting of 14 enclosures placed in an experimental ditch. The microcosms were treated three times (interval 7 days) with the formulated product BAS 222 28F (Polyram®). Intended metiram concentrations in the overlying water were 0, 4, 12, 36, 108 and 324 μg a.i./L. Responses of zooplankton, macroinvertebrates, phytoplankton, macrophytes, microbes and community metabolism endpoints we...

  17. Development of biodegradable fungicide by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Keun; Kim, Dong Sub [KAERI, Daejeon (Korea, Republic of)

    2011-01-15

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by pot experiment and It was promising to prevent pepper, Chinese cabbage and radish from anthrax, phytophthora and root rot

  18. Development of biodegradable fungicide by radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Youngkeun; Kim, Dongsub

    2012-03-15

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by field test and it was promising to prevent Chinese cabbage and radish from phytophthora and root rot.

  19. Development of biodegradable fungicide by radiation

    International Nuclear Information System (INIS)

    Lee, Young Keun; Kim, Dong Sub

    2011-01-01

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by pot experiment and It was promising to prevent pepper, Chinese cabbage and radish from anthrax, phytophthora and root rot

  20. Development of biodegradable fungicide by radiation

    International Nuclear Information System (INIS)

    Lee, Young Jeun; Kim, Dong Sub

    2010-01-01

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Sixteen antifungal microbes were isolated and 4 antifungal activity enhanced mutants were induced by using radiation. P. lentimorbus WJ5a17 had 41% higher antifungal activity than the wild type. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified

  1. Development of biodegradable fungicide by radiation

    International Nuclear Information System (INIS)

    Lee, Youngkeun; Kim, Dongsub

    2012-03-01

    To develop the fungicide which is biodegradable and alternative to chemical pesticide that has an side effect of environmental pollution, Mutant induction of the enhanced antifungal activity was studied by using radiation. Characteristics and structure of antifungal biomaterials derived from these mutants were analysed. Two biomaterials related to the antifungal activity from the above mutant were isolated and purified. Microbial pesticide were manufactured in combination of various additives. Antiphytopathogenic effects were proven by field test and it was promising to prevent Chinese cabbage and radish from phytophthora and root rot

  2. Study of fungicidal properties of colloidal silver nanoparticles (AgNPs on trout egg pathogen, Saprolegnia sp.

    Directory of Open Access Journals (Sweden)

    Seyed Ali Johari

    2015-05-01

    Full Text Available Silver nanoparticles (AgNPs are known to have bactericidal and fungicidal effects. Since, there is few information available on the interaction of colloidal nanosilver with fish pathogens. Hence, the current study investigated the effects of colloidal AgNPs on the in vitro growth of the fish pathogen Saprolegnia sp.. Before the experiments, various important properties of AgNPs were well-characterized. The antifungal activity of AgNPs was then evaluated by determining the minimum inhibitory concentrations (MICs using two-fold serial dilutions of colloidal nanosilver in a glucose yeast extract agar at 22ºC. The growth of Saprolegnia sp. on the AgNPs agar treatments was compared to that of nanosilver-free agar as controls. The results showed that AgNPs have an inhibitory effect on the in vitro growth of the tested fungi. The MIC of AgNPs for Saprolegnia sp. was calculated at 1800 mg/L, which is equal to 0.18 percent. It seems that AgNPs could be a proper replacement for teratogenic and toxic agents, such as malachite green. In addition, the indirect use of AgNPs could be a useful method for providing new antifungal activity in aquaculture systems.

  3. Efficiency of Elite Fungicide for Control of Pistachio Gummosis

    Directory of Open Access Journals (Sweden)

    Mohammad Moradi

    2017-05-01

    Full Text Available Several species of Phytophthora cause crown and root rot diseases of herbaceous and woody plants. Crown and root rot of pistachio trees cause significant damages in infected orchards. The effect of foliar application with Elite (fosetyl-Al in 2 and 2.5 g/l was evaluated in greenhouse experiments. The frequency of mortality, fresh and dry weight of roots and shoots, height, intensity of crown root colonization using CAMA-PARP medium was determined. Under greenhouse experiments, foliar application with Elite increased height, fresh and dry weight of shoots and root either in inoculation with and without Phytophthora drechsleri. The effects of Elite were more pronounced in roots, which increased the fresh and dry weight of root 1.3 and 2.5 times compared to those not sprayed with Elite, respectively. On the other hand, the application of Elite before or on the day of inoculation significantly reduced the frequency of mortality, which ranged from 35 to 90% (P ≤ 0.01. Crown and root colonization of pistachio seedling was affected by both the concentration of Elite and reduced the frequency of crown and root colonization of seedling. When fungicide and pathogen were applied at the same time, the frequency of colonization reduced to 18% and 36% for 2 and 2.5 g/l, respectively, and 43% and 60% when seedlings were treated with fungicide before P. drechsleri inoculations. The highest effect was seen in foliar application of Elite seven days before inoculation in 2.5 g/l. Further investigations have been conducted to understand the effect of Elite in infected trees as well as modeling of Elite application via soil drench, foliar application or trunk injection.

  4. The fungicide mancozeb induces toxic effects on mammalian granulosa cells

    International Nuclear Information System (INIS)

    Paro, Rita; Tiboni, Gian Mario; Buccione, Roberto; Rossi, Gianna; Cellini, Valerio; Canipari, Rita; Cecconi, Sandra

    2012-01-01

    The ethylene-bis-dithiocarbamate mancozeb is a widely used fungicide with low reported toxicity in mammals. In mice, mancozeb induces embryo apoptosis, affects oocyte meiotic spindle morphology and impairs fertilization rate even when used at very low concentrations. We evaluated the toxic effects of mancozeb on the mouse and human ovarian somatic granulosa cells. We examined parameters such as cell morphology, induction of apoptosis, and p53 expression levels. Mouse granulosa cells exposed to mancozeb underwent a time- and dose-dependent modification of their morphology, and acquired the ability to migrate but not to proliferate. The expression level of p53, in terms of mRNA and protein content, decreased significantly in comparison with unexposed cells, but no change in apoptosis was recorded. Toxic effects could be attributed, at least in part, to the presence of ethylenthiourea (ETU), the main mancozeb catabolite, which was found in culture medium. Human granulosa cells also showed dose-dependent morphological changes and reduced p53 expression levels after exposure to mancozeb. Altogether, these results indicate that mancozeb affects the somatic cells of the mammalian ovarian follicles by inducing a premalignant-like status, and that such damage occurs to the same extent in both mouse and human GC. These results further substantiate the concept that mancozeb should be regarded as a reproductive toxicant. Highlights: ► The fungicide mancozeb affects oocyte spindle morphology and fertilization rate. ► We investigated the toxic effects of mancozeb on mouse and human granulosa cells. ► Granulosa cells modify their morphology and expression level of p53. ► Mancozeb induces a premalignant-like status in exposed cells.

  5. The fungicide mancozeb induces toxic effects on mammalian granulosa cells

    Energy Technology Data Exchange (ETDEWEB)

    Paro, Rita [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy); Tiboni, Gian Mario [Department of Medicine and Aging, Section of Reproductive Sciences, University “G. D' Annunzio”, Chieti-Pescara (Italy); Buccione, Roberto [Tumor Cell Invasion Laboratory, Consorzio Mario Negri Sud, Santa Maria Imbaro, Chieti (Italy); Rossi, Gianna; Cellini, Valerio [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy); Canipari, Rita [Department of Anatomy, Histology, Forensic Medicine and Orthopedics, Section of Histology and Embryology, School of Pharmacy and Medicine, “Sapienza” University of Rome, Rome (Italy); Cecconi, Sandra, E-mail: sandra.cecconi@cc.univaq.it [Department of Health Sciences, University of L' Aquila, Via Vetoio, L' Aquila (Italy)

    2012-04-15

    The ethylene-bis-dithiocarbamate mancozeb is a widely used fungicide with low reported toxicity in mammals. In mice, mancozeb induces embryo apoptosis, affects oocyte meiotic spindle morphology and impairs fertilization rate even when used at very low concentrations. We evaluated the toxic effects of mancozeb on the mouse and human ovarian somatic granulosa cells. We examined parameters such as cell morphology, induction of apoptosis, and p53 expression levels. Mouse granulosa cells exposed to mancozeb underwent a time- and dose-dependent modification of their morphology, and acquired the ability to migrate but not to proliferate. The expression level of p53, in terms of mRNA and protein content, decreased significantly in comparison with unexposed cells, but no change in apoptosis was recorded. Toxic effects could be attributed, at least in part, to the presence of ethylenthiourea (ETU), the main mancozeb catabolite, which was found in culture medium. Human granulosa cells also showed dose-dependent morphological changes and reduced p53 expression levels after exposure to mancozeb. Altogether, these results indicate that mancozeb affects the somatic cells of the mammalian ovarian follicles by inducing a premalignant-like status, and that such damage occurs to the same extent in both mouse and human GC. These results further substantiate the concept that mancozeb should be regarded as a reproductive toxicant. Highlights: ► The fungicide mancozeb affects oocyte spindle morphology and fertilization rate. ► We investigated the toxic effects of mancozeb on mouse and human granulosa cells. ► Granulosa cells modify their morphology and expression level of p53. ► Mancozeb induces a premalignant-like status in exposed cells.

  6. In vitro screening of fungicides and antagonists against Sclerotium ...

    African Journals Online (AJOL)

    A study was conducted in the microbiology laboratory of Plant Pathology Department, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, during 2010 to 2011 to control Sclerotium rolfsii with fungicides and Trichoderma harzianum. Six fungicides namely Provax-200, Bavistin, Ridomil, Dithane M-45, ...

  7. Coating with fungicide and different doses of fertilizer in vinhatico ...

    African Journals Online (AJOL)

    Thus, the aim of this study was to evaluate and identify the physical and physiological quality of mahogany seeds that are coated with fertilizer and fungicide. The treatments were: seed coating with sand + lime + fungicide with different doses of fertilizers. The seeds were evaluated in the laboratory and in a greenhouse.

  8. Pathogenicity and fungicide sensitivity of the causal agent of ...

    African Journals Online (AJOL)

    The pathogenicity of the fungus and its cross-infection potential were determined on mango, avocado, papaya and banana fruits. The sensitivity of the pathogen to fungicides was determined by assessing radial mycelial growth on potato dextrose agar (PDA) amended with nine different fungicides (Bendazim, Funguran, ...

  9. Interactions between yeasts, fungicides and apple fruit russeting

    NARCIS (Netherlands)

    Gildemacher, P.R.; Heijne, B.; Silvestri, M.; Houbraken, J.; Hoekstra, E.; Theelen, B.; Boekhout, T.

    2006-01-01

    The effect of inoculations with yeasts occurring on apple surfaces and fungicide treatments on the russeting of Elstar apples was studied. Captan, dithianon and a water treatment were implemented to study the interaction between the fungicides, the inoculated yeast species and Aureobasidium

  10. Factors influencing activity of triazole fungicides towards Botrytis cinerea.

    NARCIS (Netherlands)

    Stehmann, C.; Waard, de M.A.

    1996-01-01

    The activity of triazole fungicides towards Botrytis cinerea was investigated in vitro (radial growth on fungicide-amended agar) and in vivo (foliar-sprayed tomato plants and dip-treated grapes). In both tests the benzimidazoles, benomyl and thiabendazole, and the dicarboximides, iprodione and

  11. In-vitro evaluation of fungicides, plant extracts and bio-control agents against rice blast pathogen magnaporthe oryzae couch

    International Nuclear Information System (INIS)

    Hajano, J.U.D.; Lodhi, M.; Pathan, M.A.; Khanzada, A.; Shah, G.S.

    2012-01-01

    Among 5 fungicides viz., Thiophanate-methyl, Carbendazim, Fosetyl-aluminium, Mancozeb and Copper oxychloride, used against the Magnaporthe oryzae, only Mancozeb appeared as the highly effective fungicide that completely inhibited the mycelial growth of the fungus. All other fungicides showed little effect at higher concentrations. The extracts of garlic (Allium sativum L.), neem (Azadirachta indica L.) and calatropis (Calotropis procera L.) when used against M. oryzae by food poisoning method, only higher dose of garlic completely inhibited the mycelial growth of the test fungus. Six bio-control agents viz., Trichoderma harzianum, Trichoderma polysporum, Trichoderma pseudokoningii, Gliocladium virens, Paecilomyces variotii and Paecilomyces lilacinus were used. Maximum mycelial inhibition of M. oryzae was provided by P. lilacinus followed by Trichoderma spp. (author)

  12. Protective, curative and eradicative activities of fungicides against grapevine rust

    Directory of Open Access Journals (Sweden)

    Francislene Angelotti

    2014-01-01

    Full Text Available The protective, eradicative and curative activities of the fungicides azoxystrobin, tebuconazole, pyraclostrobin+metiram, and ciproconazole against grapevine rust, were determined in greenhouse. To evaluate the protective activity, leaves of potted ´Niagara´ (Vitis labrusca vines were artificially inoculated with an urediniospore suspension of Phakopsora euvitis four, eight or forteen days after fungicidal spray; and to evaluate the curative and eradicative activities, leaves were sprayed with fungicides two, four or eight days after inoculation. Disease severity was assessed 14 days after each inoculation. All tested fungicides present excellent preventive activity against grapevine rust; however, tebuconazole and ciproconazole provide better curative activity than azoxystrobin and pyraclostrobin+metiram. It was observed also that all tested fungicides significantly reduced the germination of urediniospore produced on sprayed leaves.

  13. Insecticidal, repellent and fungicidal properties of novel trifluoromethylphenyl amides.

    Science.gov (United States)

    Tsikolia, Maia; Bernier, Ulrich R; Coy, Monique R; Chalaire, Katelyn C; Becnel, James J; Agramonte, Natasha M; Tabanca, Nurhayat; Wedge, David E; Clark, Gary G; Linthicum, Kenneth J; Swale, Daniel R; Bloomquist, Jeffrey R

    2013-09-01

    Twenty trifluoromethylphenyl amides were synthesized and evaluated as fungicides and as mosquito toxicants and repellents. Against Aedes aegypti larvae, N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-3,5-dinitrobenzamide (1e) was the most toxic compound (24 h LC50 1940 nM), while against adults N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-2,2,2-trifluoroacetamide (1c) was most active (24 h LD50 19.182 nM, 0.5 μL/insect). However, the 24 h LC50 and LD50 values of fipronil against Ae. aegypti larvae and adults were significantly lower: 13.55 nM and 0.787 × 10(-4) nM, respectively. Compound 1c was also active against Drosophila melanogaster adults with 24 h LC50 values of 5.6 and 4.9 μg/cm(2) for the Oregon-R and 1675 strains, respectively. Fipronil had LC50 values of 0.004 and 0.017 μg/cm(2) against the two strains of D. melanogaster, respectively. In repellency bioassays against female Ae. aegypti, 2,2,2-trifluoro-N-(2-(trifluoromethyl)phenyl)acetamide (4c) had the highest repellent potency with a minimum effective dosage (MED) of 0.039 μmol/cm(2) compared to DEET (MED of 0.091 μmol/cm(2)). Compound N-(2-(trifluoromethyl)phenyl)hexanamide (4a) had an MED of 0.091 μmol/cm(2) which was comparable to DEET. Compound 4c was the most potent fungicide against Phomopsis obscurans. Several trends were discerned between the structural configuration of these molecules and the effect of structural changes on toxicity and repellency. Para- or meta- trifluoromethylphenyl amides with an aromatic ring attached to the carbonyl carbon showed higher toxicity against Ae. aegypti larvae, than ortho- trifluoromethylphenyl amides. Ortho- trifluoromethylphenyl amides with trifluoromethyl or alkyl group attached to the carbonyl carbon produced higher repellent activity against female Ae. aegypti and Anopheles albimanus than meta- or para- trifluoromethylphenyl amides. The presence of 2,6-dichloro- substitution on the phenyl ring of the amide had an influence on larvicidal and repellent

  14. Pasteurellaceae bacteria from the oral cavity of Tasmanian devils (Sarcophilus Harrisii) show high minimum inhibitory concentration values towards aminoglycosides and clindamycin

    DEFF Research Database (Denmark)

    Gutman, N.; Hansen, Mie Johanne; Bertelsen, M. F.

    2016-01-01

    of the oral microbiota. In medical management of such bite wounds, antimicrobial susceptibility profiles are crucial. Prior to this investigation, no available data on minimal inhibitory concentration (MIC) values existed. A total of 26 isolates obtained from the oral cavity of 26 healthy Tasmanian devils...... for antimicrobial therapy against bite wound infections caused by Pasteurellaceae originating from the oral cavity of Tasmanian devils....

  15. Minimum Effective Concentration of Bupivacaine in Ultrasound-Guided Femoral Nerve Block after Arthroscopic Knee Meniscectomy: A Randomized, Double-Blind, Controlled Trial.

    Science.gov (United States)

    Moura, Ed Carlos Rey; de Oliveira Honda, Claudio A; Bringel, Roberto Cesar Teixeira; Leal, Plinio da Cunha; Filho, Gasper de Jesus Lopes; Sakata, Rioko Kinmiko

    2016-01-01

    Adequate analgesia is important for early hospital discharge after meniscectomy. A femoral nerve block may reduce the need for systemic analgesics, with fewer side effects; however, motor block can occur. Ultrasound-guided femoral nerve block may reduce the required local anesthetic concentration, preventing motor block. The primary objective of this study was to determine the lowest effective analgesic concentration of bupivacaine in 50% (EC50) and in 90% (EC90) of patients for a successful ultrasound-guided femoral nerve block in arthroscopic knee meniscectomy. This was a prospective, randomized, double-blind, controlled trial. This study was conducted at Hospital São Domingos. A total of 52 patients undergoing arthroscopic knee meniscectomy were submitted to ultrasound-guided femoral nerve block using 22 mL bupivacaine. The bupivacaine concentration given to a study patient was determined by the response of the previous patient (a biased-coin design up-down sequential method). If the previous patient had a negative response, the bupivacaine concentration was increased by 0.05% for the next case. If the previous patient had a positive response, the next patient was randomized to receive the same bupivacaine concentration (with a probability of 0.89) or to have a decrease by 0.05% (with a probability of 0.11). A successful block was defined by a numerical pain intensity scale score different evaluations. If the pain intensity score was = 4 (moderate or severe pain) at any time, the block was considered failed. General anesthesia was induced with 30 µg/kg alfentanil and 2 mg/kg propofol, followed by propofol maintanance, plus remifentanil if needed. Postoperative analgesia supplementation was performed with dipyrone; ketoprofen and tramadol were given if needed. The following parameters were evaluated: numerical pain intensity score, duration of analgesia, supplementary analgesic dose in 24 hours, and need for intraoperative remifentanil. The EC50 was 0.160 (95

  16. Evaluation of fungicidal and fungistatic activity of plant essential oils towards plant pathogenic and saprophytic fungi

    Directory of Open Access Journals (Sweden)

    Zia BANIHASHEMI

    2011-09-01

    Full Text Available   The contact and vapor effects of essential oils from different plants were studied in vitro for fungicidal and fungistatic activity towards different Basidiomycete, Ascomycete, Zygomycete and Oomycete taxa. Of nine essential oils tested, most were fungicidal at very low concentrations to most of the fungi. Hyphae were more sensitive than spores to the formulations. The essential oils citral, β-citronellol, geraniol and oil of lavender, at 1 μL mL-1 medium or 12 μL L-1 of air, inhibited growth and germination in the fungal species examined. Different species of fungal genera reacted differently to the formulations. Some of the formulations were fungistatic to spore germination.

  17. Metallothionein induction, antioxidative responses, glycogen and growth changes in Tubifex tubifex (Oligochaete) exposed to the fungicide, fenhexamid

    International Nuclear Information System (INIS)

    Mosleh, Yahia Y.; Paris-Palacios, Severine; Couderchet, Michel; Biagianti-Risbourg, Sylvie; Vernet, Guy

    2005-01-01

    Laboratory studies were conducted to determine the effects of different concentrations of fenhexamid (0.1, 1, and 10 mg L -1 ) on growth, oxidative stress, protein, glycogen, and metallothionein (MT) contents in Tubifex tubifex after an exposure of 2, 4, and 7 days. In addition, residues of the fungicide were followed in water and in the worms. In water, fenhexamid concentration decreased slowly (maximum - 2±0.03% after 2 days for 1 mg L -1 ). In the worms, it increased after 4 days and decreased thereafter, confirming that the worms were exposed to the fungicide and not to a degradation product. LC 50 values were between 95.22±5.36 and 32.11±1.8 mg L -1 depending on exposure time. Exposure to fenhexamid had a negative effect on T. tubifex growth (maximum effect -12.2±0.8% after 7 days with 10 mg L -1 ) demonstrating the toxic effect of the pesticide. This growth rate decrease was accompanied by a reduction in protein and glycogen contents. The activity of catalase (CAT), and glutathione reductase (GR) increased in response to the fungicide demonstrating an oxidative stress in the worms. In contrast glutathion-S-transferase activity (GST) decreased. Exposure to fenhexamid also induced synthesis of MT (maximum +78±8% after 2 days for 10 mg L -1 ). The specificity of MT concentration increase in response to metals is discussed. - Exposure to the fungicide fenhexamid increased metallothionein levels in Tubifex tubifex

  18. Minimum concentrations of NO/sub 2/ causing acute effects on the respiratory gas exchange and airway-resistance in patients with chronic bronchitis

    Energy Technology Data Exchange (ETDEWEB)

    von Nieding, G; Wagner, M; Krekeler, H; Smidt, U; Muysers, K

    1971-01-01

    Nitrogen dioxide-air mixtures containing 0.5 to 5.0 ppM NO/sub 2/ were inhaled by 88 patients with chronic bronchitis over a 15-minute period for a total of 30 breaths during studies investigating the effects of the gas on airway resistance and respiratory gas exchange. End-expiratory oxygen pressures remained nearly constant during inhalation of 4 or 5 ppM NO/sub 2/, though significant decreases in arterial oxygen pressure accompanied by increases in end-expiratory-arterial oxygen pressure difference occurred. Inhalation of 2 ppM NO/sub 2/ did not decrease arterial oxygen pressure. Airway resistances increased significantly down to 1.5 ppM NO/sub 2/ concentrations. Lower concentrations caused no significant effects.

  19. The presence of bromuconazole fungicide pollutant in organic waste anaerobic fermentation

    Science.gov (United States)

    Hariyadi, H. R.

    2017-03-01

    The presence of bromuconazole fungicide pollutant in organic waste anaerobic fermentation was carried out as well as the influence phenol and benzoate, and biodegradation of bromuconazole. Bromuconazole is a fungicide effective against Ascomycetes, Basidiomycetes and fungi imperfecti in cereals, grapes, top fruits and vegetables. It is also effective against Alternaria and Fusarium sp. The remaining fungicide in leaves might contaminates landfill. One month of organic waste added with bromuconazole was anaerobically incubated in 500 mL bottles at 30°C without shaking in dark room. High-Performance Liquid Chromatography (HPLC) with UV detector and a 100 RP 185μm Lichrosphere column was used to determine bromuconazole concentration. Methane content was determined by Gas Chromatography (GC) method equipped with a flame ionization detector and a metal column packed with 5% neopentyl glycol sebacate and 1% H3PO4 on Chromosorb W-AW (mesh 80-100). After incubation for 225 days, bromuconazole of 200 mg/L inhibited the production of methane (99.5 mM) significantly, but did not inhibit the production of volatile fatty acids. The addition of 100 mg/L phenol or 146 mg/L benzoate increased the production of methane, 143 mM and 135.2 mM, respectively compared with control (121.8 mM). In anaerobic conditions, the presence of toxic pollutants such as fungicide bromuconazole in landfills sites may cause further problems with the accumulation of volatile fatty acids in leachate. Further study to determine the threshold, the presence of bromconazole in low concentration (less than 200 mg/L) on the methane production is recommended.

  20. Effects of bottom water oxygen concentrations on mercury distribution and speciation in sediments below the oxygen minimum zone of the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, P.; Mason, R.P.; Jayachandran, S.; Vudamala, K.; Armoury, K.; Sarkar, Arindam; Chakraborty, S.; Bardhan, P.; Naik, R.

    benthic flux of MeHg to the overlying water (Hollweg et al., 2010; Balcom et al., 2008). On the contrary, however, a study in the Gulf of Mexico did not find that MeHg in bottom waters correlated with the extent of hypoxia (Liu et al., 2015... in the sediments of the so-called “dead zone” in the Gulf of Mexico. Others (Mason et al., 2006; Emili et al., 2011) have shown that total Hg and MeHg fluxes from sediments are enhanced by low oxygen concentrations in the overlying waters. The aim of this study...

  1. Action of mercury as a soil fungicide

    Energy Technology Data Exchange (ETDEWEB)

    Booer, J R

    1951-01-01

    Metallic mercury and mercury compounds in the soil retard the growth of plants. The development of mosses and lichens is inhibited, and experimental evidence shows that the growth of toadstools on turf and the activity of ascomycetes is retarded by mercury. In vitro, mercury has no fungicidal action but the rate of growth of hyphae is reduced by mercury vapour. The lack of fungicial properties of mercury and its good performance in controlling certain soil-borne diseases are reconciled by assuming that a differential retardation disturbs the relationships necessary for infection. This assumption is supported by diagrams which treat the rates of growth of the parasite and the host as population characteristics normally distributed. 21 references, 10 figures, 5 tables.

  2. Toxicity evaluation of new agricultural fungicides in primary cultured cortical neurons.

    Science.gov (United States)

    Regueiro, Jorge; Olguín, Nair; Simal-Gándara, Jesús; Suñol, Cristina

    2015-07-01

    Fungicides are crucial for food protection as well as for the production of crops of suitable quality and quantity to provide a viable economic return. Like other pesticides, fungicides are widely sprayed on agricultural land, especially in wine-growing areas, from where they can move-off after application. Furthermore, residues of these agrochemicals can remain on crops after harvest and even after some food processing operations, being a major exposure pathway. Although a relatively low toxicity has been claimed for this kind of compounds, information about their neurotoxicity is still scarce. In the present study, nine fungicides recently approved for agricultural uses in the EU - ametoctradin, boscalid, cyazofamid, dimethomorph, fenhexamid, kresoxim-methyl, mepanipyrim, metrafenone and pyraclostrobin - have been evaluated for their toxicity in primary cultured mouse cortical neurons. Exposure to 0.1-100µM for 7 days in vitro resulted in a dose-dependent toxicity in the MTT cell viability assay. Strobilurin fungicides kresoxim-methyl (KR) and pyraclostrobin (PY) were the most neurotoxic compounds (lethal concentration 50 were in the low micromolar and nanomolar levels, respectively) causing a rapid raise in intracellular calcium [Ca(2+)]i and strong depolarization of mitochondrial membrane potential. KR- and PY-induced cell death was reversed by the calcium channels blockers MK-801 and verapamil, suggesting that calcium entry through NMDA receptors and voltage-operated calcium channels are involved in KR- and PY-induced neurotoxicity. These results highlight the need for further evaluation of their neurotoxic effects in vivo. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Coating with fungicide and different doses of fertilizer in vinhatico ...

    African Journals Online (AJOL)

    Lucas

    2016-09-21

    Sep 21, 2016 ... The treatments were: seed coating with sand + lime + fungicide with different doses of .... The index was calculated based on the formula of Maguire (1962). ..... Ludwig EJ, Nunes UR, Mertz LM, Silva JR, Nunes SCP (2014).

  4. Effects of Conazole Fungicides on Spontaneous Activity in Neural Networks

    Science.gov (United States)

    Hexaconazole (HEX), Tetraconazole (TET), Fluconazole (FLU), and Triadimefon (TRI) are conazole fungicides, used to control powdery mildews on crops, and as veterinary and clinical treatments. TRI, a demethylation inhibitor, is neurotoxic in vivo, and previous in vitro experiments...

  5. Federal Insecticide, Fungicide, and Rodenticide Act Section 18 Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — Section 18 of Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) authorizes EPA to allow an unregistered use of a pesticide for a limited time if EPA...

  6. Biological activity of triazole fungicides towards Botrytis cinerea

    OpenAIRE

    Stehmann, C.

    1995-01-01

    Botrytis cinerea Pers. ex Fr., the causal agent of grey mould, is one of the most ubiquitous plant pathogens. The fungus is of high economic importance in various major crops and during transport and storage of agricultural products. Protectant fungicides such as chlorothalonil, dichlofluanid, folpet or thiram are widely used for disease control. Since their introduction in the 1960S/1970s, systemic fungicides such as the benzimidazoles or dicarboximides have bee...

  7. Widespread contamination of wildflower and bee-collected pollen with complex mixtures of neonicotinoids and fungicides commonly applied to crops

    OpenAIRE

    David, Arthur; Botias, Cristina; Abdul-Sada, Alaa; Nicholls, Elizabeth; Rotheray, Ellen L; Hill, Elizabeth M; Goulson, Dave

    2016-01-01

    There is considerable and ongoing debate as to the harm inflicted on bees by exposure to agricultural pesticides. In part, the lack of consensus reflects a shortage of information on field-realistic levels of exposure. Here, we quantify concentrations of neonicotinoid insecticides and fungicides in the pollen of oilseed rape, and in pollen of wildflowers growing near arable fields. We then compare this to concentrations of these pesticides found in pollen collected by honey bees and in pollen...

  8. Immunomodulatory effects of the fungicide Mancozeb in agricultural workers

    International Nuclear Information System (INIS)

    Corsini, Emanuela; Birindelli, Sarah; Fustinoni, Silvia; De Paschale, Gioia; Mammone, Teresa; Visentin, Sara; Galli, Corrado L.; Marinovich, Marina; Colosio, Claudio

    2005-01-01

    Available data suggest that ethylenebisdithiocarbamates (EBDCs) may have immunomodulatory effects. This study aimed to investigate the immunological profile of farmers exposed to Mancozeb, an EBDC fungicide, through the determination of several serum, cellular, and functional immune parameters. Twenty-six healthy subjects entered the study, 13 vineyards exposed to Mancozeb and 13 unexposed controls. Exposure was assessed through the determination of ethylentiourea (ETU) in urine. Complete and differential blood count, serum immunoglobulins, complement fractions, autoantibodies, lymphocyte subpopulations, proliferative response to mitogens, natural killer (NK) activity, and cytokine production were measured. Post-exposure samples showed ETU urine concentration significantly higher than pre-exposure and control groups. A significant increase in CD19+ cells, both percentage and absolute number, and a significant decrease in the percentage of CD25+ cells were found in post-exposure samples compared to controls. A statistically significant increase in the proliferative response to phorbol myristate acetate plus ionomycin (PMA + ionomycin) was observed in the post-exposure group compared to controls and baseline, while a significant reduction in LPS-induced TNF-α release in post-exposure samples was observed. Overall, our results suggest that low-level exposure to Mancozeb has slight immunomodulatory effects, and point out a method adequate to reveal immune-modifications in workers occupationally exposed to potential immunotoxic compounds, based on a whole blood assay

  9. Effects of Insecticides and Fungicides Commonly Used in Tomato Production on Phytoseiulus persimilis (Acari: Phtyoseiidae).

    Science.gov (United States)

    Ditillo, J L; Kennedy, G G; Walgenbach, J F

    2016-12-01

    The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is an important pest of tomatoes in North Carolina. Resident populations of the predatory mite Phytoseiulus persimilis have recently been detected on field-grown tomatoes in central North Carolina, and potentially can be a useful biological control agent against T. urticae Laboratory bioassays were used to assess lethal and reproductive effects of 10 insecticides and five fungicides commonly used in commercial tomato production (chlorantraniliprole, spinetoram, permethrin, imidacloprid, dimethoate, dinotefuran, thiamethoxam, bifenthrin, fenpropathrin, lambda-cyhalothrin, azoxystrobin, chlorothalonil, boscalid, cyazofamid, and mancozeb) on P. persimilis adult females and eggs. Insecticides were tested using concentrations equivalent to 1×, 0.5×, and 0.1× of the recommended field rates. Fungicides were tested at the 1× rate only. Dimethoate strongly impacted P. persimilis with high adult mortality, reduced fecundity, and reduced hatch of eggs laid by treated adults, particularly at high concentrations. The pyrethroids lambda-cyhalothrin, bifenthrin, and fenpropathrin were associated with repellency and reproductive effects at high concentrations. Bifenthrin additionally caused increased mortality at high concentrations. Chlorantraniliprole, dinotefuran, and permethrin did not significantly affect mortality or reproduction. Imidacloprid significantly reduced fecundity and egg viability, but was not lethal to adult P. persimilis Thiamethoxam negatively impacted fecundity at the 1× rate. There were no negative effects associated with fungicide exposure with the exception of mancozeb, which impacted fecundity. Field trials were conducted to explore the in vivo impacts of screened insecticides on P. persimilis populations in the field. Field trials supported the incompatibility of dimethoate with P. persimilis populations. © The Authors 2016. Published by Oxford University Press on behalf

  10. A turn-on supramolecular fluorescent probe for sensing benzimidazole fungicides and its application in living cell imaging

    Science.gov (United States)

    Tang, Qing; Zhang, Jing; Sun, Tao; Wang, Cheng-Hui; Huang, Ying; Zhou, Qingdi; Wei, Gang

    2018-02-01

    A cucurbit[8]uril-based turn-on supramolecular fluorescent probe between cucurbit[8]uril (Q[8]) and pyronine Y (PyY) (designated 2PyY@Q[8]) in acidic aqueous solution showed a remarkable fluorescence 'turn-on' response to benzimidazole fungicides such as thiabendazole, fuberidazole and carbendazim. The 2PyY@Q[8] fluorescent probe can be used to detect benzimidazole fungicides with high sensitivity and selectivity with a detection limit of 10- 8 mol/L. A good linear relationship of emission intensity at 580 nm for benzimidazole fungicides at concentrations of 0.4-5.0 μmol/L was observed. The proposed sensing mechanism was investigated using 1H NMR spectroscopy combined with density functional theory calculations at the B3LYP/6-31G(d) level. The cell imaging study showed that the 2PyY@Q[8] complex could be used to image benzimidazole fungicide in prostate cancer (PC3) cells, which may help to elucidate relevant biological processes at the molecular level.

  11. Protocol for the "Michigan Awareness Control Study": A prospective, randomized, controlled trial comparing electronic alerts based on bispectral index monitoring or minimum alveolar concentration for the prevention of intraoperative awareness

    Directory of Open Access Journals (Sweden)

    Avidan Michael S

    2009-11-01

    Full Text Available Abstract Background The incidence of intraoperative awareness with explicit recall is 1-2/1000 cases in the United States. The Bispectral Index monitor is an electroencephalographic method of assessing anesthetic depth that has been shown in one prospective study to reduce the incidence of awareness in the high-risk population. In the B-Aware trial, the number needed to treat in order to prevent one case of awareness in the high-risk population was 138. Since the number needed to treat and the associated cost of treatment would be much higher in the general population, the efficacy of the Bispectral Index monitor in preventing awareness in all anesthetized patients needs to be clearly established. This is especially true given the findings of the B-Unaware trial, which demonstrated no significant difference between protocols based on the Bispectral Index monitor or minimum alveolar concentration for the reduction of awareness in high risk patients. Methods/Design To evaluate efficacy in the general population, we are conducting a prospective, randomized, controlled trial comparing the Bispectral Index monitor to a non-electroencephalographic gauge of anesthetic depth. The total recruitment for the study is targeted for 30,000 patients at both low and high risk for awareness. We have developed a novel algorithm that is capable of real-time analysis of our electronic perioperative information system. In one arm of the study, anesthesia providers will receive an electronic page if the Bispectral Index value is >60. In the other arm of the study, anesthesia providers will receive a page if the age-adjusted minimum alveolar concentration is Discussion Awareness during general anesthesia is a persistent problem and the role of the Bispectral Index monitor in its prevention is still unclear. The Michigan Awareness Control Study is the largest prospective trial of awareness prevention ever conducted. Trial Registration Clinical Trial NCT00689091

  12. Adsorption and leaching of novel fungicide pyraoxystrobin on soils by 14C tracing method.

    Science.gov (United States)

    Liu, Xunyue; Wu, Huiming; Hu, Tingting; Chen, Xia; Ding, Xingcheng

    2018-01-19

    Pyraoxystrobin, (E)-2-(2-((3-(4-chlorophenyl)-1-methyl-1H-pyrazole-5-yloxy)methyl)phenyl)-3-methoxyacrylate, is a newly developed strobilurin fungicide with high antifungal efficiency. It has high potential to enter soil environments that might subsequently impact surface and groundwater. Therefore, 14 C-labeled pyraoxystrobin was used as a tracer to study the adsorption/desorption and migration behavior of this compound under laboratory conditions in three typical agricultural soils. The adsorption isotherms conformed with the Freundlich equation. Single factor analysis showed that organic matter content was the most important factor influencing the adsorption. The highest adsorption level was measured in soil with low pH and high organic carbon content. Once adsorbed, only 2.54 to 6.41% of the adsorbed compound could be desorbed. In addition, the mobility results from thin-layer chromatography and column leaching studies showed that it might be safe to use pyraoxystrobin as a fungicide without causing groundwater pollution from both runoff and leaching, which might be attributed to its strong hydrophobicity. High organic matter content enhanced pyraoxystrobin adsorption and desorption because of the rule of similarity (lipid solubility). In the column leaching study, 95.02% (minimum value) of the applied 14 C remained within the upper 4.0-cm layer after 60 days.

  13. Impact of Fungicide Residues on Polymerase Chain Reaction and on Yeast Metabolism

    Directory of Open Access Journals (Sweden)

    Gildo Almeida da Silva

    Full Text Available ABSTRACT The indiscriminate use of pesticides on grape crops is harmful for consumers´ healthin “in natura” consumption and in the ingestion of wine and grape juice. During winemaking, a rapid and efficient fermentation stage is critical to avoid proliferation of contaminating microorganisms and to guarantee the product´s quality. Polymerase chain reaction (PCR has the advantage of detecting these contaminants in the early stages of fermentation. However,this enzymatic reaction may also be susceptible to specific problems, reducing its efficiency. Agricultural practices, such as fungicide treatments, may be a source of PCR inhibiting factors and may also interfere in the normal course of fermentation.The action of the pesticides captan and folpet on PCR and on yeast metabolism was evaluated, once these phthalimide compounds are widely employed in Brazilian vineyards. DNA amplification was only observed at 75 and 37.5 µg/mL of captan concentrations, whereas with folpet, amplification was observed only in the two lowest concentrations tested (42.2 and 21.1µg/mL.Besides the strong inhibition on Taq polymerase activity, phthalimides also inhibited yeast metabolism at all concentrations analyzed.Grape must containing captan and folpet residues could not be transformed into wine due to stuck fermentation caused by the inhibition of yeast metabolism. Non-compliance with the waiting period for phthalimide fungicides may result in financial liabilities to the viticulture sector.The use of yeasts with high fungicide sensitivity should be selected for must fermentation as a strategy for sustainable wine production and to assure that products comply with health and food safety standards.

  14. The effect of the fungicide captan on Saccharomyces cerevisiae and wine fermentation

    Directory of Open Access Journals (Sweden)

    Scariot Fernando J.

    2016-01-01

    Full Text Available Fungicides, particularly those used during grape maturation, as captan, can affect the natural yeast population of grapes, and can reach grape must affecting wine fermentation. The objective of the present work was to study the effect of captan on the viability and fermentative behavior of S. cerevisiae. S. cerevisiae (BY4741 on exponential phase was treated with captan (0 to 40 μM for different periods, and their cell viability analyzed. Cell membrane integrity, thiols concentration, and reactive oxygen species (ROS accumulation was determined. The fermentation experiments were conducted in synthetic must using wine yeast strain Y904. The results showed that under aerobic conditions, 20 μM of captan reduce 90% of yeast viability in 6 hours. Captan treated cells exhibited alteration of membrane integrity, reduction of thiol compounds and increase in intracellular ROS concentration, suggesting a necrotic and pro-oxidant activity of the fungicide. Fermentative experiments showed that concentrations above 2.5 μM captan completely inhibited fermentation, while a dose dependent fermentation delay associated with the reduction of yeast viability was detected in sub-inhibitory concentrations. Petit mutants increase was also observed. In conclusion, the captan induces yeast necrotic cell death on both aerobic and anaerobic conditions causing fermentation delay and/or sucking fermentations.

  15. Strobilurin fungicides induce changes in photosynthetic gas exchange that do not improve water use efficiency of plants grown under conditions of water stress.

    Science.gov (United States)

    Nason, Mark A; Farrar, John; Bartlett, David

    2007-12-01

    The effects of five strobilurin (beta-methoxyacrylate) fungicides and one triazole fungicide on the physiological parameters of well-watered or water-stressed wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and soya (Glycine max Merr.) plants were compared. Water use efficiency (WUE) (the ratio of rate of transpiration, E, to net rate of photosynthesis, A(n)) of well-watered wheat plants was improved slightly by strobilurin fungicides, but was reduced in water-stressed plants, so there is limited scope for using strobilurins to improve the water status of crops grown under conditions of drought. The different strobilurin fungicides had similar effects on plant physiology but differed in persistence and potency. When applied to whole plants using a spray gun, they reduced the conductance of water through the epidermis (stomatal and cuticular transpiration), g(sw), of leaves. Concomitantly, leaves of treated plants had a lower rate of transpiration, E, a lower intercellular carbon dioxide concentration, c(i), and a lower net rate of photosynthesis, A(n), compared with leaves of control plants or plants treated with the triazole. The mechanism for the photosynthetic effects is not known, but it is hypothesised that they are caused either by strobilurin fungicides acting directly on ATP production in guard cell mitochondria or by stomata responding to strobilurin-induced changes in mesophyll photosynthesis. The latter may be important since, for leaves of soya plants, the chlorophyll fluorescence parameter F(v)/F(m) (an indication of the potential quantum efficiency of PSII photochemistry) was reduced by strobilurin fungicides. It is likely that the response of stomata to strobilurin fungicides is complex, and further research is required to elucidate the different biochemical pathways involved. Copyright (c) 2007 Society of Chemical Industry.

  16. Inhibitory effects of azole-type fungicides on interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

    Science.gov (United States)

    Kojima, Hiroyuki; Muromoto, Ryuta; Takahashi, Miki; Takeuchi, Shinji; Takeda, Yukimasa; Jetten, Anton M.; Matsuda, Tadashi

    2013-01-01

    The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. However, it remains unclear whether environmental chemicals, including pesticides, have agonistic and/or antagonistic activity against RORα/γ. In this study, we investigated the RORα/γ activity of several azole-type fungicides, and the effects of these fungicides on the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In the ROR-reporter gene assays, five azole-type fungicides (imibenconazole, triflumizole, hexaconazole, tetraconazole and imazalil) suppressed RORα- and/or RORγ-mediated transcriptional activity as did benzenesulphonamide T0901317, a ROR inverse agonist and a liver X receptor (LXR) agonist. In particular, imibenconazole, triflumizole and hexaconazole showed RORγ inverse agonistic activity at concentrations of 10−6 M. However, unlike T0901317, these fungicides failed to show any LXRα/β agonistic activity. Next, five azole-type fungicides, showing ROR inverse agonist activity, were tested on IL-17 mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin. The quantitative RT-PCR analysis revealed that these fungicides suppressed the expression of IL-17 mRNA without effecting RORα and RORγ mRNA levels. In addition, the inhibitory effect of imibenconazole as well as that of T0901317 was absorbed in RORα/γ-knocked down EL4 cells. Taken together, these results suggest that some azole-type fungicides inhibit IL-17 production via RORα/γ. This also provides the first evidence that environmental chemicals can act as modulators of IL-17 expression in immune cells. PMID:22289359

  17. Occurrence of fungicides and other pesticides in surface water, groundwater, and sediment from three targeted-use areas in the United States, 2009

    Science.gov (United States)

    Orlando, James L.; Smalling, Kelly L.; Reilly, Timothy J.; Boehlke, Adam; Meyer, Michael T.; Kuivila, Kathryn

    2013-01-01

    Surface-water, groundwater, and suspended- and bedsediment samples were collected in three targeted-use areas in the United States where potatoes were grown during 2009 and analyzed for an extensive suite of fungicides and other pesticides by gas chromatograph/mass spectrometry and liquid chromatography with tandem mass spectrometry. Fungicides were detected in all environmental matrices sampled during the study. The most frequently detected fungicides were azoxystrobin, boscalid, chlorothalonil, and pyraclostrobin. Other pesticides that were detected frequently included amino phosphonic acid (AMPA), atrazine, metolaclor, and the organochlorine insecticide p,p’-DDT and its degradates p,p’-DDD and p,p’-DDE. A greater number of pesticides were detected in surface water relative to the other environmental matrices sampled, and at least one pesticide was detected in 62 of the 63 surfacewater samples. The greatest numbers of pesticides and the maximum observed concentrations for most pesticides were measured in surface-water samples from Idaho. In eight surface- water samples (six from Idaho and two from Wisconsin), concentrations of bifenthrin, metolachlor, or malathion exceeded U.S. Environmental Protection Agency freshwater aquatic-life benchmarks for chronic toxicity to invertebrates. Thirteen pesticides, including seven fungicides, were detected in groundwater samples. Shallow groundwater samples collected beneath recently harvested potato fields contained more pesticides and had higher concentrations of pesticides than samples collected from other groundwater sources sampled during the study. Generally, pesticide concentrations were lower in groundwater samples than in surfacewater or sediment samples, with the exception of the fungicide boscalid, which was found to have its highest concentration in a shallow groundwater sample collected in Wisconsin. Thirteen pesticides, including four fungicides, were detected in suspended-sediment samples. The most

  18. In-Vitro Inhibition of Pythium ultimum, Fusarium graminearum, and Rhizoctonia solani by a Stabilized Lactoperoxidase System alone and in Combination with Synthetic Fungicides

    Directory of Open Access Journals (Sweden)

    Zachariah R. Hansen

    2017-11-01

    Full Text Available Advances in enzyme stabilization and immobilization make the use of enzymes for industrial applications increasingly feasible. The lactoperoxidase (LPO system is a naturally occurring enzyme system with known antimicrobial activity. Stabilized LPO and glucose oxidase (GOx enzymes were combined with glucose, potassium iodide, and ammonium thiocyanate to create an anti-fungal formulation, which inhibited in-vitro growth of the plant pathogenic oomycete Pythium ultimum, and the plant pathogenic fungi Fusarium graminearum and Rhizoctonia solani. Pythium ultimum was more sensitive than F. graminearum and R. solani, and was killed at LPO and GOx concentrations of 20 nM and 26 nM, respectively. Rhizoctonia solani and F. graminearum were 70% to 80% inhibited by LPO and GOx concentrations of 242 nM and 315 nM, respectively. The enzyme system was tested for compatibility with five commercial fungicides as co-treatments. The majority of enzyme + fungicide co-treatments resulted in additive activity. Synergism ranging from 7% to 36% above the expected additive activity was observed when P. ultimum was exposed to the enzyme system combined with Daconil® (active ingredient (AI: chlorothalonil 29.6%, GardenTech, Lexington, KY, USA, tea tree oil, and mancozeb at select fungicide concentrations. Antagonism was observed when the enzyme system was combined with Tilt® (AI: propiconazole 41.8%, Syngenta, Basel, Switzerland at one fungicide concentration, resulting in activity 24% below the expected additive activity at that concentration.

  19. Fungicidal efficacy of various honeys against fluconazole-resistant Candida species isolated from HIV+ patients with candidiasis.

    Science.gov (United States)

    Shokri, H; Sharifzadeh, A

    2017-06-01

    Honey is well known to possess a broad spectrum of activity against medically important organisms. The purpose of this study was to assess the antifungal activity of different honeys against 40 fluconazole (FLU) resistant Candida species, including Candida albicans (C. albicans), Candida glabrata, Candida krusei and Candida tropicalis. Three honey samples were collected from northern (Mazandaran, A), southern (Hormozgan, B) and central (Lorestan, C) regions of Iran. A microdilution technique based on the CLSI, M27-A2 protocol was employed to compare the susceptibility of honeys "A", "B" and "C" against different pathogenic Candida isolates. The results showed that different Candida isolates were resistant to FLU, ranging from 64μg/mL to 512μg/mL. All of the honeys tested had antifungal activities against FLU-resistant Candida species, ranging from 20% to 56.25% (v/v) and 25% to 56.25% (v/v) for minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs), respectively. Honey "A" (MIC: 31.59%, v/v) showed higher anti-Candida activity than honey "B" (MIC: 35.99%, v/v) and honey "C" (MIC: 39.2%, v/v). No statistically significant differences were observed among the mean MIC values of the honey samples (P>0.05). The order of overall susceptibility of Candida species to honey samples were; C. krusei>C. glabrata>C. tropicalis>C. albicans (P>0.05). In addition, the mean MICs of Candida strains isolated from the nail, vagina and oral cavity were 33.68%, 36.44% and 39.89%, respectively, and were not significantly different (P>0.05). Overall, varying susceptibilities to the anti-Candida properties of different honeys were observed with four FLU-resistant species of Candida. Further research is needed to assess the efficacy of honey as an inhibitor of candidal growth in clinical trials. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  20. The Effect of Fungicide Residues and Yeast Assimilable Nitrogen on Fermentation Kinetics and H2S Production during Cider Fermentation

    OpenAIRE

    Boudreau IV, Thomas Francis

    2016-01-01

    The Virginia cider industry has grown rapidly in the past decade, and demands research-based recommendations for cider fermentation. This study evaluated relationships between the unique chemistry of apples and production of hydrogen sulfide (H2S) in cider fermentations. Yeast assimilable nitrogen (YAN) concentration and composition and residual fungicides influence H2S production by yeast during fermentation, but these factors have to date only been studied in wine grape fermentations. This ...

