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Sample records for reduced glyphosate sensitivity

  1. Resposta de cultivares de algodoeiro a subdoses de glyphosate Response of cotton cultivars to reduced rates of glyphosate

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    O.M. Yamashita

    2005-12-01

    Full Text Available Avaliou-se a resposta de nove cultivares de algodoeiro, de importância econômica no Estado do Mato Grosso, quanto à intoxicação causada por subdoses de glyphosate. Os cultivares de algodoeiro utilizados foram Fabrika, Makina, ITA-90, FM 986, FM 966, Delta Opal, BRS Facual, Antares e Coodetec 407. As plantas foram cultivadas em tubetes preenchidos com substrato de solo e mantidas em casa telada, tendo recebido a aplicação do glyphosate aos 20 dias após a emergência, época em que apresentavam quatro folhas verdadeiras. As subdoses de glyphosate, simulando deriva, foram de 270 e 540 g ha-1. Também foi utilizada testemunha, sem aplicação do herbicida, para efeito de comparação. Foram realizadas avaliações semanais até 42 dias após a aplicação dos tratamentos (DAA, período em que também foi tomada a altura das plantas. Os sintomas visuais de intoxicação iniciaram-se aos 3 DAA, caracterizados pelo amarelecimento das pontas das folhas mais novas, seguido de murchamento do ápice das plantas. Na dose de 270 g ha-1 esses sintomas foram de baixa intensidade, mas a 540 g ha-1 causaram, na maioria dos casos, toxidez "preocupante" a "muito alta". Os cultivares BRS Facual e FM 986 mostraram-se os mais suscetíveis. A altura das plantas foi mais afetada quando se aplicou a menor dose de glyphosate. Houve recuperação de todos os cultivares tratados com 270 g ha-1 de glyphosate até os 42 DAA. Quando tratados com 540 g ha-1 de glyphosate, os cultivares Fabrika, Coodetec 407, BRS-Facual e ITA-90 foram mais sensíveis, apresentando redução de altura entre 84 e 90% aos 42 DAA. Os cultivares menos sensíveis na dose de 270 g ha-1 de glyphosate não foram os mesmos para a dose de 540 g ha-1.The response of nine cotton cultivars economically important in the state of Mato Grosso was evaluated in relation to the toxicity caused by reduced rates of glyphosate. The cotton cultivars used were Fabrika, Makina, ITA-90, FM 986, FM 966, Delta Opal, BRS Facual, Antares and Coodetec 407. The plants were cultivated in plastic pots filled with soil substratum and kept under greenhouse conditions. Glyphosate application was performed 20 days post emergence, at which time they presented four true leaves. Reduced rates of glyphosate, simulating drift, ranged from 270 and 540 g. A control was also used, without herbicide application to compare the effects. Weekly evaluations were accomplished up to 42 days after application (DAA. During this period, plant height was also measured. Visual symptoms began 3 DAA, with the appearance of yellow spots at the tips of the youngest leaves, followed by withering at the apex of the plants. At the rate of 270 g ha-1, these symptoms showed low intensity but at the rate of 540 g ha-1 the symptoms caused "worrisome" to "very high'' toxicity, in most of the cases. BRS Facual and FM 986 were the most susceptible. Plant height was the most affected when the lowest glyphosate dose was applied. All cultivars treated with 270 g ha-1 glyphosate rate until 42 DAA were recovered. Fabrika, Coodetec 407, BRS Facual and ITA-90 cultivars, when treated with 540 g ha-1 glyphosate were more sensitive, presenting a height reduction between 84 and 90% 42 DAA. The less sensitive cultivars at the rate of 270 g ha-1 glyphosate were not the same at the 540 g ha-1 rate.

  2. Glyphosate spray drift in Coffea arabica - sensitivity of coffee plants and possible use of shikimic acid as a biomarker for glyphosate exposure.

