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Sample records for fungicide methyl thiophanate

  1. Biodegradation kinetics of the benzimidazole fungicide thiophanate-methyl by bacteria isolated from loamy sand soil.

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    Cycoń, Mariusz; Wójcik, Marcin; Piotrowska-Seget, Zofia

    2011-06-01

    Degradation of the fungicide thiophanate-methyl (TM) by Enterobacter sp. TDS-1 and Bacillus sp. TDS-2 isolated from sandy soil previously treated with TM was studied in mineral salt medium (MSM) and soil. Both strains were able to grow in MSM supplemented with TM (50 mg l(-1)) as the sole carbon source. Over a 16 days incubation period, 60 and 77% of the initial dose of TM were degraded by strains TDS-1 and TDS-2, respectively, and disappearance of TM was described by first-order kinetics. Medium supplementation with glucose markedly stimulated bacterial growth; while the final rate of TM degradation was reduced by 21 and 27% for strains TDS-1 and TDS-2, respectively as compared to medium with TM only. Moreover, this additional carbon source changed the TM degradation kinetics, which proceeded according to a zero-order model. This effect was linked to substrate competition and/or a strong decrease of medium pH. Isolates degraded TM (100 mg kg(-1)) in soil with rate constants of 0.186 and 0.210 day(-1), following first-order rate kinetics, and the time in which the initial TM concentration was reduced by 50% (DT50) in soils inoculated with strains TDS-1 and TDS-2 were 6.3 and 5.1 days, respectively. Analysis of TM degradation products in soil showed that the tested strains may have the potential to transform carbendazim (MBC) to 2-aminobenzimidazole (2-AB), and may be useful for a bioremediation of MBC-polluted soils.

  2. In vitro Sensitivity of the Mushroom Pathogen Cladobotryum spp. to Thiophanate-Methyl and Different Carbendazim Formulations

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    Ivana Potočnik

    2008-01-01

    Full Text Available A survey of in vitro sensitivity of 13 isolates of the mushroom pathogen Cladobotryum spp. to the fungicides thiophanate-methyl, carbendazim, cyproconazole+carbendazim and flusilazole+carbendazim was undertaken. The isolates were collected from diseased fruitingbodies of Agaricus bisporus sampled from mushroom farms in Serbia over the period 2003-2006. Sensitivity to the selected fungicides was tested and all isolates were found to be highly sensitive to carbendazim (EC50 = 0.24 - 2.92 mg l-1, cyproconazole+carbendazim(EC50 = 0.33 - 1.82 mg l-1 and especially to flusilazole+carbendazim (EC50 = 0.02 - 0.11 mg l-1. All the isolates tested were weakly resistant to thiophanate-methyl and had EC50 values in the region of 6.53 to 12.09 mg l-1.

  3. Behavior of Thiophanate Methyl and Propiconazole in Grape and Mango Fruits Under the Egyptian Field Conditions.

    Science.gov (United States)

    Soliman, Amira Sh; Helmy, Rania M A; Nasr, Islam N; Abbas, Mohamed S; Mahmoud, Hend A; Jiang, Wayne

    2017-05-01

    This research aims at determining residues of thiophanate methyl and propiconazole in grape and mango fruits as an indication for their persistence in this environmental compartment. Fruit extracts were analyzed for thiophanate methyl using High Performance Liquid Chromatography and using Gas Chromatography Electron Capture Detector (GC/ECD), respectively. The results indicated that propiconazole had a less environmental impact since propiconazole had shorter residue half-lives which were 1.24 and 1.19 days in grape and mango fruits, respectively, while thiophanate methyl had half-lives of 2.49 and 2.64 days in mango and grape, respectively. The degradation rates of propiconazole in grape and mango fruits did not change significantly and neither did those of thiophanate methyl. According to the maximum residue level, the pre-harvest intervals of propiconazole were set to be 3 and 7 days for grape and mango fruits, respectively, and the pre-harvest intervals for thiophanate methyl were 15 days for both grape and mango fruits. Propiconazole was generally considered to be less hazardous to humans and will leave the environment less altered because of its faster degradation than that of thiophanate methyl.

  4. Control of Radopholus similis in anthurium with spinosad, spirotetramat, and thiophanate-methyl

    Science.gov (United States)

    Radopholus similis is an endoparasitic migratory nematode that causes anthurium decline. Our objective was to evaluate the efficacy of spinosad, spirotetramat, and thiophanate-methyl for the control of R. similis in anthurium. Plants were weighed, transplanted into 15-cm-d clay pots filled with cin...

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

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    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.

  6. 长期施药果园中的苹果轮纹病菌对戊唑醇和甲基硫菌灵的敏感性%Susceptibility of Botryosphaeria dothidea to tebuconazole and thiophanate-methyl

    Institute of Scientific and Technical Information of China (English)

    安久栋; 国立耘; 朱小琼; 宋月凤

    2016-01-01

    In order to monitor the susceptibility of Botryosphaeria dothidea to tebuconazole and thiophanate-meth-yl in orchards with long history of using these two fungicides,the susceptibility of B .dothidea isolates collected from represented orchards to these two fungicides was determined based on mycelium growth rate.The results showed that the EC50 values of tebuconazole against 69 isolates collected from Yantai,Shandong Province with ap-plication of tebuconazole for 1-2 times each year for 5 years ranged from 0.017 4 to 0.114 3 μg/mL with no ap-peared resistant sub-populations.The EC50 values of thiophanate-methyl against 34 isolates collected from Chang-ping District,Beijing with application of thiophanate-methyl for 2 times each year for 10 years ranged from 0.846 4 to 4.677 4 μg/mL with no appeared resistant sub-populations.The maximum and minimum values were 1.19 and 6.59 times of the reported susceptible baseline,respectively.%为了监测果园中苹果轮纹病菌对戊唑醇和甲基硫菌灵敏感水平的变化,采用菌丝生长速率法测定了采集自山东烟台地区和北京市昌平区,有较长施药史苹果园中的苹果轮纹病菌对戊唑醇和甲基硫菌灵的敏感性。结果表明:戊唑醇对连续施用戊唑醇5年、每年施药1~2次的果园中苹果轮纹病菌的 EC50为0.0174~0.1143μg/mL,即该类果园中苹果轮纹病菌对此药的敏感性仍然保持在较高水平,与野生菌株的敏感性非常接近,没有出现敏感性分化的抗药亚群体;甲基硫菌灵对连续施用甲基硫菌灵10年、每年施药2次的果园中苹果轮纹病菌的 EC50为0.8464~4.6774μg/mL,果园中苹果轮纹病菌与野生菌株相比 EC50平均值约上升3.15倍,最低值和最高值分别是已报道敏感性基线的1.19倍和6.59倍,没有出现敏感性发生显著分化的抗药性亚群体。

  7. LC-MS/MS法测定浓缩果汁中2-氨基苯并咪唑、多菌灵、噻菌灵、甲基硫菌灵的残留量%Determination of 2-aminobenzimidazole,carbendazim,triabendazole,thiophanate-methyl in concentrated fruit juice by LC-MS/MS

    Institute of Scientific and Technical Information of China (English)

    黄文雯; 刘晓松; 郑玲; 宁恩创

    2012-01-01

    A liquid chromatography with electrospray tandem mass spectrometry method was developed for quantitative determination of 2-aminobenzimidazole,carbendazim,triabendazole,thiophanate-methyl in concentrated fruit juice. Apple,mango,pineapple,pear,orange,lychee,passion fruit juice concentrate were selected as samples. The samples were extracted by acetonitrile and purified by PSA column. With methanol-10mmol/L ammonium acetate (containing 0.1% volume concentration of formic acid) as mobile phase gradient elution,extractions of samples were separated by ZORBAX Eclipse XDB-C18 column and detected by electrospray tandem mass spectrometry with ESI+ and multiple reaction monitoring(MRM) modes. Results showed that the mean recoveries ranged from 70.3%~109.8% with relative standard deviations in the range of 0.1%~10.9% when the spiked concentrations of 2-amino-benzimidazole were 2,4,20μg/kg and thiophene benomyl,carbendazim,thiophanate-methyl were 1,2,10μg/kg respectively. And the limits of detections of 2-amino-benzimidazole,carbendazim,thiabendazole,thiophanate-methyl were 2,1,1,1μg/kg. This method can be used to accurately and efficiently detect these four fungicides residues in concentrated fruit juice so it can be an important measure to monitor and control the quality of concentrated fruit juice.%建立了同时测定浓缩果汁中2-氨基苯并咪唑、噻菌灵、多菌灵、甲基硫菌灵的LC-MS/MS检测法。选取苹果、芒果、菠萝、梨、橙、荔枝、西番莲7种浓缩果汁进行了研究,样品采用乙腈提取,经PSA(乙二胺基N-丙基柱)柱净化后用LC-MS/MS测定。色谱条件是以甲醇-10mmol/L的乙酸铵(含0.1%体积浓度的甲酸)为流动相进行梯度洗脱,待测物经ZORBAX Eclipse XDB-C18柱分离,最后用电喷雾正离子(ESI+)和多反应监测模式(MRM)进行MS测定。结果表明,当2-氨基苯并咪唑添加水平为2、4、20μg/kg,噻菌灵、多菌灵、甲基硫菌灵添加水平为1、2、10

  8. Influência das variáveis ambientais no progresso da antracnose do feijoeiro e eficiência de tiofanato metílico + clorotalonil no controle da doença Influence of the environmental variables in the progress of anthracnose of bean and efficiency of thiophanate methyl + chlorothalonil in the control of the disease

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    Alvanir Garcia

    2007-12-01

    Full Text Available Em Minas Gerais a antracnose destaca-se como uma das principais doenças foliares do feijoeiro comum, pela sua ocorrência em diversas épocas de plantio e redução na produção. No presente trabalho avaliou-se a ocorrência, o progresso da doença e a eficiência do controle químico da antracnose. Foram avaliadas parcelas com e sem tratamento fungicida (Tiofanato metílico + Clorotalonil, 240 + 600g i.a./ha em cinco épocas de avaliação da doença em 24 plantios da cultivar carioca, de 04/96 à 03/97. Não se constatou a ocorrência da antracnose no período de fevereiro a março de 1997. O tratamento com fungicida resultou em menor severidade da doença e maior produção, principalmente nos meses de maior severidade dela. A severidade da doença correlacionou-se com as variáveis ambientais de temperatura máxima e mínima e umidade relativa aos 43, 57 e 71 dias após a emergência. Houve correlação negativa entre severidade da doença e produtividade do feijoeiro.In Minas Gerais the anthracnose is one of the most important leaf diseases of the common bean due to occur at various planting time and to reduce the production. The present experiment was performed aiming to evaluate occurrence, progress of the disease and the efficiency of fungicide on the control of bean anthracnose. Plots with and without fungicide treatment (Thiophanate methyl + Chlorothalonil, 240 + 600g a. i./ha were evaluated in five times of evaluation during 24 sowing times of bean cultivar Carioca, between April/96 and March/97. The occurrence of the anthracnose was not verified during february and march of 1997. Treatment with fungicide resulted in the lower disease severity and higher yield, mainly in the months of higher severity of the disease. There was significant correlation between the severity and the maximum and minimum temperature and relative humidity 43, 57 and 71 days after emergency. There was a negative correlation between severity of the disease

  9. 黄瓜和土壤中甲基硫菌灵·戊唑醇的残留分析%Residues Analysis of Thiophanate-methyl and Tebuconazole in Cucumber and Soil

    Institute of Scientific and Technical Information of China (English)

    裴欣; 王继军; 陈志永; 黄士忠

    2012-01-01

    [Methods] An analytical method was developed to extract tebuconazole and thiophanate-methyl from cucumber and soil simultaneously. The residues were extracted from samples with acetone, after salting-out by lead acetate and sodium chloride, cleaned up with dichloromethane, finally detected by GC, HPLC. [Results] The minimum detectable concentration of tebuconazole and thiophanate-methyl were 0.005, 0.01 mg/kg. The minimum detectable limit were 0.1 × 10-10, 0.29×10-9 g. The recovery rate were 88.44-96.13%, 85.33-93.86%. The variation coefficient were 1.93-4.18%, 3.51-4.68% respectively. [Conclusions] The study results indicated this method was correct and precision to meet the requirements of the residual analysis.%[方法]建立了在黄瓜及土壤中共同提取甲基硫菌灵和戊唑醇的残留分析方法.样品经丙酮提取,醋酸铅氯化钠盐析后,二氯甲烷萃取净化,最后采用气相色谱和高效液相色谱测定.[结果]戊唑醇和甲基硫菌灵在黄瓜和土壤中的最低检测质量分数分别为0.005、0.01 mg/kg;最小检出量分别为0.1×10-10、0.29×10-9 g;添加回收率分别为88.44%~96.13%、85.33%~93.86%;变异系数分别为1.93%~4.18%、3.51%~4.68%.[结论]建立的方法准确精密,能够满足农药残留分析的要求.

  10. Impact of Fungicides Used for Wheat Treatment on Button Mushroom Cultivation

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    Ivana Potočnik

    2012-01-01

    Full Text Available Little information is currently available on the potential environmental risks that fungicides applied during wheat cultivation and remaining in straw may have for mushroom production. The substrate for many cultivated mushrooms is mostly based on cereal straw. This review aimed to answer the question whether residues of the fungicides commonly used in wheat production and remaining in straw could be directly or indirectly responsible for changes in yields of Agaricus bisporus. Potential chemical risks of eight fungicides (for wheat treatments for A. bisporus: mancozeb, carbendazim, thiophanate-methyl,carbendazim+cyproconazole, carbedazim+flusilasole, captan, chlorothalonil and trifloxystrobinare disscused. Only the value of maximum residue level of flusilasole and its formulation was evaluated as higher than medium effective concentration of the fungicide for A.bisporus. As a conclusion, flusilazole treatment could be a limiting factor for using straw for composting and mushroom cultivation.

  11. Field Test on Chinnese Pine Seedling Damping - off by Fungicide%油松幼苗立枯病的田间药剂防治试验

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    孙福林

    2011-01-01

    Using carbendazim, Dexon, thiophanate -methyl and ferrous sulfate et al five kinds fungicide soil sterilization and combination seedling root pouring methods for prevention and control seedling damping-off test, control effect of thiophanate-methyl was 86.2% , control effect was remarkable.%采用多菌灵、代森锰锌、敌克松、甲基硫菌灵和硫酸亚铁5种杀菌剂采用土壤消毒和苗期灌根相结合的方法,对油松苗期立枯病进行防治,甲基硫菌灵防治效果86.2%,防治效果显著。

  12. Fungicide sensitivity of Trichoderma spp. from Agaricus bisporus farms in Serbia.

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    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.

  13. Different toxicity of the strobilurin fungicides kresoxim-methyl and trifloxistrobin to Venturia inaequalis isolates from Serbia.

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    Stević, Milan; Tamaš, Nenad; Miletić, Novica; Vukša, Petar

    2015-01-01

    Sensitivity of monosporial isolates of V. inaequalis, originated from apple orchards previously exposed (commercial and experimental) and those originated from location where fungicides had never been used (wild type), to strobilurin fungicides kresoxim-methyl and trifloxistrobin was investigated in this study. The experiments were carried out in laboratory using in vitro and in vivo methods. Mycelia growth inhibition on PDA medium with kresoxim-methyl and trifloxistrobin was monitored and sensitivity parameters (EC50 values) were determined using probit analysis. The isolates sensitivity in vivo was tested on apple seedlings using inoculation method. The EC50 values were ranging from 0.066-2.033 and 0.011-0.323 µg mL(-1) for kresoxim-methyl and trifloxistrobin, respectively. The wild type of isolates showed a normal susceptibility to kresoxim-methyl and trifloxistrobin, while isolates originated from experimental and commercial orchard where those fungicides had been used extensively, showed significantly lower sensitivity to the both strobilurin fungicides. The isolate that showed the resistance to kresoxim-methyl and trifloxistrobin in vitro test, also showed reduced sensitivity in vivo test and could not been controlled satisfactory by fungicide concentrations that are commercially used, as well as by double higher, after apple seedlings inoculation.

  14. Determination of carbendazim and thiophanate-methyl in red wine by high pressure liquid chromatography-linear ion trap mass spectrometry%高压液相色谱-线性离子阱串联质谱法测定红葡萄酒中多菌灵和甲基硫菌灵

    Institute of Scientific and Technical Information of China (English)

    李鹏; 刘凯丽; 杨欣; 赵云峰; 吴永宁

    2013-01-01

      目的建立红葡萄酒中多菌灵和甲基硫菌灵残留的高压液相色谱-串联线性离子阱质谱(HPLC-LIT-MS/MS)检测方法.方法样品经过乙腈提取,在梯度洗脱程序下经CAPCELL PAK CR 1:20色谱柱分离后,采用HPLC-LIT-MS/MS,在二级质谱选择反应监测(SRM)模式进行测定.结果红葡萄酒中多菌灵和甲基硫菌灵添加水平为10、20、50μg/L时,平均回收率分别为82.5%~103.1%和93.7%~115.2%.检出限(LODs)分别为0.063μg/L和0.019μg/L,定量限(LOQs)分别为0.125μg/L和0.075μg/L.结论该方法快速简便,灵敏度高,准确度和精密度均满足痕量分析要求.%Objective To develop a method of high pressure liquid chromatography-linear ion trap mass spectrometry (HPLC-LIT-MS) for the determination of carbendazim and thiophanate-methyl in red wine. Methods Samples were ultrasonically extracted with acetonitrile, separated on a CAPCELL PAK CR 1:20 column with gradient elution and the mass spectrometric acquisition was carried out under the mode of selected reaction monitoring (SRM). Results The average recoveries of carbendazim and thiophanate-methyl in red wine at 10, 20μg/L and 50μg/L were 82.5%~103.1%and 93.7%~115.2%, respectively. The limits of detection (LODs) were 0.063 μg/L and 0.019μg/L, and the limits of quantification (LOQs) were 0.125μg/L and 0.075μg/L. Conclusion The established method is fast, simple, selective, precise and accurate, and it is suitable for quantitative and qualitative detection of carbendazim and thiophanate-methyl in red wine.

  15. Sooty blotch and flyspeck control with fungicide applications based on calendar, local IPM, and warning system

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    Piérri Spolti

    2011-07-01

    Full Text Available The objective of this work was to compare fungicide application timing for the control of sooty blotch and flyspeck (SBFS of 'Fuji' apples in Rio Grande do Sul state, Brazil. The following treatments were evaluated in two growing seasons: two warning system-based (modified version of the Brown-Sutton-Hartmann system spray of captan plus thiophanate methyl, with or without summer pruning; two calendar/rain-based spray of captan or a mixture of captan plus thiophanate methyl; fungicide spray timing based on a local integrated pest management (IPM for the control of summer diseases; and a check without spraying. Sooty blotch and flyspeck incidence over time and their severity at harvest were evaluated. The highest number of spray was required by calendar/rain-based treatments (eight and seven sprays in the sequential years. The warning system recommended five and three sprays, in the sequential years, which led to the highest SBFS control efficacy expressed by the reduced initial inoculum and disease progress rate. Summer pruning enhanced SBFS control efficacy, especially by suppressing SBFS signs which tended to be restrained to the peduncle region of the fruit. Sooty blotch and flyspeck can be managed both with calendar and the grower-based IPM practices in Brazil, but a reduced number of sprays is required when the warning system is used.

  16. Effect of microelement and chemical fungicides on biocontrol effect of Trichoderma T23

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    ZHUANG Jing-hua; GAO Zeng-gui; YANG Chang-cheng; LIU Xian; CHEN Jie

    2004-01-01

    @@ Recently there have been many reports about soil diseases controlled by Trichoderma, but few could be applied on agriculture production in large areas. T23 isolated from soil around plant roots in the field by Biopesticide Engineering Center of Shenyang Agricultural University could control effectively Cucurbits Fusarium Wilt. The effects of 9 microelements which include copper, zinc, iron, boron,molybdenum, calcium, manganese, magnesium, potassium and frequently-used chemical fungicides,such as-carbendazim, thiram, thiophanate-methyl, chlorothalonil and hymexazol on the growth and the amounts of spores of Fusarium oxysporum FJ and Trichoderma T23 were studied. The effects of those factors on control effect of T23 to melon diseases were discussed and gave basis for the screening of synergistic agents and fungicides in controlling synergistically the pathogen.

  17. Experimental and field studies with thiophanate in pigs.

    Science.gov (United States)

    Baines, D M; Dalton, S E; Eichler, D A

    1976-08-14

    Thiophanate, administered at a dosage of 50 mg per kg to artifically infected pigs, removed 96 to 99 per cent of adult Oesophagostomum spp, Hyostrongylus rubidus and Trichuris suis. Activity was also high against larval stages of these nematodes, except for 26-day-old T suis. Thiophanate also showed ovicidal and larvicidal activity against H rubidus and Oesophagostomum spp. At 50 mg per kg thiophanate administered alone was inactive against Ascaris suum and Metastrongylus apri, the former species also being refractory at 200 mg per kg. Field trials confirmed these efficacy results in naturally infected animals. Pellet formulations providing mean dosages of 63 mg thiophanate per kg for adult pigs and 75 mg thiophanate per kg with 83 mg piperazine base per kg for growing pigs were highly effective in reducing the faecal output of Oesophagostomum spp, H rubidus and T suis eggs. In growing pigs, A suum was controlled by the thiophanate/piperazine product. No palatability or tolerance problems were observed when thiophanate or thiophanate/piperazine mixtures were administered at recommended dosage or multiples thereof in experimental or field studies.

  18. 五种杀菌剂对水稻纹枯病田间药效评价%Evaluation on the Field Control Effect of Five Fungicides to Sheath Blight

    Institute of Scientific and Technical Information of China (English)

    陈广艳

    2011-01-01

    田间药效试验表明,500 g/L甲基硫茵灵悬浮剂、30%己唑醇悬浮剂、40%多茵灵悬浮剂、70%甲基硫茵灵可湿性粉剂、26%稻瘟酰胺·嘧茵酯悬浮剂5种杀茵剂均是防治水稻纹枯病的有效药剂,其中26%稻瘟酰胺·嘧茵酯悬浮剂防效最好,达78.15%.%Sheath blight, Thanatephorus cucurneris (Frank) Donk, is one of the three main rice disease. The field control effects of five fungicides have been examined in field tests. The results showed that Thiophanate-Methyl SC at the concentration of 500 g/L, Hexaconazole 30% SC, Carbendazim 40% SC, Thiophanate-Methyl 70% WP and Fenoxanil.Amistar 26% SC were effective fungicides to control sheath blight. Among the five fungicides, Fenoxanil. Amistar 26% SC was the best and the field control effect reached 78.15%.

  19. SENSIBILIDADE “IN VITRO” DE ISOLADOS DE Colletotrichum lindemuthianum A FUNGICIDAS “IN VITRO” SENSITIVITY OF ISOLATED Colletotrichum lindemuthianum TO FUNGICIDES

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    Aloísio Sartorato2 Sartorato

    2007-09-01

    Full Text Available

    Avaliou-se a sensibilidade "in vitro" de isolados do fungo Colletotrichum lindemuthianum aos fungicidas tiofanato metílico + clorotalonil, tiofanato metílico, fluazinam, clorotalonil, trifloxystrobin + propiconazole, piraclostrobin, difenoconazole e fentin hidróxido. Os diâmetros das colônias, sob os diferentes princípios ativos avaliados, diferiram significativamente da testemunha. Os isolados de C. lindemuthianum apresentaram alta sensibilidade aos princípios ativos difenoconazole, piraclostrobin, trifloxistrobin + propiconazole e fluazinam. A maioria dos isolados apresentou baixa sensibilidade ao tiofanato metílico, o que pode indicar a ocorrência de resistência do fungo C. lindemuthinaum a esse princípio ativo.

    PALAVRAS-CHAVE: Antracnose; resistência a fungicidas; controle químico.

    In vitro tests were carried out to evaluate the sensitivity of Colletotrichum lindemuthianum to the fungicides thiophanate methyl + chlorothalonil, thiophanate methyl, fluazinam, chlorothalonil, trifloxystrobin + propiconazole, pyraclostrobin, difenoconazole and fentin hidroxide. The fungus colony diameter of all isolates differed significantly from control in all active ingredient (a.i. used. C. lindemuthianum isolates presented higher sensitivity to the a.i. difenoconazole, pyraclostrobin, trifloxystrobin + propiconazole and fluazinam. The majority of isolates presented low sensitivity to methyl thiophanate, which may indicate the occurrence of C. lindemuthianum resistance to this active ingredient.

    KEY-WORDS: Anthracnose; resistance to fungicides; chemical control.

  20. 浓缩果汁中甲基硫菌灵、2-氨基苯并咪唑、多菌灵、噻菌灵及5-羟基噻菌灵残留量的液相色谱-串联质谱法测定%Simultaneous Determination of Thiophanate-methyl, 2-Aminobenzimidazole,Carbendazim, Triabendazole and 5-Hydroxy-triabendazole in Concentrated Fruit Juices by LC-MS/MS

    Institute of Scientific and Technical Information of China (English)

    刘晓松; 郑玲; 黄文雯; 卢炜; 宁恩创; 方晓明

    2013-01-01

    A liquid chromatography tandem mass spectrometric method was developed for the determination of benzimidazole fungicides and their metabolites such as thiophanate-methyl (TM ) , 2-amino-benzimidazole(2-AB), carbendazim ( MBC) , triabendazole (TBZ), 5-hydroxy-triabendazole(5-OH-TBZ) in 7 types of concentrated fruit juices including apple, mango, pineapple, pear, orange, ly-chee and passion fruit. Seven representative concentrated fruit juices were selected and extracted with acetonitrile. The extracts were purified with PSA column. The separation of 5 analytes was carried out on a ZORBAX Eclipse XDB - C18 column using methanol - 10 mmol/L ammonium acetate(containing 0. 1% formic acid) as mobile phase by gradient elution. The detection of analytes was performed by electrospray tandem mass spectrometry with ES + and multiple reaction monitoring ( MRM) modes. The results showed that, the method showed good linear relationships in the range of 0. 02 -0. 2 mg/L for the tested samples, with correlation coefficients no less than 0. 998 5. The quantitation limits were 2. 0 (μg/kg for 2-AB and 5-OH - TBZ, and 1.0 μ,g/kg for the rest of the analytes. The mean recoveries ranged from 70% to 110% with relative standard deviations of 0. 1% -10. 9% when the fortified levels for 2-AB and 5-OH-TBZ were 2, 4, 20 μg/kg and those for TBZ, MBC, TM were 1, 2, 10 μg/kg, respectively. The proposed method was sensitive and reliable, and was successfully applied in the determination of benzimidazole fungicides and their metabolites in real commercial concentrated juices.%建立了同时测定浓缩果汁中甲基硫菌灵(TM)、2-氨基苯并咪唑(2-AB)、多菌灵(MBC)、噻菌灵(TBZ)及5-羟基噻菌灵(5-OH-TBZ)的液相色谱-串联质谱法.选取7种代表性浓缩果汁进行研究,果汁样品先用乙腈提取,经PSA柱净化后,用ZORBAX Eclipse XDB-C18柱分离,以10 mmol/L乙酸铵-0.1%甲酸和甲醇为流动相进行梯度洗脱,四极杆串联质谱(MS/MS)采用电喷

  1. Side Effects of Fungicides Used in Cucurbitaceous Crop on Trichogrammaatopovirilia Oatman & Platner (Hymenoptera: Trichogramatidae Efectos Secundarios sobre Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogramatidae de Fungicidas usados en Cucurbitáceas

    Directory of Open Access Journals (Sweden)

    Dirceu Pratissoli

    2010-06-01

    Full Text Available Trichogramma spp. (Hymenoptera: Trichogrammatidae can control Diaphania hyalinata Linnaeus (Lepidoptera: Pyralidae. On the other hand, pesticides may reduce the efficiency of natural enemies. The objective was to evaluate the side-effects of fungicides used in the production of cucurbitaceous crops on Trichogramma atopovirilia Oatman & Platner parasitizing D. hyalinata eggs. The fungicides used in bioassays were: azoxystrobin (0.08 g active ingredient [ai] L-1, chlorothalonil (2.00 g ai L-1, mancozeb (1.60 g ai L-1, tebuconazole (0.25 g ai L-1 and thiophanate-methyl (0.49 g ai L-1. Cardboards with 30 D. hyalinata eggs previously immersedin fungicide solutions and distilled water (control were offered separately to 20 newly emerged T. atopovirilia females in glass tubes. Parasitism, parasitism reduction, emergence, sex ratio, and number of individuals per egg were evaluated. The fungicides chlorothalonil, thiophanate-methyl and tebuconazole reduced parasitism of T. atopovirilia by 43.37, 27.64 and 18.51%, respectively. However, parasitism with azoxystrobin (79.21% was higher than the control (67.37% (P ≤ 0.05. Chlorothalonil, thiophanate-methyl and tebuconazole reduced emergence by 73.77, 75.62 and 79.35% (P ≤ 0.05, respectively. Azoxystrobin and thiophanate-methyl reduced the sex ratio by 0.77 and 0.76 (P ≤ 0.05, respectively. Fungicides did not reduce the number of individuals per egg. The fungicides azoxystrobin and mancozeb were selective for T. atopovirilia for most studied parameters suggesting that these products must have the priority in crop disease management to allow efficient biological control of T. atopovirilia against D. hyalinata.Trichogramma spp. (Hymenoptera: Trichogrammatidae pueden controlar Diaphania hyalinata Linnaeus (Lepidoptera: Pyralidae. Sin embargo, los plaguicidas pueden reducir la eficiencia de los enemigos naturales. El objetivo de este trabajo fue evaluar la influencia de los fungicidas utilizados en la

  2. Fungicides Sensitivity of Podosphaera xanthii and Its Resistance Induction on Hull-less Pumpkin%裸仁美洲南瓜白粉病菌对几种杀菌剂敏感性及抗药性诱导

    Institute of Scientific and Technical Information of China (English)

    梁巧兰; 魏列新; 徐秉良

    2012-01-01

    [Aims] The objective of this paper is to study the sensitivity of Podosphaera xanthii on hull-less pumpkin and its resistance generation to some fungicides. [Methods] Control effects of several fungicides to P. xanthii were tested by indoor pot control effects test method and detached leaves-brushing with conidial suspension and medium with fungicides method. [Results] Six kinds of fungicides difenoconazole 10% WG, mancozeb+myclobutanil 62.5% WP, myclobutanil 5% EC, TF-120 2% AS, thiophanate-methyl 70% WP and hexaconazole 5% ME had good control effects on pumpkin powdery mildew and their sensitivity of pumpkin powdery mildew were affected in different application time. [Conclusions] The control effects of six kinds of fungicides all reached more than 80%. The EC50 values of difenoconazole, mancozeb+myclobutanil, myclobutanil, TF-120, thiophanate-methyl and hexaconazole to P. xanthii treated in different time after inoculation were determined, the results showed that the sensitive time of myclobutanil and thiophanate-methyl, hexaconazole and mancozeb+myclobutanil, TF-120 to P. xanthii on hull-less pumpkin were 48, 96 and 120 h respectively after inoculation; while the sensitive time of difenoconazole and thiophanate-methyl were 24 h before inoculation. Using the same fungicide repeatedly could induce the light resistance of P. xanthii to hexaconazole, the resistance factor was 6.79.%[目的]研究南瓜白粉病菌对几种杀菌剂敏感性及抗药性产生情况.[方法]防效试验采用室内盆栽方法和离体叶片含药培养基法.[结果]筛选出10%苯醚甲环唑WG、62.5%锰锌·腈菌唑WP、5%腈菌唑EC、2%农抗120 AS、70%甲基托布津WP和5%己唑醇ME 6种杀菌剂对南瓜白粉病菌有较好防效.接种后不同施药时间能够影响南瓜白粉病菌对杀菌剂的敏感性.[结论]筛选出的6种杀菌剂防效均在80%以上;几种药剂在不同时间对南瓜白粉病的EC50值测定结果表明:5

  3. Effect of the Different Fungicides on the Toxicity of Pleurotus ostreatus and Trichoderma spp.%不同杀菌剂对平菇及有害菌木霉的毒力测定

    Institute of Scientific and Technical Information of China (English)

    朱婷婷; 凌传秀

    2011-01-01

    [ Objective ] The inhibitory of four types of fungicides to Trichoderma spp. and Pleurotus ostreatus was tested. [ Method ] The effect of four types of fungicides with five concentrations on Trichoderma spp. and Pleurotus ostreatus, which were cultured with the method of plate medium containing different concentrations of fungicides, was analyzed. [ Results] The results showed that the order of the inhibitory to Trichoderma spp. growth was carbendazim > chlorothalonil > thiophanate methyl > Dithane M-45 and to Trichoderma spp. growth was thiophanate methyl > Dithane M-45 > chlorothalonil > carbendazim. At the concentration of 10.0 mg/L, the inhibition of carbendazim to Trichoderma spp. was 97.80% and to Pleurotus ostreatus was 52.08%. [Conclusion] The carbendazim could be used in Pleurotus ostreatus production.%[目的]测定4种常用杀菌剂对木霉及平菇的抑制作用.[方法]每种药剂设5个浓度梯度,制成培养基平板,测定各药剂对木霉及平菇的抑制作用.[结果]多菌灵对木霉的抑制作用最强,其余依次为百菌清、甲基硫菌灵和大生.甲基硫菌灵对平菇生长的抑制作用最大,其次是大生和百菌清,多菌灵对平菇生长的抑制作用较弱.在浓度为10 mg/L时,多菌灵对木霉生长的抑制率达到了97.80%.而对平菇的抑制率仅为52.08%,[结论]多菌灵可以作为拌料在平菇生产中推广应用.

  4. Effect of systemic fungicides on the efficacy of Pseudomonas aeruginosa (Schroeter migula in the control of root-infecting fungi of wheat

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    I. A. Siddiqui

    2013-12-01

    Full Text Available Effect of various fungicides on the efficacy of Pseudomonas aeruginosa, a plant growth-promoting rhizobacterium in the control of root-infecting fungi such as Macrophomina phaseolina, Fusarium oxysporum and F.solani on four different varieties of wheat was evaluated under field conditions. Bayleton (a.i. triadimephon, Bavistin (a.i. carbendazym and Topsin-M (a.i. thiophanate-methyl reduced bacterial survival on wheat seeds whereas Benlate (a.i. benomyl was not effective in this respect. P.aeruginosa used in combination with Benlate showed effective control of soilborne root-infecting fungi along with the enhancement of growth and grain yield of wheat.

  5. 几种杀菌剂对平菇生长的影响%Effect of the Different Fungicides on Pleurotus ostreatus

    Institute of Scientific and Technical Information of China (English)

    管怀骥

    2011-01-01

    The toxicity and effection of fruiting time and yield of four fungicides on Pleurotus ostreatus were studied, the results showed that the order of the inhibitory to Pleurotus ostreatus growth was Thiophanate · Methyl 〉 Dithane M - 45 〉 Chlorothaloni 〉 Carbendazim. the fruiting time of Thiophanate · Methyl at the content below 0.14% was 74 days, same as CK1 and CK,but short than that of the othe fungcides. The yield of Pleurotus ostreatus were decreased by using of fungicides, which was lower than that of CK. The yield by using of DithaneM -45 was high than that of CK1.%测定了4种杀菌剂对平菇菌丝生长的毒力作用及其对出菇时间、出菇量的影响,研究结果表明:甲基硫菌灵对平菇菌丝生长的抑制作用最强,其次为大生M-45和百菌清,多菌灵的抑制作用最弱,EC50为12.4947mg/L。甲基硫菌灵用量在0.14%以下,与多菌灵对照和无污染的空白对照的出菇时间均为74d,其它参试杀菌剂均使出菇推迟。参试药剂均使平菇产量降低,累计出菇量低于空白对照,其中大生M-45在推荐用量下的出菇量高于对照药剂多菌灵。

  6. Impacts of 6 fungicides on conidial germination of Metarhizium anisopliae%6种杀菌剂对金龟子绿僵菌孢子萌发的影响

    Institute of Scientific and Technical Information of China (English)

    叶小真; 陈全助; 宋漳; 陈耀群

    2012-01-01

    The inhibition of six fungicides on the germination of conidia of Metarhizium anisopliae were determined. The results showed that different fungicides had different inhibition on conidia of M. Anisopliae, and the inhibition decreased with declining concentration of fungicide. Among them, myclobutanil showed minimum inhibition on M. Anisopliae. Except the strain Mal03, the inhibition on other strains were less than 35%. The average inhibition rates of zineb on the stains Ma202, Ma201 and Ma203 were low. Other fungicides had obvisous inhibition on most strains of M. Anisopliae, especially chlorothalonil and thiophanate-methyl. The average inhibition rates of these two fungicides on the strains Mal03, Ma205, Ma207 and Ma208 were 100%. They also effectively inhibited the other strains. Therefore, we suggested that chlorothalonil, thiophanate-methyl and M. Anisopliae should not be applied in the field at the same time and place. Otherwise, the control effect of M. Anisopliae will be significantly influenced by these two fungicides.%测定了6种杀菌剂对金龟子绿僵菌分生孢子萌发的抑制作用.结果表明,不同杀菌剂对金龟子绿僵菌的抑制作用不同,且随着杀菌剂浓度的下降而减小.其中以腈菌唑的抑制效果最弱,除Ma103菌株外,对其他菌株抑制率均低于35%.代森锌对Ma202,Ma201和Ma203菌株的平均抑制率都较小.其他几种杀菌剂都明显抑制绿僵菌大部分菌株分生孢子的萌发,特别是百菌清和甲基托布津对Ma103,Ma205,Ma207和Ma208菌株的平均抑制率都为100%.2种药剂也强烈抑制其他菌株分生孢子的萌发.因此,应该尽量避免百菌清和甲基托布津与金龟子绿僵菌同时同地使用,否则会明显影响金龟子绿僵菌制剂的应用效果.

  7. Screening fungicide for pathogen inhibition and disease control of apple tree Valsa Canker%防治苹果树腐烂病杀菌剂的室内筛选

    Institute of Scientific and Technical Information of China (English)

    王磊; 郜佐鹏; 黄丽丽; 韦洁玲; 臧睿; 康振生

    2009-01-01

    The inhibitory effects of 10 fungicides on apple tree valsa canker were compared on dishes and twigs. The results showed that conidia germination and mycelial growth were inhibited by all fungicedes test-ed. The EC_(50) value of Difenoconazole was 6.1 × 10~(-3) μg · mL~(-1), the lowest among tested fungicide in inhi-biting conidia germination. Tebuconazole and Imazalil also showed obvious inhibition effect. Thiophanate-methyl was the least efficient with the EC_(50) value 2.6 × 10~1 μg · mL~(-1). Difenoconazole also showed the high-est activity for inhibiting mycelial growth with EC_(50) value of 2.3 × 10~(-2) μg · mL~(-1). Tebuconazole was better than other fungicide. Thiophanate-methyl and Propineb were the least efficient with quite high EC_(50) value. Furthermore, the size of the lesion after inoculation on excised twigs also revealed that Difenoconazole was most efficient because it showed the smallest lesion of 394 mm~2 compared with other tested fungicides. So Difenoconazole and Tebuconazole could be used to control apple tree valsa canker in field to substitute forbi-ded fungicides such as asomate.%@@ 2000年我国苹果栽培面积、产量为2.25×10~(10)m m~2和2.04×10~(10) kg,分别占世界苹果面积、产量的2/5和1/3.然而,由Valsa ceratosperma(无性阶段为Cytospora sp.)引起的苹果树腐烂病(ap-pie tree valsa canker)的大量普遍发生,严重影响和制约了苹果生产发展.Wang[1]2006年报道陕西省优质苹果生产区陕北地区苹果腐烂病的发生呈现出迅速上升的态势,而且普遍存在病疤复发的问题,果树一旦染病就很难治愈.

  8. Control Effect of Fungicides Against Twig Rot of Loquat Tree in Panxi Area of Sichuan%攀西地区枇杷枝干腐烂病农药防治试验

    Institute of Scientific and Technical Information of China (English)

    李元良; 陈雪梅; 王凤屏; 刘科华; 卢照富

    2015-01-01

    Experiment of fungicides against twig rot of loquat was conducted in Panxi area of Sichuan Province during 2013 to 2014. Of all tested fungicides, Guoshukang, thiophanate-methyl + 1-naphthylacetic acid and dioctyl divinyltriamino glycine have significant effect on this disease, with recovery averaged in 90% or more. The other two fungicides, named thiodia-zole copper and procymidone, also have a certain control effect (85% above). They can be recommended to production use.%2013-2014年在四川攀西地区进行枇杷枝干腐烂病的农药防治试验,结果表明,果树康、甲硫·萘乙酸、菌清对枇杷枝干腐烂病防治有明显效果,平均病斑治愈率在90%以上,其次为噻菌酮、腐霉利,平均病斑治愈率在85%以上,均可向生产推荐使用。

  9. Unlikely remedy: fungicide clears infection from pathogenic fungus in larval southern leopard frogs (Lithobates sphenocephalus.

    Directory of Open Access Journals (Sweden)

    Shane M Hanlon

    Full Text Available Amphibians are often exposed to a wide variety of perturbations. Two of these, pesticides and pathogens, are linked to declines in both amphibian health and population viability. Many studies have examined the separate effects of such perturbations; however, few have examined the effects of simultaneous exposure of both to amphibians. In this study, we exposed larval southern leopard frog tadpoles (Lithobates sphenocephalus to the chytrid fungus Batrachochytrium dendrobatidis and the fungicide thiophanate-methyl (TM at 0.6 mg/L under laboratory conditions. The experiment was continued until all larvae completed metamorphosis or died. Overall, TM facilitated increases in tadpole mass and length. Additionally, individuals exposed to both TM and Bd were heavier and larger, compared to all other treatments. TM also cleared Bd in infected larvae. We conclude that TM affects larval anurans to facilitate growth and development while clearing Bd infection. Our findings highlight the need for more research into multiple perturbations, specifically pesticides and disease, to further promote amphibian heath.

  10. 九种杀菌剂对Fusarium verticillioides和F.graminearum毒力及玉米穗腐病的防治效果%Toxicity and Field Control Effect of Nine Fungicides Against Fusarium Ear Rot

    Institute of Scientific and Technical Information of China (English)

    隋韵涵; 肖淑芹; 董雪; 薛春生; 陈捷

    2014-01-01

    采用含毒介质法分别测定玉米穗腐病菌禾谷镰孢菌和拟轮枝镰孢菌对9种药剂的敏感性,在田间进行防治玉米穗腐病的药效试验,综合评价化学和生物药剂以及不同施药处理对玉米穗腐病的防治效果。室内毒力测定结果表明,9种药剂在一定浓度下对玉米穗腐病均有毒力作用,10%苯醚甲环唑、70%甲基托布津对禾谷镰孢菌毒力较强;70%甲基托布津对轮枝镰刀菌毒力较强,10%苯醚甲环唑次之。田间药效试验结果表明,50%异菌脲可湿性粉剂防效为92.3%,5%井冈霉素为80.64%;且先接菌后喷药的防治效果优于先喷药后接菌处理。%Toxicity of nine fungicides to Fusarium verticillioide and Fusarium graminearum were tested by toxic media method in lab and control experiment was also conducted in the field. Control efficacy and treatment application of chemical and biological fungicide to corn ear rot were comprehensive evaluated. The result of toxicity indicated that Difenoconazole and Thiophanate-methyl showed strong toxicity against Fusarium graminearum, Thiophanate-methyl, Difenoconazole showed strong toxicity against Fusarium verticillioides. The results of field control indicated that the control efficacies of Iprodione and Jingangmeisu were 92.3%and 80.64%, and control efficacy of spraying fungicides after inoculation, was better than that of inoculation after spraying fungicides.

  11. Efeito de fungicidas no controle in vitro de Colletotrichum gloeosporioides, agente etiológico da antracnose do mamoeiro (Carica papaya l. Effects of fungicides on the in vitro control of Colletotrichum gloeosporioides, the anthracnosis etiologic agent of the Papaya tree (Carica papaya L.

    Directory of Open Access Journals (Sweden)

    Giltembergue Macedo Tavares

    2005-02-01

    , thiabendazol and thiophanate-methyl in the concentrations of 0, 1, 10, 100, 500 and 1.000 ppm to evaluate the inhibition of the mycelial growth and in the concentrations of 0, 1, 10, 50 and 100 ppm to test inhibition of the conidial germination. The fungicides azoxystrobin, chlorotalonil, imazalil, prochloraz, propiconazol and tebuconazol presented high efficiency in the inhibition of the mycelial growth. The fungicides of the benzimidazol group (thiabendazol and thiophanate-methyl showed low efficiency in the control of C. gloeosporioides. Sodium hypochloride showed low efficiency in the control of the mycelial growth of the fungus. For inhibition of the conidial germination, the fungicides oxychloride, chlorothalonil and sodium hypochloride showed high efficiency, even at low concentrations. C. gloeosporioides showed to be tolerant to the fungicides thiabendazole and thiophanate-methyl, as conidial germination and mycelial growth were not affected in the presence of these products.

  12. Mold Resistance and Leachability of 5-Methyl Carbendazim Fungicide%5-甲基多菌灵的防霉性和抗流失性

    Institute of Scientific and Technical Information of China (English)

    崔爱玲; 黄涛; 翟炜; 程康华

    2013-01-01

    In order to develop carbendazim fungicide for wood-based products,2-carbamatebenzimidazole carbendazim (MBC) was modified to 2-carbamate-5-methyl-benzimidazole (MMBC).Mold resistance and leachability of MMBC were tested.The results showed that mold resistance of MMBC was better than pentachlorophenol sodium (Na-pcp) and leachability was improved compared with MBC.%为开发防霉效果优良的木材用防霉剂,对2-氨基甲酸甲酯苯并咪唑(多菌灵,MBC)进行改性,得到2-氨基甲酸甲酯-5-甲基苯并咪唑(MMBC).经检测MMBC处理材的防霉性和抗流失性,结果表明:MMBC的防霉性优于传统防霉剂五氯酚钠,且流失率较改性前有所降低.

  13. Laboratory Screening and Field Control Effect of Five Kinds of Fungicides on Tomato Basal Stem Rot%5种杀菌剂防治番茄茎腐病的室内筛选和田间使用效果

    Institute of Scientific and Technical Information of China (English)

    任凤山; 高亮; 张博

    2016-01-01

    笔者旨在通过筛选防治番茄茎腐病的有效药剂,为田间防治提供指导。室内测定了5种杀菌剂对终极腐霉菌丝生长的抑制作用,恶霉灵、唑醚·代森联、硫酸铜钙、甲基硫菌灵和恶酮·霜脲氰为有效杀菌剂。研究结果表明:恶霉灵的EC50为0.364 mg/L,抑菌效果最好;唑醚·代森联效果次之,EC50为9.247 mg/L,其他药剂防治效果相对较差。在田间药剂筛选试验中,70%恶霉灵可湿性粉剂与70%甲基硫菌灵可湿性粉剂组合防治效果为95.57%,均优于其它供试药剂组合,可应用于番茄茎腐病的田间防治。%The paper aims to screen out effective fungicides to control tomato basal stem rot and provide guidance for field control. Inhibiting effect of 5 fungicides on the growth of Pythium ultimum was investigated indoor. The test verified that the 5 fungicides, hymexazol, ovraclostrobin · metiram, copper calcium sulphate, thiophanate-methyl and famoxadone · cymoxanil, had control effect on the growth of Pythium ultimum. The results showed that hymexazol had the best antibacterial effect with the EC50 value of 0.364 mg/L, then was ovraclostrobin·metiram with the EC50 value of 9.247 mg/L, other fungicides had poor control efficiency. In field fungicide screening test, the combined control efficiency of 70%hymexazol WP and 70%thiophanate-methyl WP was 95.57%, which was better than other combinations and could be used in field control.

  14. 不同杀菌剂对油梨炭疽病菌的抑菌效果%Antibacterial Effect of Different Fungicides on Avocado anthracnos

    Institute of Scientific and Technical Information of China (English)

    韦文添

    2014-01-01

    In order to screen fungicides effectively suppressing A.anthracnose,toxicity of eight fungicides on A.anthracnose were measured.Results:The toxicity of 10% difenoconazole WDG was the strongest,with the EC50 of 2.829 1 mg/L,followed by 80% ethylicin EC and 25% bromothalonil WP with the EC50 of 13.522 8 mg/L and 16.698 3 mg/L,45% prochloraz EW and 70% Thiophanate-Methyl WP with the EC50 of 36.5306mg/L and 192.838 6 mg/L. The sensitivity of pepper anthracnose 75%chlorothalonil WP ,80% mancozeb WP and 80% captan WDG were lower than others.10% difenoconazole WDG,80% ethylicin EC,25% bromothalonil WP,45% prochloraz EW and 70% Thiophanate-Methyl WP can effectively inhibit the growth of A.anthracnose.%为了筛选有效抑制油梨炭疽病菌的杀菌剂,测定了8种杀菌剂对油梨炭疽病菌的室内抑菌率和毒力。结果表明:抑菌率较高的是45%咪鲜胺EW和70%甲基硫菌灵 WP,达72%以上;其次是25%溴菌清 WP、10%苯醚甲环唑 WDG 和80%乙蒜素 EC,抑菌率均大于61%;80%代森锰锌 WP、75%百菌清WP和80%克菌丹 WDG 抑菌率较低。对油梨炭疽病菌毒力最强的是10%苯醚甲环唑 WDG,EC50为2.8291 mg/L;其次是80%乙蒜素 EC和25%溴菌清 WP,EC50分别为13.5228 mg/L和16.6983 mg/L。结论:10%苯醚甲环唑 WDG、80%乙蒜素EC、25%溴菌清 WP、45%咪鲜胺 EW和70%甲基硫菌灵 WP对油梨炭疽病菌的生长有一定的抑制作用。

  15. Comparative efficacies of closantel, ivermectin, oxfendazole, thiophanate and levamisole against thiabendazole resistant Haemonchus contortus in sheep.

    Science.gov (United States)

    Waruiru, R M; Weda, E H; Otieno, R O; Ngotho, J W; Bøgh, H O

    1996-08-01

    Forty-nine sheep artificially exposed to a thiabendazole (TBZ) resistant isolate of Haemonchus contortus were assigned to 7 groups of 7 animals each and used to conduct a controlled anthelmintic trial. One group of sheep served as untreated infected controls and 6 groups were treated as follows: closantel, 5.0 mg kg-1; ivermectin, 0.2 mg kg-1; oxfendazole, 5.0 mg kg-1; thiophanate, 50 mg kg-1, levamisole, 7.5 mgkg-1 and thiabendazole, 66 mg kg-1. Eggs per gram of faeces were determined on days 21, 24 and day 34 (10 days post-treatment) after infection and all animals were necropsied for residual worm counts. The calculated efficacies of the treatments against H. contortus as indicated by worm reduction were closantel (100%), ivermectin (99.3%), oxfendazole (35.2%), thiophanate (56.7%), levamisole (98.6%) and thiabendazole (24.3%). The data therefore indicate that the TBZ-resistant isolate of H. contortus used was highly resistant to the 2 benzimidazole (BZ) anthelmintics, oxfendazole and thiophanate. This is the first report in Kenya of a field strain of H. contortus resistant to thiophanate.

  16. 复合药肥对番茄灰霉病防治研究%Study on Controlling Grey Mould Diseases and Increasing Photosynthetic Efficiency with Multiple Fungicides Fertilizers

    Institute of Scientific and Technical Information of China (English)

    王克勤; 刘春来; 朱玉芹; 李新民; 于恒纯; 李大伟

    2001-01-01

    The resistant strains of Botrytis cinerea to carbendazim and thiophanate-methyl were discovered in Harbin outskirts by field investigation and controlling fungus test in lab. Multiple fungicides fertilizers (derived from fungicide and fertilizer) made by ourselves have good controlling effect to Botrytis cinerea. The effect of 1%~2%compound was a hundred percent to controlling Botrytis cinerea after 48 hours and 72 hours in lab , eighty percent to controlling grey mould diseases in field. They also have a good effect to controlling the leaf mould disease. We sprayed the compound at green fruit stage and fruit setting stage on tomato. Photosynthetic efficiency of the leaf increased by 30%~40%.%通过田间调查和室内抑菌试验发现哈尔滨市郊区已出现了抗多菌灵兼抗甲托的灰霉菌抗性菌株。复合药肥对灰霉菌有很好的抑制作用,对番茄灰霉病的田间防治效果达80%以上,同时能兼防番茄叶霉病。在番茄作果期和青果期喷施复合药肥,能够提高番茄叶片光合速率30%~40%。

  17. Methyl and p-Bromobenzyl Esters of Hydrogenated Kaurenoic Acid for Controlling Anthracnose in Common Bean Plants.

    Science.gov (United States)

    Mota, Suellen F; Oliveira, Denilson F; Heleno, Vladimir C G; Soares, Ana Carolina F; Midiwo, Jacob O; Souza, Elaine A

    2017-03-01

    Kaurenoic acid derivatives were prepared and submitted to in vitro assays with the fungus Colletotrichum lindemuthianum, which causes anthracnose disease in the common bean. The most active substances were found to be methyl and p-bromobenzylesters, 7 and 9, respectively, of the hydrogenated kaurenoic acid, which presented a minimum inhibitory concentration (MIC) of 0.097 and 0.131 mM, respectively, while the commercial fungicide methyl thiophanate (MT) presented a MIC of 0.143 mM. Substances 7 (1.401 mM) and 9 (1.886 mM) reduced the severity of anthracnose in common bean to values statistically comparable to MT (2.044 mM). According to an in silico study, both compounds 7 and 9 are inhibitors of the ketosteroid isomerase (KSI) enzyme produced by other organisms, the amino acid sequence of which could be detected in fungal genomes. These substances appeared to act against C. lindemuthianum by inhibiting its KSI. Therefore, substances 7 and 9 are promising for the development of new fungicides.

  18. Independent Emergence of Resistance to Seven Chemical Classes of Fungicides in Botrytis cinerea.

    Science.gov (United States)

    Fernández-Ortuño, Dolores; Grabke, Anja; Li, Xingpeng; Schnabel, Guido

    2015-04-01

    Gray mold, caused by the fungal pathogen Botrytis cinerea, is one of the most destructive diseases of small fruit crops and control is largely dependent on the application of fungicides. As part of a region-wide resistance-monitoring program that investigated 1,890 B. cinerea isolates from 189 fields in 10 states of the United States, we identified seven isolates (0.4%) from five locations in four different states with unprecedented resistance to all seven Fungicide Resistance Action Committee (FRAC) codes with single-site modes of action including FRAC 1, 2, 7, 9, 11, 12, and 17 registered in the United States for gray mold control. Resistance to thiophanate-methyl, iprodione, boscalid, pyraclostrobin, and fenhexamid was based on target gene mutations that conferred E198A and F200Y in β-tubulin, I365N/S in Bos1, H272R/Y in SdhB, G143A in Cytb, and T63I and F412S in Erg27. Isolates were grouped into MDR1 and MDR1h phenotypes based on sensitivity to fludioxonil and variations in transcription factor mrr1. MDR1h isolates had a previously described 3-bp deletion at position 497 in mrr1. Expression of ABC transporter atrB was increased in MDR1 isolates but highest in MDR1h isolates. None of the isolates with seven single resistances (SR) had identical nucleotide variations in target genes, indicating that they emerged independently. Multifungicide resistance phenotypes did not exhibit significant fitness penalties for the parameters used in this study, but MDR1h isolates produced more sclerotia at low temperatures and exhibited increased sensitivity to salt stress. In this study we show that current resistance management strategies have not been able to prevent the geographically independent development of resistance to all seven site-specific fungicides currently registered for gray mold control in the United States and document the presence of MDR1h in North America.