  1. Potential Mechanisms Underlying Response to Effects of the Fungicide Pyrimethanil from Gene Expression Profiling inSaccharomyces cerevisiae

    OpenAIRE

    Gil, Fátima N.; Becker, Jörg D.; Viegas, Cristina A.

    2014-01-01

    Pyrimethanil is a fungicide mostly applied in vineyards. When misused, residue levels detected in grape must or in the environment may be of concern. The present work aimed to analyze mechanisms underlying response to deleterious effects of pyrimethanil in the eukaryotic model Saccharomyces cerevisiae. Pyrimethanil concentration-dependent effects at phenotypic (inhibition of growth) and transcriptomic levels were examined. For transcriptional profiling, analysis focused on two sublethal expos...

  2. Fungicidal and anti-aflatoxigenic effects of the essential oil of Cymbopogon citratus (DC.) Stapf. (lemongrass) against Aspergillus flavus Link. isolated from stored rice.

    Science.gov (United States)

    Paranagama, P A; Abeysekera, K H T; Abeywickrama, K; Nugaliyadde, L

    2003-01-01

    To develop a natural fungicide against aflatoxigenic fungi, to protect stored rice, using the essential oil of lemongrass. Aspergillus flavus Link. was isolated from stored rice and identified as an aflatoxigenic strain. Lemongrass oil was tested against A. flavus and the test oil was fungistatic and fungicidal against the test pathogen at 0.6 and 1.0 mg ml(-1), respectively. Aflatoxin production was completely inhibited at 0.1 mg ml(-1). The results obtained from the thin layer chromatographic bioassay and gas chromatography indicated citral a and b as the fungicidal constituents in lemongrass oil. During the fumigant toxicity assay of lemongrass oil, the sporulation and the mycelial growth of the test pathogen were inhibited at the concentrations of 2.80 and 3.46 mg ml(-1), respectively. Lemongrass oil could be used to manage aflatoxin formation and fungal growth of A. flavus in stored rice. Currently, fungicides are not used to control fungal pests or mycotoxin production on stored rice. Rice treated with the essential oil of lemongrass could be used to manage fungal pests as well as the insect pests in stored rice. The essential oil is chemically safe and acceptable to consumers, as synthetic chemical fungicides can cause adverse health effects to consumers.

  3. Nanosulfur: A Potent Fungicide Against Food Pathogen, Aspergillus niger

    International Nuclear Information System (INIS)

    Choudhury, Samrat Roy; Goswami, Arunava; Nair, Kishore K.; Kumar, Rajesh; Gopal, Madhuban; Devakumar, C.; Gogoi, Robin; Srivastava, Chitra; Subhramanyam, B. S.

    2010-01-01

    Elemental sulfur (S 0 ), man's oldest eco-friendly fungicide for curing fungal infections in plants and animals, is registered in India as a non-systemic and contact fungicide. However due to its high volume requirement, Indian agrochemical industry and farmers could not effectively use this product till date. We hypothesize that intelligent nanoscience applications might increase the visibility of nanosulfur in Indian agriculture as a potent and eco-safe fungicide. Sulfur nanoparticles (NPs) were synthesized bottom-up via a liquid synthesis method with average particle size in the range of 50-80 nm and the shapes of the NPs were spherical. A comparative study of elemental and nano-sulfur produced has been tested against facultative fungal food pathogen, Aspergillus niger. Results showed that nanosulfur is more efficacious than its elemental form.

  4. Reduced fungicide doses in cereals: Which parameters to consider?

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup

    2015-01-01

    dose. In spring barley the economically optimum input can vary from 0-2 treatments with a total fungicide use equivalent to 0.25 to 0.5 times the recommended dose. Applying reducing rates should never result in significant inferior control and economical yield losses. A recent review concluded......, the pathogen, disease pressure and timing of treatments. Certain diseases are known to require higher input (40- 75% rates) for achieving satisfactory control – this is the case for Septoria leaf blight, Rhynchosporium net blotch and Fusarium head blight, whereas most rust diseases generally have been found...... on well-established disease attack. Rates also have to be adjusted according to canopy structures. Early timing on a small canopy requires less fungicide than a full canopy around heading. The knowledge gathered concerning fungicide rates has led to great focus on the importance of optimizing timing...

  5. Nanosulfur: A Potent Fungicide Against Food Pathogen, Aspergillus niger

    Science.gov (United States)

    Choudhury, Samrat Roy; Nair, Kishore K.; Kumar, Rajesh; Gogoi, Robin; Srivastava, Chitra; Gopal, Madhuban; Subhramanyam, B. S.; devakumar, C.; Goswami, Arunava

    2010-10-01

    Elemental sulfur (S0), man's oldest eco-friendly fungicide for curing fungal infections in plants and animals, is registered in India as a non-systemic and contact fungicide. However due to its high volume requirement, Indian agrochemical industry and farmers could not effectively use this product till date. We hypothesize that intelligent nanoscience applications might increase the visibility of nanosulfur in Indian agriculture as a potent and eco-safe fungicide. Sulfur nanoparticles (NPs) were synthesized bottom-up via a liquid synthesis method with average particle size in the range of 50-80 nm and the shapes of the NPs were spherical. A comparative study of elemental and nano-sulfur produced has been tested against facultative fungal food pathogen, Aspergillus niger. Results showed that nanosulfur is more efficacious than its elemental form.

  6. The impact of the fungicide fenpropimorph (Corbel) on bacterivorous and fungivorous protozoa in soil

    DEFF Research Database (Denmark)

    Ekelund, Flemming

    1999-01-01

    1. The ability of indigenous soil protozoa to survive and multiply when exposed to various concentrations of the fungicide fenpropimorph was investigated. The number of protozoan taxa in relation to biocide concentration was examined in enrichment cultures. The population dynamics of bacterivorous...... and fungivorous protozoa, hyphal forming units, and respiration activity were followed in soil microcosms amended with glucose and various concentrations of fenpropimorph. 2. The average number of flagellate taxa detected in 50-mg portions of air-dried soil declined from 12 to zero with fenpropimorph...... as in systems with glucose only; however, soil respiration was significantly impeded in microcosm systems with a low pesticide content and stimulated in systems with a high pesticide content. 4. Bacterivorous protozoa (naked amoebae and heterotrophic flagellates) were affected at all tested concentrations (074...

  7. Triazole fungicide tebuconazole disrupts human placental trophoblast cell functions

    International Nuclear Information System (INIS)

    Zhou, Jinghua; Zhang, Jianyun; Li, Feixue; Liu, Jing

    2016-01-01

    Highlights: • Tebuconazole (TEB) inhibited the proliferation of human placental trophoblasts. • TEB changed cell cycle distribution of G1 and G2 phases of trophoblasts. • TEB induced apoptosis of trophoblasts via mitochondrial pathway. • TEB decreased the invasive and migratory capacities of trophoblasts. • TEB altered the mRNA levels of key regulatory genes in trophoblasts - Abstract: Triazole fungicides are one of the top ten classes of current-use pesticides. Although exposure to triazole fungicides is associated with reproductive toxicity in mammals, limited information is available regarding the effects of triazole fungicides on human placental trophoblast function. Tebuconazole (TEB) is a common triazole fungicide that has been extensively used for fungi control. In this work, we showed that TEB could reduce cell viability, disturb normal cell cycle distribution and induce apoptosis of human placental trophoblast cell line HTR-8/SVneo (HTR-8). Bcl-2 protein expression decreased and the level of Bax protein increased after TEB treatment in HTR-8 cells. The results demonstrated that this fungicide induced apoptosis of trophoblast cells via mitochondrial pathway. Importantly, we found that the invasive and migratory capacities of HTR-8 cells decreased significantly after TEB administration. TEB altered the expression of key regulatory genes involved in the modulation of trophoblast functions. Taken together, TEB suppressed human trophoblast invasion and migration through affecting the expression of protease, hormones, angiogenic factors, growth factors and cytokines. As the invasive and migratory abilities of trophoblast are essential for successful placentation and fetus development, our findings suggest a potential risk of triazole fungicides to human pregnancy.

  8. Triazole fungicide tebuconazole disrupts human placental trophoblast cell functions

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jinghua [Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Education, Zhejiang University, Hangzhou 310058 (China); Zhang, Jianyun [Research Center for Air Pollution and Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China); Li, Feixue [Zhejiang Key Laboratory of Organ Development and Regeneration, Institute of Developmental and Regenerative Biology, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036 (China); Liu, Jing, E-mail: jliue@zju.edu.cn [Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Education, Zhejiang University, Hangzhou 310058 (China); Research Center for Air Pollution and Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058 (China)

    2016-05-05

    Highlights: • Tebuconazole (TEB) inhibited the proliferation of human placental trophoblasts. • TEB changed cell cycle distribution of G1 and G2 phases of trophoblasts. • TEB induced apoptosis of trophoblasts via mitochondrial pathway. • TEB decreased the invasive and migratory capacities of trophoblasts. • TEB altered the mRNA levels of key regulatory genes in trophoblasts - Abstract: Triazole fungicides are one of the top ten classes of current-use pesticides. Although exposure to triazole fungicides is associated with reproductive toxicity in mammals, limited information is available regarding the effects of triazole fungicides on human placental trophoblast function. Tebuconazole (TEB) is a common triazole fungicide that has been extensively used for fungi control. In this work, we showed that TEB could reduce cell viability, disturb normal cell cycle distribution and induce apoptosis of human placental trophoblast cell line HTR-8/SVneo (HTR-8). Bcl-2 protein expression decreased and the level of Bax protein increased after TEB treatment in HTR-8 cells. The results demonstrated that this fungicide induced apoptosis of trophoblast cells via mitochondrial pathway. Importantly, we found that the invasive and migratory capacities of HTR-8 cells decreased significantly after TEB administration. TEB altered the expression of key regulatory genes involved in the modulation of trophoblast functions. Taken together, TEB suppressed human trophoblast invasion and migration through affecting the expression of protease, hormones, angiogenic factors, growth factors and cytokines. As the invasive and migratory abilities of trophoblast are essential for successful placentation and fetus development, our findings suggest a potential risk of triazole fungicides to human pregnancy.

  9. Control of sugar beet powdery mildew with strobilurin fungicides

    Directory of Open Access Journals (Sweden)

    Karaoglanidis George S.

    2006-01-01

    Full Text Available Powdery mildew, caused by Erysiphe betae is a major foliar disease of sugar beet in areas with dry and relatively warm weather conditions throughout the world. In the present study, four fungicides belonging to the relatively new class of strobilurin fungicides, azoxystrobin, kresoxim-methyl pyraclostrobin and trifloxystrobin were evaluated in three different application doses (100, 150 and 200 mg a.i. ha–1 during 2003-2004 for the control of the disease. Among the four strobilurin fungicides tested trifloxystrobin and kresoxim-methyl were the most effective with control efficiency values higher than 94% compared to the control treatment even when applied at lower application dose of 100 mg a.i. ha–1. Azoxystrobin and pyraclostrobin showed a poor to modest activity against the disease even when applied at the highest application dose of 200 μg a.i. ha–1. Disease severity, in terms of AUDPC values was significantly correlated to decreased root yield, while no significant correlation existed among disease severity and sugar content of the roots or sucrose yield. In addition, the efficiency of tank mixtures of four strobilurin fungicides applied at 100 μg a.i. ha–1 with two sterol demethylation - inhibiting fungicides (DMIs, difenoconazole and cyproconazole applied at 62.5 and 25 mg a.i. ha–1, respectively, was evaluated. The mixtures of azoxystrobin and pyraclostrobin with either difenoconazole or cyproconazole provided a better control efficiency compared to the single application of each mixture partner, while the tank mixtures of trifloxystrobin and kresoxim-methyl with either difenoconazole or cyproconazole provided a better control efficiency compared to single application of difenoconazole or cyproconazole and similar control efficiency compared to the efficiency obtained by single application of the strobilurin fungicides.

  10. Method validation for strobilurin fungicides in cereals and fruit

    DEFF Research Database (Denmark)

    Christensen, Hanne Bjerre; Granby, Kit

    2001-01-01

    Strobilurins are a new class of fungicides that are active against a broad spectrum of fungi. In the present work a GC method for analysis of strobilurin fungicides was validated. The method was based on extraction with ethyl acetate/cyclohexane, clean-up by gel permeation chromatography (GPC......) and determination of the content by gas chromatography (GC) with electron capture (EC-), nitrogen/phosphorous (NP-), and mass spectrometric (MS-) detection. Three strobilurins, azoxystrobin, kresoxim-methyl and trifloxystrobin were validated on three matrices, wheat, apple and grapes. The validation was based...

  11. Mode of action of the phenylpyrrole fungicide fenpiclonil in Fusarium sulphureum

    NARCIS (Netherlands)

    Jespers, A.B.K.

    1994-01-01

    In the last few decades, plant disease control has become heavily dependent on fungicides. Most modem fungicides were discovered by random synthesis and empirical optimization of lead structures. In general, these fungicides have specific modes of action and meet modem enviromnental

  12. Sensitivity of macroinvertebrates to carbendazim under semi-field conditions in Thailand: Implications for the use of temperate toxicity data in a tropical risk assessment of fungicides

    NARCIS (Netherlands)

    Daam, M.A.; Satapornvanit, K.; Brink, van den P.J.; Nogueira, A.J.A.

    2009-01-01

    The present paper discusses the fate of the fungicide carbendazim (nominal concentrations: 0, 3.3, 33, 100 and 1000 µg L-1) and its effects on the macroinvertebrate community in outdoor microcosms set up in Thailand. Fate and threshold values were subsequently compared with those noted in temperate

  13. The fungicidal and phytotoxic properties of benomyl and PPM in supplemented agar media supporting transgenic arabidopsis plants for a Space Shuttle flight experiment

    Science.gov (United States)

    Paul, A. L.; Semer, C.; Kucharek, T.; Ferl, R. J.

    2001-01-01

    Fungal contamination is a significant problem in the use of sucrose-enriched agar-based media for plant culture, especially in closed habitats such as the Space Shuttle. While a variety of fungicides are commercially available, not all are equal in their effectiveness in inhibiting fungal contamination. In addition, fungicide effectiveness must be weighed against its phytotoxicity and in this case, its influence on transgene expression. In a series of experiments designed to optimize media composition for a recent shuttle mission, the fungicide benomyl and the biocide "Plant Preservative Mixture" (PPM) were evaluated for effectiveness in controlling three common fungal contaminants, as well as their impact on the growth and development of arabidopsis seedlings. Benomyl proved to be an effective inhibitor of all three contaminants in concentrations as low as 2 ppm (parts per million) within the agar medium, and no evidence of phytotoxicity was observed until concentrations exceeded 20 ppm. The biocide mix PPM was effective as a fungicide only at concentrations that had deleterious effects on arabidopsis seedlings. As a result of these findings, a concentration of 3 ppm benomyl was used in the media for experiment PGIM-01 which flew on shuttle Columbia mission STS-93 in July 1999.

  14. Inhibitory effects of azole-type fungicides on interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

    Energy Technology Data Exchange (ETDEWEB)

    Kojima, Hiroyuki, E-mail: kojima@iph.pref.hokkaido.jp [Hokkaido Institute of Public Health, Kita-19, Nishi-12, Kita-ku, Sapporo 060-0819 (Japan); Muromoto, Ryuta; Takahashi, Miki [Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812 (Japan); Takeuchi, Shinji [Hokkaido Institute of Public Health, Kita-19, Nishi-12, Kita-ku, Sapporo 060-0819 (Japan); Takeda, Yukimasa; Jetten, Anton M. [National Institute of Environmental Health Sciences, National Institutes of Health, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709 (United States); Matsuda, Tadashi [Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-12, Nishi-6, Kita-ku, Sapporo 060-0812 (Japan)

    2012-03-15

    The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. However, it remains unclear whether environmental chemicals, including pesticides, have agonistic and/or antagonistic activity against RORα/γ. In this study, we investigated the RORα/γ activity of several azole-type fungicides, and the effects of these fungicides on the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In the ROR-reporter gene assays, five azole-type fungicides (imibenconazole, triflumizole, hexaconazole, tetraconazole and imazalil) suppressed RORα- and/or RORγ-mediated transcriptional activity as did benzenesulphonamide T0901317, a ROR inverse agonist and a liver X receptor (LXR) agonist. In particular, imibenconazole, triflumizole and hexaconazole showed RORγ inverse agonistic activity at concentrations of 10{sup −6} M. However, unlike T0901317, these fungicides failed to show any LXRα/β agonistic activity. Next, five azole-type fungicides, showing ROR inverse agonist activity, were tested on IL-17 mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin. The quantitative RT-PCR analysis revealed that these fungicides suppressed the expression of IL-17 mRNA without effecting RORα and RORγ mRNA levels. In addition, the inhibitory effect of imibenconazole as well as that of T0901317 was absorbed in RORα/γ-knocked down EL4 cells. Taken together, these results suggest that some azole-type fungicides inhibit IL-17 production via RORα/γ. This also provides the first evidence that environmental chemicals can act as modulators of IL-17 expression in immune cells. -- Highlights: ► Nuclear receptors, RORα and RORγ, are key regulators of Th17 cell differentiation. ► Five azole-type fungicides act as RORα/γ inverse agonists. ► These fungicides

  15. Inhibitory effects of azole-type fungicides on interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

    International Nuclear Information System (INIS)

    Kojima, Hiroyuki; Muromoto, Ryuta; Takahashi, Miki; Takeuchi, Shinji; Takeda, Yukimasa; Jetten, Anton M.; Matsuda, Tadashi

    2012-01-01

    The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. However, it remains unclear whether environmental chemicals, including pesticides, have agonistic and/or antagonistic activity against RORα/γ. In this study, we investigated the RORα/γ activity of several azole-type fungicides, and the effects of these fungicides on the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In the ROR-reporter gene assays, five azole-type fungicides (imibenconazole, triflumizole, hexaconazole, tetraconazole and imazalil) suppressed RORα- and/or RORγ-mediated transcriptional activity as did benzenesulphonamide T0901317, a ROR inverse agonist and a liver X receptor (LXR) agonist. In particular, imibenconazole, triflumizole and hexaconazole showed RORγ inverse agonistic activity at concentrations of 10 −6 M. However, unlike T0901317, these fungicides failed to show any LXRα/β agonistic activity. Next, five azole-type fungicides, showing ROR inverse agonist activity, were tested on IL-17 mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin. The quantitative RT-PCR analysis revealed that these fungicides suppressed the expression of IL-17 mRNA without effecting RORα and RORγ mRNA levels. In addition, the inhibitory effect of imibenconazole as well as that of T0901317 was absorbed in RORα/γ-knocked down EL4 cells. Taken together, these results suggest that some azole-type fungicides inhibit IL-17 production via RORα/γ. This also provides the first evidence that environmental chemicals can act as modulators of IL-17 expression in immune cells. -- Highlights: ► Nuclear receptors, RORα and RORγ, are key regulators of Th17 cell differentiation. ► Five azole-type fungicides act as RORα/γ inverse agonists. ► These fungicides suppress

  16. Widespread contamination of wildflower and bee-collected pollen with complex mixtures of neonicotinoids and fungicides commonly applied to crops.

    Science.gov (United States)

    David, Arthur; Botías, Cristina; Abdul-Sada, Alaa; Nicholls, Elizabeth; Rotheray, Ellen L; Hill, Elizabeth M; Goulson, Dave

    2016-03-01

    There is considerable and ongoing debate as to the harm inflicted on bees by exposure to agricultural pesticides. In part, the lack of consensus reflects a shortage of information on field-realistic levels of exposure. Here, we quantify concentrations of neonicotinoid insecticides and fungicides in the pollen of oilseed rape, and in pollen of wildflowers growing near arable fields. We then compare this to concentrations of these pesticides found in pollen collected by honey bees and in pollen and adult bees sampled from bumble bee colonies placed on arable farms. We also compared this with levels found in bumble bee colonies placed in urban areas. Pollen of oilseed rape was heavily contaminated with a broad range of pesticides, as was the pollen of wildflowers growing nearby. Consequently, pollen collected by both bee species also contained a wide range of pesticides, notably including the fungicides carbendazim, boscalid, flusilazole, metconazole, tebuconazole and trifloxystrobin and the neonicotinoids thiamethoxam, thiacloprid and imidacloprid. In bumble bees, the fungicides carbendazim, boscalid, tebuconazole, flusilazole and metconazole were present at concentrations up to 73nanogram/gram (ng/g). It is notable that pollen collected by bumble bees in rural areas contained high levels of the neonicotinoids thiamethoxam (mean 18ng/g) and thiacloprid (mean 2.9ng/g), along with a range of fungicides, some of which are known to act synergistically with neonicotinoids. Pesticide exposure of bumble bee colonies in urban areas was much lower than in rural areas. Understanding the effects of simultaneous exposure of bees to complex mixtures of pesticides remains a major challenge. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The interactive effect of fungicide residues and yeast assimilable nitrogen on fermentation kinetics and hydrogen sulfide production during cider fermentation.

    Science.gov (United States)

    Boudreau, Thomas F; Peck, Gregory M; O'Keefe, Sean F; Stewart, Amanda C

    2017-01-01

    Fungicide residues on fruit may adversely affect yeast during cider fermentation, leading to sluggish or stuck fermentation or the production of hydrogen sulfide (H 2 S), which is an undesirable aroma compound. This phenomenon has been studied in grape fermentation but not in apple fermentation. Low nitrogen availability, which is characteristic of apples, may further exacerbate the effects of fungicides on yeast during fermentation. The present study explored the effects of three fungicides: elemental sulfur (S 0 ) (known to result in increased H 2 S in wine); fenbuconazole (used in orchards but not vineyards); and fludioxonil (used in post-harvest storage of apples). Only S 0 led to increased H 2 S production. Fenbuconazole (≥0.2 mg L -1 ) resulted in a decreased fermentation rate and increased residual sugar. An interactive effect of yeast assimilable nitrogen (YAN) concentration and fenbuconazole was observed such that increasing the YAN concentration alleviated the negative effects of fenbuconazole on fermentation kinetics. Cidermakers should be aware that residual fenbuconazole (as low as 0.2 mg L -1 ) in apple juice may lead to stuck fermentation, especially when the YAN concentration is below 250 mg L -1 . These results indicate that fermentation problems attributed to low YAN may be caused or exacerbated by additional factors such as fungicide residues, which have a greater impact on fermentation performance under low YAN conditions. © 2016 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2016 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  18. Bioassay and characterization of soil microorganisms involved in the biodegradation of the fungicide, metalaxyl

    International Nuclear Information System (INIS)

    Bailey, A.M.

    1985-01-01

    A sensitive bioassay was developed to detect low concentrations of metalaxyl in soils. The quantitative estimation of metalaxyl in soils was based on a significant positive relationship between the radial growth of Phytophthora boehmeriae and the log concentration of the fungicide in the agar. The isolate of P. boehmeriae was chosen for its sensitivity to metalaxyl as manifested in a linear growth response on cornmeal agar over a range of 2 to 30 ng/ml. The sensitivity and quantitative nature of the bioassay was confirmed by comparison with data obtained by using 14 C-metalaxyl. Metabolism of metalaxyl was detected in three of five avocado soils that had repeated applications of the fungicide over 2-5 yr. The average disappearance of metalaxyl was 28 days, and in the most active soils was 14 days. The composition and level of the microbial populations of soils, either active or inactive in the breakdown of metalaxyl, did not differ. Fungal and bacterial microflora recovered from these two soils by use of either selective media or filtration techniques were capable of metabolizing metalaxyl over a 45-day period

  19. Cytotoxicity of the dicarboximide fungicides, vinclozolin and iprodione, in rat hepatoma-derived Fa32 cells.

    Science.gov (United States)

    Dierickx, Paul J

    2004-10-01

    Dicarboximide fungicides are widely used to control various fungal species. Their primary action is not known, due to a lack of knowledge concerning the mechanism of action of the dicarboximide group. The cytotoxicities of vinclozolin and iprodione in rat hepatoma-derived Fa32 cells were investigated. Cytotoxicity was measured by neutral red uptake inhibition after treatment for 24 hours. Iprodione was more toxic than vinclozolin. Vinclozolin was less toxic in glutathione-depleted cells than in control cells. This was also true for iprodione at lower concentrations, but iprodione became more toxic at higher concentrations. Both the fungicides increased the endogenous glutathione content by 20% after 1 hour. After 24 hours, the glutathione content was doubled by vinclozolin, but was not affected by iprodione. No effect on glutathione S-transferase activity or reactive oxygen species formation could be observed. Cytochrome P450-dependent ethoxyresorufin-O-deethylase and pentoxyresorufin-O-depentylase activities were moderately activated by iprodione and strongly activated by vinclozolin. A glutathione-related cytochrome P450-dependent metabolic attack of vinclozolin and iprodione could be responsible for their cytotoxicity in Fa32 cells. Further research is needed to fully elucidate these (or other) mechanisms.

  20. Detection of Methicillin Resistant Staphylococcus aureus and Determination of Minimum Inhibitory Concentration of Vancomycin for Staphylococcus aureus Isolated from Pus/Wound Swab Samples of the Patients Attending a Tertiary Care Hospital in Kathmandu, Nepal

    Directory of Open Access Journals (Sweden)

    Raghabendra Adhikari

    2017-01-01

    Full Text Available The present study was conducted to evaluate the performance of cefoxitin disc diffusion method and oxacillin broth microdilution method for detection of methicillin resistant S. aureus (MRSA, taking presence of mecA gene as reference. In addition, inducible clindamycin resistance and beta-lactamase production were studied and minimum inhibitory concentration (MIC of vancomycin for S. aureus isolates was determined. A total of 711 nonrepeated pus/wound swab samples from different anatomic locations were included in the study. The Staphylococcus aureus was identified on the basis of colony morphology, Gram’s stain, and biochemical tests. A total of 110 (15.47% S. aureus isolates were recovered, of which 39 (35.50% isolates were identified as MRSA by cefoxitin disc diffusion method. By oxacillin broth microdilution method, 31.82% of the Staphylococcus aureus isolates were found to be MRSA. However, mecA gene was present in only 29.1% of the isolates. Further, beta-lactamase production was observed in 71.82% of the isolates, while inducible clindamycin resistance was found in 10% of S. aureus isolates. The MIC value of vancomycin for S. aureus ranged from 0.016 μg/mL to 1 μg/mL. On the basis of the absolute sensitivity (100%, both phenotypic methods could be employed for routine diagnosis of MRSA in clinical microbiology laboratory; however cefoxitin disc diffusion could be preferred over MIC method considering time and labour factor.

  1. Disruption of quercetin metabolism by fungicide affects energy production in honey bees (Apis mellifera).

    Science.gov (United States)

    Mao, Wenfu; Schuler, Mary A; Berenbaum, May R

    2017-03-07

    Cytochrome P450 monooxygenases (P450) in the honey bee, Apis mellifera , detoxify phytochemicals in honey and pollen. The flavonol quercetin is found ubiquitously and abundantly in pollen and frequently at lower concentrations in honey. Worker jelly consumed during the first 3 d of larval development typically contains flavonols at very low levels, however. RNA-Seq analysis of gene expression in neonates reared for three days on diets with and without quercetin revealed that, in addition to up-regulating multiple detoxifying P450 genes, quercetin is a negative transcriptional regulator of mitochondrion-related nuclear genes and genes encoding subunits of complexes I, III, IV, and V in the oxidative phosphorylation pathway. Thus, a consequence of inefficient metabolism of this phytochemical may be compromised energy production. Several P450s metabolize quercetin in adult workers. Docking in silico of 121 pesticide contaminants of American hives into the active pocket of CYP9Q1, a broadly substrate-specific P450 with high quercetin-metabolizing activity, identified six triazole fungicides, all fungal P450 inhibitors, that dock in the catalytic site. In adults fed combinations of quercetin and the triazole myclobutanil, the expression of five of six mitochondrion-related nuclear genes was down-regulated. Midgut metabolism assays verified that adult bees consuming quercetin with myclobutanil metabolized less quercetin and produced less thoracic ATP, the energy source for flight muscles. Although fungicides lack acute toxicity, they may influence bee health by interfering with quercetin detoxification, thereby compromising mitochondrial regeneration and ATP production. Thus, agricultural use of triazole fungicides may put bees at risk of being unable to extract sufficient energy from their natural food.

  2. Potential mechanisms underlying response to effects of the fungicide pyrimethanil from gene expression profiling in Saccharomyces cerevisiae.

    Science.gov (United States)

    Gil, Fátima N; Becker, Jörg D; Viegas, Cristina A

    2014-06-11

    Pyrimethanil is a fungicide mostly applied in vineyards. When misused, residue levels detected in grape must or in the environment may be of concern. The present work aimed to analyze mechanisms underlying response to deleterious effects of pyrimethanil in the eukaryotic model Saccharomyces cerevisiae. Pyrimethanil concentration-dependent effects at phenotypic (inhibition of growth) and transcriptomic levels were examined. For transcriptional profiling, analysis focused on two sublethal exposure conditions that inhibited yeast growth by 20% or 50% compared with control cells not exposed to the fungicide. Gene expression modifications increased with the magnitude of growth inhibition, in numbers and fold-change of differentially expressed genes and in diversity of over-represented functional categories. These included mostly biosynthesis of arginine and sulfur amino acids metabolism, as well as energy conservation, antioxidant response, and multidrug transport. Several pyrimethanil-responsive genes encoded proteins sharing significant homology with proteins from phytopathogenic fungi and ecologically relevant higher eukaryotes.

  3. Profitability of fungicide use decisions among cocoa farmers in south ...

    African Journals Online (AJOL)

    A decision theoretic approach and regression method were used to analyze the data collected. The results indicated that (i) expected crop loss should be taken into account when deciding on the amount of fungicides to apply in the study area and (ii) the use rate recommended by CRIN could not be used in all situations – it ...

  4. Fungicide sensitivity in the wild rice pathogen Bipolaris oryzae

    Science.gov (United States)

    In recent years the occurrence of fungal brown spot, caused by Bipolaris oryzae has increased in cultivated wild rice (Zizania palustris) paddies in spite of the use of fungicides. To implement an efficient integrated disease management system, we are exploring whether field isolates have developed ...

  5. Oral Toxicity of Agro-Fungicides: Tilt (Propiconazole), Bayleton ...

    African Journals Online (AJOL)

    Methods: Twelve Nubian goats were used in these experiments; they were grouped into three groups (and one control group) and dosed orally with two fungicides [Propiconazole (100mg/kg/day), Triadimefon (100mg/kg/day)] and their mixture (50:50 mg/kg/day). Animals were closely observed for clinical signs and behavior ...

  6. Influence of fungicides on gas exchange of pecan foliage

    Science.gov (United States)

    There are several fungicide chemistries used for disease control on pecan (Carya illinoinensis), but there is little or no knowledge of subtle short- or long-term side-effects of these chemistries on host physiological processes, including photosynthesis (Pn). This study quantifies the impact of se...

  7. Systemic fungicidal activity of 1,4-oxathiin derivatives.

    Science.gov (United States)

    Schmeling, B V; Kulka, M

    1966-04-29

    Treatment of pinto bean and barley seed with 1,4-oxathiin derivatives gave disease control by systemic fungicidal action of such pathogenic fungi as Uromyces phaseoli and Ustilago nuda. The two chemicals, D735 and F461, were highly specific and selective against the pathogens without injury of the hosts.

  8. field tolerance of selected varieties to and fungicide efficacy against ...

    African Journals Online (AJOL)

    ACSS

    and median temperatures of 28°C (Osiru et al.,. 2007), it has the potential ... this study was to evaluate a wide range of sweet ... following each fungicide application to reduce wash-off. ..... specific mode of action (Avenot and Michailides,. 2007 ...

  9. Effect of benzimidazole fungicides and calcium chloride on ...

    African Journals Online (AJOL)

    SERVER

    2007-06-04

    Jun 4, 2007 ... Botrytis cinerea (Besri and Diatta, 1985; Hmouni et al.,. 1996). It is very likely that the repetitive uses of these systemic fungicides and their persistence during long periods of conservation (Ben Arie, 1975; Prusky, 1985) have led to considerable selective pressure on both species. Moreover, the single site ...

  10. Biological activity of triazole fungicides towards Botrytis cinerea

    NARCIS (Netherlands)

    Stehmann, C.

    1995-01-01

    Botrytis cinerea Pers. ex Fr., the causal agent of grey mould, is one of the most ubiquitous plant pathogens. The fungus is of high economic importance in various major crops and during transport and storage of agricultural products. Protectant fungicides such as

  11. Suppression of hop looper (Lepidoptera: Noctuidae) by the fungicide pyraclostrobin.

    Science.gov (United States)

    Woods, J L; Gent, D H

    2014-04-01

    The hop looper, Hypena humuli Harris, is a reemergent pest of hop that often requires treatment to mitigate crop damage. In 4 yr of field trials, plots treated with fungicides were observed to sustain less hop looper defoliation compared with nontreated plots. Further investigation revealed that abundance of hop looper and associated defoliation were reduced when the fungicide pyraclostrobin was applied in late July to early August. Two other fungicides possessing active ingredients in the same chemical family (quinone outside inhibitor) did not reduce abundance of hop looper or its defoliation. Pyraclostrobin is efficacious against powdery mildew diseases, and the application timing evaluated in these studies corresponds with a period of juvenile susceptibility of hop cones to the disease. Use of fungicides containing pyraclostrobin at this time may have the ancillary benefit of reducing hop looper damage, potentially obviating the need for broad-spectrum insecticides later in the season. Follow-up studies are warranted to determine whether pyraclostrobin may inhibit other lepidopteran species.

  12. Minimum Wages and Poverty

    OpenAIRE

    Fields, Gary S.; Kanbur, Ravi

    2005-01-01

    Textbook analysis tells us that in a competitive labor market, the introduction of a minimum wage above the competitive equilibrium wage will cause unemployment. This paper makes two contributions to the basic theory of the minimum wage. First, we analyze the effects of a higher minimum wage in terms of poverty rather than in terms of unemployment. Second, we extend the standard textbook model to allow for incomesharing between the employed and the unemployed. We find that there are situation...

  13. In-Vitro Evaluation of Fungicides and Fungicide Combinations Against Fusarium Root-Rot Fungal Pathogens of French Beans(Phaseolus Vulgaris L. c v. Monel

    International Nuclear Information System (INIS)

    Wagichunge, A.G.R; Owino, P.O; Waudo, S.W; Seif, A.A

    1999-01-01

    Laboratories studies were undertaken to evaluate In-vitro efficacy of captan, thiram, pyrazophos, triforine and metalaxyl + mancozeb fungicides against Fusarium solani (Mart.) Appel and Wollenw fsp. phaseoli (Burk) Synder and Hansen Fusarium oxysporum Schlecht fsp. phaseoli kend and Synder root-rot fungal pathogens of French beans. Five fungicides and four combinations were tested for their antifungal activity. Fungicides treatments significantly (P=0.05) inhibited mycelial growth and spore germination. Fungicides suppressed the growth of F. oxysporum fsp. Phaseoli more than that of F. solani fsp. phaseoli. All fungicides except metalaxyl + mancozeb failed to suppress sporulation of the two fungi In-vitro. In the case of thiram the sporulation capacity of F. oxysporum fsp. phaseoli 3.43 times higher than in the control. Although, no fungicides treatment was seen to inhibitor of all the three measures of fungitoxicity, the ranking of the best three fungicide treatments would be, thiram 50 + captan so > triforine > metalaxyl + mancozeb. The relatively higher inhibitory effect of fungicides on the growth of F. oxysporum Ssp. Phaseoli than that of F. solani fsp. Phaseoli suggested that F. oxysporum Esp. Phaseoli was more sensible to fungicide treatments. Such differences may reflect inherent variations in accessibility of the active toxicants within the fungal systems. The ability attributed to the low growth rate, N depletion temperature and oxygen

  14. Synthesis and Fungicidal Activity of β-Carboline Alkaloids and Their Derivatives

    Directory of Open Access Journals (Sweden)

    Zhibin Li

    2015-07-01

    Full Text Available A series of β-Carboline derivatives were designed, synthesized, and evaluated for their fungicidal activities in this study. Several derivatives electively exhibited fungicidal activities against some fungi. Especially, compound F5 exhibited higher fungicidal activity against Rhizoctonia solani (53.35% than commercial antiviral agent validamycin (36.4%; compound F16 exhibited high fungicidal activity against Oospora citriaurantii ex Persoon (43.28%. Some of the alkaloids and their derivatives (compounds F4 and F25 exhibited broad-spectrum fungicidal activity. Specifically, compound F4 exhibited excellent high broad-spectrum fungicidal activity in vitro, and the curative and protection activities against P. litchi in vivo reached 92.59% and 59.26%, respectively. The new derivative, F4, with optimized physicochemical properties, obviously exhibited higher activities both in vitro and in vivo; therefore, F4 may be used as a new lead structure for the development of fungicidal drugs.

  15. Determination of the Minimum Inhibitory Concentration of the Barberry Extract and the Dried Residue of Red Grape and Their Effects on the Growth Inhibition of Sausage Bacteria by Using Response Surface Methodology (RSM

    Directory of Open Access Journals (Sweden)

    Fatemeh Riazi

    2015-09-01

    Full Text Available Background and Objectives: With regard to the hazards of nitrite, application of natural preservatives in order to reduce the microbial load of meat and meat products is increasing. Owing to their anti-bacterial properties, red barberry and the dried residue of red grape could be suitable replacers for nitrite. Materials and Methods: Agar dilution method was employed in order to determine the minimum inhibitory concentration (MIC of the barberry extract and the dried residue of red grape. The anti-microbial effects of the barberry extract (0-600 mg/kg, the dried residue of red grape (0-2% and nitrite (30-90 mg/kg were investigated on the total viable counts of Clostridium perfringens, as well as on the psychrophilic bacteria after 30 days of storage at 4°C. Finally, the effects of the three independent variables in the optimal sample were examined on the growth of the inoculated C. perfringens. Results: The MIC of the barberry extract and the dried residue of red grape on Staphylococcus aureus was 3 and 6 (mg/ml, respectively. In the case of Escherichia coli, it was 4 and 7 (mg/ml, respectively. The barberry extract and nitrite reduced the growth of the living aerobic bacteria significantly. The spores of the inoculated C. perfringens had no growth in the optimum sample during storage. Conclusions: The barberry extract and the dried residue of red grape as natural preservatives, could partially substitute for nitrite in order to reduce the microbial load of sausage.

  16. The fungicide triadimefon affects beer flavor and composition by influencing Saccharomyces cerevisiae metabolism

    Science.gov (United States)

    Kong, Zhiqiang; Li, Minmin; An, Jingjing; Chen, Jieying; Bao, Yuming; Francis, Frédéric; Dai, Xiaofeng

    2016-09-01

    Despite the fact that beer is produced on a large scale, the effects of pesticide residues on beer have been rarely investigated. In this study, we used micro-brewing settings to determine the effect of triadimefon on the growth of Saccharomyces cerevisiae and beer flavor. The yeast growth in medium was significantly inhibited (45%) at concentrations higher than 5 mg L-1, reaching 80% and 100% inhibition at 10 mg L-1 and 50 mg L-1, respectively. There were significant differences in sensory quality between beer samples fermented with and without triadimefon based on data obtained with an electronic tongue and nose. Such an effect was most likely underlain by changes in yeast fermentation activity, including decreased utilization of maltotriose and most amino acids, reduced production of isobutyl and isoamyl alcohols, and increased ethyl acetate content in the fungicide treated samples. Furthermore, yeast metabolic profiling by phenotype microarray and UPLC/TOF-MS showed that triadimefon caused significant changes in the metabolism of glutathione, phenylalanine and sphingolipids, and in sterol biosynthesis. Thus, triadimefon negatively affects beer sensory qualities by influencing the metabolic activity of S. cerevisiae during fermentation, emphasizing the necessity of stricter control over fungicide residues in brewing by the food industry.

  17. Time-dependent sorption of two novel fungicides in soils within a regulatory framework.

    Science.gov (United States)

    Gulkowska, Anna; Buerge, Ignaz J; Poiger, Thomas; Kasteel, Roy

    2016-12-01

    Convincing experimental evidence suggests increased sorption of pesticides on soil over time, which, so far, has not been considered in the regulatory assessment of leaching to groundwater. Recently, Beulke and van Beinum (2012) proposed a guidance on how to conduct, analyse and use time-dependent sorption studies in pesticide registration. The applicability of the recommended experimental set-up and fitting procedure was examined for two fungicides, penflufen and fluxapyroxad, in four soils during a 170 day incubation experiment. The apparent distribution coefficient increased by a factor of 2.5-4.5 for penflufen and by a factor of 2.5-2.8 for fluxapyroxad. The recommended two-site, one-rate sorption model adequately described measurements of total mass and liquid phase concentration in the calcium chloride suspension and the calculated apparent distribution coefficient, passing all prescribed quality criteria for model fit and parameter reliability. The guidance is technically mature regarding the experimental set-up and parameterisation of the sorption model for the two moderately mobile and relatively persistent fungicides under investigation. These parameters can be used for transport modelling in soil, thereby recognising the existence of the experimentally observed, but in the regulatory leaching assessment of pesticides not yet routinely considered phenomenon of time-dependent sorption. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  18. GIBBERELLINS, FUNGICIDES AND STORAGE EFFECTS ON THE GERMINATION OF Genipa americana L. (RUBIACEAE SEEDS

    Directory of Open Access Journals (Sweden)

    Fábio de Almeida Vieira

    2006-06-01

    Full Text Available The aim of this paper was to verify the effect of different doses of gibberellic acid (GA3 (0, 250, 500, 750 and 1000 µg.L-1, of fungicides of the groups chemical benzimidazol (0, 25, 50 and 100 g.L-1 and ditiocarbamato (0, 1,25, 2,50 and 5,00 g.L-1 on seed germination. Viability of those seeds was evaluated through germination tests at 0, 15, 30 and 60 days. The experiment was carried out in greenhouse. The experimental design was fully randomized one, with five replicates per treatment. The traits evaluated were emergence and index of emergence speed. The treatment with GA3 didn't provide significant so much differences among the germination rates as well as for the emergence speed. It was verified that the use of the fungicides in smaller concentrations (25 g.L-1 of benzimidazol and 1,25 g.L-1 of ditiocarbamato promoted a better germination speed. The seeds of G. americana possess viability period relatively short, with germination absence 60 days period of storage, and it could be associated to the humidity tenors presented by the seeds in this period.

  19. Identification of QoI fungicide-resistant genotypes of the wheat pathogen Zymoseptoria tritici in Algeria

    Directory of Open Access Journals (Sweden)

    Nora ALLIOUI

    2016-05-01

    Full Text Available Septoria tritici blotch caused by Zymoseptoria tritici is currently one of the most damaging diseases on bread and durum wheat crops worldwide. A total of 120 monoconidial isolates of this fungus were sampled in 2012 from five distinct geographical locations of Algeria (Guelma, Annaba, Constantine, Skikda and Oran and assessed for resistance to Quinone outside Inhibitors (QoI, a widely used class of fungicides for the control of fungal diseases of wheat. Resistance was screened using a mismatch PCR assay that identified the G143A mitochondrial cytochrome b substitution associated with QoI resistance. The isolates were QoI-sensitive, since all possessed the G143 wild-type allele, except for three isolates (two from Guelma and one from Annaba, which had fungicide resistance and possessed the A143 resistant allele. QoI resistance was confirmed phenotypically using a microplate bioassay in which the resistant isolates displayed high levels of half-maximal inhibitory azoxystrobin concentrations (IC50s when compared to sensitive reference isolates. Genetic fingerprinting of all isolates with microsatellite markers revealed that the three resistant isolates were distinct haplotypes, and were are not genetically distinguishable from the sensitive isolates. This study highlights QoI-resistant genotypes of Z. tritici in Algeria for the first time, and proposes a management strategy for QoI fungicide application to prevent further spread of resistance across the country or to other areas of Northern Africa.

  20. Assessing the potential effects of fungicides on nontarget gut fungi (trichomycetes) and their associated larval black fly hosts

    Science.gov (United States)

    Wilson, Emma R.; Smalling, Kelly L.; Reilly, Timothy J.; Gray, Elmer; Bond, Laura; Steele, Lance; Kandel, Prasanna; Chamberlin, Alison; Gause, Justin; Reynolds, Nicole; Robertson, Ian; Novak, Stephen; Feris, Kevin; White, Merlin M.

    2014-01-01

    Fungicides are moderately hydrophobic and have been detected in water and sediment, particularly in agricultural watersheds, but typically are not included in routine water quality monitoring efforts. This is despite their widespread use and frequent application to combat fungal pathogens. Although the efficacy of these compounds on fungal pathogens is well documented, little is known about their effects on nontarget fungi. This pilot study, a field survey in southwestern Idaho from April to December 2010 on four streams with varying pesticide inputs (two agricultural and two reference sites), was conducted to assess nontarget impact of fungicides on gut fungi, or trichomycetes. Tissues of larval black flies (Diptera: Simuliidae), hosts of gut fungi, were analyzed for pesticide accumulation. Fungicides were detected in hosts from streams within agricultural watersheds but were not detected in hosts from reference streams. Gut fungi from agricultural sites exhibited decreased percent infestation, density and sporulation within the gut, and black fly tissues had elevated pesticide concentrations. Differences observed between the sites demonstrate a potential effect on this symbiotic system. Future research is needed to parse out the details of the complex biotic and abiotic relationships; however, these preliminary results indicate that impacts to nontarget organisms could have far-reaching consequences within aquatic ecosystems.

  1. Degradation of the fungicide carbendazim in aqueous solutions with UV/TiO2 process: Optimization, kinetics and toxicity studies

    International Nuclear Information System (INIS)

    Saien, J.; Khezrianjoo, S.

    2008-01-01

    An attempt was made to investigate the potential of UV-photocatalytic process in the presence of TiO 2 particles for the degradation of carbendazim (C 9 H 9 N 3 O 2 ), a fungicide with a high worldwide consumption but considered as a 'priority hazard substance' by the Water Framework Directive of the European Commission (WFDEC). A circulating upflow photo-reactor was employed and the influence of catalyst concentration, pH and temperature were investigated. The results showed that degradation of this fungicide can be conducted in the both processes of only UV-irradiation and UV/TiO 2 ; however, the later provides much better results. Accordingly, a degradation of more than 90% of fungicide was achieved by applying the optimal operational conditions of 70 mg L -1 of catalyst, natural pH of 6.73 and ambient temperature of 25 deg. C after 75 min irradiation. Under these mild conditions, the initial rate of degradation can be described well by the Langmuir-Hinshelwood kinetic model. Toxicological assessments on the obtained samples were also performed by measurement of the mycelium growth inhibition of Fusarium oxysporum fungus on PDA medium. The results indicate that the kinetics of degradation and toxicity are in reasonably good agreement mainly after 45 min of irradiation; confirming the effectiveness of photocatalytic process

  2. Changes in Sensitivity Levels of Botrytis spp. Population Isolated from Lily to Fungicides and Control under Field Condition

    Directory of Open Access Journals (Sweden)

    Soosang Hahm

    2013-03-01

    Full Text Available Forty eight isolates of Botrytis elliptica and 23 isolates of B. cinerea from several locations in Korea were tested for resistance to fungicides used in the farmer's fields. Isolation frequency of B. elliptica having EC50 (effective concentration of 50% value 500−1000 μg/ml to benomyl and mancozeb appeared highly, suggesting that the two fungicides are not effective in controlling leaf blight of lily in the field. The isolates were tested for resistance to fungicides procymidone and iprodione which were most commonly used in the farmer's fields. The rates of EC50 value 5−50 μg/ml to procymidome and iprodione were 93.7% and 100%, respectively, and those of 0−0.1 μg/ml to diethofencarb+carbendazim and fludioxonil were 98.0% and 93.8%, respectively. In the rain-protected cultivation, control of leaf blight of lily was the most effective when iprodine, diethofencarb+ carbendazim, and fludioxonil were sprayed alternately four times during the growing season.

  3. Determination of neonicotinoid insecticides and strobilurin fungicides in particle phase atmospheric samples by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Raina-Fulton, Renata

    2015-06-03

    A liquid chromatography-tandem mass spectrometry method has been developed for the determination of neonicotinoids and strobilurin fungicides in the particle phase fraction of atmosphere samples. Filter samples were extracted with pressurized solvent extraction, followed by a cleanup step with solid phase extraction. Method detection limits for the seven neonicotinoid insecticides and six strobilurin fungicides were in the range of 1.0-4.0 pg/m(3). Samples were collected from June to September 2013 at two locations (Osoyoos and Oliver) in the southern Okanagan Valley Agricultural Region of British Columbia, where these insecticides and fungicides are recommended for use on tree fruit crops (apples, pears, cherries, peaches, apricots) and vineyards. This work represents the first detection of acetamiprid, imidacloprid, clothianidin, kresoxim-methyl, pyraclostrobin, and trifloxystrobin in particle phase atmospheric samples collected in the Okanagan Valley in Canada. The highest particle phase atmospheric concentrations were observed for imidacloprid, pyraclostrobin, and trifloxystrobin at 360.0, 655.6, and 1908.2 pg/m(3), respectively.

  4. Changes in metabolic activities of Fusarium oxysporum f. fabae and Rhizoctonia solani in response to Dithan A-40 fungicide.