    Science.gov (United States)

    Schrübbers, Lars C; Valverde, Bernal E; Sørensen, Jens C; Cedergreen, Nina

    2014-10-01

    Glyphosate is widely used in coffee plantations to control weeds. Lacking selectivity, glyphosate spray drift is suspected to cause adverse effects in coffee plants. Symptoms caused by glyphosate can be similar to those produced by other stress factors. However, shikimic acid accumulation should be a useful biomarker for glyphosate exposure as shown for other crops. The aim of this study was to assess the sensitivity of coffee plants towards glyphosate on different biological response variables and to evaluate the use of shikimic acid as biomarker. Dose-response experiments yielded ED50 values (50% effect dose) in the range of 38-550 ga.e.ha(-1) depending on the quantitative or qualitative variable monitored. The frequency of plants showing symptoms was the most sensitive variable. The best sampling time for shikimic acid accumulation was 1-2 weeks after glyphosate application, depending on experimental conditions. The highest shikimic acid accumulation was observed in young leaves. Shikimic acid is a suitable biomarker for a glyphosate exposure in coffee, using only young leaves for the analysis. Young coffee plants are susceptible to glyphosate damage. If symptoms are absent the risk of severe crop damage or yield loss is low. PMID:25307461

  3. Addition of pH reducers and rates of glyphosate in the weeds desiccation

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    Miriam Hiroko Inoue

    2007-04-01

    Full Text Available Two experiments were conducted to evaluate the influence from the addition of pH reducers and rates of glyphosate in the spray mix to Euphorbia heterophylla and Glycine max control. The treatments were arranged in a factorial scheme (4 x 2 + 1, randomized blocks design and four replications. Each experiment used a pH reducer (pH Fós ou Redumax, four rates of reducer (0, 50, 75 and 100% of the rate recommended, two rates of glyphosate (450 and 900 g ha-1 and an untreated check. The weed control was evaluated at 4, 6, 8, 10, 12 and 14 days after application (DAA of treatments, in visual scale from 0 to 100% of control. In both experiments, 450 g ha-1 glyphosate, the addition of reducers in the spray mix provided greater weed control in relation to only glyphosate. There was no difference in 50, 75 and 100% of the rate recommended of reducers. With the use of adjuvant has a satisfactory control with half the recommended rate of glyphosate at 14 DAA. These results demonstrate the possibility of reduced rates of glyphosate when used these adjuvants in the spray mix.

  4. Anatomia foliar de Lolium multiflorum sensível e resistente ao glyphosate / Leaf anatomy of Lolium multiflorum sensitive and resistant to glyphosate

    Scientific Electronic Library Online (English)

    J., Galvani; M.A., Rizzardi; C.M., Carneiro; M.A, Bianchi.

    2012-06-01

    Full Text Available Este trabalho foi desenvolvido com o intuito de contribuir para o conhecimento anatômico da espécie Lolium multiflorum e, a partir disso, observar possíveis alterações que possam elucidar o mecanismo que confere resistência ao herbicida glyphosate. Para isso, realizou-se um experimento com quatro bi [...] ótipos dessa espécie com distinta sensibilidade ao herbicida glyphosate, sendo um sensível (B1S) e três resistentes (B2R, B3R e B4R). As análises ocorreram a partir de secções transversais e longitudinais dos órgãos vegetativos de plantas no estádio de afilhamento. Anatomicamente, o azevém caracteriza-se por apresentar grande quantidade de estômatos e de células buliformes, bem como mesofilo homogêneo constituído apenas de células paliçádicas compactamente distribuídas. Comparativamente, não ocorrem diferenças morfológicas evidentes que possam ser usadas para diferir biótipos sensíveis de resistentes, no entanto, nota-se que biótipos resistentes, especialmente B3R e B4R, apresentaram maior densidade estomática em relação aos demais. Ainda, os biótipos resistentes apresentaram maior quantidade de espaços intercelulares no mesofilo e feixes vasculares com menor quantidade de floema em relação ao xilema, o que, por suas funções na planta, pode colaborar para a menor sensibilidade ao herbicida. Abstract in english This work aimed to contribute to the anatomical knowledge of the species Lolium multiflorum and to observe possible changes that may elucidate the mechanism that confers its resistance to the herbicide glyphosate. Thus, an experiment was conducted using four biotypes of this species with distinct se [...] nsitivities to the herbicide glyphosate: one susceptible (B1S) and three resistant biotypes (B2R, B3R and B4R). Analyses were conducted on the transverse and longitudinal sections of the vegetative organs of the plants at the tillering stage. Anatomically, ryegrass is characterized as having a large number of stomata and buliform cells as well as homogeneous mesophylls constituted only of palisade cells compactly distributed. Comparatively, no evident morphological differences occur that can be used to distinguish sensitive from resistant biotypes; however, the resistant biotypes, especially B3R B4R, presented higher stomatal density, compared to the others. Still, the resistant biotypes had a higher amount of intercellular spaces in the mesophyll and vascular bundles with a smaller amount of phloem compared to the xylem, which, because of their functions in the plants, may contribute to the lower sensitivity to the herbicide.