  19. The evolution of fungicide resistance.

    Science.gov (United States)

    Lucas, John A; Hawkins, Nichola J; Fraaije, Bart A

    2015-01-01

    Fungicides are widely used in developed agricultural systems to control disease and safeguard crop yield and quality. Over time, however, resistance to many of the most effective fungicides has emerged and spread in pathogen populations, compromising disease control. This review describes the development of resistance using case histories based on four important diseases of temperate cereal crops: eyespot (Oculimacula yallundae and Oculimacula acuformis), Septoria tritici blotch (Zymoseptoria tritici), powdery mildew (Blumeria graminis), and Fusarium ear blight (a complex of Fusarium and Microdochium spp). The sequential emergence of variant genotypes of these pathogens with reduced sensitivity to the most active single-site fungicides, methyl benzimidazole carbamates, demethylation inhibitors, quinone outside inhibitors, and succinate dehydrogenase inhibitors illustrates an ongoing evolutionary process in response to the introduction and use of different chemical classes. Analysis of the molecular mechanisms and genetic basis of resistance has provided more rapid and precise methods for detecting and monitoring the incidence of resistance in field populations, but when or where resistance will occur remains difficult to predict. The extent to which the predictability of resistance evolution can be improved by laboratory mutagenesis studies and fitness measurements, comparison between pathogens, and reconstruction of evolutionary pathways is discussed. Risk models based on fungal life cycles, fungicide properties, and exposure to the fungicide are now being refined to take account of additional traits associated with the rate of pathogen evolution. Experimental data on the selection of specific mutations or resistant genotypes in pathogen populations in response to fungicide treatments can be used in models evaluating the most effective strategies for reducing or preventing resistance. Resistance management based on robust scientific evidence is vital to prolong

  20. Alternative solvent-based methyl benzoate vortex-assisted dispersive liquid-liquid microextraction for the high-performance liquid chromatographic determination of benzimidazole fungicides in environmental water samples.

    Science.gov (United States)

    Santaladchaiyakit, Yanawath; Srijaranai, Supalax

    2014-11-01

    Vortex-assisted dispersive liquid-liquid microextraction using methyl benzoate as an alternative extraction solvent for extracting and preconcentrating three benzimidazole fungicides (i.e., carbendazim, thiabendazole, and fluberidazole) in environmental water samples before high-performance liquid chromatographic analysis has been developed. The selected microextraction conditions were 250 μL of methyl benzoate containing 300 μL of ethanol, 1.0% w/v sodium acetate, and vortex agitation speed of 2100 rpm for 30 s. Under optimum conditions, preconcentration factors were 14.5-39.0 for the target fungicides. Limits of detection were obtained in the range of 0.01-0.05 μg/L. The proposed method was then applied to surface water samples and the recovery evaluations at three spiked concentration levels of 5, 30, and 50 μg/L were obtained in the range of 77.4-110.9% with the relative standard deviation water samples.

  1. Ação de acibenzolar-s-methyl isolado e em mistura com fungicidas no controle da requeima da batata Action of acibenzolar-S-methyl, isolated and in a mixture with fungicides on potato late blight control

    Directory of Open Access Journals (Sweden)

    Jesus G. Töfoli

    2005-07-01

    Full Text Available Visando avaliar o desempenho de acibenzolar-S-methyl (BTH isolado e em mistura com os fungicidas mancozeb, chlorothalonil e metaxyl-M+chlorothalonil no controle da requeima da batata, foram realizados dois experimentos em cultivos comerciais nos municípios paulistas de Pilar do Sul (cv. Baraka e Bragança Paulista (cv. Asterix, de maio a agosto e agosto a outubro de 2001, respectivamente. O delineamento experimental foi o de blocos ao acaso com 4 repetições, com cada parcela medindo 25 m². Durante os experimentos foram realizadas um total de 10 pulverizações, a intervalos de 5 a 10 dias com pulverizador costal munido de barra de aplicação contendo 5 bicos TXKV26, pressão constante (4 bar e volume médio de 800 L/ha. Avaliou-se a severidade nas folhas (0 a 100%, nas hastes ( escala de notas de 1 a 5 e a produtividade comercial de tubérculos. O BTH apresentou efeitos significativos de controle quando utilizado isolado e em mistura com fungicidas de contato e sistêmico. Os maiores aumentos relativos de produtividade foram verificados para as misturas de BTH com mancozeb e chlorothalonil.To evaluate the performance of acibenzolar-S-methyl (BTH, alone and mixed with mancozeb, chlorothalonil and metaxyl-M+chlorothalonil, for the control of potato late blight, two experiments were carried out in commercial crops in the counties of Pilar do Sul (cv. Baraka and Bragança Paulista (cv. Asterix, state of São Paulo, Brazil, from May to August and August to October 2001, respectively. The experimental design was of randomized blocks with four replications, with each plot measuring 25 m². A total of 10 sprayings was done at 5- to 10-day intervals with a backpack sprayer using a 5-nozzle (TXKV26 spray wand, constant pressure of 4 bars (58 psi and average volume of 800 L/ha. Evaluations were done in regard to the severity on the leaves (0 to 100%, on the stems (score from 1 to 5 and the commercial yield of tubers. BTH presented expressive effects

  2. Tratamento fungicida de sementes de soja inoculadas com Colletotrichum truncatum Fungicide treatment of soybean seeds inoculated with Colletotrichum truncatum

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Pereira

    2009-12-01

    Full Text Available A qualidade sanitária e o potencial fisiológico de sementes de soja são fatores determinantes para o estabelecimento de estandes adequados. Assim, objetivou-se avaliar o desempenho das sementes de soja e o crescimento das plantas após inoculação das sementes com Colletotrichum truncatum e tratamento fungicida via peliculização. As sementes foram inoculadas com C. truncatum utilizando técnica de restrição hídrica e, posteriormente, tratadas com fungicidas e polímero. Os tratamentos utilizados foram carbendazin, fludioxonil+mefenoxan, thiabendazol+thiram, tiofanato metílico, caboxin+thiram e sementes não tratadas. As sementes foram tratadas com e sem polímero. Foram realizadas avaliações de germinação das sementes, teste de frio, emergência de plântulas e sanidade das sementes por meio do Blotter test. As plantas, cultivadas em vasos, foram avaliadas pelo comprimento da parte aérea, da matéria seca de raízes e da parte aérea. O tratamento das sementes de soja com fludioxonil+mefenoxan e thiabendazole+thiram é eficiente no controle de Colletotrichum truncatum e melhora o desempenho fisiológico das sementes. O desempenho das sementes de soja e o crescimento das plantas são reduzidos quando as sementes são tratadas com tiofanato metílico. A peliculização não afeta o potencial fisiológico e a qualidade sanitária das sementes de soja.The sanitary and physiological qualities of soybean seeds are determining factors for the establishment of appropriate stands. This research aimed to evaluate the soybean seed performance and plants growth after seed inoculation with Colletotrichum truncatum and fungicide treatment by film-coating. The seeds were inoculated whit C. truncatum by water restriction technique and then treated with fungicides and polymer. The used treatments were carbendazin, fludioxonil+mefenoxan, thiabendazole+thiram, thiophanate methyl, caboxin+thiram and untreated seeds. The seeds were treated with and

  3. Study on Control Efficiency of Several Fungicides on Spot Blight in Scrophularia ningpoensis Hemsl.%几种药剂防治玄参斑枯病药效试验

    Institute of Scientific and Technical Information of China (English)

    陈大霞; 李隆云; 宋春泉; 曾凡明; 吴叶宽

    2011-01-01

    [Objective] To study the control efficiency of several fungicides on spot blight in Scrophularia ningpoensis Hemsl.. [Method] Scro-phularia ningpoensis Hemsl. Son shoots were soaked in 4 fungicides respectively before planting, and then their control efficiencies on field diseases were investigated after onset; field control experiment against disease was carried out to screen the effectual chemicals for the control of this disease. [Result] By soaking son shoots, 4 fungicides could effectively control spot blight and significantly improve survival rate of Scrophularia ningpoensis Hemsl. Seedling. The control efficiency of 80% rarbendazim at 1:800 concentration against spot blight was the highest (67.1% ) , followed by 70% thiophanate -methyl at 1 :1 000 concentration (65. 6% ). Both fungicides could achieve better control efficiency in the early stage of spot blight. [Conclusion] Treatment of non shoots with fungicides combined with field spraying control could effectively control spot blight Scrophularia ningpoensis Hemsl. And minimize losses.%[目的]研究几种药剂防治玄参(Scrophularia ningpoensis Hemsl.)斑枯病的药效.[方法]玄参在栽种前以4种杀菌剂进行子芽浸种处理,田间发病后调查不同处理的防治效果;在玄参斑枯病发病初期,以5种杀菌剂进行田间药剂防效试验.[结果]用4种杀菌剂浸种后均能有效的防治玄参斑枯病,且能显著提高保苗率;5种杀菌剂的田间药剂防效以80%多菌灵800倍液(67.1%)和70%甲托1000倍液(65.6%)的防效最好,在斑枯病发病初期,能达到较理想的控制效果.[结论]采用药剂处理玄参子芽,结合田间施药防治可有效的防治玄参斑枯病,使损失降到最低.

  4. Fungicide Screening of Controlling Beet Damping-off in indoor Germination Stage%防治甜菜苗期立枯病杀菌剂的室内筛选Ⅰ

    Institute of Scientific and Technical Information of China (English)

    高有军; 王维成; 王宏科; 王荣华; 刘万林; 冯锴

    2014-01-01

    应用10种杀菌剂,在种衣剂中有效成分含量0.1%~1.0%内设置5个浓度梯度,通过发芽试验筛选出较佳用量及较优杀菌剂。结果表明,最佳浓度为:福美双、多菌灵、萎锈灵、苯醚甲环唑、甲基托布津0.3%,五氯硝基苯、百菌清、咯菌腈、立枯磷0.5%,恶霉灵0.6%;最佳杀菌剂为苯醚甲环唑,其次为萎锈灵。可为研制甜菜种衣剂提供理论依据。%Fungicides controlling beet damping-off were selected by 5 concentrations in indoor germination stage. The results showed that optimum concentration was of 0.3% thiram, carbendazim, carboxin, difenoconazole and thiophanate methyl; of 0.5% quintozene, chlorothalonil, fludioxonil and tolclofos; 0.6% hymexazol. The best control effect on beet damping-off was difenoconazole and carboxin as the second.

  5. 40 CFR 180.371 - Thiophanate-methyl; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ....15 Grape 5.0 Horse, fat 0.15 Horse, meat 0.15 Horse, meat byproducts 0.15 Milk 0.15 Onion, bulb 0.5....1 Sheep, fat 0.15 Sheep, meat 0.15 Sheep, meat byproducts 0.15 Soybean, seed 0.2 Soybean, hulls...

  6. Indoor Toxicity Measurement of Five Fungicides on Gummy Stem Blight from Netted Melon%5种杀菌剂对网纹甜瓜蔓枯病菌的室内毒力测定

    Institute of Scientific and Technical Information of China (English)

    韦文添

    2013-01-01

    为筛选出有效防治网纹甜瓜蔓枯病的药剂,采用菌丝生长速率法,测定了5种杀菌剂对网纹甜瓜蔓枯病菌的抑菌作用.结果表明:5种杀菌剂中,25%溴菌清WP对网纹甜瓜蔓枯病病原菌的毒力最强,EC50值为64.051 1 mg/L;80%克菌丹WDG和80%代森锰锌WP次之,EQ50值分别为161.006 9 mg/L和259.921 6 mg/L;70%甲基硫菌灵WP和75%百菌清WP的毒力最差.25%溴菌清WP、80%克菌丹WDG和80%代森锰锌WP均可有效抑制网纹甜瓜蔓枯病菌的生长,可进一步用于田间试验.%In order to select fungicides that can effectively control gummy stem blight, bacteriostasis of five fungicides on muskmelon gummy stem blight was measured using mycelium growth rate method. The results showed that the toxicity of bromothalonil 25% WP was the strongest, with the EC50 of 64. 051 1 mg/L. Followed by captan 80% WDG and mancozeb 80% WP with the EC50 of 161. 006 9 and 259. 921 6 mg/L, respectively. While thiophanate-Methyl 70% WP and chlorothalonil 75% WP were lower than others. Bromothalonil 25% WP, captan 80% WDG and mancozeb 80% WP could effectively inhibit the growth of muskmelon gummy stem blight and could be used in field trials.

  7. 6种杀菌剂对兰花枯萎病菌抑制作用比较%Comparison of Inhibition of Six Fungicides against Fusarium oxysporum f.sp.Cattleyae

    Institute of Scientific and Technical Information of China (English)

    焦鹏; 贾变桃; 孙颖; 杨素梅

    2012-01-01

    growth. The benzimidazole fungicide thiophanate-methyl had some activity on spore germination, but with very low activity on mycelial growth. These results provide a beneficial reference for control of orchid wilt pathogen.

  8. 杀菌剂对甘薯致病菌Hypocrea sp.SP-4和Rhizopus stolonifer SP-1生长影响研究%Studies on Influence of Fungicide on Growth of Hypocrea sp.SP-4 and Rhizopus stolonifer SP-1 of Pathogenic Bacteria of Sweet Potato

    Institute of Scientific and Technical Information of China (English)

    段鹏; 张义正; 谭雪梅

    2011-01-01

    为了研究杀菌剂对甘薯致病菌 Hypocrea sp.SP-4和Rhizopus stolonifer SP-1生长的抑制效果,本文从腐烂的甘薯块根中分离到的匍枝根霉SP-1(Rhizopus stolonifer SP-1)和Hypocrea sp.SP-4的孢子接种在含有不同杀菌剂浓度的PDA培养基上,在13℃和28℃条件下培养.同时也将2种孢子接种在甘薯块根上,进行培养观察.结果表明:2株真菌低温条件下,在不含杀茵剂的培养皿上的生长速度明显比28℃条件下要缓慢些;甲基托布津和多茵灵对Hypocrea sp.SP-4和R.stolonifer SP-1生长抑制的稀释度分别为1000倍和500倍.在28℃条件下,2种杀菌剂对Hypocrea sp.SP-4都有良好的抑制效果,但对R.stolonifer SP-1抑制率,甲基托布津只有21%,多菌灵则有58%.在用杀菌剂抑制甘薯块根侵染的过程中还发现,甘薯块根在没有创伤的情况下,2株真菌在低温条件下不会引起腐烂,说明它们是通过伤口侵染甘薯块根的.综合几个指标可以得出:适度低温和避免甘薯块根出现伤口能够减少甘薯块根被真菌侵染.%In order to study on influence of fungicide on growth of Rhizopus stolonifer SP-1 and Hypocrea sp SP-4 of pathogenic bacteria of sweet potato, spores of Rhizopus stolonifer SP-1 and Hypocrea sp SP-4 isolated from spoilage root tuber of sweet potato were inoculated on PDA medium plate and root tuber of sweet potato including different concentrations of fungicide, and cultivated at 13℃ and 28℃. The results showed that they grew more slowly at 13℃ than 28℃. Dilution concentration of thiophanate-methyl and carbendazol to inhibit the growth of Hypocrea sp SP-4 and R. stolonifer SP-1 is 1000 and 500-fold, respectively. Both fungicides could efficiently inhibit the growth of Hypocrea sp SP-4. However, the inhibition rate of thiophanate-methyl and carbendazol to R. stolonifer SP-1 is 21% and 58%, respectively. The results also showed in the course of fungicide inhibiting the infection of root tuber of

  9. New Look at odorization levels for propane gas. [Ethyl mercaptan; thiophane; equilibrium K values

    Energy Technology Data Exchange (ETDEWEB)

    Whisman, M.L.; Goetzinger, J.W.; Cotton, F.O.; Brinkman, D.W.; Thompson, C.J.

    1977-09-01

    Nearly 4,000 persons participated in a study to evaluate three odorant systems in four test modes and at 24 different test sites. Participants included trained panels, untrained ERDA employees, and several thousand untrained volunteer evaluators. The classical testing technique and three modified test modes were used to represent a spectrum of conditions that would define the effect of environmental familiarity and mental distractions upon olfactory responses to LP-gas. Significant efforts were directed toward determination of odorant levels that not only can be detected but also will be detected. The study showed that in addition to defects of the nasal anatomy, psychological factors also affect olfactory responses, and that unfamiliarity with a given environment as well as anxieties or mental distractions can produce reduced awareness to odorants intended to warn individuals of the presence of LP-gas. A second part of the study involved a laboratory determination of equilibrium K-values for both ethyl mercaptan and thiophane at three temperatures. Novel sample handling and gas chromatographic techniques provided reproducible results which were in close agreement with theoretical predictions. (28 tables, 29 tables)

  10. Probabilistic Exposure Assessment for Applicators during Treatment of the Fungicide Kresoxim-methyl on an Apple Orchard by a Speed Sprayer.

    Science.gov (United States)

    Kim, Eunhye; Moon, Joon-Kwan; Choi, Hoon; Kim, Jeong-Han

    2015-12-09

    Probabilistic exposure and risk assessment of kresoxim-methyl were conducted for agricultural applicators during preparation of spray suspension and application with a speed sprayer on an apple orchard. The preparation and application of 1000 L of spray suspension were repeated 30 times. Several exposure matrices, including patches, cotton gloves, socks, masks, and XAD-2 resin, were used to measure the potential exposure for workers. The analytical methods were fully validated to guarantee the precision and accuracy of analysis. The exposure amount on hands for mixer/loader was 0.7 mg [95% confidence interval (CI) from 0.02 to 2.4], taking 0.0005% (95% CI from 1.2 × 10(-5) to 0.001) of total prepared active ingredient. During application of kresoxim-methyl, the amount of dermal exposure was 17.5 mg (95% CI from 9.3 to 28.9), corresponding to 0.010% (95% CI from 0.006 to 0.017) of total applied active ingredient. The major exposure parts of the body were thighs and shins, with correlation coefficients of 0.53 and 0.43, respectively. The inhalation exposure during application were estimated as 6.8 ng (95% CI from 0.4 to 17.0), being 0.04% (95% CI from 0.004 to 0.06) of the dermal exposure. The calculated absorbable quantities of exposures for mixer/loader and applicator were 2.1 × 10(-4) mg/day (95% CI from 5.0 × 10(-6) to 7.2 × 10(-4)) and 2.3 mg/day (95% CI from 1.2 to 3.8), respectively. For risk assessment, the margin of safety of all working activities was much higher than 1, indicating that the possibility of risk to kresoxim-methyl was unlikely.

  11. 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...

  12. Virulence Test of 3 Styrene Acrylic Imidazole Fungicides to Rhizoctonia solani%苯并咪唑类杀菌剂对水稻纹枯病菌的室内毒力测定

    Institute of Scientific and Technical Information of China (English)

    袁梦思; 李建文; 孙文秀

    2016-01-01

    The susceptibilities of Rhizoctonia solani Kohn with different resistance to three styrene acrylic imidazole fungicides were tested by using mycelium growth rate method. The results showed that the inhibition of carbendazim against R. solani was the highest. The EC50 against sensitive strains were 0.2931~0.4035μg/mL, and against resistant strains were 0.4147~0.6457 μg/mL. The virulence of thiophanate-methyl was the lowest. The EC50 against sensitive and resistant strains were 12.0397~26.5971μg/mL and 20.7701~36.9533μg/mL.%采用菌丝生长速率法测定了多菌灵、苯甲多菌灵和甲基硫菌灵3种苯并咪唑类杀菌剂对不同抗性水稻纹枯病菌(Rhizoctonia solani)的室内毒力.结果表明,多菌灵的抑菌效果最好,其对敏感菌株的EC50在0.2931~0.4035μg/mL之间,对抗性菌株的EC50在0.4147~0.6457μg/mL之间;甲基硫菌灵的毒力最低,其对敏感和抗性菌株的EC50分别在12.0397~26.5971μg/mL和20.7701~36.9533μg/mL之间.

  13. Effects of Fungicides on Aquatic Fungi and Bacteria

    Science.gov (United States)

    Conners, D. E.; Rosemond, A. D.; Black, M. C.

    2005-05-01

    Aquatic microorganisms play an important role in conditioning leaf litter that enters streams and serves as an important base of production for consumers. Contamination of streams by fungicides may adversely affect microorganisms and alter leaf litter processing rates. Unfortunately, microorganisms are rarely used in acute toxicity tests for fungicide evaluation and registration. We adapted the resazurin reduction assay, which is used in medical microbiology, to assess the acute toxicity of four fungicides (azoxystrobin, trifloxystrobin, kresoxim-methyl and chlorothalonil) to aquatic fungi (Articulospora tetracladia) and bacteria (Cytophaga spp.), and investigated the ability of the toxicants to inhibit leaf breakdown in microcosms. Fungi were more sensitive to fungicides than many standard test organisms (cladocerans, green algae, trout), while bacteria were often the least sensitive. All of the fungicides except kresoxim-methyl, when added to microcosms at concentrations that inhibited the fungi by 90 percent in acute tests, reduced leaf breakdown rates by an average of 14.7 percent. Thus, aquatic fungi and their associated functions in streams may be relatively sensitive to fungicides applied terrestrially that enter streams through non-point sources. These data highlight the importance of including aquatic fungi in safety assessments of pesticides for protection of microbial function.

  14. Resistance of Botryodiplodia theobromae to carbendazim and the fungicides screening using stem end rot of mango fruit as a control%杧果蒂腐病菌对多茵灵的抗药性测定及其杀菌剂筛选

    Institute of Scientific and Technical Information of China (English)

    胡美姣; 师超; 安勇; 李敏; 杨凤珍; 高兆银

    2009-01-01

    The resistance to carbendazim of 86 isolates of mango stem end rot pathogen Botryodiplodia theobromae Pat. collected from 3 regions in Hainan province was tested in vitro. The toxicity of 23 fungicides to 4 isolates of B. theobromae was tested by mycelium growth rate methods. The toxicity results were analyzed by the EC_(50) value, the EC_(90) value and the cross-resistance to each other. Results showed that 10 fungicides including sporgon, propiconazole, flusilazole, prochloraz, iprodi-one, difenoconazole, tebuconazole, myclobutanil, pyraclostrobin and validamycin A were recommended for choices for controlling mango stem end rot disease. In addition, the fungicides of chlorothalonil and mancozeb could also be chosen. The resistance to thiophanate-methyl, kresoxim-methyl, and diniconazole was appeared in the tested pathogens. In cross-resistance test, the results showed that carbendazim, kresoxim-methyl and diniconazole had cross-resistance each other, while kresoxim-methyl and validamycin A had negative cross-resistance each other. To avoid the resistance of the pathogen to some of the fungicides, such fungicides should be used by turns.%对来自海南3个地区的86个杧果蒂腐病菌(Botryodiplodia theobromae Pat.)菌株进行了对多菌灵的抗药性测定,结果表明,杧果蒂腐病菌群体中存在着对多菌灵抗性的群体.采用生长速率法进行了23种杀菌剂对4株杧果蒂腐病菌的室内毒力测定,通过EC_(50)值、EC_(90)值及与多菌灵的交互抗性等的综合分析,结果表明,作为防治杧果蒂腐病的首选药剂有咪鲜胺锰盐、丙环唑、氟硅唑、咪鲜胺、异菌脲、苯醚甲环唑、戊唑醇、腈菌唑、吡唑醚菌酯和井冈霉素10种杀菌剂,可选杀菌剂还有百菌清和代森锰锌.杧果蒂腐病菌除对多菌灵产生抗性外,还对甲基硫菌灵、醚菌酯和烯唑醇3种杀菌剂产生了抗药性.通过交互抗性分析,多菌灵、甲基硫菌灵和烯唑醇3

  15. Comparison of Field Efficiency with Ten Fungicides Controlling Rice Sheath Blight%10种杀菌剂防治水稻纹枯病的田间药效比较

    Institute of Scientific and Technical Information of China (English)

    宋益民; 刁亚梅; 顾春燕; 冒宇翔; 沈俊明; 陈惠; 丛国林; 马亚芳

    2012-01-01

    In order to screen excellent, low-toxic and safe fungicides for controlling rice sheath blight (Rhizoctonia solani Ktthn), the field trials of ten fungicides controlling rice sheath blight were carried out according to GB/T 17980.20-2000 and adding the efficiency of sickness plant (SPE). The results showed that the field efficiency of azoxystrobin 250 g/L SC was 87.53%. The field efficiencies of five fungicides, such as coumoxystrobin 20% SC, propiconazole 25% EC, difenoconazole 10% WG, tebuconazole 80% WP and triadimenol 15% WP, were 71.97%-79.59%. The field efficiencies of three fungicides, such as thiophanate-methyl 70% WP, validamycin 10% AS and thifluzamide 240 g/L SC, were 63.92%-66.78%.The last one was prochloraz 15% ME and its field efficiency was 46.73%. The trend of SPE and field efficiency was consistent. All ten fungicides were safe to rice plant. So azoxystrobin, coumoxystrobin, propiconazole, difenoconazole, tebuconazole and triadimenol were recommended to control rice sheath blight. Coumoxystrobin had been priority. In order to retard resistance, mixture or rotation was beneficial.%为筛选防治水稻纹枯病的高效、低毒及安全药剂,采用GB/T 17980.20 - 2000的方法,对10种杀菌剂防治水稻纹枯病的田间药效进行了试验比较,并增加调查了病株率防效,以供比较参考.结果表明,250 g/L嘧菌酯悬浮剂防治水稻纹枯病防效为87.53%,20%丁香菌酯悬浮剂、25%丙环唑乳油、10%苯醚甲环唑水分散粒剂、80%戊唑醇可湿性粉剂、15%三唑醇可湿性粉剂防效为71.97%~79.59%,70%甲基硫菌灵可湿性粉剂、10%井冈霉素水剂、240 g/L噻呋酰胺悬浮剂防效为63.92%~66.78%,15%咪鲜胺微乳剂防效为46.73%.病株率防效与病情指数防效趋势一致.试验条件下10个供试药剂对水稻无药害.防治水稻纹枯病可以选用嘧菌酯、丁香菌酯、丙环唑、苯醚甲环唑、戊唑醇、三唑醇等新型高效杀菌剂,

  16. Bacterial degradation of fungicide captan.

    Science.gov (United States)

    Megadi, Veena B; Tallur, Preeti N; Mulla, Sikandar I; Ninnekar, Harichandra Z

    2010-12-22

    The phthalimide fungicide captan has been widely used to control plant pathogenic fungi. A strain of Bacillus circulans utilized the fungicide captan as sole source of carbon and energy. The organism degraded captan by a pathway involving its initial hydrolysis to yield cis-1,2,3,6-tetrahydrophthalimide, a compound without fungicidal activity. The formation of this compound was confirmed by HPLC, IR, NMR, and mass spectral analysis. The results also revealed that cis-1,2,3,6-tetrahydrophthalimide was further degraded to o-phthalic acid by a protocatechuate pathway. These findings indicated that there was a complete mineralization of fungicide captan by B. circulans.

  17. 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.

  18. Fungicide resistance assays for fungal plant pathogens.

    Science.gov (United States)

    Secor, Gary A; Rivera, Viviana V

    2012-01-01

    Fungicide resistance assays are useful to determine if a fungal pathogen has developed resistance to a fungicide used to manage the disease it causes. Laboratory assays are used to determine loss of sensitivity, or resistance, to a fungicide and can explain fungicide failures and for developing successful fungicide recommendations in the field. Laboratory assays for fungicide resistance are conducted by measuring reductions in growth or spore germination of fungi in the presence of fungicide, or by molecular procedures. This chapter describes two techniques for measuring fungicide resistance, using the sugarbeet leaf spot fungus Cercospora beticola as a model for the protocol. Two procedures are described for fungicides from two different classes; growth reduction for triazole (sterol demethylation inhibitor; DMI) fungicides, and inhibition of spore germination for quinone outside inhibitor (QoI) fungicides.

  19. Silicato de potássio, acibenzolar-S-metil e fungicidas no controle da ferrugem da soja Potassium silicate, acibenzolar-S-methyl and fungicides on the control of soybean rust

    Directory of Open Access Journals (Sweden)

    Henrique da Silva Silveira Duarte

    2009-11-01

    ência intermediária no controle da ferrugem. O tratamento 6 foi o mais eficiente no controle da doença por resultar nos menores valores da AACPF e Ymax para os terços inferior, médio e superior, além de uma produtividade significativamente maior em relação aos demais tratamentos.Soybean production can be affected by the occurrence of several diseases. Among them, the rust, caused by the fungus Phakopsora pachyrhizi, has been outstanding. Nowadays, new strategies to control soybean rust need to be searched. Therefore, this study aimed to evaluate the efficiency of potassium silicate (KSi, acibenzolar-S-methyl and some fungicides on the control of soybean rust. An experiment was carried out under field conditions in a randomized complete block design with 10 treatments and three replications. The cultivar 'Monarca' was used because it is susceptible to rust. The treatments used were: T1 - control (plants sprayed with water; T2 - KSi (1.2kg ha-1; T3 - KSi (2.4kg ha-1; T4 - KSi (3.6kg ha-1; T5 - KSi (4.8kg ha-1; T6 - tebuconazol (125g de a.i. ha-1; T7 - potassium cloride (61.72g L-1; T8 - mancozeb (2400g de a.i. ha-1; T9 - mancozeb (2400g de a.i. ha-1 + KSi (1.2kg ha-1 and T10 - acibenzolar-S-methyl (125g de a.i. ha-1. Plants from the two lateral lines were inoculated with a suspension of 5x10(5 uredospores/mL at the V4 growth stage to produce inoculum to infect plants at the two central lines. Plants were sprayed with the products that constituted the treatments T2, T3, T4, T5, T7, T8, and T9 at V5, R1, R4, and R5.4 growth stages; and the treatments T6 and T10 at R1, R4, and R5.4 growth stages. Plants were sprayed using a costal sprayer in a volume of 200L ha-1. A total of five disease severity evaluations at the low, medium and high part of the plant canopy were done using a diagrammatic scale ranging from 0.6 to 78.5%. Data were used to calculate the area under rust progress curve (AURPC. There was no effect of the KSi rates on AURPC and final disease severity (Ymax at the

  20. Solarization and biosolarization enhance fungicide dissipation in the soil.

    Science.gov (United States)

    Fenoll, José; Ruiz, Encarnación; Hellín, Pilar; Navarro, Simón; Flores, Pilar

    2010-03-01

    Although there is some evidence regarding the effect of solarization and biosolarization on pesticide degradation, information is still scarce. The aim of this study was to determine the effect of these disinfection techniques on the degradation of eight fungicides (azoxystrobin, kresoxin methyl, tebuconazole, hexaconazole, triadimenol, cyprodinil, pyrimethanil and fludioxonil) commonly used in pepper crops under greenhouse cultivation. Seventy-five 17-L pots filled with clay-loam soil were placed in a greenhouse during the summer season and then contaminated with the studied fungicides. Treatments consisted of different disinfection treatments, including a control without disinfection, solarization and biosolarization. For the solarization and biosolarization treatments, low-density polyethylene film was used as cover. Five pots per treatment were sampled periodically up to 90d after the beginning of each treatment and fungicide residues were analyzed by GC/MS. The results showed that both solarization and biosolarization enhanced fungicide dissipation rates with regard to the control treatment, an effect which was attributed to the increased soil temperature. Most of the fungicides studied showed similar behavior under solarization and biosolarization conditions. However, triadimenol was degraded to a greater extent in the biosolarization than in the solarization treatment, while fludioxonil behaved in the opposite way. The results confirm that both solarization and biosolarization contribute to pesticide dissipation and can therefore be considered alongside other soil disinfection techniques, as a bioremediation tool for pesticide-polluted soils.

  1. Desorption and mobilization of three strobilurin fungicides in three types of soil.

    Science.gov (United States)

    Wu, Ping; Wu, Wen Zhu; Han, Zhi Hua; Yang, Hong

    2016-06-01

    Phenamacril (JS399-19 with independent intellectual property developed by China), azoxystrobin, and kresoxim-methyl are strobilurin fungicide. Due to their broad spectrum and good control of most of known fungi, strobilurin fungicide has been widely used in agriculture management. Thus, it is important to evaluate their environmental behaviors particularly in soils and underground water. In this study, the sorption/desorption and mobility of strobilurin fungicides in three Chinese soils (Jiangxi red soil, Taihu paddy soil, and Northeast China black soil) were conducted using comprehensively analytic approaches including batch experiment and soil thin-layer chromatography. The strobilurin fungicides were hard to be adsorbed in Jiangxi red soil but had medium adsorption capability in Tanhu paddy soil and Northeast China black soil, while the desorption of three strobilurin fungicides ranked in the order of Jiangxi red soil > Taihu paddy soil > Northeast China black soil. Soil properties including soil organic matter (SOM), pH, and cationic exchange capacity (CEC) affected the adsorption/desorption of the fungicides. Azoxystrobin and kresoxim-methyl had weak mobility in the soils. JS399-19 was moderately mobile in Jiangxi red soil but was not easily moved in Taihu paddy soil and Northeast China black soil. Due to their weak mobility in soils, these strobilurin fungicides tended to remain in the soil phase but not to shift downward to underground water. As azoxystrobin and JS399-19 had a long retention period in soil, there may become persistent residues in the soil environment.

  2. 5种药剂对油茶炭疽病的防治效果研究%Control Effects of 5 Fungicides against Anthracnose of Camellia oleifera

    Institute of Scientific and Technical Information of China (English)

    邓鑫州; 黄连桂; 邓荫伟

    2011-01-01

    [目的]研究5种药剂对油茶炭疽病的防治效果,以筛选出能有效防治油茶炭疽病的杀菌剂.[方法]测定了1%波尔多液、50%多菌灵500倍液、75%百菌清600倍液、80%代森锰锌700倍液和70%甲基硫菌灵800倍液对油茶炭疽病的防治效果.[结果]1%波尔多液和80%代森锰锌的防治效果达75.00%,50%多菌灵和75%百菌清的防效为69.14%;70%甲基硫菌灵的防效欠佳,仅为14.81%,与其他4种药剂存在极显著差异;1%波尔多液喷施后,药剂在叶片上的附着期长,防治效果最好.[结论]1%波尔多液是防治油茶炭疽病的最佳方案.%[ Objective J The aim was to study the study control effects of 5 fungicides against anthracnose of Camellia oleifera so as to screen out some fungicides which could control anthracnose of Camellia oleifera effectively. [ Method ] Control effects of 5 fungicides like 1 % Bordeaux, 50% Carbendazim of 500 times, 75% Chlorothalonil of 600 times, 80% Mancozebhad of 700 times and 70% Thiophanate of 800 times against anthracnose of Camellia oleifera were determined. [ Result] Control effects of 1% Bordeaux and 80% Mancozebhad of 700 times against anthracnose of Camellia oleifera reached 75. 00%. Control effects of 50% Carbendazim of 500 times and 75% Chlorothalonil of 600 times reached 69. 14%.70% Thiophanate of 800 times had had control effect (14. 18% ) against anthracnose of Camellia oleifera, furthermore it had very significant difference compared with the former 4 fungicides. 1 % Bordeaux had a long attachment time on the leaves and had a good control effect. [ Conclusion ] 1 % Bordeaux is the optimal fungicide to control anthracnose of Camellia oleifera.

  3. Ketahanan Beberapa Jamur Patogen terhadap Fungisida

    Directory of Open Access Journals (Sweden)

    Christanti Sumardiyono

    1995-12-01

    Full Text Available Chemical control of plant pathogens have been done for a long time using contact and systemic fungicides. Resistance of the pathogens to fungicides may caused failure of disease control program. Studies by in vitro, in green house and fields were done at Yogyakarta to know the fungal which were resistant to several fungicides after treatment. The pathogen tested to fungicides were Colletotrichum capsici on red pepper to propineb, mancozeb, mixture of carbendazim and mancozeb, and thiophanate methyl, Alternaria porri on garlic to thiophanate methyl, Phytophthora palmivora on cocoa to Al-fosetyl, metalaxyl, mancozeb, and Copper Oxychloride, and Peronosclerospora maydis on corn to metalaxyl. The study indicated that C. capsici was resistant to propineb, mancozeb, and mixture of carbendazim and mancozeb, but sensitive to thiophanate methyl. A. porri from plant treated with thiophanate methyl indicated resistant to the fungicides. ED50 of Al-fosetyl and metalaxyl on P. palmivora were higher than on mancozeb and copper oxychloride, so that it was resistance strain. Key words: contact fungicides, systemic fungicides, resistance

  4. Chiral separation of agricultural fungicides.

    Science.gov (United States)

    Pérez-Fernández, Virginia; García, Maria Ángeles; Marina, Maria Luisa

    2011-09-23

    Fungicides are very important and diverse environmental and agricultural concern species. Their determination in commercial formulations or environmental matrices, requires highly efficient, selective and sensitive methods. A significant number of these chemicals are chiral with the activity residing usually in one of the enantiomers. The different toxicological and degradation behavior observed in many cases for fungicide enantiomers, results in the need to investigate them separately. For this purpose, separation techniques such as GC, HPLC, supercritical fluid chromatography (SFC) and CE have widely been employed although, at present, HPLC still dominates chromatographic chiral analysis of fungicides. This review covers the literature concerning the enantiomeric separation of fungicides usually employed in agriculture grouping the chiral separation methodologies developed for their analysis in environmental, biological, and food samples.

  5. Review of strobilurin fungicide chemicals.

    Science.gov (United States)

    Balba, Hamdy

    2007-05-01

    Strobilurins are natural products isolated and identified from specific fungi. Natural strobilurins were named in the order of their discovery as strobilurin-A followed by strobilurin-B, C, D etc. Their discovery opened the door for new chemistry of synthetic fungicides. Applying Quantitative Structural Activity Relationship (QSAR) on the structures of the natural strobilurins, many pesticide companies were able to discover many synthetic analogues that are more efficacious and more stable fungicides. At present there are about eight synthetic strobilurins in the fungicides worldwide market. Some of these products are worldwide registered for use as agrochemical and some are in the process of registration. This class of fungicides is relatively new, as crop protection products and information about them is still fairly scarce. In this review, syntheses and chemistry of natural and synthetic strobilurins are discussed. Also, the mode of action, efficacy, biotic/abiotic degradation, analytical methods, and agricultural uses are discussed.

  6. Fungicidal preparations from Inula viscose

    OpenAIRE

    2002-01-01

    Inula viscosa is a perennial plant native to the Mediterranean Basin. Extracts made from the shoots of this plant exhibited a strong fungicidal activity in vitro and in vivo. TLC analyses revealed at least 7 fungicidal compounds. Most are lipophilic. When such extracts were sprayed on the leaf surface of crop plants they effectively controlled downy mildew in grape, cucumber and tabacco; late blight in potato and tomato; gray mold in cucumber and tomato; and, powdery mildew in cucurbits and c...

  7. Comparison on the Control Effects of Different Fungicides on Postharvest Citrus Green Mould%不同杀菌剂对采后柑桔绿霉病的防治效果比较

    Institute of Scientific and Technical Information of China (English)

    夏长秀; 李红叶; 王明爽; 彭龙; 娄伟; 严翔; 赖华荣; 凌永河; 朱从一; 方贻文

    2012-01-01

    在柑桔果实先刺伤接种柑桔绿霉病菌Penicillium digitatum孢子悬浮液再进行药剂浸果的条件下,研究了不同类型、不同浓度药剂对抗苯并咪唑类和咪唑类杀菌剂(双抗)或双敏感菌系的防治效果.结果表明:500或1 000 mg/L的甲基硫菌灵、咪鲜胺(扑霉灵)和抑霉唑(500mg/L)单剂,甲基硫菌灵和咪鲜胺(或扑霉灵)混剂对双抗菌系防治作用均低于50%;1 000 mg/L百可得单剂,500、1 000 mg/L百可得混配相同浓度咪鲜胺(或扑霉灵)均可控制双抗菌系引起的腐烂,防治效果在83%以上;1000mg/L咯菌腈对双抗菌系的防治效果为83.3%,500和1 000 mg/L嘧霉胺对双抗菌系的防治效果分别为91.1%和98.9%.500mg/L百可得、抑霉唑和嘧霉胺单剂,500mg/L百可得混配相同浓度咪鲜胺(或扑霉灵),500 mg/L甲基硫菌灵混配相同浓度扑霉灵对敏感菌系均有88%以上防治效果.基于研究结果,建议不再使用苯并咪唑类和咪唑类杀菌剂单剂或这两类杀菌剂混剂防治柑桔采后病害,可选择1 000 mg/L百可得(双胍辛烷苯基磺酸盐)单剂,500mg/L百可得和相同浓度咪唑类混剂.同时建议将嘧霉胺登记用于柑桔采后处理.%Effects of different types and concentrations of fungicides on post-harvest green mould disease were evaluated after wound- inoculation of the fruit with spore suspensions of Penicillium digitatum. Results showed that the control efficacy of 500 or 1 000 mg/L of thiophanate-methyl, 500 or 1 000 mg/L of prochlorazalone, 500 mg/L of imazalil, 500 mg/L of thiophanate-methyl plus 500 mg/L of prochloraz was lower than 50%. However, 1 000 mg/L of Bellkute, 500 mg/L of Bellkute + 500 mg/L of Prochloraz, 1 000 mg/L of Bellkute + 1 000 mg/L of Prochloraz showed good control results toward the double resistance isolates. The control efficacy of fludioxonil at 1 000 mg/L, pyrimethanil at 500 and 1 000 mg/L was 83. 3%, 91. 1% and 98. 9%, respectively. The control efficacy

  8. A novel bioassay to monitor fungicide sensitivity in Mycosphaerella fijiensis.

    Science.gov (United States)

    Ngando, Josué E; Rieux, Adrien; Nguidjo, Oscar; Pignolet, Luc; Dubois, Cécile; Mehl, Andreas; Zapater, Marie-Françoise; Carlier, Jean; de Lapeyre de Bellaire, Luc

    2015-03-01

    Black leaf streak disease (BLSD) is the most important disease of bananas for export. The successful control of BLSD requires an intensive use of systemic fungicides, leading to the build-up of resistance and failure of control. Early detection of fungicide resistance is crucial to drive rational chemical strategies. Present methods relying on ascospore germination bioassays have several drawbacks that could be overcome using conidia. Generally, a single genotype is present on the conidial population derived from one lesion. Conidial germination tests with thiabendazole (5 mg L(-1)) enable a clear detection of strains resistant to methyl benzimidazole carbamates. Germination bioassays on azoxystrobin (10 mg L(-1)) enable the detection of most QoI-resistant strains, but their proportion might be underestimated with cut-off limits of germ tube length (L > 120 µm) or growth inhibition (GI < 50%). The level of fungicide resistance differs at different canopy levels of a banana tree, which should be considered for sampling. The ascospore germination bioassay provided more variable estimations of the level of resistance by comparison with the new conidial germination bioassay. Germination bioassays performed with conidia obtained from young lesions overcome most drawbacks encountered with ascospore germination bioassays and could be considered as a new reference method for fungicide resistance monitoring in this species. Different steps are proposed, from sampling to microscopic examinations, for the implementation of this technique. © 2014 Society of Chemical Industry.

  9. Resistance of melon powdery mildew isolates to kresoxim-methyl in Guangxi and determination of its sensitivity to three fungicides%广西瓜类白粉病菌对醚菌酯的抗药性及其对3种药剂的敏感性检测

    Institute of Scientific and Technical Information of China (English)

    林珊宇; 朱桂宁; 颜梅新; 贤小勇

    2014-01-01

    [Objective]The resistance level, distribution and development of melon powdery mildew isolates to kresoxim-methyl in Guangxi were identified and effective alternative fungicides were screened to provide references for prevention and controlling of melon powdery mildew. [Method]From 2007 to 2012, bitter gourd, wax gourd, muskmelon, cucumber and bottle gourd disease samples were collected from Nanning, Guiping, and Beihai, etc. Their isolates’ resistance to kresoxim-methyl were detected by leaf disk tests. Sensitivity of high-resistant isolates to carbendazim, trifloxystrobin and propineb were also analyzed. [Result]The results showed that 83 melon powdery mildew population produced resistance to kresoxim-methyl in varying degrees. Resistant isolates were mainly distributed in bitter gourd powdery mildew and their resistant fre-quency was the highest (63.89%), while bottle gourd isolates had the lowest resistant frequency (6.67%). The resistant level of bitter gourd powdery mildew against to kresoxim-methyl increased gradually from 2007 to 2012 in Nanning City, resulting in development of high-resistance population. Fungicide screening assay results indicated that powdery mildew isolates with highly resistant to kresoxim-methyl, were highly drug-fast to carbendazim and cross-resistant to trifloxystrobin, but was sensi-tive to propineb. [Conclusion]In Guangxi, melon powdery mildew isolates were highly resistant to kresoxim-methyl and al-ternate use of propineb in the production process could be recommended.%【目的】了解广西瓜类白粉病菌对醚菌酯的抗性水平、抗性菌株的分布和发展趋势,并筛选瓜类白粉病防治药剂,为瓜类白粉病的抗性预防及防治提供参考。【方法】2007~2012年从广西南宁、桂平、北海等地采集苦瓜、冬瓜、甜瓜、黄瓜和葫芦瓜白粉病菌样品,采用叶碟保湿培养法检测供试菌株对醚菌酯的抗药性,并选取高抗菌株测定其对多菌灵、肟菌

  10. Genetics of fungal resistance to systemic fungicides

    NARCIS (Netherlands)

    Tuyl, van J.M.

    1977-01-01

    Since the introduction of the systemic fungicides, fungicide resistance has become a serious problem in plant disease control. This study was carried out in order to contribute to the knowledge about the genetics of fungal resistance to fungicides both from a practical and a fundamental point of vie

  11. 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...... and reproducibility were within the limits for repeatability and reproducibility given by the Horwitz equation. Validation was not accepted for azoxystrobin in grapes on all three detectors and for azoxystrobin in apple for the MS-detector. A comparison of matrix-matched standards versus standards in solvent showed...

  12. 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...

  13. Fungicides Screening for Controlling Wheat Scab%防治小麦赤霉病的药剂筛选

    Institute of Scientific and Technical Information of China (English)

    马亚芳; 施娟娟; 倪龙博; 马聪; 倪珏萍

    2015-01-01

    In order to choose fungicide reasonably for controlling wheat scab, nine fungicides and nine formulations were tested by bioassay and field trials, respectively. The mycelium growth rate method was used in vitro and spray method was used in field pot. Bioassay results showed that EC50 values of nine fungicides were 0.0411-0.5863 mg/L, the activity of prochloraz-Cu was the highest, and the activity of carbendazim was the lowest. Field results showed that control effects of carbendazim 50% WP 750.0-1125.0 g/hm2, phenamacril 25% SC 375.0-750.0 g/hm2, prochloraz 450 g/L EW 168.8-236.3 g/hm2, tebuconazole 80% WP 75.0-125.0 g/hm2 were 76.11%-90.78%, 85.49%-97.37%, 75.43%- 88.57%, 76.11%-89.59%. The control effects of phenamacril + hexaconazole 20% SC 240.0-420.0 g/hm2, phenamacril + tebuconazole 48% SC 240.0-420.0 g/hm2, tebuconazole + carbendazim 40% SC 300.0-420.0 g/hm2, tebuconazole + prochloraz 40% SC 150.0-210.0 g/hm2, and thiophanate-methyl + tebuconazole 48% SC 216.0-432.0 g/hm2 were 93.22%-98.62%, 91.57%-99.67%, 66.89%-86.52%, 74.91%-87.37%, and 71.67%-85.32%. The control effects of all five mixture were better than corresponding single formulation and carbendazim formulation. Tebuconazole, prochloraz, phenamacril, phenamacril +tebuconazole 48% SC, and tebuconazole + prochloraz 40% SC were effective to control wheat scab.%以小麦赤霉病为靶标,研究比较了9种原药的室内活性和9种制剂的田间防效,为选择田间用药提供科学依据。室内活性采用菌丝生长速率法,田间防效采用喷雾法。室内生物活性结果表明:9种原药对小麦赤霉病的EC50为0.0411~0.5863 mg/L,其中咪鲜胺铜盐活性最高,多菌灵活性最低。田间药效结果表明:50%多菌灵WP 750.0~1125.0 g/hm2(有效成分用量,下同)防效为76.11%~90.78%,25%氰烯菌酯SC 375.0~750.0 g/hm2防效为85.49%~97.37%,450 g/L咪鲜胺EW 168.8~236.3 g/hm2防效为75.43%~88.57%,80%戊唑醇WP 75.0~125.0 g/hm2

  14. Mixtures as a fungicide resistance management tactic.

    Science.gov (United States)

    van den Bosch, Frank; Paveley, Neil; van den Berg, Femke; Hobbelen, Peter; Oliver, Richard

    2014-12-01

    We have reviewed the experimental and modeling evidence on the use of mixtures of fungicides of differing modes of action as a resistance management tactic. The evidence supports the following conclusions. 1. Adding a mixing partner to a fungicide that is at-risk of resistance (without lowering the dose of the at-risk fungicide) reduces the rate of selection for fungicide resistance. This holds for the use of mixing partner fungicides that have either multi-site or single-site modes of action. The resulting predicted increase in the effective life of the at-risk fungicide can be large enough to be of practical relevance. The more effective the mixing partner (due to inherent activity and/or dose), the larger the reduction in selection and the larger the increase in effective life of the at-risk fungicide. 2. Adding a mixing partner while lowering the dose of the at-risk fungicide reduces the selection for fungicide resistance, without compromising effective disease control. The very few studies existing suggest that the reduction in selection is more sensitive to lowering the dose of the at-risk fungicide than to increasing the dose of the mixing partner. 3. Although there are very few studies, the existing evidence suggests that mixing two at-risk fungicides is also a useful resistance management tactic. The aspects that have received too little attention to draw generic conclusions about the effectiveness of fungicide mixtures as resistance management strategies are as follows: (i) the relative effect of the dose of the two mixing partners on selection for fungicide resistance, (ii) the effect of mixing on the effective life of a fungicide (the time from introduction of the fungicide mode of action to the time point where the fungicide can no longer maintain effective disease control), (iii) polygenically determined resistance, (iv) mixtures of two at-risk fungicides, (v) the emergence phase of resistance evolution and the effects of mixtures during this phase

  15. 1978 Suggested Fungicide Guide: Fungicide Guide for Commercial Vegetable Growers. Circular 999.

    Science.gov (United States)

    Jacobsen, Barry; Shurtleff, M. C.

    This circular lists suggested uses of insecticides and fungicides for the control of pests and disease by commercial vegetable growers. Suggestions are given for selection, dosage and application of fungicides to control infestation in all crops of commercial importance. (CS)

  16. Synthesis, Crystal Structure and Fungicidal Activity of 3- ( 4- Chloro- 3- ethyl- 1 -methyl- 1 H- pyrazol- 5-yl ) - 6- (E) phenylvinyltriazolo [ 3, 4-b ] - 1,3, 4-thiadiazole

    Institute of Scientific and Technical Information of China (English)

    陈寒松; 李正名; 杨小平; 王宏根; 姚心侃

    2000-01-01

    The crystal structure of the title compound 3-(4-Chloro-3-ethyl-1-methyl-1H-pyrazol-5-yl)-6- (E) phenylvinyltriazolo [ 3, 4-b ]-1, 3, 4-thiadiazole ( C17 H15ClN6S, Mr = 370.87) was determined by single crystal X-ray diffraction. The crystal ismonoclinic, space group P21/n, a = 10.862(2), b = 11.541(2), c = 14.994(3) A,β=108.41(3)°, V=1783(1) A, Z=4, Dx =1.381g/cm-3, μ=0.3361 mm-1, andF(000) = 768. The results confirmed that the title compound belongs to type E of ste-reochemistry. The dihedral angle between triazole and 1, 3, 4-thiadiaole ring is 3° andthe torsion angle between 1,3, 4-thiadiazole and pyrazole ring is 134.0°.

  17. Adjuvants for spraying of fungicides in wheat

    OpenAIRE

    2014-01-01

    The foliar diseases and spike can markedly reduce the yield of wheat. Despite prevailing chemical control in the management of disease, studies with adjuvants to improve the performance of fungicides are still incipient. The aim of this study was to evaluate the effect of adding adjuvants to chemical fungicides to control leaf diseases and spike, as well as on the yield of wheat crop. The experimental design was a randomized block design with 05 treatments: control (no fungicide application i...

  18. PROS AND CONS OF FUNGICIDES: AN OVERVIEW

    OpenAIRE

    Anju Rani*, Raj Singh, Permod Kumar, Gyanika Shukla

    2017-01-01

    Many contact and systemic fungicides are used to control plant pathogens to get disease free crop. Farmers use these chemicals to protect their crop like plantation crop, fiber crop, vegetable and fruit crops etc., from plant pathogenic fungi and their toxins which destroy their entire crop and finally economic loss occurred. But these fungicides also affect soil microorganisms like decomposers and mycorrhizal fungi etc. Fungicides also show hazardous affect on human health. Soil and water po...

  19. Bridging the gaps between scientific literature and grower perceptions of trunk disease management

    Science.gov (United States)

    Trunk diseases significantly limit the productivity of California vineyards. Field trials have shown three practices to minimize infection of pruning wounds: delayed pruning, double pruning, and the fungicide thiophanate-methyl (Topsin M). For optimal efficacy, such preventative practices must be a...

  20. Can high-risk fungicides be used in mixtures without selecting for fungicide resistance?

    Science.gov (United States)

    Mikaberidze, Alexey; McDonald, Bruce A; Bonhoeffer, Sebastian

    2014-04-01

    Fungicide mixtures produced by the agrochemical industry often contain low-risk fungicides, to which fungal pathogens are fully sensitive, together with high-risk fungicides known to be prone to fungicide resistance. Can these mixtures provide adequate disease control while minimizing the risk for the development of resistance? We present a population dynamics model to address this question. We found that the fitness cost of resistance is a crucial parameter to determine the outcome of competition between the sensitive and resistant pathogen strains and to assess the usefulness of a mixture. If fitness costs are absent, then the use of the high-risk fungicide in a mixture selects for resistance and the fungicide eventually becomes nonfunctional. If there is a cost of resistance, then an optimal ratio of fungicides in the mixture can be found, at which selection for resistance is expected to vanish and the level of disease control can be optimized.

  1. 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.

  2. The emergence of resistance to fungicides.

    Science.gov (United States)

    Hobbelen, Peter H F; Paveley, Neil D; van den Bosch, Frank

    2014-01-01

    Many studies exist about the selection phase of fungicide resistance evolution, where a resistant strain is present in a pathogen population and is differentially selected for by the application of fungicides. The emergence phase of the evolution of fungicide resistance--where the resistant strain is not present in the population and has to arise through mutation and subsequently invade the population--has not been studied to date. Here, we derive a model which describes the emergence of resistance in pathogen populations of crops. There are several important examples where a single mutation, affecting binding of a fungicide with the target protein, shifts the sensitivity phenotype of the resistant strain to such an extent that it cannot be controlled effectively ('qualitative' or 'single-step' resistance). The model was parameterized for this scenario for Mycosphaerella graminicola on winter wheat and used to evaluate the effect of fungicide dose rate on the time to emergence of resistance for a range of mutation probabilities, fitness costs of resistance and sensitivity levels of the resistant strain. We also evaluated the usefulness of mixing two fungicides of differing modes of action for delaying the emergence of resistance. The results suggest that it is unlikely that a resistant strain will already have emerged when a fungicide with a new mode of action is introduced. Hence, 'anti-emergence' strategies should be identified and implemented. For all simulated scenarios, the median emergence time of a resistant strain was affected little by changing the dose rate applied, within the range of doses typically used on commercial crops. Mixing a single-site acting fungicide with a multi-site acting fungicide delayed the emergence of resistance to the single-site component. Combining the findings with previous work on the selection phase will enable us to develop more efficient anti-resistance strategies.

  3. Agrochemical synergism imposes higher risk to Neotropical bees than to honeybees

    Science.gov (United States)

    Tomé, Hudson V. V.; Ramos, Gabryele S.; Araújo, Micaele F.; Santana, Weyder C.; Santos, Gil R.; Guedes, Raul Narciso C.; Maciel, Carlos D.; Newland, Philip L.

    2017-01-01

    Bees are key pollinators whose population numbers are declining, in part, owing to the effects of different stressors such as insecticides and fungicides. We have analysed the susceptibility of the Africanized honeybee, Apis mellifera, and the stingless bee, Partamona helleri, to commercial formulations of the insecticides deltamethrin and imidacloprid. The toxicity of fungicides based on thiophanate-methyl and chlorothalonil were investigated individually and in combination, and with the insecticides. Results showed that stingless bees were more susceptible to insecticides than honeybees. The commercial fungicides thiophanate-methyl or chlorothalonil caused low mortality, regardless of concentration; however, their combination was as toxic as imidacloprid to both species, and over 400-fold more toxic than deltamethrin for A. mellifera. There were highly synergistic effects on mortality caused by interactions in the mixture of imidacloprid and the fungicides thiophanate-methyl, chlorothalonil and the combined fungicide formulation in A. mellifera, and also to a lesser extent in P. helleri. By contrast, mixtures of the deltamethrin and the combined fungicide formulation induced high synergy in P. helleri, but had little effect on the mortality of A. mellifera. Differences in physiology and modes of action of agrochemicals are discussed as key factors underlying the differences in susceptibility to agrochemicals. PMID:28280585

  4. Recent Trends in Studies on Botanical Fungicides in Agriculture

    OpenAIRE

    Mi-Young Yoon; Byeongjin Cha; Jin-Cheol Kim

    2013-01-01

    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...