    Science.gov (United States)

    Zaki, M M; Mahmoud, S A; Hamed, A S; Sahab, A F

    1979-01-01

    The effect of different concentrations of Dithan A-40 fungicide on the metabolic activities of the wilt fungus Fusarium oxysporum f. fabae and the root rot agent Rhizoctonia solani was studied. All toxicant concentrations reduced energy generation, total phosphorus and nitrogen content of both fungi. In addition, the toxicant caused a shift in free amino acids pool. As a result of these changes, the mycelium dry weight of both fungi was greatly reduced. R. solani was more sensitive to the toxic effect of Dithan A-40 than F. oxysporum.

  5. Photodegradation of multiclass fungicides in the aquatic environment and determination by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Celeiro, Maria; Facorro, Rocio; Dagnac, Thierry; Vilar, Vítor J P; Llompart, Maria

    2017-08-01

    The photodegradation behaviour for nine widespread fungicides (benalaxyl, cyprodinil, dimethomorph, fenhexamide, iprovalicarb, kresoxim-methyl, metalaxyl, myclobutanil and tebuconazole) was evaluated in different types of water. Two different systems, direct UV photolysis and UVC/H 2 O 2 advanced oxidation process (AOP), were applied for the photodegradation tests. For the monitoring of the target compound degradation, a method based on direct injection liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. Several fungicide photodegradation by-products were tentatively identified by high-resolution mass spectrometry (HRMS) as well. For the photolysis studies, the efficiency of different types of radiation, UVC (λ = 254 nm) and UVA (λ = 365 nm), was compared. UVC photolysis provided the highest removal with a complete degradation for fenhexamide and kresoxim-methyl, and percentages between 48 and 78% for the other compounds, excluding iprovalicarb and myclobutanil with removals <35%, after 30 min of irradiation. Besides, the photodegradation tests were performed with different initial concentrations of fungicides, and the efficiency of two photoreactor systems was compared. In all cases, the kinetics followed pseudo-first order, and the half-life times could also be calculated. The addition of H 2 O 2 under UVC light allowed an improvement of the reaction kinetics, especially for the most recalcitrant fungicides, obtaining in all cases removals higher than 82% in less than 6 min. Finally, in order to evaluate the suitability of the proposed systems, both UVC photolysis and UVC/H 2 O 2 system were tested in different real water matrices (wastewater, tap water, swimming pool water and river water), showing that the UVC/H 2 O 2 system had the highest removal efficiency in less than 6 min, for all water samples.

  6. Minimum critical mass systems

    International Nuclear Information System (INIS)

    Dam, H. van; Leege, P.F.A. de

    1987-01-01

    An analysis is presented of thermal systems with minimum critical mass, based on the use of materials with optimum neutron moderating and reflecting properties. The optimum fissile material distributions in the systems are obtained by calculations with standard computer codes, extended with a routine for flat fuel importance search. It is shown that in the minimum critical mass configuration a considerable part of the fuel is positioned in the reflector region. For 239 Pu a minimum critical mass of 87 g is found, which is the lowest value reported hitherto. (author)

  7. Sensitivity of Phakopsora pachyrhizi (soybean rust) isolates to fungicides and the reduction of fungal sporulation based on fungicide and timing of application

    Science.gov (United States)

    Soybean rust is a damaging foliar fungal disease of soybean in many soybean-growing areas throughout the world. Strategies to manage soybean rust include the use of foliar fungicides. Fungicides types, the rate of product application, and the number and timing of applications are critical components...

  8. Minimum entropy production principle

    Czech Academy of Sciences Publication Activity Database

    Maes, C.; Netočný, Karel

    2013-01-01

    Roč. 8, č. 7 (2013), s. 9664-9677 ISSN 1941-6016 Institutional support: RVO:68378271 Keywords : MINEP Subject RIV: BE - Theoretical Physics http://www.scholarpedia.org/article/Minimum_entropy_production_principle

  9. Peptides of the Constant Region of Antibodies Display Fungicidal Activity

    Science.gov (United States)

    Polonelli, Luciano; Ciociola, Tecla; Magliani, Walter; Zanello, Pier Paolo; D'Adda, Tiziana; Galati, Serena; De Bernardis, Flavia; Arancia, Silvia; Gabrielli, Elena; Pericolini, Eva; Vecchiarelli, Anna; Arruda, Denise C.; Pinto, Marcia R.; Travassos, Luiz R.; Pertinhez, Thelma A.; Spisni, Alberto; Conti, Stefania

    2012-01-01

    Synthetic peptides with sequences identical to fragments of the constant region of different classes (IgG, IgM, IgA) of antibodies (Fc-peptides) exerted a fungicidal activity in vitro against pathogenic yeasts, such as Candida albicans, Candida glabrata, Cryptococcus neoformans, and Malassezia furfur, including caspofungin and triazole resistant strains. Alanine-substituted derivatives of fungicidal Fc-peptides, tested to evaluate the critical role of each residue, displayed unaltered, increased or decreased candidacidal activity in vitro. An Fc-peptide, included in all human IgGs, displayed a therapeutic effect against experimental mucosal and systemic candidiasis in mouse models. It is intriguing to hypothesize that some Fc-peptides may influence the antifungal immune response and constitute the basis for devising new antifungal agents. PMID:22470523

  10. Peptides of the constant region of antibodies display fungicidal activity.

    Directory of Open Access Journals (Sweden)

    Luciano Polonelli

    Full Text Available Synthetic peptides with sequences identical to fragments of the constant region of different classes (IgG, IgM, IgA of antibodies (Fc-peptides exerted a fungicidal activity in vitro against pathogenic yeasts, such as Candida albicans, Candida glabrata, Cryptococcus neoformans, and Malassezia furfur, including caspofungin and triazole resistant strains. Alanine-substituted derivatives of fungicidal Fc-peptides, tested to evaluate the critical role of each residue, displayed unaltered, increased or decreased candidacidal activity in vitro. An Fc-peptide, included in all human IgGs, displayed a therapeutic effect against experimental mucosal and systemic candidiasis in mouse models. It is intriguing to hypothesize that some Fc-peptides may influence the antifungal immune response and constitute the basis for devising new antifungal agents.

  11. Fungicide Efficacy in Peach Rusty Spot Control in Serbia

    Directory of Open Access Journals (Sweden)

    Nenad Dolovac

    2010-01-01

    Full Text Available Rusty Spot has long been known as a harmful peach disease in many parts of the world. During the past several years, rusty spot infection of the late-maturing peach cultivars (Summerset, Suncrest, Fayette and O’Henry caused significant yield losses in Serbia.Although the etiology of the disease is still unknown, there are numerous studies attempting to set a strategy for its control and recommend appropriate chemical and other peach protection methods. However, because of specific environmental conditions in Serbia, recommended protection method using repeated fungicide treatments, starting from petal fall, did not prove to be efficient and the rate of infection in some susceptible peach cultivars reached 100%. In 2003 and 2004 a field trial was conducted in order to test the efficacy of fungicides (a.i. kresoxim-methyl, flusilazole and sulfur for the efficient control of Rusty Spot epidemics. The trial was carried out under conditions of natural infection on the peach cv. Summerset at the locality of Bela Crkva, Serbia. In the ntreated control plots,high disease incidence was recorded with the percentage of affected fruit surface ranging from 33.5% in the first, up to the 35.4% in the second year of the trail. Among fungicides included in the trial, kresoxim-methyl proved to be the most efficient (90.25% in the first and 91.12% in the second year of the trial, flusilazole exhibited lower efficacy (87.28% and 80.61%, respectively while sulfur was the least efficient 82.33% and 80.30%, respectively. Determination of the most efficient fungicide for the peach rusty spot control in Serbia provides basic nformation for further investigations which will include optimization of treatment terms, as well as additional agro-technical control measures.

  12. Radioisotopes and fungicide research- present status and future prospects

    International Nuclear Information System (INIS)

    Chatrath, M.S.

    1996-01-01

    The developments in pesticides and radioisotopes fields were so near to each other that at a very early stage in this history, both became linked together and their usefulness was recognised for faster development. The purpose of this communication is to illustrate the present status these techniques in fungicide research by drawing suitable examples and also to bring out the directions in which future research will be going with the aid of these tools. 72 refs

  13. EFFICACY OF FUNGICIDES AGAINST CALONECTRIA PAUCIRAMOSA IN POT AZALEA.

    Science.gov (United States)

    Heungens, K; Pauwels, E

    2015-01-01

    Calonectria (formerly Cylindrocladium) infection of pot azalea (Rhododendron simsii Planch) is an important disease problem in which usually one or two of the four plants per pot show progressing leaf and especially stem lesions, leading to mortality of the respective plant and rendering the pot unmarketable. This may occur in a later stage of the growing season, leading to significant commercial losses. The main objective of this study was to test a range of fungicides for their efficacy against this pathogen. To test the fungicides, a bioassay was first developed in which mycelium and conidiospores of the pathogen were produced on Potato Dextrose Agar, blended in water, and dilutions of the resulting suspension inoculated at the base of 11-week-old cuttings three weeks after they had been trimmed. Disease progression was monitored up to 7 weeks post inoculation and a disease index on a scale of 0 to 3 was established. In the actual efficacy trial, the following fungicides (with corresponding active ingredient(s)) were tested as preventive treatments: Topsin M 70 WG (thiophanate-methyl), Sporgon (prochloraz), Signum (boscalid+pyraclostrobin), Switch (cyprodinyl+fludioxonil), Flint 50WG (trifloxystrobin), Ortiva Top (azoxystrobin+difenoconazole) and Fungaflor (imazalil). Disease expression started after about 2 weeks, increased approximately 1 index level, and leveled off 5 weeks after inoculation. The best control was observed with Sporgon, Ortiva Top and Signum. Switch produced intermediate effects and insufficient control was observed with Topsin, Flint and Fungaflor. These results explain why specific standard fungicide treatments, such as those with Topsin, fail to control the disease, while they can be effective against a different Calonectria species such as C. pseudonaviculata, the cause of boxwood blight.

  14. Radiotracer studies of fungicide residues in food plants

    International Nuclear Information System (INIS)

    1990-04-01

    Agricultural fungicides are chemicals used on seeds, crops and in soils throughout the growing season. Fungicide treatments may lead to various levels of chemical residues in food commodities. Primary emphasis has been placed on ethylenebisdithiocarbamates (EBDCs), an important group of agrofungicides used in preparations for spraying or dusting major crops such as apples, pears, broccoli, cabbages, egg plants, cauliflower, grapes, lettuce, peppers, celery, cucumbers and tomatoes. Treatments with EBDCs result in terminal residues containing ethylenthiourea (ETU). This is a toxicologically significant decomposition product which has attracted considerable attention in recent years due to indications of its potential goitrogenic and carcinogenic properties. In recognition of the need for a coordinated examination of ETU levels in food, particularly under tropical conditions, the program of radiotracer techniques as a tool for studying fungicide residue problems on food was initiated in 1984. In current studies, three EBDCs, maneb, zineb and mancozeb from different manufacturers in different countries were analysed. This report describes the model protocols (Annexes I, II and III) as they were set up for determination of residues in commodities and soil, using radiotracer and conventional chromatographic techniques . In the 16 papers presented in this report C 14 -labelled EBDCs are determined in plants, vegetables, and soils, before and after cooking, as a function of time and of other agricultural parameters. Refs, figs and tabs

  15. Antimicrobial multiple resistance index, minimum inhibitory concentrations, and extended-spectrum beta-lactamase producers of Proteus mirabilis and Proteus vulgaris strains isolated from domestic animals with various clinical manifestations of infection

    Directory of Open Access Journals (Sweden)

    Vanessa Zappa

    2017-05-01

    Full Text Available Proteus spp. are opportunistic multidrug resistant enterobacteria associated with diverse clinical diseases in domestic animals. However, Proteus infections in domestic animals are often misdiagnosed or considered contaminants in microbiological cultures rather than a primary agent of disease. Descriptions of Proteus infections in domestic animals are typically restricted to case reports, retrospective studies, or surveillance of other microorganisms. The present study investigated multiple antibiotic resistance indices, minimum inhibitory concentrations (MICs, and ESBL production in 73 strains of Proteus mirabilis (n = 69 and Proteus vulgaris (n = 4 isolated from domestic animals with various clinical manifestations. In dogs, the pathogen was most commonly associated with cystitis (48.21, enteritis (21.42%, otitis (14.29%, and conjunctivitis (3.57%. In bovines, the microorganism was predominant in cases of enteritis (22.22%, abscess (11.11%, otitis (11.11%, omphalitis (11.11%, and peritonitis (11.11%, and in organ fragments (11.11%. In equines (50.0% and cats (100.0%, diarrhea was the main clinical sign. In vitro standard disk diffusion assay showed that the most effective antimicrobials against the isolates were imipenem (98.63, norfloxacin (95.89, amikacin (95.89, levofloxacin (90.41, ceftriaxone (87.64, and florfenicol (87.67. In contrast, the isolates commonly showed resistance to novobiocin (95.89, azithromycin (57.53, and trimethropim/sulfamethoxazole (39.73. Among the 73 isolates, the efficacy of amoxicillin/clavulanic acid, gentamicin, ceftriaxone, and ciprofloxacin according to MICs was 87.67%, 86.30%, 84.93%, and 82.19%, respectively. The MIC50 values of amoxicillin/clavulanic acid, ceftriaxone, ciprofloxacin, and gentamicin were, respectively, 1.0, 0.004, 0.03, and 1.0 µg/mL. Thirty-three strains (45.21% showed a antimicrobial multiple resistance index of ? 0.3. Multidrug resistance profiles of isolates were observed most frequently

  16. Curative and eradicant action of fungicides to control Phakopsora pachyrhizi in soybean plants

    Directory of Open Access Journals (Sweden)

    Erlei Melo Reis

    Full Text Available ABSTRACT Experiments were carried out in a growth chamber and laboratory to quantify the curative and eradicant actions of fungicides in Asian soybean rust control. The experiments were conducted with the CD 214 RR cultivar, assessing the following fungicides, separately or in association, chlorothalonil, flutriafol, cyproconazole + trifloxystrobin, epoxiconazole + pyraclostrobin, cyproconazole + azoxystrobin, and cyproconazole + picoxystrobin. The fungicides were applied at four (curative and nine days after inoculation (eradicant treatment. Treatments were evaluated according to the density of lesions and uredia/cm2, and the eradicant treatment was assessed based on the necrosis of lesions/uredia and on uredospore viability. Except for the fungicide chlorothalonil, there was curative action of latent/virtual infections by the fungicides. Penetrant fungicides that are absorbed have curative and eradicant action to soybean rust.

  17. Energetic endpoints provide early indicators of life history effects in a freshwater gastropod exposed to the fungicide, pyraclostrobin

    International Nuclear Information System (INIS)

    Fidder, Bridgette N.; Reátegui-Zirena, Evelyn G.; Olson, Adric D.; Salice, Christopher J.

    2016-01-01

    Organismal energetics provide important insights into the effects of environmental toxicants. We aimed to determine the effects of pyraclostrobin on Lymnaea stagnalis by examining energy allocation patterns and life history traits. Juvenile snails exposed to pyraclostrobin decreased feeding rate and increased apparent avoidance behaviors at environmentally relevant concentrations. In adults, we found that sublethal concentrations of pyraclostrobin did not affect reproductive output, however, there were significant effects on developmental endpoints with longer time to hatch and decreased hatching success in pyraclostrobin-exposed egg masses. Further, there were apparent differences in developmental effects depending on whether mothers were also exposed to pyraclostrobin suggesting this chemical can exert intergenerational effects. Pyraclostrobin also affected protein and carbohydrate content of eggs in mothers that were exposed to pyraclostrobin. Significant effects on macronutrient content of eggs occurred at lower concentrations than effects on gross endpoints such as hatching success and time to hatch suggesting potential value for these endpoints as early indicators of ecologically relevant stress. These results provide important insight into the effects of a common fungicide on important endpoints for organismal energetics and life history. - Highlights: • We exposed a freshwater snail to relevant concentrations of pyraclostrobin. • We monitored energetic and life history endpoints. • Pyraclostrobin affected feeding, hatching success and egg macronutrient content. • Energetic-based endpoints may provide valuable insight to toxic effects. - The fungicide pyraclostrobin at environmentally relevant concentrations effects a range of life history and energetic endpoints in the freshwater snail, Lymnaea stagnalis.

  18. Fungicidal PMMA-Undecylenic Acid Composites

    Directory of Open Access Journals (Sweden)

    Milica Petrović

    2018-01-01

    Full Text Available Undecylenic acid (UA, known as antifungal agent, still cannot be used to efficiently modify commercial dental materials in such a way that this affects Candida. Actually, issues with Candida infections and fungal resistance compromise the use of Poly(methyl-methacrylate (PMMA as dental material. The challenge remains to turn PMMA into an antifugal material, which can ideally affect both sessile (attached and planktonic (free-floating Candida cells. We aimed to tackle this challenge by designing PMMA-UA composites with different UA concentrations (3–12%. We studied their physico-chemical properties, the antifungal effect on Candida and the cytotoxicity toward human cells. We found that UA changes the PMMA surface into a more hydrophilic one. Mainly, as-preparation composites with ≥6% UA reduced sessile Candida for >90%. After six days, the composites were still efficiently reducing the sessile Candida cells (for ~70% for composites with ≥6% UA. Similar results were recorded for planktonic Candida. Moreover, the inhibition zone increased along with the UA concentration. The antifungal effect of UA was also examined at the surface of an UA-loaded agar and the minimal inhibitory concentration (MIC90 was below the lowest-studied 0.0125% UA. Furthermore, the embedded filamentation test after 24 h and 48 h showed complete inhibition of the Candida growth at 0.4% UA.

  19. Fungicidal PMMA-Undecylenic Acid Composites

    Science.gov (United States)

    Petrović, Milica; Hofmann, Heinrich

    2018-01-01

    Undecylenic acid (UA), known as antifungal agent, still cannot be used to efficiently modify commercial dental materials in such a way that this affects Candida. Actually, issues with Candida infections and fungal resistance compromise the use of Poly(methyl-methacrylate) (PMMA) as dental material. The challenge remains to turn PMMA into an antifugal material, which can ideally affect both sessile (attached) and planktonic (free-floating) Candida cells. We aimed to tackle this challenge by designing PMMA-UA composites with different UA concentrations (3–12%). We studied their physico-chemical properties, the antifungal effect on Candida and the cytotoxicity toward human cells. We found that UA changes the PMMA surface into a more hydrophilic one. Mainly, as-preparation composites with ≥6% UA reduced sessile Candida for >90%. After six days, the composites were still efficiently reducing the sessile Candida cells (for ~70% for composites with ≥6% UA). Similar results were recorded for planktonic Candida. Moreover, the inhibition zone increased along with the UA concentration. The antifungal effect of UA was also examined at the surface of an UA-loaded agar and the minimal inhibitory concentration (MIC90) was below the lowest-studied 0.0125% UA. Furthermore, the embedded filamentation test after 24 h and 48 h showed complete inhibition of the Candida growth at 0.4% UA. PMID:29316713

  20. Fungicidal PMMA-Undecylenic Acid Composites.

    Science.gov (United States)

    Petrović, Milica; Bonvin, Debora; Hofmann, Heinrich; Mionić Ebersold, Marijana

    2018-01-08

    Undecylenic acid (UA), known as antifungal agent, still cannot be used to efficiently modify commercial dental materials in such a way that this affects Candida . Actually, issues with Candida infections and fungal resistance compromise the use of Poly(methyl-methacrylate) (PMMA) as dental material. The challenge remains to turn PMMA into an antifugal material, which can ideally affect both sessile (attached) and planktonic (free-floating) Candida cells. We aimed to tackle this challenge by designing PMMA-UA composites with different UA concentrations (3-12%). We studied their physico-chemical properties, the antifungal effect on Candida and the cytotoxicity toward human cells. We found that UA changes the PMMA surface into a more hydrophilic one. Mainly, as-preparation composites with ≥6% UA reduced sessile Candida for >90%. After six days, the composites were still efficiently reducing the sessile Candida cells (for ~70% for composites with ≥6% UA). Similar results were recorded for planktonic Candida . Moreover, the inhibition zone increased along with the UA concentration. The antifungal effect of UA was also examined at the surface of an UA-loaded agar and the minimal inhibitory concentration (MIC90) was below the lowest-studied 0.0125% UA. Furthermore, the embedded filamentation test after 24 h and 48 h showed complete inhibition of the Candida growth at 0.4% UA.

  1. Abundance, genetic diversity and sensitivity to demethylation inhibitor fungicides of Aspergillus fumigatus isolates from organic substrates with special emphasis on compost.

    Science.gov (United States)

    Santoro, Karin; Matić, Slavica; Gisi, Ulrich; Spadaro, Davide; Pugliese, Massimo; Gullino, Maria L

    2017-12-01

    Aspergillus fumigatus is a widespread fungus that colonizes dead organic substrates but it can also cause fatal human diseases. Aspergilloses are treated with demethylation inhibitor (DMI) fungicides; however, resistant isolates appeared recently in the medical and also environmental area. The present study aims at molecular characterizing and quantifying A. fumigatus in major environmental habitats and determining its sensitivity to medical and agricultural DMI fungicides. A. fumigatus was isolated only rarely from soil and meadow/forest organic matter but high concentrations (10 3 to 10 7  cfu/g) were detected in substrates subjected to elevated temperatures, such as compost and silage. High genetic diversity of A. fumigatus from compost was found based on SSR markers, distinguishing among fungal isolates even when coming from the same substrate sample, while subclustering was observed based on mutations in cyp51A gene. Several cyp51A amino acid substitutions were found in 15 isolates, although all isolates were fully sensitive to the tested DMI fungicides, with exception of one isolate in combination with one fungicide. This study suggests that the tested A. fumigatus isolates collected in Italy, Spain and Hungary from the fungus' major living habitats (compost) and commercial growing substrates are not potential carriers for DMI resistance in the environment. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  2. Effects of nitrous oxide on minimum alveolar concentration of desflurane in dogs Efeitos do óxido nitroso sobre a concentração alveolar mínima do desfluorano, em cães

    Directory of Open Access Journals (Sweden)

    C.T. Nishimori

    2007-02-01

    Full Text Available Effects of nitrous oxide (N2O on minimum alveolar concentration (MAC of desflurane were studied. For that purpose, 30 dogs were randomly allocated into two groups: desflurane group (GD and N2O and desflurane group (GDN. GD animals received propofol to intubation, and 11.5V% of desflurane diluted in 100% O2. After 30 minutes, they received electric stimulus and if the animal did not react to stimulus, desflurane concentration was reduced by 1.5V%. This protocol was repeated at each 15 minutes, and stimulus was interrupted when voluntary reaction was observed. GDN dogs were submitted to diluent flow 30% O2 and 70% N2O. Desflurane's MAC; heart (HR and respiratory (RR rates; systolic, diastolic and mean arterial pressures (SAP, DAP, and MAP, respectively; end tidal carbon dioxide (ETCO2; oxyhemoglobin saturation (SpO2 and body temperature (T were evaluated. In both groups increase in HR and ETCO2, and decrease in RR and T were associated with administration of the highest dose of desflurane. Blood pressures decreased 30 minutes after desflurane administration in GDN, and after this measurement the values increased. Reduction in desflurane's MAC was observed as well. It is concluded that N2O associated with desflurane reduced desflurane's MAC by 16% with increase in HR and respiratory depression.Estudaram-se os efeitos do óxido nitroso (N2O sobre a concentração alveolar mínima (CAM do desfluorano. Trinta cães foram distribuídos em dois grupos: desfluorano (GD e N2O e desfluorano (GDN. Os do GD receberam propofol (8,9±1,65mg/kg para intubação orotraqueal e após, 11,5V% de desfluorano em 100% de O2. Após 30 minutos, os animais receberam estímulo elétrico e não havendo reação do animal, reduziu-se a concentração em 1,5V%. Repetiu-se o protocolo a cada 15 minutos, cessando-se os estímulos quando observada reação voluntária. Os GDN foram submetidos ao mesmo protocolo, substituindo-se o fluxo diluente por 30% O2 e 70% N2O. Mensuraram

  3. Mutants of Venturia ineaqualis (Cook) Wint. apple scar resistant to fungicides

    International Nuclear Information System (INIS)

    Bedianashvili, Ts.V.; D'yakov, Yu.T.

    1987-01-01

    Mutants of apple scab resistant to zineb and bayleton fungicides have been obtained upon action of UV irradiation and nitrosome-thylurea. Using tetrade analysis, two zineb resistence genes have been found. The mutations are pleiotropic and lead to increase in resistance to other fungicides, decrease in growth rate on artificial media, increase in spore size, sporulation, and aggressiveness, decrease in competitiveness at in vitro growth. The resistance is supposed to be determined by decrease in membrane permeability for fungicides

  4. Phytotoxicity: An Overview of the Physiological Responses of Plants Exposed to Fungicides

    Directory of Open Access Journals (Sweden)

    Maria Celeste Dias

    2012-01-01

    Full Text Available In the last decades, the use of fungicides in agriculture for fungi diseases control has become crucial. Fungicide research has produced a diverse range of products with novel modes of action. However, the extensive use of these compounds in the agriculture system raises public concern because of the harmful potential of such substances in the environment and human health. Moreover, the phytotoxic effects of some fungicides are already recognized but little is known about the impact of these compounds on the photosynthetic apparatus. This paper presents a comprehensive overview of the literature considering different classes of fungicides and their effects on plant physiology, with particular emphasis on photosynthesis.

  5. Effects of selected herbicides and fungicides on growth, sporulation and conidial germination of entomopathogenic fungus Beauveria bassiana.

    Science.gov (United States)

    Celar, Franci A; Kos, Katarina

    2016-11-01

    The in vitro fungicidal effects of six commonly used fungicides, namely fluazinam, propineb, copper(II) hydroxide, metiram, chlorothalonil and mancozeb, and herbicides, namely isoxaflutole, fluazifop-P-butyl, flurochloridone, foramsulfuron, pendimethalin and prosulfocarb, on mycelial growth, sporulation and conidial germination of entomopathogenic fungus Beauveria bassiana (ATCC 74040) were investigated. Mycelial growth rates and sporulation at 15 and 25 °C were evaluated on PDA plates containing 100, 75, 50, 25, 12.5, 6.25 and 0% of the recommended application rate of each pesticide. The tested pesticides were classified in four scoring categories based on reduction in mycelial growth and sporulation. All pesticides, herbicides and fungicides tested had fungistatic effects of varying intensity, depending on their rate in the medium, on B. bassiana. The most inhibitory herbicides were flurochloridone and prosulfocarb, and fluazinam and copper(II) hydroxide were most inhibitory among the fungicides, while the least inhibitory were isoxaflutole and chlorothalonil. Sporulation and conidial germination of B. bassiana were significantly inhibited by all tested pesticides compared with the control treatment. Flurochloridone, foramsulfuron, prosulfocarb and copper(II) hydroxide inhibited sporulation entirely at 100% rate (99-100% inhibition), and the lowest inhibition was shown by fluazifop-P-butyl (22%) and metiram (33%). At 100% dosage, all herbicides in the test showed a high inhibitory effect on conidial germination. Conidial germination inhibition ranged from 82% with isoxaflutole to 100% with fluorochloridone, pendimethalin and prosulfocarb. At 200% dosage, inhibition rates even increased (96-100%). All 12 pesticides tested had a fungistatic effect on B. bassiana of varying intensity, depending on the pesticide and its concentration. B. bassiana is highly affected by some herbicides and fungicides even at very low rates. Flurochloridone, foramsulfuron

  6. Leaching and sorption of neonicotinoid insecticides and fungicides from seed coatings

    Science.gov (United States)

    Smalling, Kelly; Hladik, Michelle; Sanders, Corey; Kuivila, Kathryn

    2018-01-01

    Seed coatings are a treatment used on a variety of crops to improve production and offer protection against pests and fungal outbreaks. The leaching of the active ingredients associated with the seed coatings and the sorption to soil was evaluated under laboratory conditions using commercially available corn and soybean seeds to study the fate and transport of these pesticides under controlled conditions. The active ingredients (AI) included one neonicotinoid insecticide (thiamethoxam) and five fungicides (azoxystrobin, fludioxonil, metalaxyl, sedaxane thiabendazole). An aqueous leaching experiment was conducted with treated corn and soybean seeds. Leaching potential was a function of solubility and seed type. The leaching of fludioxonil, was dependent on seed type with a shorter time to equilibrium on the corn compared to the soybean seeds. Sorption experiments with the treated seeds and a solution of the AIs were conducted using three different soil types. Sorption behavior was a function of soil organic matter as well as seed type. For most AIs, a negative relationship was observed between the aqueous concentration and the log Koc. Sorption to all soils tested was limited for the hydrophilic pesticides thiamethoxam and metalaxyl. However, partitioning for the more hydrophobic fungicides was dependent on both seed type and soil properties. The mobility of fludioxonil in the sorption experiment varied by seed type indicating that the adjuvants associated with the seed coating could potentially play a role in the environmental fate of fludioxonil. This is the first study to assess, under laboratory conditions, the fate of pesticides associated with seed coatings using commercially available treated seeds. This information can be used to understand how alterations in agricultural practices (e.g., increasing use of seed treatments) can impact the exposure (concentration and duration) and potential effects of these chemicals to aquatic and terrestrial organisms.

  7. Conazole fungicides inhibit Leydig cell testosterone secretion and androgen receptor activation in vitro

    Directory of Open Access Journals (Sweden)

    Maarke J.E. Roelofs

    2014-01-01

    Full Text Available Conazole fungicides are widely used in agriculture despite their suspected endocrine disrupting properties. In this study, the potential (anti-androgenic effects of ten conazoles were assessed and mutually compared with existing data. Effects of cyproconazole (CYPRO, fluconazole (FLUC, flusilazole (FLUS, hexaconazole (HEXA, myconazole (MYC, penconazole (PEN, prochloraz (PRO, tebuconazole (TEBU, triadimefon (TRIA, and triticonazole (TRIT were examined using murine Leydig (MA-10 cells and human T47D-ARE cells stably transfected with an androgen responsive element and a firefly luciferase reporter gene. Six conazoles caused a decrease in basal testosterone (T secretion by MA-10 cells varying from 61% up to 12% compared to vehicle-treated control. T secretion was concentration-dependently inhibited after exposure of MA-10 cells to several concentrations of FLUS (IC50 = 12.4 μM or TEBU (IC50 = 2.4 μM in combination with LH. The expression of steroidogenic and cholesterol biosynthesis genes was not changed by conazole exposure. Also, there were no changes in reactive oxygen species (ROS formation that could explain the altered T secretion after exposure to conazoles. Nine conazoles decreased T-induced AR activation (IC50s ranging from 10.7 to 71.5 μM and effect potencies (REPs were calculated relative to the known AR antagonist flutamide (FLUT. FLUC had no effect on AR activation by T. FLUS was the most potent (REP = 3.61 and MYC the least potent (REP = 0.03 AR antagonist. All other conazoles had a comparable REP from 0.12 to 0.38. Our results show distinct in vitro anti-androgenic effects of several conazole fungicides arising from two mechanisms: inhibition of T secretion and AR antagonism, suggesting potential testicular toxic effects. These effects warrant further mechanistic investigation and clearly show the need for accurate exposure data in order to perform proper (human risk assessment of this class of compounds.

  8. Effects of agricultural fungicides on microorganisms associated with floral nectar: susceptibility assays and field experiments.

    Science.gov (United States)

    Bartlewicz, Jacek; Pozo, María I; Honnay, Olivier; Lievens, Bart; Jacquemyn, Hans

    2016-10-01

    Pesticides have become an inseparable element of agricultural intensification. While the direct impact of pesticides on non-target organisms, such as pollinators, has recently received much attention, less consideration has been given to the microorganisms that are associated with them. Specialist yeasts and bacteria are known to commonly inhabit floral nectar and change its chemical characteristics in numerous ways, possibly influencing pollinator attraction. In this study, we investigated the in vitro susceptibility of nectar yeasts Metschnikowia gruessi, Metschnikowia reukaufii, and Candida bombi to six widely used agricultural fungicides (prothioconazole, tebuconazole, azoxystrobin, fenamidone, boscalid, and fluopyram). Next, a commercial antifungal mixture containing tebuconazole and trifloxystrobin was applied to natural populations of the plant Linaria vulgaris and the occurrence, abundance, and diversity of nectar-inhabiting yeasts and bacteria was compared between treated and untreated plants. The results showed that prothioconazole and tebuconazole were highly toxic to nectar yeasts, inhibiting their growth at concentrations varying between 0.06 and 0.5 mg/L. Azoxystrobin, fenamidone, boscalid, and fluopyram on the other hand exhibited considerably lower toxicity, inhibiting yeast growth at concentrations between 1 and 32 mg/L or in many cases not inhibiting microbial growth at all. The application of the antifungal mixture in natural plant populations resulted in a significant decrease in the occurrence and abundance of yeasts in individual flowers, but this did not translate into noticeable changes in bacterial incidence and abundance. Yeast and bacterial species richness and distribution did not also differ between treated and untreated plants. We conclude that the application of fungicides may have negative effects on the abundance of nectar yeasts in floral nectar. The consequences of these effects on plant pollination processes in agricultural

  9. Low-airflow drying of fungicide-treated shelled corn

    International Nuclear Information System (INIS)

    Peterson, W.H.; Benson, P.W.

    1993-02-01

    Approved fungicides inhibit mold growth in shelled corn and allow for longer, natural-air drying. The longer drying periods permit lower than-normal airflows and smaller power units, thus reducing electrical demands on utilities in corn-producing states. Researchers placed approximately 67 m 3 (1900 bu) of one variety of shelled corn at approximately 24% moisture in each of five equally sized storage bins. They partitioned each bin vertically and filled one half of each bin with fungicide-treated corn and one half with untreated corn. Each of four bins used a different airflow. A fifth bin used the lowest of the four airflows but was equipped to capture and use solar energy. All corn dried rapidly with resulting good quality. The percentage of damaged kernels was significantly higher for untreated than for treated corn. The energy required for the lowest airflow system was approximately one half of that required for the higher, more traditional airflows. Because of lower-than-normal airflows, the electrical demand on the utility is approximately one fourth as great as that imposed when the higher, more traditional natural-air systems are used. The 1991 corn growing and drying seasons were unusual in central Illinois, the site of the study. Both harvest and drying occurred several weeks ahead of schedule. Additional work is needed to verify that findings hold true during more-normal Midwest corn growing and drying seasons; the investigators predict that they will. It should be noted that the fungicide used in this study has not yet been approved for widespread use in drying corn

  10. Conversion of the fungicide, ziram in rice plants

    International Nuclear Information System (INIS)

    Kumarasamy, R.; Raghu, K.

    1976-01-01

    Zinc dimethyldithiocarbamate (ziram) is a toliar fungicide used for the control of the blast disease of rice caused by Pyricularia oryzae, and is also used for the control of the plant diseases in crops like groundnut, cotton, etc. Since there is lack of data on the conversion products of this fungicide. This investigation was carried out. The results of the author's recent studies with 35 S-labelled ziram in rice seedlings were reported. The 35 S-Labelled ziram (specific activity 1.5 m Ci/m mole) was sprayed on the rice seedlings of 25 days old. At different intervals of time, the seedlings were removed, washed thoroughly, cut into pieces, and extracted with 80% ethanol. By the method described in ''K. Raghu et al., Origin and fate of chemical residents in food, agriculture and fisheries, I.A.E.A., Vienna, 1975, pp. 137-148,'' the segments corresponding to the standards of dimethyl dithio carbamate-alanine (DDCA), DDC-glucoside (DDCG), thiazolidine-2-thione-4-carbamic acid (TTCA), unidentified divolent fungicide (X), and ziram were cut out and the radioactivity was counted in cocktail D scintillation fluid using an LS-100 Beckmann liquid scintillation counter. It is indeed interesting to note that ziram is converted in plant tissues into dimethyldithiocarbamate derivatives like DDCG, DDCA, TTCA and X within 24 hr after spraying. The amounts of these derivatives varied in the course of sampling up to 8 days after spraying. Further studies are needed as to the quantitative nature of these products, but the present report clearly demonstrates the formation of these conversion products in the rice leaves treated with ziram. (Kobatake, H.)

  11. Bioengineered silver nanoparticles using Curvularia pallescens and its fungicidal activity against Cladosporium fulvum

    Directory of Open Access Journals (Sweden)

    Abdallah M. Elgorban

    2017-11-01

    Full Text Available Microorganisms based biosynthesis of nanomaterials has triggered significant attention, due to their great potential as vast source of the production of biocompatible nanoparticles (NPs. Such biosynthesized functional nanomaterials can be used for various biomedical applications. The present study investigates the green synthesis of silver nanoparticles (Ag NPs using the fungus Curvularia pallescens (C. pallescens which is isolated from cereals. The C. pallescens cell filtrate was used for the reduction of AgNO3 to Ag NPs. To the best of our knowledge C. pallescens is utilized first time for the preparation of Ag NPs. Several alkaloids and proteins present in the phytopathogenic fungus C. pallescens were mainly responsible for the formation of highly crystalline Ag NPs. The as-synthesized Ag NPs were characterized by using UV–Visible spectroscopy, X-ray diffraction and transmission electron microscopy (TEM. The TEM micrographs have revealed that spherical shaped Ag NPs with polydisperse in size were obtained. These results have clearly suggested that the biomolecules secreted by C. pallescens are mainly responsible for the formation and stabilization of nanoparticles. Furthermore, the antifungal activity of the as-prepared Ag NPs was tested against Cladosporium fulvum, which is the major cause of a serious plant disease, known as tomato leaf mold. The synthesized Ag NPs displayed excellent fungicidal activity against the tested fungal pathogen. The extreme zone of reduction occurred at 50 μL, whereas, an increase in the reduction activity is observed with increasing the concentration of Ag NPs. These encouraging results can be further exploited by employing the as synthesized Ag NPs against various pathogenic fungi in order to ascertain their spectrum of fungicidal activity.

  12. An evaluation of some fungicides in the management of fruit and leaf ...

    African Journals Online (AJOL)

    Four fungicide treatments viz Ben late (Benomyl), Cupravit (Copper oxychloride), Dithane M45 (Mancozeb), and. Ben late alternated with Dithane M45 were applied to control P!laeoramularia angolensi~ In a block of the variety. "Valencia" in the citrus orchard at Kiige, Uganda. No fungicide was applied to the control.

  13. Effectiveness of Fungicide on Soybean Rust in the Southeastern United States: A Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Mary Delaney

    2018-05-01

    Full Text Available Soybean rust (SBR, caused by the fungus Phakopsora pachyrhizi Sydow, has been of concern to soybean (Glycine max Merrill growers in the southern United States since its introduction in 2004. As this fungus develops, pustules become numerous on the underside of leaves, which then turn yellow and drop prematurely, resulting in fewer pods, and poorly developed seeds. Our objective was to evaluate the efficacy of fungicide use in controlling SBR by conducting a meta-analysis of 61 published and unpublished trials across the southern United States from 2004 to 2014. We analyzed fungicide efficacy based on factors such as specific classes of fungicide, active ingredients, number of fungicide applications, target growth stage upon initial application, level of disease pressure, and year of the study. Fungicides significantly increased yield and 100-seed weight and decreased the severity of SBR. The means of SBR severity, yield, and 100-seed weight in fungicide-treated plants were 9% (95% confidence interval: 2%, 21%, 128% (121%, 135%, and 121% (116%, 128%, respectively, of those calculated in the control plants. By using meta-analysis to analyze fungicide efficacy across multiple field trials, we were able to determine that one application of a strobilurin fungicide when plants were either beginning pod development (R3 or developing seeds (R5 was the most cost-effective approach to controlling SBR and increasing 100-seed weight.

  14. Activity of two strobilurin fungicides against three species of decay fungi in agar plate tests

    Science.gov (United States)

    Juliet D. Tang; Tina Ciaramitaro; Maria Tomaso-Peterson; Susan V. Diehl

    2017-01-01

    The objective of this study was to examine the toxicity of strobilurin fungicides against wood decay fungi in order to assess their potential to act as a co-biocide for copper-based wood protection. Two strobilurin fungicides, Heritage (50% azoxystrobin active ingredient) and Insignia (20% pyraclostrobin active ingredients), and copper sulfate pentahydrate were tested...

  15. Effectiveness of fungicides in protecting Douglas-fir shoots from infection by Phytophthora ramorum

    Science.gov (United States)

    G.A. Chastagner; E.M. Hansen; K.L. Riley; W. Sutton

    2006-01-01

    The effectiveness of 20 systemic and contact fungicides in protecting Douglas-fir seedlings from infection by Phytophthora ramorum was determined. Some systemic products were applied about a week prior to bud break, while most treatments were applied just after bud break. In addition to the fungicides, two surfactants were included in the post-bud...

  16. Effects of azole fungicides on the function of sex and thyroid hormones

    DEFF Research Database (Denmark)

    Kjærstad, Mia Birkhøj; Andersen, Helle Raun; Taxvig, Camilla

    Azole-fungicides are frequently used in Denmark. Epoxiconazole, propiconazole, and tebuconazole had endocrine disrupting properties in cell based assays. In rats, epoxiconazole and tebuconazole increased gestational length, maternal progesterone level, and masculinized female-offspring. Besides, ......, tebuconazole caused feminization of male-offspring. Similar effects were previously demonstrated for prochloraz. The results indicate that azole-fungicides in general have endocrine disrupting properties....

  17. Evaluating Headline fungicide on alfalfa production and sensitivity of pathogens to pyraclostrobin

    Science.gov (United States)

    Headline fungicide was recently registered for management of foliar diseases on alfalfa. The effect of disease control on yield, forage quality, and potential return on investment for fungicide application was determined for field experiments conducted at five locations in 2012, three in Wisconsin a...

  18. Rising above the Minimum Wage.

    Science.gov (United States)

    Even, William; Macpherson, David

    An in-depth analysis was made of how quickly most people move up the wage scale from minimum wage, what factors influence their progress, and how minimum wage increases affect wage growth above the minimum. Very few workers remain at the minimum wage over the long run, according to this study of data drawn from the 1977-78 May Current Population…

  19. Suspension Array for Multiplex Detection of Eight Fungicide-Resistance Related Alleles in Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Xin Zhang

    2016-09-01

    Full Text Available A simple and high-throughput assay to detect fungicide resistance is required for large-scale monitoring of the emergence of resistant strains of Botrytis cinerea. Using suspension array technology performed on a Bio-Plex 200 System, we developed a single-tube allele-specific primer extension (ASPE assay that can simultaneously detect eight alleles in one reaction. These eight alleles include E198 and 198A of the β-Tubulin gene (BenA, H272 and 272Y of the Succinate dehydrogenase iron–sulfur subunit gene (SdhB, I365 and 365S of the putative osmosensor histidine kinase gene (BcOS1, and F412 and 412S of the 3-ketoreductase gene (erg27. This assay was first established and optimized with eight plasmid templates containing the DNA sequence variants BenA-E198, BenA-198A, SdhB-H272, SdhB-272Y, BcOS1-I365, BcOS1-365S, erg27-F412, and erg27-412S. Results indicated that none of the probes showed cross-reactivity with one another. The minimum limit of detection for these genotypes was one copy per test. Four mutant plasmids were mixed with 10 ng/μL wild-type genomic DNA in different ratios. Detection sensitivity of mutant loci was 0.45% for BenA-E198A, BcOS1-I365S, and erg27-F412S, and was 4.5% for SdhB-H272Y. A minimum quantity of 0.1 ng of genomic DNA was necessary to obtain reliable results. This is the first reported assay that can simultaneously detect mutations in BenA, SdhB, BcOS1, and erg27.

  20. Suspension Array for Multiplex Detection of Eight Fungicide-Resistance Related Alleles in Botrytis cinerea.

    Science.gov (United States)

    Zhang, Xin; Xie, Fei; Lv, Baobei; Zhao, Pengxiang; Ma, Xuemei

    2016-01-01

    A simple and high-throughput assay to detect fungicide resistance is required for large-scale monitoring of the emergence of resistant strains of Botrytis cinerea . Using suspension array technology performed on a Bio-Plex 200 System, we developed a single-tube allele-specific primer extension assay that can simultaneously detect eight alleles in one reaction. These eight alleles include E198 and 198A of the β-Tubulin gene ( BenA ), H272 and 272Y of the Succinate dehydrogenase iron-sulfur subunit gene ( SdhB) , I365 and 365S of the putative osmosensor histidine kinase gene ( BcOS1 ), and F412 and 412S of the 3-ketoreductase gene ( erg27 ). This assay was first established and optimized with eight plasmid templates containing the DNA sequence variants BenA- E198, BenA- 198A, SdhB- H272, SdhB- 272Y, BcOS1- I365, BcOS1- 365S, erg27 -F412, and erg27 -412S. Results indicated that none of the probes showed cross-reactivity with one another. The minimum limit of detection for these genotypes was one copy per test. Four mutant plasmids were mixed with 10 ng/μL wild-type genomic DNA in different ratios. Detection sensitivity of mutant loci was 0.45% for BenA- E198A, BcOS1- I365S, and erg27 -F412S, and was 4.5% for SdhB- H272Y. A minimum quantity of 0.1 ng of genomic DNA was necessary to obtain reliable results. This is the first reported assay that can simultaneously detect mutations in BenA , SdhB , BcOS1 , and erg27 .

  1. Sustained release of fungicide metalaxyl by mesoporous silica nanospheres

    Energy Technology Data Exchange (ETDEWEB)

    Wanyika, Harrison, E-mail: hwanyika@gmail.com [Jomo Kenyatta University of Agriculture and Technology, Department of Chemistry (Kenya)

    2013-08-15

    The use of nanomaterials for the controlled delivery of pesticides is nascent technology that has the potential to increase the efficiency of food production and decrease pollution. In this work, the prospect of mesoporous silica nanoparticles (MSN) for storage and controlled release of metalaxyl fungicide has been investigated. Mesoporous silica nanospheres with average particle diameters of 162 nm and average pore sizes of 3.2 nm were prepared by a sol-gel process. Metalaxyl molecules were loaded into MSN pores from an aqueous solution by a rotary evaporation method. The loaded amount of metalaxyl as evaluated by thermogravimetric analysis was about 14 wt%. Release of the fungicide entrapped in the MSN matrix revealed sustained release behavior. About 76 % of the free metalaxyl was released in soil within a period of 30 days while only 11.5 and 47 % of the metalaxyl contained in the MSN carrier was released in soil and water, respectively, within the same period. The study showed that MSN can be used to successfully store metalaxyl molecules in its mesoporous framework and significantly delay their release in soil.

  2. Design, Synthesis and Fungicidal Activities of Some Novel Pyrazole Derivatives

    Directory of Open Access Journals (Sweden)

    Xue-Ru Liu

    2014-09-01

    Full Text Available In order to discover new compounds with good fungicidal activities, 32 pyrazole derivatives were designed and synthesized. The structures of the target compounds were confirmed by 1H-NMR, 13C-NMR, and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS, and their fungicidal activities against Botrytis cinerea, Rhizoctonia solani Kuhn, Valsa mali Miyabe et Yamada, Thanatephorus cucumeris (Frank Donk, Fusarium oxysporum (S-chl f.sp. cucumerinum Owen, and Fusarium graminearum Schw were tested. The bioassay results indicated that most of the derivatives exhibited considerable antifungal activities, especially compound 26 containing a p-trifluoromethyl- phenyl moiety showed the highest activity, with EC50 values of 2.432, 2.182, 1.787, 1.638, 6.986, and 6.043 μg/mL against B. cinerea, R. solani, V. mali, T. cucumeris, F. oxysporum, and F. graminearum, respectively. Moreover, the activities of compounds such as compounds 27–32 were enhanced by introducing isothiocyanate and carboxamide moieties to the 5-position of the pyrazole ring.

  3. Botrytis cinerea Control and the Problem of Fungicide Resistance

    Directory of Open Access Journals (Sweden)

    Brankica Tanović

    2011-01-01

    Full Text Available Botrytis cinerea, the causal agent of grey mould, greatly affects fruit, grapevine, vegetable and ornamental crops production. It is a common causal agent of diseases in plants grown in protected areas, as well as fruit decay during storage and transport. The fungusinvades almost all parts of the plant in all developmental stages, and the symptoms are usually described as grey mould, grey mildew, brown rot and seedling blight. The paper reviews the current knowledge on control possibilities of this necrotrophic pathogen. Theattention is particularly paid to the mode of action of novel fungicides and to the problem of resistance. It is pointed out that by limiting the number of treatments in the growing season, avoiding the use of only one fungicide with a high risk for resistance development,appropriate application rate and timing, using mixtures of pesticides with different modes of action, as well as by alternative use of pesticides from different resistance groups, a longterm preservation of pesticide efficacy is provided.

  4. Selective effects of two systemic fungicides on soil fungi.

    Science.gov (United States)

    Abdel-Fattah, H M; Abdel-Kader, M I; Hamida, S

    1982-08-20

    BAS 317 00F was not toxic to the total count of fungi after 2 days but was regularly significantly toxic at the three doses after 5, 20 and 40 days and toxic at the low and the high doses after 80 days. In the agar medium, it was toxic to the counts of total fungi. Aspergillus, A. terreus, Rhizopus oryzae and Mucor racemosus at the high dose. Only the mycelial growth of Trichoderma viride which was significantly inhibited by the three doses when this fungicide was added to the liquid medium. Polyram-Combi induced two effects on the total population of soil fungi. One inhibitory and this was demonstrated almost regularly after 2, 10 and 40 days and the other stimulatory after 80 days of treatment with the low and the high doses. In the agar medium, this fungicide was very toxic to total fungi and to almost all fungal genera and species at the three doses. Several fungi could survive the high dose. In liquid medium, the test fungi showed variable degree of sensitivity and the most sensitive was Gliocladium roseum which was completely eradicated by the three doses.