  5. Influência de doses reduzidas do glyphosate no tomateiro (Lycopersicon esculentum Influence of reduced glyphosate rates on tomato plant (Lycopersicon esculentum Mill.

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    S.S. Fiqueredo

    2007-12-01

    Full Text Available O tomateiro (Lycopersicon esculentum é cultivado em todas as regiões do Brasil devido à ampla utilização na culinária, tanto in natura quanto industrializado. A deriva do glyphosate vem sendo citada como um dos fatores que interferem negativamente sobre as culturas hortícolas, cultivadas nas adjacências das lavouras de arroz. Objetivou-se com esse verificar os efeitos de doses reduzidas do glyphosate sobre a cultura do tomateiro. O glyphosate foi aplicado a 0, 15, 30, 45, 60, 75 e 90% da dose de 1.260 g ha-1, aos 30, 50 e 70 dias após o transplante (DAT da cultura. As variáveis analisadas foram fitotoxicidade, altura e número de cachos florais, flores e frutos por planta. Os dados experimentais foram submetidos à análise da variância e, sendo significativos, os efeitos de época de aplicação foram comparados pelo teste de Tukey, e os efeitos do fator dose, analisados por regressão. A aplicação do glyphosate, a partir de 378 g ha-1, afetou o desenvolvimento do tomateiro, independentemente do estádio de desenvolvimento.Tomato plant (Lycopersicon esculentum is grown in all regions in Brazil since it is widely used in cooking, processed or fresh. Glyphosate drift has been found rcited as one of the factors interfering negatively in vegetables cultivated in areas adjacent to rice plantations. The objective of this study was to evaluate the effects of reduced rates of glyphosate on tomato plants, applied at of 0, 15, 30, 45, 60, 75 and 90% of the commercial dose (1.260 g ha-1 30, 50 and 70 days after transplanting (DAT the tomato plants. The variables analyzed were: phytotoxicity, plant height, number of flowering clusters, and flower and fruits/plant. The data were submitted to analysis of variance, the Tukey test and regression. Glyphosate application at rates higher than 378 g ha-1 affected the growth of the tomato plants negatively, regardless of their development stage.

  6. Efeito de doses reduzidas de glyphosate e paraquat simulando deriva na cultura do milho Effect of reduced rates of glyphosate and paraquat simulating drift in corn crop