  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.

  6. Phenolic compounds and antioxidant activity of red wine made from grapes treated with different fungicides.

    Science.gov (United States)

    Mulero, J; Martínez, G; Oliva, J; Cermeño, S; Cayuela, J M; Zafrilla, P; Martínez-Cachá, A; Barba, A

    2015-08-01

    The effect of treating grapes with six fungicides, applied under critical agricultural practices (CAP) on levels of phenolic compounds and antioxidant activity of red wines of Monastrell variety was studied. Vinifications were performed through addition of active dry yeast (ADY). Measurement of phenolic compounds was made with HPLC-DAD. Determination of antioxidant activity was through reaction of the wine sample with the DPPH radical. The wine prepared from grapes treated with quinoxyfen shows a greater increase of phenolic compounds than the control wine. In contrast, the wine obtained from grapes treated with trifloxystrobin showed lower total concentration of phenolic compounds, including stilbenes, whilst treatments with kresoxim-methyl, fluquinconazole, and famoxadone slightly reduced their content. Hence, the use of these last four fungicides could cause a decrease in possible health benefits to consumers. Antioxidant activity hardly varied in the assays with quinoxyfen, fluquinconazole and famoxadone, and decreased in the other wines.

  7. 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...

  8. Fungicide and insecticide residues in rice grains

    Directory of Open Access Journals (Sweden)

    Gustavo Mack Teló

    2017-01-01

    Full Text Available The objective of this study was to analyse residues of fungicides and insecticides in rice grains that were subjected to different forms of processing. Field work was conducted during three crop seasons, and fungicides and insecticides were applied at different crop growth stages on the aerial portion of the rice plants. Azoxystrobin, difenoconazole, propiconazole, tebuconazole, and trifloxystrobin fungicides were sprayed only once at the R2 growth stage or twice at the R2 and R4 growth stages; cypermethrin, lambda-cyhalothrin, permethrin, and thiamethoxam insecticides were sprayed at the R2 growth stage; and permethrin was sprayed at 5-day intervals from the R4 growth stage up to one day prior to harvest. Pesticide residues were analysed in uncooked, cooked, parboiled, polished and brown rice grains as well as rice hulls during the three crop seasons, for a total of 1458 samples. The samples were analysed by gas chromatography with electron capture detection (GC-ECD using modified QuEChERS as the extraction method. No fungicide or insecticide residues were detected in rice grain samples; however, azoxystrobin and cypermethrin residues were detected in rice hull samples.

  9. The 1975 Insecticide, Herbicide, Fungicide Quick Guide.

    Science.gov (United States)

    Page, Bill G.; Thomson, W. T.

    This is a quick guide for choosing a chemical to use to control a certain pest on a specific crop. Information in the book was obtained from manufacturers' labels and from the USDA and FDA pesticide summary. The book is divided into four parts: (1) insecticides, (2) herbicides, (3) fungicides, and (4) conversion tables. Each of the first three…

  10. USE OF THE FUNGICIDE CARBENDAZIM AS A MODEL COMPOUND TO DETERMINE THE IMPACT OF ACUTE CHEMICAL EXPOSURE DURING OOCYTE MATURATION AND FERTILIZATION ON PREGNANCY OUTCOME IN THE HAMSTER

    Science.gov (United States)

    Here we use a hamster animal model to identify early pregnancy loss due to an acute chemical exposure to the female during the perifertilization interval. The fungicide carbendazim (methyl 1H-benzimidazole-2-carbamate), a microtubule poison with antimitotic activity, was selected...

  11. Delaying selection for fungicide insensitivity by mixing fungicides at a low and high risk of resistance development: a modeling analysis.

    Science.gov (United States)

    Hobbelen, P H F; Paveley, N D; van den Bosch, F

    2011-10-01

    This study used mathematical modeling to predict whether mixtures of a high-resistance-risk and a low-risk fungicide delay selection for resistance against the high-risk fungicide. We used the winter wheat and Mycosphaerella graminicola host-pathogen system as an example, with a quinone outside inhibitor fungicide as the high-risk and chlorothalonil as the low-risk fungicide. The usefulness of the mixing strategy was measured as the "effective life": the number of seasons that the disease-induced reduction of the integral of canopy green area index during the yield forming period could be kept fungicides, (ii) was constant for the low-risk fungicide but could increase for the high-risk fungicide, and (iii) was adjusted for both fungicides but their ratio in the mixture was fixed. The effective life was highest when applying the full label-recommended dose of the low-risk fungicide and adjusting the dose of the high-risk fungicide each season to the level required to maintain effective control. This strategy resulted in a predicted effective life of ≤ 12 years compared with 3 to 4 years when using the high risk fungicide alone.

  12. Field evaluation of fungicides in controlling chickpea Ascochyta blight in Washington, 2011

    Science.gov (United States)

    Field evaluation of five fungicides of different fungicide classes showed that the fungicides can reduce disease severity and increase yield of chickpea. Alternative fungicides to traditional strobilurin fungicides were identified, and can be used to prevent development of strobilurin resistance in...

  13. 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 catchment and the plot scales enable to evaluate the sources areas of pesticide off-site transport.

  14. Can agricultural fungicides accelerate the discovery of human antifungal drugs?

    Science.gov (United States)

    Myung, Kyung; Klittich, Carla J R

    2015-01-01

    Twelve drugs from four chemical classes are currently available for treatment of systemic fungal infections in humans. By contrast, more than 100 structurally distinct compounds from over 30 chemical classes have been developed as agricultural fungicides, and these fungicides target many modes of action not represented among human antifungal drugs. In this article we introduce the diverse aspects of agricultural fungicides and compare them with human antifungal drugs. We propose that the information gained from the development of agricultural fungicides can be applied to the discovery of new mechanisms of action and new antifungal agents for the management of human fungal infections.

  15. 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.

  16. 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.

  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. A model for fungicide applications in winter wheat

    DEFF Research Database (Denmark)

    Ørum, Jens Erik; Pinnschmidt, Hans; Jørgensen, Lise Nistrup

    2006-01-01

    A statistical prediction of the opitamal fungicide dose and strategy based on expert knowledge and 5 yers' trial data from Denmark......A statistical prediction of the opitamal fungicide dose and strategy based on expert knowledge and 5 yers' trial data from Denmark...

  19. Synthesis and Fungicidal Activities of Pyrimethanil Heterocyclic Acid Salt

    Institute of Scientific and Technical Information of China (English)

    SUN,Xiao-Hong; LIU,Yuan-Fa; CHEN,Bang; JIA,Ying-Qi; YANG,Jian-Wu

    2007-01-01

    Seven pyrimethanil salts were synthesized by organic base containing nitrogen atom reacting with substituted pyridine acids. They are reported for the first time. Their structures have been confirmed by IR, 1H NMR and elemental analysis. The preliminary toxicity tests indicated that most of them exhibited excellent fungicidal activities.The relationship between the structures and the fungicidal activities of the compounds was discussed.

  20. 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 pullulan

  1. Chemical control of anthrachnose of Sansevieria trisfasciata var. Hahnii on a detached-leaf system.

    Directory of Open Access Journals (Sweden)

    Gerardo Pérez-León

    2015-06-01

    Full Text Available The objective of this work was to assess fungicides to combat Sansevieria trifasciata var. Hahnii anthracnose. Twelve fungicides (alone or in mixture were evaluated on the infection and severity of C. sansevieriae on a detached- leaf system. Fungicides used were azoxystrobin, boscalid + pyraclostrobin, carbendazim + mancozeb, difenoconazole, epoxiconazole + carbendazim, folpet, imazalil, thiophanate-methyl + mancozeb, myclobutanil, and prochloraz. The study was carried out at the Plant Biotechnology Laboratory of the Agricultural Research Center of the University of Costa Rica, during the first semester of 2012. Each chemical treatment was applied by aspersion on the day of inoculation (0 dai or three days after it (3 dai. The number and diameter of the lesions were evaluated after seven, eleven and fifteen dai. Fungicide, application moment, fungicide x application moment interaction and fungicide x evaluation moment interaction significantly affected (p<0,0001 both evaluated variables. Azoxystrobin, boscalid + pyraclostrobin, carbendazim + mancozeb, epoxiconazole + carbendazim and thiophanate-methyl + mancozeb provided 100% protection to Sansevieria leaves throughout the evaluation period (15 days when applied the same day of inoculation (0 dai. After three days of inoculation (3 dai only epoxiconazole + carbendazim completely inhibited the pathogen establishment (zero incidence in the three evaluations when applied azoxystrobin and carbendazim + mancozeb, the incidence was 0% after seven and eleven days for the first treatment and after seven days for the second one.

  2. A rapid resazurin bioassay for assessing the toxicity of fungicides.

    Science.gov (United States)

    Fai, Patricia Bi; Grant, Alastair

    2009-03-01

    Fungicides are widely used in agriculture, and released in large amounts to the environment. Methods used for antifungal susceptibility testing are cumbersome and time-consuming. As a result, very little attention has been paid to including fungal tests in the routine screening of pesticides and there are no reports in the literature of fungicide focussed effects directed analysis (EDA). In addition very little is known on the toxicity of fungicides to environmentally significant fungi. Here we report a rapid microplate-based resorufin fluorescence inhibition bioassay and compare it with a 24h microplate-based yeast growth inhibition bioassay using eight fungicides. The growth inhibition bioassay was sensitive, giving IC50 and IC90 values comparable to previously reported IC50 or MICs of these fungicides for Saccharomyces cerevisiae and other fungi. The resorufin fluorescence inhibition bioassay was both faster and more sensitive than the growth inhibition bioassay. Inhibitory concentrations obtained just after 30min of incubation with amphotericin B (AMB) and captan were at least a hundred fold lower than IC50s in the literature for fungi. The fluorescence bioassay showed only a small response to pyrazophos and thiabendazole but these only inhibited growth at high concentrations so this may reflect low sensitivity of S. cerevisiae to these particular fungicides. This bioassay can detect toxic effects of a range of fungicides from different chemical classes with different modes of action. It will be valuable for screening chemical libraries for fungicides and as a biomarker for detecting the effects of fungicides to non-target fungi.

  3. Chemosensitization of plant pathogenic fungi to agricultural fungicides.

    Directory of Open Access Journals (Sweden)

    Vitaly eDzhavakhiya

    2012-03-01

    Full Text Available A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or chemosensitization. Chemosensitization can be accomplished by combining a commercial fungicide with a certain non- or marginally fungicidal substance at levels where, alone, neither compound would be effective. Chemosensitization decreases the probability of the pathogen developing resistance, reduces the toxic impact on the environment by lowering effective dosage levels of toxic fungicides, and improves efficacy of antifungal agents. The present study shows that the antifungal activity of azole and strobilurin fungicides can be significantly enhanced through their co-application with certain natural or synthetic products against several economically important plant pathogenic fungi. Quadris (azoxystrobin combined with thymol at a non-fungitoxic concentration produced much higher growth inhibition of Bipolaris sorokiniana, Phoma glomerata, Alternaria sp. and Stagonospora nodorum than the fungicide alone. The effect of Dividend (difenoconazole applied with thymol significantly enhanced antifungal activity against B. sorokiniana and S. nodorum. Folicur (tebuconazole combined with 4-hydroxybenzaldehyde (4-HBA, 2,3-dihydroxybenzaldehyde or thymol significantly inhibited growth of A. alternata, at a much greater level than the fungicide alone. In addition, co-application of Folicur and 4-HBA resulted in a similar enhancement of antifungal activity against Fusarium culmorum. Lastly, we discovered that metabolites in the culture liquid of F. sambucinum biocontrol isolate FS-94 also had chemosensitizing activity, increasing S. nodorum sensitivity to Folicur and Dividend.

  4. Chemosensitization of plant pathogenic fungi to agricultural fungicides.

    Science.gov (United States)

    Dzhavakhiya, Vitaly; Shcherbakova, Larisa; Semina, Yulia; Zhemchuzhina, Natalia; Campbell, Bruce

    2012-01-01

    A common consequence of using agricultural fungicides is the development of resistance by fungal pathogens, which undermines reliability of fungicidal effectiveness. A potentially new strategy to aid in overcoming or minimizing this problem is enhancement of pathogen sensitivity to fungicides, or "chemosensitization." Chemosensitization can be accomplished by combining a commercial fungicide with a certain non- or marginally fungicidal substance at levels where, alone, neither compound would be effective. Chemosensitization decreases the probability of the pathogen developing resistance, reduces the toxic impact on the environment by lowering effective dosage levels of toxic fungicides, and improves efficacy of antifungal agents. The present study shows that the antifungal activity of azole and strobilurin fungicides can be significantly enhanced through their co-application with certain natural or synthetic products against several economically important plant pathogenic fungi. Quadris (azoxystrobin) combined with thymol at a non-fungitoxic concentration produced much higher growth inhibition of Bipolaris sorokiniana, Phoma glomerata, Alternaria sp. and Stagonospora nodorum than the fungicide alone. The effect of Dividend (difenoconazole) applied with thymol significantly enhanced antifungal activity against B. sorokiniana and S. nodorum. Folicur (tebuconazole) combined with 4-hydroxybenzaldehyde (4-HBA), 2,3-dihydroxybenzaldehyde or thymol significantly inhibited growth of Alternaria alternata, at a much greater level than the fungicide alone. In addition, co-application of Folicur and 4-HBA resulted in a similar enhancement of antifungal activity against Fusarium culmorum. Lastly, we discovered that metabolites in the culture liquid of Fusarium sambucinum biocontrol isolate FS-94 also had chemosensitizing activity, increasing S. nodorum sensitivity to Folicur and Dividend.

  5. Spectrophotometric determination of the fungicide captan.

    Science.gov (United States)

    Galeano, Teresa; Guiberteau, Agustina; Mora, Nielene M; Alvarez, Pedro R; Salinas, Francisco

    2002-11-01

    A spectrophotometric method for the determination of the fungicide captan has been developed based on its reaction with thiosemicarbazide. The absorbance was measured at 315 nm. The effects of the proportion of water, thiosemicarbazide concentration, pH and temperature on this reaction was studied to select the best chemical conditions. The calibration graph was obtained between 1.2 and 30 ppm and the detection limit is 0.5 ppm. The RSD (n = 10) was 1.34%. Possible interference of various pesticides was examined. The method was applied to the determination of captan in agrochemical formulations. Results agree well with the labelled values and also with results that were obtained by a polarographic method.

  6. Environmental fungicides and triazole resistance in Aspergillus.

    Science.gov (United States)

    Bowyer, Paul; Denning, David W

    2014-02-01

    Fungal diseases are problematic in both human health and agriculture. Treatment options are limited and resistance may emerge. The relatively recent recognition of triazole resistance in Aspergillus fumigatus has prompted questioning of the origin of resistance. While multiple mechanisms are described in clinical isolates from triazole-treated patients, some de novo resistance is also recognised, especially attributable to TR34 /L98H. Such strains probably arose in the environment, and, indeed, multiple studies have now demonstrated TR(34) /L98H triazole resistance strains of A. fumigatus from soil. Docking and other in vitro studies are consistent with environmental resistance induction through exposure to certain triazole fungicides, notably difenoconazole, propiconazole, epoxiconazole, bromuconazole and tebuconazole. This article addresses the potential implications of this issue for both human health and food security.

  7. KETAHANAN JAMUR TERHADAP FUNGISIDA DI INDONESIA (RESISTANCE OF FUNGI AGAINST FUNGICIDES IN INDONESIA)

    OpenAIRE

    Sumardiyono, Christanti

    2016-01-01

    Plant diseases control with fungicides had been practised for decades in Indonesia. The orientation of consumers to have high quality agriculture product caused the intensif use of pesticides including fungicides. Systemic fungicides were used as therapeutant agens for disease control. Intensively used and sublethal dose of systemic fungicides induced fungi to be resistant. The purpose of this article was to describe the occurrence of developing fungicides resistance strains. Several publicat...

  8. Synthesis and fungicidal activity of a series of novel aryloxylepidines.

    Science.gov (United States)

    Kirby, N V; Daeuble, J F; Davis, L N; Hannum, A C; Hellwig, K; Lawler, L K; Parker, M H; Pieczko, M E

    2001-09-01

    A series of novel (hetero) aryloxylepidine derivatives was devised as hybrid structures of the phenoxyquinoline and phenethoxyquin(az)oline fungicides. Synthesis of these targets required the development of several new routes to derivatised 4-hydroxymethylquinolines, and subsequent coupling with phenols or haloarenes. The aryloxylepidines generally showed moderate broad-spectrum fungicidal activity across several diseases of cereals. Substitution of the quinoline ring with chlorine at the 7- and/or 5-positions gave molecules with high levels of protectant activity against Erysiphe graminis f sp tritici (powdery mildew of wheat), but this did not improve the level of fungicidal activity against other diseases. In vitro activity against mitochondrial electron transport complex I (MET) derived from Ustilago maydis showed that 8-fluorolepidine analogues were moderately active at this target site, while the more fungicidally active 7- and 5,7-substituted compounds were inactive. This indicates that MET is not the primary target of these highly active powdery mildewicides.

  9. 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.

  10. 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...

  11. Sensitivity of Botrytis cinerea Isolates Against Some Fungicides ...

    African Journals Online (AJOL)

    Desen

    2012-01-26

    Jan 26, 2012 ... concentrations, in controlling gray mold in fruit infection. In addition, fitness of ... the fungicide resistance problem within this region would ... sterile long and narrow wood strips in sterile plastic boxes contain- ing wetted ...

  12. 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...

  13. 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...

  14. Fungicide effects on fungal community composition in the wheat phyllosphere.

    Science.gov (United States)

    Karlsson, Ida; Friberg, Hanna; Steinberg, Christian; Persson, Paula

    2014-01-01

    The fungicides used to control diseases in cereal production can have adverse effects on non-target fungi, with possible consequences for plant health and productivity. This study examined fungicide effects on fungal communities on winter wheat leaves in two areas of Sweden. High-throughput 454 sequencing of the fungal ITS2 region yielded 235 operational taxonomic units (OTUs) at the species level from the 18 fields studied. It was found that commonly used fungicides had moderate but significant effect on fungal community composition in the wheat phyllosphere. The relative abundance of several saprotrophs was altered by fungicide use, while the effect on common wheat pathogens was mixed. The fungal community on wheat leaves consisted mainly of basidiomycete yeasts, saprotrophic ascomycetes and plant pathogens. A core set of six fungal OTUs representing saprotrophic species was identified. These were present across all fields, although overall the difference in OTU richness was large between the two areas studied.

  15. Current possibilities and prospects of using fungicides in forestry

    Directory of Open Access Journals (Sweden)

    Okorski Adam

    2015-06-01

    Full Text Available The possibility of using chemicals in European forestry is extremely limited due to the binding legal regulations and specific conditions concerning the market of plant protection products. This is reflected in the limited availability of active fungicides in forestry. Due to this limitation, practitioners using fungicides in forest nurseries and forest cultivation must have substantial knowledge of the biology of pathogens to ensure satisfactorily effective protection.

  16. FUNGICIDE APPLICATION FOR MAINTAINING POSTHARVEST QUALITY IN TOMATO FRUITS

    OpenAIRE

    D. M. Vani; S. M. Bonaldo

    2014-01-01

    Tomato fruits are usually consumed soon after harvest, however, as they are mainly comprised of water, and its walls are fragile, facilitates the emergence of diseases, making necessary the use of preventive measures in the field in order to reduce incidence of disease. The objective is then to evaluate the effect of foliar application of fungicides on the final quality of tomato fruits in postharvest. There were 13 applications of foliar fungicides Azoxystrobin+Cyproconazol and Boscalida, 7 ...

  17. Triazole fungicide tebuconazole disrupts human placental trophoblast cell functions.

    Science.gov (United States)

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

    2016-05-05

    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.

  18. 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

    2015-06-01

    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.

  19. Morphogenetic Alterations of Alternaria alternata Exposed to Dicarboximide Fungicide, Iprodione

    Science.gov (United States)

    Kim, Eunji; Lee, Hye Min; Kim, Young Ho

    2017-01-01

    Fungicide-resistant Alternaria alternata impede the practical control of the Alternaria diseases in crop fields. This study aimed to investigate cytological fungicide resistance mechanisms of A. alternata against dicarboximide fungicide iprodione. A. alternata isolated from cactus brown spot was cultured on potato-dextrose agar (PDA) with or without iprodione, and the fungal cultures with different growth characteristics from no, initial and full growth were observed by light and electron microscopy. Mycelia began to grow from one day after incubation (DAI) and continued to be in full growth (control-growth, Con-G) on PDA without fungicide, while on PDA with iprodione, no fungal growth (iprodione-no growth, Ipr-N) occurred for the first 3 DAI, but once the initial growth (iprodione-initial growth, Ipr-I) began at 4–5 DAI, the colonies grew and expanded continuously to be in full growth (iprodione-growth, Ipr-G), suggesting Ipr-I may be a turning moment of the morphogenetic changes resisting fungicidal toxicity. Con-G formed multicellular conidia with cell walls and septa and intact dense cytoplasm. In Ipr-N, fungal sporulation was inhibited by forming mostly undeveloped unicellular conidia with degraded and necrotic cytoplasm. However, in Ipr-I, conspicuous cellular changes occurred during sporulation by forming multicellular conidia with double layered (thickened) cell walls and accumulation of proliferated lipid bodies in the conidial cytoplasm, which may inhibit the penetration of the fungicide into conidial cells, reducing fungicide-associated toxicity, and may be utilized as energy and nutritional sources, respectively, for the further fungal growth to form mature colonies as in Ipr-G that formed multicellular conidia with cell walls and intact cytoplasm with lipid bodies as in Con-G. PMID:28167893

  20. 40 CFR 180.554 - Kresoxim-methyl; tolerances for residues.

    Science.gov (United States)

    2010-07-01

    ... metabolites as follows: (E)-2- -phenyl-2-(methoxyimido)acetic acid; (E)-2- -phenyl-2-(methoxyimido)acetic acid (free and glucose conjugated); and (E)-2- phenyl-2-(methoxyimido)acetic acid (free and glucose...- -phenyl-2-(methoxyimido)acetic acid resulting from the use of the fungicide kresoxim-methyl:...

  1. Synthesis and bioactivity of novel coumarin derivatives containing (E)-methyl 2-(methoxyimino)-2-phenylacetates

    Institute of Scientific and Technical Information of China (English)

    Ai Ying Guan; Chang Ling Liu; Zhi Nian Li; Ming Xing Zhang

    2011-01-01

    Ten coumarin derivatives containing (E)-methyl 2-(methoxyimino)-2-phenylacetate were synthesized and bioassayed. The compounds were identified by IR, 1H NMR and elemental analyses. The test results indicated that compound 5j (R1 is methyl and R2 is n-C6H13) was the optimal structure in this paper with good fungicidal activity against CDM (85%) at 6.25 mg/L concentration.

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

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup

    2015-01-01

    Abstract:A long tradition for using reduced fungicides rates in cereals have been exploited successfully in Denmark for more than 20 years and a similar trend has also been seen in other Northern European countries. The use of reduced and appropriate dose rates have been driven by field trials wi...... that reduced fungicide rates select less for fungicide resistance and can help to delay development of resistance.......Abstract:A long tradition for using reduced fungicides rates in cereals have been exploited successfully in Denmark for more than 20 years and a similar trend has also been seen in other Northern European countries. The use of reduced and appropriate dose rates have been driven by field trials...... to be controlled successfully at rates down to quarter rates. Fungicides, in general, show highly variable dose responses for specific diseases, which is important to know when specific advice is given. Preventive treatments generally require less input compared with treatments during the latent period or later...

  3. Efficacy of conventional fungicides in controlling tomato grey mold

    Directory of Open Access Journals (Sweden)

    A. Mavandadi

    2016-02-01

    Full Text Available One of the important diseases of tomato plants is grey mold, which is caused by Botrytis cinerea. In this research, the effects of 10 fungicides on mycelial growth and conidia germination of B. cinerea were investigated. Results showed that carbendazim with a median inhibitory concentration (IC50 value of 0.1 mg/L had the highest inhibitory effect and bordeaux mixture with an IC50 value of 1096.9 mg/L had the lowest inhibitory effect. Benomyl with an IC50 value of 0.04 mg/L had the most visual effects, after 3 and 7 days, on mycelial growth of B. cinerea. The effect of fungicides on preventing fruit wound development caused by B. cinerea was investigated, too. In benomyl treatment, wound diameter on the fruits was 0.73 mm and in copper oxychloride treatment was 6.16 mm, showing the highest and the lowest effective fungicides in the prevention of wound expansion. Different strains of the fungus were collected from various areas in Isfahan province and the effect of the fungicides on their conidial germination was evaluated. Results revealed that the collected isolates had different susceptibility to the 10 tested fungicides.

  4. Impact of fungal drug transporters on fungicide sensitivity, multidrug resistance and virulence

    NARCIS (Netherlands)

    Waard, de M.A.; Andrade, A.C.; Hayashi, K.; Schoonbeek, H.; Stergiopoulos, I.; Zwiers, L.H.

    2006-01-01

    Drug transporters are membrane proteins that provide protection for organisms against natural toxic products and fungicides. In plant pathogens, drug transporters function in baseline sensitivity to fungicides, multidrug resistance (MDR) and virulence on host plants. This paper describes drug transp

  5. Synthesis and fungicidal activity of some alkyl – 2,4 ...

    African Journals Online (AJOL)

    In vitro fungicidal assay of these alkyl sulfenate esters against Aspergillus flavus, Rhizopus stolonifer ... Increase in chain length of the alkyl substituents was found to reduce the fungicidal activity of the alkyl sulfenate esters. ... Article Metrics.

  6. 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 eac...... as endocrine disruptors in vivo, although the profile of action in vivo varies. As ketoconazole is known to implicate numerous endocrine-disrupting effects in humans, the concern for the effects of the other tested azole fungicides in humans is growing.......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...

  7. Combretastatin A-4 and Derivatives: Potential Fungicides Targeting Fungal Tubulin.

    Science.gov (United States)

    Ma, Zhong-lin; Yan, Xiao-jing; Zhao, Lei; Zhou, Jiu-jiu; Pang, Wan; Kai, Zhen-peng; Wu, Fan-hong

    2016-02-01

    Combretastatin A-4, first isolated from the African willow tree Combretum caffrum, is a tubulin polymerization inhibitor in medicine. It was first postulated as a potential fungicide targeting fungal tubulin for plant disease control in this study. Combretastatin A-4 and its derivatives were synthesized and tested against Rhizoctonia solani and Pyricularia oryzae. Several compounds have EC50 values similar to or better than that of isoprothiolane, which is widely used for rice disease control. Structure-activity relationship study indicated the the cis configuration and hydroxyl group in combretastatin A-4 are crucial to the antifungal effect. Molecular modeling indicated the binding sites of combretastatin A-4 and carbendazim on fungal tubulin are totally different. The bioactivity of combretastatin A-4 and its derivatives against carbendazim-resistant strains was demonstrated in this study. The results provide a new approach for fungicide discovery and fungicide resistance management.

  8. Baseline sensitivity of Brazilian Mycosphaerella fijiensis isolates to protectant and systemic fungicides.

    OpenAIRE

    GOMES, L. I. S.; BIBIANO, L. B. J.; SILVA, G.F. da.; HANADA, R.E.; MIZUBUTI, E. S. G.

    2015-01-01

    Black Sigatoka caused by Mycosphaerella fijiensis is a foliar disease that affects banana plants and large amounts of fungicides are required to prevent crop losses. Intensive applications of single-site fungicides can select for fungicide-resistant isolates. The objective of this study was to assess the sensitivity of 60 isolates of M. fijiensis to commonly used fungicides. Using two different protocols, microtiter and Petri plate tests, the effective concentration at which mycelium growth i...

  9. Acaricide, fungicide and drug interactions in honey bees (Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Reed M Johnson

    Full Text Available BACKGROUND: Chemical analysis shows that honey bees (Apis mellifera and hive products contain many pesticides derived from various sources. The most abundant pesticides are acaricides applied by beekeepers to control Varroa destructor. Beekeepers also apply antimicrobial drugs to control bacterial and microsporidial diseases. Fungicides may enter the hive when applied to nearby flowering crops. Acaricides, antimicrobial drugs and fungicides are not highly toxic to bees alone, but in combination there is potential for heightened toxicity due to interactive effects. METHODOLOGY/PRINCIPAL FINDINGS: Laboratory bioassays based on mortality rates in adult worker bees demonstrated interactive effects among acaricides, as well as between acaricides and antimicrobial drugs and between acaricides and fungicides. Toxicity of the acaricide tau-fluvalinate increased in combination with other acaricides and most other compounds tested (15 of 17 while amitraz toxicity was mostly unchanged (1 of 15. The sterol biosynthesis inhibiting (SBI fungicide prochloraz elevated the toxicity of the acaricides tau-fluvalinate, coumaphos and fenpyroximate, likely through inhibition of detoxicative cytochrome P450 monooxygenase activity. Four other SBI fungicides increased the toxicity of tau-fluvalinate in a dose-dependent manner, although possible evidence of P450 induction was observed at the lowest fungicide doses. Non-transitive interactions between some acaricides were observed. Sublethal amitraz pre-treatment increased the toxicity of the three P450-detoxified acaricides, but amitraz toxicity was not changed by sublethal treatment with the same three acaricides. A two-fold change in the toxicity of tau-fluvalinate was observed between years, suggesting a possible change in the genetic composition of the bees tested. CONCLUSIONS/SIGNIFICANCE: Interactions with acaricides in honey bees are similar to drug interactions in other animals in that P450-mediated detoxication

  10. Acaricide, fungicide and drug interactions in honey bees (Apis mellifera).

    Science.gov (United States)

    Johnson, Reed M; Dahlgren, Lizette; Siegfried, Blair D; Ellis, Marion D

    2013-01-01

    Chemical analysis shows that honey bees (Apis mellifera) and hive products contain many pesticides derived from various sources. The most abundant pesticides are acaricides applied by beekeepers to control Varroa destructor. Beekeepers also apply antimicrobial drugs to control bacterial and microsporidial diseases. Fungicides may enter the hive when applied to nearby flowering crops. Acaricides, antimicrobial drugs and fungicides are not highly toxic to bees alone, but in combination there is potential for heightened toxicity due to interactive effects. Laboratory bioassays based on mortality rates in adult worker bees demonstrated interactive effects among acaricides, as well as between acaricides and antimicrobial drugs and between acaricides and fungicides. Toxicity of the acaricide tau-fluvalinate increased in combination with other acaricides and most other compounds tested (15 of 17) while amitraz toxicity was mostly unchanged (1 of 15). The sterol biosynthesis inhibiting (SBI) fungicide prochloraz elevated the toxicity of the acaricides tau-fluvalinate, coumaphos and fenpyroximate, likely through inhibition of detoxicative cytochrome P450 monooxygenase activity. Four other SBI fungicides increased the toxicity of tau-fluvalinate in a dose-dependent manner, although possible evidence of P450 induction was observed at the lowest fungicide doses. Non-transitive interactions between some acaricides were observed. Sublethal amitraz pre-treatment increased the toxicity of the three P450-detoxified acaricides, but amitraz toxicity was not changed by sublethal treatment with the same three acaricides. A two-fold change in the toxicity of tau-fluvalinate was observed between years, suggesting a possible change in the genetic composition of the bees tested. Interactions with acaricides in honey bees are similar to drug interactions in other animals in that P450-mediated detoxication appears to play an important role. Evidence of non-transivity, year-to-year variation

  11. 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.

  12. 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 criteria. A disa

  13. An examination of fungicide sensitivity of Cercospora beticola in Michigan and Ontario sugarbeet (Beta vulgaris) (2014)

    Science.gov (United States)

    Leaf spot caused by Cercospora beticola Sacc. is the major foliar disease of sugarbeet in Michigan. Fungicide applications are one of the most important tools in managing this disease. However, fungicide resistance has developed in C. beticola to several classes of fungicides. To look for the levels...

  14. DNA Methylation

    OpenAIRE

    Alokail, Majed S.; Alenad, Amal M.

    2015-01-01

    The DNA of E. coli contains 19,120 6-methyladenines and 12,045 5-methylcytosines in addition to the four regular bases and these are formed by the postreplicative action of three DNA methyltransferases. The majority of the methylated bases are formed by the Dam and Dcm methyltransferases encoded by the dam (DNA adenine methyltransferase) and dcm (DNA cytosine methyltransferase) genes. Although not essential, Dam methylation is important for strand discrimination during repair of replication e...

  15. In vitro metabolism and interactions of the fungicide metalaxyl in human liver preparations.

    Science.gov (United States)

    Abass, Khaled; Reponen, Petri; Jalonen, Jorma; Pelkonen, Olavi

    2007-01-01

    In order to provide additional information for risk assessment of the fungicide metalaxyl, the main objectives were (1) to elucidate the interactions of metalaxyl with different human liver cytochrome P450 enzymes, (2) to tentitatively identify and (semi)quantify metabolites in vitro and (3) to identify human CYP enzymes responsible for metabolism. The mean inhibitory concentrations (IC(50)) for 7-pentoxyresorufin-O-dealkylation (CYP2B) and bupropion hydroxylation (2B6) were 48.9 and 41.7μM, respectively. The biotransformation reactions were hydroxylation, (di)demethylation and lactone formation. In human liver microsomes predominant metabolites were two hydroxymetalaxyl derivatives or atropisomers of one of the derivatives. On the basis of previous rat studies these could be N-(2-hydroxymethyl-6-methylphenyl)-N-(methoxyacetyl)alanine methyl ester and/or N-(2,6-dimethyl-5-hydroxyphenyl)-N-(methoxyacetyl)alanine methyl ester. The amounts of didemethylmetalaxyl N-(2,6-dimethylphenyl)-N-(hydroxyacetyl)alanine and lactone 4-(2,6-dimethylphenyl)-3-methylmorpholine-2,5-dione were higher in homogenates than microsomes. The carcinogenic 2,6-dimethylaniline was not detected. Among the nine major human CYPs, CYP3A4 was the only one responsible for metalaxyl hydroxylation, while CYP2B6 was the major isoform responsible for (di)demethylation and lactone formation. Copyright © 2006 Elsevier B.V. All rights reserved.

  16. Efficiency of Several Fungicides to Control Wheat Powdery Mildew%几种杀菌剂对小麦白粉病的防治效果

    Institute of Scientific and Technical Information of China (English)

    杨共强; 宋玉立; 何文兰; 孙静

    2011-01-01

    为了筛选对小麦白粉病有效的防治药剂,在小麦白粉病发病初期,选用7.5%氟环唑乳油、50%醚菌酯干悬浮剂等13种杀菌剂进行喷雾,25d后调查发病情况.结果表明,13种杀菌剂对小麦白粉病均有一定的防效,为40.5%~86.8%.其中50%醚菌酯干悬浮剂、7.5%氟环唑乳油、25%丙环唑乳油3种药剂对小麦白粉病的防效最好,分别为86.8%、85.1%、79.3%其次为50%禾瑞水分散粒剂、5%烯肟菌胺乳油、12.5%烯唑醇可湿性粉剂、15%氯啶菌酯乳油、20%戊唑醇·烯肟菌胺悬浮剂和15%三唑酮可湿性粉剂6种药剂,防效在60.8%~69.3%.以上9种药剂对小麦白粉病有较好的防治效果,可在生产上推广应用.%In order to screen effective fungicides to control wheat powdery mildew, the efficacy of 13 fungicides was measured against wheat powdery mildew in the fields. The fungicides were spayed at the early stage of the disease and the disease condition was investigated after 25 days. The results showed that 13 fungicides had some control effects of 40. 5%-86. 8%. Three fungicides, 50% Kresoxim-methyl DF,7. 5% Epoxiconazole EC and 25% Propiconazole EC had best control effect (86. 8%, 85. 1% and 79. 3%, respectively), and the other six fungicides, 50% Cyprodinil WG, 5% SYP-1620 EC,12. 5% Diniconazole WP,15% SYP-7017 EC, 20% Tebuconazole ~ SYP-1620 SC and 15% Triadimefon WP also had good control effect (69. 3%, 66. 7%, 65.0%, 63. 6%, 62. 4% and 60. 8% .respectively). The nine fungicides were recommended for use in wheat production.

  17. 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 M.; 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

  18. Fungicides for organic cantaloupe production in Oklahoma: An initial assessment

    Science.gov (United States)

    Fungicides that are potentially useful in organic production were evaluated for foliar disease control in cantaloupe (Cucumis melo L. var. reticulates ’Israeli’) during 2009 at Lane, Oklahoma. Milstop (85% potassium bicarbonate), Neem oil, Bonide liquid copper (10% copper octanoate), Serenade (QST ...

  19. Governing principles can guide fungicide-resistance management tactics.

    Science.gov (United States)

    van den Bosch, Frank; Oliver, Richard; van den Berg, Femke; Paveley, Neil

    2014-01-01

    Fungicide-resistance management would be more effective if principles governing the selection of resistant strains could be determined and validated. Such principles could then be used to predict whether a proposed change to a fungicide application program would decrease selection for resistant strains. In this review, we assess a governing principle that appears to have good predictive power. The principle states that reducing the product of the selection coefficient (defined as the difference between the per capita rate of increase of the sensitive and resistant strains) and the exposure time of the pathogen to the fungicide reduces the selection for resistance. We show that observations as well as modeling studies agree with the predicted effect (i.e., that a specific change to a fungicide program increased or decreased selection or was broadly neutral in its effect on selection) in 84% of the cases and that only 5% of the experimental results contradict predictions. We argue that the selection coefficient and exposure time principle can guide the development of resistance management tactics.

  20. Analysis of the mutations inducedd by conazole fungicides in vivo

    Science.gov (United States)

    The mouse liver tumorigenic conazo1e fungicides triadimefon and propiconazo1e have previously been shown to be in vivo mouse liver mutagens in the Big Blue" transgenic mutation assay when administered in feed at tumorigenic doses, whereas the nontumorigenic conazo1e myc1obutani1 ...

  1. Efficacy of fungicides against Phytophthora cactorum on Viola.

    Science.gov (United States)

    Blindeman, L; Heungens, K; Goossens, F; Gobin, B

    2009-01-01

    Phytophthora cactorum caused significant losses to pansies during the heat wave at the end of the summer of 2006. Infected plants showed foliage that appeared stunted and chlorotic, with wilting occurring even when soil moisture was adequate. When uprooted, symptomatic plants typically possess a surprisingly healthy looking and well-developed root system, but stem and root tissue at the soil interface is discoloured (purple to dark brown) and soft. Older Leaves turn yellow and when the stem base is attacked, the plant dies. Phytophthora cactorum was identified from stem and root tissue with both morphological and molecular techniques. To evaluate the efficacy of different fungicides against this pathogen, healthy plants were infected with zoospores of a Phytophthora cactorum isolate collected from commercial plants. Eleven fungicides were evaluated and compared to an untreated control. Two fungicides were applied via root drenching, 7 days before inoculation with zoospores of P. cactorum. The other fungicides were applied by spraying 24 hours after inoculation with P. cactorum. Preventive drenching with the combined formulation of fenamidone + fosethyl offered the best protection against P. cactorum, while drenching with dimethomorf also resulted in an obvious reduction in the number of infected plants. Foliar application was less successful, as only a combined formulation of mancozeb + metalaxyl-M gave sufficient protection. In conclusion, preventive drenching appears to be the best solution to prevent infection with P. cactorum, especially during warm weather periods, which are conducive to pathogen and disease development.

  2. Comparison of three fungicide spray advisories for lettuce downy mildew

    NARCIS (Netherlands)

    Wu, B.M.; Subbarao, K.V.; Bruggen, van A.H.C.; Koike, S.T.

    2001-01-01

    Lettuce growers in coastal California have relied mainly on protective fungicide sprays to control downy mildew. Thus, timing of sprays before infection is critical for optimal results. A leaf-wetness-driven, infection-based advisory system, previously developed, did not always perform satisfactoril

  3. Molecular basis of fungicide resistance in Cercospora beticola

    Science.gov (United States)

    Cercospora leaf spot (CLS), caused by the fungus Cercospora beticola, is the most important foliar disease of sugarbeet. Control measures include the application of sterol demethylation inhibitor (DMI) and quinone outside inhibitor (QoI) fungicides. Understanding the molecular mechanism of fungici...

  4. [Use of cytochemical methods for diagnosis in fungicide research].

    Science.gov (United States)

    Müller, H M; Casperson, G

    1984-01-01

    Cytochemical localization of acid and alkaline phosphatases, cytochrom c-oxidase, peroxidases and catalase was carried out on Phytophthora infestans (Mont.) de By. and Mucor mucedo (L.) Fres. First results are obtained about the influence of sublethal dosages of fungicidal compounds on the demonstration of these enzymes in the electron-microscope.

  5. The toxicity of the fungicide Propiconazole to soil flagellates

    DEFF Research Database (Denmark)

    Ekelund, Flemming; Westergaard, Kamma; Søe, Dorthe

    2000-01-01

    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...

  6. The pH Value of Fungicide, Insecticide and Mineral Fertilizer Mixtures Depending on Water Quality

    Directory of Open Access Journals (Sweden)

    Dušanka Inđić

    2008-01-01

    Full Text Available The paper deals with the effect of water quality on the pH value of fungicides, insecticides, mineral fertilizers and their mixtures. The fungicides propineb (Antracol WP-70 and mancozeb (Dithane M-70, insecticides pirimiphos-methyl (Actellic-50 and imidacloprid(Confidor 200-SL, several fertilizers (Ferticare I, Ferticare II, Ferticare III and Wuxal Super and their mixtures were analyzed for pH value under laboratory conditions using a potentiometric pH meter. Measurements were made directly after preparation or mixing with tap and well water and 24 hours later. Tap water exhibited a neutral reaction. A slightly alkaline reaction of well water was mostlikely due to high ammonium content. The suspensions of Antracol WP-70 exhibited slightly alkaline reactions with both water types during 24 hours. The spray liquids of Dithane M-70 mixed with tap or well water had neutral reaction after preparation and slightly alkaline reaction after 24 hours. The emulsions of Actellic-50 showed neutral reaction with both water types, followed by a pH increase in tap water after 24 hours. The solutions of Confidor200-SL had a slightly alkaline reaction after mixing and the pH value increased with both water types after 24 hours. It is therefore recommended to apply these insecticides directly after preparation. Mineral fertilizers considerably reduced pH values of the fungicide and insecticide components in double and triple mixtures, especially Ferticare nutrients which had a moderately acid reaction. Wuxal Super had a neutral reaction with both water types.The mixtures with well water increased pH values, which indicates that water pH does affect the pH value of the mixture. Both individual fertilizers and all mixtures (double and triple with Ferticare had pH values between 2.4 and 6, which allows their active liquids to be stored for 12 to 24 hours. The suspensions (Antracol WP-70, double and triple mixtures, emulsions (Actellic-50 and Actellic-50+Wuxal Super

  7. Does nutrient enrichment compensate fungicide effects on litter decomposition and decomposer communities in streams?

    Science.gov (United States)

    Fernández, Diego; Tummala, Mallikarjun; Schreiner, Verena C; Duarte, Sofia; Pascoal, Cláudia; Winkelmann, Carola; Mewes, Daniela; Muñoz, Katherine; Schäfer, Ralf B

    2016-05-01

    Nutrient and pesticide pollution are widespread agricultural stressors. Fungicides may affect freshwater fungi, which play an important role in litter decomposition (LD), whereas moderate nutrient enrichment can stimulate LD. We examined potential interaction effects of nutrients and fungicides on decomposer communities and LD in a 14-day two-factorial (fungicide and nutrient treatments) mesocosm experiment. Fungicide exposure was limited to 4days to simulate episodic contamination. Only the microbial community responded significantly to the experimental factors, though non-significant increases >20% were found for invertebrate decomposer weight gain and LD under high-nutrient conditions. Fungal community structure responded more strongly to fungicides than sporulation. Sporulation responded strongest to nutrients. Bacterial community structure was affected by both factors, although only nutrients influenced bacterial density. Our results suggest effects from fungicides at field-relevant levels on the microbial community. Whether these changes propagate to invertebrate communities and LD remains unclear and should be analysed under longer and recurrent fungicide exposure.

  8. Combination Effects of (TriAzole Fungicides on Hormone Production and Xenobiotic Metabolism in a Human Placental Cell Line

    Directory of Open Access Journals (Sweden)

    Svenja Rieke

    2014-09-01

    Full Text Available Consumers are exposed to multiple residues of different pesticides via the diet. Therefore, EU legislation for pesticides requires the evaluation of single active substances as well as the consideration of combination effects. Hence the analysis of combined effects of substances in a broad dose range represents a key challenge to current experimental and regulatory toxicology. Here we report evidence for additive effects for (triazole fungicides, a widely used group of antifungal agents, in the human placental cell line Jeg-3. In addition to the triazoles cyproconazole, epoxiconazole, flusilazole and tebuconazole and the azole fungicide prochloraz also pesticides from other chemical classes assumed to act via different modes of action (i.e., the organophosphate chlorpyrifos and the triazinylsulfonylurea herbicide triflusulfuron-methyl were investigated. Endpoints analysed include synthesis of steroid hormone production (progesterone and estradiol and gene expression of steroidogenic and non-steroidogenic cytochrome-P-450 (CYP enzymes. For the triazoles and prochloraz, a dose dependent inhibition of progesterone production was observed and additive effects could be confirmed for several combinations of these substances in vitro. The non-triazoles chlorpyrifos and triflusulfuron-methyl did not affect this endpoint and, in line with this finding, no additivity was observed when these substances were applied in mixtures with prochloraz. While prochloraz slightly increased aromatase expression and estradiol production and triflusulfuron-methyl decreased estradiol production, none of the other substances had effects on the expression levels of steroidogenic CYP-enzymes in Jeg-3 cells. For some triazoles, prochloraz and chlorpyrifos a significant induction of CYP1A1 mRNA expression and potential combination effects for this endpoint were observed. Inhibition of CYP1A1 mRNA induction by the AhR inhibitor CH223191 indicated AhR receptor dependence this

  9. Combination Effects of (Tri)Azole Fungicides on Hormone Production and Xenobiotic Metabolism in a Human Placental Cell Line

    Science.gov (United States)

    Rieke, Svenja; Koehn, Sophie; Hirsch-Ernst, Karen; Pfeil, Rudolf; Kneuer, Carsten; Marx-Stoelting, Philip

    2014-01-01

    Consumers are exposed to multiple residues of different pesticides via the diet. Therefore, EU legislation for pesticides requires the evaluation of single active substances as well as the consideration of combination effects. Hence the analysis of combined effects of substances in a broad dose range represents a key challenge to current experimental and regulatory toxicology. Here we report evidence for additive effects for (tri)azole fungicides, a widely used group of antifungal agents, in the human placental cell line Jeg-3. In addition to the triazoles cyproconazole, epoxiconazole, flusilazole and tebuconazole and the azole fungicide prochloraz also pesticides from other chemical classes assumed to act via different modes of action (i.e., the organophosphate chlorpyrifos and the triazinylsulfonylurea herbicide triflusulfuron-methyl) were investigated. Endpoints analysed include synthesis of steroid hormone production (progesterone and estradiol) and gene expression of steroidogenic and non-steroidogenic cytochrome-P-450 (CYP) enzymes. For the triazoles and prochloraz, a dose dependent inhibition of progesterone production was observed and additive effects could be confirmed for several combinations of these substances in vitro. The non-triazoles chlorpyrifos and triflusulfuron-methyl did not affect this endpoint and, in line with this finding, no additivity was observed when these substances were applied in mixtures with prochloraz. While prochloraz slightly increased aromatase expression and estradiol production and triflusulfuron-methyl decreased estradiol production, none of the other substances had effects on the expression levels of steroidogenic CYP-enzymes in Jeg-3 cells. For some triazoles, prochloraz and chlorpyrifos a significant induction of CYP1A1 mRNA expression and potential combination effects for this endpoint were observed. Inhibition of CYP1A1 mRNA induction by the AhR inhibitor CH223191 indicated AhR receptor dependence of this effect. PMID

  10. DNA methylation

    DEFF Research Database (Denmark)

    Williams, Kristine; Christensen, Jesper; Helin, Kristian

    2012-01-01

    DNA methylation is involved in key cellular processes, including X-chromosome inactivation, imprinting and transcriptional silencing of specific genes and repetitive elements. DNA methylation patterns are frequently perturbed in human diseases such as imprinting disorders and cancer. The recent...... discovery that the three members of the TET protein family can convert 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC) has provided a potential mechanism leading to DNA demethylation. Moreover, the demonstration that TET2 is frequently mutated in haematopoietic tumours suggests that the TET...... proteins are important regulators of cellular identity. Here, we review the current knowledge regarding the function of the TET proteins, and discuss various mechanisms by which they contribute to transcriptional control. We propose that the TET proteins have an important role in regulating DNA methylation...

  11. 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.

  12. Fungicidal activity of silver nanoparticles against Alternaria brassicicola

    Science.gov (United States)

    Gupta, Deepika; Chauhan, Pratima

    2016-04-01

    This work highlighted the fungicidal properties of silver nanoparticles against Alternaria brassicicola. Alternaria brassicicola causes Black spot of Cauliflower, radish, cabbage, kale which results in sever agricultural loss. We treat the synthesised silver nanoparticles (AgNPs) of 10, 25, 50, 100 and 110 ppm concentrations against Alternaria brassicicola on PDA containing Petri dish. We calculated inhibitory rate (%) in order to evaluate the antifungal efficacy of silver nanoparticles against pathogens. Treatment with 100ppm AgNPs resulted in maximum inhibition of Alternaria brassicicola i.e.92.2%. 110ppm of AgNPS also shows the same result, therefore 100ppm AgNPs was treated as optimize concentration. AgNPs effectively inhibited the growth of a Alternaria brassicicola, which suggests that AgNPs could be used as fungicide in plant disease management. Further research and development are necessary to translate this technology into plant disease management strategies.

  13. Determination of strobilurin fungicides in cotton seed by combination of acetonitrile extraction and dispersive liquid-liquid microextraction coupled with gas chromatography.

    Science.gov (United States)

    Xue, Jiaying; Li, Huichen; Liu, Fengmao; Jiang, Wenqing; Chen, Xiaochu

    2014-04-01

    The simultaneous determination of four strobilurin fungicides (picoxystrobin, kresoxim-methyl, trifloxystrobin, and azoxystrobin) in cotton seed by combining acetonitrile extraction and dispersive liquid-liquid microextraction was developed prior to GC with electron capture detection. Several factors, including the type and volume of the extraction and dispersive solvents, extraction condition and time, and salt addition, were optimized. The analytes were extracted with acetonitrile from cotton seed and the clean-up was carried out by primary secondary amine. Afterwards, 60 μL of n-hexane/toluene (1:1, v/v) with a lower density than water was mixed with 1 mL of the acetonitrile extract, then the mixture was injected into 7 mL of distilled water. A 0.1 mL pipette was used to collect a few microliters of n-hexane/toluene from the top of the aqueous solution. The enrichment factors of the analytes ranged from 36 to 67. The LODs were in the range of 0.1 × 10(-3) -2 × 10(-3) mg/kg. The relative recoveries varied from 87.7 to 95.2% with RSDs of 4.1-8.5% for the four fungicides. The good performance of the method, compared with the conventional pretreatments, has demonstrated it is suitable for determining low concentrations of strobilurin fungicide residues in cotton seed.

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

    Science.gov (United States)

    2013-01-01

    Insecticidal, repellent and fungicidal properties of novel trifluoromethylphenyl amidesq Maia Tsikolia a,⇑, Ulrich R. Bernier a, Monique R. Coy a...Swale e, Jeffrey R. Bloomquist e aU.S. Department of Agriculture - Agricultural Research Service, Center for Medical, Agricultural , and Veterinary...dU.S. Department of Agriculture - Agricultural Research Service, Natural Products Utilization Research Unit, The University of Mississippi, University

  15. 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.

  16. Sensitivity of Mycosphaerella graminicola isolates to demethylation-inhibiting (DMI) fungicides

    DEFF Research Database (Denmark)

    Ronis, Antanas; Jørgensen, Lise Nistrup; Semaskiene, Roma

    2014-01-01

    Mycosphaerella graminicola (Fuckel) J. Schröt. (anamorph Zymoseptoria tritici (Desm.) Quaedvlieg & Crous) causes Septoria leaf blotch disease of wheat. The disease can be responsible for yield losses of 30–50% and, when severe, requires management with a fungicide. Single picnidia isolates...... collected from different locations of Lithuania were tested in vitro for sensitivity to demethylation-inhibiting (DMI) fungicides epoxiconazole, cyproconazole and prothioconazole. Fungicide concentrations were chosen from the proposed Fungicide Resistance Action Committee (FRAC) methods. Microtitre plates...... that fungicides epoxiconazole and prothioconazole significantly reduced the area under the disease progress curve (AUDPC) values of Septoria leaf blotch compared with untreated plots in winter wheat. In most cases, a single fungicide application significantly increased grain yield and a thousand grain weight...

  17. IN-VITRO EVALUATION OF FUNGICIDES, BIOCONTROL AGENTS AND PLANT EXTRACTS AGAINST RICE SHEATH BLIGHT PATHOGEN RHIZOCTONIA SOLANI

    Directory of Open Access Journals (Sweden)

    P. Srinivas

    2014-02-01

    Full Text Available Of the fourteen fungicides of different groups evaluated in-vitro against Rhizoctonia solani , Metalaxyl (0.1%, Mancozeb (0.1%, Tricyclazole (0.1%, Thiophenate methyl (0.1%, Carbendizm+ Mancozeb (0.1% were proved to be most effective in inhibiting the growth of the fungus. Among the bio-agents screened, Trichoderma viride was most effective in restricting the growth of Rhizoctonia solani followed by Penicillium notatum where as Aspergillus niger was proved least effective. Among the thirteen plant extracts evaluated garlic extract (10% was most effective in inhibiting the growth of fungus followed by calotropis (10%. Datura leaf extract (10% was found to be least effective in inhibiting the growth of Rhizoctonia solani.

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

    OpenAIRE

    Maria Celeste Dias

    2012-01-01

    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 ...

  19. Degradation of Kresoxim-Methyl in Water: Impact of Varying pH, Temperature, Light and Atmospheric CO2 Level.

    Science.gov (United States)

    Khandelwal, Ashish; Gupta, Suman; Gajbhiye, Vijay T; Varghese, Eldho

    2016-01-01

    In the present investigation, persistence of kresoxim-methyl (a broad spectrum strobilurin fungicide) was studied in water. Results revealed that kresoxim-methyl readily form acid metabolite. Therefore, residues of kresoxim-methyl were quantified on the basis of parent molecule alone and sum total of kresoxim-methyl and its acid metabolite. In water, influence of various abiotic factors like pH, temperature, light and atmospheric carbon dioxide level on dissipation of kresoxim-methyl was studied. The half life value for kresoxim-methyl and total residue varied from 1 to 26.1 and 6.1 to 94.0 days under different conditions. Statistical analysis revealed the significant effect of abiotic factors on the dissipation of kresoxim-methyl from water.

  20. 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.

  1. 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.

  2. Dye-sensitized photodegradation of the fungicide carbendazim and related benzimidazoles.

    Science.gov (United States)

    Escalada, Juan P; Pajares, Adriana; Gianotti, José; Massad, Walter A; Bertolotti, Sonia; Amat-Guerri, Francisco; García, Norman A

    2006-10-01

    The present work studies the visible-light-promoted photodegradation of the colorless fungicide carbendazim (methyl 2-benzimidazolecarbamate) and several 2-substituted benzimidazoles (SBZ's), in water or water-methanol solution, in the presence of air and, as a photosensitizer, the synthetic xanthene dye Rose Bengal (RB) or the natural pigment riboflavin (Rf). The results indicate that the degradation of each particular SBZ depends on its chemical structure and on the sensitizer employed. In the presence of RB, the degradation always operates via a singlet molecular oxygen (O(2)((1)Delta(g)))-mediated mechanism, through a highly efficient process, as deduced from the comparison of the rate constants for physical and chemical quenching of O(2)((1)Delta(g)). In the presence of Rf, the visible-light irradiation of any of the studied SBZ's produces a series of competitive processes that depend on the relative concentrations of Rf and SBZ. These processes include the quenching of excited singlet and triplet Rf states by the SBZ and the generation of both O(2)((1)Delta(g)) and superoxide radical anion (O(2)(-)), the latter generated by electron transfer from excited Rf species to the dissolved oxygen. The overall result is the photodegradation of the SBZ and the photoprotection of the sensitizer.