  5. Sustained release of fungicide metalaxyl by mesoporous silica nanospheres

    International Nuclear Information System (INIS)

    Wanyika, Harrison

    2013-01-01

    The use of nanomaterials for the controlled delivery of pesticides is nascent technology that has the potential to increase the efficiency of food production and decrease pollution. In this work, the prospect of mesoporous silica nanoparticles (MSN) for storage and controlled release of metalaxyl fungicide has been investigated. Mesoporous silica nanospheres with average particle diameters of 162 nm and average pore sizes of 3.2 nm were prepared by a sol–gel process. Metalaxyl molecules were loaded into MSN pores from an aqueous solution by a rotary evaporation method. The loaded amount of metalaxyl as evaluated by thermogravimetric analysis was about 14 wt%. Release of the fungicide entrapped in the MSN matrix revealed sustained release behavior. About 76 % of the free metalaxyl was released in soil within a period of 30 days while only 11.5 and 47 % of the metalaxyl contained in the MSN carrier was released in soil and water, respectively, within the same period. The study showed that MSN can be used to successfully store metalaxyl molecules in its mesoporous framework and significantly delay their release in soil

  6. Dipping Strawberry Plants in Fungicides before Planting to Control Anthracnose

    Directory of Open Access Journals (Sweden)

    Myeong Hyeon Nam

    2014-03-01

    Full Text Available Anthracnose crown rot (ACR, caused by Colletotrichum fructicola, is a serious disease of strawberry in Korea. The primary inoculums of ACR were symptomless strawberry plants, plant debris, and other host plants. To effectively control anthracnose in symptomless transplanted strawberries, it is necessary to use diseasefree plants, detect the disease early, and apply a fungicide. Therefore, in 2010 and 2011, we evaluated the efficacy of pre-plant fungicide dips by using strawberry transplants infected by C. fructicola for the control of anthracnose. Dipping plants in prochloraz-Mn for 10 min before planting was most effective for controlling anthracnose in symptomless strawberry plants and resulted in more than 76% control efficacy. Azoxystrobin showed a control efficacy of over 40%, but plants treated with pyraclostrobin, mancozeb and iminoctadine tris showed high disease severity. The control efficacy of the dip treatment with prochloraz-Mn did not differ with temperature and time. Treatment with prochloraz-Mn for more than an hour caused growth suppression in strawberry plants. Therefore, the development of anthracnose can be effectively reduced by dipping strawberry plants for 10 min in prochloraz-Mn before planting.

  7. Assessment of spent mushroom substrate as sorbent of fungicides: influence of sorbent and sorbate properties.

    Science.gov (United States)

    Marín-Benito, Jesús M; Rodríguez-Cruz, M Sonia; Andrades, M Soledad; Sánchez-Martín, María J

    2012-01-01

    The capacity of spent mushroom substrate (SMS) as a sorbent of fungicides was evaluated for its possible use in regulating pesticide mobility in the environment. The sorption studies involved four different SMS types in terms of nature and treatment and eight fungicides selected as representative compounds from different chemical groups. Nonlinear sorption isotherms were observed for all SMS-fungicide combinations. The highest sorption was obtained by composted SMS from Agaricus bisporus cultivation. A significant negative and positive correlation was obtained between the K(OC) sorption constants and the polarity index values of sorbents and the K(OW) of fungicides, respectively. The statistic revealed that more than 77% of the variability in the K(OW) could be explained considering these properties jointly. The other properties of both the sorbent (total carbon, dissolved organic carbon, or pH) and the sorbate (water solubility) were nonsignificant. The hysteresis values for cyprodinil (log K(OW)= 4) were for all the sorbents much higher (>3) than for other fungicides. This was consistent with the remaining sorption after desorption considered as an indicator of the sorption efficiency of SMS for fungicides. Changes in the absorption bands of fungicides sorbed by SMS observed by FTIR permitted establishing the interaction mechanism of fungicides with SMS. The findings of this work provide evidence for the potential capacity of SMS as a sorbent of fungicides and the low desorption observed especially for some fungicides, although they suggest that more stabilized or humified organic substrates should be produced to enhance their efficiency in environmental applications. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  8. Effect of a fungicide and spray adjuvant on queen-rearing success in honey bees (Hymenoptera: Apidae).

    Science.gov (United States)

    Johnson, Reed M; Percel, Eric G

    2013-10-01

    Commercial producers of honey bee queens (Apis mellifera L.) have reported unexplained loss of immature queens during the larval or pupal stage. Many affected queen-rearing operations are situated among the almond orchards of California and report these losses in weeks after almond trees bloom. Almond flowers are a rich foraging resource for bees, but are often treated with fungicides, insecticides, and spray adjuvants during bloom. Anecdotal reports by queen producers associate problems in queen development with application of the fungicide Pristine (boscalid and pyraclostrobin) and spray adjuvants that are tank-mixed with it. To test the effect of these compounds on queen development, a new bioassay was developed in which queens are reared in closed swarm boxes for 4 d, until capping, with nurse bees fed exclusively on artificially contaminated pollen. Pollen was treated with four concentrations of formulated Pristine (0.4, 4, 40, and 400 ppm), a spray adjuvant (Break-Thru, 200 ppm), the combination of Pristine and spray adjuvant (400:200 ppm), the insect growth regulator insecticide diflubenzuron (100 ppm) as a positive control, or water as negative control. Chemical analysis revealed that low concentrations of pyraclostrobin (50 ppb), but no boscalid, were detectable in royal jelly secreted by nurse bees feeding on treated pollen. No significant difference in queen development or survival was observed between any of the experimental treatments and the negative control. Only diflubenzuron, the positive control, caused a substantial reduction in survival of immature queens.

  9. Two azole fungicides (carcinogenic triadimefon and non-carcinogenic myclobutanil) exhibit different hepatic cytochrome P450 activities in medaka fish

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chun-Hung [Department of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan (China); Chou, Pei-Hsin [Department of Environmental Engineering, National Cheng-Kung University, Tainan, Taiwan (China); Chen, Pei-Jen, E-mail: chenpj@ntu.edu.tw [Department of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan (China)

    2014-07-30

    Highlights: • We assess ecotoxicological impact of azole fungicides in the aquatic environment. • Carcinogenic and non-carcinogenic azoles show different CYP activities in medaka. • We compare azole-induced CYP expression and carcinogenesis between fish and rodents. • Liver CYP-enzyme induction is a key event in conazole-induced tumorigenesis. • We suggest toxicity evaluation methods for azole fungicides using medaka fish. - Abstract: Conazoles are a class of imidazole- or triazole-containing drugs commonly used as fungicides in agriculture and medicine. The broad application of azole drugs has led to the contamination of surface aquifers receiving the effluent of municipal or hospital wastewater or agricultural runoff. Several triazoles are rodent carcinogens; azole pollution is a concern to environmental safety and human health. However, the carcinogenic mechanisms associated with cytochrome P450 enzymes (CYPs) of conazoles remain unclear. We exposed adult medaka fish (Oryzias latipes) to continuous aqueous solutions of carcinogenic triadimefon and non-carcinogenic myclobutanil for 7 to 20 days at sub-lethal or environmentally relevant concentrations and assessed hepatic CYP activity and gene expression associated with CYP-mediated toxicity. Both triadimefon and myclobutanil induced hepatic CYP3A activity, but only triadimefon enhanced CYP1A activity. The gene expression of cyp3a38, cyp3a40, pregnane x receptor (pxr), cyp26b, retinoid acid receptor γ1 (rarγ1) and p53 was higher with triadimefon than myclobutanil. As well, yeast-based reporter gene assay revealed that 4 tested conazoles were weak agonists of aryl hydrocarbon receptor (AhR). We reveal differential CYP gene expression with carcinogenic and non-carcinogenic conazoles in a lower vertebrate, medaka fish. Liver CYP-enzyme induction may be a key event in conazole-induced tumorigenesis. This information is essential to evaluate the potential threat of conazoles to human health and fish

  10. Two azole fungicides (carcinogenic triadimefon and non-carcinogenic myclobutanil) exhibit different hepatic cytochrome P450 activities in medaka fish

    International Nuclear Information System (INIS)

    Lin, Chun-Hung; Chou, Pei-Hsin; Chen, Pei-Jen

    2014-01-01

    Highlights: • We assess ecotoxicological impact of azole fungicides in the aquatic environment. • Carcinogenic and non-carcinogenic azoles show different CYP activities in medaka. • We compare azole-induced CYP expression and carcinogenesis between fish and rodents. • Liver CYP-enzyme induction is a key event in conazole-induced tumorigenesis. • We suggest toxicity evaluation methods for azole fungicides using medaka fish. - Abstract: Conazoles are a class of imidazole- or triazole-containing drugs commonly used as fungicides in agriculture and medicine. The broad application of azole drugs has led to the contamination of surface aquifers receiving the effluent of municipal or hospital wastewater or agricultural runoff. Several triazoles are rodent carcinogens; azole pollution is a concern to environmental safety and human health. However, the carcinogenic mechanisms associated with cytochrome P450 enzymes (CYPs) of conazoles remain unclear. We exposed adult medaka fish (Oryzias latipes) to continuous aqueous solutions of carcinogenic triadimefon and non-carcinogenic myclobutanil for 7 to 20 days at sub-lethal or environmentally relevant concentrations and assessed hepatic CYP activity and gene expression associated with CYP-mediated toxicity. Both triadimefon and myclobutanil induced hepatic CYP3A activity, but only triadimefon enhanced CYP1A activity. The gene expression of cyp3a38, cyp3a40, pregnane x receptor (pxr), cyp26b, retinoid acid receptor γ1 (rarγ1) and p53 was higher with triadimefon than myclobutanil. As well, yeast-based reporter gene assay revealed that 4 tested conazoles were weak agonists of aryl hydrocarbon receptor (AhR). We reveal differential CYP gene expression with carcinogenic and non-carcinogenic conazoles in a lower vertebrate, medaka fish. Liver CYP-enzyme induction may be a key event in conazole-induced tumorigenesis. This information is essential to evaluate the potential threat of conazoles to human health and fish

  11. Minimum Error Entropy Classification

    CERN Document Server

    Marques de Sá, Joaquim P; Santos, Jorge M F; Alexandre, Luís A

    2013-01-01

    This book explains the minimum error entropy (MEE) concept applied to data classification machines. Theoretical results on the inner workings of the MEE concept, in its application to solving a variety of classification problems, are presented in the wider realm of risk functionals. Researchers and practitioners also find in the book a detailed presentation of practical data classifiers using MEE. These include multi‐layer perceptrons, recurrent neural networks, complexvalued neural networks, modular neural networks, and decision trees. A clustering algorithm using a MEE‐like concept is also presented. Examples, tests, evaluation experiments and comparison with similar machines using classic approaches, complement the descriptions.

  12. Implementation of bio-fungicides and seed treatment in organic rice cv. KDML 105 farming.

    Science.gov (United States)

    Thobunluepop, Pitipong

    2009-08-15

    This study was aimed to evaluate the several chemical compounds of relatively composite structure with antifungal activity from Thai local medical plants. The antifungal activity of Stemona curtisii HK. f., Stemona tuberose L., Acorus calamus L., Eugenia caryophyllus, Memmea siamensis Kost. and an eugenol active compound were studied in vitro. Four pathogenic seed borne fungi, Alternaria solani, Colletotrichum sp., Fusarium moniliforme and Rhizoctonia solani were used as target organisms. The agar overlay technique and spore inhibition techniques were applied for the determination of their essential oil and active compound antifungal activity at various concentration; 0.10, 0.25, 0.50 and 1.00% (v/v) and untreated as control (0% v/v). Eugenol active compound showed the strongest antifungal activity on all species of tested fungal species. On the other hand, the antifungal activity of those bio-fungicides was lined up into a series from strong to low, as follows: Eugenia caryophyllus > Acorus calamus Linn. > Stemona tuberosa L. > Stemona curtisii Hk.f, while Mammea siamensis Kost. could not control any fungal species. Moreover, after eugenol application, lysis of spore and inhibition of mycelium growth were detected. Microscopic analysis exhibited complete lysis of spores after 24 h at a concentration of 1.00% v/v. Moreover, at the same concentration and 96 h incubation the mycelia growth was completely inhibited.

  13. Do Minimum Wages Fight Poverty?

    OpenAIRE

    David Neumark; William Wascher

    1997-01-01

    The primary goal of a national minimum wage floor is to raise the incomes of poor or near-poor families with members in the work force. However, estimates of employment effects of minimum wages tell us little about whether minimum wages are can achieve this goal; even if the disemployment effects of minimum wages are modest, minimum wage increases could result in net income losses for poor families. We present evidence on the effects of minimum wages on family incomes from matched March CPS s...

  14. Spread of Botrytis cinerea Strains with Multiple Fungicide Resistance in German Horticulture.

    Science.gov (United States)

    Rupp, Sabrina; Weber, Roland W S; Rieger, Daniel; Detzel, Peter; Hahn, Matthias

    2016-01-01

    Botrytis cinerea is a major plant pathogen, causing gray mold rot in a variety of cultures. Repeated fungicide applications are common but have resulted in the development of fungal populations with resistance to one or more fungicides. In this study, we have monitored fungicide resistance frequencies and the occurrence of multiple resistance in Botrytis isolates from raspberries, strawberries, grapes, stone fruits and ornamental flowers in Germany in 2010 to 2015. High frequencies of resistance to all classes of botryticides was common in all cultures, and isolates with multiple fungicide resistance represented a major part of the populations. A monitoring in a raspberry field over six seasons revealed a continuous increase in resistance frequencies and the emergence of multiresistant Botrytis strains. In a cherry orchard and a vineyard, evidence of the immigration of multiresistant strains from the outside was obtained. Inoculation experiments with fungicide-treated leaves in the laboratory and with strawberry plants cultivated in the greenhouse or outdoors revealed a nearly complete loss of fungicide efficacy against multiresistant strains. B. cinerea field strains carrying multiple resistance mutations against all classes of site-specific fungicides were found to show similar fitness as sensitive field strains under laboratory conditions, based on their vegetative growth, reproduction, stress resistance, virulence and competitiveness in mixed infection experiments. Our data indicate an alarming increase in the occurrence of multiresistance in B. cinerea populations from different cultures, which presents a major threat to the chemical control of gray mold.

  15. Consequences of co-applying insecticides and fungicides for managing Thrips tabaci (Thysanoptera: Thripidae) on onion.

    Science.gov (United States)

    Nault, Brian A; Hsu, Cynthia L; Hoepting, Christine A

    2013-07-01

    Insecticides and fungicides are commonly co-applied in a tank mix to protect onions from onion thrips, Thrips tabaci Lindeman, and foliar pathogens. Co-applications reduce production costs, but past research shows that an insecticide's performance can be reduced when co-applied with a fungicide. An evaluation was made of the effects of co-applying spinetoram, abamectin and spirotetramat with commonly used fungicides, with and without the addition of a penetrating surfactant, on onion thrips control in onion fields. Co-applications of insecticides with chlorothalonil fungicides reduced thrips control by 25-48% compared with control levels provided by the insecticides alone in three of five trials. Inclusion of a penetrating surfactant at recommended rates with the insecticide and chlorothalonil fungicide did not consistently overcome this problem. Co-applications of insecticides with other fungicides did not interfere with thrips control. Co-applications of pesticides targeting multiple organisms should be examined closely to ensure that control of each organism is not compromised. To manage onion thrips in onion most effectively, insecticides should be applied with a penetrating surfactant, and should be applied separately from chlorothalonil fungicides. © 2012 Society of Chemical Industry.

  16. Effects of Fungicides, Time of Application, and Application Method on Control of Sclerotinia Blight in Peanut

    Directory of Open Access Journals (Sweden)

    Jason E. Woodward

    2015-01-01

    Full Text Available Field studies were conducted from 2007 to 2010 to evaluate the response of peanut cultivars to different fungicides, application timings, and methods. Overall, fungicides reduced Sclerotinia blight incidence and increased pod yields when applied to susceptible and partially resistant cultivars. Disease suppression was greater when full fungicide rates were applied preventatively; however, yields between fungicide treated plots were similar. Lower levels of disease and higher yields were achieved with the partially resistant cultivar Tamrun OL07 compared to the susceptible cultivars Flavor Runner 458 and Tamrun OL 02. Despite possessing improved resistance Tamrun OL07 responded to all fungicide applications. While similar levels of disease control were achieved with broadcast or banded applications made during the day or at night, the yield response for the different application methods was inconsistent among years. A negative relationship (slope = −73.8; R2=0.73; P<0.01 was observed between final disease incidence ratings and yield data from studies where a fungicide response was observed. These studies suggest that both boscalid and fluazinam are effective at controlling Sclerotinia blight in peanuts. Alternative management strategies such as nighttime and banded applications could allow for lower fungicide rates to be used; however, additional studies are warranted.

  17. Population density of Beauveria bassiana in soil under the action of fungicides and native microbial populations

    Directory of Open Access Journals (Sweden)

    Flávia Barbosa Soares

    2017-08-01

    Full Text Available This study investigated whether populations of naturally-occurring soil bacteria, fungi and actinomycetes influence the effect of fungicides on the survival and growth of Beauveria bassiana. The toxicity of methyl thiophanate, pyraclostrobin, mancozeb and copper oxychloride at the recommended doses was analyzed in culture medium and in soil inoculated with fungus at various time points after addition of fungicides. All fungicides completely inhibited the growth and sporulation of B. bassiana in the culture medium. The fungicides were less toxic in soil, emphasizing the action of the microbial populations, which interfered with the toxic effects of these products to the fungus. Actinomycetes had the greatest influence on the entomopathogen, inhibiting it or degrading the fungicides to contribute to the survival and growth of B. bassiana in soil. Native populations of fungi and bacteria had a smaller influence on the population density of B. bassiana and the action of fungicides towards entomopathogen. The toxic effect of the fungicides was greater when added to the soil one hour before or after inoculation than at 48h after inoculation.

  18. Chemical management in fungicide sensivity of Mycosphaerella fijiensis collected from banana fields in México

    Directory of Open Access Journals (Sweden)

    Alejandra Aguilar-Barragan

    2014-01-01

    Full Text Available The chemical management of the black leaf streak disease in banana caused by Mycosphaerella fijiensis (Morelet requires numerous applications of fungicides per year. However this has led to fungicide resistance in the field. The present study evaluated the activities of six fungicides against the mycelial growth by determination of EC50 values of strains collected from fields with different fungicide management programs: Rustic management (RM without applications and Intensive management (IM more than 25 fungicide application/year. Results showed a decreased sensitivity to all fungicides in isolates collected from IM. Means of EC50 values in mg L-1 for RM and IM were: 13.25 ± 18.24 and 51.58 ± 46.14 for azoxystrobin, 81.40 ± 56.50 and 1.8575 ± 2.11 for carbendazim, 1.225 ± 0.945 and 10.01 ± 8.55 for propiconazole, 220 ± 67.66 vs. 368 ± 62.76 for vinclozolin, 9.862 ± 3.24 and 54.5 ± 21.08 for fludioxonil, 49.2125 ± 34.11 and 112.25 ± 51.20 for mancozeb. A molecular analysis for β-tubulin revealed a mutation at codon 198 in these strains having an EC50 greater than 10 mg L-1 for carbendazim. Our data indicate a consistency between fungicide resistance and intensive chemical management in banana fields, however indicative values for resistance were also found in strains collected from rustic fields, suggesting that proximity among fields may be causing a fungus interchange, where rustic fields are breeding grounds for development of resistant strains. Urgent actions are required in order to avoid fungicide resistance in Mexican populations of M. fijiensis due to fungicide management practices.

  19. Chemical management in fungicide sensitivity of Mycosphaerella fijiensis collected from banana fields in México.

    Science.gov (United States)

    Aguilar-Barragan, Alejandra; García-Torres, Ana Elisa; Odriozola-Casas, Olga; Macedo-Raygoza, Gloria; Ogura, Tetsuya; Manzo-Sánchez, Gilberto; James, Andrew C; Islas-Flores, Ignacio; Beltrán-García, Miguel J

    2014-01-01

    The chemical management of the black leaf streak disease in banana caused by Mycosphaerella fijiensis (Morelet) requires numerous applications of fungicides per year. However this has led to fungicide resistance in the field. The present study evaluated the activities of six fungicides against the mycelial growth by determination of EC50 values of strains collected from fields with different fungicide management programs: Rustic management (RM) without applications and Intensive management (IM) more than 25 fungicide application/year. Results showed a decreased sensitivity to all fungicides in isolates collected from IM. Means of EC50 values in mg L(-1) for RM and IM were: 13.25 ± 18.24 and 51.58 ± 46.14 for azoxystrobin, 81.40 ± 56.50 and 1.8575 ± 2.11 for carbendazim, 1.225 ± 0.945 and 10.01 ± 8.55 for propiconazole, 220 ± 67.66 vs. 368 ± 62.76 for vinclozolin, 9.862 ± 3.24 and 54.5 ± 21.08 for fludioxonil, 49.2125 ± 34.11 and 112.25 ± 51.20 for mancozeb. A molecular analysis for β-tubulin revealed a mutation at codon 198 in these strains having an EC50 greater than 10 mg L(-1) for carbendazim. Our data indicate a consistency between fungicide resistance and intensive chemical management in banana fields, however indicative values for resistance were also found in strains collected from rustic fields, suggesting that proximity among fields may be causing a fungus interchange, where rustic fields are breeding grounds for development of resistant strains. Urgent actions are required in order to avoid fungicide resistance in Mexican populations of M. fijiensis due to fungicide management practices.

  20. Chemical management in fungicide sensivity of Mycosphaerella fijiensis collected from banana fields in México

    Science.gov (United States)

    Aguilar-Barragan, Alejandra; García-Torres, Ana Elisa; Odriozola-Casas, Olga; Macedo-Raygoza, Gloria; Ogura, Tetsuya; Manzo-Sánchez, Gilberto; James, Andrew C.; Islas-Flores, Ignacio; Beltrán-García, Miguel J.

    2014-01-01

    The chemical management of the black leaf streak disease in banana caused by Mycosphaerella fijiensis (Morelet) requires numerous applications of fungicides per year. However this has led to fungicide resistance in the field. The present study evaluated the activities of six fungicides against the mycelial growth by determination of EC50 values of strains collected from fields with different fungicide management programs: Rustic management (RM) without applications and Intensive management (IM) more than 25 fungicide application/year. Results showed a decreased sensitivity to all fungicides in isolates collected from IM. Means of EC50 values in mg L−1 for RM and IM were: 13.25 ± 18.24 and 51.58 ± 46.14 for azoxystrobin, 81.40 ± 56.50 and 1.8575 ± 2.11 for carbendazim, 1.225 ± 0.945 and 10.01 ± 8.55 for propiconazole, 220 ± 67.66 vs. 368 ± 62.76 for vinclozolin, 9.862 ± 3.24 and 54.5 ± 21.08 for fludioxonil, 49.2125 ± 34.11 and 112.25 ± 51.20 for mancozeb. A molecular analysis for β-tubulin revealed a mutation at codon 198 in these strains having an EC50 greater than 10 mg L−1 for carbendazim. Our data indicate a consistency between fungicide resistance and intensive chemical management in banana fields, however indicative values for resistance were also found in strains collected from rustic fields, suggesting that proximity among fields may be causing a fungus interchange, where rustic fields are breeding grounds for development of resistant strains. Urgent actions are required in order to avoid fungicide resistance in Mexican populations of M. fijiensis due to fungicide management practices. PMID:24948956

  1. Employment effects of minimum wages

    OpenAIRE

    Neumark, David

    2014-01-01

    The potential benefits of higher minimum wages come from the higher wages for affected workers, some of whom are in low-income families. The potential downside is that a higher minimum wage may discourage employers from using the low-wage, low-skill workers that minimum wages are intended to help. Research findings are not unanimous, but evidence from many countries suggests that minimum wages reduce the jobs available to low-skill workers.

  2. Endocrine disrupting properties in vivo of widely used azole fungicides

    DEFF Research Database (Denmark)

    Taxvig, Camilla; Vinggaard, Anne; Hass, Ulla

    2008-01-01

    The endocrine-disrupting potential of four commonly used azole fungicides, propiconazole, tebuconazole, epoxiconazole and ketoconazole, were tested in two short-term in vivo studies. Initially, the antiandrogenic effects of propiconazole and tebuconazole (50, 100 and 150 mg/kg body weight/day each......) were examined in the Hershberger assay. In the second study, pregnant Wistar rats were dosed with propiconazole, tebuconazole, epoxiconazole or ketoconazole (50 mg/kg/day each) from gestational day (GD) 7 to GD 21. Caesarian sections were performed on dams at GD 21. Tebuconazole and propiconazole...... demonstrated no antiandrogenic effects at doses between 50 and 150 mg/kg body weight/day in the Hershberger assay. In the in utero exposure toxicity study, ketoconazole, a pharmaceutical to treat human fungal infections, decreased anogenital distance and reduced testicular testosterone levels, demonstrating...

  3. Field efficacy of different fungicide mixtures in control of net blotch on barley

    Directory of Open Access Journals (Sweden)

    Stepanović Miloš

    2016-01-01

    Full Text Available Seven fungicide mixtures (epoxiconazol + metconazole, boscalid + epoxiconazole, pyraclostrobin + epoxiconazole, prothioconazole + tebuconazole, picoxistrobin + cyproconazole, azoxystrobin + cyproconazole and spiroxamine + tebuconazole + triadimenol were evaluated for control of net blotch of barley caused by Drechslera teres, as well as yield losses, over the 2010 and 2011 growing seasons. Two applications of the fungicide combination pyraclostrobin + epoxiconazole at the rate of 1.0 l ha-1 were the most effective treatment in controlling the disease and improving yield in both experimental years. Treatments with the fungicide mixtures epoxiconazol + metconazole and spiroxamine + tebuconazole + triadimenol showed the least effectiveness in disease control, as well as yield increase.

  4. 75 FR 6151 - Minimum Capital

    Science.gov (United States)

    2010-02-08

    ... capital and reserve requirements to be issued by order or regulation with respect to a product or activity... minimum capital requirements. Section 1362(a) establishes a minimum capital level for the Enterprises... entities required under this section.\\6\\ \\3\\ The Bank Act's current minimum capital requirements apply to...

  5. Degradation alternatives for a commercial fungicide in water: biological, photo-Fenton, and coupled biological photo-Fenton processes.

    Science.gov (United States)

    López-Loveira, Elsa; Ariganello, Federico; Medina, María Sara; Centrón, Daniela; Candal, Roberto; Curutchet, Gustavo

    2017-11-01

    Imazalil (IMZ) is a widely used fungicide for the post-harvest treatment of citrus, classified as "likely to be carcinogenic in humans" for EPA, that can be only partially removed by conventional biological treatment. Consequently, specific or combined processes should be applied to prevent its release to the environment. Biological treatment with adapted microorganism consortium, photo-Fenton, and coupled biological photo-Fenton processes were tested as alternatives for the purification of water containing high concentration of the fungicide and the coadjutants present in the commercial formulation. IMZ-resistant consortium with the capacity to degrade IMZ in the presence of a C-rich co-substrate was isolated from sludge coming from a fruit packaging company wastewater treatment plant. This consortium was adapted to resist and degrade the organics present in photo-Fenton-oxidized IMZ water solution. Bacteria colonies from the consortia were isolated and identified. The effect of H 2 O 2 initial concentration and dosage on IMZ degradation rate, average oxidation state (AOS), organic acid concentration, oxidation, and mineralization percentage after photo-Fenton process was determined. The application of biological treatment to the oxidized solutions notably decreased the total organic carbon (TOC) in solution. The effect of the oxidation degree, limited by H 2 O 2 concentration and dosage, on the percentage of mineralization obtained after the biological treatment was determined and explained in terms of changes in AOS. The concentration of H 2 O 2 necessary to eliminate IMZ by photo-Fenton and to reduce TOC and chemical oxygen demand (COD) by biological treatment, in order to allow the release of the effluents to rivers with different flows, was estimated.

  6. Enzymatic basis for fungicide removal by Elodea canadensis.

    Science.gov (United States)

    Dosnon-Olette, Rachel; Schröder, Peter; Bartha, Bernadett; Aziz, Aziz; Couderchet, Michel; Eullaffroy, Philippe

    2011-07-01

    Plants can absorb a diversity of natural and man-made toxic compounds for which they have developed diverse detoxification mechanisms. Plants are able to metabolize and detoxify a wide array of xenobiotics by oxidation, sugar conjugation, glutathione conjugation, and more complex reactions. In this study, detoxification mechanisms of dimethomorph, a fungicide currently found in aquatic media were investigated in Elodea canadensis. Cytochrome P450 (P450) activity was measured by an oxygen biosensor system, glucosyltransferases (GTs) by HPLC, glutathione S-transferases (GSTs), and ascorbate peroxidase (APOX) were assayed spectrophotometrically. Incubation of Elodea with dimethomorph induced an increase of the P450 activity. GST activity was not stimulated by dimethomorph suggesting that GST does not participate in dimethomorph detoxification. In plants exposed to dimethomorph, comparable responses were observed for GST and APOX activities showing that the GST was more likely to play a role in response to oxidative stress. Preincubation with dimethomorph induced a high activity of O- and N-GT, it is therefore likely that both enzymes participate in the phase II (conjugation) of dimethomorph detoxification process. For the first time in aquatic plants, P450 activity was shown to be induced by a fungicide suggesting a role in the metabolization of dimethomorph. Moreover, our finding is the first evidence of dimethomorph and isoproturon activation of cytochrome P450 multienzyme family in an aquatic plant, i.e., Elodea (isoproturon was taken here as a reference molecule). The detoxification of dimetomorph seems to proceed via hydroxylation, and subsequent glucosylation, and might yield soluble as well as cell wall bound residues.

  7. Effects of Fungicides on Rat’s Neurosteroid Synthetic Enzymes

    Directory of Open Access Journals (Sweden)

    Xiuwei Shen

    2017-01-01

    Full Text Available Exposure to environmental endocrine disruptors may interfere with nervous system’s activity. Fungicides such as tebuconazole, triadimefon, and vinclozolin have antifungal activities and are used to prevent fungal infections in agricultural plants. In the present study, we studied effects of tebuconazole, triadimefon, and vinclozolin on rat’s neurosteroidogenic 5α-reductase 1 (5α-Red1, 3α-hydroxysteroid dehydrogenase (3α-HSD, and retinol dehydrogenase 2 (RDH2. Rat’s 5α-Red1, 3α-HSD, and RDH2 were cloned and expressed in COS-1 cells, and effects of these fungicides on them were measured. Tebuconazole and triadimefon competitively inhibited 5α-Red1, with IC50 values of 8.670 ± 0.771 × 10−6 M and 17.390 ± 0.079 × 10−6 M, respectively, while vinclozolin did not inhibit the enzyme at 100 × 10−6 M. Triadimefon competitively inhibited 3α-HSD, with IC50 value of 26.493 ± 0.076 × 10−6 M. Tebuconazole and vinclozolin weakly inhibited 3α-HSD, with IC50 values about 100 × 10−6 M, while vinclozolin did not inhibit the enzyme even at 100 × 10−6 M. Tebuconazole and triadimefon weakly inhibited RDH2 with IC50 values over 100 × 10−6 M and vinclozolin did not inhibit this enzyme at 100 × 10−6 M. Docking study showed that tebuconazole, triadimefon, and vinclozolin bound to the steroid-binding pocket of 3α-HSD. In conclusion, triadimefon potently inhibited rat’s neurosteroidogenic enzymes, 5α-Red1 and 3α-HSD.

  8. Foliar application of pyraclostrobin fungicide enhances the growth, rhizobial-nodule formation and nitrogenase activity in soybean (var. JS-335).

    Science.gov (United States)

    Joshi, Juhie; Sharma, Sonika; Guruprasad, K N

    2014-09-01

    A field study was conducted to investigate the impact of the fungicide pyraclostrobin (F500 - Headline®; a.i. 20%) on the activity of nitrogenase in soybean (var. JS-335). Pyraclostrobin (F500) was applied on the leaves of soybean plants at 10 and 20 days after emergence (DAE) of seedlings at concentrations ranging from 0.05% to 1%. Leghemoglobin (Lb) content and nitrogenase activity in root nodules were analyzed at 45(th)day after emergence of seedlings indicated a remarkable increase in Lb content and enhanced activity of nitrogenase in the root nodules of pyraclostrobin treated plants. The fungicide also enhanced the number of nodules along with weight of nodules, root biomass and growth of shoot and leaves. Enhanced nitrogen fixation in the root nodules by pyraclostrobin improves the growth of the plant in soybean before flowering and pod formation which ultimately resulted in yield and yield attributes. These results suggest that pyraclostrobin (F500) can be successfully employed as a foliar spray under field conditions to enhance the growth, nitrogen assimilation and hence yield of soybean. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Carbon-Based Fe3O4 Nanocomposites Derived from Waste Pomelo Peels for Magnetic Solid-Phase Extraction of 11 Triazole Fungicides in Fruit Samples

    Science.gov (United States)

    Ren, Keyu; Zhang, Wenlin; Cao, Shurui; Wang, Guomin; Zhou, Zhiqin

    2018-01-01

    Carbon-based Fe3O4 nanocomposites (C/Fe3O4 NCs) were synthesized by a simple one-step hydrothermal method using waste pomelo peels as the carbon precursors. The characterization results showed that they had good structures and physicochemical properties. The prepared C/Fe3O4 NCs could be applied as excellent and recyclable adsorbents for magnetic solid phase extraction (MSPE) of 11 triazole fungicides in fruit samples. In the MSPE procedure, several parameters including the amount of adsorbents, extraction time, the type and volume of desorption solvent, and desorption time were optimized in detail. Under the optimized conditions, the good linearity (R2 > 0.9916), the limits of detection (LOD), and quantification (LOQ) were obtained in the range of 1–100, 0.12–0.55, and 0.39–1.85 μg/kg for 11 pesticides, respectively. Lastly, the proposed MSPE method was successfully applied to analyze triazole fungicides in real apple, pear, orange, peach, and banana samples with recoveries in the range of 82.1% to 109.9% and relative standard deviations (RSDs) below 8.4%. Therefore, the C/Fe3O4 NCs based MSPE method has a great potential for isolating and pre-concentrating trace levels of triazole fungicides in fruits. PMID:29734765

  10. Degradation of the fungicide carbendazim in aqueous solutions with UV/TiO{sub 2} process: Optimization, kinetics and toxicity studies

    Energy Technology Data Exchange (ETDEWEB)

    Saien, J. [Department of Applied Chemistry, Bu-Ali Sina University, Hamedan 65174 (Iran, Islamic Republic of)], E-mail: saien@basu.ac.ir; Khezrianjoo, S. [Department of Applied Chemistry, Bu-Ali Sina University, Hamedan 65174 (Iran, Islamic Republic of)

    2008-09-15

    An attempt was made to investigate the potential of UV-photocatalytic process in the presence of TiO{sub 2} particles for the degradation of carbendazim (C{sub 9}H{sub 9}N{sub 3}O{sub 2}), a fungicide with a high worldwide consumption but considered as a 'priority hazard substance' by the Water Framework Directive of the European Commission (WFDEC). A circulating upflow photo-reactor was employed and the influence of catalyst concentration, pH and temperature were investigated. The results showed that degradation of this fungicide can be conducted in the both processes of only UV-irradiation and UV/TiO{sub 2}; however, the later provides much better results. Accordingly, a degradation of more than 90% of fungicide was achieved by applying the optimal operational conditions of 70 mg L{sup -1} of catalyst, natural pH of 6.73 and ambient temperature of 25 deg. C after 75 min irradiation. Under these mild conditions, the initial rate of degradation can be described well by the Langmuir-Hinshelwood kinetic model. Toxicological assessments on the obtained samples were also performed by measurement of the mycelium growth inhibition of Fusarium oxysporum fungus on PDA medium. The results indicate that the kinetics of degradation and toxicity are in reasonably good agreement mainly after 45 min of irradiation; confirming the effectiveness of photocatalytic process.

  11. Metabolite profiles of striped marsh frog (Limnodynastes peronii) larvae exposed to the anti-androgenic fungicides vinclozolin and propiconazole are consistent with altered steroidogenesis and oxidative stress.

    Science.gov (United States)

    Melvin, Steven D; Leusch, Frederic D L; Carroll, Anthony R

    2018-06-01

    Amphibians use wetlands in urban and agricultural landscapes for breeding, growth and development. Fungicides and other pesticides used in these areas have therefore been identified as potential threats that could contribute towards amphibian population declines. However, relatively little is known about how such chemicals influence sensitive early life-stages or how short episodic exposures influence sub-lethal physiological and metabolic pathways. The present study applied untargeted metabolomics to evaluate effects in early post-hatch amphibian larvae exposed to the anti-androgenic fungicides vinclozolin and propiconazole. Recently hatched (Gosner developmental stage 25) striped marsh frog (Limnodynastes peronii) larvae were exposed for 96 h to vinclozolin at 17.5, 174.8 and 1748.6 nM and propiconazole at 5.8, 58.4 and 584.4 nM. Nuclear Magnetic Resonance (NMR) spectroscopy was performed on polar metabolites obtained from whole-body extracts. Both fungicides altered metabolite profiles compared to control animals at all concentrations tested, and there were notable differences between the two chemicals. Overall responses were consistent with altered steroidogenesis and/or cholesterol metabolism, with inconsistent responses between the two fungicides likely reflecting minor differences in the mechanisms of action of these chemicals. Broad down-regulation of the tricarboxylic acid (TCA) cycle was also observed and is indicative of oxidative stress. Interestingly, formic acid was significantly increased in larvae exposed to vinclozolin but not propiconazole, suggesting this metabolite may serve as a useful biomarker of exposure to androgen-receptor binding anti-androgenic contaminants. This study demonstrates the power of untargeted metabolomics for distinguishing between similarly acting, but distinct, pollutants and for unraveling non-endocrine responses resulting from exposure to known endocrine active contaminants. Copyright © 2018 Elsevier B.V. All

  12. Synthesis and Fungicidal activity of some sulphide derivatives of O-Ethyl-N-substituted phenylcarbamates

    International Nuclear Information System (INIS)

    Imeokparia, F.A.

    2006-01-01

    Monosulphides of O-ethyl-N-substituted phenylcarbamates were prepared by the reaction between O-ethyl-N-substituted phenylcarbamates and sulphur dichloride, while the corresponding disulphides were prepared by the reaction between O-ethyl-N-substituted phenylcarbamates and sulphur monochloride. The synthesized compounds were characterized by elemental analysis, thin layer chromatography (TLC), Fourier-transform infrared, and /sup 1/H and /sup 13/C nuclear magnetic resonance spectroscopic techniques. In vitro fungicidal assay of these sulphides against Fusarium oxysporum, Aspergillus niger, Aspergillus flavus and Rhizopus stolonifer showed that they had Greater fungicidal activity than their parent carbamates. The synthesized sulphides were more active towards A. Niger and A. flavus. Unlike the parent carbamates, the type of substituents attached to the aromatic nucleus of these sulphides had little or no effect on their fungicidal activity as there was insignificant variation in the fungicidal activity of the monosulphide and the disulphide derivatives of O-ethyl-N-substituted phenylcarbamates. (author)

  13. Yield of Potato as Influenced by Crop Sanitation and Reduced Fungicidal Treatments

    Directory of Open Access Journals (Sweden)

    Fontem, DA.

    1995-01-01

    Full Text Available The effects of crop sanitation and reduced sprays of "Ridomil plus®" (12 % metalaxyl + 60 % cuprous oxide on the control of potato (Solanum tuberosum late blight caused by Phytophthora infestans were evaluated in two field experiments in 1993 in Dschang, Cameroon. In the first experiment, sanitation (five weekly removals of blighted leaves and two fungicidal treatments were initiated from first symptoms. In the second experiment, both fungicidal sprays were made at varying rates. Marketable yields increased by 50 % in sanitation-treated plots, by 94 % in plots sprayed with Ridomil plus (2.24 kg a. i./ha, or by 55 % in those exposed to both control methods. The fungicide equivalence of the sanitation treatment was two sprays of Ridomil plus at 0.76 kg a. i./ha. These results suggest that proper removal of diseased leaves or reduced fungicidal protection may be an effective late blight control method in potato farming.

  14. RAMAN SPECTROSCOPY-BASED METABOLOMICS FOR DIFFERENTIATING EXPOSURES TO TRIAZOLE FUNGICIDES USING RAT URINE

    Science.gov (United States)

    Normal Raman spectroscopy was evaluated as a metabolomic tool for assessing the impacts of exposure to environmental contaminants, using rat urine collected during the course of a toxicological study. Specifically, one of three triazole fungicides, myclobutanil, propiconazole or ...

  15. Effects of Artea, a systemic fungicide, on the antioxidant system and ...

    African Journals Online (AJOL)

    Effects of Artea, a systemic fungicide, on the antioxidant system and the respiratory activity of durum wheat ( Triticum durum L .). ... African Journal of Biotechnology ... Root respiratory activity was also determined using a polarographic method ...

  16. Modulators of membrane drug transporters potentiate the activity of the DMI fungicide oxpoconazole against Botrytis cinerea

    NARCIS (Netherlands)

    Hayashi, K.; Schoonbeek, H.; Waard, de M.A.

    2003-01-01

    Modulators known to reduce multidrug resistance in tumour cells were tested for their potency to synergize the fungitoxic activity of the fungicide oxpoconazole, a sterol demethylation inhibitor (DMI), against Botrytis cinerea Pers. Chlorpromazine, a phenothiazine compound known as a calmodulin

  17. Efficacy of Strobilurin-related and Multi-site Fungicide Mixtures Against Apple Scab

    Directory of Open Access Journals (Sweden)

    Emil Rekanović

    2007-01-01

    Full Text Available The efficacy of several fungicide mixtures in controlling Venturia inaequalis in apple was evaluated in field trials. The efficacies of Flint Plus (trifloxystrobin + captan and Tercel (pyraclostrobin+ dithianon in comparison with standard fungicides Zato 50-WG (trifloxystrobin and Stroby + Delan (kresoxim-methyl + dithianon were tested in the localities Mihajlovac, Radmilovac and Landol in 2004 and 2005. Both tested fungicides exhibited high efficacy in controlling apple scab. There were significant differencies in the efficacies of Flint Plus (91.3-98.5% and Zato 50-WG (68.2% and 78.4%; and Tercel (88.7-93.5% and Stroby + Delan (77.9% and 82.1%. Our experiments showed that the investigated fungicide mixtures arehighly effective against V. inaqeulais, even under high disease pressure.

  18. Effects of Sublethal Fungicides on Mutation Rates and Genomic Variation in Fungal Plant Pathogen, Sclerotinia sclerotiorum.

    Science.gov (United States)

    Amaradasa, B Sajeewa; Everhart, Sydney E

    2016-01-01

    Pathogen exposure to sublethal doses of fungicides may result in mutations that may represent an important and largely overlooked mechanism of introducing new genetic variation into strictly clonal populations, including acquisition of fungicide resistance. We tested this hypothesis using the clonal plant pathogen, Sclerotinia sclerotiorum. Nine susceptible isolates were exposed independently to five commercial fungicides with different modes of action: boscalid (respiration inhibitor), iprodione (unclear mode of action), thiophanate methyl (inhibition of microtubulin synthesis) and azoxystrobin and pyraclostrobin (quinone outside inhibitors). Mycelium of each isolate was inoculated onto a fungicide gradient and sub-cultured from the 50-100% inhibition zone for 12 generations and experiment repeated. Mutational changes were assessed for all isolates at six neutral microsatellite (SSR) loci and for a subset of isolates using amplified fragment length polymorphisms (AFLPs). SSR analysis showed 12 of 85 fungicide-exposed isolates had a total of 127 stepwise mutations with 42 insertions and 85 deletions. Most stepwise deletions were in iprodione- and azoxystrobin-exposed isolates (n = 40/85 each). Estimated mutation rates were 1.7 to 60-fold higher for mutated loci compared to that expected under neutral conditions. AFLP genotyping of 33 isolates (16 non-exposed control and 17 fungicide exposed) generated 602 polymorphic alleles. Cluster analysis with principal coordinate analysis (PCoA) and discriminant analysis of principal components (DAPC) identified fungicide-exposed isolates as a distinct group from non-exposed control isolates (PhiPT = 0.15, P = 0.001). Dendrograms based on neighbor-joining also supported allelic variation associated with fungicide-exposure. Fungicide sensitivity of isolates measured throughout both experiments did not show consistent trends. For example, eight isolates exposed to boscalid had higher EC50 values at the end of the experiment, and

  19. Effects of Sublethal Fungicides on Mutation Rates and Genomic Variation in Fungal Plant Pathogen, Sclerotinia sclerotiorum.

    Directory of Open Access Journals (Sweden)

    B Sajeewa Amaradasa

    Full Text Available Pathogen exposure to sublethal doses of fungicides may result in mutations that may represent an important and largely overlooked mechanism of introducing new genetic variation into strictly clonal populations, including acquisition of fungicide resistance. We tested this hypothesis using the clonal plant pathogen, Sclerotinia sclerotiorum. Nine susceptible isolates were exposed independently to five commercial fungicides with different modes of action: boscalid (respiration inhibitor, iprodione (unclear mode of action, thiophanate methyl (inhibition of microtubulin synthesis and azoxystrobin and pyraclostrobin (quinone outside inhibitors. Mycelium of each isolate was inoculated onto a fungicide gradient and sub-cultured from the 50-100% inhibition zone for 12 generations and experiment repeated. Mutational changes were assessed for all isolates at six neutral microsatellite (SSR loci and for a subset of isolates using amplified fragment length polymorphisms (AFLPs. SSR analysis showed 12 of 85 fungicide-exposed isolates had a total of 127 stepwise mutations with 42 insertions and 85 deletions. Most stepwise deletions were in iprodione- and azoxystrobin-exposed isolates (n = 40/85 each. Estimated mutation rates were 1.7 to 60-fold higher for mutated loci compared to that expected under neutral conditions. AFLP genotyping of 33 isolates (16 non-exposed control and 17 fungicide exposed generated 602 polymorphic alleles. Cluster analysis with principal coordinate analysis (PCoA and discriminant analysis of principal components (DAPC identified fungicide-exposed isolates as a distinct group from non-exposed control isolates (PhiPT = 0.15, P = 0.001. Dendrograms based on neighbor-joining also supported allelic variation associated with fungicide-exposure. Fungicide sensitivity of isolates measured throughout both experiments did not show consistent trends. For example, eight isolates exposed to boscalid had higher EC50 values at the end of the

  20. Effects of Sublethal Fungicides on Mutation Rates and Genomic Variation in Fungal Plant Pathogen, Sclerotinia sclerotiorum

    Science.gov (United States)

    Amaradasa, B. Sajeewa

    2016-01-01

    Pathogen exposure to sublethal doses of fungicides may result in mutations that may represent an important and largely overlooked mechanism of introducing new genetic variation into strictly clonal populations, including acquisition of fungicide resistance. We tested this hypothesis using the clonal plant pathogen, Sclerotinia sclerotiorum. Nine susceptible isolates were exposed independently to five commercial fungicides with different modes of action: boscalid (respiration inhibitor), iprodione (unclear mode of action), thiophanate methyl (inhibition of microtubulin synthesis) and azoxystrobin and pyraclostrobin (quinone outside inhibitors). Mycelium of each isolate was inoculated onto a fungicide gradient and sub-cultured from the 50–100% inhibition zone for 12 generations and experiment repeated. Mutational changes were assessed for all isolates at six neutral microsatellite (SSR) loci and for a subset of isolates using amplified fragment length polymorphisms (AFLPs). SSR analysis showed 12 of 85 fungicide-exposed isolates had a total of 127 stepwise mutations with 42 insertions and 85 deletions. Most stepwise deletions were in iprodione- and azoxystrobin-exposed isolates (n = 40/85 each). Estimated mutation rates were 1.7 to 60-fold higher for mutated loci compared to that expected under neutral conditions. AFLP genotyping of 33 isolates (16 non-exposed control and 17 fungicide exposed) generated 602 polymorphic alleles. Cluster analysis with principal coordinate analysis (PCoA) and discriminant analysis of principal components (DAPC) identified fungicide-exposed isolates as a distinct group from non-exposed control isolates (PhiPT = 0.15, P = 0.001). Dendrograms based on neighbor-joining also supported allelic variation associated with fungicide-exposure. Fungicide sensitivity of isolates measured throughout both experiments did not show consistent trends. For example, eight isolates exposed to boscalid had higher EC50 values at the end of the experiment

  1. Sensitivity of some nitrogen fixers and the target pest Fusarium oxysporum to fungicide thiram

    OpenAIRE

    Osman, Awad G.; Sherif, Ashraf M.; Elhussein, Adil A.; Mohamed, Afrah T.

    2012-01-01

    This study was carried out to investigate the toxic effects of the fungicide thiram (TMTD) against five nitrogen fixers and the thiram target pest Fusarium oxysporum under laboratory conditions. Nitrogen fixing bacteria Falvobacterium showed the highest values of LD50 and proved to be the most resistant to the fungicide followed by Fusarium oxysporum, while Pseudomonas aurentiaca was the most affected microorganism. LD50 values for these microorganisms were in 2–5 orders of magnitude lower in...