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    P.C. Magalhães

    2001-08-01

    Full Text Available A aplicação de herbicidas, seja para a dissecação de culturas ou para o controle de plantas daninhas, vem crescendo, devido a expansão da fronteira agrícola brasileira. Esse fato aumenta os riscos de ocorrência de deriva acidental em culturas vizinhas suscetíveis. As perdas em produtividade são desconhecidas em muitas situações de ocorrência de deriva de herbicidas. O objetivo deste trabalho foi avaliar a possível toxicidade causada pela deriva de doses reduzidas de dois herbicidas (glyphosate e paraquat no período inicial de desenvolvimento da cultura do milho. Foram utilizadas cinco doses simulando deriva - 2, 4, 6, 8 e 12% da dose recomendada (1.440 g ha-1 de glyphosate e 400 g ha-1 de paraquat - sobre o cultivar de milho híbrido triplo BRS 3123. No florescimento, foram avaliados altura da planta, área foliar, peso da matéria seca, teor de clorofila e sintomas visuais de injúria. Na colheita, avaliaram-se estande final, peso de espigas, peso de 1.000 grãos e produção de grãos. A altura das plantas, a área foliar e o peso da matéria seca não foram afetados pelo efeito das derivas nos dois anos agrícolas (1996/97 e 1997/98, exceto pela área foliar, que em 1997/98 sofreu redução, sobretudo no tratamento com 12% da dose normal de glyphosate. De maneira geral, os resultados obtidos para as demais características foram semelhantes nos dois anos de condução do ensaio. O teor de clorofila nas folhas e o estande final não foram afetados pelas doses reduzidas. O grau de toxicidade, avaliado por meio de plantas injuriadas pela deriva, aos 7, 14 e 21 dias após a aplicação dos herbicidas, apresentou diferenças significativas. Os maiores danos foram observados com a maior subdose simulando deriva dos herbicidas. O peso de 1.000 grãos não foi afetado, ao passo que a produção de espigas e de grãos foi severamente prejudicada. Observou-se que a deriva simulada dos herbicidas em altas concentrações afetou o desenvolvimento das plantas e reduziu a produção de grãos. Já a aplicação em baixas concentrações (2 a 4% não afetou o desenvolvimento das plantas nem tampouco a produtividade.Herbicide application has increased considerably in the Brazilian agriculture over the last years, either for weed management or crop desiccation. The intensive use of herbicide shas brought risks of drift in sensitive neighbor crops. Drift effects on crops susceptible to herbicides is not well quantified in several situations. The objective of this study was to evaluate the injuries caused by simulated herbicide drift on the initial phase of growth of the maize crop. Two herbicides with five concentrations of simulated drift were used: 2, 4, 6, 8 and 12% of the recommended rate (1,440 g ha-1 of glyphosate and 400 g ha-1 of paraquat, sprayed over the top foliage of the maize triple hybrid BRS 3123. Plant height, leaf area, dry weight, leaf chlorophyll content and visual symptoms of injury were evaluated at flowering time. Final stand, ear weight, 1,000 grains weight and grain production. Plant height, leaf area, leaf chlorophyll content and dry weight were not affected by simulated drifts in both years (1996/97 and 1997/98, except the leaf area in 1997/98, which had a reduction especially in the treatment where 12% of the glyphosate rate was used. In general, the results for the other traits were similar in both years in which the trials were carried out. At harvesting time, final stand and weight of 1,000 grains were not affected by simulated drifts, whereas ear weight and grain production were severely affected. The degree of visual injuries evaluated through percentage of plants injured by drift at 7, 14 and 21 days after herbicide application showed significant differences. The major damages were observed with the greater dosage of simulated drift. Weight of 1,000 grains was not affected, whereas ears and grain production were severely affected. Herbicide drift in high concentrations affected the plant development and reduced grain production while application of glyphosate and paraqu

  7. Resposta de varjão (Parkia multijuga a subdoses de glyphosate Response of varjão (Parkia multijuga seedlings to reduced glyphosate rates