  3. In vitro metabolism of the anti-androgenic fungicide vinclozolin by rat liver microsomes.

    Science.gov (United States)

    Sierra-Santoyo, Adolfo; Angeles-Soto, Esperanza; de Lourdes López-González, Ma; Harrison, Randy A; Hughes, Michael F

    2012-03-01

    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 (M1) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2). V, M1 and M2 have antiandrogenic properties by interacting with the androgen receptor. Data on V, M1 and M2 biotransformation are limited. Our objective was to characterize V metabolism by rat liver microsomes. V was incubated with non-treated adult male Long-Evans rat liver microsomes and NADPH. Several metabolites were detected following the extraction of incubate with acetonitrile and analysis by HPLC/DAD/MSD. One metabolite was identified as [3-(3,5-dichlorophenyl)-5-methyl-5-(1,2-dihydroxyethyl)-1,3-oxazolidine-2,4-dione] (M4), which was gradually converted to 3',5'-dichloro-2,3,4-trihydroxy-2-methylbutylanilide (M5). Both co-eluted in the same HPLC peak. Another metabolite ([M7]) was detected by UV but was unstable for mass spectral analysis. The K(M app) for co-eluted M4/M5 and [M7] was 53.7 and 135.4 μM, the V(max app) was 0.812 and 0.669 nmoles/min/mg protein, and CL(int) was 15.1 and 4.9 ml/min/g protein, respectively. Pilocarpine, orphenadrine and proadifen and anti-rat cytochrome P450 (CYP)2A, 2B and 3A antibodies inhibited M4/M5 and [M7] formation. These results indicate that V is efficiently metabolized by CYP. Determination of the metabolites of V will provide further insight into the relationship between toxicity and tissue dose of V and its metabolites.

  4. Methyl gallate

    Directory of Open Access Journals (Sweden)

    Silvina Pagola

    2009-02-01

    Full Text Available The crystal structure of the title compound (systematic name: methyl 3,4,5-trihydroxybenzoate, C8H8O5, is composed of essentially planar molecules [maximum departures from the mean carbon and oxygen skeleton plane of 0.0348 (10 Å]. The H atoms of the three hydroxyl groups, which function as hydrogen-bond donors and acceptors simultaneously, are oriented in the same direction around the aromatic ring. In addition to two intramolecular hydrogen bonds, each molecule is hydrogen bonded to six others, creating a three-dimensional hydrogen-bonded network.

  5. Synergistic Effects of Nanochitin on Inhibition of Tobacco Root Rot Disease.

    Science.gov (United States)

    Zhou, Yang; Jiang, Shijun; Jiao, Yongji; Wang, Hezhong

    2017-02-22

    Nanomaterials have great potential for use in various fields, due to their unique properties. In order to explore the bioactivity of nanochitin on tobacco, the effects of nanochitin suspensions on tobacco seed germination, seedling growth, and synergistic effects with fungicides were studied in indoor and field trials. Results showed that 0.004% (w/v) of nanochitin improved tobacco seed germination and shortened mean time to germination significantly; 0.005% (w/v) of nanochitin increased tobacco stem length, stem girth, leaf number and leaf area, and 0.001% (w/v) of nanochitin had synergistic effects on inhibition of tobacco root rot when mixed with metalaxyl mancozeb and thiophanate methyl fungicides. This indicates that nanochitin suspensions have a strong potential to protect tobacco from tobacco root rot diseases and reduce the use of chemical fungicides in tobacco plantations.

  6. Synthesis and Biological Activity of 3-Methyl-1H-pyrazole-4-carboxylic Ester Derivatives

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wei-Guang; LI Zheng-Ming; YUAN Ping-Wei; WANG Wen-Yan

    2001-01-01

    In search of novel pyrazole derivatives with bioactivity,a se-ries of 3-methyl- 1H-pyrazole-4-caboxylic ester derivatives were synthesized via α-oxoketene dithioacetals as starting ma-terial.The structures of al1 compounds prepared were con-firmed by 1HNMR, IR, MS and elemental analyses.Prelimi-nary bioassays indicated that some compounds showed fungici-dal activity against wheat rust,phoma asparagi and antiviral activity against TMV.

  7. TOXICITY PROFILES IN MICE TREATED WITH HEPATOTUMORIGENIC AND NON-HEPATOTUMORIGENIC TRIAZOLE CONAZOLE FUNGICIDES: PROPICONAZOLE, TRIADIMEFON, AND MYCLOBUTANIL

    Science.gov (United States)

    Conazoles comprise a class of fungicides used in agriculture and as pharmaceutical products. The fungicidal properties of conazoles are due to their inhibition of ergosterol biosynthesis. Certain conazoles are tumorigenic in rodents; both propiconazole and triadimefon are hepatot...

  8. Insecticidal and fungicidal activity of new synthesized chitosan derivatives.

    Science.gov (United States)

    Rabea, Entsar I; Badawy, Mohamed E I; Rogge, Tina M; Stevens, Christian V; Höfte, Monica; Steurbaut, Walter; Smagghe, Guy

    2005-10-01

    Chitosan, the N-deacetylated derivative of chitin, is a potential biopolysaccharide owing to its specific structure and properties. In this paper, we report on the synthesis of 24 new chitosan derivatives, N-alkyl chitosans (NAC) and N-benzyl chitosans (NBC), that are soluble in dilute aqueous acetic acid. The different derivatives were synthesized by reductive amination and analyzed by 1H NMR spectroscopy. A high degree of substitution (DS) was obtained with N-(butyl)chitosan (DS 0.36) at a 1:1 mole ratio for NAC derivatives and N-(2,4-dichlorobenzyl)chitosan (DS 0.52) for NBC derivatives. Their insecticidal and fungicidal activities were tested against larvae of the cotton leafworm Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae), the grey mould Botrytis cinerea Pers (Leotiales: Sclerotiniaceae) and the rice leaf blast Pyricularia grisea Cavara (Teleomorph: Magnaporthe grisea (Hebert) Barr). The oral feeding bioassay indicated that all the derivatives had significant insecticidal activity at 5 g kg(-1) in artificial diet. The most active was N-(2-chloro-6-fluorobenzyl)chitosan, which caused 100% mortality at 0.625 g kg(-1), with an estimated LC50 of 0.32 g kg(-1). Treated larvae ceased feeding after 2-3 days; the mechanism of action remains unknown. In a radial hyphal growth bioassay with both plant pathogens, all derivatives showed a higher fungicidal action than chitosan. N-Dodecylchitosan, N-(p-isopropylbenzyl)chitosan and N-(2,6-dichlorobenzyl)chitosan were the most active against B cinerea, with EC50 values of 0.57, 0.57 and 0.52 g litre(-1), respectively. Against P grisea, N-(m-nitrobenzyl)chitosan was the most active, with 77% inhibition at 5 g litre(-1). The effect of different substitutions is discussed in relation to insecticidal and fungicidal activity.

  9. 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

  10. 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...

  11. Comparative impact of artificial selection for fungicide resistance on Beauveria bassiana and Metarhizium brunncum

    Science.gov (United States)

    Hypocreales fungi such as Beauveria bassiana and Metarhizium anisopliae can be negatively affected by fungicides thereby reducing their biocontrol potential. The overall goal of this study was to investigate the impact of artificial selection for fungicide resistance on two commercial entomopathoge...

  12. Effects of the azole fungicide imazalil on the fathead minnow (Pimephales promelas) steroidogenesis pathway

    Science.gov (United States)

    Azole fungicides, used for both agriculture and human therapeutic applications may disrupt endocrine function of aquatic life. Azole fungicides are designed to inhibit the fungal enzyme lanosterol 14 á-demethylase (cytochrome P450 [CYP] 51). However, they can also interact...

  13. Bffects of foliar fungicides on the mycoflora of glumes of Triticum aestivum

    Directory of Open Access Journals (Sweden)

    Janusz Błaszkowski

    2014-08-01

    Full Text Available In the years 1983-1984. the effect of three foliar fungicides, i.e.. Bayleton 25 WP. Dithane M-45 and Funaben K on the mycoflora associated with glumus of spring Tritieum aestivum cv. Kolibri cultivated in the field was investigated. During each vegetative period, glumes were collected in the milky ripe of seeds. Fungi species associated with glumes were determined based of colonies isolated from glumes incubated in Petri dishes with potato glucose agar. The fungicide which reduced the most the overall number of fungal isolates was Bayleton 25 WP. The number of species was most reduced following Dithane M-45 application. The mycoflora of glumes which had been untreated and treated with fungicides was compared with fungicides-treated and fungicide-untreated seeds and leaves. The highest similarity in the mycoflora of fungicide-untreated plant parts was found when glumes and seeds were compared. The mycoflora of fungicide-treated glumes, leaves, and seeds varied. depending on the year and fungicide applied.

  14. Development and evaluation of adverse outcome pathways predicting adverse effects of conazole fungicides on avian species

    Science.gov (United States)

    Conazoles are a class of fungicides commonly used in agriculture and as pharmaceuticals to prevent the spread of fungus through inhibition of cytochrome P450 14á-demethylase (CYP51). However these fungicides are known to act promiscuously on other cytochrome P450 enzymes (...

  15. Can phyllosphere yeast explain the effect of scab fungicides on russeting of Elstar Apples?

    NARCIS (Netherlands)

    Gildemacher, P.R.; Heijne, B.; Houbraken, J.; Vromans, T.; Hoekstra, E.S.; Boekhout, T.

    2004-01-01

    In 1999 and 2000, the effects of scab fungicides on yeast composition and russeting of Elstar apples were assessed. Yeast composition of fungicide-treated and untreated young apple fruit with or without russet symptoms was investigated and enzyme activity of the yeasts was studied. Cryptococcus albi

  16. Cercospora leaf spot: monitoring and managing fungicide resistance in populations of Cercospora beticola in Michigan

    Science.gov (United States)

    Cercospora leaf spot (CLS, Cercospora beticola) is the most serious foliar disease of sugarbeet in Michigan and Ontario.Management of CLS depends on timely fungicide applications, disease forecasting prediction models and the use of CLS resistant sugar beet varieties. Fungicides have a dominant role...

  17. Fungicide resistance phenotypes in Botrytis cinerea populations from blueberries in California and Washington

    Science.gov (United States)

    Gray mold caused by Botrytis cinerea is a major postharvest disease of blueberries grown in the Central Valley of California (CA) and western Washington State (WA). Understanding fungicide- resistant phenotypes of B. cinerea is important to the development of preharvest fungicide programs for contro...

  18. Analysis of Turf Fungicides in Snow Melt Runoff by LC/MS

    Science.gov (United States)

    Fungicides are applied on turf grass, in autumn, to control snow mold in the north-central United States. Fungicides of varying chemical classes have been detected in snow melt runoff from turf. A multi-residue method for simultaneous sample extraction and analysis is needed to process a large quant...

  19. 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....

  20. Effect of Fungicides on the Reaction of Sorghum Hybrids to Anthracnose in Burleson County, Texas, 2012

    Science.gov (United States)

    The use of three fungicides to control grain mold/weathering and anthracnose on two sorghum hybrids NC+7R34 and Warner W851-DR was conducted during the 2012 growing season. Three fungicides Headline, Quilt Xcel, and Topguard were used. On May 26, plots were inoculated by putting 10 Colletotrichum ...

  1. Honey bee gut microbial communities are robust to the fungicide Pristine® consumed in pollen

    Science.gov (United States)

    Honeybees that consume pollen with sublethal levels of the fungicide Pristine® can have reduced pollen digestion, lower ATP synthesis and in many ways resemble malnourished bees. Reduced nutrient acquisition in bees exposed to Pristine® might be because this fungicide affects the composition of gut ...

  2. 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.

  3. 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

  4. The Evolution of Fungicide Resistance Resulting from Combinations of Foliar-Acting Systemic Seed Treatments and Foliar-Applied Fungicides: A Modeling Analysis.

    Science.gov (United States)

    Kitchen, James L; van den Bosch, Frank; Paveley, Neil D; Helps, Joseph; van den Berg, Femke

    2016-01-01

    For the treatment of foliar diseases of cereals, fungicides may be applied as foliar sprays or systemic seed treatments which are translocated to leaves. Little research has been done to assess the resistance risks associated with foliar-acting systemic seed treatments when used alone or in combination with foliar sprays, even though both types of treatment may share the same mode of action. It is therefore unknown to what extent adding a systemic seed treatment to a foliar spray programme poses an additional resistance risk and whether in the presence of a seed treatment additional resistance management strategies (such as limiting the total number of treatments) are necessary to limit the evolution of fungicide-resistance. A mathematical model was developed to simulate an epidemic and the resistance evolution of Zymoseptoria tritici on winter wheat, which was used to compare different combinations of seed and foliar treatments by calculating the fungicide effective life, i.e. the number of years before effective disease control is lost to resistance. A range of parameterizations for the seed treatment fungicide and different fungicide uptake models were compared. Despite the different parameterizations, the model consistently predicted the same trends in that i) similar levels of efficacy delivered either by a foliar-acting seed treatment, or a foliar application, resulted in broadly similar resistance selection, ii) adding a foliar-acting seed treatment to a foliar spray programme increased resistance selection and usually decreased effective life, and iii) splitting a given total dose-by adding a seed treatment to foliar treatments, but decreasing dose per treatment-gave effective lives that were the same as, or shorter than those given by the spray programme alone. For our chosen plant-pathogen-fungicide system, the model results suggest that to effectively manage selection for fungicide-resistance, foliar acting systemic seed treatments should be included as

  5. Fungicides and the effects of mycotoxins on milling fractions of irrigated rice.

    Science.gov (United States)

    Dors, Giniani Carla; Caldas, Sergiane Souza; Hackbart, Helen Cristina dos Santos; Primel, Ednei Gilberto; Fagundes, Carlos Alberto Alves; Badiale-Furlong, Eliana

    2013-02-27

    This study aimed to evaluate the effect of fungicides on rice cultivation, regarding the occurrence and the distribution of mycotoxins in fractions of the processed grain, by a validated chromatographic method. A method based on extraction with acetonitrile:water, determination by HPLC-DAD, and confirmation by LC-MS was validated before the mycotoxin evaluation. Control samples and samples to which triazole fungicides had been applied were collected from experimental fields for four years. Results showed that 87% of the samples were contaminated with deoxynivalenol or zearalenone, and that all samples treated with fungicide were contaminated with some of these mycotoxins. Aflatoxin B(1) and ochratoxin A were found in 37% of the samples; half of them had been treated with fungicide. Therefore, fungicides tend to be stressors for toxigenic fungi found in the fields.

  6. 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.

  7. Sustained release of fungicide metalaxyl by mesoporous silica nanospheres

    Science.gov (United States)

    Wanyika, Harrison

    2013-08-01

    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.

  8. 2-hydroxyisocaproic acid is fungicidal for Candida and Aspergillus species.

    Science.gov (United States)

    Sakko, M; Moore, C; Novak-Frazer, L; Rautemaa, V; Sorsa, T; Hietala, P; Järvinen, A; Bowyer, P; Tjäderhane, L; Rautemaa, R

    2014-04-01

    The amino acid derivative 2-hydroxyisocaproic acid (HICA) is a nutritional additive used to increase muscle mass. Low levels can be detected in human plasma as a result of leucine metabolism. It has broad antibacterial activity but its efficacy against pathogenic fungi is not known. The aim was to test the efficacy of HICA against Candida and Aspergillus species. Efficacy of HICA against 19 clinical and reference isolates representing five Candida and three Aspergillus species with variable azole antifungal sensitivity profiles was tested using a microdilution method. The concentrations were 18, 36 and 72 mg ml(-1) . Growth was determined spectrophotometrically for Candida isolates and by visual inspection for Aspergillus isolates, viability was tested by culture and impact on morphology by microscopy. HICA of 72 mg ml(-1) was fungicidal against all Candida and Aspergillus fumigatus and Aspergillus terreus isolates. Lower concentrations were fungistatic. Aspergillus flavus was not inhibited by HICA. HICA inhibited hyphal formation in susceptible Candida albicans and A. fumigatus isolates and affected cell wall integrity. In conclusion, HICA has broad antifungal activity against Candida and Aspergillus at concentrations relevant for topical therapy. As a fungicidal agent with broad-spectrum bactericidal activity, it may be useful in the topical treatment of multispecies superficial infections.

  9. Ecotoxicity of climbazole, a fungicide contained in antidandruff shampoo.

    Science.gov (United States)

    Richter, Elisabeth; Wick, Arne; Ternes, Thomas A; Coors, Anja

    2013-12-01

    Emerging pollutants such as personal care products can reach the environment via effluents from wastewater treatment plants (WWTPs) and digested sludge. Only recently, the antidandruff agent and antimycotic climbazole was detected for the first time in a WWTP effluent with concentrations up to 0.5 µg/L. Climbazole acts as a C14-demethylase inhibitor (DMI) fungicide and thus has a high efficacy against fungi, but knowledge of its potential environmental impact is lacking. Therefore, the aim of the present study was to characterize climbazole's ecotoxicity by conducting standard biotests with organisms representing different trophic levels from the aquatic as well as the terrestrial ecosystems. It was found that the toxicity of climbazole is mostly similar to that of other DMI fungicides, whereas it proved to be particularly toxic to primary producers. The lowest median effective concentrations (EC50s) were determined for Lemna minor, at 0.013 mg/L (biomass yield), and Avena sativa, at 18.5 mg/kg soil dry weight (shoot biomass). Reduction of frond size in water lentils and shoot length in higher plants suggested an additional plant growth-retarding mode of action of climbazole. In addition, it was demonstrated here that for an ionizable compound such as climbazole, the soil pH can have a considerable influence on phytotoxicity. © 2013 SETAC.

  10. Molecular mechanism of resistance of Fusarium fujikuroi to benzimidazole fungicides.

    Science.gov (United States)

    Chen, Zihao; Gao, Tao; Liang, Shuping; Liu, Kexue; Zhou, Mingguo; Chen, Changjun

    2014-08-01

    Although carbendazim (MBC) and other benzimidazole fungicides have effectively controlled bakanae disease of rice (which is caused by Fusarium fujikuroi, F. proliferatum, and F. verticillioides) in the past, MBC resistance has become common. Previous research has shown that MBC resistance results from a mutation in the β1 -tubulin (β1 tub) gene in F. verticillioides. However, MBC resistance in F. fujikuroi, a predominant species in China, does not result from a mutation in the β1 tub. The molecular mechanism of F. fujikuroi resistance against benzimidazole fungicides is poorly understood. In this study, we determined that although β1 tub and β2 -tubulin (β2 tub) in F. fujikuroi have high homology with β1 tub and β2 tub in F. verticillioides, MBC resistance in F. fujikuroi results from mutations in β2 tub [GAG(Glu)→GTG(Val) at codon 198, TTC(Phe)→TAC(Tyr) at codon 200, and GGC(Gly)→GGT(Gly) at codon 235] but not in β1 tub. Δβ2 tub (β2 tub deletion) mutants were highly sensitive to MBC, produced fewer conidia and were less virulent than parental strains. Complementation of the Δβ2 tub mutants with a copy of the whole β2 tub locus from their parental strains restored the level of MBC resistance (or sensitivity) to that of the parental strain.

  11. 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.

  12. Vacuole-targeting fungicidal activity of amphotericin B

    Directory of Open Access Journals (Sweden)

    Akira eOgita

    2012-03-01

    Full Text Available Invasive fungal infections are recognized as major threats to patients with immune depression as well as those with cancer chemotherapy. Amphotericin B (AmB, a classical antifungal agent with a polyene macrolide structure, is widely used for the control of serious fungal infections. However, the clinical use of this antibiotic is limited by the treatment-associated side effects and the appearance of resistant strains. AmB lethality has been generally elucidated by the alteration of plasma membrane ion permeability due to its specific binding to plasma membrane ergosterol. While, the recent studies with Saccharomyces cerevisiae and Candida albicans reveals the vacuole disruptive action as another cause of AmB lethality on the basis of its marked amplification in combination with allicin, an allyl sulfur compound from garlic. Indeed, AmB causes a serious structural damage to the vacuole membrane at a lethal concentration, and even at a non-lethal concentration in combination with allicin. Such an enhancement effect of allicin is dependent on an inhibition of ergosterol-trafficking from the plasma membrane to the vacuole membrane, which is considered to be a cellular response to protect against the vacuole membrane disintegration. Allicin can also decrease the minimum fungicidal concentration of AmB against the pathogenic fungi C. albicans and Aspergillus fumigatus, as is the case of S. cerevisiae. The synergistic fungicidal activities of AmB and allicin may have significant implications in the development of the vacuole-targeting chemotherapy against fungal infections.

  13. Development of competitive immunoassays to hydroxyl containing fungicide metabolites.

    Science.gov (United States)

    Gough, Kevin C; Jarvis, Shila; Maddison, Ben C

    2011-01-01

    This paper describes the isolation of monoclonal antibodies and the development of competitive immunoassays to pesticide metabolites of the fungicides imazalil, carbendazim and thiabendazole. The metabolite specific hydroxyl residues were used as the reactive group with which to link the metabolite to the carrier proteins Keyhole Limpet Haemocyanin (KLH) and Bovine Serum Albumin (BSA). In each case immune responses in mice were raised and monoclonal antibodies were produced. Antibodies were developed into competitive ELISAs to the appropriate metabolite. The antibody raised to a metabolite of imazalil was optimised into a competitive ELISA format which had an assay IC50 of 7.5 μg/L and a limit of detection (LOD) of 1.1 μg/L. A single antibody isolated against the metabolite of carbendazim had assay IC50s of 3.2 and 2.7 μg/L for the metabolites of carbendazim and thiabendazole respectively with an LOD of 0.38 μg/L for both. These sensitive immunoassays may have application in the monitoring of human exposure to these fungicide residues either by occupational or non-occupational routes.

  14. FUNGICIDE APPLICATION FOR MAINTAINING POSTHARVEST QUALITY IN TOMATO FRUITS

    Directory of Open Access Journals (Sweden)

    D. M. Vani

    2014-07-01

    Full Text Available Tomato fruits are usually consumed soon after harvest, however, as they are mainly comprised of water, and its walls are fragile, facilitates the emergence of diseases, making necessary the use of preventive measures in the field in order to reduce incidence of disease. The objective is then to evaluate the effect of foliar application of fungicides on the final quality of tomato fruits in postharvest. There were 13 applications of foliar fungicides Azoxystrobin+Cyproconazol and Boscalida, 7 applications Tebuconazol+Trifoxistrobin and 17 applications of Propamocarb+Fluopicolide (Control. We analyzed the incidence of Fusarium sp. in fruits, decay percentage of fruit weight (g and Brix. For incidence of Fusarium sp. in fruits, treatments Tebuconazol+Trifoxistrobin and Azoxistrobin+Ciproconazol reduced by 14.3%, the pathogen in fruits. There was a decrease of 82% in the deterioration of fruits treated with Tebuconazol+Trifoxistrobin and 91% in those treated with Azoxistrobin+Ciproconazol. As for the weight gain, treatments Tebuconazol+Trifoxistrobin, Boscalida and Azoxistrobin+Ciproconazol reduced the weight gain in 8.12%, 20.8% and 38.8%, respectively, compared to the control. ° Brix values of fruits treated with Tebuconazol+Trifoxistrobin and Boscalida were higher than those treated with Azoxistrobin+Ciproconazol and Control (Propamocarb+Fluopicolide. It is concluded that the treatment carried out with Tebuconazol+Trifoxistrobin afforded the greatest benefits in maintaining the tomato fruits in harvest.

  15. The inter-generic fungicidal activity of Xanthophyllomyces dendrorhous.

    Science.gov (United States)

    Baeza, Marcelo; Flores, Oriana; Carrasco, Mario; Rozas, Juan Manuel; Oviedo, Vicente; Barahona, Salvador; Cifuentes, Víctor

    2010-12-01

    In this study, the existence of intra-specific and inter-generic fungicidal activity in Xanthophyllomyces dendrorhous and Phaffia rhodozyma strains isolated from different regions of the earth was examined. Assays were performed under several culture conditions, showing that all the analyzed X. dendrorhous and P. rhodozyma strains have killing activity against Kloeckera apiculata, Rhodotorula sloffiae, and R. minuta. This activity was greater in rich media at a pH from 4.6 to 5.0. Extracellular protein extracts with fungicidal activity were obtained from cultures of all strains, and their characterization suggested that a protein of 33 kDa is the antifungal factor. According to peptide mass fingerprinting and an analysis of the results with the MASCOT search engine, this protein was identified as an aspartic protease. Additionally, extrachromosomal double-stranded DNA elements (dsDNAs) were observed in all X. dendrorhous and P. rhodozyma strains. Although there is a high variability, two dsDNAs of 5.4 and 6.8 kb are present in all strains.

  16. 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.

  17. Efficacy of Fungicides and Spatial Distribution of Angular Leaf Spot on Tripterygium wilfordii Infected by Pseudocercospra elaeodendri%雷公藤角斑病菌的室内毒力测定及病害空间分布格局研究

    Institute of Scientific and Technical Information of China (English)

    谢婉凤; 郭文硕; 冯丽贞; 苏良玉; 叶小真; 黄秀萍; 刘金燕

    2014-01-01

    用8种真菌杀菌剂防治雷公藤角斑病,室内孢子毒力试验表明:孢子萌发抑制效果以75%百菌清可湿性粉剂最好, EC50=0.49 mg · L-1, EC=0.78 mg · L-1,其次是25%腐霉利可湿性粉剂,80%代森锰锌可湿性粉剂。浓度70 mg · L-1嘧霉胺及100 mg · L-1的异菌脲、甲基硫菌灵、三唑酮对分生孢子萌发的抑制率均小于10%。通过聚集度指标法的测定、Iwao的回归分析法和 Taylor 的幂法则对雷公藤角斑病的空间分布格局进行研究,结果表明,雷公藤角斑病病株在林间为均匀分布。%Efficacy of 8 fungicides was examined in vitro on the germination of Pseudocercospra elaeodendri .The best effect of the fungicides was the 75% mass fraction chlorothalonil WP with EC50 =0.49 mg · L -2 ,EC= 0.78 mg · L -2 ,followed by the 25% mass fraction procymidone thiram WP ,and then ,the 80% mass fraction mancozeb WP .Spore germination inhibition rates of < 10% were found for pyrimethanil (70 mg · L -2 ) ,iprodione (100 mg · L -1 ) ,thiophanate-metlyl (100 mg · L -1 ) and tradimefon (100 mg · L -1 ) after 7 h incubation .Based on the aggregation indices ,Iwao′s regression and Taylor′s power law ,the spatial distribution pattern of the angular leaf spot of Tripterygium wilfordii was found to be uniform in the area′s forests .

  18. Inibição do desenvolvimento de Penicillium expansum (Link Thom. por fungicidas, in vitro In vitro development inhibition of Penicillium expansum (Link Thom. by fungicides

    Directory of Open Access Journals (Sweden)

    Ivan Francisco Dressier da Costa

    1996-12-01

    Full Text Available Para avaliar a eficiência de quatro fungicidas sobre a inibição do desenvolvimento de Penicillium expansum, foi desenvolvido um experimento em laboratório na Universidade Federal de Santa Maria, RS, durante o ano de 1992. Foram testados os princípios alivos Tiabendazole, Tiofanato Metílico, Iprodione e Imazalil, em cinco concentrações sobre dois isolados do fungo, sendo um resistente e outro sensível aos benzimidazóis. Foram testadas as concentrações de 0,1; 0,5; 1,0; 5,0 e l0.0mg/ml dos princípios ativos, e as avaliações/oram realizadas com 0; 48;96, 144 e 192 horas após as repicagens. Os resultados demonstraram que não houve diferença na inibição do desenvolvimento entre os fungicidas sobre o isolado sensível, porém ocorreu diferença entre os produtos para o isolado resistente, sendo o Tiabendazole e o Tiofanato Metílico os que apresentaram a menor eficiência. O Iprodione mostrou-se eficiente sobre os dois isolados e, o Imazalil inibiu completamente o desenvolvimento do fungo nas concentrações de 5,0 e 10mg/ml até as 192 horas.This experiment was conducted to evaluate lhe effïciency of four fungicides in the development inhibition of Penicillium expansum. A laboratory experiment was carried out in 1993, at Federal University of Santa Maria, RS. The fungicides Thiabendazol, Methyl Tiophanate, Iprodione and Imazalil, infive concentrations of active ingredients (0.1; 0.5; 1.0; 5.0 and 10mg/ml on two isolates of the fungus were tested. The diametersof pathogen colonies were measured at 0; 48; 96, 144 and 192 hours after pathogen plating. There were no statistical differences in the inhibitions of benzimidazols compounds to sensible isolate among fungicides. There were significant difference for the resistant isolate, with less effïcience for Thiabendazol and Methyl Tiophanate fungicides. The Iprodione showed effïcience on the two isolates, and only Imazalil demonstrated complete inhibition of Penicillium expansum

  19. Baseline sensitivity to proquinazid in Blumeria graminis f. sp. tritici and Erysiphe necator and cross-resistance with other fungicides.

    Science.gov (United States)

    Genet, Jean-Luc; Jaworska, Grazyna

    2009-08-01

    Proquinazid is a new quinazolinone fungicide from DuPont registered in most European countries for powdery mildew control in cereals and vines. The aim of this paper is to present baseline sensitivity data in populations of Blumeria graminis f. sp. tritici EM Marchal and Erysiphe necator (Schw) Burr as well as results from cross-resistance studies with other fungicides. Proquinazid exhibited a high intrinsic activity on B. graminis f. sp. tritici isolates at rates ranging from 0.000078 to 0.02 mg L(-1). Erysiphe necator isolates were comparatively less sensitive to proquinazid, with EC(50) values ranging from 0.001 to 0.3 mg L(-1). Proquinazid controlled equally well B. graminis f. sp. tritici isolates sensitive and resistant or less sensitive to tebuconazole, fenpropimorph, fenpropidin, cyprodinil and kresoxim-methyl. A positive correlation (r = 0.617) between quinoxyfen and proquinazid sensitivities was found among 51 B. graminis f. sp. tritici isolates. Quinoxyfen-resistant B. graminis f. sp. tritici isolates were slightly less sensitive to proquinazid than the quinoxyfen-sensitive isolates; however, proquinazid remained much more active than quinoxyfen on these isolates. A stronger sensitivity relationship (r = 0.874) between proquinazid and quinoxyfen was found among 65 E. necator isolates tested in a leaf disc assay. The sensitivity values for proquinazid were significantly lower than those for quinoxyfen, confirming the higher intrinsic activity of proquinazid on both pathogens. Given the history of resistance development in powdery mildew and the observed sensitivity relationship with quinoxyfen, specifically in E. necator, we conclude that the risk of resistance developing to proquinazid might be influenced by the use of quinoxyfen. Based on these results, the authors recommend that proquinazid and quinoxyfen be managed together for resistance management.

  20. 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.

  1. RELATIONSHIP BETWEEN PATHOGENICITY AND FUNGICIDE TOLERANCE IN THE WHEAT PATHOGEN MYCOSPHAERELLA GRAMINICOLA.

    Science.gov (United States)

    Siah, A; Deweer, C; Tisserant, B; Randoux, B; Halama, P; Reignault, Ph

    2015-01-01

    Septoria tritici blotch caused by Mycosphaerella graminicola (anamorph: Zymoseptoria tritici) is currently the most devastating disease on wheat crops worldwide, especially in regions with suitable climate conditions such as Western Europe. Pathogen control relies mainly on the use of fungicides and resistant cultivars. However, the durability of chemical and genetic control strategies is increasingly compromised in the field since the fungus frequently develops resistance to fungicides and overcomes host resistance. Here, we assessed the association between pathogenicity and fungicide tolerance in eighteen different M. graminicola strains isolated in 2009 from Northern France. These strains were chosen because they exhibited in preliminary experiments a wide range of in vitro tolerance levels against six demethylation inhibitors (epoxiconazole, cyproconazole, fluquinconazole, propiconazole, prothioconazole and pyrefenox). Inoculation of the Scorpion susceptible wheat cultivar in the greenhouse with these strains revealed a great variability in their pathogenicity levels (disease symptoms ranged from 0 to 66% of leaf area bearing pycnidia). Interestingly, strains with high fungicide tolerance levels caused overall the highest disease symptoms (45% of diseased leaf area on average) when compared to those with low fungicide tolerance levels (22% of diseased leaf area on average), thus confirming the association between pathogenicity level and fungicide tolerance in M. graminicola. The occurrence and selection in the field of fungal genotypes combining both pathogenicity and fungicide resistance should be taken into account in disease management strategies.

  2. The rising threat of fungicide resistance in plant pathogenic fungi: Botrytis as a case study.

    Science.gov (United States)

    Hahn, Matthias

    2014-10-01

    The introduction of site-specific fungicides almost 50 years ago has revolutionized chemical plant protection, providing highly efficient, low toxicity compounds for control of fungal diseases. However, it was soon discovered that plant pathogenic fungi can adapt to fungicide treatments by mutations leading to resistance and loss of fungicide efficacy. The grey mould fungus Botrytis cinerea, a major cause of pre- and post-harvest losses in fruit and vegetable production, is notorious as a 'high risk' organism for rapid resistance development. In this review, the mechanisms and the history of fungicide resistance in Botrytis are outlined. The introduction of new fungicide classes for grey mould control was always followed by the appearance of resistance in field populations. In addition to target site resistance, B. cinerea has also developed a resistance mechanism based on drug efflux transport. Excessive spraying programmes have resulted in the selection of multiresistant strains in several countries, in particular in strawberry fields. The rapid erosion of fungicide activity against these strains represents a major challenge for the future of fungicides against Botrytis. To maintain adequate protection of intensive cultures against grey mould, strict implementation of resistance management measures are required as well as alternative strategies with non-chemical products.

  3. Evaluation of cytotoxic and genotoxic activity of fungicide formulation Tango(®) Super in bovine lymphocytes.

    Science.gov (United States)

    Schwarzbacherová, Viera; Wnuk, Maciej; Lewinska, Anna; Potocki, Leszek; Zebrowski, Jacek; Koziorowski, Marek; Holečková, Beáta; Šiviková, Katarína; Dianovský, Ján

    2017-01-01

    Tango(®) Super is a two-compound fungicide formulation widely employed in grain protection. However, details of Tango(®) Super effects on cell cultures have not been fully investigated. In this study, bovine lymphocytes were exposed to a concentration range 0.5; 1.5; 3; 6; and 15 μg mL(-1) for 4 h to assess the cytotoxicity and genotoxicity of the fungicide. Our experiments revealed that this fungicide treatment reduced cell viability, decreased cell proliferation and provoked apoptotic cell death. Cell cycle analysis showed predominant accumulation of cells in the G0/G1 phase of the cell cycle. The fungicide was able to induce mitochondrial superoxide production accompanied by elevated levels of carbonylated proteins and changes in the lipid membrane composition. The fungicide did not induce micronuclei production, but stimulated both DNA double-strand breaks and the formation of p53 binding protein, which is accumulated during the DNA repair process at the site of double-strand breaks. Based on the obtained data we suppose that the fungicide-induced DNA damage is the result of oxidative stress, which may contribute to higher occurrence of apoptotic cell death. Because ergosterol biosynthesis-inhibiting fungicides are widely used in agriculture to ensure higher crop yields and may cause health impairment of animals and humans, there is a need for further testing to elucidate their potential genotoxic effects using in vivo and/or in vitro systems.

  4. A convenient method to generate methylated and un-methylated control DNA in methylation studies

    Directory of Open Access Journals (Sweden)

    Mehdi Manoochehri

    2013-09-01

    Full Text Available Methylated and un-methylated control DNA is an important part of DNA methylation studies. Although human and mouse DNA methylation control sets are commercially available, in case of methylation studies on other species such as animals, plants, and bacteria, control sets need to be prepared. In this paper a simple method of generating methylated and un-methylated control DNA is described. Whole genome amplification and enzymatic methylation were performed to generate un-methylated and methylated DNA. The generated DNA were confirmed using methylation sensitive/dependant enzymes, and methylation specific PCR. Control reaction assays confirmed the generated methylated and un-methylated DNA.

  5. 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.

  6. 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

  7. 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.

  8. Azole fungicides disturb intracellular Ca2+ in an additive manner in dopaminergic PC12 cells.

    Science.gov (United States)

    Heusinkveld, Harm J; Molendijk, Jeffrey; van den Berg, Martin; Westerink, Remco H S

    2013-08-01

    Humans are exposed to complex mixtures of pesticides and other compounds, mainly via food. Azole fungicides are broad spectrum antifungal compounds used in agriculture and in human and veterinary medicine. The mechanism of antifungal action relies on inhibition of CYP51, resulting in inhibition of fungal cell growth. Known adverse health effects of azole fungicides are mainly linked to CYP inhibition. Additionally, azole fungicide-induced neurotoxicity has been reported, though the underlying mechanism(s) are largely unknown. We therefore investigated the effects of a group of six azole fungicides (imazalil, flusilazole, fluconazole, tebuconazole, triadimefon, and cyproconazole) on cell viability using a combined alamar Blue/CFDA-AM assay and on oxidative stress using a H2-DCFDA fluorescent assay. As calcium plays a pivotal role in neuronal survival and functioning, effects of these six azole fungicides and binary and quaternary mixtures of azole fungicides on the intracellular calcium concentration ([Ca(2+)]i) were investigated using single-cell fluorescence microscopy in dopaminergic PC12 cells loaded with the calcium-sensitive fluorescent dye Fura-2. Only modest changes in cell viability and ROS production were observed. However, five out of six azole fungicides induced a nonspecific inhibition of voltage-gated calcium channels (VGCCs), though with varying potency. Experiments using binary IC20 and quaternary IC10 mixtures indicated that the inhibitory effects on VGCCs are additive. The combined findings demonstrate modulation of intracellular Ca(2+) via inhibition of VGCCs as a novel mode of action of azole fungicides. Furthermore, mixtures of azole fungicides display additivity, illustrating the need to take mixture effects into account in human risk assessment.

  9. 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

  10. 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

    .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 variance between species and among the 6 tested isolates of Penicillium roqueforti var. roqueforti......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...

  11. In vitro Toxicity of Fungicides of Different Mode of Action to Agaricus bisporus (Lange Imbach

    Directory of Open Access Journals (Sweden)

    Ivana Potočnik

    2009-01-01

    Full Text Available Isolates of Agaricus bisporus strains F56 and U3 were tested for sensitivity to several selected fungicides in vitro. The analysis showed that flusilasole + carbendazim and cyproconazole + carbendazim were the most toxic fungicides to A. bisporus strain F56 with respective EC50 values of 0.04 and 0.23 mg/l. The least toxic fungicides were carbendazim (EC50 = 16.58 mg/l and trifloxystrobin (EC50 = 20.69 mg/l to A. bisporus F56 and benomyl (EC50 = 14.99 mg/l to A. bisporus U3.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. The effect of selected fungicides on survival of Agrobacterium tumefaciens in various kinds of soils

    Directory of Open Access Journals (Sweden)

    Stanisław Barczyński

    2013-12-01

    Full Text Available The effect of 10 fungicides on survival of A. tumefaciens in various types of soils was studied. In fertile, nonsterile soil Dithane M-45 (mancozeb, Euparen 50 WP (tolyfluanid, Kaptan 50 WP (captan and Ridomil Gold 80 WP (metalaxyl at concentration of 1000 ppm showed the highest antibacterial activity. Similar trends in activity of these fungicides occurred in fertile, sterile soil, however a little lower in case of Kaptan and Euparen. In most of investigated soils Befran 25 SL (imimnoctadyne, Syllit 65 WP (dodine and Thiram Granulfo 80 WG (thiram increased bacteria number. In sandy acidic soil (pH 3,5 all tested fungicides totally eliminated bacteria. On the other hand in sandy neutral soil only Dithane, Euparen, Kaptan and Ridomil showed such activity. Ten fold decrease of fungicides concentration generally did not influence Kaptan and Ridomil effectiveness but it decreased the activity of Dithane and Euparen.

  17. 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 ...

  18. Gene Expression Profiling in Liver and Testis of Rats to Characterize the Toxicity of Triazole Fungicides

    Science.gov (United States)

    Four triazole fungicides were studied using toxicogenomic techniques to identify potential mechanisms of action. Adult male Sprague-Dawley rats were dosed for 14 days by gavage with fluconazole, myclobutanil, propiconazole, or triadimefon. Following exposure, serum was collected ...

  19. USING PHARMACOKINETIC DATA TO INTERPRET METABOLOMIC CHANGES IN CD-1 MICE TREATED WITH TRIAZOLE FUNGICIDES

    Science.gov (United States)

    Triazoles are a class of fungicides widely used in both pharmaceutical and agricultural applications. These compounds elicit a variety of toxic effects including disruption of normal metabolic processes such as steroidogenesis. Metabolomics is used to measure dynamic changes in e...

  20. Resistance behaviour of Septoria tritici to some fungicides in the territory of the Czech Republic

    Directory of Open Access Journals (Sweden)

    Ludvik Tvaružek

    2012-12-01

    Full Text Available Reduction of colony diameter using two DMI-fungicides and one strobilurine fungicide was evaluated in the Septoria tritici population. In an in vitro assay, 57 strains of S. tritici originating from different parts of the Czech Republic were grown on agar plates containing different concentrations of fungicides. The mean EC50 values of strains were analysed for flusilazole (Capitain, metconazole (Caramba and one strobilurine fungicide: azoxystrobin (Amistar. ED 50 values for metconazole were low. There were highly significant correlation in reaction of pathogen strains to metconazole and flusilazole. Some isolates showed significant higher level of resistance to azoxystrobin. The data will be used in a continuing survey of resistance development in the S. tritici population originating from the territory of the Czech Republic.

  1. 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

  2. Effects of fludioxonil and pyrimethanil, two fungicides used against Botrytis cinerea, on carbohydrate physiology in Vitis vinifera L.

    Science.gov (United States)

    Saladin, Gaëlle; Magné, Christian; Clément, Christophe

    2003-10-01

    In Vitis vinifera L, photosynthesis and photosynthate partitioning are affected in the presence of fludioxonil and pyrimethanil, two fungicides commonly used in vineyards against Botrytis cinerea Pers. However, the effects were found to be different according to the model studied: plantlets (cv Chardonnay) grown in vitro, fruiting cuttings (cv Chardonnay) and plants grown in vineyards (cvs Chardonnay, Pinot noir and Pinot Meunier). In the plantlets grown in vitro, both fungicides decreased gas exchanges, photosynthetic pigment and starch concentrations in the leaves, whereas soluble carbohydrates transiently accumulated, suggesting that plantlets mobilised starch in response to photosynthesis inhibition caused by fungicides. In the fruiting cuttings, the fungicides did not affect photosynthesis, although fludioxonil caused starch decrease in parallel with sucrose accumulation, suggesting that the fungicide effects were of lower intensity than in vitro. Conversely, in vineyard, the two fungicides stimulated photosynthesis and increased pigment concentrations in the three vine cultivars tested. In the meantime, glucose, fructose and starch levels of the leaves declined after fungicide exposure, whereas sucrose accumulated, indicating that sucrose synthesis increased in the leaves following the fungicide treatment. Among the three varieties, Chardonnay was the most sensitive to the fungicides as revealed by the intensity of the responses and the longer period for recovery. In vineyard, the results suggested that the two fungicides, in addition to inhibiting B cinerea development, had a beneficial effect on vine physiology through the stimulation of leaf carbon nutrition, which may further enable the plant to rapidly make use of its defence reactions.

  3. 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.

  4. Fungi and bacteria. [fungicide and bactericide measures for spacecraft in tropical regions

    Science.gov (United States)

    Daniels, G. E.

    1973-01-01

    Spacecraft equipment is usually protected from fungi and bacteria by incorporating a fungicide-bactericide in the material, by a fungicide-bactericide spray, or by reducing the relative humidity to a degree where growth will not take place. A unique method to protect delicate, expensive bearings in equipment was to maintain a pressure (with dry air or nitrogen) slightly above the outside atmosphere (few millibars) within the working parts of the equipment, thus preventing fungi from entering equipment.

  5. Impact of fungicides used for wheat treatment on button mushroom cultivation

    OpenAIRE

    Ivana Potočnik; Jelena Vukojević; Mirjana Stajić; Dejana Kosanović; Emil Rekanović; Miloš Stepanović; Svetlana Milijašević-Marčić

    2012-01-01

    Little information is currently available on the potential environmental risks that fungicides applied during wheat cultivation and remaining in straw may have for mushroom production. The substrate for many cultivated mushrooms is mostly based on cereal straw. This review aimed to answer the question whether residues of the fungicides commonly used in wheat production and remaining in straw could be directly or indirectly responsible for changes in yields ...

  6. 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. 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...

  7. Control of angular leaf spot on dry beans with fungicides and its effect on plant production

    OpenAIRE

    Deman, Luis Alfredo Raue; Maringoni, Antonio Carlos [UNESP

    2012-01-01

    The angular leaf spot of dry bean caused by the fungus Phaeoisairopsis griseola is a very important disease on dry bean crops in Brazil. In propitious weather conditions, susceptible cultivars have significant losses due to this disease. In these conditions, fungicide usage is an important step for angular leaf spot management. Since the effects of this method of control on plant physiology are not known, this study had the following objectives: a) Verify the action of fungicide in physiologi...

  8. 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.

  9. Predicting multiple ecotoxicological profiles in agrochemical fungicides: a multi-species chemoinformatic approach.

    Science.gov (United States)

    Speck-Planche, Alejandro; Kleandrova, Valeria V; Luan, Feng; Cordeiro, M Natália D S

    2012-06-01

    Agriculture is needed to deal with crop losses caused by biotic stresses like pests. The use of pesticides has played a vital role, contributing to improve crop production and harvest productivity, providing a better crop quality and supply, and consequently contributing with the improvement of the human health. An important group of these pesticides is fungicides. However, the use of these agrochemical fungicides is an important source of contamination, damaging the ecosystems. Several studies have been realized for the assessment of the toxicity in agrochemical fungicides, but the principal limitation is the use of structurally related compounds against usually one indicator species. In order to overcome this problem, we explore the quantitative structure-toxicity relationships (QSTR) in agrochemical fungicides. Here, we developed the first multi-species (ms) chemoinformatic approach for the prediction multiple ecotoxicological profiles of fungicides against 20 indicators species and their classifications in toxic or nontoxic. The ms-QSTR discriminant model was based on substructural descriptors and a heterogeneous database of compounds. The percentages of correct classification were higher than 90% for both, training and prediction series. Also, substructural alerts responsible for the toxicity/no toxicity in fungicides respect all ecotoxicological profiles, were extracted and analyzed.

  10. Fate and transport of agriculturally applied fungicidal compounds, azoxystrobin and propiconazole.

    Science.gov (United States)

    Edwards, Paul G; Murphy, Tracye M; Lydy, Michael J

    2016-03-01

    Fungicidal active ingredients azoxystrobin and propiconazole, individually and in combination, have been marketed worldwide in a range of fungicide treatment products for preventative and curative purposes, respectively. Their presence in streams located throughout the midwestern and southeastern United States warrant the need for research into the potential routes of transport of these fungicides in an agricultural field setting. Potential canopy penetration and drift effects of these fungicides during aerial and ground applications were studied in the current project. Canopy penetration was observed for both application types, however drift was associated only with the aerial application of these fungicides. Azoxystrobin and propiconazole persisted in the soil up to 301 d, with peak concentrations occurring approximately 30 d after application. The predominant mode of transport for these compounds was agricultural runoff water, with the majority of the fungicidal active ingredients leaving the target area during the first rain event following application. The timing of application in relation to the first rain event significantly affected the amount of loss that occurred, implying application practices should follow manufacturer recommended guidelines.

  11. Exploitation of genomics in fungicide research: current status and future perspectives.

    Science.gov (United States)

    Cools, Hans J; Hammond-Kosack, Kim E

    2013-02-01

    Every year, fungicide use to control plant disease caused by pathogenic fungi increases. The global fungicide market is now worth more than £5.3 billion, second only to the herbicide market in importance. In the UK, over 5500 tonnes of fungicide were applied to crops in 2010 (The Food and Environment Research Agency, Pesticide Usage Statistics), with 95.5% of the wheat-growing area receiving three fungicide sprays. Although dependence on fungicides to produce food securely, reliably and cheaply may be moderated in the future by further developments in crop biotechnology, modern crop protection will continue to require a diversity of solutions, including effective and safe chemical control. Therefore, investment in exploiting the increasingly available genome sequences of the most devastating fungal and oomycete phytopathogenic species should bring an array of new opportunities for chemical intervention. To date, the impact of whole genome research on the development, introduction and stewardship of fungicides has been limited, but ongoing improvements in computational analysis, molecular biology, chemical genetics, genome sequencing and transcriptomics will facilitate the development and registration of the future suite of crop protection chemicals.

  12. 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

  13. New α-Methylene-γ-Butyrolactone Derivatives as Potential Fungicidal Agents: Design, Synthesis and Antifungal Activities

    Directory of Open Access Journals (Sweden)

    Yongling Wu

    2016-01-01

    Full Text Available In consideration of the fact that the α-methylene-γ-butyrolactone moiety is a major bio-functional group in the structure of carabrone and possesses some agricultural biological activity, forty-six new ester and six new ether derivatives containing α-methylene-γ-butyrolactone moieties were synthesized, and their fungicidal activities against Colletotrichum lagenarium and Botrytis cinerea were investigated. Most of the synthesized compounds showed moderate to significant fungicidal activity. Among them, halogen atom-containing derivatives showed better activity than others, especially compounds 6a,d which exhibited excellent fungicidal activity against C. lagenarium, with IC50 values of 7.68 and 8.17 μM. The structure-activity relationship (SAR analysis indicated that ester derivatives with electron-withdrawing groups on the benzene ring showed better fungicidal activity than those with electron-donating groups. A quantitative structure-activity relationship (QSAR model (R2 = 0.9824, F = 203.01, S2 = 0.0083 was obtained through the heuristic method. The built model revealed a strong correlation of fungicidal activity against C. lagenarium with the molecular structures of these compounds. These results are expected to prove helpful in the design and exploration of low toxicity and high efficiency α-methylene-γ-butyrolactone-based fungicides.

  14. Dissociation dynamics of methylal

    Energy Technology Data Exchange (ETDEWEB)

    Beaud, P.; Frey, H.-M.; Gerber, T.; Mischler, B.; Radi, P.P.; Tzannis, A.-P. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The dissociation of methylal is investigated using mass spectrometry, combined with a pyrolytic radical source and femtosecond pump probe experiments. Based on preliminary results two reaction paths of methylal dissociation are proposed and discussed. (author) 4 fig., 3 refs.

  15. Toxicity of three strobilurins (kresoxim-methyl, pyraclostrobin, and trifloxystrobin) on Daphnia magna.

    Science.gov (United States)

    Cui, Feng; Chai, Tingting; Liu, Xiaoxu; Wang, Chengju

    2017-01-01

    Strobilurins constitute a new class of fungicides that is the most widely used in the world. The present study was conducted to investigate the aquatic toxicity of 3 common strobilurin fungicides (kresoxim-methyl, pyraclostrobin, and trifloxystrobin) to Daphnia magna. The neonate acute immobilization test showed that the 48-h 50% effective concentration (EC50) values of kresoxim-methyl, pyraclostrobin, and trifloxystrobin were 443.3 µg/L, 20.9 µg/L, and 23.0 µg/L, respectively. In addition, the 3 strobilurins significantly induced activity of the important detoxification enzyme glutathione S-transferase (GST) in D. magna, and there was a significant positive relationship between GST activity and immobility of D. magna after acute exposure. The 3 strobilurins showed higher toxicity to D. magna embryos, and the 48-h EC50 were 157.3 µg/L, 3.9 µg/L, and 1.7 µg/L for kresoxim-methyl, pyraclostrobin, and trifloxystrobin, respectively. The 21-d chronic test revealed that the strobilurins could also significantly affect the reproduction, development, and growth of D. magna at sublethal concentrations. The lowest-observed-effect concentrations of kresoxim-methyl, pyraclostrobin, and trifloxystrobin for reproduction were 20 µg/L, 0.15 µg/L, and 0.2 µg/L, respectively, which were close to environmental concentrations. The findings indicate that strobilurin fungicides are very toxic to D. magna and they are sufficient to cause harm to D. magna at environmentally relevant concentrations. Environ Toxicol Chem 2017;36:182-189. © 2016 SETAC. © 2016 SETAC.

  16. 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

  17. Effect Study of Different Fungicides on Wheat Powdery Mildew%不同杀菌剂防治小麦白粉病药效研究

    Institute of Scientific and Technical Information of China (English)

    石晓慧; 章诚

    2013-01-01

    研究不同杀菌剂对小麦白粉病的防治效果,结果表明:25%丙环唑乳油、50%醚菌酯水分散粒剂对小麦白粉病的防治效果较好,平均防治效果分别达到84.72%、86.05%。%Effect of different fungicides on wheat powdery mildew was studied.The results showed that 25% propiconazole EC and 50%Kresoxim-methyl WG had better control effects on wheat powdery mildew ,the average control effect reached 84.72%,86.05%,respectively.

  18. 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....

  19. 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.

  20. 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.

  1. Stereoselective degradation of chiral fungicide myclobutanil in rat liver microsomes.

    Science.gov (United States)

    Yan, Jin; Zhang, Ping; Wang, Xinru; Wang, Yao; Zhou, Zhiqiang; Zhu, Wentao

    2014-01-01

    Myclobutanil, (RS)-2-(4-chlorophenyl)-2-(1H-1, 2, 4-triazol-1-ylmethyl)hexanenitrile is a broad-spectrum systemic triazole fungicide which consists of a pair of enantiomers. The stereoselective degradation of myclobutanil was investigated in rat liver microsomes. The concentrations of myclobutanil enantiomers were determined by high-performance liquid chromatography (HPLC) with a cellulose-tris-(3,5-dimethyl-phenylcarbamate)-based chiral stationary phase (CDMPC-CSP) under reversed phase condition. The t(1/2) of (+)-myclobutanil is 8.49 min, while the t(1/2) of (-)-myclobutanil is 96.27 min. Such consequences clearly indicated that the degradation of myclobutanil in rat liver microsomes was stereoselective and the degradation rate of (+)-myclobutanil was much faster than (-)-myclobutanil. In addition, significant differences between two enantiomers were also observed in enzyme kinetic parameters. The V(max) of (+)-myclobutanil was about 4-fold of (-)-myclobutanil and the CL(int) of (+)-myclobutanil was three times as much as (-)-myclobutanil after incubation in rat liver microsomes. Corresponding consequences may shed light on the environmental and ecological risk assessment for myclobutanil and may improve human health.

  2. Environmental behavior of the fungicide metalaxyl in experimental tobacco field.

    Science.gov (United States)

    Triantafyllidis, Vasilios; Hela, Dimitra; Patakioutas, George

    2013-01-01

    The loss of metalaxyl, a systemic fungicide, was determined in runoff water from loamy soil plots of various surface slopes cultivated with tobacco, over a period of 170 days. Conditions were selected to simulate agricultural practices employed in the Mediterranean region. The surface slopes of plots were 0, 2.5, 5, 7.5, 10% and both cultivated and uncultivated (control) areas were simultaneously monitored. The cumulative losses of metalaxyl in surface runoff from tilled and untilled plots with a slope of 10% were estimated at 0.469% and 0.740% of the initial applied active ingredient respectively, while for the plots with a slope 0% they were 0.033% and 0.044%. The dissipation in topsoil was studied for a period of 110 days. The half-lives that were calculated using first-order kinetics ranged from 13.7 to 16.6 days in tobacco soil and from 13.8 to 17 days in non-cropped soil. The dissipation of metalaxyl from the topsoil in cultivation of tobacco was higher in comparison with the untilled plots (46-62% and 52-69% respectively, of the applied dose in 23 days after the second application). The slope of soil surface, the compound solubility and sorption capacities are the main parameters that influenced the transport of metalaxyl residues via surface water in soil-water systems.

  3. EVALUATION OF FUNGICIDAL EFFICIENEY OF IRANIAN MADE BENZALKONIUM CHLORIDE

    Directory of Open Access Journals (Sweden)

    K. Imandel

    1995-12-01

    Full Text Available Fungicidal efficiency of Iranian made benzalkonium chloride named Akhgar, Afshang and Hamoon were evaluated on pure culture species of Aspergillus nijer, Candida ablicans and Mucour according to the standard method No. 2442 issued by the Institute of Standards and Industrial Research of Iran, from October 1993 to March 1994. Suspensions were prepared in a way that each cubic centimeter having 3.5×107 condia of Aspergillus nijer, 4×107 Candida albicans yeast cell and 2×107 Mucour spore, and Improved Neubauer slide counting cell were used for enumeration. These laboratory study showed that Lecithine and Tween were the best neutralizers with equal power. Usage of five dilutions of 0.4, 0.6, 0.8, 1 fungus separately at 6.5 to 6.7 pH, confirmed the correctness of dilution figure of 0.4 percent proposed by producer companies and showed that these fungi are still sensitive against Benzalkonium Chloride disinfectants.