  2. Effects of azole fungicides on the function of sex and thyroid hormones

    DEFF Research Database (Denmark)

    Kjærstad, Mia Birkhøj; Andersen, Helle Raun; Taxvig, Camilla

    Resumé: Azole-fungicides are frequently used in Denmark. Epoxiconazole, propiconazole, and tebuconazole had endocrine disrupting properties in cell based assays. In rats, epoxiconazole and tebuconazole increased gestational length, maternal progesterone level, and masculinized female-offspring. B......-offspring. Besides, tebuconazole caused feminization of male-offspring. Similar effects were previously demonstrated for prochloraz. The results indicate that azole-fungicides in general have endocrine disrupting properties...

  3. Fungicide application practices and personal protective equipment use among orchard farmers in the agricultural health study.

    Science.gov (United States)

    Hines, C J; Deddens, J A; Coble, J; Alavanja, M C R

    2007-04-01

    Fungicides are routinely applied to deciduous tree fruits for disease management. Seventy-four private orchard applicators enrolled in the Agricultural Health Study participated in the Orchard Fungicide Exposure Study in 2002-2003. During 144 days of observation, information was obtained on chemicals applied and applicator mixing, application, personal protective, and hygiene practices. At least half of the applicators had orchards with orchard applicators.

  4. Assessing the impact of fungicide enostroburin application on bacterial community in wheat phyllosphere.

    Science.gov (United States)

    Gu, Likun; Bai, Zhihui; Jin, Bo; Hu, Qing; Wang, Huili; Zhuang, Guoqiang; Zhang, Hongxun

    2010-01-01

    Fungicides have been used extensively for controlling fungal pathogens of plants. However, little is known regarding the effects that fungicides upon the indigenous bacterial communities within the plant phyllosphere. The aims of this study were to assess the impact of fungicide enostroburin upon bacterial communities in wheat phyllosphere. Culture-independent methodologies of 16S rDNA clone library and 16S rDNA directed polymerase chain reaction with denaturing gradient gel electrophoresis (PCR-DGGE) were used for monitoring the change of bacterial community. The 16S rDNA clone library and PCR-DGGE analysis both confirmed the microbial community of wheat plant phyllosphere were predominantly of the gamma-Proteobacteria phyla. Results from PCR-DGGE analysis indicated a significant change in bacterial community structure within the phyllosphere following fungicide enostroburin application. Bands sequenced within control cultures were predominantly of Pseudomonas genus, but those bands sequenced in the treated samples were predominantly strains of Pantoea genus and Pseudomonas genus. Of interest was the appearance of two DGGE bands following fungicide treatment, one of which had sequence similarities (98%) to Pantoea sp. which might be a competitor of plant pathogens. This study revealed the wheat phyllosphere bacterial community composition and a shift in the bacterial community following fungicide enostroburin application.

  5. In vitro colonial inhibition of an isolate from Colletotrichum acutatum Simmonds to fungicide treatments

    Directory of Open Access Journals (Sweden)

    Dagoberto Guillén Sánchez

    2018-02-01

    Full Text Available The aim of the research was to evaluate the in vitro sensitivity of Colletotrichum acutatum antracnosis to seven fungicides. It began with an isolate preserved in the ceparium of the Phytopathology Laboratory of the High School Studies of Xalostoc, Morelos. A completely randomized design was used to evaluate the fungicides benomyl, diphenoconazole, azoxystrobin, trifloxystrobin, copper oxychloride, fluoxastrobin and captan, at high, medium and low doses, for a total of 22 treatments with six repetitions. Sterile distilled water was applied to the control. The treatments were applied at a rate of 5 mL per plate, which contained PDA medium and a mycelial disc (Ø 5 mm. The inoculated plates were incubated at 24 °C, in 12 hour photoperiod. The colony diameter was measured every 24 hours and the percent inhibition was calculated. A bifactorial variance analysis was performed, according to Fungicide and Dose; and the differences between treatments were detected by the LSD test with 95 % confidence. The diameter of the colony and the percentage of inhibition did not show differences for dose levels, without significant effects for the interaction of both factors, fungicides, and dose. However, all doses of the different fungicides inhibited colony growth compared to the control. The benomyl, difenoconazol and captan fungicides were able to totally reduce the growth of the C. acutatum colony; followed by copper oxychloride, azoxystrobin, fluoxastrobin and trifloxystrobin in decreasing order. Only benomyl, difenoconazol, captan and copper oxychloride achieved more than 50 % inhibition.

  6. Esterase isozymes patterns of grape vine (Vitis vinifera L. are altered in response to fungicide exposure

    Directory of Open Access Journals (Sweden)

    Gleice Ribeiro Orasmo

    2015-10-01

    Full Text Available Current analysis characterizes the effect of different fungicides often applied for pest control on a-and b-esterase patterns of four economically important table-wine grape cultivars (Italia, Rubi, Benitaka and Brasil of Vitis vinifera. The a- and b-esterase patterns in bud leaves of the cultivars were assessed by native PAGE analysis. Cabrio Top® compound inhibited Est-2, Est-5, Est-6, Est-7, Est-8, Est-9 and Est-10 carboxylesterases, whereas Est-4, Est-11, Est-12, Est-13, Est-14 acetylesterases and Est-16 carboxylesterase were detected as weakly stained bands. Carboxylesterases and acetylesterases were also detected as weakly stained bands when exposed to fungicides Orthocide 500®, Positron Duo® and Folicur PM®. No changes in a- and b-esterase patterns were reported when the vines were exposed to the fungicides Rovral SC®, Kumulus DF®, Curzate M®, Score® or Cuprogarb 500®. The evidence of functional changes in carboxylesterase and acetylesterase levels in current study is a warning to grape producers on the dangers inherent in the indiscriminate use of potent and modern fungicides extensively used in agriculture. The inhibition effect of fungicides on esterase isozyme molecules seems to be independent of the fungicide chemical.

  7. In vitro response of phaeoramularia angolensis to commonly used fungicides in Kenya

    International Nuclear Information System (INIS)

    Juma, I.M.; Siboe, M.

    1996-01-01

    The leaf and fruit spot disease of citrus spp. caused by the fungus Phaeoramularia angolensis Kirk is new and epidemic in Kenya, with a 100% crop yield loss. Poor response to fungicide application led to the suspicion that the fungus was resistant to conventional fungicides, hence the difficulties experienced in its control. Therefore the study was carried out to establish wether P.angolensis isolates from Western Kenya were screened for resistance. The following fungicides were used: copper fungicides(Cupric hydroxide 50% WP or kocide 101 and copper oxychloride 50% WP), Mancozeb 70% WP (Dithane M45)and Propineb 80% WPC (Antracol). Mancozeb 70% WP and Propineb were the most effective with LD-5-0 at 0.03 ppm and 0.25 ppm respectively. Copper fungicide LD-5-0 was above 3000 ppm (current manufacturers' recommended dosage is 7,500 ppm and 6,900 ppm for kocide 101 and copper oxychloride respectively). There was no obvious evidence of resistance. The fungi- static characteristics of copper fungicides and the application of wrong dosage and timing could be the reason for the difficulties experienced in the control of the disease. (author) 14 refs., 2 tables, 1 graph

  8. Cytoplasmic fungal lipases release fungicides from ultra-deformable vesicular drug carriers.

    Directory of Open Access Journals (Sweden)

    Gero Steinberg

    Full Text Available The Transfersome® is a lipid vesicle that contains membrane softeners, such as Tween 80, to make it ultra-deformable. This feature makes the Transfersome® an efficient carrier for delivery of therapeutic drugs across the skin barrier. It was reported that TDT 067 (a topical formulation of 15 mg/ml terbinafine in Transfersome® vesicles has a much more potent antifungal activity in vitro compared with conventional terbinafine, which is a water-insoluble fungicide. Here we use ultra-structural studies and live imaging in a model fungus to describe the underlying mode of action. We show that terbinafine causes local collapse of the fungal endoplasmic reticulum, which was more efficient when terbinafine was delivered in Transfersome® vesicles (TFVs. When applied in liquid culture, fluorescently labeled TFVs rapidly entered the fungal cells (T(1/2~2 min. Entry was F-actin- and ATP-independent, indicating that it is a passive process. Ultra-structural studies showed that passage through the cell wall involves significant deformation of the vesicles, and depends on a high concentration of the surfactant Tween 80 in their membrane. Surprisingly, the TFVs collapsed into lipid droplets after entry into the cell and the terbinafine was released from their interior. With time, the lipid bodies were metabolized in an ATP-dependent fashion, suggesting that cytosolic lipases attack and degrade intruding TFVs. Indeed, the specific monoacylglycerol lipase inhibitor URB602 prevented Transfersome® degradation and neutralized the cytotoxic effect of Transfersome®-delivered terbinafine. These data suggest that (a Transfersomes deliver the lipophilic fungicide Terbinafine to the fungal cell wall, (b the membrane softener Tween 80 allows the passage of the Transfersomes into the fungal cell, and (c fungal lipases digest the invading Transfersome® vesicles thereby releasing their cytotoxic content. As this mode of action of Transfersomes is independent of the

  9. Methodology for determination of benzimidazolic fungicides residues in strawberry and lettuce by HPLC-DAD

    International Nuclear Information System (INIS)

    Dangond Araujo, Jose Jairo; Guerrero dallos, Jairo Arturo

    2006-01-01

    systemic fungicides like benzimidazolic compounds are used to protect several crops of fruits and vegetables. in this work a new method for analysis of Benomyl, carbendazim and thiabendazol in strawberry and lettuce by high performance liquid chromatography with diode array detector (HPLC-DAD) was validated. benomyl residues were determined after its conversion to carbendazim. pesticide residues were extracted from strawberry and lettuce samples with ethyl acetate and these extracts were cleaned up by gel permeation chromatography (GPC). final determination was carried out by HPLC-DAD in reverse phase column. the method is selective, specific, precise and accurate. the calibration curves show linearity over concentration range of 1.24 to 6.19 mg/kg, with detection limits of 0.40 and 0.27 mg/kg and quantification limits of 1.35 and 0.81 mg/kg for carbendazim and thiabendazole respectively. the recovery experiments yielding averages of 90 %. n o residues of these compounds were found in collected samples from specific areas of Cundinamarca, Colombia

  10. Gating in grapevine: Relationship between application of the fungicide fludioxonil and circadian rhythm on photosynthesis

    Energy Technology Data Exchange (ETDEWEB)

    Petit, Anne-Noelle [Laboratoire de Stress, Defenses et Reproduction des Plantes, URVVC-SE EA 2069, Universite de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Batiment 18, Moulin de la Housse, BP 1039, F-51687 REIMS Cedex 2 (France)], E-mail: petit081@etudiant.univ-reims.fr; Fontaine, Florence [Laboratoire de Stress, Defenses et Reproduction des Plantes, URVVC-SE EA 2069, Universite de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Batiment 18, Moulin de la Housse, BP 1039, F-51687 REIMS Cedex 2 (France)], E-mail: florence.fontaine@univ-reims.fr; Clement, Christophe [Laboratoire de Stress, Defenses et Reproduction des Plantes, URVVC-SE EA 2069, Universite de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Batiment 18, Moulin de la Housse, BP 1039, F-51687 REIMS Cedex 2 (France)], E-mail: christophe.clement@univ-reims.fr; Vaillant-Gaveau, Nathalie [Laboratoire de Stress, Defenses et Reproduction des Plantes, URVVC-SE EA 2069, Universite de Reims Champagne-Ardenne, UFR Sciences Exactes et Naturelles, Batiment 18, Moulin de la Housse, BP 1039, F-51687 REIMS Cedex 2 (France)], E-mail: nathalie.vaillant-gaveau@univ-reims.fr

    2009-01-15

    The aim of this study was to determine the impact of the fludioxonil (fdx) fungicide on the diurnal fluctuation in grapevine photosynthesis. Therefore, fdx treatment was performed at the end of flowering, at 8 am, 12 am or 7 pm. The study was performed in experimental field and several photosynthesis parameters were followed one day after treatment. Morning fdx treatment induced (i) a significant and simultaneous drop of both photosynthesis (Pn) and stomatal conductance between 8 am and 4 pm and (ii) an increase of intercellular CO{sub 2} concentration when compared to control plants. On the contrary, evening fdx treatment did not affect Pn whereas midday treatment caused Pn increase after 4 pm. These data suggest that (i) morning fdx treatment results in a non-stomatal limitation of Pn, (ii) midday treatment is more suitable to treat grapevine with fdx and (iii) a phenomenon of gating was noticed. - The period of fdx spraying was an important parameter in stress response: the midday fdx treatment is more suitable to treat grapevine with fdx.

  11. Gating in grapevine: Relationship between application of the fungicide fludioxonil and circadian rhythm on photosynthesis

    International Nuclear Information System (INIS)

    Petit, Anne-Noelle; Fontaine, Florence; Clement, Christophe; Vaillant-Gaveau, Nathalie

    2009-01-01

    The aim of this study was to determine the impact of the fludioxonil (fdx) fungicide on the diurnal fluctuation in grapevine photosynthesis. Therefore, fdx treatment was performed at the end of flowering, at 8 am, 12 am or 7 pm. The study was performed in experimental field and several photosynthesis parameters were followed one day after treatment. Morning fdx treatment induced (i) a significant and simultaneous drop of both photosynthesis (Pn) and stomatal conductance between 8 am and 4 pm and (ii) an increase of intercellular CO 2 concentration when compared to control plants. On the contrary, evening fdx treatment did not affect Pn whereas midday treatment caused Pn increase after 4 pm. These data suggest that (i) morning fdx treatment results in a non-stomatal limitation of Pn, (ii) midday treatment is more suitable to treat grapevine with fdx and (iii) a phenomenon of gating was noticed. - The period of fdx spraying was an important parameter in stress response: the midday fdx treatment is more suitable to treat grapevine with fdx

  12. The Fungicidal Activity of Thymol against Fusarium graminearum via Inducing Lipid Peroxidation and Disrupting Ergosterol Biosynthesis

    Directory of Open Access Journals (Sweden)

    Tao Gao

    2016-06-01

    Full Text Available Thymol is a natural plant-derived compound that has been widely used in pharmaceutical and food preservation applications. However, the antifungal mechanism for thymol against phytopathogens remains unclear. In this study, we identified the antifungal action of thymol against Fusarium graminearum, an economically important phytopathogen showing severe resistance to traditional chemical fungicides. The sensitivity of thymol on different F. graminearum isolates was screened. The hyphal growth, as well as conidial production and germination, were quantified under thymol treatment. Histochemical, microscopic, and biochemical approaches were applied to investigate thymol-induced cell membrane damage. The average EC50 value of thymol for 59 F. graminearum isolates was 26.3 μg·mL−1. Thymol strongly inhibited conidial production and hyphal growth. Thymol-induced cell membrane damage was indicated by propidium iodide (PI staining, morphological observation, relative conductivity, and glycerol measurement. Thymol induced a significant increase in malondialdehyde (MDA concentration and a remarkable decrease in ergosterol content. Taken together, thymol showed potential antifungal activity against F. graminearum due to the cell membrane damage originating from lipid peroxidation and the disturbance of ergosterol biosynthesis. These results not only shed new light on the antifungal mechanism of thymol, but also imply a promising alternative for the control of Fusarium head blight (FHB disease caused by F. graminearum.

  13. Fate and activity of fungal BCAs delivered to strawberry flowers and their potential for integration with fungicides

    DEFF Research Database (Denmark)

    Jensen, Birgit; Andersen, Birgitte; Thrane, Ulf

    2013-01-01

    Grey mold caused by Botrytis cinerea is a serious strawberry disease. Yield loss is prevented by repeated fungicide treatments during flowering which increases the risk of pesticide residues in berries. Fruit lesions are typically initiated from B. cinerea infected stamens or from dead infected......) the interaction between BCAs and B. cinerea on strawberry flowers, 2) the sensitivity of BCAs to strawberry fungicides, and 3) the effect of combined BCA+fungicide treatment on BCAs and on the indigenous mycobiota....

  14. Fenarimol, a Pyrimidine-Type Fungicide, Inhibits Brassinosteroid Biosynthesis

    Directory of Open Access Journals (Sweden)

    Keimei Oh

    2015-07-01

    Full Text Available The plant steroid hormone brassinosteroids (BRs are important signal mediators that regulate broad aspects of plant growth and development. With the discovery of brassinoazole (Brz, the first specific inhibitor of BR biosynthesis, several triazole-type BR biosynthesis inhibitors have been developed. In this article, we report that fenarimol (FM, a pyrimidine-type fungicide, exhibits potent inhibitory activity against BR biosynthesis. FM induces dwarfism and the open cotyledon phenotype of Arabidopsis seedlings in the dark. The IC50 value for FM to inhibit stem elongation of Arabidopsis seedlings grown in the dark was approximately 1.8 ± 0.2 μM. FM-induced dwarfism of Arabidopsis seedlings could be restored by brassinolide (BL but not by gibberellin (GA. Assessment of the target site of FM in BR biosynthesis by feeding BR biosynthesis intermediates indicated that FM interferes with the side chain hydroxylation of BR biosynthesis from campestanol to teasterone. Determination of the binding affinity of FM to purified recombinant CYP90D1 indicated that FM induced a typical type II binding spectrum with a Kd value of approximately 0.79 μM. Quantitative real-time PCR analysis of the expression level of the BR responsive gene in Arabidopsis seedlings indicated that FM induces the BR deficiency in Arabidopsis.

  15. Fungicidal effect of bacteriocins harvested from Bacillus spp.

    Directory of Open Access Journals (Sweden)

    Adetunji, V. O.

    2013-01-01

    Full Text Available Aims: This study investigated the ability of bacteriocins isolated from Bacillus spp. (Bacillus species to inhibit fourdifferent yeast isolates obtained from common food products (nono, yoghurt, ogi and cheese commonly consumed byNigerians with minimal heat treatment.Methodology and results: Forty-five Bacillus spp. was isolated and identified from common food products usingcultural, morphological, physiological and biochemical characteristics. These isolates were tested for antimicrobialactivity against Salmonella enteritidis (3, Micrococcus luteus (1 and Staphylococcus aureus (2. Eight bacteriocinproducing strains were identified from an over- night broth culture centrifugated at 3500 revolutions for five minutes.Fungicidal effects of these bacteriocins were tested against four yeast strains using the Agar Well Diffusion method. Thebacteriocins produced wide zones of inhibition ranging from 5.9±0.000 to 24.00±0.000 mm against the 4 yeast strainstested. There was a significant difference (at p<0.05 between the yeast organisms and the bacteriocins from theBacillus spp.Conclusion, significance and impact of study: The study reveals the antifungal property of bacteriocins from Bacillusspp. and serves therefore as a base for further studies in its use in the control of diseases and extension of shelf-life ofproducts prone to fungi contamination.

  16. Dissipation of the fungicide hexaconazole in oil palm plantation.

    Science.gov (United States)

    Maznah, Zainol; Halimah, Muhamad; Ismail, Sahid; Idris, Abu Seman

    2015-12-01

    Hexaconazole is a potential fungicide to be used in the oil palm plantation for controlling the basal stem root (BSR) disease caused by Ganoderma boninense. Therefore, the dissipation rate of hexaconazole in an oil palm agroecosystem under field conditions was studied. Two experimental plots were treated with hexaconazole at the recommended dosage of 4.5 g a.i. palm(-1) (active ingredient) and at double the recommended dosage (9.0 g a.i. palm(-1)), whilst one plot was untreated as control. The residue of hexaconazole was detected in soil samples in the range of 2.74 to 0.78 and 7.13 to 1.66 mg kg(-1) at the recommended and double recommended dosage plots, respectively. An initial relatively rapid dissipation rate of hexaconazole residues occurred but reduced with time. The dissipation of hexaconazole in soil was described using first-order kinetics with the value of coefficient regression (r (2) > 0.8). The results indicated that hexaconazole has moderate persistence in the soil and the half-life was found to be 69.3 and 86.6 days in the recommended and double recommended dosage plot, respectively. The results obtained highlight that downward movement of hexaconazole was led by preferential flow as shown in image analysis. It can be concluded that varying soil conditions, environmental factors, and pesticide chemical properties of hexaconazole has a significant impact on dissipation of hexaconazole in soil under humid conditions.

  17. Herbicidal and Fungicidal Activities of Lactones in Kava (Piper methysticum).

    Science.gov (United States)

    Xuan, T D; Elzaawely, A A; Fukuta, M; Tawata, S

    2006-02-08

    This is the first report showing that kava lactones are plant and plant fungus growth inhibitors. Aqueous extract of kava roots showed high allelopathic potential and strongly suppressed germination and growth of lettuce, radish, barnyardgrass, and monochoria. Nine kava lactones were detected using GC-MS including desmethoxyyagonin, kavain, 7,8-dihydrokavain, hydroxykavain, yagonin, 5,6,7,8-tetrahydroxyyagonin, methysticin, dihydromethysticin, and 11-hydroxy-12-methoxydihydrokavain. Quantities of desmethoxyyagonin, kavain, 7,8-dihydrokavain, yagonin, methysticin, and dihydromethysticin detected were 4.3, 6.9, 18.6, 5.7, 1.4, and 5.4 mg/g of dry weight, respectively. These six major lactones in kava roots showed great herbicidal and antifungal activities. Growth of lettuce and barnyardgrass were significantly inhibited at 1-10 ppm, and four plant fungi including Colletotrichum gloeosporides, Fusarium solani, Fusarium oxysporum, and Trichoderma viride were significantly inhibited at 10-50 ppm. The biological activities of kava lactones were characterized by different double-bond linkage patterns in positions 5,6 and 7,8. The findings of this study suggest that kava lactones may be useful for the development of bioactive herbicides and fungicides.

  18. Photoreduction of chlorothalonil fungicide on plant leaf models.

    Science.gov (United States)

    Monadjemi, S; El Roz, M; Richard, C; Ter Halle, A

    2011-11-15

    Photodegradation is seldom considered at the surface of vegetation after crop spraying. Chlorothalonil, a broad-spectrum foliar fungicide with a very widespread use worldwide, was considered. To represent the waxy upper layer of leaves, tests were performed within thin paraffin wax films or in n-heptane. Laser flash photolysis together with steady-state irradiation in n-heptane allowed the determination of the photodegradation mechanisms Chlorothalonil ability to produce singlet oxygen was measured; noteworthy its efficiency is close to 100%. Additionally, chlorothalonil photodegradation mainly proceeds through reductive dechlorination. In these hydrophobic media, a radical mechanism was evidenced. Photochemical tests on wax films under simulated solar light show that formulated chlorothalonil is more reactive than pure chlorothalonil. The field-extrapolated half-life of photolysis on vegetation was estimated to 5.3 days. This value was compared to the half-lives of penetration and volatilization available in the literature. It appears that chlorothalonil dissipation from crops is ruled by both photodegradation and penetration. The relative importance of the two paths probably depends on meteorological factors and on physicochemical characteristics of the crop leaf cuticle.

  19. Hydrogen peroxide as a fungicide for fish culture

    Science.gov (United States)

    Dawson, V.K.; Rach, J.J.; Schreier, Theresa M.

    1994-01-01

    Antifungal agents are needed to maintain healthy stocks of fish in the intensive culture systems currently employed in fish hatcheries. Malachite green has been the most widely used antifungal agent; however, its potential for producing teratology in animals and fish precludes further use in fish culture. Preliminary studies at the National Fisheries Research Center, La Crosse, WI, USA (La Crosse Center) indicate that hydrogen peroxide is effective for control of Saprolegnia sp. fungus on incubating eggs of rainbow trout. It is also effective against a wide variety of other organisms such as bacteria, yeasts, viruses, and spores, and has been proposed as a treatment for sea lice on salmon. Hydrogen peroxide and its primary decomposition products, oxygen and water, are not systemic poisons and are considered environmentally compatible. In response to a petition from the La Crosse Center, the U.S. Food and Drug Administration (FDA) recently classified hydrogen peroxide as a 'low regulatory priority' when used for control of fungus on fish and fish eggs. Preliminary tests conducted at the La Crosse Center suggest that prophylactic treatments of 250 to 500 ppm (based on 100% active ingredient) for 15 minutes every other day will inhibit fungal infections on healthy rainbow trout (Oncorhynchus mykiss) eggs. This treatment regime also seems to inhibit fungal development and increase hatching success among infected eggs. Efficacy and safety of hydrogen peroxide as a fungicide for fish are currently being evaluated.

  20. Aggregation-based colorimetric sensor for determination of prothioconazole fungicide using colloidal silver nanoparticles (AgNPs)

    Science.gov (United States)

    Ivrigh, Zahra Jafar-Nezhad; Fahimi-Kashani, Nafiseh; Hormozi-Nezhad, M. Reza

    2017-12-01

    There is a growing interest in developing high-performance sensors monitoring fungicides, due to their broadly usage and their adverse effects on humans and wildlife. In the present study, a colorimetric probe has been proposed for detection of prothioconazole based on aggregation of unmodified silver nanoparticles (AgNPs). Under optimized condition, linear relationships between the concentration of prothioconazole and the absorbance ratio of A500/A395 were found over the range of 0.01 μg·mL- 1 to 0.4 μg·mL- 1 with quantification limit as low as 1.7 ng·mL- 1. Furthermore, AgNPs color change from yellow to pink-orange in presence of prothioconazole, indicates highly sensitive naked-eye colorimetric assay for quantifying prothioconazole in real applications. The proposed approach was successfully used for the determination of prothioconazole in wheat flour and paddy water sample.

  1. Characterization of the biodegradation, bioremediation and detoxification capacity of a bacterial consortium able to degrade the fungicide thiabendazole.

    Science.gov (United States)

    Perruchon, Chiara; Pantoleon, Anastasios; Veroutis, Dimitrios; Gallego-Blanco, Sara; Martin-Laurent, F; Liadaki, Kalliopi; Karpouzas, Dimitrios G

    2017-12-01

    Thiabendazole (TBZ) is a persistent fungicide used in the post-harvest treatment of fruits. Its application results in the production of contaminated effluents which should be treated before their environmental discharge. In the absence of efficient treatment methods in place, biological systems based on microbial inocula with specialized degrading capacities against TBZ could be a feasible treatment approach. Only recently the first bacterial consortium able to rapidly transform TBZ was isolated. This study aimed to characterize its biodegradation, bioremediation and detoxification potential. The capacity of the consortium to mineralize 14 C-benzyl-ring labelled TBZ was initially assessed. Subsequent tests evaluated its degradation capacity under various conditions (range of pH, temperatures and TBZ concentration levels) and relevant practical scenarios (simultaneous presence of other postharvest compounds) and its bioaugmentation potential in soils contaminated with increasing TBZ levels. Finally cytotoxicity assays explored its detoxification potential. The consortium effectively mineralized the benzoyl ring of the benzimidazole moiety of TBZ and degraded spillage level concentrations of the fungicide in aqueous cultures (750 mg L -1 ) and in soil (500 mg kg -1 ). It maintained its high degradation capacity in a wide range of pH (4.5-7.5) and temperatures (15-37 °C) and in the presence of other pesticides (ortho-phenylphenol and diphenylamine). Toxicity assays using the human liver cancer cell line HepG2 showed a progressive decrease in cytotoxicity, concomitantly with the biodegradation of TBZ, pointing to a detoxification process. Overall, the bacterial consortium showed high potential for future implementation in bioremediation and biodepuration applications.

  2. Direct and indirect toxicity of the fungicide pyraclostrobin to Hyalella azteca and effects on leaf processing under realistic daily temperature regimes.

    Science.gov (United States)

    Willming, Morgan M; Maul, Jonathan D

    2016-04-01

    Fungicides in aquatic environments can impact non-target bacterial and fungal communities and the invertebrate detritivores responsible for the decomposition of allochthonous organic matter. Additionally, in some aquatic systems daily water temperature fluctuations may influence these processes and alter contaminant toxicity, but such temperature fluctuations are rarely examined in conjunction with contaminants. In this study, the shredding amphipod Hyalella azteca was exposed to the fungicide pyraclostrobin in three experiments. Endpoints included mortality, organism growth, and leaf processing. One experiment was conducted at a constant temperature (23 °C), a fluctuating temperature regime (18-25 °C) based on field-collected data from the S. Llano River, Texas, or an adjusted fluctuating temperature regime (20-26 °C) based on possible climate change predictions. Pyraclostrobin significantly reduced leaf shredding and increased H. azteca mortality at concentrations of 40 μg/L or greater at a constant 23 °C and decreased leaf shredding at concentrations of 15 μg/L or greater in the fluctuating temperatures. There was a significant interaction between temperature treatment and pyraclostrobin concentration on H. azteca mortality, body length, and dry mass under direct aqueous exposure conditions. In an indirect exposure scenario in which only leaf material was exposed to pyraclostrobin, H. azteca did not preferentially feed on or avoid treated leaf disks compared to controls. This study describes the influence of realistic temperature variation on fungicide toxicity to shredding invertebrates, which is important for understanding how future alterations in daily temperature regimes due to climate change may influence the assessment of ecological risk of contaminants in aquatic ecosystems. Copyright © 2016. Published by Elsevier Ltd.

  3. Effects of the fungicide metiram in outdoor freshwater microcosms: responses of invertebrates, primary producers and microbes.

    Science.gov (United States)

    Lin, Ronghua; Buijse, Laura; Dimitrov, Mauricio R; Dohmen, Peter; Kosol, Sujitra; Maltby, Lorraine; Roessink, Ivo; Sinkeldam, Jos A; Smidt, Hauke; Van Wijngaarden, René P A; Brock, Theo C M

    2012-07-01

    The ecological impact of the dithiocarbamate fungicide metiram was studied in outdoor freshwater microcosms, consisting of 14 enclosures placed in an experimental ditch. The microcosms were treated three times (interval 7 days) with the formulated product BAS 222 28F (Polyram®). Intended metiram concentrations in the overlying water were 0, 4, 12, 36, 108 and 324 μg a.i./L. Responses of zooplankton, macroinvertebrates, phytoplankton, macrophytes, microbes and community metabolism endpoints were investigated. Dissipation half-life (DT₅₀) of metiram was approximately 1-6 h in the water column of the microcosm test system and the metabolites formed were not persistent. Multivariate analysis indicated treatment-related effects on the zooplankton (NOEC(community) = 36 μg a.i./L). Consistent treatment-related effects on the phytoplankton and macroinvertebrate communities and on the sediment microbial community could not be demonstrated or were minor. There was no evidence that metiram affected the biomass, abundance or functioning of aquatic hyphomycetes on decomposing alder leaves. The most sensitive populations in the microcosms comprised representatives of Rotifera with a NOEC of 12 μg a.i./L on isolated sampling days and a NOEC of 36 μg a.i./L on consecutive samplings. At the highest treatment-level populations of Copepoda (zooplankton) and the blue-green alga Anabaena (phytoplankton) also showed a short-term decline on consecutive sampling days (NOEC = 108 μg a.i./L). Indirect effects in the form of short-term increases in the abundance of a few macroinvertebrate and several phytoplankton taxa were also observed. The overall community and population level no-observed-effect concentration (NOEC(microcosm)) was 12-36 μg a.i./L. At higher treatment levels, including the test systems that received the highest dose, ecological recovery of affected measurement endpoints was fast (effect period < 8 weeks).

  4. Development of a novel multiplex DNA microarray for Fusarium graminearum and analysis of azole fungicide responses

    Directory of Open Access Journals (Sweden)

    Deising Holger B

    2011-01-01

    Full Text Available Abstract Background The toxigenic fungal plant pathogen Fusarium graminearum compromises wheat production worldwide. Azole fungicides play a prominent role in controlling this pathogen. Sequencing of its genome stimulated the development of high-throughput technologies to study mechanisms of coping with fungicide stress and adaptation to fungicides at a previously unprecedented precision. DNA-microarrays have been used to analyze genome-wide gene expression patterns and uncovered complex transcriptional responses. A recently developed one-color multiplex array format allowed flexible, effective, and parallel examinations of eight RNA samples. Results We took advantage of the 8 × 15 k Agilent format to design, evaluate, and apply a novel microarray covering the whole F. graminearum genome to analyze transcriptional responses to azole fungicide treatment. Comparative statistical analysis of expression profiles uncovered 1058 genes that were significantly differentially expressed after azole-treatment. Quantitative RT-PCR analysis for 31 selected genes indicated high conformity to results from the microarray hybridization. Among the 596 genes with significantly increased transcript levels, analyses using GeneOntology and FunCat annotations detected the ergosterol-biosynthesis pathway genes as the category most significantly responding, confirming the mode-of-action of azole fungicides. Cyp51A, which is one of the three F. graminearum paralogs of Cyp51 encoding the target of azoles, was the most consistently differentially expressed gene of the entire study. A molecular phylogeny analyzing the relationships of the three CYP51 proteins in the context of 38 fungal genomes belonging to the Pezizomycotina indicated that CYP51C (FGSG_11024 groups with a new clade of CYP51 proteins. The transcriptional profiles for genes encoding ABC transporters and transcription factors suggested several involved in mechanisms alleviating the impact of the fungicide

  5. Effect of fungicide on Fusarium verticillioidesmycelial morphology and fumonisin B1 production

    Directory of Open Access Journals (Sweden)

    Tatiana de Á. Miguel

    2015-03-01

    Full Text Available The effect of fludioxonil + metalaxyl-M on the mycelial morphology, sporulation and fumonisin B1 production by Fusarium verticillioides 103 F was evaluated. Scanning electron microscopy analysis showed that the fungicide caused inhibition of hyphal growth and defects on hyphae morphology such as cell wall disruption, withered hyphae, and excessive septation. In addition, extracellular material around the hyphae was rarely observed in the presence of fludioxonil + metalaxyl-M. While promoting the reduction of mycelial growth, the fungicide increased sporulation of F. verticillioides compared to the control, and the highest production occurred on the 14th day in the treatments and on the 10th day in the control cultures. Fumonisin B1production in the culture media containing the fungicide (treatment was detected from the 7th day incubation, whereas in cultures without fungicide (control it was detected on the 10th day. The highest fumonisin B1 production occurred on the 14th day, both for the control and for the treatment. Fludioxonil + metalaxyl - M can interfere in F. verticillioides mycelial morphology and sporulation and increase fumonisin B1 levels. These data indicate the importance of understanding the effects of fungicide to minimize the occurrence of toxigenic fungi and fumonisins.

  6. Effect of fungicide on Fusarium verticillioides mycelial morphology and fumonisin B₁ production.

    Science.gov (United States)

    Miguel, Tatiana de Á; Bordini, Jaqueline G; Saito, Gervásio H; Andrade, Célia G T de J; Ono, Mario A; Hirooka, Elisa Y; Vizoni, Édio; Ono, Elisabete Y S

    2015-03-01

    The effect of fludioxonil + metalaxyl-M on the mycelial morphology, sporulation and fumonisin B 1 production by Fusarium verticillioides 103 F was evaluated. Scanning electron microscopy analysis showed that the fungicide caused inhibition of hyphal growth and defects on hyphae morphology such as cell wall disruption, withered hyphae, and excessive septation. In addition, extracellular material around the hyphae was rarely observed in the presence of fludioxonil + metalaxyl-M. While promoting the reduction of mycelial growth, the fungicide increased sporulation of F. verticillioides compared to the control, and the highest production occurred on the 14 (th) day in the treatments and on the 10 (th) day in the control cultures. Fumonisin B 1 production in the culture media containing the fungicide (treatment) was detected from the 7 (th) day incubation, whereas in cultures without fungicide (control) it was detected on the 10 (th) day. The highest fumonisin B 1 production occurred on the 14 (th) day, both for the control and for the treatment. Fludioxonil + metalaxyl - M can interfere in F. verticillioides mycelial morphology and sporulation and increase fumonisin B 1 levels. These data indicate the importance of understanding the effects of fungicide to minimize the occurrence of toxigenic fungi and fumonisins.

  7. Effect of fungicide on Fusarium verticillioides mycelial morphology and fumonisin B 1 production

    Science.gov (United States)

    Miguel, Tatiana de Á.; Bordini, Jaqueline G.; Saito, Gervásio H.; Andrade, Célia G.T. de J.; Ono, Mario A.; Hirooka, Elisa Y.; Vizoni, Édio; Ono, Elisabete Y.S.

    2015-01-01

    The effect of fludioxonil + metalaxyl-M on the mycelial morphology, sporulation and fumonisin B 1 production by Fusarium verticillioides 103 F was evaluated. Scanning electron microscopy analysis showed that the fungicide caused inhibition of hyphal growth and defects on hyphae morphology such as cell wall disruption, withered hyphae, and excessive septation. In addition, extracellular material around the hyphae was rarely observed in the presence of fludioxonil + metalaxyl-M. While promoting the reduction of mycelial growth, the fungicide increased sporulation of F. verticillioides compared to the control, and the highest production occurred on the 14 th day in the treatments and on the 10 th day in the control cultures. Fumonisin B 1 production in the culture media containing the fungicide (treatment) was detected from the 7 th day incubation, whereas in cultures without fungicide (control) it was detected on the 10 th day. The highest fumonisin B 1 production occurred on the 14 th day, both for the control and for the treatment. Fludioxonil + metalaxyl - M can interfere in F. verticillioides mycelial morphology and sporulation and increase fumonisin B 1 levels. These data indicate the importance of understanding the effects of fungicide to minimize the occurrence of toxigenic fungi and fumonisins. PMID:26221120

  8. Sensitivity of some nitrogen fixers and the target pest Fusarium oxysporum to fungicide thiram.

    Science.gov (United States)

    Osman, Awad G; Sherif, Ashraf M; Elhussein, Adil A; Mohamed, Afrah T

    2012-03-01

    This study was carried out to investigate the toxic effects of the fungicide thiram (TMTD) against five nitrogen fixers and the thiram target pest Fusarium oxysporum under laboratory conditions. Nitrogen fixing bacteria Falvobacterium showed the highest values of LD(50) and proved to be the most resistant to the fungicide followed by Fusarium oxysporum, while Pseudomonas aurentiaca was the most affected microorganism. LD(50) values for these microorganisms were in 2-5 orders of magnitude lower in comparison with LD(50) value for Fusarium oxysporum. Thiram was most toxic to Pseudomonas aurentiaca followed by Azospirillum. The lowest toxicity index was recorded for Fusarium oxysporum and Flavobacterium. The slope of the curve for Azomonas, Fusarium oxysporum and Flavobacterium is more steep than that of the other curves, suggesting that even a slight increase of the dose of the fungicide can cause a very strong negative effect. Thiram was more selective to Pseudomonas aurentiaca followed by Azospirillum, Rhizobium meliloti and Azomonas. The lowest selectivity index of the fungicide was recorded for Falvobacterium followed by Fusarium oxysporum. The highest safety coefficient of the fungicide was assigned for Flavobacterium, while Pseudomonas aurentiaca showed the lowest value.

  9. Post-infection activities of fungicides against Cercospora arachidicola of peanut (Arachis hypogaea).

    Science.gov (United States)

    Johnson, Robert C; Cantonwine, Emily G

    2014-08-01

    Despite strong indirect evidence of post-infection activity by a selection of systemic fungicides against Cercospora arachidicola, the causal organism of early leaf spot of peanut, direct post-infection activities in this pathosystem have yet to be reported in detail. This study was conducted to describe the activities of pyraclostrobin, penthiopyrad and prothioconazole on early leaf spot when each fungicide was applied after pathogen penetration began and throughout the incubation period. Most C. arachidicola penetration events occurred between 3 and 5 days after inoculation (dai), and the mean incubation period was 11.8 dai. Post-infection activities of the systemic fungicides were similar for all dependent variables measured. Systemic fungicides reduced lesion density compared with the non-treated control when applied at 3, 5 and 7 dai, and disease severity was >60% less for leaves treated with a systemic fungicide at all application dates (3, 5, 7, 9, 11 and 13 dai). Pyraclostrobin, penthiopyrad and prothioconazole showed similar systemic mobility within peanut leaves and activities against C. arachidicola, and appear to completely arrest the development of the pathogen at least 2 days post penetration, and limit pathogen colonization even when applications occur after symptom onset. © 2013 Society of Chemical Industry.

  10. Differences Among Commonly Sprayed Orchard Fungicides in Targeting the Beneficial Fungi Associated with Honey Bee Colony and Bee Bread Provisions (In Vitro)

    Science.gov (United States)

    Our studies evaluated the effects of representative fungicides, boscalid and pyraclostrobin, propiconazole, and chlorothalonil, alone and in combination, on 12 fungi species isolated from bee bread. Chlorothalonil was fungicidal (slowed growth without killing) and was least effective on Aspergillus...

  11. Direct and indirect toxicity of the fungicide pyraclostrobin to Hyalella azteca and effects on leaf processing under realistic daily temperature regimes

    International Nuclear Information System (INIS)

    Willming, Morgan M.; Maul, Jonathan D.

    2016-01-01

    Fungicides in aquatic environments can impact non-target bacterial and fungal communities and the invertebrate detritivores responsible for the decomposition of allochthonous organic matter. Additionally, in some aquatic systems daily water temperature fluctuations may influence these processes and alter contaminant toxicity, but such temperature fluctuations are rarely examined in conjunction with contaminants. In this study, the shredding amphipod Hyalella azteca was exposed to the fungicide pyraclostrobin in three experiments. Endpoints included mortality, organism growth, and leaf processing. One experiment was conducted at a constant temperature (23 °C), a fluctuating temperature regime (18–25 °C) based on field-collected data from the S. Llano River, Texas, or an adjusted fluctuating temperature regime (20–26 °C) based on possible climate change predictions. Pyraclostrobin significantly reduced leaf shredding and increased H. azteca mortality at concentrations of 40 μg/L or greater at a constant 23 °C and decreased leaf shredding at concentrations of 15 μg/L or greater in the fluctuating temperatures. There was a significant interaction between temperature treatment and pyraclostrobin concentration on H. azteca mortality, body length, and dry mass under direct aqueous exposure conditions. In an indirect exposure scenario in which only leaf material was exposed to pyraclostrobin, H. azteca did not preferentially feed on or avoid treated leaf disks compared to controls. This study describes the influence of realistic temperature variation on fungicide toxicity to shredding invertebrates, which is important for understanding how future alterations in daily temperature regimes due to climate change may influence the assessment of ecological risk of contaminants in aquatic ecosystems. - Highlights: • Pyraclostrobin was directly toxic to Hyalella azteca and reduced leaf processing. • Indirect exposure via leaf material did not change H

  12. Phytotoxicity of the combination of some insecticides and fungicides on the ornamental species Petunia sp.

    Directory of Open Access Journals (Sweden)

    Renata Bažok

    2016-12-01

    Full Text Available In the production of ornamental plants, it is often necessary to combine plant protection products (PPPs for simultaneous pest control. The use of a combination of PPPs often leads to phytotoxicity. The aim of this study was to determine the phytotoxicity of the combination of fungicides (azoxystrobin and cyprodinil + fludioxonil and insecticides based on abamectin and thiomethoxam on the ornamental plant Petunia sp. The PPPs are used at recommended and double doses. Based on the damage, phytotoxicity indices were calculated. Petunia plants are sensitive even when PPPs are used in recommended doses. Combinations of the both insecticides with the combined fungicide based on cyprodinil and fludioxinil can be advised to protect petunias only if one applies the recommended doses. All combinations of insecticides with a fungicide based on azoxystrobin should not be applied because there is a serious risk of phytotoxicity.

  13. Fungicidal effect of 15 disinfectants against 25 fungal contaminants commonly found in bread and cheese manufacturing.

    Science.gov (United States)

    Bundgaard-Nielsen, K; Nielsen, P V

    1996-03-01

    Resistance of 19 mold and 6 yeast species to 15 commercial disinfectants was investigated by using a suspension method in which the fungicidal effect and germination time were determined at 20 degrees C. Disinfectants containing 0.5% dodecyldiethylentriaminacetic acid, 10 g of chloramine-T per 1, 2.0% formaldehyde, 0.1% potassium hydroxide, 3.0% hydrogen peroxide, or 0.3% peracetic acid were ineffective as fungicides. The fungicidal effect of quaternary ammonium compounds and chlorine compounds showed great variability between species and among the six isolates of Penicillium roqueforti var. roqueforti tested. The isolates of P roqueforti var. carneum, P. discolor, Aspergillus versicolor, and Eurotium repens examined were resistant to different quaternary ammonium compounds. Conidia and vegetative cells were killed by alcohols, whereas ascospores were resistant. Resistance of ascospores to 70% ethanol increased with age. Both P. roqueforti var. roqueforti and E. repens showed great variability of resistance within isolates of each species.

  14. Estimation of sorption coefficients for fungicides in soil and turfgrass thatch

    Energy Technology Data Exchange (ETDEWEB)

    Dell, C.J.; Throssell, C.S.; Bischoff, M. [Purdue Univ., West Lafayette, IN (United States)] [and others

    1994-01-01

    Environmental fates of turf-applied fungicides are not well understood. The role of thatch as a sorptive surface for fungicides has not been evaluated. Thatch may decrease mobility of fungi and decrease their potential to be transported off-site. Batch type sorption studies were conducted to determine sorption coefficients (K{sub f}) for the fungicides triadimefon, [1-(4-chlorophenoxy)-3,3-dimethyl 1-1(1H-1,2,4- triazol-l-g-l) butanone], vinclozolin [3-(3,5-dichlorophenyl)-5-methyl- 5-vinyl-1,3-oxazolidine-2,4-dione], and chloroneb (1,4-dichloro-2,5-dimethoxybenzone) in thatch and in the underlying soil.

  15. Thiamine primed defense provides reliable alternative to systemic fungicide carbendazim against sheath blight disease in rice (Oryza sativa L.).

    Science.gov (United States)

    Bahuguna, Rajeev Nayan; Joshi, Rohit; Shukla, Alok; Pandey, Mayank; Kumar, J

    2012-08-01

    A novel pathogen defense strategy by thiamine priming was evaluated for its efficacy against sheath blight pathogen, Rhizoctonia solani AG-1A, of rice and compared with that of systemic fungicide, carbendazim (BCM). Seeds of semidwarf, high yielding, basmati rice variety Vasumati were treated with thiamine (50 mM) and BCM (4 mM). The pot cultured plants were challenge inoculated with R. solani after 40 days of sowing and effect of thiamine and BCM on rice growth and yield traits was examined. Higher hydrogen peroxide content, total phenolics accumulation, phenylalanine ammonia lyase (PAL) activity and superoxide dismutase (SOD) activity under thiamine treatment displayed elevated level of systemic resistance, which was further augmented under challenging pathogen infection. High transcript level of phenylalanine ammonia lyase (PAL) and manganese superoxide dismutase (MnSOD) validated mode of thiamine primed defense. Though minimum disease severity was observed under BCM treatment, thiamine produced comparable results, with 18.12 per cent lower efficacy. Along with fortifying defense components and minor influence on photosynthetic pigments and nitrate reductase (NR) activity, thiamine treatment significantly reduced pathogen-induced loss in photosynthesis, stomatal conductance, chlorophyll fluorescence, NR activity and NR transcript level. Physiological traits affected under pathogen infection were found signatory for characterizing plant's response under disease and were detectable at early stage of infection. These findings provide a novel paradigm for developing alternative, environmentally safe strategies to control plant diseases. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  16. The Mancozeb-containing carbamate fungicide tattoo induces mild oxidative stress in goldfish brain, liver, and kidney.

    Science.gov (United States)

    Atamaniuk, Tetiana M; Kubrak, Olga I; Husak, Viktor V; Storey, Kenneth B; Lushchak, Volodymyr I

    2014-11-01

    Tattoo belongs to the group of carbamate fungicides and contains Mancozeb (ethylene(bis)dithiocarbamate) as its main constituent. The toxicity of Mancozeb to living organisms, particularly fish, is not resolved. This work investigated the effects of 96 h of exposure to 3, 5, or 10 mg L(-1) of Tattoo (corresponding to 0.9, 1.5, or 3 mg L(-1) of Mancozeb) on the levels of oxidative stress markers and the antioxidant enzyme system of brain, liver, and kidney of goldfish, Carassius auratus). In liver, Tattoo exposure resulted in increased activities of superoxide dismutase (SOD) by 70%-79%, catalase by 23%-52% and glutathione peroxidase (GPx) by 49%. The content of protein carbonyls (CP) in liver was also enhanced by 92%-125% indicating extensive damage to proteins. Similar increases in CP levels (by 98%-111%) accompanied by reduced glucose-6-phosphate dehydrogenase activity (by 13%-15%) was observed in kidney of fish exposed to Tattoo; however, SOD activity increased by 37% in this tissue after treatment with 10 mg L(-1) Tattoo. In brain, a rise in lipid peroxide level (by 29%) took place after exposure to 10 mg L(-1) Tattoo and was accompanied by elevation of high-molecular mass thiols (by 14%). Tattoo exposure also resulted in a concentration-dependent decrease in glutathione reductase activity (by 26%-37%) in brain. The data collectively show that exposure of goldfish to 3-10 mg L(-1) of the carbamate fungicide Tattoo resulted in the development of mild oxidative stress and activation of antioxidant defense systems in goldfish tissues. Copyright © 2013 Wiley Periodicals, Inc., a Wiley company.

  17. Laboratory bioassays to estimate the lethal and sublethal effects of various insecticides and fungicides on Deraeocoris brevis (Hemiptera: Miridae).