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    O.M. Yamashita

    2006-09-01

    Full Text Available O consumo de madeira no Brasil e no mundo apresenta demanda crescente. Em confronto com a pressão ambientalista de manutenção das florestas nativas, há necessidade de se estabelecerem áreas de reflorestamento para suprir o aumento da demanda de madeira, com a utilização de formas de manejo e tratos culturais que permitam o pleno crescimento das essências florestais. Um dos principais problemas do manejo de reflorestamento é a interferência das plantas daninhas após o plantio das mudas no campo, sendo o uso de herbicidas a principal forma de manejo. Este trabalho teve o objetivo de avaliar a eficiência de doses crescentes de glyphosate em mudas de varjão em condições de ambiente protegido. Foram avaliadas as doses de 0, 90, 180, 360 e 720 g ha-1 de glyphosate em plantas com quatro meses de idade, observando a intoxicação das plantas, altura, diâmetro do caule e número de folhas. O varjão, nas condições do experimento, apresentou tolerância e recuperação ao glyphosate até a dose de 360 g ha-1. Doses superiores a esta retardaram o crescimento da planta. O prejuízo causado pela deriva de glyphosate nessas plantas foi diretamente proporcional ao aumento da dose. Os sintomas evoluíram para queda de folhas, comprometendo o crescimento das plantas.Wood consumption has significantly increased in Brazil and worldwide.The environmental pressure to preserve native forest led to the need to establish reforestation areas to meet the increasing wood demand by applying cultural practices and management allowing a total growth of forest trees. One of the main problems in reforestation management is weed competition after seedling planting, with herbicide use being the main form of management. The objective of this work was to evaluate the phytotoxic effect of increasing rates of glyphosate on Varjão seedlings, under greenhouse conditions. Concentrations of 90, 180, 360 and 720 g ha-1 of glyphosate were evaluated in four-month-old plants by observing plant toxicity, plant height, stem diameter, and leaf number. A control was also used without herbicide application to compare the effects. Under the conditions of this experiment, Varjão presented tolerance to and ability to recover from glyphosate up to the rate of 360 g ha-1. Higher rates delayed plant development. The damage caused by glyphosate drift in these plants was directly proportional to rate increase. The symptoms included leaf fall, compromising plant growth.

  8. Efeito de doses reduzidas de glyphosate e paraquat simulando deriva na cultura do milho / Effect of reduced rates of glyphosate and paraquat simulating drift in corn crop

    Scientific Electronic Library Online (English)

    P.C., Magalhães; J.B., Silva; F.O.M., Durães; D., Karam; L.S., Ribeiro.