  4. Immunomodulatory effects of the fungicide Mancozeb in agricultural workers.

    Science.gov (United States)

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

    2005-10-15

    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-alpha 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.

  5. Does farm fungicide use induce azole resistance in Aspergillus fumigatus?

    Science.gov (United States)

    Kano, Rui; Kohata, Erina; Tateishi, Akira; Murayama, Somay Yamagata; Hirose, Dai; Shibata, Yasuko; Kosuge, Yasuhiro; Inoue, Hiroaki; Kamata, Hiroshi; Hasegawa, Atsuhiko

    2015-02-01

    Azole resistance of Aspergillus fumigatus isolates has been reported worldwide and it would appear to be mainly due to a point mutation in the 14α-sterol demethylase (CYP51A) gene, which is the target enzyme for azoles. The mutation has been confirmed in isolates from patients who received long-term itraconazole (ITZ) therapy and from agricultural fields where high levels of azole fungicides were employed. However, the relationship between farm environments and azole-resistant A. fumigatus has not been fully studied. In this investigation, 50 isolates of A. fumigatus were obtained from a farm where tetraconazole has been sprayed twice a year for more than 15 years. The mean minimum inhibitory concentration (MIC) of isolates was 0.74 (0.19-1.5) mg/L against ITZ, which was below the medical resistance level of ITZ. The sequence of CYP51A from isolates indicated no gene mutations in isolates from the farm. Antifungal susceptibility of isolates to tetraconazole showed that spraying with tetraconazole did not induce resistance to tetraconazole or ITZ in A. fumigatus.

  6. 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.

  7. Interactions among cooling, fungicide and postharvest ripening temperature on peaches

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Trujillo, J. Pablo; Cano, Antonio; Artes, Francisco [Postharvest and refrigeration Lab., Dept. of Food Science and Technology, CEBAS-CSIC, Murcia (Spain)

    2000-07-01

    Peach fruit (Prunus persica L. cv. 'Miraflores') harvested at the firm-ripe stage, treated or not with 2 g l{sup -1} iprodione, were cooled or not at 1{sup o}C and ripened at 15 or 20{sup o}C and 95% RH for 10 days. During ripening, weight loss, fungal development and changes in quality parameters (firmness, soluble solids content, titratable acidity, pH and ground and flesh color), and carbon dioxide and ethylene production were monitored. Cooling alone or combined with iprodione avoided Rhizopus nigricans decay during ripening at either ripening temperatures. A skin damage not previously reported on fungicide treated peach was observed at 20{sup o}C. Cooled fruit ripened at 15{sup o}C showed an anomalous respiration rate and ethylene production after the climacteric peak, a loss of firmness and a drop in titratable acidity after 7 days of storage, and reduced endo-polygalacturonase activity in presence of continuous pectinmethylesterase activity during the first week. Cooling before ripening at 20{sup o}C led to the best flavor without excessive total losses. These results helped in the optimization of warming cycles during cold storage used to avoid chilling injuries development on peaches. (Author)

  8. Sensitivity of four Yeasts to Fungicides and CO2 Concentrations and Their Antagonistic Ability in Combination with Fungicide to pathogenic Fungi in vitro

    Institute of Scientific and Technical Information of China (English)

    TIAN Shi-ping; YAO Hong-jie; QIN Guo-zheng; XU Yong; FENG Xiao-yuan

    2004-01-01

    The yeasts Cryptococcus laurentii,Trichosporon pullulans,Rhodotorula glutinis and Trichosporon sp.were used to investigate their sensitivity to four fungicides and different concentrations of CO2,as well as their antagonistic ability to Penicilliumexpansum and Alternaria alternata in vitro when applied with fungicide.There were significant differences in sensitivity to the fungicides among the different yeasts(P = 0.05).R.glutinis was more sensitive to Deccocil,Iprodione and Stroby as compared to other yeasts.Combination antagonistic yeasts with fungicide could more significantly enhance biocontrol ability of the yeasts against the pathogenic fungi in vitro(P = 0.05).C.laurentii was the most effective antagonist among the four yeasts and could completely control spore germination of P.expansum and A.alternata when combined with Stroby at the concentration of 100 μL L-1.The yeasts,except R.glutinis,could grow well on nutrient yeast dextrose agar (NYDA) after 8 d incubation even at 20% CO2 concentration at 25℃.Particularly Trichosporon sp.showeda better adaptability to low temperature as compared to other antagonists.

  9. Enrichment of methylated DNA by methyl-CpG immunoprecipitation.

    Science.gov (United States)

    Sonnet, Miriam; Baer, Constance; Rehli, Michael; Weichenhan, Dieter; Plass, Christoph

    2013-01-01

    Normal DNA methylation is an epigenetic modification required for proper development. Aberrant DNA methylation, in contrast, is frequently observed in many different malignancies including leukemias and lymphomas. Global DNA methylation profiling addresses the methylated sequences (methylome) of patient genomes to identify disease-specific methylation patterns. Workload in methylome analyses can be considerably reduced by methylome enrichment using proteins or antibodies with high affinity to methylated DNA. Methyl-CpG Immunoprecipitation (MCIp) employs an immobilized recombinant human methyl-CpG binding domain protein 2, MBD2, which binds methylated CpGs in double-stranded DNA. Elution with increasing salt concentrations allows the fractionated enrichment of different degrees of methylation.

  10. Determination of Nine Fungicides in Grape and Wine Using QuEChERS Extraction and LC/MS/MS Analysis.

    Science.gov (United States)

    Martínez, Gracia; Morales, Ascensión; Maestro, Alba; Cermeño, Sandra; Oliva, José; Barba, Alberto

    2015-01-01

    An analytic procedure was developed for the determination of the fungicides ametoctradin, boscalid, cyazofamid, dimethomorph, fenhexamid, kresoxim-methyl, mepanipyrim, metrafenone, and pyraclostrobin in grape and wine. A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) procedure was used for the extraction. Analysis of the extract was performed by LC/triple quadrupole-MS/MS. A Poroshell 120 EC-C18 column was used with a programmed gradient mobile phase consisting of (A) acetonitrile containing 0.1% formic acid and (B) water containing 0.1% formic acid and 2 mM ammonium formate. The acceptance criteria for the method were those proposed in the SANCO guide. The method was linear for the range of concentration studied (5-100 μg/L), and R2 values were higher than 0.998 and RSD values below 18%. Recovery was over 73.2% in grape and 76.7% in wines, and there was no case of more than 100% recovery. The recovery RSDs in reproducibility conditions were below 17.13% in grape and 15.6% in wines.

  11. Fungal pathogens of the genus Fusarium in winter wheat Triticum aestivum L. protected with fungicides in north-eastern Poland

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    Agnieszka Pszczółkowska

    2013-07-01

    Full Text Available Various diagnostic methods were used to evaluate the effect of fungicide protection on the prevalence of pathogenic fungi in wheat grain. Winter wheat cv. Nutka and Zyta was grown during a field experiment established in the Production and Experimental Station in Bałcyny in 2006–2007. The experimental factor was chemical crop protection: epoxiconazole, kresoxim-methyl and fenpropimorph applied at growth stages BBCH 33–35 as well as dimoxystrobin and epoxiconazole applied at BBCH 51–53. In this experiment, microscopic observations and conventional PCR assays were used as complementary methods. The quantification of Fusarium poae DNA by qPCR demonstrated the effectiveness of chemical protection against the analyzed fungal species. Lower monthly precipitation levels and higher daily temperatures intensified grain infections, in particular those caused by F. poae. A significant correlation was determined between the number of F. poae cultures isolated from winter wheat grain and the quantity of pathogenic DNA in grain identified by qPCR. Grain infections caused by F. poae lowered yield and thousand seed weight.

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

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    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

  13. Sterol-inhibiting fungicide impacts on soil microbial ecology in Atlantic Coastal Plain soils

    Science.gov (United States)

    White, P. M.; Potter, T. L.; Strickland, T. C.

    2008-12-01

    Seventy-five percent of the peanuts (Arachus hypogaia) produced in the United States are grown in the Atlantic Coastal Plain region. Portions of this area, including Alabama and Georgia, exhibit a subtropical climate that promotes soil-borne plant fungal diseases. Most fields receive repeated fungicide applications during the growing season to suppress the disease causing organisms, such as Sclerotium rolfsii, Rhizoctonia solani, and Cylindrocladium parasiticum. Information regarding fungicide effects on the soil microbial community, with components principally responsible for transformation and fate of fungicides and other soil-applied pesticides, is limited. The objectives of the study were to assess soil microbial community response to (1) varying rates of the sterol-inhibiting fungicide tebuconazole (0, single application, season max, 2x season max), and (2) field rates of the sterol-inhibitors cyproconazole, prothioconazole, tebuconazole, and flutriafol, and thiol-competitor chlorothalonil. The sterol-inhibitors exhibited different half lives, as listed in the FOOTPRINT database, ranging from 1300 d. Chlorothalonil was chosen because it is the most frequently applied fungicide to peanut. Shifts in the fungi, gram positive and gram negative bacteria, were monitored during the experiments using phospholipid fatty acid (PLFA) profiles. Ergosterol levels and pesticide decay rates were also monitored to evaluate the effectiveness of the fungicide and soil residence time, respectively. In the rate study, the highest rate of tebuconazole reduced the fungal biomarker 18:2ω6,9c to 2.6 nmol g-1 dry soil at 17 d, as compared to the control (4.1 nmol g-1 dry soil). However, levels of the fungal PLFA biomarker were similar regardless of rate at 0 and 32 d. The gram negative bacterial PLFA mole percent was greater at 17 d for the two highest rates of tebuconazole, but was similar at 0 and 32 d. Gram positive and fungal mole percents were not affected at any time point

  14. Control of Fusarium head blight of winter wheat by artificial and natural infection using new fungicides

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    Olga Treikale

    2012-12-01

    Full Text Available In Latvia, climatic factors are influential in spreading of Fusarium head blight of cereals caused by Fusarium species. The most significant factor affecting the incidence of the disease in winter wheat is hightened temperature at the time of wheat anthesis. Field trials for the control of the disease in winter wheat were done in 2003-2004 using new fungicides applied at various rates by natural infection and artificial inoculation. Three species of causative agents: Fusarium avenaceum var. herbarum, F. gibbosum, F. culmorum were collected from infected seeds of wheat and used for inoculation of experimental plots at the concentration 106 conidia ml-1 (1:1:1 at the stage of full anthesis. Effective control of the disease was obtained through application of new fungicides with different active ingredient: Prosaro 250 EC (tebuconazole 125 G, prothioconazole 125 G L-1, Input 460 EC (spiroxamine 300 G, prothioconazole 160 G L-1. In conditions of artificial infection by severe attack of Fusarium spp. the application of fungicides containing tebuconazole at T3 gave significant influence on yield of winter wheat through plumpness of grains increase. High efficacy of fungicides against leaf infection with Erysiphe graminis and Drechslera tritici-repentis was also in the trial achieved. Application of fungicide containing cyproconazole and trifloxystrobin at T1 in the trial 2004 gave good control of Septoria tritici, E. graminis and D. triticirepentis.

  15. Synthesis and fungicidal activity of aryl carbamic acid-5-aryl-2-furanmethyl ester.

    Science.gov (United States)

    Li, Ying; Li, Bao-Ju; Ling, Yun; Miao, Hong-Jian; Shi, Yan-Xia; Yang, Xin-Ling

    2010-03-10

    Chitin, a major structural component of insect cuticle and fungus cell wall but absent in plants and vertebrates, is regarded as a safe and selective target for pest control agents. Chitin synthesis inhibitors (CSIs) have been well-known as insect growth regulators (IGRs) but rarely found as fungicides in agriculture. To find novel CSIs with good activity, benzoylphenylurea, a typical kind of CSIs, was chosen as the lead compound and 26 novel aryl carbamic acid-5-aryl-2-furanmethyl esters were designed by converting the urea linkages of benzoylphenylureas to carbamic acid esters and changing the aniline parts into furanmethyl groups. The title compounds were synthesized and their structures confirmed by IR, (1)H NMR, and elemental analysis. Preliminary insecticidal and fungicidal bioassays were carried out. The results indicated that the title compounds had no insecticidal effect on Culex pipiens pallens and Plutella xylostella Linnaeus , but most compounds exhibited good fungicidal activities against Corynespora cassiicola , Thanatephorus cucumeris , Botrytis cinerea , and Fusarium oxysporum . In particular, compounds V-4, V-6, V-7, and V-8 showed better activities against the four strains than those of the commercialized fungicides. The morphologic result suggested that compound V-21 had disturbed the cell wall formation of C. cassiicola. The results indicated that modification on the urea linkage of benzoylphenylurea was an effective way to discover new candidates for fungicides.

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

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    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.

  17. Fungicide residues in grapes determined the dynamics of Saccharomyces cerevisiae strains during spontaneous wine fermentation

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    Čuš Franc

    2011-01-01

    Full Text Available Impact of three fungicides against B. cinerea (iprodione, pyrimethanil and f ludioxonil plus cyprodinil on the population of Saccharomyces cerevisiae strains during the spontaneous alcoholic fermentation was studied. With regard to the use of fungicides in the vineyard at two stages of the grapevine growth we followed four different spontaneous fermentations: control, iprodione, pyrimethanil and f ludioxonil plus cyprodinil. The fungicide residues in the grapes were determined by GC/MS system and the fermentations were followed by changes in yeast, sugar, and ethanol concentrations using colony counting and HPLC. The karyotype analysis of 473 isolates was done by pulsed-field gel electrophoresis. The fungicide residues in the grapes at the harvest were below the maximum residue limits. Isolates of S. cerevisiae were classified into 15 karyotype groups. The duration of the processes and the populations of the karyotypes differed between the fermentations. The iprodione and control fermentations lasted 36 days with the prevalence of karyotype A while the fludioxonil plus cyprodinil fermentation lasted 50 days and karyotype D led the process. In the pyrimethanil fermentation, none of the karyotypes prevailed in the must and the fermentation lasted much longer than others did (68 days. The results showed that the fungicide residues have an influence on the fermentation kinetics and selection of S. cerevisiae strains during the spontaneous alcoholic fermentation and therefore should be considered as an important factor that may indirectly influence the formation of fermentation aroma in the wine produced by such process.

  18. Synthesis and anti-fungicidal activity of some transition metal complexes with benzimidazole dithiocarbamate ligand

    Science.gov (United States)

    Mohamed, Gehad G.; Ibrahim, Nasser A.; Attia, Hanaa A. E.

    2009-04-01

    Seven transition metal complexes of benzimidazole ligand (HL) are reported and characterized based on elemental analyses, IR, solid reflectance, magnetic moment, molar conductance and thermal analyses (TGA and DTA). From the obtained data, the complexes were proposed to have the general formulae [MX 2(HL)(H 2O)]· yH 2O, where M = Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cr(III); X = Cl -, SO 42- and y = 0-4. The molar conductance data revealed that all the metal chelates were non-electrolytes. From the magnetic and solid reflectance spectra, it was found that the geometrical structure of these complexes is octahedral. The thermal behaviour of these chelates showed that the hydrated complexes loss water molecules of hydration in the first step followed immediately by decomposition of the anions and ligand molecules in the subsequent steps. Fungicidal activity of the prepared complexes and free ligand was evaluated against three soil borne fungi. Data obtained showed the higher biological activity of the prepared complexes than the parent Schiff base ligand. Formulation of the most potent complex was carried out in the form of 25% WP. Fungicidal activity of the new formulation was evaluated and compared with the standard fungicide Pencycuron (Monceren 25% WP). In most cases, the new formulation possessed higher fungicidal activity than the standard fungicide under the laboratory conditions.

  19. 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

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

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    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.

  1. Fungicide baseline for mycelial sensitivity of Exserohilum turcicum, causal agent of northern corn leaf blight

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    Roberto Luis De Rossi

    2015-03-01

    Full Text Available Northern corn leaf blight, caused by Exserohilum turcicum (Et, is one of the major corn diseases which can reduce grain yield and quality. The aim of this study was to determine the mycelial sensitivity of ten Et isolates, five from Argentina and five from Brazil, to six fungicides (carbendazim, captan, fludioxinil, metalaxyl, iprodione and thiram used in seed treatment. The inhibitory concentration (IC50 was determined by using seven concentrations of the fungicides supplemented to the agar medium. The mycelial colony diameter was measured with a digital caliper. Experimental design was completely randomized with four replicates. Data on the percent mycelial growth inhibition were analyzed by logarithmic regression and the IC50 was calculated. The fungicide iprodione was the most potent, with IC50 50 mg/L for all isolates. Although iprodione is the most potent fungicide, it is not used for corn seed treatment. The IC50s obtained in this study can be used as baseline for future monitoring studies of Et sensitivity to fungicides.

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

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    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.

  3. Biochemical and Genetic Responses of Fungi to the Toxic Effect of Synthetic and Natural Fungicides

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    Maria-Elena Baez-Flores

    2008-01-01

    Full Text Available The objective of the present review is to analyze the molecular basis of fungicide resistance mechanism to both synthetic fungicides and the natural fungicides isothiocyanates. The review is focused mainly on Alternaria sp., but whenever available, similar studies in other fungi have been included. Fungal resistant strains to dicarboximide and phenylpyrrole fungicides have been found to contain mutations in one of the proteins involved in the signal transduction pathway that regulates the fungal response to osmotic stress. By the other hand, it was found that isothiocyanates induce enzymes like glutathione S-transferase, cyanide hydratase, heat shock proteins, membrane transporters and proteins associated with the oxidative stress response. Also, inter simple sequence repeats polymorphism was recorded as a response to the isothiocyanates treatment. The knowledge about the genetic basis of the response mechanism of Alternaria sp. to the isothiocyanates is scarce. Therefore, studies by DNA recombinant technology to analyze the fungi responses to fungicides, will allow knowing the metabolic pathways involved in the phenomena to permit the design of strategies to inhibit key reactions involved in the fungal resistance, reaching a better and sustainable fungal infections control.

  4. 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 (Pfungicide-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.

  5. Resistance Mechanisms and Molecular Docking Studies of Four Novel QoI Fungicides in Peronophythora litchii.

    Science.gov (United States)

    Zhou, Yuxin; Chen, Lei; Hu, Jian; Duan, Hongxia; Lin, Dong; Liu, Pengfei; Meng, Qingxiao; Li, Bin; Si, Naiguo; Liu, Changling; Liu, Xili

    2015-12-14

    Peronophythora litchii is the causal agent of litchi downy blight. Enestroburin, SYP-1620, SYP-2815 and ZJ0712 are four novel QoI fungicides developed by China. Eight mutants of P. litchii resistant to these QoI fungicides and azoxystrobin (as a known QoI fungicide) were obtained in our preliminary work. In this study, the full length of the cytochrome b gene in P. litchii, which has a full length of 382 amino acids, was cloned from both sensitive isolates and resistant mutants, and single-site mutations G142A, G142S, Y131C, or F128S were found in resistant mutants. Molecular docking was used to predict how the mutations alter the binding of the five QoI fungicides to the Qo-binding pockets. The results have increased our understanding of QoI fungicide-resistance mechanisms and may help in the development of more potent inhibitors against plant diseases in the fields.

  6. APPLICATION OF FOLIAR FERTILIZER AND FUNGICIDES ON WHITE SPOT DISEASE CONTROL AND DEVELOPMENT OF MAIZE

    Directory of Open Access Journals (Sweden)

    C. H. Brito

    2016-11-01

    Full Text Available This study aimed to evaluate the effect of forms of application of foliar fertilizers and fungicides to control fungus causing white maize spot, Phaeosphaeria maydis, and the growth and development of hybrids maize. The design had randomized blocks, with the use two sources hybrids maize with different reaction to white maize spot: resistant and susceptive and application with moisture of foliar chemical fungicide + cobalt foliar + molybdenum foliar + manganese and control treatment, without application consisting of four treatments and five replications. In the treatments with application of moisture were done on vegetative maize growth stage V8 (stage that determine that the number of kernel rows, VT (stage that arrives when the last branch of the tassel is completely visible and reproductive maize growth stage R2 (kernels are white on the outside and resemble a blister. The evaluation of variables of growth of maize plants: grain dry mass, cob dry mass, leaf dry mass, culm dry mass and modificated leaf ear and total plant dry mass. Harvest was carried out when the grains were 20% humidity. The application of fungicides and foliar fertilizers increased the leaves, culm, ear modificated, cobs and shoot dry mass plants maize. The application of fungicides and foliar fertilizers providing returning of 11.409,5 kg ha-1 of shoot dry mass plants with increased of 1.296 kg ha-1 on soil(12,81%. In the susceptive hybrid maize the application of fungicides and foliar fertilizers provide higher dry mass grains and shoot of plants.

  7. Identification of Metabolites of the Fungicide Penconazole in Human Urine.

    Science.gov (United States)

    Mercadante, R; Polledri, E; Scurati, S; Moretto, A; Fustinoni, S

    2016-07-18

    Penconazole (PEN) is a fungicide used in agriculture that has been classified as hazardous to humans and the environment. The objective of this work was to identify PEN urinary metabolites in humans and propose a biomarker for PEN exposure. Five urine samples were collected from agricultural workers who worked with and were exposed to PEN. Samples were analyzed by liquid chromatography coupled with hybrid triple quadrupole-linear ion trap mass spectrometry, with the source operating in the electrospray ionization mode. Metabolites previously identified in animal studies were searched as possible metabolites in humans. Candidate metabolites were first identified by multiple reaction monitoring following the protonated molecular ions that generated the protonated triazole moiety, which is expected to be present in all PEN metabolites; second, the isotopic patterns of the molecular ions were checked for consistency with the presence of two chlorine atoms; third, the full mass spectra were evaluated for consistency with the molecular structure. Seven different oxidized metabolites were found, both in the free and glucuronide conjugate forms. The major metabolite was the monohydroxyl-derivative PEN-OH (median molar fraction approximately 0.92 as a sum of free and glucuronide conjugated form). The product of further oxidation was the carboxyl-derivate PEN-COOH (median molar fraction approximately 0.03). After hydrolysis with β-glucuronidase, the free compounds were quantified in the presence of deuterated PEN as an internal standard; PEN-OH levels ranged from 230 to 460 μg/L, and PEN-COOH levels ranged from 5.2 to 16.7 μg/L. We propose a pathway for PEN metabolism in humans and suggest PEN-OH, after hydrolysis of glucuronide conjugates, as a biomarker for monitoring human exposure to PEN.

  8. TENACITY AND PERSISTENCE OF COPPER FUNGICIDES IN CITRUS SEEDLINGS UNDER SIMULATED RAINFALL

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    ANTONIO EDUARDO FONSECA

    2016-01-01

    Full Text Available The amount of fungicide that adheres to the leaf during spraying and the amount that remain on the leaf after weathering are the main factors that defines the amount of active residue on the leaf surface to effectively control plant pathogens. Thus, the objective of this work was to evaluate the tenacity and persistence of copper in citrus seedling leaves under simulated rainfall in Jaboticabal, State of São Paulo, Brazil. The evaluated variables were copper content, solution retention, surface tension and drop spectrum. A significant and inversely proportional linear relationship to drops <100 μm was found. The percentage of copper retained in leaves of citrus seedlings with copper fungicides of suspension concentrate (SC formulations after simulated rainfall was greater than 80%. Copper fungicides of SC formulations presented the lowest surface tension, allowing greater tenacity and persistence of copper on seedlings of citrus leaves after simulated rainfall and increased contact between the drops and leaf surface.

  9. Contamination of vineyard soils with fungicides: a review of environmental and toxicological aspects.

    Science.gov (United States)

    Komárek, Michael; Cadková, Eva; Chrastný, Vladislav; Bordas, François; Bollinger, Jean-Claude

    2010-01-01

    The contamination of agricultural soils with inorganic (Cu-based) and organic pesticides (including their residues) presents a major environmental and toxicological concern. This review summarizes available studies published on the contamination of vineyard soils throughout the world with Cu-based and synthetic organic fungicides. It focuses on the behavior of these contaminants in vineyard soils and the associated environmental and toxicological risks. The concentrations of Cu in soils exceed the legislative limits valid in the EU in the vast majority of the studied vineyards. Regarding the environmental and toxicological hazards associated with the extensive use of fungicides, the choice of fungicides should be performed carefully according to the physico-chemical properties of the soils and climatic and hydrogeological characteristics of the vine-growing regions.

  10. Ranking of fungicides according to risk assessments for health and environment

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Ørum, Jens Erik

    2014-01-01

    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 practic...... system it is expected that the system could lead to more problems related to pesticide resistance.......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...... 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...

  11. Field screening method for above-tolerance residues of dithiocarbamate fungicides.

    Science.gov (United States)

    Ott, D E; Gunther, F A

    1982-07-01

    A field screening method has been developed for detecting above-tolerance residues of dithiocarbamate (DTC) fungicides on fruits and vegetables. A harvested crop might be condemned as unfit for market if above-tolerance DTC residues are present; however, by using this screening method, a grower might be able to postpone harvesting a crop until the screening test indicates that residues have dissipated below the tolerance level. The method depends on carbon disulfide generated from DTC fungicides at an elevated temperature into the headspace gas above the contents of a septum-sealed reaction flask, with hydrochloric acid and stannous chloride present. The syringe-withdrawn, headspace carbon disulfide then reacts with the appropriate chromophore reagent already in the syringe. The lower limit of detectability is about 2 ppm DTC fungicide from 30 g chopped crop. A single test can be completed in about 90 min; the average time per test when several are conducted sequentially is considerably shorter.

  12. Predictive value of cell assays for developmental toxicity and embryotoxicity of conazole fungicides.

    Science.gov (United States)

    Dreisig, Karin; Taxvig, Camilla; Birkhøj Kjærstad, Mia; Nellemann, Christine; Hass, Ulla; Vinggaard, Anne Marie

    2013-01-01

    This paper evaluates in vivo predictability of a battery of in vitro tests covering developmental toxicity and embryotoxicity of five widely used conazole fungicides. The conazoles were investigated in the embryonic stem cell test, and data were compared to in vivo embryotoxicity data. The same conazoles were evaluated on the basis of data from a battery of cell assays for endocrine activity, including assays for AR, ER, AhR, and sex hormone synthesis, and data were compared to in vivo developmental toxicity data. Overall, the ranking of the five conazole fungicides based on in vitro data were 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 was possible by a holistic evaluation of data from a panel of cell-based assays.

  13. [DNA methylation and epigenetics].

    Science.gov (United States)

    Vaniushin, B F

    2006-09-01

    In eukaryotic cells, nuclear DNA is subject to enzymatic methylation with the formation of 5-methylcytosine residues, mostly within the CG and CNG sequences. In plants and animals this DNA methylation is species-, tissue-, and organelle-specific. It changes (decreases) with age and is regulated by hormones. On the other hand, genome methylation can control hormonal signal. Replicative and post-replicative DNA methylation types are distinguished. They are mediated by multiple DNA methyltransferases with different site-specificity. Replication is accompanied by the appearance of hemimethylated DNA sites. Pronounced asymmetry of the DNA strand methylation disappears to the end of the cell cycle. A model of methylation-regulated DNA replication is proposed. DNA methylation controls all genetic processes in the cell (replication, transcription, DNA repair, recombination, and gene transposition). It is the mechanism of cell differentiation, gene discrimination and silencing. In animals, suppression of DNA methylation stops development (embryogenesis), switches on apoptosis, and is usually lethal. Disruption of DNA methylation pattern results in the malignant cell transformation and serves as one of the early diagnostic features of carcinogenesis. In malignant cell the pattern of DNA methylation, as well as the set of DNA methyltransferase activities, differs from that in normal cell. In plants inhibition of DNA methylation is accompanied by the induction of seed storage and florescence genes. In eukaryotes one and the same gene can be simultaneously methylated both at cytosine and adenine residues. It can be thus suggested, that the plant cell contains at least two different, and probably, interdependent systems of DNA methylation. The first eukaryotic adenine DNA methyltransferase was isolated from plants. This enzyme methylates DNA with the formation of N6-methyladenine residues in the sequence TGATCA (TGATCA-->TGm6ATCA). Plants possess AdoMet-dependent endonucleases

  14. 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 ...

  15. QSAR model toward the rational design of new agrochemical fungicides with a defined resistance risk using substructural descriptors.

    Science.gov (United States)

    Speck-Planche, Alejandro; Kleandrova, Valeria V; Rojas-Vargas, Julio A

    2011-11-01

    The increasing resistance of several phytopathogenic fungal species to the existing agrochemical fungicides has alarmed to the worldwide scientific community. There is no available methodology to predict in an efficient way if a new fungicide will have resistance risk due to fungal species which cause considerable crop losses. In an attempt to overcome this problem, a multi-resistance risk QSAR model, based on substructural descriptors was developed from a heterogeneous database of compounds. The purpose of this model is the classification, design, and prediction of agrochemical fungicides according to resistance risk categories. The QSAR model classified correctly 85.11% of the fungicides and the 85.07% of the inactive compounds in the training series, for an accuracy of 85.08%. In the prediction series, the percentages of correct classification were 85.71 and 86.55% for fungicides and inactive compounds, respectively, with an accuracy of 86.39%. Some fragments were extracted and their quantitative contributions to the fungicidal activity were calculated taking into consideration the different resistance risk categories for agrochemical fungicides. In the same way, some fragments present in molecules with fungicidal activity and with negative contributions were analyzed like structural alerts responsible of resistance risk.

  16. Baseline sensitivity to fluopyram and fungicide resistance phenotypes of botrytis cinerea populations from table grapes in california

    Science.gov (United States)

    Gray mold caused by Botrytis cinerea is a major postharvest disease of table grapes grown in the Central Valley of California. Understanding fungicide-resistant phenotypes of B. cinerea is important to the development of pre-harvest fungicide programs for control of postharvest gray mold. Baseline s...

  17. 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.

  18. 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 acrylamide formation, which ranged from 134 to 992 μg kg(-1). There was a significant (p acrylamide formation. Both free asparagine concentration and acrylamide formation increased in response to a lack of 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.

  19. 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.

  20. Fungicide leaching from golf greens: effects of root zone composition and surfactant use.

    Science.gov (United States)

    Larsbo, Mats; Aamlid, Trygve S; Persson, Lave; Jarvis, Nick

    2008-01-01

    Soil water repellency in golf putting greens may induce preferential "finger flow," leading to enhanced leaching of surface applied fungicides. We examined the effects of root zone composition, treatment with a non-ionic surfactant, and the use of the fungicide iprodion or a combination of azoxystrobin and propiconazole on soil water repellency, soil water content distributions, fungicide leaching, and turf quality during 1 yr. Soil water repellency was measured using the water drop penetration time (WDPT) test and tension infiltrometers. Our study was made on a 3-yr-old experimental green seeded with creeping bentgrass (Agrostis stolonifera L.) 'Penn A-4' at Landvik in southeast Norway. The facility consists of 16 lysimeters with two different root zone materials: (i) straight sand (1% gravel, 96% sand, 3% silt and clay, 4 g kg(-1) organic matter) (SS) and (ii) straight sand mixed with garden compost to an organic matter content of 21 g kg(-1) (Green Mix [GM]). Surfactant treatment resulted in 96% lower average WDPTs at 1 cm depth, three times higher water infiltration rates at the soil surface, and reduced spatial variation in soil water contents. Fungicide leaching was close to zero for the GM lysimeters probably due to stronger sorption. Concentrations in the drainage water from SS lysimeters often exceeded surface water guideline values for all three fungicides, but surfactant treatment dramatically reduced fungicide leaching from these lysimeters. In autumn and winter, surfactant-treated plots were more infected with fungal diseases probably because of higher water content in the turfgrass thatch layer.

  1. The effect of foliar fungicides on the mycoflora of seeds of Triticum aestivum

    Directory of Open Access Journals (Sweden)

    Janusz Błaszkowski

    2014-08-01

    Full Text Available The effect of three foliar fungicides. i.e., Bayloton 25 WP, Dithane M-45, and Funaben K. on the mycoflora associated with the seeds of spring Triticum aestivum cv. Kolibri cultivated in the field was investigated. The fungicide which highly reduced the number of both fungal colonies and species was Funaben K. Of the fungi most frequently occurring. Only Funaben K applied on the seeds reduced the proportion of seeds with Alternaria alternata, Cladosporium spp.. and Septoria nodorum. In contrast. seeds from plants traeted with Funaben K harboured significantly more colonies of non-sporulating fungi.

  2. Ranking of fungicides according to risk assessments for health and environment

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Ørum, Jens Erik

    2014-01-01

    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...... 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...

  3. Ranking of fungicides according to risk assessments for health and environment

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Ørum, Jens Erik

    2014-01-01

    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...... 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...

  4. Synthesis and fungicidal activity of tubulin polymerisation promoters. Part 3: imidazoles.

    Science.gov (United States)

    Lamberth, Clemens; Dumeunier, Raphael; Trah, Stephan; Wendeborn, Sebastian; Godwin, Jeremy; Schneiter, Peter; Corran, Andy

    2013-01-01

    A novel class of experimental fungicides has been discovered, which consists of special tetrasubstituted imidazoles. They are highly active against important phytopathogens, such as Botrytis cinerea (grey mould), Uncinula necator (grape powdery mildew), Mycosphaerella graminicola (wheat leaf blotch) and Alternaria solani (potato and tomato early blight). Their fungicidal efficacy is due to their ability to promote fungal tubulin polymerization, which leads to a disruption of microtubule dynamics. These imidazoles are five-membered ring analogs of similar substituted triazolopyrimidines and pyridazines with the same mode of action. A concise four-step synthesis route has been used to prepare them from commercially available starting materials. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Comparative analysis of rubber seed methyl ester with other methyl ...

    African Journals Online (AJOL)

    Comparative analysis of rubber seed methyl ester with other methyl esters. ... In order to achieve a two-step transesterification process was developed to convert rubber seed oil to its methyl esters. The first step, acid catalyzed ... Article Metrics.

  6. 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 pHKCl 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.

  7. Effect of dose rate and mixtures of fungicides on selection for QoI resistance in populations of Plasmopara viticola.

    Science.gov (United States)

    Genet, Jean-Luc; Jaworska, Grazyna; Deparis, Francine

    2006-02-01

    Resistance to QoI fungicides (strobilurins, famoxadone and fenamidone) in populations of Plasmopara viticola (Berk & Curt) Berlese & de Toni developed soon after their introduction in France and Italy. Current resistance management strategies include limitation of the number of applications, use of mixtures and alternation of fungicides with different modes of action. The selection pressure resulting from QoI fungicides applied alone or in mixtures with non-QoI fungicides was investigated in whole plant experiments under controlled conditions. QoI-resistant populations of P. viticola gradually reverted to full sensitivity following consecutive transfers to untreated plants, suggesting that resistant phenotypes were less competitive than sensitive ones. When cycled on QoI-treated plants, reduction in sensitivity was greater for the QoI fungicide which had greater intrinsic activity on P. viticola. Sensitivity decreased at each subsequent cycle, resulting in almost full resistance after four generations. Mixture experiments indicated that selection pressure was affected most by the dose of the QoI fungicide and the nature of the partner fungicide. Folpet delayed selection pressure most effectively when it was associated with famoxadone or azoxystrobin. Mancozeb was least effective at reducing the rate of selection compared with the QoI alone, and fosetyl-aluminium was intermediate. Higher rates of selection were recorded when the dose of the QoI fungicide, solo or in a mixture, was increased from 1 to 4 microg ml(-1). Increasing the dose of the non-QoI partner fungicide in the mixture from 10 to 30 microg ml(-1) resulted in reduced selection pressure. These results suggest that the choice of the fungicide partner and its dosage in the mixture can significantly affect the success of QoI resistance management strategies under practical conditions.

  8. Control of anthracnose disease via increased activity of defence related enzymes in 'Hass' avocado fruit treated with methyl jasmonate and methyl salicylate.

    Science.gov (United States)

    Glowacz, Marcin; Roets, Nico; Sivakumar, Dharini

    2017-11-01

    Development of anthracnose disease caused by Colletotrichum gloeosporioides Penz. is one of the major issues within the avocado supply chain. Exposure to methyl jasmonate (MeJA) and methyl salicylate (MeSA) vapours at 10 and 100µmoll(-1) was investigated as an alternative solution to commercial fungicide - prochloraz® that is currently being used by the industry. The incidence of anthracnose disease was found to be significantly reduced in 'Hass' avocado fruit treated with MeJA or MeSA vapours, especially at 100μmoll(-1). The mechanism involved enhanced activity of defence related enzymes, i.e. chitinase, β-1,3-glucanase and PAL, and higher content of epicatechin. Copyright © 2017. Published by Elsevier Ltd.

  9. Testing of Eight Medicinal Plant Extracts in Combination with Kresoxim-Methyl for Integrated Control of Botrytis cinerea in Apples

    Directory of Open Access Journals (Sweden)

    Burtram C. Fielding

    2015-07-01

    Full Text Available Botrytis cinerea is a fungus that causes gray mold on many fruit crops. Despite the availability of a large number of botryticides, the chemical control of gray mold has been hindered by the emergence of resistant strains. In this paper, tests were done to determine the botryticidal efficacy of selected plant extracts alone or combined with kresoxim-methyl. In total, eight South African medicinal plants viz Artemisia afra, Elyptropappus rhinocerotis, Galenia africana, Hypoxis hemerocallidea, Siphonochilus aetheopicus, Sutherlandia frutescens, Tulbaghia violacea and Tulbaghia alliacea were screened. Allium sativum, a plant species known to have antifungal activity, was included in the in vivo studies. For the in vitro studies, synergistic interactions between the plant extracts and the kresoxim-methyl fungicide were tested with radial growth assays. Data indicated synergistic inhibitory effects between the fungicide and the plant extracts. Next, different doses of plant extracts combined with kresoxim-methyl were used for decay inhibition studies on Granny Smith apples. Synergistic and additive effects were observed for many of the combinations. Even though this study was done using only one strain of B. cinerea, results showed that the tested indigenous South African plant species possess natural compounds that potentiate the activity of kresoxim-methyl.

  10. 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

  11. 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...

  12. 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

    This paper evaluates in vivo predictability of a battery of in vitro tests covering developmental toxicity and embryotoxicity of five widely used conazole fungicides. The conazoles were investigated in the embryonic stem cell test, and data were compared to in vivo embryotoxicity data. The same...

  13. Understanding the molecular basis of the resistance of Phytophthora infestans to fungicides by functional genomics

    Science.gov (United States)

    Development of resistance to fungicides is a major concern in managing potato late blight disease caused by Phytophthora infestans. The problem is P. infestans is capable of sexual recombination contributing to increased strain variability and high adaptability that hastens the development of resis...

  14. Production of biocontrol traits by banana field fluorescent Pseudomonads and comparison with chemical fungicide.

    Science.gov (United States)

    Shaikh, S S; Patel, P R; Patel, S S; Nikam, S D; Rane, T U; Sayyed, R Z

    2014-09-01

    Pseudomonas aeruginosa isolated from banana field rhizosphere produced different antifungal metabolites like bactriocin, hydrogen cyanide and siderophore. Bacteriocinogenic, siderophoregenic, and HCN rich broth of isolate inhibited the growth of phytopathogen like Aspergilus niger, Aspergilus flavus, Fusarium oxysporum and Alternaria alternata. The isolate exhibited more antifungal activity and comparatively low MIC vis-a-vis commonly used copper based systemic chemical fungicide;bil cop.

  15. 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

  16. Studies on the response of soil microflora to the application of the fungicide fenhexamid

    DEFF Research Database (Denmark)

    El Azhari, Najoi

    2007-01-01

    The aim of this work was to evaluate the impact of the fungicide fenhexamid (FEX) on the genetic structure of soil bacterial communities using the Ribosomal Intergenic Spacer Analysis molecular technique. Using real-time PCR, we also tried to quantify the pcaH sequences which encode the dioxygena...

  17. The implications of copper fungicide usage in vineyards for earthworm activity and resulting sustainable soil quality

    NARCIS (Netherlands)

    Eijsackers, H.J.P.; Beneke, P.; Maboeta, M.; Louw, J.P.E.; Reinecke, A.J.

    2005-01-01

    To investigate the impact of copper-containing fungicides (copper oxychloride) on earthworms in South African vineyards, field inventories of earthworms in and between vine rows were carried out and compared to directly adjacent grassland. Also copper content, pH, organic matter content, and soil po

  18. Modeling losses of copper-based fungicide foliar sprays in wash-off under simulated rain

    DEFF Research Database (Denmark)

    Pérez-Rodríguez, P.; Paradelo Pérez, Marcos; Soto-Gómez, D.

    2015-01-01

    Wash-off experiments of three Cu-based fungicides were conducted with a single raindrop simulator with known drop size and fall height. Losses were quantified as total Cu (CuT), in solution (CuL), and particulate (CuP). Cu wash-off time course was modeled for two different drop sizes using a stoc...

  19. THE FUNGICIDE PROCHLORAZ: IN VITRO ANDROGEN ANTAGONISM, PARTURITION DELAYS, AND MALE REPRODUCTIVE MALFORMATIONS IN RATS

    Science.gov (United States)

    The Fungicide Prochloraz: In vitro Androgen Antagonism, Parturition Delays, and Male Reproductive Malformations in Rats.Nigel C. Noriega, Joseph Ostby, Christy Lambright, Vickie S. Wilson, and L. Earl Gray Jr., noriega.nigel@epa.govUS EPAProchloraz (PZ) is an imid...

  20. 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.

  1. 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...

  2. Evaluating fungicide sensitivity of regional Blumeria graminis f.sp. tritici populations in the United States

    Science.gov (United States)

    Blumeria graminis f.sp. tritici (Bgt), cause of wheat powdery mildew, has a high likelihood of developing fungicide resistance because of the large quantity of spores produced along with the mixed mode of reproduction. Additionally, once reduced sensitivity appears in a population it can influence n...

  3. 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.

  4. Adsorption behaviors of fungicide-derived copper onto various size fractions of aggregates from orchard soil.

    Science.gov (United States)

    Wang, Quan-Ying; Hu, Bo; Yu, Hong-Wen

    2016-12-01

    Although the gradual accumulations of Cu in orchard soils due to the application of Cu-based fungicides have been widely reported, limited information is available about the retention characteristics of fungicide-derived Cu in soil, especially in various size soil aggregates. This study described the adsorption characteristics of Cu from commonly used fungicide, Bordeaux mixture (CuSO4 + Ca(OH)2), onto various aggregate fractions (2000-1000, 1000-500, 500-250, 250-106, and orchard soil. The Cu(NO3)2 was selected as a comparison. Two different types of adsorption experiments were conducted as follows: variable pH and variable Cu concentration experiments. The adsorption processes of Bordeaux mixture and Cu(NO3)2 onto the studied soil samples followed well with the Freundlich isotherm, and the adsorption isotherms were the S shaped. The adsorption amounts of Cu from different Cu compounds differed, and Bordeaux mixture can result in more Cu retention in soil than Cu(NO3)2. The adsorption ability of different size soil aggregates varied, and it was mainly governed by soil properties. The findings of this study suggested that both the chemical compositions of Cu compounds and the soil physical structure should be taken into account when performing soil Cu retention experiments with fungicide-derived Cu.

  5. Non-Hodgkin Lymphoma risk and insecticide, fungicide and fumigant use in the Agricultural Health Study

    Science.gov (United States)

    Farming and pesticide use have previously been linked to non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia (CLL) and multiple myeloma (MM). We evaluated agricultural use of specific insecticides, fungicides, and fumigants and risk of NHL and NHL-subtypes (including CLL an...

  6. Determination of fungicide resistance in Botrytis cinerea from strawberry in the Central Coast Region of California

    Science.gov (United States)

    A study was conducted in 2013 to investigate the occurrence of fungicide resistance in Botrytis cinerea populations in California’s northern strawberry growing region; specifically in Watsonville and Salinas. In mid-May, 59 samples consisting of a single diseased fruit or plant part with gray mold s...

  7. Control of speck rot in apple fruit caused by Phacidiopycnis washingtonensis with pre- and postharvest fungicides

    Science.gov (United States)

    Speck rot caused by Phacidiopycnis washingtonensis is a recently reported postharvest fruit rot disease of apple. Infection of apple fruit by the fungus occurs in the orchard, but symptoms develop during storage. In this study, selected pre- and postharvest fungicides were evaluated for control of s...

  8. Non-Hodgkin Lymphoma risk and insecticide, fungicide and fumigant use in the Agricultural Health Study

    Science.gov (United States)

    Farming and pesticide use have previously been linked to non-Hodgkin lymphoma (NHL), chronic lymphocytic leukemia (CLL) and multiple myeloma (MM). We evaluated agricultural use of specific insecticides, fungicides, and fumigants and risk of NHL and NHL-subtypes (including CLL an...

  9. Activation of stress signalling pathways enhances tolerance of fungi to chemical fungicides and antifungal proteins.

    Science.gov (United States)

    Hayes, Brigitte M E; Anderson, Marilyn A; Traven, Ana; van der Weerden, Nicole L; Bleackley, Mark R

    2014-07-01

    Fungal disease is an increasing problem in both agriculture and human health. Treatment of human fungal disease involves the use of chemical fungicides, which generally target the integrity of the fungal plasma membrane or cell wall. Chemical fungicides used for the treatment of plant disease, have more diverse mechanisms of action including inhibition of sterol biosynthesis, microtubule assembly and the mitochondrial respiratory chain. However, these treatments have limitations, including toxicity and the emergence of resistance. This has led to increased interest in the use of antimicrobial peptides for the treatment of fungal disease in both plants and humans. Antimicrobial peptides are a diverse group of molecules with differing mechanisms of action, many of which remain poorly understood. Furthermore, it is becoming increasingly apparent that stress response pathways are involved in the tolerance of fungi to both chemical fungicides and antimicrobial peptides. These signalling pathways such as the cell wall integrity and high-osmolarity glycerol pathway are triggered by stimuli, such as cell wall instability, changes in osmolarity and production of reactive oxygen species. Here we review stress signalling induced by treatment of fungi with chemical fungicides and antifungal peptides. Study of these pathways gives insight into how these molecules exert their antifungal effect and also into the mechanisms used by fungi to tolerate sub-lethal treatment by these molecules. Inactivation of stress response pathways represents a potential method of increasing the efficacy of antifungal molecules.

  10. TOXICITY PROFILES IN RATS TREATED WITH TUMORIGENIC AND NONTUMORIGENIC TRIAZOLE CONAZOLE FUNGICIDES: PROPICONAZOLE, TRIADIMEFON, AND MYCLOBUTANIL

    Science.gov (United States)

    Conazoles are a class of azole based fungicides used in agriculture and as pharmaceutical products. They have a common mode of antifungal action through inhibition of ergosterol biosynthesis. Some members of this class have been shown to be hepatotoxic and will induce mouse hepa...

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

    NARCIS (Netherlands)

    Roelofs, Maarke J.E.; Temming, A. Roberto; Piersma, Aldert H.; van den Berg, Martin; van Duursen, Majorie B.M.

    2014-01-01

    Abstract 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), f

  12. EFFECTS OF CONAZOLE FUNGICIDES ON DEVELOPMENT AND PARTURITION IN THE RAT

    Science.gov (United States)

    Conazoles are fungicides used extensively in agriculture and as pharmaceuticals. As part of an effort to evaluate the changes in gene expression corresponding to reproductive toxicity, we examined the effects of three conazoles on pregnancy and neonates. Wistar Han rats were expo...

  13. Direct analysis of dithiocarbamate fungicides in fruit by ambient mass spectrometry

    NARCIS (Netherlands)

    Cajka, T.; Riddelova, K.; Zomer, P.; Mol, J.G.J.; Hajslova, J.

    2011-01-01

    Dithiocarbamates (DTCs) are fungicides that require a specific single-residue method for detection and verification of compliance with maximum residue limits (MRLs) as established for fruit and vegetables in the EU. In this study, the use of ambient mass spectrometry was investigated for specific de

  14. Fate and distribution of pyrimethanil, metalaxyl, dichlofluanid and penconazol fungicides from treated grapes intended for winemaking.

    Science.gov (United States)

    Vaquero-Fernández, L; Sanz-Asensio, J; López-Alonso, M; Martínez-Soria, M T

    2009-02-01

    Tempranillo grapes were immersed in solutions of pyrimethanil, metalaxyl, dichlofluanid and penconazol fungicides at different concentrations for several different times. Determinations of the fungicide residues was carried out by GC-NPD, with an additional confirmation by GC-MS. The percentage absorption was determined as well as the distribution between surface, skin and pulp of the grapes. The percentage absorption ranged from 7.2 to 85.5%. These values depended on the time the grapes were in contact with the fungicide solutions. Residues were mainly found in skins, with percentages in skins ranging from 66.3 to 90.3% of total residues. In pulp, these values ranged from 3.5 to 31.0%. The overall methodology was applied to the determination of pyrimethanil in Tempranillo grapes treated with the recommended doses, respecting the safety period. Pyrimethanil residues found in treated grapes were higher in the skin. In grapes collected within the safety period (21 days), the levels found for fungicide residues were below maximum residues levels.

  15. The effects of humic substances on the activity of metalaxyl+mancozeb, fungicide

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, C.; Li, S.; Li, B.; Zhang, Q. [Chinese Academy of Sciences, Taiyuan (China). State Key Lab of Coal Conversion

    1999-07-01

    The effects of three dissolved humic substances on the activity of the fungicide metalaxy+mancozeb against the phytophthora were studied. The zone of inhibition technique was used. A synergistic effect was observed and the mechanism of the interaction is discussed. 16 refs., 2 figs., 1 tab.

  16. Significance of soil properties in the adsorption and mobility of the fungicide metalaxyl in vineyard soils.

    Science.gov (United States)

    Andrades, M S; Sánchez-Martín, M J; Sánchez-Camazano, M

    2001-05-01

    Adsorption and mobility of the fungicide metalaxyl were studied in 16 vineyard soils from the La Rioja region (Spain), with organic matter (OM) contents in the 0.31--1.37% range, and in 7 natural soils with OM contents in the 3.30--8.24% range. Adsorption isotherms were obtained using the batch equilibrium technique, and mobility was studied by soil thin-layer chromatography (soil-TLC). In all cases, the adsorption isotherms fit the Freundlich equation. The values of the K(f) constants were low in the vineyard soils (0.01--0.64) and increased in the natural soils (1.05--2.83). The n(f) values were in general lower than unity. K(f) constants were significantly correlated (p metalaxyl with soil-TLC indicated that in vineyard soils the fungicide has the potential for being highly mobile in 19% of the soils and mobile in 81% of them. In natural soils, the fungicide has the potential for being moderately mobile or mobile in 86 and 14% of the soils, respectively. This type of behavior of metalaxyl indicates that in vineyards soils of the La Rioja region (Spain) with low OM contents, where application of the compound is continuous, a leaching of the fungicide from the soil to groundwaters could potentially occur. These results should be borne in mind when metalaxyl is to be used in the soils of this region.

  17. Effect of fungicide Euparen Multi (Tolylfluanid) on the induction of chromosomal aberations in cultivated bovine lymphocytes.

    Science.gov (United States)

    Orosová, Martina; Holečková, Beáta; Siviková, Katarína; Dianovský, J

    2010-12-01

    The effect of the fungicide Euparen Multi (containing 50% tolylfluanid) was investigated on the induction of chromosomal aberrations (CA) in cultured bovine peripheral lymphocytes. Cultures from two healthy donors were treated with tolylfluanid-based fungicide at concentrations ranging from 1.7 to 17.5 μg/ml for the last 24 and 48 hours of cultivation. Conventional cytogenetic method (CA assay) with Giemsa staining as well as fluorescence in situ hybridization (FISH) with whole bovine chromosomes 1 and 5 painting probes were used in the experiment. In the CA assay, no clastogenic effect of the fungicide was found after Euparen Multi treatment for 24 hours. On the contrary, significant elevation in polyploidy induction was observed with dose-dependence in one of the donors. Using prolonged time of exposure to the fungicide (the last 48 h of the cultivation), a slight clastogenic effect was detected at the doses of 8.75 and 17.5 μg/ml (P lymphocytes by two-colour FISH (48 h exposure) using bovine chromosome painting probes revealed the presence of nonreciprocal translocations at two examined concentrations (3.5 μg/ml and 8.75 μg/ml).

  18. Comparative in vitro-in vivo percutaneous penetration of the fungicide ortho-phenylphenol

    NARCIS (Netherlands)

    Cnubben, N.H.P.; Elliott, G.R.; Hakkert, B.C.; Meuling, W.J.A.; Sandt, J.J.M. van de

    2002-01-01

    The validity of in vitro and in vivo methods for the prediction of percutaneous penetration in humans was assessed using the fungicide ortho-phenylphenol (OPP) (log Po/w 3.28, MW 170.8, solubility in water 0.7 g/L). In vivo studies were performed in rats and human volunteers, applying the test compo

  19. 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 con

  20. Chitosan and fungicides on postharvest control of Guignardia citricarpa and on quality of 'Pêra Rio' oranges

    Directory of Open Access Journals (Sweden)

    Maria Cristina Canale Rappussi

    2011-09-01

    Full Text Available Citrus fruits are affected by the black spot disease caused by the fungus Guignardia citricarpa. Chitosan can be used as covering for fruits and may delay the ripening process and inhibit the growth of some fungi. Thus, the control of citrus black spot using chitosan and the fungicides thiabendazole and imazalil was assessed in addition to the physicochemical quality of 'Pêra Rio' oranges. The oranges were immersed into chitosan, thiabendazole or imazalil, and in chitosan mixed with both fungicides. The fruits were then stored at 25 °C, 80% RH, for 7 days and, after this storage period, subjected to physicochemical analyses. Chitosan in association with the fungicides reduced black spot in 'Pêra Rio' oranges and delayed the change in the orange skin colour from green to yellow during the postharvest storage. Total soluble solids, titratable acidity, pH, ascorbic acid content and ratio were not influenced by the treatments. Thus, chitosan applied with the fungicides thiabendazole and imazalil showed potential to control the development of black spot lesions on 'Pêra Rio' oranges during the postharvest period.

  1. Efficacy of Fungicides for Control of Rosette and Post-harvest Fruit Diseases of Blackberries

    Science.gov (United States)

    Rosette disease (caused by the fungus Cercosporella rubi) is often severe on erect blackberries grown in the southeastern U.S. and, if not controlled, may limit fruit production. A series of trials were conducted in south Mississippi to determine fungicide efficacy and optimum timing of applications...

  2. METABOLOMIC EVALUATION OF RAT LIVER AND TESTIS TO CHARACTERIZE THE TOXICITY OF TRIAZOLE FUNGICIDES

    Science.gov (United States)

    The effects of two triazole fungicides, myclobutanil and triadimefon, on endogenous rat metabolite profiles in blood serum, liver, and testis was assessed using proton nuclear magnetic resonance (1H-NMR) spectroscopy. Adult male Sprague-Dawley rats were dosed daily by gavage for...

  3. Ranking of fungicides according to risk assessments for health and environment

    DEFF Research Database (Denmark)

    Jørgensen, Lise Nistrup; Ørum, Jens Erik

    2014-01-01

    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...

  4. Field evaluation of fungicides for control of Ascochyta blight of chickpea, 2015

    Science.gov (United States)

    Ascochyta blight of chickpea caused by the fungal pathogen Ascochyta rabiei is one of the most important foliar diseases of chickpea in the United State and elsewhere. Management of the disease is through using moderately resistant cultivars and application of fungicides. In order to evaluate foli...

  5. Effect of nitrogen fertilization and fungicides on Botryosphaeria stem blight lesion development on detached blueberry stems

    Science.gov (United States)

    Botryosphaeria stem blight is a destructive disease of blueberries. Field observations indicate stem blight is more severe on vigorous plants than on slower growing plants. Two studies compared the effect of two types of fertilizers applied at four rates and nine fungicides on lesion development fo...

  6. Oxidative damages in isolated rat hepatocytes treated with the organochlorine fungicides captan, dichlofluanid and chlorothalonil.