    Science.gov (United States)

    Amarasekare, K G; Shearer, P W

    2013-04-01

    This laboratory bioassay focused on lethal and sublethal effects of five insecticides (chlorantraniliprole, cyantraniliprole, spinetoram, novaluron, and lambda-cyhalothrin) and two fungicide treatments (sulfur and a mixture of copper hydroxide and mancozeb) on the predatory mired bug, Deraeocoris brevis (Uhler) (Hemiptera: Miridae) using second instars and adult males and females. Formulated pesticides were tested using concentrations that were equivalent to the high label rate (1x) (high rate) and 1/10th of that amount (0.1x) (low rate) dissolved in 378.5 liters of water. Lambda-cyhalothrin was highly toxic to D. brevis nymphs and adults at both rates, whereas both rates of novaluron were highly toxic to nymphs. Cyantraniliprole, chlorantraniliprole, and novaluron were less toxic to adults, and chlorantraniliprole and spinetoram were less toxic to nymphs. Both rates of spinetoram caused significant mortality to adults. Fecundity of adult females was affected negatively by the high rates of either novaluron or spinetoram, whereas the fertility was affected only by the high rate of novaluron. The high rate of spinetoram reduced survival of nymphs. Adults treated with spinetoram had reduced longevity. Cyantraniliprole caused some mortality to nymphs and affected their survival. Both rates of sulfur were toxic to nymphs and affected emergence to adults. The mixture of copper hydroxide and mancozeb was less toxic to D. brevis. Neither adult longevity nor sex ratio was affected by the fungicides. The r values for D. brecis treated with lambda-cyhalothrin, novaluron, spinetoram, and sulfur were low, indicating that these products may have negative impact on population growth.

  18. Combinations of fungicide and cultural practices influence the incidence and impact of fusiform rust in slash pine plantations

    Science.gov (United States)

    James D. Haywood; Allan E. Tiarks

    1994-01-01

    Slash pine was grown in central Louisiana under four levels of culture with or without repeated sprayings of the systematic fungicide triadimefon for protection against fusiform rust. The eight treatment combinations were: (1)no fungicide, weed control, or fertilizer; (2)weeded; (3)weeded, applied inorganic fertilizer, and bedded before planting; (4)weeded, bedded,...

  19. Phytopharmacology of the rice diseases. I. In vitro tests on application of the dust fungicides to the important pathogenic fungi

    Energy Technology Data Exchange (ETDEWEB)

    Hashioka, Y; Saito, T

    1953-01-01

    In this paper, the results of experiments on the repressing effect of selected fungicides on the growth of pathogenic fungi of rice are reported. Organic mercury compounds were tested and found to be more effective fungicides than copper. Their use in agriculture is recommended.

  20. Rainfall thresholds as support for timing fungicide applications in the control of potato late blight in Ecuador and Peru

    DEFF Research Database (Denmark)

    Kromann, Peter; Taipe, Arturo; Perez, Willmer G.

    2009-01-01

    Accumulated rainfall thresholds were studied in seven field experiments conducted in Ecuador and Peru for their value in timing applications of fungicide to control potato late blight, caused by Phytophthora infestans. Fungicide regimes based on accumulated rainfall thresholds ranging from 10 to 70...

  1. 48 CFR 1552.235-73 - Access to Federal Insecticide, Fungicide, and Rodenticide Act Confidential Business Information...

    Science.gov (United States)

    2010-10-01

    ... Insecticide, Fungicide, and Rodenticide Act Confidential Business Information (APR 1996). 1552.235-73 Section... Insecticide, Fungicide, and Rodenticide Act Confidential Business Information (APR 1996). As prescribed in... Act Confidential Business Information (APR 1996) In order to perform duties under the contract, the...

  2. The Synergistic Effects of Almond Protection Fungicides on Honey Bee (Hymenoptera: Apidae) Forager Survival.

    Science.gov (United States)

    Fisher, Adrian; Coleman, Chet; Hoffmann, Clint; Fritz, Brad; Rangel, Juliana

    2017-06-01

    The honey bee (Apis mellifera L.) contributes ∼$17 billion annually to the United States economy, primarily by pollinating major agricultural crops including almond, which is completely dependent on honey bee pollination for nut set. Almond growers face constant challenges to crop productivity owing to pests and pathogens, which are often controlled with a multitude of agrochemicals. For example, fungicides are often applied in combination with other products to control fungal pathogens during almond bloom. However, the effects of fungicides on honey bee health have been so far understudied. To assess the effects of some of the top fungicides used during the 2012 California almond bloom on honey bee forager mortality, we collected foragers from a local apiary and exposed them to fungicides (alone and in various combinations) at the label dose, or at doses ranging from 0.25 to 2 times the label dose rate. These fungicides were Iprodione 2SE Select, Pristine, and Quadris. We utilized a wind tunnel and atomizer set up with a wind speed of 2.9 m/s to simulate field-relevant exposure of honey bees to these agrochemicals during aerial application in almond fields. Groups of 40-50 foragers exposed to either untreated controls or fungicide-laden treatments were monitored daily over a 10-d period. Our results showed a significant decrease in forager survival resulting from exposure to simulated tank mixes of Iprodione 2SE Select, as well as synergistic detrimental effects of Iprodione 2SE Select in combination with Pristine and Quadris on forager survival. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Effect of Maize Hybrid and Foliar Fungicides on Yield Under Low Foliar Disease Severity Conditions.

    Science.gov (United States)

    Mallowa, Sally O; Esker, Paul D; Paul, Pierce A; Bradley, Carl A; Chapara, Venkata R; Conley, Shawn P; Robertson, Alison E

    2015-08-01

    Foliar fungicide use in the U.S. Corn Belt increased in the last decade; however, questions persist pertaining to its value and sustainability. Multistate field trials were established from 2010 to 2012 in Illinois, Iowa, Ohio, and Wisconsin to examine how hybrid and foliar fungicide influenced disease intensity and yield. The experimental design was in a split-split plot with main plots consisting of hybrids varying in resistance to gray leaf spot (caused by Cercospora zeae-maydis) and northern corn leaf blight (caused by Setosphaera turcica), subplots corresponding to four application timings of the fungicide pyraclostrobin, and sub-subplots represented by inoculations with either C. zeae-maydis, S. turcica, or both at two vegetative growth stages. Fungicide application (VT/R1) significantly reduced total disease severity relative to the control in five of eight site-years (P<0.05). Disease was reduced by approximately 30% at Wisconsin in 2011, 20% at Illinois in 2010, 29% at Iowa in 2010, and 32 and 30% at Ohio in 2010 and 2012, respectively. These disease severities ranged from 0.2 to 0.3% in Wisconsin in 2011 to 16.7 to 22.1% in Illinois in 2010. The untreated control had significantly lower yield (P<0.05) than the fungicide-treated in three site-years. Fungicide application increased the yield by approximately 6% at Ohio in 2010, 5% at Wisconsin in 2010 and 6% in 2011. Yield differences ranged from 8,403 to 8,890 kg/ha in Wisconsin 2011 to 11,362 to 11,919 kg/ha in Wisconsin 2010. Results suggest susceptibility to disease and prevailing environment are important drivers of observed differences. Yield increases as a result of the physiological benefits of plant health benefits under low disease were not consistent.

  4. Using Epidemiological Principles to Explain Fungicide Resistance Management Tactics: Why do Mixtures Outperform Alternations?

    Science.gov (United States)

    Elderfield, James A D; Lopez-Ruiz, Francisco J; van den Bosch, Frank; Cunniffe, Nik J

    2018-07-01

    Whether fungicide resistance management is optimized by spraying chemicals with different modes of action as a mixture (i.e., simultaneously) or in alternation (i.e., sequentially) has been studied by experimenters and modelers for decades. However, results have been inconclusive. We use previously parameterized and validated mathematical models of wheat Septoria leaf blotch and grapevine powdery mildew to test which tactic provides better resistance management, using the total yield before resistance causes disease control to become economically ineffective ("lifetime yield") to measure effectiveness. We focus on tactics involving the combination of a low-risk and a high-risk fungicide, and the case in which resistance to the high-risk chemical is complete (i.e., in which there is no partial resistance). Lifetime yield is then optimized by spraying as much low-risk fungicide as is permitted, combined with slightly more high-risk fungicide than needed for acceptable initial disease control, applying these fungicides as a mixture. That mixture rather than alternation gives better performance is invariant to model parameterization and structure, as well as the pathosystem in question. However, if comparison focuses on other metrics, e.g., lifetime yield at full label dose, either mixture or alternation can be optimal. Our work shows how epidemiological principles can explain the evolution of fungicide resistance, and also highlights a theoretical framework to address the question of whether mixture or alternation provides better resistance management. It also demonstrates that precisely how spray tactics are compared must be given careful consideration. [Formula: see text] Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

  5. Sequential extraction and availability of copper in Cu fungicide-amended vineyard soils from Southern Brazil

    International Nuclear Information System (INIS)

    Correa Nogueirol, Roberta; Ferracciu Alleoni, Luis Reynaldo; Ribeiro Nachtigall, Gilmar; Wellington de Melo, George

    2010-01-01

    The continuous use of cupric fungicides in vineyards, mainly copper sulfate (as a component of the bordeaux mixture), has increased Cu concentration in soils to levels near or even above the maximum established by the Commission of Soil Chemistry and Fertility of the States of Santa Catarina and Rio Grande do Sul, Brazil. Besides the total content, the fractions of the element along the soil profile must be known, because the total content of Cu in the soil is not sufficient to express its environmental impact. The objective of this study was to evaluate the variation of Cu contentes along the soil profile and its speciation and partitioning in 29 soil samples from vineyards in the state of Rio Grande do Sul, Brazil. Samples were collected in areas cropped with vineyards older than 15 years that had been frequently treated with the bordeaux mixture. These samples were from Nitosols, Acrisols, Cambisols and Leptosols and were analysed by sequential extractions and several chemical extractors. Soils had diverse chemical and physical attributes: clay content in the plowed layer (0-0.2 m) ranged from 120 to 610 g kg -1 , pH ranged from 5.3 to 7.3 and organic carbon contents varied from 2.9 to 51 g dm -3 . Among the 29 samples, 16 had the total Cu above the maximum limit allowed by the European Community regulations (140 mg kg -1 ). The average amount of Cu bonded to the oxide fraction accounted for 49.5% of the total Cu.

  6. Sequential extraction and availability of copper in Cu fungicide-amended vineyard soils from Southern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Correa Nogueirol, Roberta [University of Sao Paulo (ESALQ/USP), C.P. 9, Piracicaba 13418-900, SP (Brazil); Ferracciu Alleoni, Luis Reynaldo, E-mail: alleoni@esalq.usp.br [Department of Soil Science, ESALQ/USP. C.P. 9, Piracicaba 13418-900, SP (Brazil); Ribeiro Nachtigall, Gilmar; Wellington de Melo, George [National Research Center of Grapes and Wine - Embrapa Uva e Vinho, C.P. 130, Bento Goncalves 95700-000, RS (Brazil)

    2010-09-15

    The continuous use of cupric fungicides in vineyards, mainly copper sulfate (as a component of the bordeaux mixture), has increased Cu concentration in soils to levels near or even above the maximum established by the Commission of Soil Chemistry and Fertility of the States of Santa Catarina and Rio Grande do Sul, Brazil. Besides the total content, the fractions of the element along the soil profile must be known, because the total content of Cu in the soil is not sufficient to express its environmental impact. The objective of this study was to evaluate the variation of Cu contentes along the soil profile and its speciation and partitioning in 29 soil samples from vineyards in the state of Rio Grande do Sul, Brazil. Samples were collected in areas cropped with vineyards older than 15 years that had been frequently treated with the bordeaux mixture. These samples were from Nitosols, Acrisols, Cambisols and Leptosols and were analysed by sequential extractions and several chemical extractors. Soils had diverse chemical and physical attributes: clay content in the plowed layer (0-0.2 m) ranged from 120 to 610 g kg{sup -1}, pH ranged from 5.3 to 7.3 and organic carbon contents varied from 2.9 to 51 g dm{sup -3}. Among the 29 samples, 16 had the total Cu above the maximum limit allowed by the European Community regulations (140 mg kg{sup -1}). The average amount of Cu bonded to the oxide fraction accounted for 49.5% of the total Cu.

  7. The effect of the Falcon 460 EC fungicide on soil microbial communities, enzyme activities and plant growth.

    Science.gov (United States)

    Baćmaga, Małgorzata; Wyszkowska, Jadwiga; Kucharski, Jan

    2016-10-01

    Fungicides are considered to be effective crop protection chemicals in modern agriculture. However, they can also exert toxic effects on non-target organisms, including soil-dwelling microbes. Therefore, the environmental fate of fungicides has to be closely monitored. The aim of this study was to evaluate the influence of the Falcon 460 EC fungicide on microbial diversity, enzyme activity and resistance, and plant growth. Samples of sandy loam with pH KCl 7.0 were collected for laboratory analyses on experimental days 30, 60 and 90. Falcon 460 EC was applied to soil in the following doses: control (soil without the fungicide), dose recommended by the manufacturer, 30-fold higher than the recommended dose, 150-fold higher than the recommended dose and 300-fold higher than the recommended dose. The observed differences in the values of the colony development index and the eco-physiological index indicate that the mixture of spiroxamine, tebuconazole and triadimenol modified the biological diversity of the analyzed groups of soil microorganisms. Bacteria of the genus Bacillus and fungi of the genera Penicillium and Rhizopus were isolated from fungicide-contaminated soil. The tested fungicide inhibited the activity of dehydrogenases, catalase, urease, acid phosphatase and alkaline phosphatase. The greatest changes were induced by the highest fungicide dose 300-fold higher than the recommended dose. Dehydrogenases were most resistant to soil contamination. The Phytotoxkit test revealed that the analyzed fungicide inhibits seed germination capacity and root elongation. The results of this study indicate that excessive doses of the Falcon 460 EC fungicide 30-fold higher than the recommended dose to 300-fold higher than the recommended dose) can induce changes in the biological activity of soil. The analyzed microbiological and biochemical parameters are reliable indicators of the fungicide's toxic effects on soil quality.

  8. EFFECTS DISTRIBUTIVE THE WAGE MINIMUM IN MARKET OF LABOR CEARENSE

    Directory of Open Access Journals (Sweden)

    Joyciane Coelho Vasconcelos

    2015-11-01

    Full Text Available This paper analyses the contribution of the minimum wage (MW for the devolution of income from the labor market at Ceará in the period 2002-2012. This research was based on National Sample Survey (PNAD of the Brazilian Institute of Geography and Statistics (IBGE.It was used the simulation methodology proposed in DiNardo, Fortin and Lemieux (1996 from the estimated counterfactual Kernel density functions. The simulations were performed for females and males. The results revealed by the decompositions than the minimum wage, the degree of formalization and the personal attributes had impacts not concentrators to workers female and male. However, for women, the de-concentrating effect of the minimum wage is more intense in the sample compared to men. In summary, the simulations indicate the importance of the minimum wage to reduce the dispersion of labor income in recent years.

  9. Assessment of strobilurin fungicides' content in soya-based drinks by liquid micro-extraction and liquid chromatography with tandem mass spectrometry.

    Science.gov (United States)

    Campillo, Natalia; Iniesta, María Jesús; Viñas, Pilar; Hernández-Córdoba, Manuel

    2015-01-01

    Seven strobilurin fungicides were pre-concentrated from soya-based drinks using dispersive liquid-liquid micro-extraction (DLLME) with a prior protein precipitation step in acid medium. The enriched phase was analysed by liquid chromatography (LC) with dual detection, using diode array detection (DAD) and electrospray-ion trap tandem mass spectrometry (ESI-IT-MS/MS). After selecting 1-undecanol and methanol as the extractant and disperser solvents, respectively, for DLLME, the Taguchi experimental method, an orthogonal array design, was applied to select the optimal solvent volumes and salt concentration in the aqueous phase. The matrix effect was evaluated and quantification was carried out using external aqueous calibration for DAD and matrix-matched calibration method for MS/MS. Detection limits in the 4-130 and 0.8-4.5 ng g(-1) ranges were obtained for DAD and MS/MS, respectively. The DLLME-LC-DAD-MS method was applied to the analysis of 10 different samples, none of which was found to contain residues of the studied fungicides.

  10. CYP1A1 induction and CYP3A4 inhibition by the fungicide imazalil in the human intestinal Caco-2 cells-comparison with other conazole pesticides.

    Science.gov (United States)

    Sergent, Thérèse; Dupont, Isabelle; Jassogne, Coralie; Ribonnet, Laurence; van der Heiden, Edwige; Scippo, Marie-Louise; Muller, Marc; McAlister, Dan; Pussemier, Luc; Larondelle, Yvan; Schneider, Yves-Jacques

    2009-02-10

    Imazalil (IMA) is a widely used imidazole-antifungal pesticide and, therefore, a food contaminant. This compound is also used as a drug (enilconazole). As intestine is the first site of exposure to ingested drugs and pollutants, we have investigated the effects of IMA, at realistic intestinal concentrations, on xenobiotic-metabolizing enzymes and efflux pumps by using Caco-2 cells, as a validated in vitro model of the human intestinal absorptive epithelium. For comparison, other conazole fungicides, i.e. ketoconazole, propiconazole and tebuconazole, were also studied. IMA induced cytochrome P450 (CYP) 1A1 activity to the same extent as benzo(a)pyrene (B(a)P) or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), in a dose- and time-dependent manner. Cell-free aryl hydrocarbon receptor (AhR) binding assay and reporter gene assay suggested that IMA is not an AhR-ligand, implying that IMA-mediated induction should involve an AhR-independent pathway. Moreover, IMA strongly inhibited the CYP3A4 activity in 1,25-vitamin D(3)-induced Caco-2 cells. The other fungicides had weak or nil effects on CYP activities. Study of the apical efflux pump activities revealed that ketoconazole inhibited both P-glycoprotein (Pgp) and multidrug resistance-associated protein 2 (MRP-2) or breast cancer resistance protein (BCRP), whereas IMA and other fungicides did not. Our results imply that coingestion of IMA-contaminated food and CYP3A4- or CYP1A1-metabolizable drugs or chemicals could lead to drug bioavailability modulation or toxicological interactions, with possible adverse effects for human health.

  11. Comparative assessment of herbicide and fungicide runoff risk: a case study for peanut production in the Southern Atlantic Coastal Plain (USA).

    Science.gov (United States)

    Potter, Thomas L; Bosch, David D; Strickland, Timothy C

    2014-08-15

    Peanut (Arachis hypogaea) is produced intensively in the southern Atlantic Coastal Plain of the eastern USA. To effectively protect the region's water quality data are needed which quantify runoff of pesticides used to protect these crops. Fungicides are used intensively yet there is little published data which describe their potential for loss in surface runoff. This study compared runoff of a fungicide, tebuconazole (α-[2-(4-chlorophenyl)ethyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol), and an herbicide, metolachlor (2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide) from 0.2 ha fields in strip (ST), a commonly used conservation-tillage practice, and conventional tillage (CT) near Tifton, GA (USA). Following their first application, metolachlor and tebuconazole were detected at high frequency in runoff. Concentrations and their annual losses increased with application frequency and runoff event timing and frequency with respect to applications, and when fields were positioned at the top of the slope and CT was practiced. Runoff one day after treatment (DAT) contributed to high tebuconazole runoff loss, up to 9.8% of the amount applied on an annual basis. In all cases, metolachlor loss was more than 10 times less even though total application was 45% higher. This was linked to the fact that the one metolachlor application to each crop was in May, one of the region's driest months. In sum, studies showed that fungicide runoff rates may be relatively high and emphasize the need to focus on these products in future studies on peanut and other crops. The study also showed that peanut farmers should be encouraged to use conservation tillage practices like ST which can substantially reduce pesticide runoff. Published by Elsevier B.V.

  12. Minimum Q Electrically Small Antennas

    DEFF Research Database (Denmark)

    Kim, O. S.

    2012-01-01

    Theoretically, the minimum radiation quality factor Q of an isolated resonance can be achieved in a spherical electrically small antenna by combining TM1m and TE1m spherical modes, provided that the stored energy in the antenna spherical volume is totally suppressed. Using closed-form expressions...... for a multiarm spherical helix antenna confirm the theoretical predictions. For example, a 4-arm spherical helix antenna with a magnetic-coated perfectly electrically conducting core (ka=0.254) exhibits the Q of 0.66 times the Chu lower bound, or 1.25 times the minimum Q....

  13. Probing the fungicidal property of CdS quantum dots on Saccharomyces cerevisiae and Candida utilis using MALDI-MS

    International Nuclear Information System (INIS)

    Manikandan, Muthu; Wu, Hui-Fen

    2013-01-01

    For the first time, we report the successful application of inhouse synthesized CdS quantum dots (QDs) with particle sizes between 1 and 7 nm exhibiting excellent fungicidal activity based on the interactions with Saccharomyces cerevisiae and Candida utilis. The growth curves and the growth rates of both fungi were established in the presence of three varying concentrations of CdS QDs. It was observed that the CdS QDs were highly inhibitory even at the lowest concentration of 10 mg/L used in this study, while the untreated control cells followed a normal growth pattern in the cases of both Saccharomyces and Candida. MALDI-MS was applied to substantiate the observations obtained by direct cell count method. It was observed that the trend observed in the case of Saccharomyces and Candida was well-represented in the MALDI-MS spectra. This study proposes a mechanism for the first time based on MALDI-MS results, that the CdS QDs interact with the extracellular polymeric substances (EPS) and remove small molecules from EPS layer; on the other hand, it was observed that CdS QDs at all concentrations lead to enrichment of protein signals in MALDI-MS. We have substantiated these results by quantifying the EPS in the control and treated cells and also using TEM to further confirm the results

  14. Probing the fungicidal property of CdS quantum dots on Saccharomyces cerevisiae and Candida utilis using MALDI-MS

    Energy Technology Data Exchange (ETDEWEB)

    Manikandan, Muthu; Wu, Hui-Fen, E-mail: hwu@faculty.nsysu.edu.tw [National Sun Yat-Sen University, Department of Chemistry (China)

    2013-07-15

    For the first time, we report the successful application of inhouse synthesized CdS quantum dots (QDs) with particle sizes between 1 and 7 nm exhibiting excellent fungicidal activity based on the interactions with Saccharomyces cerevisiae and Candida utilis. The growth curves and the growth rates of both fungi were established in the presence of three varying concentrations of CdS QDs. It was observed that the CdS QDs were highly inhibitory even at the lowest concentration of 10 mg/L used in this study, while the untreated control cells followed a normal growth pattern in the cases of both Saccharomyces and Candida. MALDI-MS was applied to substantiate the observations obtained by direct cell count method. It was observed that the trend observed in the case of Saccharomyces and Candida was well-represented in the MALDI-MS spectra. This study proposes a mechanism for the first time based on MALDI-MS results, that the CdS QDs interact with the extracellular polymeric substances (EPS) and remove small molecules from EPS layer; on the other hand, it was observed that CdS QDs at all concentrations lead to enrichment of protein signals in MALDI-MS. We have substantiated these results by quantifying the EPS in the control and treated cells and also using TEM to further confirm the results.

  15. Energetic endpoints provide early indicators of life history effects in a freshwater gastropod exposed to the fungicide, pyraclostrobin.

    Science.gov (United States)

    Fidder, Bridgette N; Reátegui-Zirena, Evelyn G; Olson, Adric D; Salice, Christopher J

    2016-04-01

    Organismal energetics provide important insights into the effects of environmental toxicants. We aimed to determine the effects of pyraclostrobin on Lymnaea stagnalis by examining energy allocation patterns and life history traits. Juvenile snails exposed to pyraclostrobin decreased feeding rate and increased apparent avoidance behaviors at environmentally relevant concentrations. In adults, we found that sublethal concentrations of pyraclostrobin did not affect reproductive output, however, there were significant effects on developmental endpoints with longer time to hatch and decreased hatching success in pyraclostrobin-exposed egg masses. Further, there were apparent differences in developmental effects depending on whether mothers were also exposed to pyraclostrobin suggesting this chemical can exert intergenerational effects. Pyraclostrobin also affected protein and carbohydrate content of eggs in mothers that were exposed to pyraclostrobin. Significant effects on macronutrient content of eggs occurred at lower concentrations than effects on gross endpoints such as hatching success and time to hatch suggesting potential value for these endpoints as early indicators of ecologically relevant stress. These results provide important insight into the effects of a common fungicide on important endpoints for organismal energetics and life history. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Predictive value of cell assays for developmental toxicity and embryotoxicity of conazole fungicides

    DEFF Research Database (Denmark)

    Sørensen, Karin Dreisig; Taxvig, Camilla; Kjærstad, Mia Birkhøj

    2013-01-01

    in reasonably good agreement with available in vivo effects. Ketoconazole and epoxiconazole are the most potent embryotoxic compounds, whereas prochloraz belongs to the most potent developmental toxicants. In conclusion, a rough prediction of the ranking of these conazole fungicides for in vivo toxicity data...

  17. RAMAN SPECTROSCOPY-BASED METABOLOMICS FOR DIFFERENTIATING TOXICITIES OF TRIAZOLE FUNGICIDES

    Science.gov (United States)

    Conazole fungicides are widely used both agriculturally for the protection of crops, and pharmaceutically in the treatment of topical and systemic infections. Heavy usage has created concern over the impact these compounds may have through environmental exposure to humans and ot...

  18. RAMAN SPECTROSCOPY-BASED METABOLOMICS FOR DIFFERENTIATING TOXICITIES OF CONAZOLE FUNGICIDES

    Science.gov (United States)

    Conazole fungicides are widely used both agriculturally for the protection of crops, and pharmaceutically in the treatment of topical and systemic infections. Heavy usage has created concern over the impact these compounds may have through environmental exposure to humans and ot...

  19. Fungicidal effect of 15 disinfectants against 24 fungal contaminants commonly found in bread and cheese manufacturing

    DEFF Research Database (Denmark)

    Bundgaard-Nielsen, Kirsten; Nielsen, Per Væggemose

    1996-01-01

    Resistance of 19 mold- and 6 yeast- species against 15 commercial disinfectants was investigated by a suspension-method in which the fungicidal effect and germination time were determined at 20 °C. Disinfectants containing 0.5 % dodecyldiethylentriaminacetic acid, 10 g/l chloramine-T, 2.0 % forma...

  20. Infectivity of the conidia of the rice blast fungus treated with the different fungicidal solutions

    Energy Technology Data Exchange (ETDEWEB)

    Hashioka, Y; Ikegami, H

    1959-01-01

    Infectivity of the conidia of Piricularia oryzae (rice blast fungus) which had been treated with different fungicides was examined. Germination of conidia treated with phenylmercuric acetate was severely repressed. Copper sulfate had a mild inhibitory effect. Organosulfur compounds also had a slight inhibitory effect.

  1. DIFFERENTIATING TOXICITIES OF CONAZOLE FUNGICIDES THROUGH METABONOMIC ANALYSES OF MULTIPLE TISSUES

    Science.gov (United States)

    The conazole fungicides represent a large group of compounds widely used agriculturally for the protection of crop plants (Hutson 1998) and pharmaceutically in the treatment of topical and systemic infections(Sheehan 1999). In 1999, the latest period for which agricultural usage...

  2. Tentative identification of 2-imidazoline as a transformation product of ethylenebisdithiocarbamate fungicides

    NARCIS (Netherlands)

    Vonk, J.W.; Kaars Sijpesteijn, A.

    2-Imidazoline has been identified tentatively as a minor conversion product of ethylenethiourea in seedlings of cucumber and wheat. As ethylenethiourea is known to be present in plants after root treatment with ethylenebisdithiocarbamate fungicides, 2-imidazoline is assumed to be a terminal residue

  3. POMICS: A Simulation Disease Model for Timing Fungicide Applications in Management of Powdery Mildew of Cucurbits.

    Science.gov (United States)

    Sapak, Z; Salam, M U; Minchinton, E J; MacManus, G P V; Joyce, D C; Galea, V J

    2017-09-01

    A weather-based simulation model, called Powdery Mildew of Cucurbits Simulation (POMICS), was constructed to predict fungicide application scheduling to manage powdery mildew of cucurbits. The model was developed on the principle that conditions favorable for Podosphaera xanthii, a causal pathogen of this crop disease, generate a number of infection cycles in a single growing season. The model consists of two components that (i) simulate the disease progression of P. xanthii in secondary infection cycles under natural conditions and (ii) predict the disease severity with application of fungicides at any recurrent disease cycles. The underlying environmental factors associated with P. xanthii infection were quantified from laboratory and field studies, and also gathered from literature. The performance of the POMICS model when validated with two datasets of uncontrolled natural infection was good (the mean difference between simulated and observed disease severity on a scale of 0 to 5 was 0.02 and 0.05). In simulations, POMICS was able to predict high- and low-risk disease alerts. Furthermore, the predicted disease severity was responsive to the number of fungicide applications. Such responsiveness indicates that the model has the potential to be used as a tool to guide the scheduling of judicious fungicide applications.

  4. Effects of four fungicides on nine non-target submersed macrophytes

    NARCIS (Netherlands)

    Belgers, J.D.M.; Aalderink, G.H.; Brink, van den P.J.

    2009-01-01

    We tested the sensitivity of nine submersed macrophyte species to the fungicides chlorothalonil, pentachlorophenol, fluazinam, and carbendazim. Endpoints determined 3 weeks after the start of the treatment were based on shoot and root growth in water. Carbendazim proved not or only moderately toxic

  5. Effects of the fungicide metiram in outdoor freshwater microcosms: responses of invertebrates, primany producers and microbes

    NARCIS (Netherlands)

    Ronghua, Lin; Buijse-Bogdan, L.L.; Rocha Dimitrov, M.; Dohmen, P.; Kosol, Sujitra; Maltby, L.; Roessink, I.; Sinkeldam, J.A.; Smidt, H.; Wijngaarden, van R.P.A.; Brock, T.C.M.

    2012-01-01

    The ecological impact of the dithiocarbamate fungicide metiram was studied in outdoor freshwater microcosms, consisting of 14 enclosures placed in an experimental ditch. The microcosms were treated three times (interval 7 days) with the formulated product BAS 222 28F (Polyram®). Intended metiram

  6. Interaction of basal foliage removal and late season fungicide applications in management of Hop powdery mildew

    Science.gov (United States)

    Experiments were conducted over three years to evaluate whether fungicide applications could be ceased after the most susceptible stages of cone development (late July) without unduly affecting crop yield and quality when disease pressure was moderated with varying levels of basal foliage removal. I...

  7. Comparing protection afforded by different organic alternatives to conventional fungicides for reducing scab on pecan

    Science.gov (United States)

    Pecan scab (Venturia effusa) is the major yield-limiting disease in the southeastern USA. Although conventional fungicides are available to manage the disease, there is no comparison of organic methods (organically produced nuts attract a higher price). In 2011, 2012, 2014, 2015 and 2016 trees of cv...

  8. Analysis of Fungicide Sensitivity and Genetic Diversity among Colletotrichum Species in Sweet Persimmon.

    Science.gov (United States)

    Gang, Geun-Hye; Cho, Hyun Ji; Kim, Hye Sun; Kwack, Yong-Bum; Kwak, Youn-Sig

    2015-06-01

    Anthracnose, caused by Colletotrichum gloeosporioides (C. gloeosporioides; Teleomorph: Glomerella cingulata), is the most destructive disease that affects sweet persimmon production worldwide. However, the biology, ecology, and genetic variations of C. gloeosporioides remain largely unknown. Therefore, in this study, the development of fungicide resistance and genetic diversity among an anthracnose pathogen population with different geographical origins and the exposure of this population to different cultivation strategies were investigated. A total of 150 pathogen isolates were tested in fungicide sensitivity assays. Five of the tested fungicides suppressed mycelial pathogen growth effectively. However, there were significant differences in the sensitivities exhibited by the pathogen isolates examined. Interestingly, the isolates obtained from practical management orchards versus organic cultivation orchards showed no differences in sensitivity to the same fungicide. PCR-restriction fragment length polymorphism (RFLP) analyses were performed to detect internal transcribed spacer regions and the β-tubulin and glutamine synthetase genes of the pathogens examined. Both the glutamine synthetase and β-tubulin genes contained a complex set of polymorphisms. Based on these results, the pathogens isolated from organic cultivation orchards were found to have more diversity than the isolates obtained from the practical management orchards.

  9. Analysis of Fungicide Sensitivity and Genetic Diversity among Colletotrichum Species in Sweet Persimmon

    Directory of Open Access Journals (Sweden)

    Geun-Hye Gang

    2015-06-01

    Full Text Available Anthracnose, caused by Colletotrichum gloeosporioides (C. gloeosporioides; Teleomorph: Glomerella cingulata, is the most destructive disease that affects sweet persimmon production worldwide. However, the biology, ecology, and genetic variations of C. gloeosporioides remain largely unknown. Therefore, in this study, the development of fungicide resistance and genetic diversity among an anthracnose pathogen population with different geographical origins and the exposure of this population to different cultivation strategies were investigated. A total of 150 pathogen isolates were tested in fungicide sensitivity assays. Five of the tested fungicides suppressed mycelial pathogen growth effectively. However, there were significant differences in the sensitivities exhibited by the pathogen isolates examined. Interestingly, the isolates obtained from practical management orchards versus organic cultivation orchards showed no differences in sensitivity to the same fungicide. PCR-restriction fragment length polymorphism (RFLP analyses were performed to detect internal transcribed spacer regions and the β-tubulin and glutamine synthetase genes of the pathogens examined. Both the glutamine synthetase and β-tubulin genes contained a complex set of polymorphisms. Based on these results, the pathogens isolated from organic cultivation orchards were found to have more diversity than the isolates obtained from the practical management orchards.

  10. Management of resistance to the fungicide fenpropimorph in Erysiphe graminis f.sp tritici

    NARCIS (Netherlands)

    Engels, A.J.G.

    1998-01-01

    In the last three decades, plant disease control has become heavily dependent on fungicides. This practice increased yield significantly but had also negative side-effects on the environment. In many countries, integrated control programs have been initiated in order to reduce pesticide use

  11. Reaction kinetics and mechanisms of organosilicon fungicide flusilazole with sulfate and hydroxyl radicals.

    Science.gov (United States)

    Mercado, D Fabio; Bracco, Larisa L B; Arques, Antonio; Gonzalez, Mónica C; Caregnato, Paula

    2018-01-01

    Flusilazole is an organosilane fungicide used for treatments in agriculture and horticulture for control of diseases. The reaction kinetics and mechanism of flusilazole with sulfate and hydroxyl radicals were studied. The rate constant of the radicals with the fungicide were determined by laser flash photolysis of peroxodisulfate and hydrogen peroxide. The results were 2.0 × 10 9 s -1 M -1 for the reaction of the fungicide with HO and 4.6 × 10 8  s -1  M -1 for the same reaction with SO 4 - radicals. The absorption spectra of organic intermediates detected by laser flash photolysis of S 2 O 8 2- with flusilazole, were identified as α-aminoalkyl and siloxyl radicals and agree very well with those estimated employing the time-dependent density functional theory with explicit account for bulk solvent effects. In the continuous photolysis experiments, performed by photo-Fenton reaction of the fungicide, the main degradation products were: (bis(4-fluorophenyl)-hydroxy-methylsilane) and the non-toxic silicic acid, diethyl bis(trimethylsilyl) ester, in ten and twenty minutes of reaction, respectively. Copyright © 2017. Published by Elsevier Ltd.

  12. Fungicidal seed coatings exert minor effects on arbuscular mycorrhizal fungi and plant nutrient content

    Science.gov (United States)

    Aims: Determine if contemporary, seed-applied fungicidal formulations inhibit colonization of plant roots by arbuscular mycorrhizal (AM) fungi, plant development, or plant nutrient content during early vegetative stages of several commodity crops. Methods: We evaluated seed-applied commercial fungic...

  13. Effects of artea, a systemic fungicide, on the antioxidant system and ...

    African Journals Online (AJOL)

    The present work aimed at the study of the effects of Artea, a systemic azole fungicide, on durum Wheat (Triticum durum L. cv. GTA dur). Seeds were grown in a medium containing respectively 25, 50, 75 and 100 ppm of Artea under controlled conditions. Roots of eight-day-old plants were used to determine catalase, ...

  14. Non-target effects of fungicides on nectar-inhabiting fungi of almond flowers.

    Science.gov (United States)

    Schaeffer, Robert N; Vannette, Rachel L; Brittain, Claire; Williams, Neal M; Fukami, Tadashi

    2017-04-01

    Nectar mediates interactions between plants and pollinators in natural and agricultural systems. Specialized microorganisms are common nectar inhabitants, and potentially important mediators of plant-pollinator interactions. However, their diversity and role in mediating pollination services in agricultural systems are poorly characterized. Moreover, agrochemicals are commonly applied to minimize crop damage, but may present ecological consequences for non-target organisms. Assessment of ecological risk has tended to focus on beneficial macroorganisms such as pollinators, with less attention paid to microorganisms. Here, using culture-independent methods, we assess the impact of two widely-used fungicides on nectar microbial community structure in the mass-flowering crop almond (Prunus dulcis). We predicted that fungicide application would reduce fungal richness and diversity, whereas competing bacterial richness would increase, benefitting from negative effects on fungi. We found that fungicides reduced fungal richness and diversity in exposed flowers, but did not significantly affect bacterial richness, diversity, or community composition. The relative abundance of Metschnikowia OTUs, nectar specialists that can impact pollination, was reduced by both fungicides. Given growing recognition of the importance of nectar microorganisms as mediators of plant-pollinator mutualisms, future research should consider the impact of management practices on plant-associated microorganisms and consequences for pollination services in agricultural landscapes. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  15. Effect of fungicide on the development of wheat stem rust and yield ...

    African Journals Online (AJOL)

    Stem rust caused by Puccinia graminis f.sp tritici Erik. & E. Henn. is a highly destructive disease of wheat (Triticum aestivum L.). The effects of fungicide application on stem rust (Puccinia graminis tritici) epidemics and yield of three bread wheat varieties varying in reaction to the disease were studied in two major wheat ...

  16. Comparative assessment of the effect of synthetic and natural fungicides on soil respiration.

    Science.gov (United States)

    Stefani, Angelo; Felício, Joanna D'Arc; de Andréa, Mara M

    2012-01-01

    As toxic pesticide residues may persist in agricultural soils and cause environmental pollution, research on natural fungicides to replace the synthetic compounds is currently increasing. The effect of the synthetic fungicide chlorothalonil and a natural potential fungicide on the soil microbial activity was evaluated here by the substrate-induced respiration by addition of glucose (SIR), as bioindicator in two soils (Eutrophic Humic Gley-GHE and Typic Eutroferric Chernosol-AVEC). The induced soil respiration parameter was followed during 28 days after soil treatment either with chlorathalonil (11 μg·g(-1)), or the methanolic fraction from Polymnia sonchifolia extraction (300 μg·g(-1)), and (14)C-glucose (4.0 mg and 5.18 Bq of (14)C-glucose g(-1)). The (14)C-CO(2) produced by the microbial respiration was trapped in NaOH (0.1 M) which was changed each two hours during the first 10 h, and 1, 3, 5, 7, 14 and 28 days after the treatments. The methanolic fraction of the plant extract inhibited (2.2%) and stimulated (1.8%) the respiration of GHE and AVEC, respectively, but the synthetic chlorothalonil caused 16.4% and 2.6% inhibition of the respiration, respectively of the GHE and AVEC soils. As the effects of the natural product were statistically small, this bioindicator indicates that the methanolic fraction of the Polymnia sonchifolia extract, which has fungicide properties, has no environmental effects.

  17. Comparison of human health risks resulting from exposure to fungicides and mycotoxins via food

    NARCIS (Netherlands)

    Muri, S.D.; Voet, van der H.; Boon, P.E.; Klaveren, van J.D.; Bruschweiler, B.

    2009-01-01

    The interest in holistic considerations in the area of food safety is increasing. Risk managers may face the problem that reducing the risk of one compound may increase the risk of another compound. An example is the potential increase in mycotoxin levels due to a reduced use of fungicides in crop

  18. Application of Copper Solid Amalgam Electrode for Determination of Fungicide Tebuconazole

    Czech Academy of Sciences Publication Activity Database

    Nováková, Kateřina; Navrátil, Tomáš; Jaklová Dytrtová, Jana; Chýlková, J.

    2013-01-01

    Roč. 8, č. 1 (2013), s. 1-16 ISSN 1452-3981 R&D Projects: GA ČR GAP206/11/1638; GA ČR(CZ) GAP208/12/1645 Institutional support: RVO:61388955 ; RVO:61388963 Keywords : tebuconazole * fungicide * copper solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 1.956, year: 2013

  19. In vitro metabolism of the anti-androgenic fungicide vinclozolin by rat liver microsomes

    Science.gov (United States)

    Vinclozolin (V) is a fungicide used in agricultural settings. V administered to rats is hydrolyzed to 2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3-butenoic acid (Ml) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2). V, Ml and M2 have antiandrogenic properties by in...

  20. Adsorption, transformation, and bioavailability of the fungicides carbendazim and iprodione in soil, alone and in combination

    NARCIS (Netherlands)

    Leistra, M.; Matser, A.M.

    2004-01-01

    When studying the effect of mixtures of toxic substances on soil organisms, attention must be paid to peculiarities in exposure to mixtures as opposed to that of single toxicants. The fungicides carbendazim and iprodione compete in the adsorption to soil. The presence of iprodione reduced the

  1. Using airborne imagery to monitor cotton root rot infection before and after fungicide treatment

    Science.gov (United States)

    Cotton root rot is a severe soilborne disease that has affected cotton production for over a century. Recent research has shown that a commercial fungicide, flutriafol, has potential for the control of this disease. To effectively and economically control this disease, it is necessary to identify in...

  2. Evaluation of fungicides for the control of false smut of rice caused ...

    African Journals Online (AJOL)

    Benomyl, Copper Oxychloride, Iprodione, Thiabendazole (TBZ) and Mancozeb were evaluated both in the laboratory and field study in 1994, for the control of false smut of rice caused by Ustilaginoidea virens (Cooke) Tak. in upland rice in Edo State, Nigeria. In the laboratory the fungicides were evaluated at three ...

  3. Development and persistence of resistance to fungicides in Sphaerotheca fuliginea in cucumbers in the Netherlands

    NARCIS (Netherlands)

    Schepers, H.T.A.M.

    1985-01-01

    Ergosterol biosynthesis inhibitors (EBIs) have a remarkably broad spectrum of antifungal activity. They belong to the commercial fungicides which exhibit the highest activity known to date. Resistance to EBIs was found in vitro, but the level of resistance and the decreased fitness of resistant

  4. Evaluation of fungicides to protect pruning wounds from Botryosphaeriaceae species infections on almond trees

    Directory of Open Access Journals (Sweden)

    Diego OLMO

    2017-05-01

    Full Text Available In vitro efficacy of ten fungicides was evaluated against four Botryosphaeriaceae spp. (Diplodia seriata, Neofusicoccum luteum, N. mediterraneum and N. parvum associated with branch cankers on almond trees. Cyproconazole, pyraclostrobin, tebuconazole, and thiophanate-methyl were effective for the inhibition of mycelial growth of most of these fungi. An experiment on 3-year-old almond trees evaluated boscalid, mancozeb, thiophanate-methyl, pyraclostrobin and tebuconazole for preventative ability against infections caused by the four pathogens. Five months after pruning and fungicide application, lesion length measurements and isolation percentages showed no significant differences among the four pathogens after they were inoculated onto the trees, and also between the two inoculation times tested (1 or 7 d after fungicide application. Thiophanate-methyl was the most effective fungicide, resulting in the shortest lesion lengths and the lowest isolation percentages from artificially inoculated pruning wounds. This chemical is therefore a candidate for inclusion in integrated disease management, to protect pruning wounds from infections caused by species of Botryosphaeriaceae. This study represents the first approach to development of chemical control strategies for the management of canker diseases caused by Botryosphaeriaceae fungi on almond trees. 

  5. Fungicides efficiency on wheat diseases control in response to the application with different spray nozzles

    Directory of Open Access Journals (Sweden)

    Felipe Rafael Garcés Fiallos

    2011-12-01

    Full Text Available This study aimed to evaluate the efficiency of fungicides to leaf control diseases of wheat, when applied to different models of spray nozzles. The experiment was conducted in a randomized block design with four replicates of factorial (4 x 3+1. Data were subjected to analysis of variance and means compared by Tukey test at 5% probability. The fungicides used were: Opera® (pyraclostrobin+epoxiconazole 0.75 L.ha-1 , Opera® 0.75 L.ha-1 +Folicur® (tebuconazole 0.3 L.ha-1 , Priori Xtra® (azoxystrobin+cyproconazole 0.3 L.ha-1 , Priori Xtra® 0.3 L.ha-1 +Tilt® (propiconazole 0.3 L.ha-1 . These fungicides were applied with three models of spray nozzles jet planes: XR 11 001 (fine drop, AIRMIX 11,001 (average drop and AVI 11,001 (coarse drop. We evaluated the incidence and severity (damage per plant leaf of yellow spot (Drechslera tritici-repentis, spot blotch (Bipolaris sorokiniana, leaf rust (Puccinia triticina and grain yield (kg.ha-1 culture. The results show that the application of fungicides for control of leaf diseases in wheat resulted in increases in grain yield, and yield higher values were observed with the application of Opera®, using the XR 11001.

  6. A reassessment of the risk of rust fungi developing resistance to fungicides.

    Science.gov (United States)

    Oliver, Richard P

    2014-11-01

    Rust fungi are major pathogens of many annual and perennial crops. Crop protection is largely based on genetic and chemical control. Fungicide resistance is a significant issue that has affected many crop pathogens. Some pathogens have rapidly developed resistance and hence are regarded as high-risk species. Rust fungi have been classified as being low risk, in spite of sharing many relevant features with high-risk pathogens. An examination of the evidence suggests that rust fungi may be wrongly classified as low risk. Of the nine classes of fungicide to which resistance has developed, six are inactive against rusts. The three remaining classes are quinone outside inhibitors (QoIs), demethylation inhibitors (DMIs) and succinate dehydrogenase inhibitors (SDHIs). QoIs have been protected by a recently discovered intron that renders resistant mutants unviable. Low levels of resistance have developed to DMIs, but with limited field significance. Older SDHI fungicides were inactive against rusts. Some of the SDHIs introduced since 2003 are active against rusts, so it may be that insufficient time has elapsed for resistance to develop, especially as SDHIs are generally sold in mixtures with other actives. It would therefore seem prudent to increase the level of vigilance for possible cases of resistance to established and new fungicides in rusts. © 2014 Society of Chemical Industry.

  7. Fermat and the Minimum Principle

    Indian Academy of Sciences (India)

    Arguably, least action and minimum principles were offered or applied much earlier. This (or these) principle(s) is/are among the fundamental, basic, unifying or organizing ones used to describe a variety of natural phenomena. It considers the amount of energy expended in performing a given action to be the least required ...

  8. Coupling between minimum scattering antennas

    DEFF Research Database (Denmark)

    Andersen, J.; Lessow, H; Schjær-Jacobsen, Hans

    1974-01-01

    Coupling between minimum scattering antennas (MSA's) is investigated by the coupling theory developed by Wasylkiwskyj and Kahn. Only rotationally symmetric power patterns are considered, and graphs of relative mutual impedance are presented as a function of distance and pattern parameters. Crossed...

  9. Efficacy of Combined Formulations of Fungicides with Different Modes of Action in Controlling Botrytis Gray Mold Disease in Chickpea

    Science.gov (United States)

    Rashid, M. H.; Hossain, M. Ashraf; Kashem, M. A.; Kumar, Shiv; Rafii, M. Y.; Latif, M. A.

    2014-01-01

    Botrytis gray mold (BGM) caused by Botrytis cinerea Pers. Ex. Fr. is an extremely devastating disease of chickpea (Cicer arietinum L.) and has a regional as well as an international perspective. Unfortunately, nonchemical methods for its control are weak and ineffective. In order to identify an effective control measure, six fungicides with different modes of action were evaluated on a BGM susceptible chickpea variety BARIchhola-1 at a high BGM incidence location (Madaripur) in Bangladesh for three years (2008, 2009, and 2010). Among the six fungicides tested, one was protectant [Vondozeb 42SC, a.i. mancozeb (0.2%)], two systemic [Bavistin 50 WP, a.i. carbendazim (0.2%), and Protaf 250EC, propiconazole (0.05%)], and three combination formulations [Acrobat MZ690, dimethomorph 9% + mancozeb 60%, (0.2%); Secure 600 WG, phenomadone + mancozeb (0.2%); and Companion, mancozeb 63% + carbendazim 12% (0.2%)]. The results showed superiority of combination formulations involving both protectant and systemic fungicides over the sole application of either fungicide separately. Among the combination fungicides, Companion was most effective, resulting in the lowest disease severity (3.33 score on 1–9 scale) and the highest increase (38%) of grain yield in chickpea. Therefore, this product could be preferred over the sole application of either solo protectant or systemic fungicides to reduce yield losses and avoid fungicide resistance. PMID:24723819

  10. Interactive Role of Fungicides and Plant Growth Regulator (Trinexapac on Seed Yield and Oil Quality of Winter Rapeseed

    Directory of Open Access Journals (Sweden)

    Muhammad Ijaz

    2015-09-01

    Full Text Available This study was designed to evaluate the role of growth regulator trinexapac and fungicides on growth, yield, and quality of winter rapeseed (Brassica napus L.. The experiment was conducted simultaneously at different locations in Germany using two cultivars of rapeseed. Five different fungicides belonging to the triazole and strobilurin groups, as well as a growth regulator trinexapac, were tested in this study. A total of seven combinations of these fungicides and growth regulator trinexapac were applied at two growth stages of rapeseed. These two stages include green floral bud stage (BBCH 53 and the course of pod development stage (BBCH 65. The results showed that plant height and leaf area index were affected significantly by the application of fungicides. Treatments exhibited induced photosynthetic ability and delayed senescence, which improved the morphological characters and yield components of rape plants at both locations. Triazole, in combination with strobilurin, led to the highest seed yield over other treatments at both experimental locations. Significant effects of fungicides on unsaturated fatty acids of rapeseed oil were observed. Fungicides did not cause any apparent variation in the values of free fatty acids and peroxide of rapeseed oil. Results of our study demonstrate that judicious use of fungicides in rapeseed may help to achieve sustainable farming to obtain higher yield and better quality of rapeseed.