    Science.gov (United States)

    Suzuki, Toshihide; Nojiri, Hisao; Isono, Hideo; Ochi, Takafumi

    2004-11-15

    The cytotoxicity and lipid peroxidative potency of the organochlorine fungicides captan (N-(trichloromethylthio)-4-cyclohexene-1,2-dicarboximide), dichlofluanid (N-dichlorofluoromethylthio-N'N'-dimethyl-N-phenylsulfamide) and chlorothalonil (2,4,5,6-tetrachloro-isophthalonitrile) were studied in isolated rat hepatocytes. These fungicides induced cytotoxicity and lipid peroxidation in a dose- and time-dependent manner. Considerable cytotoxicity and lipid peroxidation occurred after cells were treated with 25 microM and more of fungicide. The phosphatidylcholine hydroperoxide (PCOOH) content increased more than 300 times by captan (250-1000 microM), 400 times by dichlofluanid (250-1000 microM) and 20 times by chlorothalonil (25-1000 microM) after 1h of incubation, as compared with untreated control. Significant cytotoxicity occurred after 20 min (captan), 30 min (dichlofluanid) and 60 min (chlorothalonil) of incubation and lipid peroxidation was induced prior to cytotoxicity. The antioxidant alpha-tocopherol and cytochrome P450 inhibitor SKF-525A effectively prevented cytotoxicity and lipid peroxidation. Our results suggest that metabolites of these fungicides produced by the microsomal cytochrome P450 system, induced membrane phospholipid peroxidation that caused cytotoxicity.

  7. Exposure to fungicides in fruit growing: Re-entry time as a predictor for dermal exposure

    NARCIS (Netherlands)

    Tielemans, E.; Louwerse, E.; Cock, J. de; Brouwer, D.; Zielhuis, G.; Heederik, D.

    1999-01-01

    As part of a European Concerted Action on Male Reproduction Capability an exposure assessment survey was conducted among seasonal workers in the fruit growing sector in the Netherlands. Dermal exposure to the fungicides captan and tolylfluanid was measured using cotton gloves (12 persons) and skin p

  8. 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.

  9. Fungicide spray coverage from ground-based sprayers in mature pecan trees

    Science.gov (United States)

    Air-blast sprayers are widely used to control pecan scab (Fusicladium effusum) on pecan trees. Good spray coverage is critical to ensure disease control and to minimize risk of fungicide resistance. Spray coverage from an air-blast sprayer, typical of the sprayer used by commercial producers, was me...

  10. 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.

  11. Fungicide resistance status in French populations of the wheat eyespot fungi Oculimacula acuformis and Oculimacula yallundae.

    Science.gov (United States)

    Leroux, Pierre; Gredt, Michel; Remuson, Florent; Micoud, Annie; Walker, Anne-Sophie

    2013-01-01

    Eyespot, caused by Oculimacula acuformis and Oculimacula yallundae, is the major foot disease of winter wheat in several European countries, including France. It can be controlled by chemical treatment between tillering and the second node stage. The fungicides used include antimicrotubule toxicants (benzimidazoles), inhibitors of sterol 14α-demethylation (DMIs) or of succinate dehydrogenase (SDHIs), the anilinopyrimidines cyprodinil and the benzophenone metrafenone. Since the early 1980s, a long-term survey has been set up in France to monitor changes in the sensitivity of eyespot populations to fungicides. Resistance to benzimidazoles has become generalised since the early 1990s, in spite of the withdrawal of this class of fungicides. In the DMI group, resistance to triazoles is generalised, whereas no resistance to the triazolinethione prothioconazole has yet developed. Resistance to the imidazole prochloraz evolved successively in O. acuformis and O. yallundae and is now well established. Specific resistance to cyprodinil has also been detected, but its frequency has generally remained low. Finally, since the early 2000s, a few strains of O. yallundae displaying multidrug resistance (MDR) have been detected. These strains display low levels of resistance to prothioconazole and SDHIs, such as boscalid. Knowledge of the spatiotemporal distribution in France of O. acuformis and O. yallundae field strains resistant to fungicides allows resistance management strategies for eyespot fungi in winter wheat to be proposed.

  12. 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.

  13. The effect of fungicidal treatment on selected quality parameters of barley and malt.

    Science.gov (United States)

    Havlová, Pavla; Lancová, Katerina; Vánová, Marie; Havel, Josef; Hajslová, Jana

    2006-02-22

    Protection of barley grain against contamination by fungi such as Fusarium spp., particularly by those producing mycotoxins, secondary metabolites with adverse health effects, is of principal importance. Fungicides applied immediately after full heading of spring barley is one method of direct protection. In this work, extensive two-year field experiments combined with a detailed chemical laboratory analysis (barley and malt) were performed with the aim to study the effect of previous crops, different fungicides, and other conditions on the selected barley and malt quality parameters (content of beta-glucans, pentosans, oxalic acid, deoxynivalenol, and gushing), while the main task was to follow the effect of the fungicide (used as a treatment to protect against pathogens, mostly Fusarium) on changes of the chemical composition in barley and malt, and gushing. It was found that the relationship between the studied factors and the parameters usually applied to the evaluation of barley and malt quality is quite complex and not straightforward. The responses show typical features of a multifactorial influence with both positive and negative correlations resulting in a decrease or increase in grain quality (concentrations of beta-glucans, pentosans, deoxynivalenol, and other studied parameters). The role of previous crops was also found to be important. The fungicides should be applied at the time of heading but not at the very beginning of this period.

  14. Controlled release fungicide, soil amendments and biofumigation effects on cotton root rot suppression

    Science.gov (United States)

    The cotton root rot pathogen (Phymatotrichopsis ominora) causes major losses in cotton produced in the Southwest. Granular controlled release formulations (CRF) of the fungicide, Propiconazole, developed to be soil applied at planting were studied at 1.0 and 3.0 lb a.i./ac. applications and with tw...

  15. Evaluation of natural products as potential agrochemical agents with insecticide, fungicide and herbicide activities

    CSIR Research Space (South Africa)

    Dumontet, V

    2012-07-01

    Full Text Available The International Congress on Natural Products Research, New York City, 28 July - 1 August 2012 Evaluation of natural products as potential agrochemical agents with insecticide, fungicide and herbicide activities V Dumontet 1, M Litaudon 1, F Olivon 1, C...

  16. Control of clavicipitaceous anamorphic endophytes with fungicides, aerated steam and supercritical fluid CO2-seed extraction

    Science.gov (United States)

    A. Dan Wilson; Donald G. Lester; Brian K. Luckenbill

    2008-01-01

    The effects of soil drenches with systemic fungicides on viability of clavicipitaceous anamorphic endophytes, non-choke inducing endosymbiotic fungi of the genus Neotyphodium that systemically infect grasses, were tested in endophyte-infected seedlings of Hordeum brevisubulatum subsp. violaceum, Lolium perenne...

  17. 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.

  18. Inhibition of fungal plant pathogens by synergistic action of chito-oligosaccharides and commercially available fungicides.

    Directory of Open Access Journals (Sweden)

    Md Hafizur Rahman

    Full Text Available Chitosan is a linear heteropolymer consisting of β 1,4-linked N-acetyl-D-glucosamine (GlcNAc and D-glucosamine (GlcN. We have compared the antifungal activity of chitosan with DPn (average degree of polymerization 206 and FA (fraction of acetylation 0.15 and of enzymatically produced chito-oligosaccharides (CHOS of different DPn alone and in combination with commercially available synthetic fungicides, against Botrytis cinerea, the causative agent of gray mold in numerous fruit and vegetable crops. CHOS with DPn in the range of 15-40 had the greatest anti-fungal activity. The combination of CHOS and low dosages of synthetic fungicides showed synergistic effects on antifungal activity in both in vitro and in vivo assays. Our study shows that CHOS enhance the activity of commercially available fungicides. Thus, addition of CHOS, available as a nontoxic byproduct of the shellfish industry, may reduce the amounts of fungicides that are needed to control plant diseases.

  19. Effect of nitrogen fertilization and fungicides on Botryosphaeria stem blight lesion development on detached stems

    Science.gov (United States)

    : Botryosphaeria stem blight is a destructive disease of blueberries that has not been well managed with fungicides. Field observations showed that stem blight is more severe on vigorously growing plants than on slower growing plants. Detached stem assays were used to compare the effect of fertil...

  20. Irrigation and fungicide application on disease occurrence and yield of early and late sown sunflower

    Directory of Open Access Journals (Sweden)

    Ivan C. Maldaner

    2015-07-01

    Full Text Available The objective of this study was to evaluate the effect of irrigation and fungicide application on the occurrence of diseases and cypsela yield of two genotypes of sunflower. The experiments were carried out in Santa Maria-RS, during the regular season in 2007 and the late season, in 2008. Plants were sown on 04/09/2007 and 21/01/2008, in a completely randomized design, with four replicates. A 2 x 6 factorial scheme was used, with the sunflower genotypes Aguará 03 and Hélio 358 and six fungicide application schemes, which were determined by the FAST forecasting system, as follows: FAST 16, FAST 22 and FAST 28, without irrigation, FAST 16 IRR under irrigated condition, in addition to irrigated control (CONTROL IRR and control (CONTROL. Disease progress was analyzed based on weekly observations of the severity of the symptoms. It was verified that irrigation increases sunflower cypsela yield in the regular season, provided that weather conditions are not favorable for the occurrence of alternaria and septoria leaf blights or that fungicides are applied. In the late season, under irrigated condition, fungicide application is necessary to control alternaria and septoria leaf blights.

  1. Alternative Fungicide Spraying for the Control of Powdery Mildew Caused by Sphaerotheca fusca on Greenhouse Watermelon (Citrullus lanatus

    Directory of Open Access Journals (Sweden)

    Hyo-Jung Kang

    2014-03-01

    Full Text Available Alternative spraying was developed using fungicides and potassium phosphonate to control watermelon powdery mildew (WPM caused by Sphaerotheca fusca under greenhouse condition. In 2010 trial, a total of 9 combinations of 6 fungicides which are legally registered in Korea and currently used on watermelon farms were tested for the control efficacy against WPM. Though the combination of chlorothalonil (Chl-myclobutanil (My-fenarimol (Fen-hexaconazole (Hex was the most effective (82.6% in the first-year trial, it had the problem that My, Fen and Hex have the same mode of action. Therefore, in the second-year trial to improve the fungicide combination and to reduce fungicide application, fungicides and potassium phosphonate (P combinations were tested for WPM control using 500 ppm aqueous potassium phosphonate solution which is both eco-friendly and showing different mode of action from the fungicides tested. The P-My-Fen-Hex applied at 10-day intervals provided relatively high control (75.6%, whereas Chl-My-Fen-P provided 31.8% control. To improve the control, fungicides and P were applied at 7-day intervals in the third-year trial. Though Chl-My-Fen-Hex provided the highest control (89.6%, P-My-Fen-Hex also provided relatively high control (83.5% compared to 65.9 % control with Chl-My-Fen-P, which suggests that Chl-My-Fen-Hex could be replaced with P-My-Fen-Hex for WPM control.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. Relationship between IC50 determined in vitro/in vivo and the fungicide rate used in the Field

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    Erlei Melo Reis

    2015-03-01

    Full Text Available Published data containing fungicide concentrations that control 50% (IC50 of a given fungus were analyzed. In the analysis we considered: (i the IC50 determined in vitro and in vivo for a given fungicide and for a specific fungus; (ii the concentration (g/ha of active ingredient for the fungicide indicated to control a specific disease in the field; (iii water volume of 120/L used in the spray; (iv the fungicide a.i. concentration (mg/L in 120 L volume; (v and the ratio of the concentration used in the field with that determined in the laboratory. The analysis were performed by using IC50 data for DMIs, QoIs, a carbamate and a benzimidazol against the following fungi Bipolaris sorokiniana, Drechslera tritici-repentis, D. siccans, Fusarium graminearum, Puccinia triticina, Exserohilum turcicum, Phakopsora pachyrhizi and Corynespora cassiicola. The fungicide concentrations sprayed in the field were 33.9 (D. siccans and trifloxystrobin to 500,000.0 (E. turcicum and iprodione times higher than that determined in the laboratory. It was concluded that the IC50 was not related to the concentration used in the field and therefore should be used to compare the power among fungicides and to monitor the fungal sensitivity shift towards fungicides

  8. 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

  9. 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.

  10. Sensitivity to four systemic fungicides of Colombian isolates of Phytophthora infestans

    Directory of Open Access Journals (Sweden)

    Hibert Giovani García

    2008-04-01

    Full Text Available Potato late blight caused by Phytophthora infestans is the most restrictive disease of this crop in Colombia , where environmental conditions are optimal conditions for its epidemic development. This situation leads to an excessive use of fungicides by farmers, which besides representing near 10% of production costs, causes a serious damage of environment and public health. This research pretends to support IPM programs by monitoring the sensitivity levels of 15 isolates of P. infestans obtained from crops in Antioquia, Cundinamarca and Boyacá, to fungicides Ridomil® Gold, Curzate® M-8, Previcur® N SL and Mildex® 711 WG as a tool of the risk analysis that permit to offer to the farmers the technical recommendations based on the generation of sensitivity lines. Evaluations of sensitivity were carried out using the immersion of leaf discs methodology with seven doses of each commercial product. Results show that the studied population presents high levels of sensitivity to these fungicides. In the case of Curzate® M-8, the average EC50 value was 0.28 mg·L-1, while the EC50 for Previcur® N SL reached 0.71 mg·L- . Intests with fungicides Ridomil® Gold and Mildex® 711 WG, these values were 0.62 and 0.54 mg·L-1, respectively. Finally, sporangia production decreased from an average of 41,181 sporangia/mL in control treatment to less than 500 sporangia/mL when the maximum doses of four fungicides were evaluated.

  11. The effect of fungicides on seed yield and disease control in Italian ryegrass.

    Science.gov (United States)

    Rijckaert, G

    2009-01-01

    Under Belgian climatic conditions, the incidence of fungal diseases like mildew, crown rust and stem rust is much lower in seed crops of Italian ryegrass than crops of perennial ryegrass, because of the cleaning effect of the preceding forage cut and the much quicker growing rate of Italian ryegrass. However, in some mild and warm seasons, above diseases can give detrimental effects on seed yield, so a preventive fungicide programme would be very recommended in order to obtain consistently high seed yields over the years. Six different fungicides and an untreated control were tested on two tetraploid varieties of Italian ryegrass, namely cv. Meroa and cv. Salomé (more tolerant to crown rust); one fungicide application took place at early ear emergence for all three trials (2006-07-08). Only in the 2007-trial with very severe rust pressure, the most efficient fungicides increased seed yield by 22-25 % against the control (100%) and the tebuconazol-treatment (106.6%). Yield differences could be attributed to a healthier seed crop, i.e., less withered flag leaf and to a higher thousand seed weight. As both years 2006 and 2008 had very little disease pressure throughout the season, the best treatments (Allegro and Opera) resulted in a moderate seed yield increase of 6-7% in 2006, while 2008 did not give any yield response at all between the fungicide treatments and the untreated check. Seed yield, yield components and disease development are discussed and explained in relation to the seasonal meteorological conditions.

  12. Mechanisms and significance of fungicide resistance Mecanismos e significância da resistência a fungicidas

    Directory of Open Access Journals (Sweden)

    Holger B. Deising

    2008-06-01

    Full Text Available In this review article, we show that occurrence of fungicide resistance is one of the most important issues in modern agriculture. Fungicide resistance may be due to mutations of genes encoding fungicide targets (qualitative fungicide resistance or to different mechanisms that are induced by sub-lethal fungicide stress. These mechanisms result in different and varying levels of resistance (quantitative fungicide resistance. We discuss whether or not extensive use of fungicides in agricultural environments is related to the occurrence of fungicide resistance in clinical environments. Furthermore, we provide recommendations of how development of fungicide resistant pathogen populations may be prevented or delayed.A ocorrência de resistência a fungicidas é uma das mais importantes conseqüências da agricultura moderna. Este fato pode ser resultado de mutações em genes codificadores de resistência a fungicidas (resistência quantitativa ou a diferentes mecanismos que são induzidos por stresse devido a doses subletais dos produtos utilizados. Estes mecanismos produzem diferentes e variados níveis de resistência (resistência quantitativa. Também é discutido se o uso extensivo de fungicidas em ambientes agricultáveis é relacionado ou não com a ocorrência de resistência em ambientes clínicos. Além disso, também são fornecidas recomendações de como prevenir ou mesmo retardar o desenvolvimento de resistência a fungicidas em patógenos.

  13. Presence of Fungicides Used to Control Asian Soybean Rust in Streams in Agricultural Areas in the United States

    Science.gov (United States)

    Sandstrom, M. W.; Battaglin, W. A.

    2007-05-01

    Concentrations of 11 fungicides were measured in stream samples during 2 years in agricultural areas in the United States that grow predominantly corn and soybean. The fungicides are registered for control of Asian Soybean Rust (ASR), which entered the United States in 2004. Many of these fungicides were registered under an emergency exemption because evaluation of environmental risks related to their widespread use on soybeans had not been completed. Some of these fungicides are considered moderately to highly toxic to fish and aquatic invertebrates. We developed a solid-phase extraction and gas chromatography/mass spectrometry method for determining the fungicides at low concentrations (ng/L). Stream samples were collected 2 to 4 times at study areas during the late spring through fall season when fungicides are applied. Six fungicides registered for control of ASR (Phakospora pachyrhizi) in 2005 were measured in streams in Alabama, Georgia, North Carolina, South Carolina, and Mississippi during August-November, 2005. One or more fungicides were detected in 8 of the 12 streams sampled. Azoxystrobin, pyraclostrobin, propiconazole, tebuconazole, and myclobutanil were found in at least one of the 40 samples collected, while chlorothalonil was not found. Azoxystrobin was detected most frequently, in 35 percent of the samples. In 2006, five additional fungicides registered for use in control of ASR were included in the analytical method. One or more of the fungicides (azoxystrobin, pyraclostrobin, trifloxystrobin, metconazole, propiconazole, tebuconazole, tetraconazole, myclobutanil) were detected in 12 of the 16 streams sampled from areas in the South and Midwest during May-September, 2006. Azoxystrobin was detected most frequently (40 percent of the samples) and the highest concentration was 1.1 μg/L in a small predominantly cotton and soybean watershed. The highest concentrations of azoxystrobin were measured prior to the spread of ASR in 2006, and the detections

  14. PATHOGENICITY TESTS AND EVALUATION OF EFFICACY OF FUNGICIDES AGAINST RHIZOCTONIA BATATICOLA, THE CAUSAL AGENT OF DRY ROOT ROT OF CHICKPEA

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    G Amrutha Veena

    2014-03-01

    Full Text Available The pathogen was identified based on its mycelial and sclerotial characters and pathogenicity test was proved by soil inoculation method. Efficacy of two non systemic fungicides (copper oxychloride and captan, two systemic fungicides (hexaconazole and tebuconazole and one antifungal antibiotic validamycin each at different concentrations were tested against Rhizoctonia bataticola, incitant of dry root rot of chickpea under in vitro conditions. The fungicides copper oxychloride, captan, hexaconazole and tebuconazole were found to be highly effective (100% in inhibiting the mycelial growth of the highly virulent pathogen at all the concentrations tested.

  15. ENZYMOLOGY OF ARSENIC METHYLATION

    Science.gov (United States)

    Enzymology of Arsenic MethylationDavid J. Thomas, Pharmacokinetics Branch, Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park...

  16. Lysine methylation: beyond histones

    Institute of Scientific and Technical Information of China (English)

    Xi Zhang; Hong Wen; Xiaobing Shi

    2012-01-01

    Posttranslational modifications (PTMs) of histone proteins,such as acetylation,methylation,phosphorylation,and ubiquitylation,play essential roles in regulating chromatin dynamics.Combinations of different modifications on the histone proteins,termed 'histone code' in many cases,extend the information potential of the genetic code by regulating DNA at the epigenetic level.Many PTMs occur on non-histone proteins as well as histones,regulating protein-protein interactions,stability,localization,and/or enzymatic activities of proteins involved in diverse cellular processes.Although protein phosphorylation,ubiquitylation,and acetylation have been extensively studied,only a few proteins other than histones have been reported that can be modified by lysine methylation.This review summarizes the current progress on lysine methylation of nonhistone proteins,and we propose that lysine methylation,like phosphorylation and acetylation,is a common PTM that regulates proteins in diverse cellular processes.

  17. 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

  18. Functional characterization of a C-4 sterol methyl oxidase from the endomycorrhizal fungus Glomus intraradices.

    Science.gov (United States)

    Oger, Elodie; Ghignone, Stefano; Campagnac, Estelle; Fontaine, Joël; Grandmougin-Ferjani, Anne; Lanfranco, Luisa

    2009-01-01

    Sterols are crucial components of eukaryotic membranes that control membrane fluidity and permeability. They play an important role in cell signaling, polarity and sorting. Since many steps in the pathway are essential, sterol biosynthesis inhibitors (SBI) are widely used as antifungal agents. This work reports the identification and the characterization of a C-4 sterol methyl oxidase (SMO), the first gene involved in the sterol biosynthetic pathway, so far described from an arbuscular mycorrhizal fungus. The sequence, called GintSMO, shows a primary structure, a hydrophobicity profile and a pattern of histidine-rich motifs which are typical of C-4 methyl sterol oxidases. The complementation assay in a Saccharomyces cerevisiae mutant strain demonstrates that GintSMO encodes a functional SMO. Changes in GintSMO transcript levels and in the amount of the sterol precursor squalene were observed in in vitro grown extraradical structures exposed to the fenpropimorph SBI fungicide.

  19. ECONOMIC EVALUATION OF FUNGICIDE APPLICATION ON TARO (Colocasia esculenta LEAF BLIGHT

    Directory of Open Access Journals (Sweden)

    Tarla D N

    2014-05-01

    Full Text Available Taro is an important crop in Cameroon but yields of the crop has severely affected by pests and diseases especially leaf blight. An economic evaluation of fungicide applications on taro blight was conducted in Dschang, Cameroon, during the 2012 cropping season. A split-plot design was used, with two factors; fungicide and cultivar, replicated three times. Whole plots were assigned to five fungicide spray schedules (7, 14, 21, 28-day, and non-treated while sub-plots were assigned to two taro cultivars; the dark green petioles (“Ibo coco” cultivar and the light green petioles small leaves (“Ehkoueh’lah” cultivar. A fungicide, Plantomil 72 WP was applied at 3.33 kgha-1 . Blight severity was scored weekly in every sub-plot, and yields were obtained at harvest. Data was subjected to the analysis of variance. Standardized area under disease progress curve (SAUDPC was high (p = 0.005 in control plots compared to sprayed plots of the cultivars. The high SAUDPC values were correlated with low yields (16.11 t/ha in control plots of “Ibo coco” compared to high yields (60.44 to 62.11 t/ha in sprayed plots. For “Ehkoueh’lah”, yield differences between control and sprayed plots were not high, 33.11 tha-1 in the control compared to 46.83 to 49.06 tha-1 in sprayed plots. The highest yield increase of 74.06 and 32.51 % for “Ibo coco” and “Ehkoueh’lah”, respectively was obtained from 7-day sprayed plots. Economic analysis revealed that a 28-day fungicide spray frequency had the highest rate of return, 13.78 and 6.63 and net benefits of 8.26 and 4.76 million FCFAha-1 for “Ibo coco” and “Ehkoueh’lah”, respectively. Thus, taro leaf blight can be managed with monthly applications of fungicide.

  20. RESULTS OF SUGAR BEET PRODUCTION DEPENDING ON THE HYBRIDS SELECTION AND THE NUMBER OF FUNGICIDE APPLICATION

    Directory of Open Access Journals (Sweden)

    Andrija Kristek

    2015-12-01

    Full Text Available The study of the production values of 10 sugar beet hybrids was conducted on chernozem soil type in Eastern Croatia (Tovarniklocation. The used treatments with and without fungicides application were investigated in 2013 and 2014. Sugar beet hybrids used in the study originate from three market-leading sugar beet seed companies in Croatia, whose varieties provide disease tolerance to C. beticola. The years of the study were quite warm with higher mean monthly air temperature (°C and increased amount of rainfall, as compared to the long-term mean. In the second year of the study, due to increased amount of rainfall (mm in July and August, as well as the total loss ofstrobilurin efficiency and low effectiveness ofthe cyproconazole treatment, the destruction ofthe leaves by C. beticola Sacc. was significantly higher. The results of the study showed a huge coherence of sugar beet yield and quality with leaf conservation through the vegetation (the number of treatment, and with the hybrids. Due to leaves destruction on control treatments, as compared to fungicide application three times, the sugar beet root yield was reduced on the average by 9.79 t ha'1 (10.03%, sugar content by 0.69% (rel. 4.89% and sugar yield by 2.041 ha1 (17.04%. On the other hand, three fungicide applications increased the root yield by 4.881 ha1 (5.26%, sugar content by 0.52% and sugar yield by 0.99 t ha1 (9.01% as compared to one fungicide application. All sugar beet hybrids of the study were strongly negatively affected the control treatment, indicating repeated fungicide application against C. beticola as a regular agricultural practices. On the average, for all variations of fungicides applications, the sugar beet hybrid Jadranka had significantly higher root yield in comparison with other hybrids included in the study. Moreover, the highest sugar content achieved Sandor, Marianka and Kundera. Significantly higher sugar yield had a hybrid Jadranka.

  1. Application of zirconium dioxide nanoparticle sorbent for the clean-up step in post-harvest pesticide residue analysis.

    Science.gov (United States)

    Uclés, Ana; Herrera López, Sonia; Dolores Hernando, Maria; Rosal, Roberto; Ferrer, Carmen; Fernández-Alba, Amadeo R

    2015-11-01

    The use of yttria-stabilized zirconium dioxide nanoparticles as d-SPE clean-up sorbent for a rapid and sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for the determination of post-harvest fungicides (carbaryl, carbendazim, chlorpropham, diphenylamine, ethoxyquin, flutriafol, imazalil, iprodione, methomyl, myclobutanil, pirimiphos-methyl, prochloraz, pyrimethanil, thiabendazole, thiophanate-methyl and tolclofos-methyl) in orange and pear samples has been evaluated and validated. The sample preparation was a modification of the QuEChERS extraction method using yttria-stabilized zirconium dioxide and multi-walled carbon nanotubes (MWCNTs) nanoparticles as the solid phase extraction (d-SPE) clean-up sorbents prior to injecting the ten-fold diluted extracts into the LC system. By using the yttria-stabilized zirconium dioxide extraction method, more recoveries in the 70-120% range were obtained - thus this method was used for the validation. Quantification was carried out using a matrix-matched calibration curve which was linear in the 1-500 µg kg(-1) range for almost all the pesticides studied. The validated limit of quantification was 10 µg kg(-1) for most of the studied compounds, except chlorpropham, ethoxyquin and thiophanate-methyl. Pesticide recoveries at the 10 and 100 µg kg(-1) concentration levels were satisfactory, with values between 77% and 120% and relative standard deviations (RSD) lower than 10% (n=5). The developed method was applied for the determination of selected fungicides in 20 real orange and pear samples. Four different pesticide residues were detected in 10 of these commodities; 20% of the samples contained pesticide residues at a quantifiable level (equal to or above the LOQs) for at least one pesticide residue. The most frequently-detected pesticide residues were: carbendazim, thiabendazole and imazalil-all were below the MRL. The highest concentration found was imazalil at 1175 µg kg

  2. COMPARATIVE LIVER P450 ENZYME ACTIVITY AND HISTOPATHOLOGY IN MICE TREATED WITH THE CONAZOLE FUNGICIDES: MYCLOBUTANIL, PROPICONAZOLE AND TRIADIMETON

    Science.gov (United States)

    Conazoles used in agriculture and pharmaceutical products comprise a class of chemicals which inhibit ergosterol biosynthesis to act as fungicides. Both propiconazole and triadimefon are hepatotoxic and hepatotumorigenic in mice, while myclobutanil is not a mouse liver tumorigen....

  3. GENE EXPRESSION PROFILING IN THE LIVER OF CD-1 MICE TO CHARACTERIZE THE HEPATOTOXICITY OF TRIAZOLE FUNGICIDES

    Science.gov (United States)

    Four triazole fungicides used in agricultural or pharmaceutical applications were examined for hepatotoxic effects in mouse liver. Besides organ weight, histopathology, and cytochrome P450 (CYP) enzyme induction, DNA microarrays were used to generate gene expression profiles and ...

  4. TRANSCRIPTIONAL PROFILES IN LIVER FROM MICE TREATED WITH HEPATOTUMORIGENIC AND NON-HEPATOTUMORIGENIC TRIAZOLE CONAZOLE FUNGICIDES: PROPICONAZOLE, TRIADIMEFON, AND MYCLOBUTANIL

    Science.gov (United States)

    Conazoles are environmental and pharmaceutical fungicides. The present study relates the toxicological effects of conazoles to alterations of gene and pathway transcription and identifies potential modes of tumorigenic action. In a companion study (Allen et al. 2006) under...

  5. Fungicide-driven evolution and molecular basis of multidrug resistance in field populations of the grey mould fungus Botrytis cinerea

    NARCIS (Netherlands)

    Kretschmer, M.; Leroch, M.; Mosbach, A.; Walker, A.S.; Fillinger, S.; Mernke, D.; Schoonbeek, H.J.; Pradier, J.M.; Leroux, P.; Waard, de M.A.; Hahn, M.

    2009-01-01

    The grey mould fungus Botrytis cinerea causes losses of commercially important fruits, vegetables and ornamentals worldwide. Fungicide treatments are effective for disease control, but bear the risk of resistance development. The major resistance mechanism in fungi is target protein modification

  6. Présence en Tunisie d'isolats de Fusarium sambucinum résistants aux benzimidazoles : développement in vitro et agressivité sur tubercules de pomme de terre

    Directory of Open Access Journals (Sweden)

    El Mahjoub M.

    2006-01-01

    Full Text Available Presence in Tunisia of Fusarium sambucinum isolates resistant to benzimidazoles: in vitro growth and aggressiveness on potato tubers. The behaviour of 55 isolates of Fusarium spp. causing dry rot of the potato tubers, is studied against some enzimidazoles fungicides. Tunisian isolates of F. solani (12, F. oxysporum (23 and F. graminearum (10 are sensitive in vitro to carbendazime and benomyl at 5 mg.l-1. Their interaction with thiophanate-methyl is different; a complete inhibition of their mycelial growth is observed at doses higher than 500 mg.l-1. Tunisian isolates of F. sambucinum collected during 2002, 2003 and 2004 are resistant to these benzimidazoles showing existence of a cross-resistance. In fact, these isolates tolerated carbendazime (and benomyl at 200 mg.l-1 and thiophanate-methyl at 1000 mg.l-1. This is the first study in Tunisia indicating emergence of this type of F. sambucinum resistance. Control isolates of F. sambucinum and those treated with carbendazime at 100 mg.l-1 showed a similar aggressiveness on potato tubers of the Spunta cultivar.

  7. [Study on usage of pesticides in various countries].

    Science.gov (United States)

    Yamamoto, Miyako; Toda, Miou; Tanaka, Keiko; Sugita, Takiko; Sasaki, Shiho; Uneyama, Chikako; Morikawa, Kaoru

    2007-01-01

    Usage of pesticides in food items in export countries was studied, focusing items which Japan imports in large quantity. Japan has imported field crops such as wheat, corn and soy bean, and also grapefruit in large quantity on a weight base, mainly from United States, Australia and Canada. While, Japan has imported various kinds of vegetables in which China had the largest share. We collected usage data of pesticides for 44 food items of 17 countries of 2004. Pesticides which were used frequently (usage rank within top ten in each item/country) were dichlorvos, carbofuran, chlorpyrifos, dimethoate (insecticides), mancozeb, carbendazim, thiophanate-methyl, chlorthalonil (fungicides), glyphosate, 2,4-D, paraquat, acetochlor (herbicides). Carbendazim, thiophanate-methyl, acetochlor and dichlorvos were mainly used in China. Dithiocarbamates are used frequently in various food items in various countries, and also frequently detected in monitoring in foreign countries. Some pesticides such as bisultap, monosultap, etaboxam and triazmate were used only in certain countries, and available information on toxicity or analytical method was very limited. Some of pesticides described above have not been analyzed in the pesticide residue monitoring in Japan before 2005,however, many of them are subjects of analysis for import food after 2006 with the enforcement of positivelist system for residues of pesticide and veterinary medicines in food in Japan.

  8. Evaluation of fungicides enestroburin and SYP1620 on their inhibitory activities to fungi and oomycetes and systemic translocation in plants.

    Science.gov (United States)

    Liu, Pengfei; Wang, Haiqiang; Zhou, Yuxin; Meng, Qingxiao; Si, Naiguo; Hao, Jianjun J; Liu, Xili

    2014-06-01

    Enestroburin and SYP1620 are newly developed strobilurin chemicals carrying fungicidal activity and need to be fully characterized in activities of anti-oomycete or anti-fungi, disease prevention and systemic translocation in planta. Their inhibitory activities were examined by amending the chemical in agar media, on which selected plant pathogens were grown and mycelial growth were measured. Effective concentrations for 50% inhibition (EC50) of mycelial growth were calculated to determine the level of fungicide sensitivity of the pathogen. Azoxystrobin was used as control. To examine the prevention and systemic translocation in plants, the fungicides were either sprayed on wheat leaves or dipped on wheat roots, which then were detected using high performance liquid chromatography. All the three fungicides inhibited mycelial growth of Sphacelotheca reiliana, Phytophthora infestans, Peronophythora litchi, and Magnaporthe oryzae, with EC50 values ranging from 0.02 to 2.84μg/ml; EC50 of SYP1620 was significantly lower than that of azoxystrobin and enestroburin on Valsa mali, Gaeumannomyces graminis, Alternaria solani, and Colletotrichun orbiculare. The three QoI fungicides showed strong inhibitory activities on spore germination against the 13 pathogens tested and were highly effective on biotrophic pathogens tested. Enestroburin and SYP1620 penetrated and spread in wheat leaves, but the penetration and translocation levels were lower compared to azoxystrobin. The three fungicides were all rapidly taken up by wheat roots and transported upwards, with greater fungicide concentrations in roots than in stems and leaves. The results indicate that enestroburin and SYP1620 are systemic fungicides that inhibit a broad spectrum of fungi and oomycetes.

  9. REPCO 501452 : Replacement of copper fungicides in organic production of grapevine and apple in Europe : publishable final activity report

    OpenAIRE

    Köhl, J

    2007-01-01

    Final Activity Report: The objective of REPCO was to contribute to the replacement of copper fungicides in organic agriculture by new measures for control of downy mildew (Plasmopara viticola) in grapevine and scab (Venturia inaequalis) in apple. Both major European organic crops strongly depend on copper fungicides. Permitted amounts will be reduced stepwise in the years ahead (Council Regulation (EEC) 2092/91, Annex II) to avoid environmental risks. In European countries where copper fungic...

  10. Development of forecasting elements for minimization of fungicide treatment in potato protection against early blight in Moscow region

    OpenAIRE

    Penjkin Roman V.; Doroškina Ljudmila A.; Smirnov Aleksej N.

    2013-01-01

    Early blight of potato (the agent is imperfect fungus Alternaria alternata (Fr.) Keissl.) is a serious disease of potatoes under hot conditions. This disease is important in the regions of Eastern and Southern Europe, Asia and Africa. It is controlled with intensive application of fungicides commonly used against late blight. However, currently fungicides cause undesirable damage to humans and the environment. Elements of forecasting the early blight have been developed in order to mini...

  11. Simultaneous removal of five triazole fungicides from synthetic solutions on activated carbons and cyclodextrin-based adsorbents

    Directory of Open Access Journals (Sweden)

    Grégorio Crini

    2017-08-01

    Full Text Available In this study, an adsorption-oriented process for the removal of fungicides from polycontaminated aqueous solutions was applied. To remove triazole fungicides from aqueous mixtures of propiconazole (PROPI, tebuconazole (TEBU, epoxiconazole (EPOXI, bromuconazole (BROMU and difenoconazole (DIFENO, several materials used as adsorbents were compared using batch experiments, namely two conventional activated carbons (ACs and five nonconventional cross-linked cyclodextrin (CD-based materials (α-CDP, β-CDP, γ-CDP, αβγ-CDP mixture, and hydroxypropyl-β-CDP. This article presents the abatements obtained. As expected, ACs exhibited the highest levels of triazole fungicide removal: the treatment lowered the five azoles by more than 99%, and adsorption was non-selective. Concerning CD-based materials employed for the first time for the removal of fungicides from polycontaminated aqueous solutions, results were interesting in particular for hydroxypropyl-β-CDP: 1 g of adsorbent placed in 1 L of solution containing 1 mg of each of five triazoles (5 mg in total was able to remove over half of the fungicide amount (2.97 mg. The order obtained was the following: BROMU << PROPI ≅ EPOXI < TEBU << DIFENO. This indicates that, in the mixture studied, strong competition prevailed among fungicides for the binding sites.

  12. Dithiocarbamate fungicides increase intracellular Zn(2+) levels by increasing influx of Zn(2+) in rat thymic lymphocytes.

    Science.gov (United States)

    Kanemoto-Kataoka, Yumiko; Oyama, Tomohiro M; Ishibashi, Hitoshi; Oyama, Yasuo

    2015-07-25

    Dithiocarbamate fungicides are used as alternative antifouling agents to highly toxic organotin antifouling agents, such as tri-n-butyltin and triphenyltin. There are some concerns regarding their environmental and health risks. It has been shown that tri-n-butyltin increases intracellular Zn(2+) levels of mammalian lymphocytes. Therefore, we examined the effects of dithiocarbamate fungicides (Ziram, Thiram, and Zineb) on rat thymic lymphocytes using a flow-cytometric technique to elucidate how these fungicides affect intracellular Zn(2+) levels. We further determined whether the agents increase intracellular Zn(2+) and/or Ca(2+), because both Zn(2+) and Ca(2+) are intracellular signals in lymphocytes, and excessive increases in their intracellular concentrations can have adverse effects. Dithiocarbamate fungicides increased intracellular Zn(2+) levels, without affecting intracellular Ca(2+) levels. Ziram was the most potent compound, increasing intracellular Zn(2+) levels via Zn(2+) influx. Ziram (1μM) greatly decreased the cellular nonprotein thiol content, and Zn(2+) chelators attenuated the Ziram-induced decrease. Ziram increased the population of annexin V-positive cells in a Zn(2+)-dependent manner. Therefore, we propose that dithiocarbamate fungicides induce Zn(2+) influx, resulting in an excessive elevation of intracellular Zn(2+) levels, leading to the induction of apoptosis. This study gives a basic insight into the mechanisms of dithiocarbamate fungicide-induced adverse events.

  13. Evolution of cross-resistance to medical triazoles in Aspergillus fumigatus through selection pressure of environmental fungicides.

    Science.gov (United States)

    Zhang, Jianhua; van den Heuvel, Joost; Debets, Alfons J M; Verweij, Paul E; Melchers, Willem J G; Zwaan, Bas J; Schoustra, Sijmen E

    2017-09-27

    Resistance to medical triazoles in Aspergillus fumigatus is an emerging problem for patients at risk of aspergillus diseases. There are currently two presumed routes for medical triazole-resistance selection: (i) through selection pressure of medical triazoles when treating patients and (ii) through selection pressure from non-medical sterol-biosynthesis-inhibiting (SI) triazole fungicides which are used in the environment. Previous studies have suggested that SI fungicides can induce cross-resistance to medical triazoles. Therefore, to assess the potential of selection of resistance to medical triazoles in the environment, we assessed cross-resistance to three medical triazoles in lineages of A. fumigatus from previous work where we applied an experimental evolution approach with one of five different SI fungicides to select for resistance. In our evolved lines we found widespread cross-resistance indicating that resistance to medical triazoles rapidly arises through selection pressure of SI fungicides. All evolved lineages showed similar evolutionary dynamics to SI fungicides and medical triazoles, which suggests that the mutations inducing resistance to both SI fungicides and medical triazoles are likely to be the same. Whole-genome sequencing revealed that a variety of mutations were putatively involved in the resistance mechanism, some of which are in known target genes. © 2017 The Author(s).

  14. 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.

  15. Tratamento de sementes com fungicidas e inseticidas como redutores dos efeitos do estresse hídrico em plantas de soja Seed treatment with fungicides and insecticides reducing the hydric stress on soybean plants

    Directory of Open Access Journals (Sweden)

    Ricardo Silveiro Balardin

    2011-07-01

    was evaluate four seed treatments: water (T1, carbendazim + thiram (T2, fipronil + thiophanate methyl + pyraclostrobin (T3 and abamectin + thiamethoxam + fludioxonil + mefenoxan + thiabendazole (T4 on growth parameters of soybean plants with or without low water availability. The experiments were conducted under field conditions and greenhouse. In greenhouse, in treatments without low water availability, it was made four irrigations by day and in treatments with low water availability, it was made one irrigation each three days. In this trial, it was evaluated the plant height, root length, root volume, dry shoot weight, dry root weight and foliar area. In the field trial, low water availability was established by construction of low tunnels of polyethylene which prevented the water supply by irrigation and rain. In the field, it was also evaluated the plant height, the relative chlorophyll content, emergence, lesser cornstalk borer attack and grain yield. In the both environment, the plants were kept on stress until 28th days after emergence. In greenhouse, all the parameters were influenced by seed treatments with or without low water availability. In field, the treatment with fipronil + thiophanate methyl + pyraclostrobin (T3 and abamectin + thiamethoxam + fludioxonil + mefenoxan + thiabendazole (T4 promoted higher plant height and relative chlorophyll content in both hydric schemes, higher emergence and grain yield in plants without and with lower water availability, respectively. It was concluded that seed treatment with these products promote benefit changes in plant, increasing its tolerance to hydric stress, with positive effect on soybean grain yield.

  16. 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.

  17. Histological Alterations in Common Carp (Cyprinus carpio Linnaeus, 1758 Gills as Potential Biomarkers for Fungicide Contamination

    Directory of Open Access Journals (Sweden)

    Stela Stoyanova

    2015-10-01

    Full Text Available ABSTRACTThe present study aimed to investigate the histological alterations in common carp gills caused by a fosetyl-Al and fenamidone based fungicide tested in laboratory conditions at 30, 38 and 50 mg/L concentration. In general, all the tested concentrations activated compensatory-adaptive mechanisms, which caused pathological changes in the fish gills. Results showed different histological alterations in the gill structure, which included lamellar lifting, edema, proliferation of the glandular cells and epithelium, covering the gill filament, fusion and degenerative alterations. Blood circulatory system showed vasodilatation of the secondary lamellae and aneurysms. Overall, there was enhancement of the gill histological changes, which was dose-dependent, i.e., proportional to the increasing fungicide concentrations. Thus, based on the results, it was concluded that the histological alterations in common carp gills could be applied as possible biomarkers in risk assessment and monitoring programs for pesticide contamination of aquatic ecosystems.

  18. Binding characteristics of molecularly imprinted polymers based on fungicides in hydroalcoholic media.

    Science.gov (United States)

    Bitar, Manal; Bou-Maroun, Elias; Lerbret, Adrien; Ouaini, Naim; Cayot, Philippe

    2015-10-01

    An iprodione-imprinted polymer was prepared by copolymerization of methacrylamide and ethylene glycol dimethacrylate using a noncovalent imprinting approach. Methacrylamide was chosen using molecular dynamics simulations. To concentrate iprodione from hydro-alcoholic solutions, batch sorption of iprodione on the imprinted polymer were conducted. The equilibrium time for iprodione sorption is 20 min, and the corresponding kinetic mechanism follows the pseudo-second order indicating a strong interaction between iprodione and the imprinted polymer. Langmuir, Freundlich, and Dubinin-Radushkevich models were used to fit the isotherm of iprodione sorption. The imprinted polymer was found to be more efficient than the nonimprinted polymer for the uptake of iprodione, as revealed by its higher adsorption energy, affinity, and capacity. Finally, a selectivity study was conducted on the imprinted and the nonimprinted polymers to sorb three fungicides. It shows that the imprinted polymer could be used as a preconcentration phase in a multiresidue analysis of fungicides in hydroalcoholic medium.

  19. Bioconcentration and Elimination of the Dithiocarbamate Fungicide Polycarbamate in Marine Teleost Fish and Polychaete.

    Science.gov (United States)

    Hano, Takeshi; Ohkubo, Nobuyuki; Kono, Kumiko; Tanaka, Hiroyuki

    2015-09-01

    We evaluated the bioconcentration and elimination of polycarbamate, a popular antifoulant classified as a dithiocarbamate fungicide, in a marine teleost fish, mummichog (Fundulus heteroclitus), and a polychaete (Perinereis nuntia). Following polycarbamate exposure and depuration, the calculated bioconcentration factor (BCF) and elimination rate constant (k2) were 3.1 and 0.17 day(-1) in fish and 1.5-7.8 and 0.13-0.18 day(-1) in the polychaete, indicating that the fungicide has low bioconcentration potential in both organisms. Given the BCF of 3.1, the permissible environmental concentration level of polycarbamate in water was calculated to be 6.1 µg L(-1) to satisfy the threshold pesticide residue levels in fish permitted by law, which is far below the permissible levels in Hiroshima Bay, Japan. Therefore, we consider that the current polycarbamate contamination level in terms of bioconcentration is not likely to be an alarming issue in coastal environments.

  20. Enantioselective degradation of the chiral fungicides metalaxyl and furalaxyl by Brevibacillus brevis.

    Science.gov (United States)

    Sulimma, Lutz; Bullach, Anke; Kusari, Souvik; Lamshöft, Marc; Zühlke, Sebastian; Spiteller, Michael

    2013-06-01

    For almost four decades, the chiral fungicides metalaxyl and furalaxyl have been in use in plant protection on a global scale. Both substances are distributed as racemic mixtures, yet the desirable interference in nucleic acid synthesis of harmful fungi only occurs by the (-)-R-enantiomer. As enantioselective degradation in Scheyern (Germany) and Yaoundé (Cameroon) soils has been documented, the influence of 50 isolated microorganisms on the R/S ratio was investigated. A high-pressure liquid chromatography method with a chiral column to separate enantiomers of metalaxyl and furalaxyl, and subsequent detection by tandem mass spectrometry, was employed. Only one of these microorganisms, a strain of Brevibacillus brevis, showed an enantioselective degradation pattern in liquid culture; the respective (-)-R-enantiomers were preferably degraded. Moreover, (-)-R-furalaxyl was degraded faster in cultures supplemented simultaneously with both fungicides of the same concentration. © 2013 Wiley Periodicals, Inc.

  1. Efficacy of fungicides on the progress of early blight and yield of potato in Cameroon

    Directory of Open Access Journals (Sweden)

    Fontera, DA.

    1992-01-01

    Full Text Available Five fungicides were evaluated during the 1990 and 1991 growing seasons in two locations in Cameroon for efficacy on the progress of early blight and yield of potato. Disease-progress curves fitted the logistic transformation better than the Gompertz. Fungicidal treatments reduced the rate of early blight progress and area under disease-progress curve (AUDPC. Early blight was more severe in the 1991 season and yields recorded in this season were lower than those in 1990. In both seasons, high yields were obtained in plots receiving six sprays maneb or mancozeb. Two sprays of Ridomil plus (12 % metalaxyl + 60 % cuprous oxide and six of cupric hydroxide also produced appreciable yields, while fosetyl-AI (three sprays provided the least yield increase. Yield losses in non-sprayed plots were estimated at 15.7-53.6 %. Yields were negatively correlated to AUDPC.

  2. Anthracnose: A new strawberry disease in Serbia and its control by fungicides

    Directory of Open Access Journals (Sweden)

    Ivanović Mirko S.

    2007-01-01

    Full Text Available Anthracnose is a destructive disease of strawberry fruits in warm and continental climate. During 2004, in the vicinity of Valjevo, there were severe losses in two strawberry plantations due to fruit anthracnose. Two fungal isolates, GG-6A and GG-JUP were recovered from strawberry stolons and fruits showing severe anthracnose symptoms. Based on morphological and pathological characteristics, and PCR analyses with specific primers of reference species, isolate GG-6A was identified as Colletotrichum gloeosporioides, and GG-JUP isolate as C. acutatum. This is the first identification of C. acutatum in strawberry in Serbia. In order to control strawberry anthracnose, five fungicides and their combinations were applied four times during the flowering. The best fruit protection was achieved by fungicides Metiram + piraclostrobin (Cabrio top, Captan FL and Fludioksinil + ciprodinil (Swich. Less effective were Benomil (Benlate and Krezoksim-metil (Stroby. Pathogen is transmitted by planting material, so phytosanitary measures are extremely important in preventing the disease.

  3. [INFLUENCE OF FUNGICIDES COMPLEX INOCULUM EKOVITAL ON RHIZOSPHERE MICROBIOCENOSIS, DISEASES RESISTANCE AND SOYBEEN PRODUCTIVITY].

    Science.gov (United States)

    Vozniuk, S V; Tytova, L V; Lyaska, S I; Iutynska, G O

    2015-01-01

    It has been investigated the effect of fungicide with systemic action of Vitavaks 200 FF, Maxim Star 025 FS, Kinto duo and the complex inoculum Ekovital on rhizospheric microbial communities, diseases resistance and soybean productivity of Annushka biovar. The combined use of fungicides and inoculation has contributed to better formation of nodulation apparatus (the number of nodules on the roots was increased in 1.3-2.8 times), resistance increase to soybean pathogens septoriosis and ascochitosis, plant productivity increase on 17.4-32.1% relatively to the variant with Ekovital. The efficiency of the combined treatment of seeds against septoriosis and ascochitosis has become 45.8-64.1% and 82.0-95.1% respectively, in the flowering-early fruiting stage and 38.1-60.6% and 70.3-82.1% respectively, in the loading beans phase.

  4. Using Operational Weather Data to Schedule Fungicide Sprays on Tomatoes in Southern Ontario, Canada.

    Science.gov (United States)

    Gillespie, T. J.; Srivastava, B.; Pitblado, R. E.

    1993-03-01

    A fungicide-spray scheduling scheme for tomatoes called TOM-CAST (tomato forecaster) was adapted for use with operational weather data in order to increase the number of users by eliminating the need for in-field measurements of hourly temperature and leaf wetness duration. Such schemes reduce cost, environmental risk, and the development of resistance to the fungicide. Duration of wetness was estimated as the length of time that the dewpoint depression (TTd) remained between two specified limits, indicating the onset and offset of wetness. Several methods of obtaining the necessary temperature and dewpoint data were investigated. The preferred method, considering accuracy and simplicity, involved synthesis of hourly temperatures from locally observed daily maximum and minimum temperatures, and estimation of dewpoints from two Environment Canada hourly weather stations. With appropriate calibration, the scheme was able to match the number of sprays required by TOM-CAST exactly or within one spray.

  5. 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.

  6. 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.

  7. In vitro and in vivo screening of azole fungicides for antiandrogenic effects

    DEFF Research Database (Denmark)

    Taxvig, Camilla; Vinggaard, Anne; Hass, Ulla

    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...... 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...

  8. 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

    P uptake were not affected by fungicide applications apart from application of the propiconazole/fenpropimorph mixture at 100 x the recommended rate. This rate completely inhibited plant growth. AM root colonisation was reduced by the high rate of carbendazim application only. This reduction had...... no effect on plant growth which may be due to the fertile soil conditions at the field site. It is concluded that the testing for side effects of pesticides on non-target organisms should include functional parameters such as P uptake by AM fungi. Such measures may be more sensitive to harmful effects than...... 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...

  9. Modeling the interaction of the carbamate fungicide Maneb, with bovine albumin

    Science.gov (United States)

    Gomes, Victor Carvalho; Escobar, Marta Araujo Cyrino; da Costa Marques, Monica Regina; Silva, Dilson

    2016-12-01

    In the present work we modeled the interaction of Maneb (manganous ethylenebis), a carbamate fungicide, with bovine serum albumin using results from fluorescence spectroscopic measurements. Carbamates are widely used in numerous applications as pesticides and are often involved in poisonings. They are part of a large group of synthetic pesticides derived from carbamic acid esters. They have been developed and used in a large scale along the past forty years in over fifty known commercial formulations. Our results have shown that Maneb does not present fluorescence, does not form complex with albumin structure and has low quenching capacity. Furthermore only a few amount of the fungicide, near 3%, is absorbed by the bovine organism, once bound to albumin. The binding constants are 5500(±400)/M, at 37 °C, and 3100(±200) × 103 /M, at 25 °C.

  10. Fungicides, seed dresser adjuvants and storage time in the control of Drechslera teres in barley seeds

    Directory of Open Access Journals (Sweden)

    Erlei Melo Reis

    2012-09-01

    Full Text Available In experiments conducted in laboratory, the effect of fungicides, seed dresser adjuvants and storage time in the control of Drechslera teres in seeds of barley cultivar BRS Elis, with 58% incidence, was quantified. Fungicides indicated by barley research (carboxin + thiram, difenoconazole and triadimenol compared with the mixture carbendazim + iprodione were tested. As seed dresser adjuvants, water (500m mL/100 Kg and a polymer (150 mL/100 Kg were used. Treated seeds were stored in paper bags and kept in the refrigerator at 5ºC. At 30-day intervals during six months, seeds were plated on semi-selective Reis's medium (1983. The best control was obtained by the mixtures carboxin + thiram and carbendazim + iprodione and the polymer as seed dresser. The control efficiency was improved by the storage time without negatively affecting seed germination. Due to the transmission efficiency, the fungus eradication in seeds should be pursued.

  11. DNA methylation in obesity

    Directory of Open Access Journals (Sweden)

    Małgorzata Pokrywka

    2014-11-01

    Full Text Available The number of overweight and obese people is increasing at an alarming rate, especially in the developed and developing countries. Obesity is a major risk factor for diabetes, cardiovascular disease, and cancer, and in consequence for premature death. The development of obesity results from the interplay of both genetic and environmental factors, which include sedentary life style and abnormal eating habits. In the past few years a number of events accompanying obesity, affecting expression of genes which are not directly connected with the DNA base sequence (e.g. epigenetic changes, have been described. Epigenetic processes include DNA methylation, histone modifications such as acetylation, methylation, phosphorylation, ubiquitination, and sumoylation, as well as non-coding micro-RNA (miRNA synthesis. In this review, the known changes in the profile of DNA methylation as a factor affecting obesity and its complications are described.

  12. Cytochrome b gene structure and consequences for resistance to Qo inhibitor fungicides in plant pathogens.

    Science.gov (United States)

    Grasso, Valeria; Palermo, Simona; Sierotzki, Helge; Garibaldi, Angelo; Gisi, Ulrich

    2006-06-01

    The cytochrome b (cyt b) gene structure was characterized for different agronomically important plant pathogens, such as Puccinia recondita f sp tritici (Erikss) CO Johnston, P graminis f sp tritici Erikss and Hennings, P striiformis f sp tritici Erikss, P coronata f sp avenae P Syd & Syd, P hordei GH Otth, P recondita f sp secalis Roberge, P sorghi Schwein, P horiana Henn, Uromyces appendiculatus (Pers) Unger, Phakopsora pachyrhizi Syd & P Syd, Hemileia vastatrix Berk & Broome, Alternaria solani Sorauer, A alternata (Fr) Keissl and Plasmopara viticola (Berk & Curt) Berlese & de Toni. The sequenced fragment included the two hot spot regions in which mutations conferring resistance to QoI fungicides may occur. The cyt b gene structure of these pathogens was compared with that of other species from public databases, including the strobilurin-producing fungus Mycena galopoda (Pers) P Kumm, Saccharomyces cerevisiae Meyer ex Hansen, Venturia inaequalis (Cooke) Winter and Mycosphaerella fijiensis Morelet. In all rust species, as well as in A solani, resistance to QoI fungicides caused by the mutation G143A has never been reported. A type I intron was observed directly after the codon for glycine at position 143 in these species. This intron was absent in pathogens such as A alternata, Blumeria graminis (DC) Speer, Pyricularia grisea Sacc, Mycosphaerella graminicola (Fuckel) J Schröt, M fijiensis, V inaequalis and P viticola, in which resistance to QoI fungicides has occurred and the glycine is replaced by alanine at position 143 in the resistant genotype. The present authors predict that a nucleotide substitution in codon 143 would prevent splicing of the intron, leading to a deficient cytochrome b, which is lethal. As a consequence, the evolution of resistance to QoI fungicides based on G143A is not likely to evolve in pathogens carrying an intron directly after this codon.

  13. 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.

  14. Antiandrogenic effects in vitro and in vivo of the fungicide prochloraz

    DEFF Research Database (Denmark)

    Vinggaard, A.M.; Nellemann, Christine Lydia; Dalgaard, M.

    2002-01-01

    The commonly used imidazole fungicide prochloraz was tested for antiandrogenic effects in vitro and in vivo. Prochloraz, but not the metabolites 2,4,6-trichlorophenoxyacetic acid or 2,4,6-trichlorophenol, inhibited the R1881-induced response in an androgen receptor reporter gene assay. In the Her......, to the effects of flutamide. However, differential effects on levels of FSH, T-4, and TSH indicate that other modes of action apart from the pure AR antagonism might play a role in vivo....

  15. Fitness and Competitive Ability of Botrytis cinerea Isolates with Resistance to Multiple Chemical Classes of Fungicides.

    Science.gov (United States)

    Chen, S N; Luo, C X; Hu, M J; Schnabel, G

    2016-09-01

    Resistance to multiple chemical classes of fungicides in Botrytis cinerea isolates from eastern United States strawberry fields is common and strategies to control them are needed. In this study, we compared fitness and competitive ability of eight sensitive isolates (S), eight isolates resistant to five or six chemical classes of fungicides but not to phenylpyrroles (5CCR), and eight isolates resistant to six or seven chemical classes including phenylpyrroles (6CCR/MDR1h). The latter included the MDR1h phenotype due to overexpression of atrB based on Δ497V/L in mrr1. The 6CCR/MDR1h isolates grew more slowly at 4°C on potato dextrose agar, and both 5CCR and 6CCR/MDR1h isolates were hypersensitive to osmotic stress compared with S isolates. In contrast, no differences were found in oxidative sensitivity, aggressiveness, and spore production in vivo, and sclerotia production and viability in vitro. In competition experiments, the 5CCR and 6CCR/MDR1h isolates were both outcompeted by S isolates and 6CCR/MDR1h isolates were outcompeted by 5CCR isolates in the absence of fungicide pressure. Under selective pressure of a fludioxonil/pyraclostrobin rotation, the 6CCR/MDR1h isolates dominated after coinoculation with 5CCR and S isolates. The competitive disadvantage of 5CCR and especially 6CCR/MDR1h isolates suggest that, in the absence of fungicide selection pressure, S isolates may reduce inoculum potential of multifungicide-resistant isolates under field conditions.

  16. 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.

  17. Synthesis and Fungicidal Activity of 1-(Carbamoylmethyl-2-aryl-3,1-benzoxazines

    Directory of Open Access Journals (Sweden)

    Zi-Long Tang

    2017-07-01

    Full Text Available A series of new 1-(carbamoylmethyl-2-aryl-3,1-benzoxazines were prepared in moderate to good yields by BF3·OEt2-catalyzed reactions of aromatic aldehydes with 2-(N-substituted carbamoylmethylaminobenzyl alcohols. The structures of the target compounds were confirmed by IR, 1H-NMR, 13C-NMR, and elemental analyses. The fungicidal activities of the target compounds against plant fungi were preliminarily evaluated, and some of them exhibited good activity.

  18. 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.

  19. Fungicidal activity of AKWATON and in vitro assessment of its toxic effects on animal cells.

    Science.gov (United States)

    Oulé, Mathias Kégnon; Staines, Kenton; Lightly, Tasia; Roberts, Loren; Traoré, Yannick Léandre; Dickman, Michael; Bernier, Anne-Marie; Diop, Lamine

    2015-01-01

    Acquired superficial fungal infections are among the most common infections. It is necessary to create new effective and non-toxic disinfectants. AKWATON is a new disinfectant of the polymeric guanidine family. Its fungicidal activity against Trichophyton mentagrophytes and its in vitro toxicity assessment were determined in this study. The MIC, minimum fungicidal concentration (MFC) and time required for its fungicidal activity at the MFC were evaluated using the official methods of analysis of the Association of Official Analytical Chemists, with modifications as recommended by the Canadian General Standards Board. The toxic effects of AKWATON and of four commercial disinfectants were evaluated on rat pancreatic (C2C12) and muscle (RnM5F) cells, using the trypan blue and MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] methods. The MIC, MFC and time required for the fungicidal activity of AKWATON at the MFC were 0.025 % (w/v), 0.045 % (w/v) and 2.5 min, respectively. Cell cultures and the different tests carried out showed that the AKWATON-based disinfectant killed fewer cells than the commercial disinfectants, sparing 80 % of C2C12 cells and 65 % of RnM5F cells, whilst some of the well-known disinfectants currently on the market killed 85-100 % of cells. This study demonstrates that AKWATON has great potential as an odourless, colourless, non-corrosive and safe disinfectant for use in hospitals, the agriculture industry, farming and household facilities.

  20. Predictive value of cell assays for developmental toxicity and embryotoxicity of conazole fungicides.

    OpenAIRE

    Sørensen, Karin Dreisig; Taxvig, Camilla; Kjærstad, Mia Birkhøj; Nellemann, Christine Lydia; Hass, Ulla; Vinggaard, Anne Marie

    2013-01-01

    This paper evaluates in vivo predictability of a battery of in vitro tests covering developmental toxicity and embryotoxicity of five widely used conazole fungicides. The conazoles were investigated in the embryonic stem cell test, and data were compared to in vivo embryotoxicity data. The same conazoles were evaluated on the basis of data from a battery of cell assays for endocrine activity, including assays for AR, ER, AhR, and sex hormone synthesis, and data were compared to in vivo develo...

  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. Impact of Fungicides Chlorothalonil and Propiconazole on Microbial Activities in Groundnut (Arachis hypogaea L.) Soils.

    Science.gov (United States)

    Ramudu, A C; Mohiddin, G Jaffer; Srinivasulu, M; Madakka, M; Rangaswamy, V

    2011-01-01

    Introduction of agrochemicals (fungicides) into soil may have lasting effects on soil microbial activities and thus affect soil health. In order to determine the changes in microbial activity in a black clay and red sandy loam soils of groundnut (Arachis hypogaea L.) cultivated fields, a case study was conducted with propiconazole and chlorothalonil to evaluate its effects on soil enzymes (cellulase and invertase) throughout 40 days of incubation under laboratory conditions with different concentrations (1.0, 2.5, 5.0, 7.5, and 10.0 kg ha(-1)). Individual application of the two fungicides at 1.0, 2.5, and 5.0 kg ha(-1) to the soil distinctly enhanced the activities of cellulase and invertase but at higher concentrations of 7.5 and 10 kg ha(-1) was toxic or innocuous to both cellulase and invertase activities. In soil samples receiving 2.5-5.0 kg ha(-1) of the fungicides, the accumulation of reducing sugar was pronounced more at 20 days, and the activity of the cellulase and invertase was drastically decreased with increasing period of incubation up to 30 and 40 days.

  3. [Effects of bio-organic fertilizer and fungicide application on continuous cropping obstacles of cut chrysanthemum].

    Science.gov (United States)

    Chen, Xi; Zhao, Shuang; Yao, Jian-jun; Ye, Yan-ping; Song, Ai-ping; Chen, Fa-di; Chen, Su-mei; Dong, Xue-na

    2015-04-01

    Abstract: Fusarium wilt is a soil borne disease caused by plant continuous cropping in monoculture Chrysanthemum morifolium 'Youxiang' monoculture not only declines plant quality and yield but also decreases soil enzymes and soil microbial diversity over successive cultivation. In this article, the effects of fungicide (Carbendazim MBC), antifungal enhanced bio-organic fertilizer (BOF), and their combined application on the quality and soil enzymes activities of Chrysanthemum morifolium 'Youxiang' in continuous cropping systems were investigated. The results showed that both bioorganic fertilizer (BOF) and fungicide (MBC) single application could effectively prevent the occurrence of Fusarium wilt disease of cut chrysanthemum. Bio-organic fertilizer application was more effective on root activity, soil enzymes activities and quality (shoot height, stem diameter, leaf SPAD value, ray floret number, shoot fresh mass) improvement of cut chrysanthemum, while fungicide single application was responsible for soil enzymatic activities suppression to some extent. The combined application treatment (MBC+BOF) showed the best effects on quality improvement and soil enzyme activities promotion.

  4. 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.

  5. Effects of the hydrogen potential and fungicide treatment on Pitaya seed germination

    Directory of Open Access Journals (Sweden)

    Thiago Alberto Ortiz

    2014-11-01

    Full Text Available The objective of the present study was to evaluate pitaya seed germination under different hydrogen potentials, with or without fungicide treatment. A completely randomized design was employed under a 3 x 13 x 2 factorial scheme, corresponding to three pitaya species (white pitaya, pitaya hybrid I, pitaya hybrid II, thirteen hydrogen potentials (3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, and 9.0 and two fungicide conditions (presence and absence, with four replications. The percentage of germination, germination speed index and mean germination time were evaluated. The data were subjected to ANOVA, and the means were compared using the Scott-Knott test (p < 0.05. The pH influenced the germination speed index in white pitaya. The mean germination time was affected by the pH levels for white pitaya and pitaya hybrid II. The fungicide did not increase the germination percentage in the evaluated species.

  6. Occurrence of current-use fungicides and bifenthrin in Rainwater Basin wetlands.

    Science.gov (United States)

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

    2016-09-01

    Wetlands in the Rainwater Basin (RWB) of Nebraska are commonly in close proximity to or embedded within row-crop agriculture. Several fungicides and bifenthrin are applied aerially to corn throughout the RWB during tassel stage. Thus, aerial spray drift and runoff may result in pesticide contamination of wetlands. The primary objective of this study was to determine water concentrations of five fungicides and bifenthrin in wetlands located in and near fields during a heavy application period (July 16th-26th 2014) to evaluate the influence of distance from crop field on wetland contamination. In addition, the sampling sites were grouped based upon the type of water body sampled and environmental concentrations were compared to relevant "levels of concern" (LOCs) from invertebrates, fish, and amphibians selected from the literature based upon relevant toxicity data. Bifenthrin was the most frequently detected analyte, appearing in 83% of the samples. The 95th percentile concentrations across all wetlands were found to be 0.07 μg/L for bifenthrin, 0.28 μg/L for pyraclostrobin, 0.28 μg/L for azoxystrobin, and fungicides were lower than LOCs, indicating limited acute toxicity risk. However, bifenthrin concentrations were frequently higher than LOCs for aquatic arthropods. Because the water samples included particulate bound pesticides, further work is needed to determine if this bifenthrin is bioavailable and contamination levels within the sediment.

  7. Evaluation of the toxicity of fungicides to flight muscle mitochondria of bumblebee (Bombus terrestris L.).

    Science.gov (United States)

    Syromyatnikov, Mikhail Y; Kokina, Anastasia V; Lopatin, Alexey V; Starkov, Anatoly A; Popov, Vasily N

    2017-01-01

    Insects pollinate 75% of crops used for human consumption. Over the last decade, a substantial reduction in the abundance of pollinating insects has been recorded and recognized as a severe matter for food supply security. Many of the important food crops destined for human consumption are grown in greenhouses. A unique feature of greenhouse agriculture is the extensive use of fungicides to curb multiple fungal infections. The most widely used pollinating insects in greenhouses are commercially reared bumblebees. However, there is no data regarding the toxicity of fungicides to bumblebee mitochondria. To fill this gap in knowledge, we examined the effects of 16 widely used fungicides on the energetics of the flight muscles mitochondria of Bombus terrestris. We found that diniconazole and fludioxonil uncoupled the respiration of mitochondria; dithianon and difenoconazole inhibited it. By analyzing the action of these inhibitors on mitochondrial respiration and generation of reactive oxygen species, we concluded that difenoconazole inhibited electron transport at the level of Complex I and glycerol-3-phosphate dehydrogenase. Dithianon strongly inhibited succinate dehydrogenase and glycerol-3-phosphate dehydrogenase. It also strongly inhibited mitochondrial oxidation of NAD-linked substrates or glycerol 3-phosphate, but it had no effect on the enzymatic activity of Complex I. It may be suggested that dithianon inhibits electron transport downstream of Complex I, likely at multiply sites.

  8. 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.

  9. Triazole fungicides and the selection of resistance to medical triazoles in the opportunistic mould Aspergillus fumigatus.

    Science.gov (United States)

    Verweij, Paul E; Kema, Gert H J; Zwaan, Bas; Melchers, Willem J G

    2013-02-01

    Azole resistance is an emerging problem in the opportunistic mould Aspergillus fumigatus. The triazoles are the most important agents for the management of Aspergillus diseases in humans. Selection for acquired resistance may occur in the hospital setting through exposure to high doses of azoles during azole therapy, but evidence is accumulating that A. fumigatus may become resistant to medical triazoles through environmental exposure to fungicides. The recovery of A. fumigatus isolates resistant to the medical triazoles from azole-naive patients as well as from the environment strongly indicates an environmental route of resistance selection. Molecule alignment studies have identified five fungicides that share a very similar molecule structure with the medical triazoles, and thus may have selected for mechanisms that confer resistance to both groups of compounds. It is important to explore further the presumed fungicide-driven route of resistance selection in order to implement effective preventive measures as the prevalence of azole resistance in A. fumigatus continues to increase and causes major challenges in the management of azole-resistant Aspergillus diseases.

  10. 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.

  11. 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.

  12. Modeling fungicides mobility in undisturbed vineyard soil cores unamended and amended with spent mushroom substrates.

    Science.gov (United States)

    Marín-Benito, Jesús María; Rodríguez-Cruz, María Sonia; Sánchez-Martín, María Jesús; Mamy, Laure

    2015-09-01

    The performance of the pesticide fate model PRZM to predict the fate of two fungicides, penconazole and metalaxyl, and the major metabolite of metalaxyl (CGA-62826), in amended and unamended vineyard soils was tested from undisturbed soils columns experiments. Three different treatments were tested in two soils: control soil (unamended), and soil amended with fresh or composted spent mushroom substrates, which correspond to common agricultural practices in Spain. Leaching experiments were performed under non-saturated flow conditions. The model was parameterized with laboratory and literature data, and using pedotransfer functions. It was first calibrated for water flow against chloride breakthrough curves. The key parameter was the hydrodynamic dispersion coefficient (DISP). No leaching of penconazole, the most hydrophobic fungicide, was observed. It remained in the top 0-8 cm of the column. In any case, simulations were highly correlated to the experimental results. On the contrary, metalaxyl and its metabolite were consistently found in the leachates. A calibration step of the Kd of metalaxyl and CGA-62826 and of DISP for CGA-62826 was necessary to obtain good prediction of the leaching of both compounds. PRZM generally simulated acceptable metalaxyl vertical distribution in the soil profiles although results were overestimated for its metabolite. Nevertheless, PRZM can be reasonably used to assess the leaching (through breakthrough curves) and vertical distribution of fungicides in amended soils, knowing their DISP values. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Antifungal effectiveness of fungicide and peroxyacetic acid mixture on the growth of Botrytis cinerea.

    Science.gov (United States)

    Ayoub, Fatima; Ben Oujji, Najwa; Chebli, Bouchra; Ayoub, Mohamed; Hafidi, Athman; Salghi, Rachid; Jodeh, Shehdeh

    2017-04-01

    In the attempt to reduce the negative impacts of chemical pesticides on environment and consumer's health, a new plant treatment practice minimizing the amount of pesticides needed during pests and diseases treatments has been developed. Our approach is based on combining the biocide effects of fungicide with the peroxyacetic acid (PAA) one. In this paper, we focused on the in vitro study of the antifungal activity of this combination against Botrytis cinerea, the most redoubtable threat of tomatoes plants in Morocco. First, different concentrations of a peroxyacetic acid product (PERACLEAN(®)5) and two commercially available fungicides SWITCH and SIGNUM were tested separately for their inhibitory effects on the mycelial growth and spores germination of B. cinerea. 100% inhibition of fungal growth was achieved using 16.77 and 14.47 μg/ml of SIGNUM and SWITCH respectively and 1.5% of PERACLEAN(®)5. When combined with 0.5% of the peroxyacetic acid mixture (PERACLEAN(®)5), the pesticides 100% effective concentrations decreased to 0.5 μg/ml for both pesticides. Hence, this approach allowed us to suppress the pathogen while minimizing the amounts of applied fungicides by more than 95%. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Enantioselective bioactivity, acute toxicity and dissipation in vegetables of the chiral triazole fungicide flutriafol.

    Science.gov (United States)

    Zhang, Qing; Hua, Xiu-de; Shi, Hai-yan; Liu, Ji-song; Tian, Ming-ming; Wang, Ming-hua

    2015-03-02

    The enantioselective bioactivity, acute toxicity and stereoselective degradation of the chiral triazole fungicide flutriafol in vegetables were investigated for the first time using the (R)-, (S)- and rac-flutriafol. The order of the bioactivity against five target pathogens (Rhizoctonia solani, Alternaria solani, Pyricularia grisea, Gibberella zeae, Botrytis cinerea) was found to be (R)-flutriafol>rac-flutriafol>(S)-flutriafol. The fungicidal activity of (R)-flutriafol was 1.49-6.23 times higher than that of (S)-flutriafol. The (R)-flutriafol also showed 2.17-3.52 times higher acute toxicity to Eisenia fetida and Scenedesmus obliquus than (S)-flutriafol. The stereoselective degradation of flutriafol in tomato showed that the active (R)-flutriafol degraded faster, resulting in an enrichment of inactive (S)-form, and the half-lives were 9.23 d and 10.18 d, respectively. Inversely, the (S)-flutriafol, with a half-life of 4.76 d, was preferentially degraded in cucumber. In conclusion, the systemic assessments of the triazole fungicide flutriafol stereoisomers on the enantioselective bioactivity, acute toxicity and environmental behavior may have implications for better environmental and ecological risk assessment. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Target-orientated and precise, real-time fungicide application in cereals

    Directory of Open Access Journals (Sweden)

    Karl-Heinz Dammer

    2015-04-01

    Full Text Available Real-time application technologies based on the target crop, crop surface area and biomass using non-contact sensors for precise fungicide spraying in winter wheat have been developed in a joint research project. The decision support system proPlant expert.classic and the internet-version proPlant expert.com (proPlant GmbH suggest appropriate fungicides and dosages for certain infection scenarios of eight important leaf and ear diseases of winter wheat. The Precision Farming Module “Fungicide”, which runs on the on-board terminal in the tractor cabin, controls the spraying process. During the spraying process, the module defines the local target application amount using a local ultrasonic sensor value as an input parameter.Winter wheat field experiments were conducted in 2013 and 2014 (Agri Con Co., ATB to analyse the relationship between the sensor values (ultrasonic and camera and the leaf area index (LAI and biomass crop parameters that are important for a locally adapted and variable fungicide application rate. Measurements were performed several times during the vegetation period at sampling points that were visually selected based on crop density. Regression analyses showed that after technical changes in 2014, a linear relationship was obtained between the sensor values and the two crop parameters.

  16. 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.

  17. 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.

  18. Apoptosis and DNA Methylation

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Huan X.; Hackett, James A. [MRC Human Genetics Unit, IGMM, Western General Hospital, Edinburgh EH4 2XU (United Kingdom); Nestor, Colm [MRC Human Genetics Unit, IGMM, Western General Hospital, Edinburgh EH4 2XU (United Kingdom); Breakthrough Research Unit, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU (United Kingdom); Dunican, Donncha S.; Madej, Monika; Reddington, James P. [MRC Human Genetics Unit, IGMM, Western General Hospital, Edinburgh EH4 2XU (United Kingdom); Pennings, Sari [Queen' s Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ (United Kingdom); Harrison, David J. [Breakthrough Research Unit, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU (United Kingdom); Meehan, Richard R., E-mail: Richard.Meehan@hgu.mrc.ac.uk [MRC Human Genetics Unit, IGMM, Western General Hospital, Edinburgh EH4 2XU (United Kingdom); Breakthrough Research Unit, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU (United Kingdom)

    2011-04-01

    Epigenetic mechanisms assist in maintaining gene expression patterns and cellular properties in developing and adult tissues. The molecular pathology of disease states frequently includes perturbation of DNA and histone methylation patterns, which can activate apoptotic pathways associated with maintenance of genome integrity. This perspective focuses on the pathways linking DNA methyltransferases and methyl-CpG binding proteins to apoptosis, and includes new bioinformatic analyses to characterize the evolutionary origin of two G/T mismatch-specific thymine DNA glycosylases, MBD4 and TDG.

  19. Apoptosis and DNA Methylation

    Directory of Open Access Journals (Sweden)

    Richard R. Meehan

    2011-04-01

    Full Text Available Epigenetic mechanisms assist in maintaining gene expression patterns and cellular properties in developing and adult tissues. The molecular pathology of disease states frequently includes perturbation of DNA and histone methylation patterns, which can activate apoptotic pathways associated with maintenance of genome integrity. This perspective focuses on the pathways linking DNA methyltransferases and methyl-CpG binding proteins to apoptosis, and includes new bioinformatic analyses to characterize the evolutionary origin of two G/T mismatch-specific thymine DNA glycosylases, MBD4 and TDG.

  20. Interactions between crop biomass and development of foliar diseases in winter wheat and the potential to graduate the fungicide dose according to crop biomass

    DEFF Research Database (Denmark)

    Jensen, Peter Kryger; Jørgensen, Lise Nistrup

    2016-01-01

    is typically carried out using a constant fungicide dose in the entire field although there may be large differences in crop development and biomass across the field. The objective of the study reported in this paper was to test whether the fungicide dose response curve controlling septoria leaf blotch...... and other foliar diseases in winter wheat was dependent on crop development and biomass level. If such a biomass dependent dose response was found it was further the purpose to evaluate the potential to optimize fungicide inputs in winter wheat crops applying a site-specific crop density dependent fungicide...... dose. The study was carried out investigating fungicide dose response controlling foliar diseases in winter wheat at three biomass densities obtained growing the crop at three nitrogen levels and using variable seed rates. Further the field experiments included three fungicide dose rates at each...

  1. Metabolic effects of azoxystrobin and kresoxim-methyl against Fusarium kyushuense examined using the Biolog FF MicroPlate.

    Science.gov (United States)

    Wang, Hancheng; Wang, Jin; Chen, Qingyuan; Wang, Maosheng; Hsiang, Tom; Shang, Shenghua; Yu, Zhihe

    2016-06-01

    Azoxystrobin and kresoxim-methyl are strobilurin fungicides, and are effective in controlling many plant diseases, including Fusarium wilt. The mode of action of this kind of chemical is inhibition of respiration. This research investigated the sensitivities of Fusarium kyushuense to azoxystrobin and kresoxim-methyl, and to the alternative oxidase inhibitor salicylhydroxamic acid (SHAM). The Biolog FF MicroPlate is designed to examine substrate utilization and metabolic profiling of micro-organisms, and was used here to study the activity of azoxystrobin, kresoxim-methyl and SHAM against F. kyushuense. Results presented that azoxystrobin and kresoxim-methyl strongly inhibited conidial germination and mycelial growth of F. kyushuense, with EC50 values of 1.60 and 1.79μgml(-1), and 6.25 and 11.43μgml(-1), respectively; while not for SHAM. In the absence of fungicide, F. kyushuense was able to metabolize 91.6% of the tested carbon substrates, including 69 effectively and 18 moderately. SHAM did not inhibit carbon substrate utilization. Under the selective pressure of azoxystrobin and kresoxim-methyl during mycelial growth (up to 100μgml(-1)) and conidial germination (up to 10μgml(-1)), F. kyushuense was unable to metabolize many substrates in the Biolog FF MicroPlate; while especially for carbon substrates in glycolysis and tricarboxylic acid cycle, with notable exceptions such as β-hydroxybutyric acid, y-hydroxybutyric acid, α-ketoglutaric acid, α-d-glucose-1-phosphate, d-saccharic acid and succinic acid in the mycelial growth stage, and β-hydroxybutyric acid, y-hydroxybutyric acid, α-ketoglutaric acid, tween-80, arbutin, dextrin, glycerol and glycogen in the conidial germination stage. This is a new finding for some effect of azoxystrobin and kresoxim-methyl on carbon substrate utilization related to glycolysis and tricarboxylic acid cycle and other carbons, and may lead to future applications of Biolog FF MicroPlate for metabolic effects of other

  2. 融合群水平上的棉花立枯病防病用药筛选%The Fungicide Screening Used for Controlling Cotton Seedling Damping -off Based on the Level of Anastomosis Group

    Institute of Scientific and Technical Information of China (English)

    张燕南; 郭庆元; 毕司进; 赵燕

    2015-01-01

    【目的】棉花立枯病是影响新疆棉花产量和质量的重要病害,筛选高效防病药剂,有效控制该病的发生为害。【方法】采用分属不同融合群的立枯丝核菌菌株作为供试菌,通过抑菌圈实验﹑毒力测定和田间防效验证,对多种立枯病防病用药进行比较和筛选。【结果】12种药剂对棉花立枯丝核菌主要融合群(AG4)的抑制作用有明显差异,12种药剂中,甲基立枯磷﹑GJJ﹑ BL﹑卫福﹑代森锰锌﹑百菌清等8种药剂抑菌作用较好;9种农药对立枯丝核菌的毒力大小差异显著,同一种农药对不同融合群的毒力亦有一定差异,4种农药中对立枯丝核菌总的毒力及对棉花立枯病菌主要融合群的毒力较大,EC50﹤3 mg∕L 的药剂有 GJJ﹑甲基立枯磷﹑BL﹑卫福;4种药剂的田间防病效果在大田最高防效达65%以上。【结论】12种药剂中 4种药剂(GJJ﹑甲基立枯磷﹑卫福﹑BL)对棉花立枯病有较好的防效;GJJ﹑甲基立枯磷对棉花立枯病表现出高效防病作用。%Objective]Cotton damping —off is an important disease affecting the yield and quality of cot_ton in Xinjiang.This project aims to efficiently screen prophylactic fungicide which might effectively protect the disease from occurrence and damage.[Method] The strains of Rhizoctonia belonging to different anasto_mosis groups were taken as the test bacteria,and through inhibition zone test,toxicity test and checking in the fields,a variety of pesticide that prevent Rhizoctonia solani KÜhn was compared and contrasted before making final choice.[Result]The inhibition zone test indicated that: among the 12 kinds of fungicides,the inhibitory effect which could fight against the major anastomosis group (AG4) of cotton Rhizoctonia solani had significant differences;Among them,8 kinds of fungicide such as tolclofos —methyl GJJ,BL and Thiram ﹠Carboxin etc. had better inhibitory effect.Toxicity test results showed that

  3. Methylated β-Cyclodextrins

    DEFF Research Database (Denmark)

    Schönbeck, Jens Christian Sidney; Westh, Peter; Madsen, Jens Christian

    2011-01-01

    groups at O2 promote complexation by extending the hydrophobic cavity. Like in the case of 2-hydroxypropylated cyclodextrins, the methyl substituents cause an increased release of ordered water from the hydration shell of the bile salts, resulting in a strong increase in both the enthalpy and the entropy...

  4. Methylated β-Cyclodextrins

    DEFF Research Database (Denmark)

    Schönbeck, Jens Christian Sidney; Westh, Peter; Madsen, Jens Christian

    2011-01-01

    groups at O2 promote complexation by extending the hydrophobic cavity. Like in the case of 2-hydroxypropylated cyclodextrins, the methyl substituents cause an increased release of ordered water from the hydration shell of the bile salts, resulting in a strong increase in both the enthalpy and the entropy...

  5. 几种化学杀菌剂对苹果轮纹病的药效评价%Evaluation on the effects of several chemical fungicides for control of Botryosphaeria dothidea

    Institute of Scientific and Technical Information of China (English)

    李娜; 刘丽; 曹克强

    2009-01-01

    为解决当前苹果轮纹病对传统药剂产生抗性问题,以70%代森锰锌可湿性粉剂为对照,在室内测试了10%苯醚甲环唑水分散粒剂.250g·L~(-1)嘧菌酯悬浮剂等6种化学杀菌剂的室内毒力;另外在田问设置小区试验,测定了这些药剂在不同使用质量浓度条件下对苹果轮纹病的防治效果.结果表明,除50%醚菌酯水分散粒剂以外,其他几种化学药剂均表现出优于70%代森锰锌的抑菌和防病效果.在室内测试中.10%的苯醚甲环唑水分散粒剂表现出最高的毒力,EC_50为0.017mg·L~(-1);250 g·L~(-1)嘧菌酯悬浮剂800倍浓度在田问测试中表现出最好的防病效果,采收期防效达92.39%:贮藏15 d和30d防效分别达到100%和98.59%.该试验结果为部分新药剂的产品登记以及为生产上选择适于防治苹果轮纹病的药剂种类提供了依据.%In order to solve the problem of Botryosphaeria dothidea on resistance to traditional fungicides,bio-assay tests were made for 6 fungicides including 10% water-dispersible granules of difenoconazole, 250 g·L~(-1)azoxystrobin suspension concentrate etc.against B.dothidea in laboratory.Field tests of these fungicides with different concentrations were made for control of the disease on apple trees.The results showed that except water-dispersible granules of 50% kresoxim-methyl, the other fungicides expressed stronger inhibitory effects against mycelium growth than that of 70% mancozeb wettable powder.10% difenoconazole water dispersible granules showed the highest toxicity with ECho of 0.017 mg L~-1 In the field tests,250 g· L~(-1) azoxystrobin suspension concentrate at the concentration of 800 times concentration was the best one for control of this disease at harvest stage, with effectiveness of 92.39% ; and after stored for 15 and 30 d effectiveness reached 100% and 98.59%.These tests provided a sound basis for fungicide registration and for choice of suitable fungicides for control of B

  6. Studies on the cost-effective management of Alternaria blight of rapeseed-mustard (Brassica spp.

    Directory of Open Access Journals (Sweden)

    M.M. Khan

    2007-08-01

    Full Text Available Three systemic fungicides: Topsin-M (Thiophanate methyl, 70%WP, Ridomil MZ (Mancozeb, 64% + Metalaxyl, 8%WP, and Bavistin (Carbendazim, 50%WP alone and in combination with four non-systemic fungicides Captaf (Captan, 50%WP, Indofil M-45 (Mancozeb, 75%WP, Indofil Z-78 (Zineb, 75%WP, and Thiram (Thiram, 75%WP were evaluated both in vitro and in vivo for their effectiveness to manage Alternaria blight of rapeseedmustard caused by Alternaria brassicae. A pure culture of the pathogenic fungus was applied in the field at 2 g colonized sorghum seeds kg-1 soil. All the fungicides were evaluated for their efficacy at various concentrations, 50, 100, 150, 200 and 500 ppm, and were sprayed in the field at 0.2% a.i. l-1. All fungicides significantly reduced the severity of the disease but Ridomil MZ was most effective. Topsin-M at a concentration of 500 ppm was the most effective in reducing radial growth of the pathogenic fungi (74.2%. Ridomil MZ reduced disease severity by 32% and was followed in effectiveness by the combination Bavistin+Captaf (26.5%. Maximum yield was obtained in plots sprayed with Bavistin+Captaf (1198 kg ha-1 followed by Bavistin+Indofil Z-78 (1172 kg ha-1. It was worth noting that the highest net profit as well as the highest cost-benefit ratio was obtained with Bavistin+Indofil Z-78 (1:3.2, followed by Bavistin+Captaf (1:1.3.

  7. Waterborne toxicity and diet-related effects of fungicides in the key leaf shredder Gammarus fossarum (Crustacea: Amphipoda).

    Science.gov (United States)

    Zubrod, J P; Englert, D; Wolfram, J; Wallace, D; Schnetzer, N; Baudy, P; Konschak, M; Schulz, R; Bundschuh, M

    2015-12-01

    Animals involved in leaf litter breakdown (i.e., shredders) play a central role in detritus-based stream food webs, while their fitness and functioning can be impaired by anthropogenic stressors. Particularly fungicides can affect shredders via both waterborne exposure and their diet, namely due to co-ingestion of adsorbed fungicides and shifts in the leaf-associated fungal community, on which shredders' nutrition heavily relies. To understand the relevance of these effect pathways, we used a full 2×2-factorial test design: the leaf material serving as food was microbially colonized for 12 days either in a fungicide-free control or exposed to a mixture of five current-use fungicides (sum concentration of 62.5μg/L). Similarly, the amphipod shredder Gammarus fossarum was subjected to the same treatments but for 24 days. Waterborne exposure reduced leaf consumption by ∼20%, which did not fully explain the reduction in feces production (∼30%), indicating an enhanced utilization of food to compensate for detoxification mechanisms. This may also explain the reduced feces production (∼10%) of gammarids feeding on fungicide-exposed leaves. The reduction may, however, also be caused by a decreased nutritious quality of the leaves indicated by a reduced species richness (∼40%) of leaf-associated fungi. However, compensation for these effects by Gammarus was seemingly incomplete, since both waterborne exposure and the consumption of the fungicide-affected diet drastically reduced gammarid growth (∼110% and ∼40%, respectively). Our results thus indicate that fungicide mixtures have the potential for detrimental implications in aquatic ecosystem functioning by affecting shredders via both effect pathways.

  8. Effects of the boscalid fungicide Filan® on the marine amphipod Allorchestes compressa at environmentally relevant concentrations.

    Science.gov (United States)

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

    2016-05-01

    Fungicides are widely used in agriculture to control fungal diseases. After application, fungicides can be transported offsite to surface and groundwater and ultimately enter estuarine and marine environments. The presence of fungicides in the marine environment may pose risks to marine organisms, but little is known about fungicide effects on these organisms, especially invertebrates. The present study investigated the effects of the commonly used boscalid fungicide Filan® on life history traits, feeding rate, and energy reserves (lipid, glycogen, and protein content) of the marine amphipod Allorchestes compressa over 6 wk under laboratory conditions. Amphipods were exposed to 3 concentrations of Filan (1 μg, 10 μg, and 40 μg active ingredient [a.i.]/L), with 5 replicates per treatment. Lipid content and reproduction were the most sensitive measures of effect, with lipid content reduced by 53.8% at the highest concentration. Survival, growth, and other energy reserves of amphipods were also negatively affected by Filan, and the effects were concentration dependent. Antennal deformities were incidentally observed on the amphipods at a concentration of 40 μg a.i./L. The results of the present study indicate comprehensive effects of the boscalid fungicide Filan on A. compressa at environmentally relevant concentrations. The decline or absence of A. compressa in marine ecosystems could impair the ecosystem function because of their important role in trophic transfer and nutrient recycling. The authors' results suggest that even though the use of fungicides is often regarded as posing only a minor risk to aquatic organisms, the assessment of their long-term effects is critical.

  9. Ionic liquid-based ultrasound-assisted emulsification microextraction coupled with high performance liquid chromatography for the determination of four fungicides in environmental water samples.

    Science.gov (United States)

    Liang, Pei; Wang, Fang; Wan, Qin

    2013-02-15

    A highly efficient and environmentally friendly sample preparation method termed ionic liquid-based ultrasound-assisted emulsification microextraction (IL-USAEME) combined with high performance liquid chromatography has been developed for the determination of four fungicides (azoxystrobin, diethofencarb, pyrimethanil and kresoxim-methyl) in water samples. In this novel approach, ionic liquid (IL) was used as extraction solvent in place of the organic solvent used in conventional USAEME assay, and there is no need for using organic dispersive solvent which is typically required in the common dispersive liquid-liquid microextraction method. Various parameters that affect the extraction efficiency, such as the kind and volume of IL, ultrasound emulsification time, extraction temperature and salt addition were investigated and optimized. Under the optimum extraction condition, the linearities of calibration curves were in the range from 3 to 5000 ng mL(-1) for target analytes with the correlation coefficient higher than 0.9992. The enrichment factors and the limits of detection were in the range of 88-137 and 0.73-2.2 ng mL(-1), depending on the analytes. The environmental water samples were successfully analyzed using the proposed method, and the relative recoveries at fortified levels of 50 and 100 ng mL(-1) were in the range of 83.9%-116.2%.

  10. Control Effect of Different Fungicides to Powdery Mildew of Jatropha curcas%不同药剂对麻疯树白粉病的防治效果研究

    Institute of Scientific and Technical Information of China (English)

    郑少华

    2014-01-01

    Four highly effective and lowly toxic fungicides (including 70% of methyl topsin wettable powder ,50% of daconil suspending agent ,5% of hexaconazole microemulsion and 15% of triadimefon wettable powder)were used in plot trials and the results show that all of them are effective to the control of powdery mildew and among them ,the best effective fungicides is 70% of methyl topsin with 800 times of water and the controlling effect reaches 88 .89%after spraying 3 times ,which had remarkable and lasting effect ,and the control effect was superior to others .The controlling effect of tow concentration chemicals can be strengthened obviously by increasing spraying times ,there-fore ,it is suggested that low concentration chemicals should be sprayed continuuously 2 ~ 3 times ,which can delay the resistance of powdery mildew to fungicides .%选用日曹-甲基托布津70%可湿性粉剂、百菌清50%悬浮剂、云大翠丽5%己唑醇微乳剂和粉锈宁15%可湿性粉剂等4种高效低毒的农药对麻疯树白粉病进行大田药效试验,结果表明:4种药剂对麻疯树白粉病均具有显著的防治效果,其中以日曹-甲基托布津70%可湿性粉剂稀释800倍液的防治效果最好,3次施药后防治效果达88.89%,对麻疯树白粉病的防治效果显著且稳定,优于其他药剂;喷洒次数的增加可明显提高低浓度杀菌剂的防治效果,因此生产上应尽量使用低浓度药剂连续喷洒2~3次,可延缓麻疯树白粉病抗药性的产生。

  11. Reaction of Ketene Dithioacetals with Pyrazolylcarbohydrazide:Synthesis and Biological Activities of Ethyl 5-Amino-1-(5'-methyl-1'-t-butyl-4'-pyrazolyl)carbonyl-3-methylthio-1H-pyrazole-4-carboxylate

    Institute of Scientific and Technical Information of China (English)

    LI Ming李明; WEN Li-Rong文丽荣; FU Wei-Jun付维军; ZHAO Gui-Long赵桂龙; HU Fang-Zhong胡方中; YANG Hua-Zheng杨华铮

    2004-01-01

    The title compound, C16-H23N5O3S, ethyl 5-amino-1-(5'-methyl-1'-t-butyl-4'-pyrazolyl)carbonyl-3-methylthio1H-pyrazole-4-carboxylate (5) has been synthesized by the treatment of ethyl 2-cyano-3,3-dimethylthioacrylate with 1-t-butyl-5-methyl-4-hydrazinocarbonylpyrazole (4) in refluxed ethanol. The possible mechanism of the above reaction was also discussed. The results of biological test show that the title compound has fungicidal and plant growth regulation activities.

  12. 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)

  13. 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.

  14. Occurrence of mycotoxins in wheat grains exposed to fungicides on fusarium head blight control in southern Brazil.

    Science.gov (United States)

    Marques, Leandro N; Pizzutti, Ionara R; Balardin, Ricardo S; Dos Santos, Ingrid D; Dias, Jonatan V; Stefanello, Marlon T; Serafini, Pablo T

    2017-01-12

    Mycotoxins occurrence in wheat grains impose risks to human and animal health. The southern Brazil has favorable weather conditions for Fusarium graminearum infections and consequently for mycotoxins accumulation on grains. The goal of this study was to evaluate the behavior of new wheat commercial genotypes to Fusarium Head Blight (FHB), to control performance of new fungicide formulations and their relationship with mycotoxins concentration in grains. The manly mycotoxin occurrence on wheat grains in southern Brazil was deoxynivalenol (DON). Two cultivars showed high DON concentration above the tolerance limits (>3000 μg kg(-1)). Many other mycotoxins monitored presented concentrations below method detection limit. Satisfactory levels of fungicide effectiveness were achieved against F. graminearum. Some fungicides promoted a satisfactory decrease on DON accumulation in grains. The best results were obtained when prothioconazole was present. SDHI (Succinate dehydrogenase inhibitors) + QoI (Quinone outside inhibitors) fungicides showed benefic effects at FHB control at field, but it did not promote satisfactory reduction on DON contamination. Fungicides can be used satisfactory for FHB control and reduce DON contamination in grains in southern Brazil. The presence of prothioconazole should be recommended. Some genotypes showed high DON concentration and it was not directly related with FHB severity at field.

  15. Development Status and Prospect of Agricultural Fungicide%农用杀菌剂发展现状及展望

    Institute of Scientific and Technical Information of China (English)

    陶燕

    2014-01-01

    Agriculture was one of the largest field where the most amount and kinds of fungicide were used. Agricultural fungicide referred to a class of pesticides for control of plant diseases caused by a variety of pathogenic microorganisms, which can kill the pathogen spores, mycelium or inhibit the growth.The structure and biological activity of agricultural fungicide were summarized, such as triazole, pyridines, imidazole fungicides and so on.The prospect of the research direction in the development of fungicides was look forward.%农业是杀菌剂使用量最大,所用品种最多,使用范围最广的一个领域。农用杀菌剂是指用于防治由各种病原微生物引起的植物病害的一类农药,一般指杀真菌剂,具有杀死病菌孢子、菌丝体或者抑制其发育、生长的作用。文章综述了三唑类、吡啶类、噁(咪)唑类等农用杀菌剂的结构及其生物活性,并展望了今后杀菌剂开发的研究方向。

  16. Probing the molecular interaction of triazole fungicides with human serum albumin by multispectroscopic techniques and molecular modeling.

    Science.gov (United States)

    Zhang, Jing; Zhuang, Shulin; Tong, Changlun; Liu, Weiping

    2013-07-31

    Triazole fungicides, one category of broad-spectrum fungicides, are widely applied in agriculture and medicine. The extensive use leads to many residues and casts potential detrimental effects on aquatic ecosystems and human health. After exposure of the human body, triazole fungicides may penetrate into the bloodstream and interact with plasma proteins. Whether they could have an impact on the structure and function of proteins is still poorly understood. By using multispectroscopic techniques and molecular modeling, the interaction of several typical triazole fungicides with human serum albumin (HSA), the major plasma protein, was investigated. The steady-state and time-resolved fluorescence spectra manifested that static type, due to complex formation, was the dominant mechanism for fluorescence quenching. Structurally related binding modes speculated by thermodynamic parameters agreed with the prediction of molecular modeling. For triadimefon, hydrogen bonding with Arg-218 and Arg-222 played an important role, whereas for imazalil, myclobutanil, and penconazole, the binding process was mainly contributed by hydrophobic and electrostatic interactions. Via alterations in three-dimensional fluorescence and circular dichroism spectral properties, it was concluded that triazoles could induce slight conformational and some microenvironmental changes of HSA. It is anticipated that these data can provide some information for possible toxicity risk of triazole fungicides to human health and be helpful in reinforcing the supervision of food safety.

  17. Microscopy reveals disease control through novel effects on fungal development: a case study with an early-generation benzophenone fungicide.

    Science.gov (United States)

    Schmitt, Mark R; Carzaniga, Raffaella; Cotter, H Van T; O'Connell, Richard; Hollomon, Derek

    2006-05-01

    The benzophenones are a new class of agricultural fungicides that demonstrate protectant, curative and eradicative/antisporulant activity against powdery mildews. The chemistry is represented in the marketplace by the fungicide metrafenone, recently introduced by BASF and discussed in the following paper. The benzophenones show no evidence of acting by previously identified biochemical mechanisms, nor do they show cross-resistance with existing fungicides. The value of microscopy in elucidating fungicide mode of action is demonstrated through identification of the effects of an early benzophenone, eBZO, on mildew development. eBZO caused profound alterations in the morphology of powdery mildews of both monocotyledons and dicotyledons, affecting multiple stages of fungal development, including spore germination, appressorial formation, penetration, surface hyphal morphology and sporogenesis. Identification of analogous effects of eBZO on sporulation in the model organism Aspergillus nidulans (Eidam) Winter provides a unique opportunity to elucidate important morphogenetic regulatory sites in the economically important obligate pathogens, the powdery mildews. Benzophenones provide a further example of the benefits of whole-organism testing in the search for novel fungicide modes of action. Copyright 2006 Society of Chemical Industry.

  18. Synthesis and biological evaluation of novel fluorine-containing stilbene derivatives as fungicidal agents against phytopathogenic fungi.

    Science.gov (United States)

    Jian, Weilin; He, Daohang; Xi, Pinggen; Li, Xinwei

    2015-11-18

    The rising development of resistance to conventional fungicides is driving the search for new alternative candidates to control plant diseases. In this study, a series of new fluorine-containing stilbene derivatives was synthesized on the basis of our previous quantitative structure-activity relationship analysis results. Bioassays in vivo revealed that the title compounds exhibited potent fungicidal activities against phytopathogenic fungi (Colletotrichum lagenarium and Pseudoperonospora cubensis) from cucumber plants. In comparison to the previous results, the introduction of a fluorine moiety showed improved activities of some compounds against those fungi. Notably, compound 9 exhibited a control efficacy against C. lagenarium (83.4 ± 1.3%) comparable to that of commercial fungicide (82.7 ± 1.7%). For further understanding the possible mode of action of the stilbene against C. lagenarium, the effects on hyphal morphology, electrolyte leakage, and respiration of mycelial cell suspension were studied. Microscopic observation showed considerably deformed mycelial morphology. The conductivity of mycelial suspension increased in the presence of compound 9, whereas no significantly inhibitory effect on respiration was observed. Taken together, the fungicidal mechanism of this stilbene is associated with its membrane disruption effect, resulting in increased membrane permeability. These results provide important clues for mechanistic study and derivatization of stilbenes as alternative sources of fungicidal agents for plant disease control.

  19. Fungicide efflux and the MgMFS1 transporter contribute to the multidrug resistance phenotype in Zymoseptoria tritici field isolates.

    Science.gov (United States)

    Omrane, Selim; Sghyer, Hind; Audéon, Colette; Lanen, Catherine; Duplaix, Clémentine; Walker, Anne-Sophie; Fillinger, Sabine

    2015-08-01

    Septoria leaf blotch is mainly controlled by fungicides. Zymoseptoria tritici, which is responsible for this disease, displays strong adaptive capacity to fungicide challenge. It developed resistance to most fungicides due to target site modifications. Recently, isolated strains showed cross-resistance to fungicides with unrelated modes of action, suggesting a resistance mechanism known as multidrug resistance (MDR). We show enhanced prochloraz efflux, sensitive to the modulators amitryptiline and chlorpromazine, for two Z. tritici strains, displaying an MDR phenotype in addition to the genotypes CYP51(I381V Y461H) or CYP51(I381V ΔY459/) (G460) , respectively, hereafter named MDR6 and MDR7. Efflux was also inhibited by verapamil in the MDR7 strain. RNA sequencing lead to the identification of several transporter genes overexpressed in both MDR strains. The expression of the MgMFS1 gene was the strongest and constitutively high in MDR field strains. Its inactivation in the MDR6 strain abolished resistance to fungicides with different modes of action supporting its involvement in MDR in Z. tritici. A 519 bp insert in the MgMFS1 promoter was detected in half of the tested MDR field strains, but absent from sensitive field strains, suggesting that the insert is correlated with the observed MDR phenotype. Besides MgMfs1, other transporters and mutations may be involved in MDR in Z. tritici.

  20. Effect of prothioconazole-based fungicides on Fusarium head blight, grain yield and deoxynivalenol accumulation in wheat under field conditions

    Directory of Open Access Journals (Sweden)

    Miriam HAIDUKOWSKI

    2012-05-01

    Full Text Available The effect of triazole-based treatments on Fusarium head blight (FHB, grain yields and the accumulation of deoxynivalenol (DON in harvested wheat kernels was evaluated by means of twenty multi-site field experiments performed during five consecutive growing seasons (from 2004‒2005 to 2008‒2009 in Italy. Fungicide treatments were carried out on different cultivars of common wheat (cv. Serio, Blasco, Genio and Savio and durum wheat (cv. Orobel, Saragolla, San Carlo, Levante, Duilio, Karur and Derrik after artificial inoculation with a mixture of toxigenic Fusarium graminearum and F. culmorum strains. The application of fungicides containing prothioconazole (Proline® or Prosaro® at the beginning of anthesis (BBCH 61 resulted in a consistent reduction of FHB disease severity (by between 39 and 93% and DON levels in wheat kernels (by between 40 and 91% and increased wheat yields (from 0.4 to 5.6 t ha-1, average 2.2 t ha-1, as compared to the untreated/inoculated control. Fungicides containing tebuconazole (Folicur® SE and cyproconazole plus prochloraz (Tiptor® Xcell showed a reduced effectiveness compared with prothioconazole-based treatments. All fungicide treatments were more effective in reducing DON and increasing grain yields of common wheat than durum wheat. Results showed that the application of fungicides containing prothioconazole at the beginning of anthesis provided a strong reduction of FHB disease, allowing both an increase in grain yields and a considerable reduction of DON content in wheat kernels.

  1. Effect of simulated rain on the efficiency of fungicides in potato late blight and early blight control

    Directory of Open Access Journals (Sweden)

    Jesus Guerino Tofoli

    2014-12-01

    Full Text Available Rainfastness of fungicides used in the control of late blight (Phytophthora infestans and early blight (Alternaria solani of potato was evaluated under green house and laboratory conditions. ‘Agata’ and ‘Monalisa’ plants treated with fungicides against both diseases were subjected to 20 mm controlled rain simulation for 6 min at 30 min, 1, 2, and 4 h after application. Once all leaves had dried, foliar discs were transferred to Petri dishes and inoculated with the respective pathogens. The plates were then incubated in a BOD chamber for a 12-h photoperiod at 18°C and 25°C, respectively. Disease severity was evaluated by determining the area (% of the foliar discs affected by disease on 5 and 7 days post-inoculation. The results suggest that systemic or inherent tenacity fungicides were less influenced by the simulated rain as compared to contact fungicides. An increase in drying time promoted higher control levels of both diseases, indicating a better retention and absorption of the tested fungicides.

  2. 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.

  3. Role of fungicides, application of nozzle types, and the resistance level of wheat varieties in the control of Fusarium head blight and deoxynivalenol.

    Science.gov (United States)

    Mesterházy, Akos; Tóth, Beáta; Varga, Monika; Bartók, Tibor; Szabó-Hevér, Agnes; Farády, László; Lehoczki-Krsjak, Szabolcs

    2011-11-01

    Fungicide application is a key factor in the control of mycotoxin contamination in the harvested wheat grain. However, the practical results are often disappointing. In 2000-2004, 2006-2008 and 2007 and 2008, three experiments were made to test the efficacy of fungicide control on Fusarium Head Blight (FHB) in wheat and to find ways to improve control of the disease and toxin contamination. In a testing system we have used for 20 years, tebuconazole and tebuconazole + prothioconazole fungicides regularly reduced symptoms by about 80% with a correlating reduction in toxin contamination. Averages across the years normally show a correlation of r = 0.90 or higher. The stability differences (measured by the stability index) between the poorest and the best fungicides are about 10 or more times, differing slightly in mycotoxin accumulation, FHB index (severity) and Fusarium damaged kernels (FDK). The weak fungicides, like carbendazim, were effective only when no epidemic occurred or epidemic severity was at a very low level. Similar fungicide effects were seen on wheat cultivars which varied in FHB resistance. In this study, we found three fold differences in susceptibility to FHB between highly susceptible and moderately resistant cultivars when treated with fungicides. In the moderately resistant cultivars, about 50% of the fungicide treatments lowered the DON level below the regulatory limit. In the most susceptible cultivars, all fungicides failed to reduce mycotoxin levels low enough for grain acceptance, in spite of the fact that disease was significantly reduced. The results correlated well with the results of the large-scale field tests of fungicide application at the time of natural infection. The Turbo FloodJet nozzle reduced FHB incidence and DON contamination when compared to the TeeJet XR nozzle. Overall, the data suggest that significant decreases in FHB incidence and deoxynivalenol contamination in field situations are possible with proper fungicide

  4. Role of Fungicides, Application of Nozzle Types, and the Resistance Level of Wheat Varieties in the Control of Fusarium Head Blight and Deoxynivalenol

    Directory of Open Access Journals (Sweden)

    Szabolcs Lehoczki-Krsjak

    2011-11-01

    Full Text Available Fungicide application is a key factor in the control of mycotoxin contamination in the harvested wheat grain. However, the practical results are often disappointing. In 2000–2004, 2006–2008 and 2007 and 2008, three experiments were made to test the efficacy of fungicide control on Fusarium Head Blight (FHB in wheat and to find ways to improve control of the disease and toxin contamination. In a testing system we have used for 20 years, tebuconazole and tebuconazole + prothioconazole fungicides regularly reduced symptoms by about 80% with a correlating reduction in toxin contamination. Averages across the years normally show a correlation of r = 0.90 or higher. The stability differences (measured by the stability index between the poorest and the best fungicides are about 10 or more times, differing slightly in mycotoxin accumulation, FHB index (severity and Fusarium damaged kernels (FDK. The weak fungicides, like carbendazim, were effective only when no epidemic occurred or epidemic severity was at a very low level. Similar fungicide effects were seen on wheat cultivars which varied in FHB resistance. In this study, we found three fold differences in susceptibility to FHB between highly susceptible and moderately resistant cultivars when treated with fungicides. In the moderately resistant cultivars, about 50% of the fungicide treatments lowered the DON level below the regulatory limit. In the most susceptible cultivars, all fungicides failed to reduce mycotoxin levels low enough for grain acceptance, in spite of the fact that disease was significantly reduced. The results correlated well with the results of the large-scale field tests of fungicide application at the time of natural infection. The Turbo FloodJet nozzle reduced FHB incidence and DON contamination when compared to the TeeJet XR nozzle. Overall, the data suggest that significant decreases in FHB incidence and deoxynivalenol contamination in field situations are possible with

  5. O-Methyl cyclolaudenol

    Directory of Open Access Journals (Sweden)

    Nisar Hussain

    2009-06-01

    Full Text Available The title compound (systematic name: 3-methoxy-24-methyl-9,19-cyclolanost-25-ene, C32H54O, is a triterpenoid which has been isolated from Skimmia laureola. The three six-membered rings adopt chair, slightly distorted half-chair and distorted boat conformations, and the five-membered ring adopts an envelope conformation. All the rings are trans fused.

  6. 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

  7. Structures of trihydroxynaphthalene reductase-fungicide complexes: implications for structure-based design and catalysis

    Energy Technology Data Exchange (ETDEWEB)

    Liao, D.-I.; Basarab, G.S.; Gatenby, A.A.; Valent, B.; Jordan, D.B. (DuPont)

    2010-03-08

    Trihydroxynaphthalene reductase catalyzes two intermediate steps in the fungal melanin biosynthetic pathway. The enzyme, a typical short-chain dehydrogenase, is the biochemical target of three commercial fungicides. The fungicides bind preferentially to the NADPH form of the enzyme. Three X-ray structures of the Magnaporthe grisea enzyme complexed with NADPH and two commercial and one experimental fungicide were determined at 1.7 {angstrom} (pyroquilon), 2.0 {angstrom} (2,3-dihydro-4-nitro-1H-inden-1-one, 1), and 2.1 {angstrom} (phthalide) resolutions. The chemically distinct inhibitors occupy similar space within the enzyme's active site. The three inhibitors share hydrogen bonds with the side chain hydroxyls of Ser-164 and Tyr-178 via a carbonyl oxygen (pyroquilon and 1) or via a carbonyl oxygen and a ring oxygen (phthalide). Active site residues occupy similar positions among the three structures. A buried water molecule that is hydrogen bonded to the NZ nitrogen of Lys-182 in each of the three structures likely serves to stabilize the cationic form of the residue for participation in catalysis. The pro S hydrogen of NADPH (which is transferred as a hydride to the enzyme's naphthol substrates) is directed toward the carbonyl carbon of the inhibitors that mimic an intermediate along the reaction coordinate. Modeling tetrahydroxynaphthalene and trihydroxynaphthalene in the active site shows steric and electrostatic repulsion between the extra hydroxyl oxygen of the former substrate and the sulfur atom of Met-283 (the C-terminal residue), which accounts, in part, for the 4-fold greater substrate specificity for trihydroxynaphthalene over tetrahydroxynaphthalene.

  8. Combined effects of drought and the fungicide tebuconazole on aquatic leaf litter decomposition.

    Science.gov (United States)

    Pesce, Stéphane; Zoghlami, Olfa; Margoum, Christelle; Artigas, Joan; Chaumot, Arnaud; Foulquier, Arnaud

    2016-04-01

    Loss of biodiversity and altered ecosystem functioning are driven by the cumulative effects of multiple natural and anthropogenic stressors affecting both quantity and quality of water resources. Here we performed a 40-day laboratory microcosm experiment to assess the individual and combined effects of drought and the model fungicide tebuconazole (TBZ) on leaf litter decomposition (LLD), a fundamental biogeochemical process in freshwater ecosystems. Starting out from a worst-case scenario perspective, leaf-associated microbial communities were exposed to severe drought conditions (four 5-day drought periods alternated with 4-day immersion periods) and/or a chronic exposure to TBZ (nominal concentration of 20μgL(-1)). We assessed the direct effects of drought and fungicide on the structure (biomass, diversity) and activity (extracellular enzymatic potential) of fungal and bacterial assemblages colonizing leaves. We also investigated indirect effects on the feeding rates of the amphipod Gammarus fossarum on leaves previously exposed to drought and/or TBZ contamination. Results indicate a stronger effect of drought stress than fungicide contamination under the experimental conditions applied. Indeed, the drought stress strongly impacted microbial community structure and activities, inhibiting the LLD process and leading to cascading effects on macroinvertebrate feeding. However, despite the lack of significant effect of TBZ applied alone, the effects of drought on microbial functions (i.e., decrease in LLD and in enzymatic activities) and on Gammarus feeding rates were more pronounced when drought and TBZ stresses were applied together. In a perspective of ecological risk assessment and ecosystem management for sustainability, these findings stress the need for deeper insight into how multiple stressors can affect the functioning of aquatic ecosystems and associated services.