  11. Colonies of Bumble Bees (Bombus impatiens Produce Fewer Workers, Less Bee Biomass, and Have Smaller Mother Queens Following Fungicide Exposure

    Directory of Open Access Journals (Sweden)

    Olivia M. Bernauer

    2015-06-01

    Full Text Available Bees provide vital pollination services to the majority of flowering plants in both natural and agricultural systems. Unfortunately, both native and managed bee populations are experiencing declines, threatening the persistence of these plants and crops. Agricultural chemicals are one possible culprit contributing to bee declines. Even fungicides, generally considered safe for bees, have been shown to disrupt honey bee development and impair bumble bee behavior. Little is known, however, how fungicides may affect bumble bee colony growth. We conducted a controlled cage study to determine the effects of fungicide exposure on colonies of a native bumble bee species (Bombus impatiens. Colonies of B. impatiens were exposed to flowers treated with field-relevant levels of the fungicide chlorothalonil over the course of one month. Colony success was assessed by the number and biomass of larvae, pupae, and adult bumble bees. Bumble bee colonies exposed to fungicide produced fewer workers, lower total bee biomass, and had lighter mother queens than control colonies. Our results suggest that fungicides negatively affect the colony success of a native bumble bee species and that the use of fungicides during bloom has the potential to severely impact the success of native bumble bee populations foraging in agroecosystems.

  12. Multiple resistance of Botrytis cinerea from kiwifruit to SDHIs, QoIs and fungicides of other chemical groups.

    Science.gov (United States)

    Bardas, George A; Veloukas, Thomas; Koutita, Olga; Karaoglanidis, George S

    2010-09-01

    Botrytis cinerea Pers.: Fr. is a high-risk pathogen for fungicide resistance development that has caused resistance problems on many crops throughout the world. This study investigated the fungicide sensitivity profile of isolates from kiwifruits originating from three Greek locations with different fungicide use histories. Sensitivity was measured by in vitro fungitoxicity tests on artificial nutrient media. Seventy-six single-spore isolates were tested for sensitivity to the SDHI fungicide boscalid, the QoI pyraclostrobin, the anilinopyrimidine cyprodinil, the hydroxyanilide fenhexamid, the phenylpyrrole fludioxonil, the dicarboxamide iprodione and the benzimidazole carbendazim. All isolates from Thessaloniki showed resistance to both boscalid and pyraclostrobin, while in the other two locations the fungal population was sensitive to these two fungicides. Sensitive isolates showed EC(50) values to boscalid and pyraclostrobin ranging from 0.9 to 5.2 and from 0.04 to 0.14 mg L(-1) respectively, while the resistant isolates showed EC(50) values higher than 50 mg L(-1) for boscalid and from 16 to > 50 mg L(-1) for pyraclostrobin. All QoI-resistant isolates carried the G143A mutation in cytb. Sensitivity determinations to the remaining fungicides revealed in total eight resistance phenotypes. No isolates were resistant to the fungicides fenhexamid and fludioxonil. This is the first report of B. cinerea field isolates with resistance to both boscalid and pyraclostrobin, and it strongly suggests that there may be a major problem in controlling this important pathogen on kiwifruit. (c) 2010 Society of Chemical Industry.

  13. Efficacy of Combined Formulations of Fungicides with Different Modes of Action in Controlling Botrytis Gray Mold Disease in Chickpea

    Directory of Open Access Journals (Sweden)

    M. H. Rashid

    2014-01-01

    Full Text Available Botrytis gray mold (BGM caused by Botrytis cinerea Pers. Ex. Fr. is an extremely devastating disease of chickpea (Cicer arietinum L. and has a regional as well as an international perspective. Unfortunately, nonchemical methods for its control are weak and ineffective. In order to identify an effective control measure, six fungicides with different modes of action were evaluated on a BGM susceptible chickpea variety BARIchhola-1 at a high BGM incidence location (Madaripur in Bangladesh for three years (2008, 2009, and 2010. Among the six fungicides tested, one was protectant [Vondozeb 42SC, a.i. mancozeb (0.2%], two systemic [Bavistin 50 WP, a.i. carbendazim (0.2%, and Protaf 250EC, propiconazole (0.05%], and three combination formulations [Acrobat MZ690, dimethomorph 9% + mancozeb 60%, (0.2%; Secure 600 WG, phenomadone + mancozeb (0.2%; and Companion, mancozeb 63% + carbendazim 12% (0.2%]. The results showed superiority of combination formulations involving both protectant and systemic fungicides over the sole application of either fungicide separately. Among the combination fungicides, Companion was most effective, resulting in the lowest disease severity (3.33 score on 1–9 scale and the highest increase (38% of grain yield in chickpea. Therefore, this product could be preferred over the sole application of either solo protectant or systemic fungicides to reduce yield losses and avoid fungicide resistance.

  14. Probabilities for profitable fungicide use against gray leaf spot in hybrid maize.

    Science.gov (United States)

    Munkvold, G P; Martinson, C A; Shriver, J M; Dixon, P M

    2001-05-01

    ABSTRACT Gray leaf spot, caused by the fungus Cercospora zeae-maydis, causes considerable yield losses in hybrid maize grown in the north-central United States and elsewhere. Nonchemical management tactics have not adequately prevented these losses. The probability of profitably using fungicide application as a management tool for gray leaf spot was evaluated in 10 field experiments under conditions of natural inoculum in Iowa. Gray leaf spot severity in untreated control plots ranged from 2.6 to 72.8% for the ear leaf and from 3.0 to 7.7 (1 to 9 scale) for whole-plot ratings. In each experiment, fungicide applications with propiconazole or mancozeb significantly reduced gray leaf spot severity. Fungicide treatment significantly (P fungicide applications. For one application, the probability ranged from approximately 0.06 to more than 0.99, and exceeded 0.50 in six of nine scenarios (specific experiment/hybrid). The highest probabilities occurred in the 1995 experiments with the most susceptible hybrid. Probabilities were almost always higher for a single application of propiconazole than for two applications. These results indicate that a single application of propiconazole frequently can be profitable for gray leaf spot management in Iowa, but the probability of a profitable application is strongly influenced by hybrid susceptibility. The calculation of probabilities for positive net returns was more informative than mean separation in terms of assessing the economic success of the fungicide applications.

  15. Signum, a new fungicide for control of leaf diseases in outdoor vegetables.

    Science.gov (United States)

    Callens, D; Sarrazyn, R; Evens, W

    2005-01-01

    During three years, the new fungicide Signum, containing 6.7% pyraclostrobine + 26.7 % boscalid and developed by BASF. has been evaluated in leek, carrots and cabbages in several outdoor field experiments under practical conditions and during one year in outdoor lettuce. In leek, Phytophthora porri is one of the major leaf diseases causing lesions on differ ent places on the leaves, resulting in at least extra labour costs for trimming or even worse sometimes resulting in complete crop loss. So far, crop protection consists of repeated applications of fungicides especially during autumn and winter. Pyraclostrobin + boscalid has been evaluated in comparison with the fungicides mancozeb, mancozeb + metalaxyl-M and azoxystrobin. The progress of the disease during the growth season is discussed. For all parameters evaluated, pyraclostrobin + boscalid gave comparable or even better results than reference products. Especially during 2003, a small drop of the activity of benalaxyl against P. porri has been observed after repeated applications. In carrots, Erisiphe heraclei and Alternaria dauci are both the most common leaf diseases causing yield and quality loss. During periods of very high pressure of A. dauci, pyraclostrobin + boscalid, applied in a three weeks interval, revealed a superior activity compared with triazole references or compared with azoxystrobin. Against E. heraclei, a good control but also a clear dose response activity have been observed with pyraclostrobin + boscalid. Yield gain was approximately 30 ton /ha compared wih untreated. In Brussels sprouts, good efficacy was obtained against Mycosphaerella spp., Albugo candida and Alternaria spp. In outdoor lettuce Botrytis cinerea and Sclerotinia sclerotiorum are the most important diseases causing crop damage and reducing the quality of the heads. Pyraclostrobin + boscalid was evaluated in comparison with the standard fungicide iprodione. The plant protection was better with the new fungicide

  16. FUNGICIDES IN SECOND HARVEST CORN: CERCOSPORIOSE CONTROL AND BLOTCH, PRODUCTIVITY, ECONOMIC RETURN AND GRAIN QUALITY

    Directory of Open Access Journals (Sweden)

    P. Rezende

    2017-10-01

    Full Text Available Os objetivos desse trabalho foram avaliar a eficiência de The aim of this study was evaluate efficacy fungicides to control cercospora leaf spot (Cercospora zeae-maydis and helminthosporium leaf blight (Exserohilumturcicum, productivity, economic returns and quality of grain of corn culture of second crop in Farm Bandeirantes at Feliz Natal/MT. The treatments evaluated were: pyraclostrobina+epoxiconazol (0,7 L ha-1, trifloxistrobina+protioconazol (0,3L ha-1, azoxistrobina+cyproconazol(0,3 L ha-1, azoxystrobina (0,25 L ha-1, trifloxistrobina+ciproconazol (0,2 L ha-1 and control. Theapplicationof products occurred when corn was with 55 days, with a high propelled sprayer. The experimental design was a randomized block, with 6 treatments and 3 replications. The severity of each disease was visually determined through periodic analyses and ten plants were marked in each repetition, which were evaluated during the entire crop cycle. The data of severity obtained were used to calculate the area under disease progress curve (AUDPC. It was also obtained the production per ha, the economic return (R$ ha-1 and physiological quality of grain was evaluated by germination tests and accelerated aging of the grains. All treatments had significant difference compared to the control sample in controlling cercospora leaf spot about the control of helminthosporiumleat blight, the fungicides trifloxystrobin+prothioconazol and trifloxystrobin+cyproconazol were not efficient, and the fungicides pyraclostrobina+epoxiconazol, azoxystrobina, azoxistrobina+cyproconazol were efficient. The treatments that had major production are from the group of triazoles+strobilurine and the fungicide pyraclostrobin+epoxyconazol showed greater economic viability. Not were differences among fungicides, and neither of the treatments compared to control, in germination and accelerated aging tests, showing that the grains have good quality characteristics

  17. Disease control by chemical and biological fungicides in cultivated mushrooms: button mushroom, oyster mushroom and shiitake

    Directory of Open Access Journals (Sweden)

    Ivana Potočnik

    2015-12-01

    Full Text Available The most commonly cultivated basidiomycetes worldwide and in Serbia are button mushroom (Agaricus bisporus, oyster mushroom (Pleurotus sp. and shiitake (Lentinus edodes. Production of their fruiting bodies is severely afflicted by fungal, bacterial, and viral pathogens that are able to cause diseases which affect yield and quality. Major A. bisporus fungal pathogens include Mycogone perniciosa, Lecanicillium fungicola, and Cladobotryum spp., the causal agents of dry bubble, wet bubble, and cobweb disease, respectively. Various Trichoderma species, the causal agents of green mould, also affect all three kinds of edible mushrooms. Over the past two decades, green mould caused by T. aggressivum has been the most serious disease of button mushroom. Oyster mushroom is susceptible to T. pleurotum and shiitake to T. harzianum. The bacterial brawn blotch disease, caused by Pseudomonas tolaasii, is distributed globally. Disease control on mushroom farms worldwide is commonly based on the use of fungicides. However, evolution of pathogen resistance to fungicides after frequent application, and host sensitivity to fungicides are serious problems. Only a few fungicides are officially recommended in mushroom production: chlorothalonil and thiabendazol in North America and prochloraz in the EU and some other countries. Even though decreased sensitivity levels of L. fungicola and Cladobotryum mycophilum to prochloraz have been detected, disease control is still mainly provided by that chemical fungicide. Considering such resistance evolution, harmful impact to the environment and human health, special attention should be focused on biofungicides, both microbiological products based on Bacillus species and various natural substances of biological origin, together with good programs of hygiene. Introduction of biofungicides has created new possibilities for crop protection with reduced application of chemicals.

  18. Experimental investigations of the minimum ignition energy and the minimum ignition temperature of inert and combustible dust cloud mixtures

    International Nuclear Information System (INIS)

    Addai, Emmanuel Kwasi; Gabel, Dieter; Krause, Ulrich

    2016-01-01

    Highlights: • Ignition sensitivity of a highly flammable dust decreases upon addition of inert dust. • Minimum ignition temperature of a highly flammable dust increases when inert concentration increase. • Minimum ignition energy of a highly flammable dust increases when inert concentration increase. • The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%. - Abstract: The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%.

  19. Experimental investigations of the minimum ignition energy and the minimum ignition temperature of inert and combustible dust cloud mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Addai, Emmanuel Kwasi, E-mail: emmanueladdai41@yahoo.com; Gabel, Dieter; Krause, Ulrich

    2016-04-15

    Highlights: • Ignition sensitivity of a highly flammable dust decreases upon addition of inert dust. • Minimum ignition temperature of a highly flammable dust increases when inert concentration increase. • Minimum ignition energy of a highly flammable dust increases when inert concentration increase. • The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%. - Abstract: The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%.

  20. [In vitro susceptibility of Trichoconiella padwickii to various active ingredients used as fungicides in the cultivation of rice].

    Science.gov (United States)

    Lovato Echeverria, Alfonso D; Gutiérrez, Susana A; Carmona, Marcelo A

    The aim of this study was to evaluate in vitro the mycelial susceptibility of Trichoconiella padwickii to different active ingredients through average median concentration IC 50 calculation. Inoculum disks were seeded on bean agar at different concentrations (0.1; 1; 10; 30, 50; 100 and 1000mg/l) of various fungicides. After seven days the colony diameter was measured. The data obtained were fitted to nonlinear regression models. Susceptibility was classified using the scale proposed by Edgington. The results show that the pathogen is very sensitive to products that act on the respiratory chain (quinone outside inhibitors [QoI] and succinate dehydrogenase inhibitors [SDHI]) and cell membrane (multi-site contact activity), and moderately sensitive to those products interfering with cell division (methyl benzimidazole carbamates [MBC]), synthesis of nucleic acids (phenylamides [PA]) and osmotic signal transduction (multi-site contact activity). This work is the first record on the sensitivity of T. padwickii. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  1. Chronic copper toxicosis in sheep following the use of copper sulfate as a fungicide on fruit trees.

    Science.gov (United States)

    Oruc, Hasan H; Cengiz, Murat; Beskaya, Atilla

    2009-07-01

    Between January and October 2006, 15 Chios sheep died in a field located near a factory in Orhangazi, Bursa, Turkey. In addition, in May 2007, 2 ewes died after aborting in the same field. Clinical signs in affected animals prior to death were anorexia, hematuria, icterus, incoordination, and ptyalism. Postmortem findings included generalized icterus; yellow, friable livers; distended gallbladders with dense, dark bile; and dark, hypertrophic kidneys with hemorrhage. Copper (Cu) concentrations were measured in multiple specimens of the following: 9 sera, 3 livers, 3 kidneys, 4 plants (including 2 artichoke leaf specimens), 3 soil samples, and 1 drinking water sample. High Cu concentrations were present in the livers, kidneys, and sera of dead sheep, as well as in the vegetation and soil samples from the field. Chronic Cu toxicosis was confirmed as the cause of death attributed primarily to the use of copper sulfate as a fungicide for fruit trees within the field. In addition, factory dust containing Cu might have been an additional factor in the toxicosis.

  2. Quantum mechanics the theoretical minimum

    CERN Document Server

    Susskind, Leonard

    2014-01-01

    From the bestselling author of The Theoretical Minimum, an accessible introduction to the math and science of quantum mechanicsQuantum Mechanics is a (second) book for anyone who wants to learn how to think like a physicist. In this follow-up to the bestselling The Theoretical Minimum, physicist Leonard Susskind and data engineer Art Friedman offer a first course in the theory and associated mathematics of the strange world of quantum mechanics. Quantum Mechanics presents Susskind and Friedman’s crystal-clear explanations of the principles of quantum states, uncertainty and time dependence, entanglement, and particle and wave states, among other topics. An accessible but rigorous introduction to a famously difficult topic, Quantum Mechanics provides a tool kit for amateur scientists to learn physics at their own pace.

  3. Minimum resolvable power contrast model

    Science.gov (United States)

    Qian, Shuai; Wang, Xia; Zhou, Jingjing

    2018-01-01

    Signal-to-noise ratio and MTF are important indexs to evaluate the performance of optical systems. However,whether they are used alone or joint assessment cannot intuitively describe the overall performance of the system. Therefore, an index is proposed to reflect the comprehensive system performance-Minimum Resolvable Radiation Performance Contrast (MRP) model. MRP is an evaluation model without human eyes. It starts from the radiance of the target and the background, transforms the target and background into the equivalent strips,and considers attenuation of the atmosphere, the optical imaging system, and the detector. Combining with the signal-to-noise ratio and the MTF, the Minimum Resolvable Radiation Performance Contrast is obtained. Finally the detection probability model of MRP is given.

  4. Understanding the Minimum Wage: Issues and Answers.

    Science.gov (United States)

    Employment Policies Inst. Foundation, Washington, DC.

    This booklet, which is designed to clarify facts regarding the minimum wage's impact on marketplace economics, contains a total of 31 questions and answers pertaining to the following topics: relationship between minimum wages and poverty; impacts of changes in the minimum wage on welfare reform; and possible effects of changes in the minimum wage…

  5. 5 CFR 551.301 - Minimum wage.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Minimum wage. 551.301 Section 551.301... FAIR LABOR STANDARDS ACT Minimum Wage Provisions Basic Provision § 551.301 Minimum wage. (a)(1) Except... employees wages at rates not less than the minimum wage specified in section 6(a)(1) of the Act for all...

  6. Synthesis and Fungicidal Activities of (Z/E-3,7-Dimethyl-2,6-octadienamide and Its 6,7-Epoxy Analogues

    Directory of Open Access Journals (Sweden)

    Mingyan Yang

    2015-11-01

    Full Text Available In order to find new lead compounds with high fungicidal activity, (Z/E-3,7-dimethyl-2,6-octadienoic acids were synthesized via selective two-step oxidation using the commercially available geraniol/nerol as raw materials. Twenty-eight different (Z/E-3,7-dimethyl-2,6-octadienamide derivatives were prepared by reactions of (Z/E-carboxylic acid with various aromatic and aliphatic amines, followed by oxidation of peroxyacetic acid to afford their 6,7-epoxy analogues. All of the compounds were characterized by HR-ESI-MS and 1H-NMR spectral data. The preliminary bioassays showed that some of these compounds exhibited good fungicidal activities against Rhizoctonia solani (R. solani at a concentration of 50 µg/mL. For example, 5C, 5I and 6b had 94.0%, 93.4% and 91.5% inhibition rates against R. solani, respectively. Compound 5f displayed EC50 values of 4.3 and 9.7 µM against Fusahum graminearum and R. Solani, respectively.

  7. Determination of strobilurin fungicide residues in fruits and vegetables by nonaqueous micellar electrokinetic capillary chromatography with indirect laser-induced fluorescence.

    Science.gov (United States)

    Guo, Xin; Wang, Kun; Chen, Guan-Hua; Shi, Jie; Wu, Xian; Di, Lu-Lu; Wang, Yi

    2017-08-01

    A nonaqueous micellar electrokinetic capillary chromatography method with indirect LIF was developed for the determination of strobilurin fungicide residues in fruits and vegetables. Hydrophobic CdTe quantum dots (QDs) synthesized in aqueous phase were used as background fluorescent substance. The BGE solution, QD concentration, and separation voltage were optimized to obtain the best separation efficiency and the highest signal intensity. The optimal BGE solution consists of 40 mM phosphate, 120 mM sodium dodecyl sulfate, 15% v/v water and 15% v/v hydrophobic CdTe QDs in formamide, of which apparent pH is 9.5. The optimized separation voltage is controlled as 25 kV. The resultant detection limits of azoxystrobin, kresoxim-methyl, and pyraclostrobin are all 0.001 mg/kg, their linear dynamic ranges are 0.005-2.5 mg/kg, and the recoveries of the spiked samples are 81.7-96.1%, 86.5-95.7%, and 87.3-97.4%, respectively. This method has been proved to be sensitive enough to detect the aforementioned fungicides in fruits and vegetables at the maximum residue limits. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Effect of two fungicides, benlate and phenyl mercury acetate, on a population of cellulolytic fungi in soil and in pure culture

    Energy Technology Data Exchange (ETDEWEB)

    Smith, R.N.; Long, P.A.

    1980-01-01

    Cellulolytic fungi were successfully isolated from an arable loam type soil using the polythene rod technique and the screened substrate technique. Phenyl mercury acetate (PMA) applied to the soil at 100 ppm severely reduced the incidence of many cellulolytic fungi normally present, with a concomitant increase in the incidence of Penicillium spp and Trichoderma lignorum. The application of benlate at 100 ppm had little effect other than to increase the incidence of Doratomyces mircosporus, Dreschlera sp. and Papulospora sp. Both benlate and PMA were much more toxic when examined in-vitro in cellulose agar than when added to soil. Nevertheless, the incidence of cellulolytic isolates from soil reflected the relative sensitivity of the isolates to the respective fungicides in-vitro. The activity of benlate in-vitro decreased with an increase in glucose concentration in the media, but the activity of PMA was independent of glucose concentration.

  9. A new mechanism for reduced sensitivity to demethylation-inhibitor fungicides in the fungal banana black Sigatoka pathogen Pseudocercospora fijiensis

    NARCIS (Netherlands)

    Díaz-Trujillo, C.; Chong, P.; Stergiopoulos, I.; Meijer, H.J.G.; Wit, de P.J.G.M.; Kema, G.H.J.

    2018-01-01

    The Dothideomycete Pseudocercospora fijiensis, previously Mycosphaerella fijiensis, is the causal agent of black Sigatoka, one of the most destructive diseases of bananas and plantains. Disease management depends on fungicide applications with a major share for sterol demethylation-inhibitors

  10. A new mechanism for reduced sensitivity to demethylation-inhibitor fungicides in the fungal banana black Sigatoka pathogen Pseudocercospora fijiensis

    NARCIS (Netherlands)

    Díaz-Trujillo, C.; Chong, P.; Stergiopoulos, I.; Meijer, H.J.G.; Wit, de P.J.G.M.; Kema, G.H.J.

    2017-01-01

    The Dothideomycete Pseudocercospora fijiensis, previously Mycosphaerella fijiensis, is the causal agent of black Sigatoka, one of the most destructive diseases of bananas and plantains. Disease management depends on fungicide applications with a major share for sterol demethylation-inhibitors

  11. Determination of tetrahydrophtalimide and 2-thiothiazolidine-4-carboxylic acid, urinary metabolites of the fungicide captan, in rats and humans

    NARCIS (Netherlands)

    van Welie, R.T.H.; van Duyn, P; Lamme, E K; Jäger, P; van Baar, B L; Vermeulen, N P

    1991-01-01

    Capillary gas chromatographic (GC) methods using sulphur and mass selective detection for the qualitative and quantitative determination of tetrahydrophtalimide (THPI) and 2-thiothiazolidine-4-carboxylic acid (TTCA), urinary metabolites of the fungicide captan in rat and humans, were developed.

  12. Effect of the vigour and of the fungicide treatment in the germination and sanity tests of soybean seeds

    OpenAIRE

    Gomes, Delineide Pereira; Barrozo, Leandra Matos; Souza, Apolyana Lorraine; Sader, Rubens [UNESP; Silva, Gilvania Campos [UNESP

    2009-01-01

    Soybeans seeds with different levels of vigour, treated and or no with fungicide were submitted to the test of germination in the sand and roll substrates of paper and the test of sanity. In test of germination, there were only significant differences between treatments that used soybeans with high vigour and with low vigour, regardless of the presence or absence of fungicide treatment, in the two substrates. The soybeans with low vigour no treated provided the largest percentages of seed con...

  13. Influence of the fungicide Folcidin on the distribution and metabolism of /sup 32/P in gherkin plants

    Energy Technology Data Exchange (ETDEWEB)

    Hanker, I; Kudelova, A; Taimr, L [Vyzkumne Ustavy Rostlinne Vyroby, Prague (Czechoslovakia). Ustav Ochrany Rostlin; Friedrich, A [Ceskoslovenska Akademie Ved, Prague. Ustav Experimentalni Botaniky

    1976-01-01

    A high accumulation of /sup 32/P was observed in the leaves of intact gherkin plants 9 days after their roots had been treated with a 0.005% suspension of the systemic fungicide Folcidin 50WP (cypendazole), and 8 days after the roots had been exposed to labelled phosphate. Folcidin also affected phosphorus metabolism in the plants. A high biological cytokinin-like activity of the fungicide was established using a callus cytokinin bioassay.

  14. Apyrase inhibitors enhance the ability of diverse fungicides to inhibit the growth of different plant-pathogenic fungi.

    Science.gov (United States)

    Kumar Tripathy, Manas; Weeraratne, Gayani; Clark, Greg; Roux, Stanley J

    2017-09-01

    A previous study has demonstrated that the treatment of Arabidopsis plants with chemical inhibitors of apyrase enzymes increases their sensitivity to herbicides. In this study, we found that the addition of the same or related apyrase inhibitors could potentiate the ability of different fungicides to inhibit the growth of five different pathogenic fungi in plate growth assays. The growth of all five fungi was partially inhibited by three commonly used fungicides: copper octanoate, myclobutanil and propiconazole. However, when these fungicides were individually tested in combination with any one of four different apyrase inhibitors (AI.1, AI.10, AI.13 or AI.15), their potency to inhibit the growth of five fungal pathogens was increased significantly relative to their application alone. The apyrase inhibitors were most effective in potentiating the ability of copper octanoate to inhibit fungal growth, and least effective in combination with propiconazole. Among the five pathogens assayed, that most sensitive to the fungicide-potentiating effects of the inhibitors was Sclerotinia sclerotiorum. Overall, among the 60 treatment combinations tested (five pathogens, four apyrase inhibitors, three fungicides), the addition of apyrase inhibitors increased significantly the sensitivity of fungi to the fungicide treatments in 53 of the combinations. Consistent with their predicted mode of action, inhibitors AI.1, AI.10 and AI.13 each increased the level of propiconazole retained in one of the fungi, suggesting that they could partially block the ability of efflux transporters to remove propiconazole from these fungi. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  15. Evaluating the combined efficacy of polymers with fungicides for protection of museum textiles against fungal deterioration in Egypt.

    Science.gov (United States)

    Abdel-Kareem, Omar

    2010-01-01

    Fungal deterioration is one of the highest risk factors for damage of historical textile objects in Egypt. This paper represents both a study case about the fungal microflora deteriorating historical textiles in the Egyptian Museum and the Coptic museum in Cairo, and evaluation of the efficacy of several combinations of polymers with fungicides for the reinforcement of textiles and their prevention against fungal deterioration. Both cotton swab technique and biodeteriorated textile part technique were used for isolation of fungi from historical textile objects. The plate method with the manual key was used for identification of fungi. The results show that the most dominant fungi isolated from the tested textile samples belong to Alternaria, Aspergillus, Chaetomium, Penicillium and Trichoderma species. Microbiological testing was used for evaluating the usefulness of the suggested conservation materials (polymers combined with fungicides) in prevention of the fungal deterioration of ancient Egyptian textiles. Textile samples were treated with 4 selected polymers combined with two selected fungicides. Untreated and treated textile samples were deteriorated by 3 selected active fungal strains isolated from ancient Egyptian textiles. This study reports that most of the tested polymers combined with the tested fungicides prevented the fungal deterioration of textiles. Treatment of ancient textiles by suggested polymers combined with the suggested fungicides not only reinforces these textiles, but also prevents fungal deterioration and increases the durability of these textiles. The tested polymers without fungicides reduce the fungal deterioration of textiles but do not prevent it completely.

  16. Changes in antioxidants potential, secondary metabolites and plant hormones induced by different fungicides treatment in cotton plants.

    Science.gov (United States)

    Mohamed, Heba Ibrahim; Akladious, Samia Ageeb

    2017-10-01

    The use of fungicides for an effective control of plant diseases has become crucial in the last decades in the agriculture system. Seeds of cotton plants were treated with systemic and contact fungicides to study the efficiency of seed dressing fungicides in controlling damping off caused by Rhizoctonia solani under greenhouse conditions and its effect on plant growth and metabolism. The results showed that Mon-cut showed the highest efficiency (67.99%) while each of Tondro and Hemixet showed the lowest efficiency (31.99%) in controlling damping off. Rhizolex T, Mon-cut and Tondro fungicides caused significant decrease in plant height, dry weight of plant, phytohormones, photosynthetic pigments, soluble sugars, soluble proteins, total free amino acids but caused significant increases in total phenols, flavonoids, antioxidant enzymes, ascorbic acid, reduced glutathione, MDA and hydrogen peroxide as compared with untreated plants. On the other hand, the other fungicides (Maxim, Hemixet and Flosan) increased all the above recorded parameters as compared with untreated plants. Our results indicated that the fungicides application could be a potential tool to increase plant growth, the antioxidative defense mechanisms and decreased infection with plant diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Degradation of three fungicides following application on strawberry and a risk assessment of their toxicity under greenhouse conditions.

    Science.gov (United States)

    Sun, Caixia; Cang, Tao; Wang, Zhiwei; Wang, Xinquan; Yu, Ruixian; Wang, Qiang; Zhao, Xueping

    2015-05-01

    The health risk to humans of pesticide application on minor crops, such as strawberry, requires quantification. Here, the dissipation and residual levels of three fungicides (pyraclostrobin, myclobutanil, and difenoconazole) were studied for strawberry under greenhouse conditions using high-performance liquid chromatography (HPLC)-tandem mass spectrometry after Quick, Easy, Cheap, Effective, Rugged, and Safe extraction. This method was validated using blank samples, with all mean recoveries of these three fungicides exceeding 80%. The residues of all three fungicides dissipated following first-order kinetics. The half-lives of pyraclostrobin, myclobutanil, and difenoconazole were 1.69, 3.30, and 3.65 days following one time application and 1.73, 5.78, and 6.30 days following two times applications, respectively. Fungicide residue was determined by comparing the estimated daily intake of the three fungicides against the acceptable daily intake. The results indicate that the potential health risk of the three fungicides was not significant in strawberry when following good agricultural practices (GAP) under greenhouse conditions.

  18. Micronuclei, nucleoplasmic bridges, and nuclear buds induced in human lymphocytes by the fungicide signum and its active ingredients (boscalid and pyraclostrobin).

    Science.gov (United States)

    Çayır, Akin; Coskun, Munevver; Coskun, Mahmut

    2014-05-01

    The aim of this study was to investigate the genotoxic and cytotoxic potential of the Signum fungicide and its active ingredients (boscalid and pyraclostrobin) on human peripheral blood lymphocytes using the cytokinesis-block micronucleus (CBMN) assay. Micronuclei (MNi), nucleoplasmic bridges (NPBs), nuclear bud (NBUDs) formations, and the cytokinesis-block proliferation index (CBPI) were evaluated in treated lymphocytes in Go (cells were treated and then kept in culture without stimulation for 24 h) and proliferation phases (cells were treated after 44 h culture in medium containing phytohemagglutinin). MN formation in lymphocytes treated in G0 statistically increased at doses of 2, 6, and 25 μg/mL signum; 0.5 and 2 μg/mL boscalid; and 0.5, 1.5, and 2 μg/mL pyraclostrobin; while NPB formation increased at a dose of 0.25 μg/mL pyraclostrobin. All concentrations of each fungicide did not statistically increase NBUD formation, while the cytotoxicity increased the dependent on concentration in lymphocytes treated in G0 . Doses of 0.5, 1, 1.5, and 3 μg/mL signum; 0.5, 1, and 1.5 μg/mL boscalid; and 0.75 μg/mL pyraclostrobin statistically increased the MN formation in proliferating lymphocytes. NPB formation increased in proliferating lymphocytes at doses of 1, 1.5, 2, and 3 μg/mL signum and at a dose of 0.75 μg/mL pyraclostrobin. In addition, a dose of 0.75 μg/mL pyraclostrobin increased NBUD frequencies. Cytotoxicity increased with increasing concentrations of each fungicide. It is concluded that signum, boscalid, and pyraclostrobin may be genotoxic and cytotoxic in vitro human peripheral blood lymphocytes in consideration of each of the two protocols. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 723-732, 2014. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.

  19. Ranking of fungicides according to risk assessments for health and environment

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Ørum, Jens Erik

    2014-01-01

    PL varies for fungicide standard rates by a factor of 10. Products including epoxiconazole generally have higher PL's due to the human health profile of this active. PL's per area, crop or product will supplement the previous pesticide statistics based on treatment frequency index (TFI). PL has also......Denmark has introduced a new indicator for ranking the potential impact of pesticides on health and environment. The new Pesticide Load (PL) makes it possible for farmers to choose the least harmful fungicides and substitute between products which have an equally good efficacy profile. In practice...... been introduced as the basis for a new tax system for pesticides from 1 July 2013, replacing the old value based tax. The Government has asked for a 40% reduction in the PL per ha by 2015, based on substitutions to less harmfull products. As certain pesticide groups will be favoured by the new tax...

  20. Amelioration of irradiation injury to Florida grapefruit by pretreatment with vapor heat or fungicides

    International Nuclear Information System (INIS)

    Miller, W.R.; McDonald, R.E.

    1998-01-01

    Grapefruit shipped to certain markets must be certified free of Caribbean fruit fly (Anastrepha suspensa Loew) (CFF) infestation. Low-dose irradiation is effective for the control of CFF by sterilization. This treatment is expected to be approved for industry usage in the near future. 'Marsh' grapefruit (Citrus paradisi Macf.) was treated with vapor heat (2 hours at 38 degrees C), and fungicidal treatments of thiabendazole (TBZ) (4 gm.L-1) and TBZ (1 gm.L-1) plus imazalil (1 gm.L-1) prior to irradiation at 0.5 or 1.0 kGy. Vapor heat reduced the severity and incidence of peel injury by approximately 50% without adversely affecting other quality attributes. The fungicide did not reduce peel injury. The use of vapor heat before low-dose irradiation quarantine treatment of grapefruit may ameliorate or eliminate peel injury caused by irradiation

  1. Fungicidal control of Lophodermium seditiosum on Pinus sylvestris seedlings in Swedish forest nurseries

    Energy Technology Data Exchange (ETDEWEB)

    Stenstroem, Elna [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology; Arvidsson, Bernt [Svenska Skogsplantor AB, Joenkoeping (Sweden)

    2001-07-01

    During the 1990s, there were serious outbreaks of the pathogen Lophodermium seditiosum on pine seedlings in Swedish forest nurseries, even though the seedlings had been treated with the fungicide propiconazole. The present experiment was carried out to evaluate two other fungicides, fluazinam and azoxystrobin, as possible alternatives to propiconazole. In the tests, which were all carried out in the same forest nursery, seedlings were treated with either propiconazole, fluazinam. or azoxystrobin, and the proportion of needles with ascocarps of L. seditiosum and the number of ascocarps per needle were recorded over the following 2 yrs. Seedlings treated with azoxystrobin already appeared healthier than control seedlings in September of the first year, and by November all azoxystrobin-treated seedlings had fewer ascocarps per needle compared with control seedlings. In autumn of the second year, there were no ascocarps on seedlings treated with fluazinam or azoxystrobin, whereas seedlings treated with propiconazole had similar numbers of ascocarps to non-treated control seedlings.

  2. Translocation and metabolism of the fungicide Metalaxyl in rangpur lime seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Musumeci, M.R.; Ruegg, E.F. (Instituto Biologico, Sao Paulo (Brazil). Centro de Radioisotopos)

    1984-08-01

    The application of /sup 14/C-metalaxyl to leaves of two and six month-old Rangpur lime (Citrus limonia Osb.) seedlings is studied. In a basal foliar application, 85% of the fungicide remained in the applied leaves, though translocation was verified to upper leaves, stems and roots. When metalaxyl was applied in upper leaves only traces of radiocarbon were detected in roots and stems. After 30 days in the two-and six-month old plants, 70% of the radiocarbon corresponded to the applied fungicide Metalaxyl was degraded in leave tissues to N-(2-methoxyacetil)-N-(2,6-xylyl)-DL-alanine and two others unidentified metabolites. Polar compounds were also detected. Only 1.5% of the radiocarbon was detected as bound residue, not extracted by the acetone extraction.

  3. Translocation and metabolism of the fungicide Metalaxyl in rangpur lime seedlings

    International Nuclear Information System (INIS)

    Musumeci, M.R.; Ruegg, E.F.

    1984-01-01

    The application of 14 C-metalaxyl to leaves of two and six month-old Rangpur lime (Citrus limonia Osb.) seedlings is studied. In a basal foliar application, 85% of the fungicide remained in the applied leaves, though translocation was verified to upper leaves, stems and roots. When metalaxyl was applied in upper leaves only traces of radiocarbon were detected in roots and stems. After 30 days in the two-and six-month old plants, 70% of the radiocarbon corresponded to the applied fungicide Metalaxyl was degraded in leave tissues to N-(2-methoxyacetil)-N-(2,6-xylyl)-DL-alanine and two others unidentified metabolites. Polar compounds were also detected. Only 1.5% of the radiocarbon was detected as bound residue, not extracted by the acetone extraction. (Author) [pt

  4. The effect of stereochemistry on the biological activity of natural phytotoxins, fungicides, insecticides and herbicides.

    Science.gov (United States)

    Evidente, Antonio; Cimmino, Alessio; Andolfi, Anna

    2013-02-01

    Phytotoxins are secondary microbial metabolites that play an essential role in the development of disease symptoms induced by fungi on host plants. Although phytotoxins can cause extensive-and in some cases devastating-damage to agricultural crops, they can also represent an important tool to develop natural herbicides when produced by fungi and plants to inhibit the growth and spread of weeds. An alternative strategy to biologically control parasitic plants is based on the use of plant and fungal metabolites, which stimulate seed germination in the absence of the host plant. Nontoxigenic fungi also produce bioactive metabolites with potential fungicide and insecticide activity, and could be applied for crop protection. All these metabolites represent important tools to develop eco-friendly pesticides. This review deals with the relationships between the biological activity of some phytotoxins, seed germination stimulants, fungicides and insecticides, and their stereochemistry. Copyright © 2012 Wiley Periodicals, Inc.

  5. Preliminary Trials on Treatment of Esca-Infected Grapevines with Trunk Injection of Fungicides

    Directory of Open Access Journals (Sweden)

    T. Dula

    2007-04-01

    Full Text Available An increase in trunk diseases (due to esca, Agrobacterium, rugose wood virus, leaf roll viruses, phytoplasma etc. leading to young vines death is a very serious worry in vineyards in Hungary, as it is in other countries. In response to a demand expressed by grapevine growers, a method was tested for the direct treatment of pathogens in wood tissue. An experiment based on trunk injection was carried out in an esca infected vineyard. The various fungicides (propiconazole, difenoconazole, thiabendazole; propiconazole+ thiabendazole were injected into the trunk before the beginning of the xylem sap flow at high pressure. As a result the number of symptomatic plants was decreased, and the vigour of the plants was not impaired by the fungicide ingredients. The combination difenoconazole+ thiabendazole showed the best result.

  6. In vitro and in vivo screening of azole fungicides for antiandrogenic effects

    DEFF Research Database (Denmark)

    Taxvig, Camilla; Vinggaard, Anne; Hass, Ulla

    signs of feminization of the male offspring were investigated. Tebuconazole caused an increase in testicular 17alfa-hydroxyprogesterone and progesterone levels, and a decrease in testosterone levels in male fetuses. Epoxiconazole had no effect on any of the mesured hormonelevels. Furthermore...... and antiandrogenic effects both in vitro and in vivo. Two other azole fungicides, tebuconazole and epoxiconazole, have now been investigated for antiandrogenic effects in vitro and in vivo as well. The fungicides were screened in two well-established cell assays, including testing for agonistic and antagonistic...... effects on AR in transfected CHO cells, using an AR reporter gene assay. The compounds were also analyzed for effects on steroidogenesis in H295R cells, a human adrenocorticocarcinoma cell line, used to detect effects on steroid production. In vitro tebuconazole and epoxiconazole proved to be antagonists...

  7. Foliar Application of the Fungicide Pyraclostrobin Reduced Bacterial Spot Disease of Pepper

    Directory of Open Access Journals (Sweden)

    Beom Ryong Kang

    2018-03-01

    Full Text Available Pyraclostrobin is a broad-spectrum fungicide that inhibits mitochondrial respiration. However, it may also induce systemic resistance effective against bacterial and viral diseases. In this study, we evaluated whether pyraclostrobin enhanced resistance against the bacterial spot pathogen, Xanthomonas euvesicatora on pepper (Capsicum annuum. Although pyraclostrobin alone did not suppressed the in vitro growth of X. euvesicatoria, disease severity in pepper was significantly lower by 69% after treatments with pyraclostrobin alone. A combination of pyraclostrobin with streptomycin reduced disease by over 90% that of the control plants. The preventive control of the pyraclostrobin against bacterial spot was required application 1-3 days before pathogen inoculation. Our findings suggest that the fungicide pyraclostrobin can be used with a chemical pesticide to control bacterial leaf spot diseases in pepper.

  8. Corn silage from corn treated with foliar fungicide and performance of Holstein cows.

    Science.gov (United States)

    Haerr, K J; Lopes, N M; Pereira, M N; Fellows, G M; Cardoso, F C

    2015-12-01

    Foliar fungicide application to corn plants is used in corn aimed for corn silage in the dairy industry, but questions regarding frequency of application and its effect on corn silage quality and feed conversion when fed to dairy cows remain prevalent. The objective of this study was to evaluate the effects of various foliar fungicide applications to corn on dry matter intake (DMI), milk production, and milk composition when fed to dairy cows. Sixty-four Holstein cows with parity 2.5±1.5, 653±80kg of body weight, and 161±51d in milk were blocked and randomly assigned to 1 of 4 corn silage treatments (total mixed ration with 35% of the dry matter as corn silage). Treatments were as follows: control (CON), corn silage with no applications of foliar fungicide; treatment 1 (1X), corn silage from corn that received 1 application of pyraclostrobin (PYR) foliar fungicide (Headline; BASF Corp.) at corn vegetative stage 5; treatment 2 (2X), corn silage from corn that received the same application as 1X plus another application of a mixture of PYR and metconazole (Headline AMP; BASF Corp.) at corn reproductive stage 1 ("silking"); and treatment 3 (3X), corn silage from corn that received the same applications as 2X as well as a third application of PYR and metconazole at reproductive stage 3 ("milky kernel"). Corn was harvested at about 32% dry matter and 3/4 milk line stage of kernel development and ensiled for 200d. Treatments were fed to cows for 5wk, with the last week being used for statistical inferences. Week -1 was used as a covariate in the statistical analysis. Dry matter intake tended to be lower for cows fed corn silage treated with fungicide than CON (23.8, 23.0, 19.5, and 21.3kg for CON, 1X, 2X, and 3X, respectively). A linear treatment effect for DMI was observed, with DMI decreasing as foliar fungicide applications increased. Treatments CON, 1X, 2X, and 3X did not differ for milk yield (34.5, 34.5, 34.2, and 34.4kg/d, respectively); however, a trend for

  9. Detoxification of copper fungicide using EDTA-modified cellulosic ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-02-04

    Feb 4, 2009 ... Different countries or states have different laws, thus, ... fungi is due to the toxicity of copper ions in solution. A variety of copper .... initial concentration of Cu(II) ion solution, which ranged from 1400 to ..... exchange mechanism.

  10. Azole Fungicides as Synergists in the Aquatic Environment

    DEFF Research Database (Denmark)

    Bjergager, Maj-Britt Andersen

    be a reasonableapproach for non-interacting contaminants, synergizing compounds, enhancing the toxicity of others, maycompromise the predictive ability of the models. Though only rarely occurring, the phenomenon ofsynergism is of great concern, making apparently low and non-toxic contaminant concentrations apotential...

  11. Efficacy of fatty acid chemistry : candidate mold and decay fungicides

    Science.gov (United States)

    Robert Coleman; Vina Yang; Bessie Woodward; Patti Lebow; Carol Clausen

    2010-01-01

    Although organic, lipophilic acids, such as acetic, propionic, sorbic and benzoic, have a long history as preservatives in the food industry, relatively high concentrations are required and their bioactivities generally pertain to retarding microbial growth rather than eliminating pathogens. Moreover, exclusive use of organic acids such as lactic or citric acid, alone...

  12. Comparison of dielectric barrier discharge modes fungicidal effect on candida albicans growth

    International Nuclear Information System (INIS)

    Slama, J.; Kriha, V.; Fantova, V.; Julak, J.

    2013-01-01

    Filamentary and quasi-homogeneous mode of dielectric barrier discharge (DBD) was investigated as a plasma source with fungicidal effect on Candida albicans yeast inoculated on Sabouraud agar wafers. As compared with the filamentary DBD mode, the quasi-homogeneous mode had significantly better results: shorter exposition time needed for inhibiting C. albicans yeast, moreover the quasi-homogeneous mode had gentle influence on the agar surface structure.

  13. Proteomic profile of the plant-pathogenic oomycete Phytophthora capsici in response to the fungicide pyrimorph.

    Science.gov (United States)

    Pang, Zhili; Chen, Lei; Miao, Jianqiang; Wang, Zhiwen; Bulone, Vincent; Liu, Xili

    2015-09-01

    Pyrimorph is a novel fungicide from the carboxylic acid amide (CAA) family used to control plant-pathogenic oomycetes such as Phytophthora capsici. The proteomic response of P. capsici to pyrimorph was investigated using the iTRAQ technology to determine the target site of the fungicide and potential biomarker candidates of drug efficacy. A total of 1336 unique proteins were identified from the mycelium of wild-type P. capsici isolate (Hd3) and two pyrimorph-resistant mutants (R3-1 and R3-2) grown in the presence or absence of pyrimorph. Comparative analysis revealed that the three P. capsici isolates Hd3, R3-1, and R3-2 produced 163, 77, and 13 unique proteins, respectively, which exhibited altered levels of abundance in response to the pyrimorph treatment. Further investigations, using Cluster of Orthologous Groups of Proteins (COG) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis identified 35 proteins related to the mode of action of pyrimorph against P. capsici and 62 proteins involved in the stress response of P. capsici to pyrimorph. Many of the proteins with altered expression were associated with glucose and energy metabolism. Biochemical analysis using d-[U-(14) C]glucose verified the proteomics data, suggesting that the major mode of action of pyrimorph in P. capsici is the inhibition of cell wall biosynthesis. These results also illustrate that proteomics approaches are useful tools for determining the pathways targeted by novel fungicides as well as for evaluating the tolerance of plant pathogens to environmental challenges, such as the presence of fungicides. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Determination of acid dissociation constants of triazole fungicides by pressure assisted capillary electrophoresis

    Czech Academy of Sciences Publication Activity Database

    Konášová, Renáta; Jaklová Dytrtová, Jana; Kašička, Václav

    2015-01-01

    Roč. 1408, Aug 21 (2015), s. 243-249 ISSN 0021-9673 R&D Projects: GA ČR(CZ) GA13-17224S; GA ČR GP13-21409P Institutional support: RVO:61388963 Keywords : triazole fungicides * acid dissociation constant * pK(a) * capillary electrophoresis * ionic mobility Subject RIV: CB - Analytical Chemistry , Separation Impact factor: 3.926, year: 2015

  15. Temporal analysis and fungicide management strategies to control mango anthracnose epidemics in Guerrero, Mexico

    OpenAIRE

    Monteon Ojeda, Abraham; Mora Aguilera, José Antonio; Villegas Monter, Ángel; Nava Diaz, Cristian; Hernández Castro, Elías; Otero-Colina, Gabriel; Hernández Morales, Javier

    2012-01-01

    The temporal progress of anthracnose (Colletotrichum gloeosporioides) epidemics was studied in mango (Mangifera indica) orchards treated with fungicides from different chemical groups, mode of action, and application sequences in two regions of contrasting climates (sub-humid and dry tropics) in Guerrero, Mexico. Full flowering, initial setting, and 8-15mm Ø fruits were identified as critical stages for infection. Epidemics started 20-26 days after swollen buds, and maximum severity was attai...

  16. Evaluation of grapefruit seed extract as natural fungicide to control apple scab in organic apple growing

    OpenAIRE

    Trapman, Marc

    2004-01-01

    C-pro, an experimental fungicide based on grapefruit seed extract was compared to copper oxychloride for the control of apple scab in a field trial. Efficacy and possible phytotoxic effects where accessed. The C-pro formulation was analysed for possible chemical additives by HPTLC. C-pro proved tot be more effective in controlling apple scab then the standard rate of 300 gram copper oxychloride per ha, and gave a better leaf quality and less fruit skin russeting then the sta...