  9. Non-target impact of fungicide tetraconazole on microbial communities in soils with different agricultural management.

    Science.gov (United States)

    Sułowicz, Sławomir; Cycoń, Mariusz; Piotrowska-Seget, Zofia

    2016-08-01

    Effect of the fungicide tetraconazole on microbial community in silt loam soils from orchard with long history of triazole application and from grassland with no known history of fungicide usage was investigated. Triazole tetraconazole that had never been used on these soils before was applied at the field rate and at tenfold the FR. Response of microbial communities to tetraconazole was investigated during 28-day laboratory experiment by determination of changes in their biomass and structure (phospholipid fatty acids method-PLFA), activity (fluorescein diacetate hydrolysis-FDA) as well as changes in genetic (DGGE) and functional (Biolog) diversity. Obtained results indicated that the response of soil microorganisms to tetraconazole depended on the management of the soils. DGGE patterns revealed that both dosages of fungicide affected the structure of bacterial community and the impact on genetic diversity and richness was more prominent in orchard soil. Values of stress indices-the saturated/monounsaturated PLFAs ratio and the cyclo/monounsaturated precursors ratio, were almost twice as high and the Gram-negative/Gram-positive ratio was significantly lower in the orchard soil compared with the grassland soil. Results of principal component analysis of PLFA and Biolog profiles revealed significant impact of tetraconazole in orchard soil on day 28, whereas changes in these profiles obtained for grassland soil were insignificant or transient. Obtained results indicated that orchards soil seems to be more vulnerable to tetraconazole application compared to grassland soil. History of pesticide application and agricultural management should be taken into account in assessing of environmental impact of studied pesticides.

  10. Copper oxychloride fungicide and its effect on growth and oxidative stress of potato plants.

    Science.gov (United States)

    Ferreira, Leonardo Cesar; Scavroni, Joseane; da Silva, João Renato Vaz; Cataneo, Ana Catarina; Martins, Dagoberto; Boaro, Carmen Sílvia Fernandes

    2014-06-01

    Excess copper in plants causes physiological alterations that lead to crop productivity losses. However, cupric fungicides have been utilized in the control of Alternaria solani and Phytophthora infestans fungi, which cause early blight and late blight in potato, respectively. Thus, this study aimed to investigate the effect of different copper oxychloride levels on potato plants through some biochemical and physiological parameters. The fungicide was applied at the recommended level (2.50gL(-1)), at a reduced level (1.25gL(-1)), and at 5.00gL(-1), to simulate spraying in the field twice during the same period with the recommended level. The results revealed that superoxide dismutase (SOD, EC 1.15.1.1) protected plants against oxidative stress at the beginning of the cycle since lipoperoxide levels were low in that period. In addition, increased SOD activity positively correlated with increased usable leaf area for photosynthesis (leaf area ratio, LAR), photosynthetic effectiveness (net assimilation rate, NAR), and growth relative to pre-existing dry matter (relative growth rate, RGR). Concomitantly, there was a negative correlation between lipoperoxide levels and LAR and RGR. Plants randomly sprayed twice in the same period with the level recommended for potato crop protection in the field do not present damage regarding their development. However, additional studies are needed in order to reduce the use of copper fungicides in the control of early and late blight in potato crop production, then decreasing the release of copper in the environment. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. 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.

  12. 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

    2017-02-13

    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.

  13. Effects of fungicides and biofungicides on population density and community structure of soil oribatid mites.

    Science.gov (United States)

    Al-Assiuty, Abdel-Naieem I M; Khalil, Mohamed A; Ismail, Abdel-Wahab A; van Straalen, Nico M; Ageba, Mohamed F

    2014-01-01

    To compare the side-effects of chemical versus biofungicides on non-target organisms in agricultural soil, a study of population structure, spatial distribution and fecundity of oribatid mites, a diverse and species-rich group of microarthropods indicative of decomposer activity in soil was done. Plots laid out in agricultural fields of a research station in Egypt, were cultivated with cucumber and treated with two chemical fungicides: Ridomil Plus 50% wp (active ingredients=metalaxyl and copper oxychloride) and Dithane M-45 (active ingredient=mancozeb), and two biofungicides: Plant Guard (containing the antagonistic fungus Trichoderma harzianum) and Polyversum (containing the fungi-parasitic oomycete Pythium oligandrum). All treatments were done using both low-volume and high-volume spraying techniques to check whether any effects were dependent on the method of application. Oribatid mite communities were assessed from soil core samples collected during the growing season. Total abundance of oribatids was not different across the plots, but some species decreased in number, while one species increased. Species diversity and community equitability decreased with the application of chemical and biofungicides especially when using high-volume spraying. In control plots most oribatid species showed a significant degree of aggregation, which tended to decrease under fungicide treatment. Ridomil Plus, Plant Guard and Polyversum had a negative effect on the gravid/ungravid ratio of some species. Egg number averaged over the whole adult population was not directly related to the application of chemical and biofungicides but it showed a species-specific relationship with population density. In general biofungicides had a smaller effect on population size and community structure of oribatid mite species than chemical fungicides. The results indicate that biofungicides may be the preferred option when aiming to prevent side-effects on sensitive groups among the species

  14. Rational coformer or solvent selection for pharmaceutical cocrystallization or desolvation.

    Science.gov (United States)

    Abramov, Yuriy A; Loschen, Christoph; Klamt, Andreas

    2012-10-01

    It is demonstrated that the fluid-phase thermodynamics theory conductor-like screening model for real solvents (COSMO-RS) as implemented in the COSMOtherm software can be used for accurate and efficient screening of coformers for active pharmaceutical ingredient (API) cocrystallization. The excess enthalpy, H(ex) , between an API-coformer mixture relative to the pure components reflects the tendency of those two compounds to cocrystallize. Thus, predictive calculations may be performed with decent effort on a large set of molecular data in order to identify potentially new cocrystal systems. In addition, it is demonstrated that COSMO-RS theory allows reasonable ranking of coformers for API solubility improvement. As a result, experiments may be focused on those coformers, which have an increased probability of cocrystallization, leading to the largest improvement of the API solubility. In a similar way as potential coformers are identified for cocrystallization, solvents that do not tend to form solvates may be determined based on the highest H(ex) s with the API. The approach was successfully tested on tyrosine kinase inhibitor axitinib, which has a propensity to form relatively stable solvated structures with the majority of common solvents, as well as on thiophanate-methyl and thiophanate-ethyl benzimidazole fungicides, which form channel solvates.

  15. Impact of fungicide and insecticide use on non-target aquatic organisms in rice paddy fields

    Directory of Open Access Journals (Sweden)

    Alana Cristina Dorneles Wandscheer

    Full Text Available ABSTRACT: The intensive use of plant protection products in rice paddy fields ( Oryza sativa L. has caused concern about the environmental impact on communities of non-target organisms that are natural inhabitants in these agroecosystems. The purpose of this review is to analyze the data currently available in the literature about some important fungicides and insecticides (such as trifloxystrobin, tebuconazole, tricyclazole, lambda-cyhalothrin, and thiamethoxam, which are currently used to control pests and diseases in rice paddy fields, as well as their effects on the community of non-target aquatic organisms.

  16. Triazole fungicides can induce cross-resistance to medical triazoles in Aspergillus fumigatus.

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    Eveline Snelders

    Full Text Available BACKGROUND: Azoles play an important role in the management of Aspergillus diseases. Azole resistance is an emerging global problem in Aspergillus fumigatus, and may develop through patient therapy. In addition, an environmental route of resistance development has been suggested through exposure to 14α-demethylase inhibitors (DMIs. The main resistance mechanism associated with this putative fungicide-driven route is a combination of alterations in the Cyp51A-gene (TR(34/L98H. We investigated if TR(34/L98H could have developed through exposure to DMIs. METHODS AND FINDINGS: Thirty-one compounds that have been authorized for use as fungicides, herbicides, herbicide safeners and plant growth regulators in The Netherlands between 1970 and 2005, were investigated for cross-resistance to medical triazoles. Furthermore, CYP51-protein homology modeling and molecule alignment studies were performed to identify similarity in molecule structure and docking modes. Five triazole DMIs, propiconazole, bromuconazole, tebuconazole, epoxiconazole and difenoconazole, showed very similar molecule structures to the medical triazoles and adopted similar poses while docking the protein. These DMIs also showed the greatest cross-resistance and, importantly, were authorized for use between 1990 and 1996, directly preceding the recovery of the first clinical TR(34/L98H isolate in 1998. Through microsatellite genotyping of TR(34/L98H isolates we were able to calculate that the first isolate would have arisen in 1997, confirming the results of the abovementioned experiments. Finally, we performed induction experiments to investigate if TR(34/L98H could be induced under laboratory conditions. One isolate evolved from two copies of the tandem repeat to three, indicating that fungicide pressure can indeed result in these genomic changes. CONCLUSIONS: Our findings support a fungicide-driven route of TR(34/L98H development in A. fumigatus. Similar molecule structure

  17. Survey and Screening of Fungicide for the Control of Tomato Black Leaf Mold Pseudocercospora fuligena

    Directory of Open Access Journals (Sweden)

    Mun Haeng Lee

    2015-06-01

    Full Text Available Tomato black leaf molds were collected from the six metropolitan cities, which were occurred mainly from the end of August until November. There was no significant difference on the fungal growth between potato dextrose agar and tomato-oatmeal agar media. The mycelial growth of the fungus was robust at a relatively high temperature, from 28 to 30°C. The suppression rates of hyphal growth ranged from 17-98% on the media supplemented with four different chemicals such as difenoconazole, fluquinconazole and prochloraz manganese complex, metconazole, and flutianil and there is no different suppression rates of the fungicides on the tested Pseudocercospora fuligena isolates.

  18. Methylation in hepatocellular carcinoma

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    Regina M. Santella

    2007-02-01

    Full Text Available

    The development of HCC is a complex, multistep, multistage process. The molecular pathogenesis of HCC appears to involve multiple genetic aberrations in the molecular control of hepatocyte proliferation, differentiation and death and the maintenance of genomic integrity. This process is influenced by the cumulative activation and inactivation of oncogenes, tumor suppressor genes and other genes. p53, a tumor suppressor gene, is the most frequently mutated gene in human cancers. There is also a striking sequence specific binding and induction of mutations by AFB1 at codon 249 of p53 in HCC.

    Epigenetic alterations are also involved in cancer development and progression. Methylation of promoter CpG islands is associated with inhibition of transcriptional initiation and permanent silencing of downstream genes.

    It is now known that most important tumor suppressor genes are inactivated, not only by mutations and deletions but also by promoter methylation. Several studies indicated that p16, p15, RASSF1A, MGMT, and GSTP1 promoter hypermethylation are prevalent in HCC. In addition, geographic variation in the methylation status of tumor DNA indicates that environmental factors may influence the frequent and concordant degree of hypermethylation in multiple genes in HCC and that epigeneticenvironmental interactions may be involved in hepatocarcinogenesis. We have found significant relationships between promoter methylation and AFB1-DNA adducts confirming the impact of environmental exposures on gene methylation.

    DNA isolated from serum or plasma of cancer patients frequently contains the same genetic and

  19. 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...... petals adhering to the fruit or trapped under the calyx. To implement biological control agents (BCAs) as an alternative control measure, it is crucial that the BCAs are able to colonize flower parts rapidly to combat B. cinerea. The combination of fungicides with BCAs may enhance and stabilise...... the efficacy of BCAs. The underlying mechanism for such positive combination effects may be related to an improved establishment of the BCAs when their natural competitors have been adversely affected by the fungicide or that the B. cinerea infection has been slowed down. The present work report results on 1...

  20. Chlorophyll fluorescence of epiphytic lichens under acid, ammonium and fungicide stress - a comparison of laboratory and field results

    Energy Technology Data Exchange (ETDEWEB)

    Luebke, K.; Tremp, H. [Hohenheim Univ., Stuttgart (Germany). Inst. for Landscape and Plant Ecology

    2002-07-01

    Fungicide treatment (dithiocarbamate) caused a significant reduction of the quantum yield of photochemical energy conversion of the tested lichen species Parmelia sulcata and Parmelia subrudecta under laboratory conditions. Especially P. subrudecta showed a rapid decrease of photosynthetic capacity in between one week and was more susceptible to fungicide stress compared to Parmelia sulcata. Over the time span of four weeks, sulphuric acid and ammonium sulphate induced no significant changes of fluorescence parameters. At natural stands (lichens on apple tree bark) the same fungicide was applied. Here no vitality-decline (visual verification, yield parameter) was detectable. So results from laboratory are not transferable on lichen living under natural habitat conditions, because removing lichens from tree bark causes additional stress to species. Results obtained from ecotoxicological laboratory experiments should be carefully proven and if possible completed and verified under more realistic background situations. (orig.)

  1. Evaluation of the Efficacy of Different Fungicide for the Management of Alternaria Leaf Spot Disease of Chilli

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Yadav

    2015-03-01

    Full Text Available Alternaria leaf spot of chilli caused by Alternaria alternate is an important disease affecting chilly production areas in India. The disease is primarily controlled through the use of fungicidal seed treatments. In this study, different fungicides viz. Captol, Captan, Ziram, Captofol, Thiram, Indofill Z 78 and Indofill Z 45 were assessed for their ability to reduce the growth of Alternaria alternata under laboratory conditions. Maximum inhibition (100% was achieved by Captol and capton followed by captofol (89.5 % while 0.1 % dose given. This paper reports the efficacy of fungicides that can be used under field conditions to control alternaria leaf spot in tropical regions and demonstrates the use of a method of application that could significantly improve the efficacy of disease control.

  2. Screening fungicides for use in fish culture: Evaluation of the agar plug transfer, cellophane transfer, and agar dilution methods

    Science.gov (United States)

    Bailey, Tom A.

    1983-01-01

    The reliability, reproducibility, and usefulness of three screening methods -- the cellophane transfer, the agar plug transfer, and the agar dilution -- to screen aquatic fungicides were evaluated. Achlya flagellata and Saprolegnia hypogyna were exposed to 1, 10, and 100 mg/L of malachite green to test each method. The cellophane transfer and agar plug transfer techniques had similar reliability and reproducibility in rating fungicidal activity, and were both superior to the agar dilution technique. The agar plug transfer and agar dilution techniques adequately projected in vivo activity of malachite green, but the cellophane transfer technique overestimated its activity. Overall, the agar plug transfer technique most accurately rated the activity of malachite green and was the easiest test to perform. It therefore appears to be the method of choice for testing aquatic fungicides.

  3. Identification of the Fungal Pathogen that Causes Strawberry Anthracnose in Bangladesh and Evaluation of In Vitro Fungicide Activity

    Science.gov (United States)

    Akhter, Md. Shamim; Alam, Shahidul; Islam, Md. Shafiqul

    2009-01-01

    This study was conducted to identify the Colletotrichum species causing anthracnose disease of strawberry in Balgladesh and to evaluate in vitro activity of commercial fungicides it. Based on morphological and cultural characteristics, all 22 isolates were identified as Colletotrichum gloeosporioides. They developed white or glittery colonies with grey to dark grey reverse colony colors and they produced cylindrical conidia. The efficacy of five commercial fungicides, Bavistin DF, Dithane M-45, Sulcox 50 WP, Corzim 50 WP and Rovral 50 WP, were tested against the fungus. Bavistin inhibited radial growth completely and was followed in efficacy by Dithane M-45. In Bavistin DF treated media, the fungus did not produce conidia. The percent inhibition of radial growth of the fungus was increased with the increasing concentrations of fungicide. PMID:23983513

  4. Determination of Six Pyrazole Fungicides in Grape Wine by Solid-Phase Extraction and Gas Chromatography-Tandem Mass Spectrometry.

    Science.gov (United States)

    Shen, Yan; Li, Zhou; Ma, Qiang; Wang, Chuanxian; Chen, Xiangzhun; Miao, Qian; Han, Chao

    2016-05-18

    A gas chromatography-tandem mass spectrometry (GC-MS/MS) method was developed for the first simultaneous identification and quantification of six pyrazole fungicides (furametpyr, rabenzazole, fluxapyroxad, penflufen, bixafen, and isopyrazam) in grape wine samples. The grape wine samples were first diluted with water, then purified by solid-phase extraction, and finally examined by GC-MS/MS in multiple reaction monitoring (MRM) mode. Matrix-matched calibration curves were used to correct the matrix effects. The limits of quantification (LOQs), calculated as 10 times the standard deviation, were 0.2-0.8 μg kg(-1) for the six pyrazole fungicides. The average recoveries were in the range of 74.3-94.5%, with relative standard deviations (RSDs) below 5.8%, measured at three concentration levels. The proposed method is suitable for the simultaneous determination of six pyrazole fungicides in grape wine samples.

  5. Identification of Multiple Cryptococcal Fungicidal Drug Targets by Combined Gene Dosing and Drug Affinity Responsive Target Stability Screening

    Directory of Open Access Journals (Sweden)

    Yoon-Dong Park

    2016-08-01

    Full Text Available Cryptococcus neoformans is a pathogenic fungus that is responsible for up to half a million cases of meningitis globally, especially in immunocompromised individuals. Common fungistatic drugs, such as fluconazole, are less toxic for patients but have low efficacy for initial therapy of the disease. Effective therapy against the disease is provided by the fungicidal drug amphotericin B; however, due to its high toxicity and the difficulty in administering its intravenous formulation, it is imperative to find new therapies targeting the fungus. The antiparasitic drug bithionol has been recently identified as having potent fungicidal activity. In this study, we used a combined gene dosing and drug affinity responsive target stability (GD-DARTS screen as well as protein modeling to identify a common drug binding site of bithionol within multiple NAD-dependent dehydrogenase drug targets. This combination genetic and proteomic method thus provides a powerful method for identifying novel fungicidal drug targets for further development.

  6. Methylation profiling using methylated DNA immunoprecipitation and tiling array hybridization.

    Science.gov (United States)

    Cheung, Hoi-Hung; Lee, Tin-Lap; Rennert, Owen M; Chan, Wai-Yee

    2012-01-01

    DNA methylation is an important epigenetic modification that regulates development and plays a role in the pathophysiology of many diseases. It is dynamically changed during germline development. Methylated DNA immunoprecipitation (MeDIP) is an efficient, cost-effective method for locus-specific and genome-wide analysis. Methylated DNA fragments are enriched by a 5-methylcytidine-recognizing antibody, therefore allowing the analysis of both CpG and non-CpG methylation. The enriched DNA fragments can be amplified and hybridized to tiling arrays covering CpG islands, promoters, or the entire genome. Comparison of different methylomes permits the discovery of differentially methylated regions that might be important in disease- or tissue-specific expression. Here, we describe an established MeDIP protocol and tiling array hybridization method for profiling methylation of testicular germ cells.

  7. Event extraction for DNA methylation

    Directory of Open Access Journals (Sweden)

    Ohta Tomoko

    2011-10-01

    Full Text Available Abstract Background We consider the task of automatically extracting DNA methylation events from the biomedical domain literature. DNA methylation is a key mechanism of epigenetic control of gene expression and implicated in many cancers, but there has been little study of automatic information extraction for DNA methylation. Results We present an annotation scheme for DNA methylation following the representation of the BioNLP shared task on event extraction, select a set of 200 abstracts including a representative sample of all PubMed citations relevant to DNA methylation, and introduce manual annotation for this corpus marking nearly 3000 gene/protein mentions and 1500 DNA methylation and demethylation events. We retrain a state-of-the-art event extraction system on the corpus and find that automatic extraction of DNA methylation events, the methylated genes, and their methylation sites can be performed at 78% precision and 76% recall. Conclusions Our results demonstrate that reliable extraction methods for DNA methylation events can be created through corpus annotation and straightforward retraining of a general event extraction system. The introduced resources are freely available for use in research from the GENIA project homepage http://www-tsujii.is.s.u-tokyo.ac.jp/GENIA.

  8. Long-term effects of fungicides on leaf-associated microorganisms and shredder populations-an artificial stream study.

    Science.gov (United States)

    Zubrod, Jochen P; Englert, Dominic; Wolfram, Jakob; Rosenfeldt, Ricki R; Feckler, Alexander; Bundschuh, Rebecca; Seitz, Frank; Konschak, Marco; Baudy, Patrick; Lüderwald, Simon; Fink, Patrick; Lorke, Andreas; Schulz, Ralf; Bundschuh, Mirco

    2017-02-04

    Leaf litter is a major source of carbon and energy for stream food webs, while both leaf-decomposing microorganisms and macroinvertebrate leaf shredders can be affected by fungicides. Despite the potential for season-long fungicide exposure for these organisms, however, such chronic exposures have not yet been considered. Using an artificial stream facility, effects of a chronic (lasting up to 8 wk) exposure to a mixture of 5 fungicides (sum concentration 20 μg/L) on leaf-associated microorganisms and the key leaf shredder Gammarus fossarum were therefore assessed. While bacterial density and microorganism-mediated leaf decomposition remained unaltered, fungicide exposure reduced fungal biomass (≤71%) on leaves from day 28 onward. Gammarids responded to the combined stress from consumption of fungicide-affected leaves and waterborne exposure with a reduced abundance (≤18%), which triggered reductions in final population biomass (18%) and in the number of precopula pairs (≤22%) but could not fully explain the decreased leaf consumption (19%), lipid content (≤43%; going along with an altered composition of fatty acids), and juvenile production (35%). In contrast, fine particulate organic matter production and stream respiration were unaffected. Our results imply that long-term exposure of leaf-associated fungi and shredders toward fungicides may result in detrimental implications in stream food webs and impairments of detrital material fluxes. These findings render it important to understand decomposer communities' long-term adaptational capabilities to ensure that functional integrity is safeguarded. Environ Toxicol Chem 2017;9999:1-12. © 2017 SETAC.

  9. A review of current knowledge of resistance aspects for the next-generation succinate dehydrogenase inhibitor fungicides.

    Science.gov (United States)

    Sierotzki, Helge; Scalliet, Gabriel

    2013-09-01

    The new broad-spectrum fungicides from the succinate dehydrogenase inhibitor (SDHI) class have been quickly adopted by the market, which may lead to a high selection pressure on various pathogens. Cases of resistance have been observed in 14 fungal pathogens to date and are caused by different mutations in genes encoding the molecular target of SDHIs, which is the mitochondrial succinate dehydrogenase (SDH) enzyme. All of the 17 marketed SDHI fungicides bind to the same ubiquinone binding site of the SDH enzyme. Their primary biochemical mode of action is the blockage of the TCA cycle at the level of succinate to fumarate oxidation, leading to an inhibition of respiration. Homology models and docking simulations explain binding behaviors and some peculiarities of the cross-resistance profiles displayed by different members of this class of fungicides. Furthermore, cross-resistance patterns among SDHIs is complex because many mutations confer full cross resistance while others do not. The nature of the mutations found in pathogen populations varies with species and the selection compound used but cross resistance between all SDHIs has to be assumed at the population level. In most of the cases where resistance has been reported, the frequency is still too low to impact field performance. However, the Fungicide Resistance Action Committee has developed resistance management recommendations for pathogens of different crops in order to reduce the risk for resistance development to this class of fungicides. These recommendations include preventative usage, mixture with partner fungicides active against the current pathogen population, alternation in the mode of action of products used in a spray program, and limitations in the total number of applications per season or per crop.

  10. Fungicide-driven evolution and molecular basis of multidrug resistance in field populations of the grey mould fungus Botrytis cinerea.

    Directory of Open Access Journals (Sweden)

    Matthias Kretschmer

    2009-12-01

    Full Text Available The grey mould fungus Botrytis cinerea causes losses of commercially important fruits, vegetables and ornamentals worldwide. Fungicide treatments are effective for disease control, but bear the risk of resistance development. The major resistance mechanism in fungi is target protein modification resulting in reduced drug binding. Multiple drug resistance (MDR caused by increased efflux activity is common in human pathogenic microbes, but rarely described for plant pathogens. Annual monitoring for fungicide resistance in field isolates from fungicide-treated vineyards in France and Germany revealed a rapidly increasing appearance of B. cinerea field populations with three distinct MDR phenotypes. All MDR strains showed increased fungicide efflux activity and overexpression of efflux transporter genes. Similar to clinical MDR isolates of Candida yeasts that are due to transcription factor mutations, all MDR1 strains were shown to harbor activating mutations in a transcription factor (Mrr1 that controls the gene encoding ABC transporter AtrB. MDR2 strains had undergone a unique rearrangement in the promoter region of the major facilitator superfamily transporter gene mfsM2, induced by insertion of a retrotransposon-derived sequence. MDR2 strains carrying the same rearranged mfsM2 allele have probably migrated from French to German wine-growing regions. The roles of atrB, mrr1 and mfsM2 were proven by the phenotypes of knock-out and overexpression mutants. As confirmed by sexual crosses, combinations of mrr1 and mfsM2 mutations lead to MDR3 strains with higher broad-spectrum resistance. An MDR3 strain was shown in field experiments to be selected against sensitive strains by fungicide treatments. Our data document for the first time the rising prevalence, spread and molecular basis of MDR populations in a major plant pathogen in agricultural environments. These populations will increase the risk of grey mould rot and hamper the effectiveness of

  11. Fungicide-driven evolution and molecular basis of multidrug resistance in field populations of the grey mould fungus Botrytis cinerea.

    Directory of Open Access Journals (Sweden)

    Matthias Kretschmer

    2009-12-01

    Full Text Available The grey mould fungus Botrytis cinerea causes losses of commercially important fruits, vegetables and ornamentals worldwide. Fungicide treatments are effective for disease control, but bear the risk of resistance development. The major resistance mechanism in fungi is target protein modification resulting in reduced drug binding. Multiple drug resistance (MDR caused by increased efflux activity is common in human pathogenic microbes, but rarely described for plant pathogens. Annual monitoring for fungicide resistance in field isolates from fungicide-treated vineyards in France and Germany revealed a rapidly increasing appearance of B. cinerea field populations with three distinct MDR phenotypes. All MDR strains showed increased fungicide efflux activity and overexpression of efflux transporter genes. Similar to clinical MDR isolates of Candida yeasts that are due to transcription factor mutations, all MDR1 strains were shown to harbor activating mutations in a transcription factor (Mrr1 that controls the gene encoding ABC transporter AtrB. MDR2 strains had undergone a unique rearrangement in the promoter region of the major facilitator superfamily transporter gene mfsM2, induced by insertion of a retrotransposon-derived sequence. MDR2 strains carrying the same rearranged mfsM2 allele have probably migrated from French to German wine-growing regions. The roles of atrB, mrr1 and mfsM2 were proven by the phenotypes of knock-out and overexpression mutants. As confirmed by sexual crosses, combinations of mrr1 and mfsM2 mutations lead to MDR3 strains with higher broad-spectrum resistance. An MDR3 strain was shown in field experiments to be selected against sensitive strains by fungicide treatments. Our data document for the first time the rising prevalence, spread and molecular basis of MDR populations in a major plant pathogen in agricultural environments. These populations will increase the risk of grey mould rot and hamper the effectiveness of

  12. The effect of selected fungicides on the chemical composition of strawberry fruits and contamination with dithiocarbamate residues

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    Wysocki Karol

    2014-12-01

    Full Text Available In a four-year field experiment, fenhexamid, iprodione, pyrimethanil and thiram were applied in four different series as fungicides recommended for the control of grey mold (Botrytis cinerea in strawberries. The plant protection products had no significant effect on the chemical composition of strawberry fruits of the Kent and Senga Sengana cultivars with the exception of an increase in the vitamin C level in ‘Kent’ strawberries. They also contributed to minor variations in the content of extract, total sugars, organic acids, polyphenols and anthocyanins. Dithiocarbamate residues were detected in all samples from the first harvest of strawberries that had been treated with the thiram fungicide

  13. Integrated control of white rot disease on beans caused by Sclerotinia sclerotiorum using Contans® and reduced fungicides application.

    Science.gov (United States)

    Elsheshtawi, Mohamed; Elkhaky, Maged T; Sayed, Shaban R; Bahkali, Ali H; Mohammed, Arif A; Gambhir, Dikshit; Mansour, Aref S; Elgorban, Abdallah M

    2017-02-01

    This study was conducted to determine the compatibility of Contans® (Coniothyrium minitans) with fungicides against Sclerotinia sclerotiorum. Results showed that both Contans® and Topsin® significantly reduced the disease incidence caused by S. sclerotiorum by 90% and 95% survival plants, respectively when they were individually applied and compared to control. While, soil application of Contans® and Sumisclex mixture was the most effective in suppressing the white rot disease incidence that produced 100% survival plants, application of C. minitans combined with the reduced doses of fungicides would be advantageous in saving labor cost, thus increasing production efficiency of bean.

  14. Orchard factors associated with resistance and cross resistance to sterol demethylation inhibitor fungicides in populations of Venturia inaequalis from Pennsylvania.

    Science.gov (United States)

    Pfeufer, Emily E; Ngugi, Henry K

    2012-03-01

    Orchard management practices, such as destroying of overwintered inoculum and limiting the number of fungicide applications, are often recommended as tactics for slowing the development of resistance to sterol demethylation-inhibitor (DMI) fungicides in populations of Venturia inaequalis. However, there is little quantitative evidence relating the use of such practices to levels of resistance in orchards. The aim of this study was to evaluate the sensitivity of V. inaequalis isolates from Pennsylvania to DMI fungicides, and to identify orchard management factors related to the incidence of resistant isolates. In total, 644 single-spore V. inaequalis cultures obtained from 20 apple orchards in 2008 or 2009 were tested for sensitivity to myclobutanil, fenbuconazole, or difenoconazole. Growers provided management history of the sampled plots. Widespread shifts toward resistance to the three fungicides were noted, with mean effective concentration for 50% inhibition (EC(50)) values of 2.136, 0.786, and 0.187 μg/ml for myclobutanil, fenbuconazole, and difenoconazole, respectively. Cross resistance to the three fungicides was documented in high correlation (Spearman's r > 0.6) between mean EC(50) values for 14 orchards. Based on a 0.5-μg/ml threshold, 66 and 26% of isolates were resistant to myclobutanil and fenbuconazole, respectively, and 22% were cross resistant to the two fungicides. A significant between-year shift toward increased resistance was noted in two of three orchards surveyed in both years. Failure to use dormant copper sprays, older trees, larger orchards, orchards with ≤10 cultivars, and application of >4 DMI sprays were positively correlated (0.0001 resistant isolates. Isolates from orchards with >4 DMI sprays were four times as likely to be resistant to fenbuconazole (odds ratio = 4.57; P = 0.015). Isolates from orchards without dormant copper sprays were twice as likely to be cross-shifted toward resistance to all three fungicides (odds ratio = 1

  15. 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

    2016-01-01

    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. PMID:27629523

  16. 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.

  17. 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.

  18. Double edge Sword Behavior of Carbendazim: A Potent Fungicide With Anti-Cancer Therapeutic Properties.

    Science.gov (United States)

    Goyal, Karan; Sharma, Ajay; Arya, Ridhima; Sharma, Rohit; Gupta, Girish K; Sharma, Anil K

    2016-12-21

    A number of benzimidazole derivatives such as benomyl and carbendazim have been known for their potential role as agricultural fungicides. Simultaneously carbendazim has also been found to inhibit proliferation of mammalian tumor cells specifically drug and multidrug resistant cell lines. Studies carried out with fungal and mammalian cells have highlighted the potential role of carbendazim in inhibiting proliferation of cells, thereby exhibiting therapeutic implications against cancer. Because of its promising preclinical antitumor activity, Carbendazim had undergone phase I clinical trials and is under further clinical investigations for treatment of cancer. A number of theoretical interactions have been pinpointed. There are many anticancer drugs in the market, but their usefulness is limited because of drug resistance in a significant proportion of patients. The hunger for newer drugs drives anticancer drug discovery research on a global platform and requires innovations to ensure a sustainable pipeline of lead compounds. Current review highlights the dual role of carbendazim as a fungicide and an anticancer agent. We also discuss about the harmful effects of carbendazim and emphasize upon the need for more pharmacokinetic studies and pharmacovigilance data to ascertain its clinical significance.

  19. Variation in Sensitivity Among Some Isolates of Macrophomina phaseolina Isolated from Cotton Roots to Flutolanil Fungicide.

    Science.gov (United States)

    Mahmoud, Yehia A G; Aly, A A; Omar, M R; Ismail, Abdel-Wahab A

    2006-06-01

    Toxicity of the fungicide Flutolanil was in vitro tested against 20 isolates of Macrophomina phaseolina and cotton seedlings of ten commercial cotton cultivars. The isolates were recovered from roots of cotton plants obtained from different cotton-growing areas in Egypt. Most of the tested isolates were sensitive to Flutolanil; however, they varied in sensitivity. Twenty-five percent of the isolates were highly sensitive where IC50 ranged from 100 µg/ml. Flutolanil was very safe on both shoots and roots of the tested cultivars (IC50 > 100 µg/ml). Treating cotton seeds with Flutolanil resulted in highly significant (P < 0.01) reductions in pathogenicity of 18 isolates and a significant reduction (P < 0.05) in pathogenicity of isolate M29. M1 was the only isolate, which was insensitive to the application of Flutolanil. In vivo toxicity to Flutolanil was not correlated with its in vitro toxicity. However, a highly significant correlation (r = 0.60, P < 0.01) was observed between pathogenicity of isolates and the in vivo toxicity of the fungicide.

  20. Fungicides and Application Timing for Control of Early Leafspot, Southern Blight, and Sclerotinia Blight of Peanut

    Directory of Open Access Journals (Sweden)

    W. James Grichar

    2016-01-01

    Full Text Available Field studies were conducted in 2013 and 2014 in south Texas near Yoakum and from 2008 to 2011 in central Texas near Stephenville to evaluate various fungicides for foliar and soilborne disease control as well as peanut yield response under irrigation. Control of Sclerotinia blight caused by Sclerotinia minor Jagger with penthiopyrad at 1.78 L/ha was comparable to fluazinam or boscalid; however, the 1.2 L/ha dose of penthiopyrad did not provide consistent control. Peanut yield was reduced with the lower penthiopyrad dose when compared with boscalid, fluazinam, or the high dose of penthiopyrad. Control of early leaf spot, caused by Cercospora arachidicola S. Hori or southern blight, caused by Sclerotium rolfsii Sacc., with penthiopyrad in a systems approach was comparable with propiconazole, prothioconazole, or pyraclostrobin systems and resulted in disease control that was higher than the nontreated control. Peanut yield was also comparable with the penthiopyrad, propiconazole, prothioconazole, or pyraclostrobin systems and reflects the ability of the newer fungicides to control multiple diseases found in Texas peanut production.

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

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    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.

  2. Structure-based designing of sordarin derivative as potential fungicide with pan-fungal activity.

    Science.gov (United States)

    Chakraborty, Biprashekhar; Sejpal, Nikunjkumar Vinodray; Payghan, Pavan V; Ghoshal, Nanda; Sengupta, Jayati

    2016-05-01

    Fungal infections have become a significant problem for immunosuppressed patients. Sordarin, a promising fungicidal agent, inhibits fungal protein synthesis by impairing elongation factor-2 (eEF2) function. Intriguingly, despite high sequence similarity among eEF2s from different species, sordarin has been shown to inhibit translation specifically in certain fungi while unable to do so in some other fungal species (e.g. Candida parapsilosis and Candida lusitaniae). The sordarin binding site on eEF2 as well as its mechanism of action is known. In a previous study, we have detailed the interactions between sordarin and eEF2 cavities from different fungal species at the molecular level and predicted the probable cause of sordarin sensitivity. Guided by our previous analysis, we aimed for computer-aided designing of sordarin derivatives as potential fungicidal agents that still remain ineffective against human eEF2. We have performed structural knowledge-based designing of several sordarin derivatives and evaluated predicted interactions of those derivatives with the sordarin-binding cavities of different eEF2s, against which sordarin shows no inhibitory action. Our analyses identify an amino-pyrrole derivative as a good template for further designing of promising broad-spectrum antifungal agents. The drug likeness and ADMET prediction on this derivative also supports its suitability as a drug candidate.

  3. Chiral separation of metalaxyl and benalaxyl fungicides by electrokinetic chromatography and determination of enantiomeric impurities.

    Science.gov (United States)

    Pérez-Fernández, Virginia; García, Maria Ángeles; Marina, Maria Luisa

    2011-07-29

    The enantiomers of two acylamine fungicides (metalaxyl and benalaxyl) were separated by EKC using CDs as chiral selectors. The use of 15 mM succinyl-γ-CD for metalaxyl and 5 mM succinyl-β-CD for benalaxyl dissolved in a 50 mM 2-morpholinoethanesulfonic acid buffer (pH 6.5), enabled the chiral separation of metalaxyl enantiomers in 11.5 min with a resolution of 3.1 and the enantiomeric separation of benalaxyl in 7.5 min with a resolution close to 15. Under these conditions, the two enantiomers of each of the chiral compound studied were also separated from folpet, very commonly present in fungicide formulations containing metalaxyl or benalaxyl. The analytical characteristics of the two developed methods were studied in terms of precision, linearity, selectivity, limits of detection (LODs) and limits of quantitation (LOQs) showing their suitability for the determination of these compounds in commercial agrochemical formulations. Finally, the development of an in-capillary preconcentration strategy allowed the detection of enantiomeric impurities up to 1.2% in commercial products labeled as enantiomerically pure in metalaxyl-M. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Physiological changes promoted by a strobilurin fungicide in the rice-Bipolaris oryzae interaction.

    Science.gov (United States)

    Debona, D; Nascimento, K J T; Gomes, J G O; Aucique-Perez, C E; Rodrigues, F A

    2016-06-01

    Strobilurins are among the most important fungicides that are used for plant disease control worldwide. In addition to their fungicide effect, strobilurins can also improve crop physiology. Nonetheless, the impact of azoxystrobin (Az), the main marketed strobilurin, on rice physiology is still unknown. Detailed gas exchange measurements and chlorophyll a fluorescence analysis were used to examine the Az effects on the photosynthetic performance of rice plants (cultivar Metica-1) either challenged or not with Bipolaris oryzae, the causal agent of brown spot. Az impaired carbon (C) fixation in the non-inoculated plants in a manner that was not related to photochemical or biochemical limitations, but rather to decreased stomatal conductance that limited the CO2 influx into the mesophyll cells. The photosynthesis of rice plants that were not sprayed with Az dramatically decreased upon B. oryzae infection, which was chiefly governed by photochemical and biochemical limitations. The energy surplus that was caused by limited C fixation in the rice plants that were treated with Az and inoculated with B. oryzae was thermally and effectively dissipated until 72h after inoculation. In Az absence, however, this mechanism was not sufficient to prevent chronic photoinhibition to photosynthesis. The inoculated plants were not able to fully capture and exploit the collected light energy, but these constraints were greatly limited in the presence of Az. In conclusion, Az impaired the photosynthetic performance of non-infected plants by diffusive constraints, but prevented, to a greater extent, the damage to the photosynthetic apparatus during the infection process of B. oryzae.

  5. Assessment of acute toxicity and histopathology of the fungicide captan in rainbow trout.

    Science.gov (United States)

    Boran, Halis; Capkin, Erol; Altinok, Ilhan; Terzi, Ertugrul

    2012-03-01

    Acute toxicity of the fungicide, captan, to juvenile rainbow trout was evaluated under static-renewal test condition. Actual concentrations of captan ranged from 0.05 to 1.00 mg/L. The concentrations of captan that killed 50% of the rainbow trout (3.11±0.8 g) within 24 (24 h; LC(50)), 48, 72 and 96 h were 0.57±0.09, 0.49±0.10, 0.44±0.11 and 0.38±0.13 mg/L (95% confidence limits), respectively. None of the unexposed control fish died and the first fish died 6 h after exposure to captan (≥0.65 mg/L). Hypertrophy, separation of epithelium from lamellae, lamellar fusion, and epithelial cell necrosis were observed on captan exposed fish. Gills also had scattered areas of focal lamellar hyperplasia. Fish exposed to fungicide had inflammation and necrosis in liver, trunk kidney and spleen. In order, the most affected organs were gill, trunk kidney and liver.

  6. Control of Asian soybean rust with mancozeb, a multi-site fungicide

    Directory of Open Access Journals (Sweden)

    Luís Henrique Carregal Pereira da Silva

    2015-03-01

    Full Text Available An experiment conducted in the field the action of mancozeb, a fungicide of multi-site action was tested, to control soybean rust caused by Phakopsora pachyrhizi. Its performance was compared to that of the mixture cyproconazole (DMI + azoxystrobin (QoI. The soybean cultivar NA 7337 RR was used with a population of 400,000 plants/ha cultivated in 20m2 plots. Treatments consisted of mancozeb levels (1.5 and 2.0 kg/ha applied four, six and eight times. The DMI + QoI mixture was applied three times at 0.3 L/ha + Nimbus. Rust severity was assessed six times in the plots and data were integrated as the area under the disease progress curve (AUDPC. The plots were harvested and grain yield was expressed as kg/ha. Data on AUDPC and yield were subjected to analysis of variance and means compared according to Turkey's test (p = 0.005. Treatments with mancozeb were superior to DMI + QoI mixture both for rust control and grain yield. Four applications of 2.0 k/ha mancozeb were more efficient than three applications of the mixture used as standard. Mancozeb has the potential to be added to fungicide mixtures in the establishment of soybean rust anti-resistance strategy.

  7. In vitro resistance of Aspergillus fumigatus to azole farm fungicide.

    Science.gov (United States)

    Kano, Rui; Sobukawa, Hideto; Murayama, Somay Yamagata; Hirose, Dai; Tanaka, Yoko; Kosuge, Yasuhiro; Hasegawa, Atsuhiko; Kamata, Hiroshi

    2016-03-01

    Azole resistance in Aspergillus fumigatus is mainly due to a point mutation in the 14α-sterol demethylase (CYP51A) gene, which encodes the target of azole fungicides. Moreover, overexpression of CYP51B or multidrug resistance (MDR) gene is supposedly related to the mechanism of azole resistance in A. fumigatus. In this study, we tried to induce resistance to tetraconazole, an azole fungicide, in strains of A. fumigatus from a farm and then investigated mutation and expression of their CYP51A, CYP51B, and multidrug resistance (MDR) genes. Three tetraconazole resistant strains were induced and their minimum inhibitory concentration (MIC) for tetraconazole was 145 mg/L. However, the MICs of itraconazole (ITZ), posaconazole (POS), and voriconazole (VRZ) obtained by an E-test of the three tetraconazole resistant strains were 0.064-0.19 mg/L for ITZ, 0.023-0.32 mg/L for POS, and 0.047-0.064 mg/L for VRZ. No gene mutations were detected in the CYP 51A sequence amplified in these strains. RT-PCR of cyp51A and cyp51B indicated that the tetraconazole resistant strains more highly expressed these genes than the susceptible strain in tetraconazole containing medium.

  8. Biological characteristics and resistance analysis of the novel fungicide SYP-1620 against Botrytis cinerea.

    Science.gov (United States)

    Zhang, Xiaoke; Wu, Dongxia; Duan, Yabing; Ge, Changyan; Wang, Jianxin; Zhou, Mingguo; Chen, Changjun

    2014-09-01

    SYP-1620, a quinone-outside-inhibitor (QoI), is a novel broad-spectrum fungicide. In this study, 108 isolates of Botrytis cinerea from different geographical regions in Jiangsu Province of China were characterized for baseline sensitivity to SYP-1620. The curves of baseline sensitivity were unimodal with a mean EC50 value of 0.0130±0.0109 μg/mL for mycelial growth, 0.01147±0.0062 μg/mL for spore germination, respectively. The biological characterization of SYP-1620 against B. cinerea was determined in vitro. The results indicated that SYP-1620 has a strong inhibiting effect on spore germination, mycelial growth, and respiration. The protective and curative test of SYP-1620 suggested that protective effect was better than curative either on strawberry leaves or on cucumber leaves in vivo. In addition, the biological characterization of SYP-1620-resistant mutants of B. cinerea was investigated. SYP-1620 has no cross-resistance with other types of fungicide. Compared to the sensitive isolates, the resistant mutants had lower mycelial growth and virulence but not differ in mycelial dry weight. Sequencing indicated that SYP-1620 resistance was associated with a single point mutation (G143A) in the cytochrome b gene.

  9. New hosts of Myrothecium spp. in Brazil and a preliminary in vitro assay of fungicides

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    A.M. Quezado Duval

    2010-03-01

    Full Text Available Myrothecium roridum and M. verrucaria are two plant pathogenic species causing foliar spots in a large number of cultivated plants. This paper aims to study the causal agents of foliar spots in vegetable crops (sweet pepper, tomato and cucumber, ornamental plants (Spathiphyllum wallisii, Solidago canadensis, Anthurium andreanum, Dieffenbachia amoena and a solanaceous weed plant (Nicandra physaloides. Most of the isolates were identified as M. roridum; only the isolate 'Myr-02' from S. canadensis was identified as M. verrucaria. All the isolates were pathogenic to their original plant hosts and also to some other plants. Some fungicides were tested in vitro against an isolate of M. roridum and the mycelial growth recorded after seven days. Fungicides with quartenary ammonium, tebuconazole and copper were highly effective in inhibiting the mycelial growth of M. roridum. This paper confirms the first record of M. roridum causing leaf spots in sweet pepper, tomato, Spathiphyllum, Anthurium, Dieffenbachia and N. physaloides in Brazil. We also report M. roridum as causal agent of cucumber fruit rot and M. verrucaria as a pathogen of tango plants.

  10. Stemphylium Leaf Blight of Garlic (Allium sativum in Spain: Taxonomy and In Vitro Fungicide Response

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    Laura Gálvez

    2016-10-01

    Full Text Available The most serious aerial disease of garlic is leaf blight caused by Stemphylium spp. Geographical variation in the causal agent of this disease is indicated. Stemphylium vesicarium has been reported in Spain, whereas S. solani is the most prevalent species recorded in China. In this study, Stemphylium isolates were obtained from symptomatic garlic plants sampled from the main Spanish production areas. Sequence data for the ITS1–5.8S–ITS2 region enabled assignation of the isolates to the Pleospora herbarum complex and clearly distinguished the isolates from S. solani. Conidial morphology of the isolates corresponded to that of S. vesicarium and clearly discriminated them from S. alfalfae and S. herbarum on the basis of the size and septation pattern of mature conidia. Conidial morphology as well as conidial length, width and length:width ratio also allowed the Spanish isolates to be distinguished from S. botryosum and S. herbarum. Control of leaf blight of garlic is not well established. Few studies are available regarding the effectiveness of chemical treatments to reduce Stemphylium spp. incidence on garlic. The effectiveness of nine fungicides of different chemical groups to reduce Stemphylium mycelial growth in vitro was tested. Boscalid + pyraclostrobin (group name, succinate dehydrogenase inhibitors + quinone outside inhibitors, iprodione (dicar-boximide, and prochloraz (demethylation inhibitors were highly effective at reducing mycelial growth in S. vesicarium with EC₅₀ values less than 5 ppm. In general, the effectiveness of the fungicide was enhanced with increasing dosage.

  11. The mechanism of methyl mercury toxicity in isolated rat hepatocytes.

    Science.gov (United States)

    Ashour, H; Abdel-Rahman, M; Khodair, A

    1993-07-01

    Mercury is the major component of dental amalgam restorative material, which typically has 50% pure elemental mercury. It is also used in some skin creams, and in the manufacturing of plastic, drugs and fungicides. The present study was designed to investigate the toxicity of methyl mercury (MeHg+) on isolated rat hepatocytes using several toxicity parameters. The hepatocytes were isolated by a collagenase perfusion technique and were incubated with different concentrations of MeHg+ (0.1-100 ppm) for 2 h. Through the incubation period the viability was determined by Trypan blue exclusion. Reduced glutathione (GSH) content and its enzymes, glutathione peroxidase (GSH-PX) and glutathione reductase (GSH-RX) were measured. Leakage of enzymes such as aspartate transaminase (AST), and alanine transaminase (ALT) were determined. The cell viability was reduced significantly after 1 h incubation when 0.1 and 1 ppm MeHg+ were applied. The decrease in the cell viability was dose- and time-dependent. A depletion of GSH content was observed with 100 ppm MeHg+ after 30 min of incubation. A significant decrease in GSH-RX was observed with 100 ppm during 15 and 30 min of incubation, while 10 ppm of MeHg+ significantly increased ALT leakage after 60 min. However, there was a significant increase in AST leakage with 100 ppm only. The present investigation indicates that the toxic effect of MeHg+ is most likely cytosolic enzyme related.

  12. Sphaeropsidones, phytotoxic dimedone methyl ethers produced by Diplodia cupressi: a structure-activity relationship study.

    Science.gov (United States)

    Evidente, Antonio; Maddau, Lucia; Scanu, Bruno; Andolfi, Anna; Masi, Marco; Motta, Andrea; Tuzi, Angela

    2011-04-25

    Sphaeropsidone and episphaeropsidone are two phytotoxic dimedone methyl ethers produced by Diplodia cupressi, the causal agent of a canker disease of cypress in the Mediterranean area. In this study, eight derivatives obtained by chemical modifications and two natural analogues were assayed for phytotoxic and antifungal activities, and a structure-activity relationship was examined. Each compound was tested on nonhost plants and on five fungal pathogenic species belonging to the genus Phytophthora. The results provide insights into structure-activity relationships within these compounds. It was found that the hydroxy group at C-5, the absolute C-5 configuration, the epoxy group, and the C-2 carbonyl group appear to be structural features important in conferring biological activity. The conversion of sphaeropsidone into the corresponding 1,4-dione derivative led to a compound showing greater antifungal activity than its precursor. This finding could be useful in devising new natural fungicides for practical application in agriculture.

  13. Degradation of kresoxim-methyl in soil: impact of varying moisture, organic matter, soil sterilization, soil type, light and atmospheric CO2 level.

    Science.gov (United States)

    Khandelwal, Ashish; Gupta, Suman; Gajbhiye, Vijay T; Varghese, Eldho

    2014-09-01

    In the present investigation, persistence of kresoxim-methyl (a broad spectrum strobilurin fungicide) was studied in two different soil types of India namely Inceptisol and Ultisol. Results revealed that kresoxim-methyl readily form acid metabolite in soil. Therefore, residues of kresoxim-methyl were quantified on the basis of parent molecule alone and sum total of kresoxim-methyl and its acid metabolite. Among the two soil types, kresoxim-methyl and total residues dissipated at a faster rate in Inceptisol (T1/2 0.9 and 33.8d) than in Ultisol (T1/2 1.5 and 43.6d). Faster dissipation of kresoxim-methyl and total residues was observed in submerged soil conditions (T1/2 0.5 and 5.2d) followed by field capacity (T1/2 0.9 and 33.8d) and air dry (T1/2 2.3 and 51.0d) conditions. Residues also dissipated faster in 5% sludge amended soil (T1/2 0.7 and 21.1d) and on Xenon-light exposure (T1/2 0.5 and 8.0d). Total residues of kresoxim-methyl dissipated at a faster rate under elevated CO2 condition (∼550μLL(-)(1)) than ambient condition (∼385μLL(-)(1)). The study suggests that kresoxim-methyl alone has low persistence in soil. Because of the slow dissipation of acid metabolite, the total residues (kresoxim-methyl+acid metabolite) persist for a longer period in soil. Statistical analysis using SAS 9.3 software and Duncan's Multiple Range Test (DMRT) revealed the significant effect of moisture regime, organic matter, microbial population, soil type, light exposure and atmospheric CO2 level on the dissipation of kresoxim-methyl from soil (at 95% confidence level p<0.0001). Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Toxic effects of three strobilurins (trifloxystrobin, azoxystrobin and kresoxim-methyl) on mRNA expression and antioxidant enzymes in grass carp (Ctenopharyngodon idella) juveniles.

    Science.gov (United States)

    Liu, Lei; Jiang, Chao; Wu, Zhuo-Qi; Gong, Yu-Xin; Wang, Gao-Xue

    2013-12-01

    The strobilurins are used widely in the world as effective fungicidal agents to control Asian soybean rust. In this study, the early life stage of grass carp (Ctenopharyngodon idella), which is one of the most important aquaculture species in China, was chosen to measure the acute toxicity of three common strobilurin-derived fungicides (trifloxystrobin (TFS), azoxystrobin (AZ) and kresoxim-methyl (KM)). As endpoints, normal developmental parameters (lethal concentration (LC₅₀) and average heart rate), expression of relative genes, and three antioxidant enzyme activities in the developing juveniles were recorded during a 48 h exposure. The results revealed that values of LC₅₀ were TFS 0.051 (0.046-0.058) mg L⁻¹, AZ 0.549 (0.419-0.771) mg L⁻¹ and KM 0.338 (0.284-0.407) mg L⁻¹ for juveniles. For the potential toxicity mechanisms, these three fungicides increased catalase (CAT) and peroxidase (POD) activity and decreased superoxide dismutase (SOD) activity, significantly inhibited expressions of three growth-related genes (IGF-1, IGF-2 and GHR) and two energy-related-genes (CCK and PYY), and caused pronounced up-regulation a stress-gene (HSP70). The present study demonstrated potential toxic effects of TFS, AZ and KM on the early development of C. idella. Overall, three strobilurins (TFS, AZ and KM) might cause serious damages to the aquatic species; therefore, their pollution supervision in water ecological environment should be strengthened.

  15. Fungicide sensitivity of US genotypes of Phytophthora infestans (Mont.) de Bary to six oomycete-targeted compounds.

    Science.gov (United States)

    Phytophthora infestans (Mont.) de Bary causes potato late blight, an important and costly disease of potato and tomato crops. The baseline sensitivity of recent clonal lineages of P. infestans was tested for six oomycete-targeted fungicides. Forty five isolates collected between 2004 and 2012 were t...

  16. Selection of candidate genes involved in the defense mechanisms of Phytophthora infestans against fungicides by EST analysis

    Science.gov (United States)

    Preliminary research using a functional genomics approach was conducted to gain insights on how P. infestans responds to fungicides and the possible implications of these responses on its ability to adapt to such selection pressure. Two isolates with subtle differences in mefenoxam resistance were e...

  17. Control of citrus postharvest green mold and sour rot by potassium sorbate combined with heat and fungicides

    Science.gov (United States)

    Potassium sorbate (KS), a common food preservative, was evaluated to control postharvest decay of citrus fruit. Significant advantages of KS over the commonly used sodium bicarbonate, which similarly improved fungicide performance, are the relatively low salt concentration of KS, the absence of sodi...

  18. Multiple mechanisms account for variation in base-line sensitivity to azole fungicides in field isolates of Mycosphaerella graminicola

    NARCIS (Netherlands)

    Stergiopoulos, I.; Nistelrooy, van J.G.M.; Kema, G.H.J.; Waard, de M.A.

    2003-01-01

    Molecular mechanisms that account for variation in base-line sensitivity to azole fungicides were examined in a collection of twenty field isolates, collected in France and Germany, of the wheat pathogen Mycosphaerella graminicola (Fuckel) Schroeter. The isolates tested represent the wide base-line

  19. Fungicide-driven evolution and molecular basis of multidrug resistance in field populations of the grey mould fungus Botrytis cinerea

    NARCIS (Netherlands)

    Kretschmer, M.; Leroch, M.; Mosbach, A.; Walker, A.S.; Fillinger, S.; Mernke, D.; Schoonbeek, H.J.; Pradier, J.M.; Leroux, P.; Waard, de M.A.; Hahn, M.

    2009-01-01

    The grey mould fungus Botrytis cinerea causes losses of commercially important fruits, vegetables and ornamentals worldwide. Fungicide treatments are effective for disease control, but bear the risk of resistance development. The major resistance mechanism in fungi is target protein modification res

  20. Limited fungicide applications affect foliar and fruit disease severity and phytochemical content of muscadine grape (Vitis rotundifolia Michx.)

    Science.gov (United States)

    Berry rot diseases cause significant reductions in yield and quality of muscadine grapes, but these losses may be reduced significantly by fungicide applications. Four studies were conducted to explore the relationship between yield, disease control, berry quality, and phytochemical content followin...