  17. Signum, a new fungicide with interesting properties in resistance management of fungal diseases in strawberries.

    Science.gov (United States)

    Hauke, K; Creemers, P; Brugmans, W; Van Laer, S

    2004-01-01

    Signum, a new fungicide developed by BASF, was applied during 6 successive years against fungal diseases in strawberries. The product is formulated as a water dispersible granule, containing 6.7 % pyraclostrobin and 26.7 % boscalid. Pyraclostrobin is similar in chemistry to other strobilurin fungicides like kresoxim-methyl and trifloxystrobin, registered for fruit disease control. Boscalid belongs to the class of carboxyanilides. Both components in the premix formulation combine two different biochemical modes of action in the fungal cell respiration. Therefore, this co-formulation gives a broad-spectrum activity and also a reduced resistance risk for different target pathogens. Botrytis cinerea is the most important disease on strawberry-fruits and thus the control of fruit rot is mainly focused on this fungus. In average over 6 years, Signum has not only given a very good control against Botrytis fruit rot, but it has also shown a high performance in the control of Colletotrichum. Besides, Signum provides good control of powdery mildew (Podosphaera aphanis) and limits the shift to other fruit rots like leather rot (Phytophthora cactorum and leak (Rhizopus, Mucor). The availability of several categories of fungicide families with a different mode of action gives opportunities in alternating different fungicides and is the best guarantee for a sustainable control of fruit rot in all kinds of strawberry production methods. Signum should be integrated in an overall disease management program. Trials, in which the applications of Signum were timed on disease forecasting, based on environmental factors favorable for Botrytis development, were very promising. This tool can also help in establishing the IPM-concept in the production of strawberries.

  18. Joint use of fungicides, insecticides and inoculants in the treatment of soybean seeds

    Directory of Open Access Journals (Sweden)

    Yara Cristiane Buhl Gomes

    Full Text Available ABSTRACT The interference of the joint application of pesticides with seed inoculation on the survival of Bradyrhizobium has been reported in the last years. So, the objective of this study was to evaluate the joint use of fungicides, insecticides and inoculant in the treatment of soybean seeds on various parameters of Bradyrhizobium nodulation in soybean as well as on crop productivity parameters. The experiment was conducted during the 2013/2014 crop in the experimental field of the Instituto Federal de Educação, Ciência e Tecnologia de Mato Grosso - Campo Novo do Parecis Campus. The seeds of TMG 133 RR variety were sown in pots. It was used a randomized block design in a 4 x 4 + 1 factorial, four fungicides (1: fludioxonil + metalaxyl-M, 2: carboxine + thiram, 3: difeconazole and 4: carbendazim + thiram, four insecticides (1: fipronil 250 SC, 2: thiamethoxam, 3: imidacloprid + thiodicarpe and 4: imodacloprid 600 FC and an inoculant (SEMIA 5079 and SEMIA 5080, common to all treatments, with three replications. The experiment was not repeated. The joint application of fungicide and insecticide with inoculant does not affect nodulation, foliar N content and vegetative growth of the plants as well as the masses of grains per plant and 100-grain mass. The use of the carbendazim + thiram mixed with fipronil and carbendazim + thiram mixed with imidacloprid provides less number of pods per plant and grains per plant, reflecting in reductions in the production of soybean grains. In this way, the fungicide carbendazim + thiram, regardless of the combined applied insecticide, is the most harmful to Bradyrhizobium spp.

  19. Foliar Application of the Fungicide Pyraclostrobin Reduced Bacterial Spot Disease of Pepper

    OpenAIRE

    Beom Ryong Kang; Jang Hoon Lee; Young Cheol Kim

    2018-01-01

    Pyraclostrobin is a broad-spectrum fungicide that inhibits mitochondrial respiration. However, it may also induce systemic resistance effective against bacterial and viral diseases. In this study, we evaluated whether pyraclostrobin enhanced resistance against the bacterial spot pathogen, Xanthomonas euvesicatora on pepper (Capsicum annuum). Although pyraclostrobin alone did not suppressed the in vitro growth of X. euvesicatoria, disease severity in pepper was significantly lower by 69% after...

  20. Biological characterization of fenpicoxamid, a new fungicide with utility in cereals and other crops.

    Science.gov (United States)

    Owen, W John; Yao, Chenglin; Myung, Kyung; Kemmitt, Greg; Leader, Andrew; Meyer, Kevin G; Bowling, Andrew J; Slanec, Thomas; Kramer, Vincent J

    2017-10-01

    The development of novel highly efficacious fungicides that lack cross-resistance is extremely desirable. Fenpicoxamid (Inatreq™ active) possesses these characteristics and is a member of a novel picolinamide class of fungicides derived from the antifungal natural product UK-2A. Fenpicoxamid strongly inhibited in vitro growth of several ascomycete fungi, including Zymoseptoria tritici (EC 50 , 0.051 mg L -1 ). Fenpicoxamid is converted by Z. tritici to UK-2A, a 15-fold stronger inhibitor of Z. tritici growth (EC 50 , 0.0033 mg L -1 ). Strong fungicidal activity of fenpicoxamid against driver cereal diseases was confirmed in greenhouse tests, where activity on Z. tritici and Puccinia triticina matched that of fluxapyroxad. Due to its novel target site (Q i site of the respiratory cyt bc1 complex) for the cereals market, fenpicoxamid is not cross-resistant to Z. tritici isolates resistant to strobilurin and/or azole fungicides. Across multiple European field trials Z. tritici was strongly controlled (mean, 82%) by 100 g as ha -1 applications of fenpicoxamid, which demonstrated excellent residual activity. The novel chemistry and biochemical target site of fenpicoxamid as well as its lack of cross-resistance and strong efficacy against Z. tritici and other pathogens highlight the importance of fenpicoxamid as a new tool for controlling plant pathogenic fungi. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  1. Mechanisms of action underlying the antiandrogenic effects of the fungicide prochloraz

    DEFF Research Database (Denmark)

    Laier, Peter; Metzdorff, Stine Broeng; Boberg, Julie

    2006-01-01

    The fungicide prochloraz has got multiple mechanisms of action that may influence the demasculinizing and reproductive toxic effects of the compound. In the present study, Wistar rats were dosed perinatally with prochloraz (50 and 150 mg/kg/day) from gestational day (GD) 7 to postnatal day (PND) ...... acts directly on the fetal testis to inhibit steroidogenesis and that this effect is exhibited at protein, and not at genomic, level. (c) 2005 Elsevier Inc. All rights reserved....

  2. Distribution of haemic neoplasia of soft-shelled clams in Prince Edward Island: an examination of anthropogenic factors and effects of experimental fungicide exposure.

    Science.gov (United States)

    Mateo, D R; MacCallum, G S; McGladdery, S E; Davidson, J

    2016-05-01

    Haemic neoplasia was first considered a disease of concern for soft-shell clams in Prince Edward Island (PEI) when it was diagnosed as the cause of mass mortalities in 1999. The aetiology of the disease remains elusive, but has been associated with environmental degradation. In this study, a 2-year (2001-2002) geographic and seasonal survey was conducted for haemic neoplasia, using histology, in soft-shell clams from PEI. In addition, using geographic information system, the association between anthropogenic factors in the watersheds at sites affected by haemic neoplasia and the prevalence of the disease was investigated. Finally, histopathological changes were assessed in soft-shell clams experimentally exposed to four concentrations of chlorothalonil for 27 days. Haemic neoplasia could not be induced at any concentration of chlorothalonil. Clams exposed to a concentration of 1000 μg L(-1) of the fungicide, however, exhibited an LC50 of 17 days. Although this information provides additional toxicity information (LC50) for soft-shell clams, further experiments are required to assess longer term exposure to the fungicide. The highest prevalences of haemic neoplasia in PEI were found in North River and Miscouche (28.3-50.9% and 33.0-77.8%, respectively). No clear seasonal patterns were found. There was a correlation between haemic neoplasia prevalence and watersheds with a high percentage of potato acreage and forest coverage (P = 0.026 and P = 0.045, respectively), suggesting a link between anthropogenic activity and the prevalence of the disease. © 2015 John Wiley & Sons Ltd.

  3. The minimum yield in channeling

    International Nuclear Information System (INIS)

    Uguzzoni, A.; Gaertner, K.; Lulli, G.; Andersen, J.U.

    2000-01-01

    A first estimate of the minimum yield was obtained from Lindhard's theory, with the assumption of a statistical equilibrium in the transverse phase-space of channeled particles guided by a continuum axial potential. However, computer simulations have shown that this estimate should be corrected by a fairly large factor, C (approximately equal to 2.5), called the Barrett factor. We have shown earlier that the concept of a statistical equilibrium can be applied to understand this result, with the introduction of a constraint in phase-space due to planar channeling of axially channeled particles. Here we present an extended test of these ideas on the basis of computer simulation of the trajectories of 2 MeV α particles in Si. In particular, the gradual trend towards a full statistical equilibrium is studied. We also discuss the introduction of this modification of standard channeling theory into descriptions of the multiple scattering of channeled particles (dechanneling) by a master equation and show that the calculated minimum yields are in very good agreement with the results of a full computer simulation

  4. Minimum Bias Trigger in ATLAS

    International Nuclear Information System (INIS)

    Kwee, Regina

    2010-01-01

    Since the restart of the LHC in November 2009, ATLAS has collected inelastic pp collisions to perform first measurements on charged particle densities. These measurements will help to constrain various models describing phenomenologically soft parton interactions. Understanding the trigger efficiencies for different event types are therefore crucial to minimize any possible bias in the event selection. ATLAS uses two main minimum bias triggers, featuring complementary detector components and trigger levels. While a hardware based first trigger level situated in the forward regions with 2.2 < |η| < 3.8 has been proven to select pp-collisions very efficiently, the Inner Detector based minimum bias trigger uses a random seed on filled bunches and central tracking detectors for the event selection. Both triggers were essential for the analysis of kinematic spectra of charged particles. Their performance and trigger efficiency measurements as well as studies on possible bias sources will be presented. We also highlight the advantage of these triggers for particle correlation analyses. (author)

  5. Late Blight of Potato (Phytophthora infestans I: Fungicides Application and Associated Challenges

    Directory of Open Access Journals (Sweden)

    Abdul Majeed

    2017-03-01

    Full Text Available Potato (Solanum tuberosum L. has been remained an important agricultural crop in resolving global food issues through decades. The crop has experienced enormous growth in terms of production throughout the world in recent decades because of improvement in agricultural mechanization, fertilizers application and irrigation practices. Nevertheless, a significant proportion of this valuable crop is still vulnerable to losses due to prevalence of different viral, bacterial, fungal and nematodes infestations. Late blight, caused by Phytophthora infestans (Mont. de Bary, is one of the most threatening pathogenic diseases which not only results in direct crop losses but also cause farmers to embrace huge monetary expenses for disease control and preventive measures. The disease is well known for notorious ‘Irish Famine’ which resulted in drop of Irish population by more than 20% as result of hunger and potato starvation. Globally, annual losses of crop and money spend on fungicides for late blight control exceeds one trillion US dollars. This paper reviews the significance of late blight of potato and controlling strategies adopted for minimizing yield losses incurred by this disease by the use of synthetic fungicides. Advantages and disadvantages of fungicides application are discussed.

  6. Retention of copper originating from different fungicides in contrasting soil types.

    Science.gov (United States)

    Komárek, Michael; Vanek, Ales; Chrastný, Vladislav; Száková, Jirina; Kubová, Karolina; Drahota, Petr; Balík, Jirí

    2009-07-30

    This work described the retention of Cu from two different commonly used pesticides, the Bordeaux mixture (CuSO(4)+Ca(OH)(2)) and Cu-oxychloride (3Cu(OH)(2).CuCl(2)), and from Cu(NO(3))(2) in contrasting soil types (Leptosol, Chernozem, Cambisol). Thermodynamic modeling showed that Cu speciation was similar in all fungicide solutions. However, the retention of Cu differed with the fungicide used (maximum retention from the Bordeaux mixture) which indicates that different retention processes occurred in the studied soils. The suggested mechanisms include: specific and non-specific adsorption (especially on soil organic matter), precipitation of newly formed phases, such as CuO, Cu(OH)(2), Cu(2)(OH)(3)NO(3), CuCO(3)/Cu(2)(OH)(2)CO(3) and in the case of the Bordeaux mixture, precipitation of various Cu-hydroxysulfates. These phases were identified by the speciation model. The retention of fungicide-derived Cu in the studied soil types followed well the Freundlich isotherm and was directly controlled by the chemical form of Cu. This fact should be taken into account for both environmental and practical applications.

  7. Retention of copper originating from different fungicides in contrasting soil types

    Energy Technology Data Exchange (ETDEWEB)

    Komarek, Michael, E-mail: komarek@af.czu.cz [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic); Vanek, Ales [Department of Soil Science and Soil Protection, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic); Chrastny, Vladislav [Department of Applied Chemistry, University of South Bohemia, Studentska 13, 370 05, Ceske Budejovice (Czech Republic); Szakova, Jirina; Kubova, Karolina [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic); Drahota, Petr [Institute of Geochemistry, Mineralogy and Mineral Resources, Charles University Prague, Albertov 6, 128 43, Prague 2 (Czech Republic); Balik, Jiri [Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences Prague, Kamycka 129, 165 21, Prague 6 (Czech Republic)

    2009-07-30

    This work described the retention of Cu from two different commonly used pesticides, the Bordeaux mixture (CuSO{sub 4} + Ca(OH){sub 2}) and Cu-oxychloride (3Cu(OH){sub 2}.CuCl{sub 2}), and from Cu(NO{sub 3}){sub 2} in contrasting soil types (Leptosol, Chernozem, Cambisol). Thermodynamic modeling showed that Cu speciation was similar in all fungicide solutions. However, the retention of Cu differed with the fungicide used (maximum retention from the Bordeaux mixture) which indicates that different retention processes occurred in the studied soils. The suggested mechanisms include: specific and non-specific adsorption (especially on soil organic matter), precipitation of newly formed phases, such as CuO, Cu(OH){sub 2}, Cu{sub 2}(OH){sub 3}NO{sub 3}, CuCO{sub 3}/Cu{sub 2}(OH){sub 2}CO{sub 3} and in the case of the Bordeaux mixture, precipitation of various Cu-hydroxysulfates. These phases were identified by the speciation model. The retention of fungicide-derived Cu in the studied soil types followed well the Freundlich isotherm and was directly controlled by the chemical form of Cu. This fact should be taken into account for both environmental and practical applications.

  8. Fungicides transport in runoff from vineyard plot and catchment: contribution of non-target areas.

    Science.gov (United States)

    Lefrancq, Marie; Payraudeau, Sylvain; García Verdú, Antonio Joaquín; Maillard, Elodie; Millet, Maurice; Imfeld, Gwenaël

    2014-04-01

    Surface runoff and erosion during the course of rainfall events are major processes of pesticides transport from agricultural land to aquatic ecosystem. These processes are generally evaluated either at the plot or the catchment scale. Here, we compared at both scales the transport and partitioning in runoff water of two widely used fungicides, i.e., kresoxim-methyl (KM) and cyazofamid (CY). The objective was to evaluate the relationship between fungicides runoff from the plot and from the vineyard catchment. The results show that seasonal exports for KM and CY at the catchment were larger than those obtained at the plot. This underlines that non-target areas within the catchment largely contribute to the overall load of runoff-associated fungicides. Estimations show that 85 and 62 % of the loads observed for KM and CY at the catchment outlet cannot be explained by the vineyard plots. However, the partitioning of KM and CY between three fractions, i.e., the suspended solids (>0.7 μm) and two dissolved fractions (i.e., between 0.22 and 0.7 µm and plot scales enable to evaluate the sources areas of pesticide off-site transport.

  9. Influence of fungicides on occurence of Fusarium spp. and other stem base diseases on winter wheat

    Directory of Open Access Journals (Sweden)

    Václav Sklenář

    2008-01-01

    Full Text Available From 1999 to 2004 the occurence of fungi: Pseudocercosporella herpotrichoides (Fron. and Fusarium spp. was evaluated in small plot field trials on seven varieties of winter wheat. The efficacy of fungicide protection against stem base diseases and influence on yields was monitored in field conditions in Velká Bystřice near Olomouc.For diagnostic of casual fungi two methods were used: 1. Method of coloring mycelium in stems, 2. Method of cultivation of mycelim on agar.Results from detection of casual fungi are following: Pseudocercosporella herpotrichoides (Fron., Fusarium culmorum (W. G. Sm. Sacc. and Fusarium graminearum Schwabe.For high efficacy of protection against roots and stem base disease the following fungicide variants should be applied: Sportak Alpha 1.5 l . ha−1 (BBCH 30/Cerelux Plus 0.7 l . ha−1 (BBCH 51, Sportak HF 1 l . ha−1 (BBCH 30/Cerelux Plus 0.7 l . ha−1, Alert S 1.0 l . ha−1 (BBCH 30/Cerelux Plus 0.7 l . ha−1 (BBCH 51. The application of fungicides positively influenced yields. Yield increased at average by10–20 % after the aplication but the rise in yields was not in total correlation with the efficacy. These results can be possibly used in the system of integral control of winter wheat against stem base disease in wheat.

  10. Application of Fungicides and Microalgal Phenolic Extracts for the Direct Control of Fumonisin Contamination in Maize.

    Science.gov (United States)

    Scaglioni, Priscila Tessmer; Blandino, Massimo; Scarpino, Valentina; Giordano, Debora; Testa, Giulio; Badiale-Furlong, Eliana

    2018-05-16

    Fungicides and, for the first time, microalgal phenolic extracts (MPE) from Spirulina sp. and Nannochloropsis sp. were applied on maize culture media under field conditions to evaluate their ability to minimize Fusarium species development and fumonisin production. An in vitro assay against F. verticillioides was carried out using maize grains as the culture medium. An open-field experiment was carried out in Northwest Italy under natural infection conditions. The compared treatments were factorial combinations of two insecticide treatments (an untreated control and pyrethroid, used against European Corn Borer), four antifungal treatments (an untreated control, MPE from Spirulina sp., MPE from Nannochloropsis sp., and a synthetic fungicide), and two timings of the application of the antifungal compounds (at maize flowering and at the milk stage). The MPE compounds were capable of inhibiting fumonisin production in vitro more efficiently than tebuconazole. Insecticide application reduced the infection by Fusarium species and subsequent fumonisin contamination. However, fumonisins in maize fields were not significantly controlled by either fungicide or MPE application.

  11. Fungicide sensitivity of Trichoderma spp. from Agaricus bisporus farms in Serbia.

    Science.gov (United States)

    Kosanović, Dejana; Potočnik, Ivana; Vukojević, Jelena; Stajić, Mirjana; Rekanović, Emil; Stepanović, Miloš; Todorović, Biljana

    2015-01-01

    Trichoderma species, the causal agents of green mould disease, induce great losses in Agaricus bisporus farms. Fungicides are widely used to control mushroom diseases although green mould control is encumbered with difficulties. The aims of this study were, therefore, to research in vitro toxicity of several commercial fungicides to Trichoderma isolates originating from Serbian and Bosnia-Herzegovina farms, and to evaluate the effects of pH and light on their growth. The majority of isolates demonstrated optimal growth at pH 5.0, and the rest at pH 6.0. A few isolates also grew well at pH 7. The weakest mycelial growth was noted at pH 8.0-9.0. Generally, light had an inhibitory effect on the growth of tested isolates. The isolates showed the highest susceptibility to chlorothalonil and carbendazim (ED50 less than 1 mg L(-1)), and were less sensitive to iprodione (ED50 ranged 0.84-6.72 mg L(-1)), weakly resistant to thiophanate-methyl (ED50 = 3.75-24.13 mg L(-1)), and resistant to trifloxystrobin (ED50 = 10.25-178.23 mg L(-1)). Considering the toxicity of fungicides to A. bisporus, carbendazim showed the best selective toxicity (0.02), iprodione and chlorothalonil moderate (0.16), and thiophanate-methyl the lowest (1.24), while trifloxystrobin toxicity to A. bisporus was not tested because of its inefficiency against Trichoderma isolates.

  12. Retention of copper originating from different fungicides in contrasting soil types

    International Nuclear Information System (INIS)

    Komarek, Michael; Vanek, Ales; Chrastny, Vladislav; Szakova, Jirina; Kubova, Karolina; Drahota, Petr; Balik, Jiri

    2009-01-01

    This work described the retention of Cu from two different commonly used pesticides, the Bordeaux mixture (CuSO 4 + Ca(OH) 2 ) and Cu-oxychloride (3Cu(OH) 2 .CuCl 2 ), and from Cu(NO 3 ) 2 in contrasting soil types (Leptosol, Chernozem, Cambisol). Thermodynamic modeling showed that Cu speciation was similar in all fungicide solutions. However, the retention of Cu differed with the fungicide used (maximum retention from the Bordeaux mixture) which indicates that different retention processes occurred in the studied soils. The suggested mechanisms include: specific and non-specific adsorption (especially on soil organic matter), precipitation of newly formed phases, such as CuO, Cu(OH) 2 , Cu 2 (OH) 3 NO 3 , CuCO 3 /Cu 2 (OH) 2 CO 3 and in the case of the Bordeaux mixture, precipitation of various Cu-hydroxysulfates. These phases were identified by the speciation model. The retention of fungicide-derived Cu in the studied soil types followed well the Freundlich isotherm and was directly controlled by the chemical form of Cu. This fact should be taken into account for both environmental and practical applications.

  13. Effect of foliar fertilizer and fungicidal protection against leaf spot diseases on winter wheat

    Directory of Open Access Journals (Sweden)

    Agnieszka Mączyńska

    2012-12-01

    Full Text Available Field experiments were carried out in the seasons 2000/2001 and 2001/2002 in Plant Protection Institute, Sooenicowice Branch to assess the influence of foliar fertilizers such as Ekolist PK 1, Ekolist Mg, Mikrosol Z and Urea on healthiness of winter wheat. Foliar fertilizers were mixed with fungicides. The fungicides were applied at full or half recommended doses. The effect of the disease on wheat leaves was evaluated three times in each vegetation season. Remaining green leaf area (GLA of leaves was also determined. GLA of the leaves F-1 was not significantly different for each combination with different fertilization and different levels of chemical treatment. The application of foliar fertilizer only had no effect on green leaf area (GLA. The results indicate that foliar fertilization of all experimental plots improved leaf condition and therefore halted the development of wheat leaf diseases. The increases of 1000 grain mass and yield was high for each plot where a fertilizer and a full or half dose of a fungicide was applied. Foliar fertilizing with no chemical control had no proven effect on studied parameters.

  14. ENVIRONMENTAL RISK ASSESSMENT OF SOME COPPER BASED FUNGICIDES ACCORDING TO THE REQUIREMENTS OF GOOD LABORATORY PRACTICE

    Directory of Open Access Journals (Sweden)

    Marga GRĂDILĂ

    2015-10-01

    Full Text Available The paper presents data demonstrating the functionality of biological systems reconstituted with aquatic organisms developed under Good Laboratory Practice testing facility within Research - Development Institute for Plant Protection Bucharest for environmental risk assessment of four fungicides based on copper, according to Good Laboratory Practice requirements. For risk assessment, according to GLP were made the following steps: Good Laboratory Practice test facility was established, we have ensured adequate space for growth, acclimatization and testing for each test species, it was installed a complex water production instalation needed to perform tests, it was achieved control system for checking environmental conditions and have developed specific operating procedures that have been accredited according to Good Laboratory Practice.The results showed that biological systems model of the Good Laboratory Practice test facility in Research - Development Institute for Plant Protection meet the requirements of Organisation for Economic Co-operation and Development Guidelines regarding GLP, and after testing copper-based fungicides in terms of acute toxicity Cyprinus carpio and to Daphnia magna revealed that three of them (copper oxychloride, copper hydroxide and copper sulphate showed ecological efficiency, ie low toxicity. Metallic copper based fungicides showed a higher toxicity, resulting in fish toxicity symptoms: sleep, sudden immersion, faded, weakness, swimming in spiral, lack of balance, breathing slow and cumbersome, spasms and mortality.

  15. Detachment of sprayed colloidal copper oxychloride-metalaxyl fungicides by a shallow water flow.

    Science.gov (United States)

    Pose-Juan, Eva; Paradelo-Pérez, Marcos; Rial-Otero, Raquel; Simal-Gándara, Jesus; López-Periago, José E

    2009-06-01

    Flow shear stress induced by rainfall promotes the loss of the pesticides sprayed on crops. Some of the factors influencing the losses of colloidal-size particulate fungicides are quantified by using a rotating shear system model. With this device it was possible to analyse the flow shear influencing washoff of a commercial fungicide formulation based on a copper oxychloride-metalaxyl mixture that was sprayed on a polypropylene surface. A factor plan with four variables, i.e. water speed and volume (both variables determining flow boundary stress in the shear device), formulation dosage and drying temperature, was set up to monitor colloid detachment. This experimental design, together with sorption experiments of metalaxyl on copper oxychloride, and the study of the dynamics of metalaxyl and copper oxychloride washoff, made it possible to prove that metalaxyl washoff from a polypropylene surface is controlled by transport in solution, whereas that of copper oxychloride occurs by particle detachment and transport of particles. Average losses for metalaxyl and copper oxychloride were, respectively, 29 and 50% of the quantity applied at the usual recommended dosage for crops. The key factors affecting losses were flow shear and the applied dosage. Empirical models using these factors provided good estimates of the percentage of fungicide loss. From the factor analysis, the main mechanism for metalaxyl loss induced by a shallow water flow is solubilisation, whereas copper loss is controlled by erosion of copper oxychloride particles.

  16. Fungicidal Drugs Induce a Common Oxidative-Damage Cellular Death Pathway

    Directory of Open Access Journals (Sweden)

    Peter Belenky

    2013-02-01

    Full Text Available Amphotericin, miconazole, and ciclopirox are antifungal agents from three different drug classes that can effectively kill planktonic yeast, yet their complete fungicidal mechanisms are not fully understood. Here, we employ a systems biology approach to identify a common oxidative-damage cellular death pathway triggered by these representative fungicides in Candida albicans and Saccharomyces cerevisiae. This mechanism utilizes a signaling cascade involving the GTPases Ras1 and Ras2 and protein kinase A, and it culminates in death through the production of toxic reactive oxygen species in a tricarboxylic-acid-cycle- and respiratory-chain-dependent manner. We also show that the metabolome of C. albicans is altered by antifungal drug treatment, exhibiting a shift from fermentation to respiration, a jump in the AMP/ATP ratio, and elevated production of sugars; this coincides with elevated mitochondrial activity. Lastly, we demonstrate that DNA damage plays a critical role in antifungal-induced cellular death and that blocking DNA-repair mechanisms potentiates fungicidal activity.

  17. Effect of Fungicide Applications on Grain Sorghum (Sorghum bicolor L. Growth and Yield

    Directory of Open Access Journals (Sweden)

    Dan D. Fromme

    2017-01-01

    Full Text Available Field studies were conducted in the upper Texas Gulf Coast and in central Louisiana during the 2013 through 2015 growing seasons to evaluate the effects of fungicides on grain sorghum growth and development when disease pressure was low or nonexistent. Azoxystrobin and flutriafol at 1.0 L/ha and pyraclostrobin at 0.78 L/ha were applied to the plants of two grain sorghum hybrids (DKS 54-00, DKS 53-67 at 25% bloom and compared with the nontreated check for leaf chlorophyll content, leaf temperature, and plant lodging during the growing season as well as grain mold, test weight, yield, and nitrogen and protein content of the harvested grain. The application of a fungicide had no effect on any of the variables tested with grain sorghum hybrid responses noted. DKS 53-67 produced higher yield, greater test weight, higher percent protein, and N than DKS 54-00. Results of this study indicate that the application of a fungicide when little or no disease is present does not promote overall plant health or increase yield.

  18. Assessment of Total Risk on Non-Target Organisms in Fungicide Application for Agricultural Sustainability

    Directory of Open Access Journals (Sweden)

    Ali Musa Bozdogan

    2014-02-01

    Full Text Available In Turkey, in 2010, the amount of pesticide (active ingredient; a.i. used in agriculture was about 23,000 metric tons, of which approximately 32% was fungicides. In 2012, 14 a.i. were used for fungus control in wheat cultivation areas in Adana province, Turkey. These a.i. were: azoxystrobin, carbendazim, difenoconazole, epoxiconazole, fluquinconazole, prochloraz, propiconazole, prothioconazole, pyraclostrobin, spiroxamine, tebuconazole, thiophanate-methyl, triadimenol, and trifloxystrobin. In this study, the potential risk of a.i. on non-target organisms in fungicide application of wheat cultivation was assessed by The Pesticide Occupational and Environmental Risk (POCER indicators. In this study, the highest human health risk was for fluquinconazole (Exceedence Factor (EF 1.798 for human health, whereas the fungicide with the highest environmental risk was propiconazole (EF 2.000 for the environment. For non-target organisms, the highest potential risk was determined for propiconazole when applied at 0.1250 kg a.i. ha-1 (EF 2.897. The lowest total risk was for azoxystrobin when applied at  0.0650 kg a.i. ha-1 (EF 0.625.

  19. Soybean (Glycine max L. Response to Fungicides in the Absence of Disease Pressure

    Directory of Open Access Journals (Sweden)

    W. James Grichar

    2013-01-01

    Full Text Available Field studies were conducted during the 2010 and 2011 growing seasons along the Texas Upper Gulf Coast region to study the effects of fungicides on soybean disease development and to evaluate the response of four soybean cultivars to prothioconazole plus trifloxystrobin and pyraclostrobin. In neither year did any soybean diseases develop enough to be an issue. Only NKS 51-T8 responded to a fungicide treatment in 2010 while HBK 5025 responded in 2011. Prothioconazole plus trifloxystrobin increased NKS 51-T8 yield by 23% in 2010 while in 2011 the yield of HBK 5025 was increased 14% over the unsprayed check. No yield response was noted with pyraclostrobin on any soybean cultivar. Only prothioconazole + trifloxystrobin applied to either NKS 51-T8 or DP5335 in 2010 resulted in a net increase in dollars per hectare over the unsprayed check of the respective cultivar. In 2011, under extremely dry conditions, all fungicides with the exception of prothioconazole + trifloxystrobin applied to HBK 5025 resulted in a net decrease in returns over the unsprayed check.

  20. Screening differentially expressed genes in an amphipod (Hyalella azteca) exposed to fungicide vinclozolin by suppression subtractive hybridization.

    Science.gov (United States)

    Wu, Yun H; Wu, Tsung M; Hong, Chwan Y; Wang, Yei S; Yen, Jui H

    2014-01-01

    Vinclozolin, a dicarboximide fungicide, is an endocrine disrupting chemical that competes with an androgenic endocrine disruptor compound. Most research has focused on the epigenetic effect of vinclozolin in humans. In terms of ecotoxicology, understanding the effect of vinclozolin on non-target organisms is important. The expression profile of a comprehensive set of genes in the amphipod Hyalella azteca exposed to vinclozolin was examined. The expressed sequence tags in low-dose vinclozolin-treated and -untreated amphipods were isolated and identified by suppression subtractive hybridization. DNA dot blotting was used to confirm the results and establish a subtracted cDNA library for comparing all differentially expressed sequences with and without vinclozolin treatment. In total, 494 differentially expressed genes, including hemocyanin, heatshock protein, cytochrome, cytochrome oxidase and NADH dehydrogenase were detected. Hemocyanin was the most abundant gene. DNA dot blotting revealed 55 genes with significant differential expression. These genes included larval serum protein 1 alpha, E3 ubiquitin-protein ligase, mitochondrial cytochrome c oxidase, mitochondrial protein, proteasome inhibitor, hemocyanin, zinc-finger-containing protein, mitochondrial NADH-ubiquinone oxidoreductase and epididymal sperm-binding protein. Vinclozolin appears to upregulate stress-related genes and hemocyanin, related to immunity. Moreover, vinclozolin downregulated NADH dehydrogenase, related to respiration. Thus, even a non-lethal concentration of vinclozolin still has an effect at the genetic level in H. azteca and presents a potential risk, especially as it would affect non-target organism hormone metabolism.

  1. Meta-analysis of yield response of hybrid field corn to foliar fungicides in the U.S. Corn Belt.

    Science.gov (United States)

    Paul, P A; Madden, L V; Bradley, C A; Robertson, A E; Munkvold, G P; Shaner, G; Wise, K A; Malvick, D K; Allen, T W; Grybauskas, A; Vincelli, P; Esker, P

    2011-09-01

    The use of foliar fungicides on field corn has increased greatly over the past 5 years in the United States in an attempt to increase yields, despite limited evidence that use of the fungicides is consistently profitable. To assess the value of using fungicides in grain corn production, random-effects meta-analyses were performed on results from foliar fungicide experiments conducted during 2002 to 2009 in 14 states across the United States to determine the mean yield response to the fungicides azoxystrobin, pyraclostrobin, propiconazole + trifloxystrobin, and propiconazole + azoxystrobin. For all fungicides, the yield difference between treated and nontreated plots was highly variable among studies. All four fungicides resulted in a significant mean yield increase relative to the nontreated plots (P pyraclostrobin (256 kg/ha), and lowest for azoxystrobin (230 kg/ha). Baseline yield (mean yield in the nontreated plots) had a significant effect on yield for propiconazole + azoxystrobin (P pyraclostrobin, propiconazole + trifloxystrobin, and propiconazole + azoxystrobin but not to azoxystrobin. Mean yield difference was generally higher in the lowest yield and higher disease severity categories than in the highest yield and lower disease categories. The probability of failing to recover the fungicide application cost (p(loss)) also was estimated for a range of grain corn prices and application costs. At the 10-year average corn grain price of $0.12/kg ($2.97/bushel) and application costs of $40 to 95/ha, p(loss) for disease severity pyraclostrobin, 0.62 to 0.93 for propiconazole + trifloxystrobin, 0.58 to 0.89 for propiconazole + azoxystrobin, and 0.91 to 0.99 for azoxystrobin. When disease severity was >5%, the corresponding probabilities were 0.36 to 95, 0.25 to 0.69, 0.25 to 0.64, and 0.37 to 0.98 for the four fungicides. In conclusion, the high p(loss) values found in most scenarios suggest that the use of these foliar fungicides is unlikely to be profitable when

  2. Experimental investigations of the minimum ignition energy and the minimum ignition temperature of inert and combustible dust cloud mixtures.

    Science.gov (United States)

    Addai, Emmanuel Kwasi; Gabel, Dieter; Krause, Ulrich

    2016-04-15

    The risks associated with dust explosions still exist in industries that either process or handle combustible dust. This explosion risk could be prevented or mitigated by applying the principle of inherent safety (moderation). This is achieved by adding an inert material to a highly combustible material in order to decrease the ignition sensitivity of the combustible dust. The presented paper deals with the experimental investigation of the influence of adding an inert dust on the minimum ignition energy and the minimum ignition temperature of the combustible/inert dust mixtures. The experimental investigation was done in two laboratory scale equipment: the Hartmann apparatus and the Godbert-Greenwald furnace for the minimum ignition energy and the minimum ignition temperature test respectively. This was achieved by mixing various amounts of three inert materials (magnesium oxide, ammonium sulphate and sand) and six combustible dusts (brown coal, lycopodium, toner, niacin, corn starch and high density polyethylene). Generally, increasing the inert materials concentration increases the minimum ignition energy as well as the minimum ignition temperatures until a threshold is reached where no ignition was obtained. The permissible range for the inert mixture to minimize the ignition risk lies between 60 to 80%. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Deprotonation and protonation of humic acids as a strategy for the technological development of pH-responsive nanoparticles with fungicidal potential.

    Science.gov (United States)

    Motta, F L; Melo, B A G; Santana, M H A

    2016-12-25

    Humic acids (HAs) are macromolecules of undefined compositions that vary with origin, the process by which they are obtained and functional groups present in their structure, such as quinones, phenols, and carboxylic acids. In addition to agriculture, there is an increased interest in HAs due to their important pharmacological effects. However, HAs are not readily soluble in water at physiological pH, which may limit their bioavailability. Although primary aggregation forms non-uniform pseudo-micelles, the presence of ionisable groups in the HA molecule makes pH an environmental stimulus for controlled aggregation and precipitation. The aim of this work was to induce HA deprotonation and protonation, without compromising their colloidal dispersion, by means of pH changes as a strategy to produce nanoparticles. Deprotonation and protonation were achieved by treating HAs with sodium hydroxide and acetic acid, respectively, at various concentrations. Non pH-treated HAs at the same concentrations were used as control. The evolution of the treatments was monitored by pH changes in bulk solutions as a function of time. At equilibrium, the conformation of the colloidal structures was characterised by the predominant mean diameter, polydispersity index and absorbance of the solutions. The zeta potential was also measured in protonation assays. Moreover, the fungicidal activity of the nanoparticles was evaluated on the mycelial growth of three fungal genera. The results showed the pH decrease or increment as a function of the balance between hydroxyl and carboxyl groups and of the diffusion rate inside the structures. Deprotonation followed by protonation produced nanosized (100-200nm), electrostatically stable (-30mV) and pH-responsive particles with a polydispersity index growth of Candida albicans in vitro, when compared with control, and the fungicidal activity was dose-dependent. No activity was observed for the deprotonated HAs nanoparticles. These results show that

  4. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-11-09

    We present a general framework and method for detection of an object in a video based on apparent motion. The object moves relative to background motion at some unknown time in the video, and the goal is to detect and segment the object as soon it moves in an online manner. Due to unreliability of motion between frames, more than two frames are needed to reliably detect the object. Our method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  5. Approximating the minimum cycle mean

    Directory of Open Access Journals (Sweden)

    Krishnendu Chatterjee

    2013-07-01

    Full Text Available We consider directed graphs where each edge is labeled with an integer weight and study the fundamental algorithmic question of computing the value of a cycle with minimum mean weight. Our contributions are twofold: (1 First we show that the algorithmic question is reducible in O(n^2 time to the problem of a logarithmic number of min-plus matrix multiplications of n-by-n matrices, where n is the number of vertices of the graph. (2 Second, when the weights are nonnegative, we present the first (1 + ε-approximation algorithm for the problem and the running time of our algorithm is ilde(O(n^ω log^3(nW/ε / ε, where O(n^ω is the time required for the classic n-by-n matrix multiplication and W is the maximum value of the weights.

  6. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-01-08

    We present a general framework and method for detection of an object in a video based on apparent motion. The object moves relative to background motion at some unknown time in the video, and the goal is to detect and segment the object as soon it moves in an online manner. Due to unreliability of motion between frames, more than two frames are needed to reliably detect the object. Our method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  7. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong; Sundaramoorthi, Ganesh

    2017-01-01

    We present a general framework and method for detection of an object in a video based on apparent motion. The object moves relative to background motion at some unknown time in the video, and the goal is to detect and segment the object as soon it moves in an online manner. Due to unreliability of motion between frames, more than two frames are needed to reliably detect the object. Our method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  8. Youth minimum wages and youth employment

    NARCIS (Netherlands)

    Marimpi, Maria; Koning, Pierre

    2018-01-01

    This paper performs a cross-country level analysis on the impact of the level of specific youth minimum wages on the labor market performance of young individuals. We use information on the use and level of youth minimum wages, as compared to the level of adult minimum wages as well as to the median

  9. Do Some Workers Have Minimum Wage Careers?

    Science.gov (United States)

    Carrington, William J.; Fallick, Bruce C.

    2001-01-01

    Most workers who begin their careers in minimum-wage jobs eventually gain more experience and move on to higher paying jobs. However, more than 8% of workers spend at least half of their first 10 working years in minimum wage jobs. Those more likely to have minimum wage careers are less educated, minorities, women with young children, and those…

  10. Does the Minimum Wage Affect Welfare Caseloads?

    Science.gov (United States)

    Page, Marianne E.; Spetz, Joanne; Millar, Jane

    2005-01-01

    Although minimum wages are advocated as a policy that will help the poor, few studies have examined their effect on poor families. This paper uses variation in minimum wages across states and over time to estimate the impact of minimum wage legislation on welfare caseloads. We find that the elasticity of the welfare caseload with respect to the…

  11. Minimum income protection in the Netherlands

    NARCIS (Netherlands)

    van Peijpe, T.

    2009-01-01

    This article offers an overview of the Dutch legal system of minimum income protection through collective bargaining, social security, and statutory minimum wages. In addition to collective agreements, the Dutch statutory minimum wage offers income protection to a small number of workers. Its

  12. Evidence of low dose effects of the antidepressant fluoxetine and the fungicide prochloraz on the behavior of the keystone freshwater invertebrate Gammarus pulex.

    Science.gov (United States)

    De Castro-Català, N; Muñoz, I; Riera, J L; Ford, A T

    2017-12-01

    In recent years, behavior-related endpoints have been proposed as rapid and reliable ecotoxicological tools for risk assessment. In particular, the use of detritivores to test the toxicity of pollutants through feeding is currently becoming a well-known method. Experiments combining feeding with other behavioral endpoints can provide relevant information about direct and indirect toxicological effects of chemicals. We carried out a feeding experiment with the shredder Gammarus pulex in order to detect indirect (through leaf conditioning) and direct effects (through water exposure) of two pollutants at environmentally relevant concentrations: the fungicide prochloraz (6 μg/L) and the antidepressant fluoxetine (100 ng/L). Prochloraz inhibited fungal growth on leaves, but it did not affect either the microbial breakdown rates or the C:N ratio of the leaves. Individuals of G. pulex that were fed with treated leaves presented lower consumption rates, not only those fed with prochloraz-treated leaves, but also those fed with fluoxetine-treated leaves, and those fed with the mixture-treated leaves. Mixed-effects models revealed that the swimming velocity of the amphipods after the experiment was modulated by the exposure to fluoxetine, and also by the exposure to prochloraz. We demonstrate that both the antidepressant and the fungicide may cause significant sublethal effects at low concentrations. The combination of behavioral endpoints together with the application of mixed models provided a useful tool for early detection of the effects of toxicity mixtures in freshwater ecosystems. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Fungicidal activity of Eucalyptus tereticornis essential oil on the pathogenic fungus Fusarium oxysporum Actividad antimicótica del aceite esencial a partir de Eucalyptus tereticornis sobre el hongo patógeno Fusarium oxysporum

    Directory of Open Access Journals (Sweden)

    Walter Murillo Arango

    2011-06-01

    Full Text Available The objective of present paper was to determine the antifungal activity of the Eucalyptus tereticornis (Myrtaceae essential oil and two fractions on the Fusarium oxysporum mushroom, a pathogen with clinical and agricultural significance. The total citronelal (44.8 % and geraniol (9.78 % essential oil had a fungicidal effect at a 3 g/L concentration and a fungicidal activity at small concentrations. The A and B fractions composed most of p-mentane-3,8-diol (18.95 % and geraniol acetate (24.34 %, respectively were more active than the total extract. The observations at microscopic level showed damages and changes in hyphae and chlamydospores, as well as a decrease in the number of conidia. The observed fungicidal activity and the morphologic damages were dependent on the concentration.El objetivo de este trabajo fue determinar la actividad antifúngica del aceite esencial de Eucalyptus tereticornis (Myrtaceae y 2 fracciones sobre el hongo Fusarium oxysporum, patógeno de importancia tanto clínica como agrícola. El aceite esencial total, compuesto principalmente por citronelal (44,8 %, citronelol (9,78 % presentó un efecto fungicida a una concentración de 3 g/L y actividad fungistática a concentraciones menores. La fracciones A y B compuestas en su mayoría por p-mentano-3,8-diol (18,95 % y acetato de citronelol (24,34 % respectivamente fueron más activas que el extracto total. Las observaciones a nivel microscópico mostraron daños y cambios en hifas y clamidosporas, así como disminución en el número de conidias. La actividad fungistática observada y los daños morfológicos fueron dependientes de la concentración.

  14. Minimum wage development in the Russian Federation

    OpenAIRE

    Bolsheva, Anna

    2012-01-01

    The aim of this paper is to analyze the effectiveness of the minimum wage policy at the national level in Russia and its impact on living standards in the country. The analysis showed that the national minimum wage in Russia does not serve its original purpose of protecting the lowest wage earners and has no substantial effect on poverty reduction. The national subsistence minimum is too low and cannot be considered an adequate criterion for the setting of the minimum wage. The minimum wage d...

  15. Split-plot fractional designs: Is minimum aberration enough?

    DEFF Research Database (Denmark)

    Kulahci, Murat; Ramirez, Jose; Tobias, Randy

    2006-01-01

    Split-plot experiments are commonly used in industry for product and process improvement. Recent articles on designing split-plot experiments concentrate on minimum aberration as the design criterion. Minimum aberration has been criticized as a design criterion for completely randomized fractional...... factorial design and alternative criteria, such as the maximum number of clear two-factor interactions, are suggested (Wu and Hamada (2000)). The need for alternatives to minimum aberration is even more acute for split-plot designs. In a standard split-plot design, there are several types of two...... for completely randomized designs. Consequently, we provide a modified version of the maximum number of clear two-factor interactions design criterion to be used for split-plot designs....

  16. Entropy concentration and the empirical coding game

    NARCIS (Netherlands)

    Grünwald, P.D.

    2008-01-01

    We give a characterization of maximum entropy/minimum relative entropy inference by providing two 'strong entropy concentration' theorems. These theorems unify and generalize Jaynes''concentration phenomenon' and Van Campenhout and Cover's 'conditional limit theorem'. The theorems characterize

  17. Minimum Delay Moving Object Detection

    KAUST Repository

    Lao, Dong

    2017-05-14

    This thesis presents a general framework and method for detection of an object in a video based on apparent motion. The object moves, at some unknown time, differently than the “background” motion, which can be induced from camera motion. The goal of proposed method is to detect and segment the object as soon it moves in an online manner. Since motion estimation can be unreliable between frames, more than two frames are needed to reliably detect the object. Observing more frames before declaring a detection may lead to a more accurate detection and segmentation, since more motion may be observed leading to a stronger motion cue. However, this leads to greater delay. The proposed method is designed to detect the object(s) with minimum delay, i.e., frames after the object moves, constraining the false alarms, defined as declarations of detection before the object moves or incorrect or inaccurate segmentation at the detection time. Experiments on a new extensive dataset for moving object detection show that our method achieves less delay for all false alarm constraints than existing state-of-the-art.

  18. Effect of the spray volume adjustment model on the efficiency of fungicides and residues in processing tomato

    Energy Technology Data Exchange (ETDEWEB)

    Ratajkiewicz, H.; Kierzek, R.; Raczkowski, M.; Hołodyńska-Kulas, A.; Łacka, A.; Wójtowicz, A.; Wachowiak, M.

    2016-11-01

    This study compared the effects of a proportionate spray volume (PSV) adjustment model and a fixed model (300 L/ha) on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont.) de Bary) (PLB) and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha) when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop. (Author)

  19. Effect of the spray volume adjustment model on the efficiency of fungicides and residues in processing tomato

    Directory of Open Access Journals (Sweden)

    Henryk Ratajkiewicz

    2016-08-01

    Full Text Available This study compared the effects of a proportionate spray volume (PSV adjustment model and a fixed model (300 L/ha on the infestation of processing tomato with potato late blight (Phytophthora infestans (Mont. de Bary (PLB and azoxystrobin and chlorothalonil residues in fruits in three consecutive seasons. The fungicides were applied in alternating system with or without two spreader adjuvants. The proportionate spray volume adjustment model was based on the number of leaves on plants and spray volume index. The modified Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS method was optimized and validated for extraction of azoxystrobin and chlorothalonil residue. Gas chromatography with a nitrogen and phosphorus detector and an electron capture detector were used for the analysis of fungicides. The results showed that higher fungicidal residues were connected with lower infestation of tomato with PLB. PSV adjustment model resulted in lower infestation of tomato than the fixed model (300 L/ha when fungicides were applied at half the dose without adjuvants. Higher expected spray interception into the tomato canopy with the PSV system was recognized as the reasons of better control of PLB. The spreader adjuvants did not have positive effect on the biological efficacy of spray volume application systems. The results suggest that PSV adjustment model can be used to determine the spray volume for fungicide application for processing tomato crop.

  20. Nanoemulsion Formulations of Fungicide Tebuconazole for Agricultural Applications

    Directory of Open Access Journals (Sweden)

    Vianney Díaz-Blancas

    2016-09-01

    Full Text Available Tebuconazole (TBZ nanoemulsions (NEs were formulated using a low energy method. TBZ composition directly affected the drop size and surface tension of the NE. Water fraction and the organic-to-surfactant-ratio (RO/S were evaluated in the range of 1–90 and 1–10 wt %, respectively. The study was carried out with an organic phase (OP consisting of an acetone/glycerol mixture containing TBZ at a concentration of 5.4 wt % and Tween 80 (TW80 as a nonionic and Agnique BL1754 (AG54 as a mixture of nonionic and anionic surfactants. The process involved a large dilution of a bicontinuous microemulsion (ME into an aqueous phase (AP. Pseudo-ternary phase diagrams of the OP//TW80//AP and OP//AG54//AP systems at T = 25 °C were determined to map ME regions; these were in the range of 0.49–0.90, 0.01–0.23, and 0.07–0.49 of OP, AP, and surfactant, respectively. Optical microscope images helped confirm ME formation and system viscosity was measured in the range of 25–147 cP. NEs with drop sizes about 9 nm and 250 nm were achieved with TW80 and AG54, respectively. An innovative low-energy method was used to develop nanopesticide TBZ formulations based on nanoemulsion (NE technology. The surface tension of the studied systems can be lowered 50% more than that of pure water. This study’s proposed low-energy NE formulations may prove useful in sustainable agriculture.