    2001-08-01

    Full Text Available A aplicação de herbicidas, seja para a dissecação de culturas ou para o controle de plantas daninhas, vem crescendo, devido a expansão da fronteira agrícola brasileira. Esse fato aumenta os riscos de ocorrência de deriva acidental em culturas vizinhas suscetíveis. As perdas em produtividade são desc [...] onhecidas em muitas situações de ocorrência de deriva de herbicidas. O objetivo deste trabalho foi avaliar a possível toxicidade causada pela deriva de doses reduzidas de dois herbicidas (glyphosate e paraquat) no período inicial de desenvolvimento da cultura do milho. Foram utilizadas cinco doses simulando deriva - 2, 4, 6, 8 e 12% da dose recomendada (1.440 g ha-1 de glyphosate e 400 g ha-1 de paraquat) - sobre o cultivar de milho híbrido triplo BRS 3123. No florescimento, foram avaliados altura da planta, área foliar, peso da matéria seca, teor de clorofila e sintomas visuais de injúria. Na colheita, avaliaram-se estande final, peso de espigas, peso de 1.000 grãos e produção de grãos. A altura das plantas, a área foliar e o peso da matéria seca não foram afetados pelo efeito das derivas nos dois anos agrícolas (1996/97 e 1997/98), exceto pela área foliar, que em 1997/98 sofreu redução, sobretudo no tratamento com 12% da dose normal de glyphosate. De maneira geral, os resultados obtidos para as demais características foram semelhantes nos dois anos de condução do ensaio. O teor de clorofila nas folhas e o estande final não foram afetados pelas doses reduzidas. O grau de toxicidade, avaliado por meio de plantas injuriadas pela deriva, aos 7, 14 e 21 dias após a aplicação dos herbicidas, apresentou diferenças significativas. Os maiores danos foram observados com a maior subdose simulando deriva dos herbicidas. O peso de 1.000 grãos não foi afetado, ao passo que a produção de espigas e de grãos foi severamente prejudicada. Observou-se que a deriva simulada dos herbicidas em altas concentrações afetou o desenvolvimento das plantas e reduziu a produção de grãos. Já a aplicação em baixas concentrações (2 a 4%) não afetou o desenvolvimento das plantas nem tampouco a produtividade. Abstract in english Herbicide application has increased considerably in the Brazilian agriculture over the last years, either for weed management or crop desiccation. The intensive use of herbicide shas brought risks of drift in sensitive neighbor crops. Drift effects on crops susceptible to herbicides is not well quan [...] tified in several situations. The objective of this study was to evaluate the injuries caused by simulated herbicide drift on the initial phase of growth of the maize crop. Two herbicides with five concentrations of simulated drift were used: 2, 4, 6, 8 and 12% of the recommended rate (1,440 g ha-1 of glyphosate and 400 g ha-1 of paraquat), sprayed over the top foliage of the maize triple hybrid BRS 3123. Plant height, leaf area, dry weight, leaf chlorophyll content and visual symptoms of injury were evaluated at flowering time. Final stand, ear weight, 1,000 grains weight and grain production. Plant height, leaf area, leaf chlorophyll content and dry weight were not affected by simulated drifts in both years (1996/97 and 1997/98), except the leaf area in 1997/98, which had a reduction especially in the treatment where 12% of the glyphosate rate was used. In general, the results for the other traits were similar in both years in which the trials were carried out. At harvesting time, final stand and weight of 1,000 grains were not affected by simulated drifts, whereas ear weight and grain production were severely affected. The degree of visual injuries evaluated through percentage of plants injured by drift at 7, 14 and 21 days after herbicide application showed significant differences. The major damages were observed with the greater dosage of simulated drift. Weight of 1,000 grains was not affected, whereas ears and grain production were severely affected. Herbicide drift in high concentrations affected the plant development and reduced grain production w

  9. TREATABILITY STUDIES OF PESTICIDE MANUFACTURING WASTEWATERS: GLYPHOSATE

    Science.gov (United States)

    The report gives results of subjecting various combinations of glyphosate production wastestreams to biological treatment following lime-pretreatment to reduce high levels of glyphosate. Bench-scale biological treatment demonstrated that glyphosate did not appear to interfere wit...

  10. Birch (Betula spp.) wood biochar is a potential soil amendment to reduce glyphosate leaching in agricultural soils.

    Science.gov (United States)

    Hagner, Marleena; Hallman, Sanna; Jauhiainen, Lauri; Kemppainen, Riitta; Rämö, Sari; Tiilikkala, Kari; Setälä, Heikki

    2015-12-01

    Glyphosate (N-(phosphonomethyl) glycine), a commonly used herbicide in agriculture can leach to deeper soil layers and settle in surface- and ground waters. To mitigate the leaching of pesticides and nutrients, biochar has been suggested as a potential soil amendment due to its ability to sorb both organic and inorganic substances. However, the efficiency of biochar in retaining agro-chemicals in the soil is likely to vary with feedstock material and pyrolysis conditions. A greenhouse pot experiment, mimicking a crop rotation cycle of three plant genera, was established to study the effects of pyrolysis temperature on the ability of birch (Betula sp.) wood originated biochar to reduce the leaching of (i) glyphosate, (ii) its primary degradation product AMPA and (iii) phosphorus from the soil. The biochar types used were produced at three different temperatures: 300 °C (BC300), 375 °C (BC375) and 475 °C (BC475). Compared to the control treatment without biochar, the leaching of glyphosate was reduced by 81%, 74% and 58% in BC300, BC375 and BC475 treated soils, respectively. The respective values for AMPA were 46%, 39% and 23%. Biochar had no significant effect on the retention of water-soluble phosphorus in the soil. Our results corroborate earlier findings on pesticides, suggesting that biochar amendment to the soil is a promising way to reduce also the leaching of glyphosate. Importantly, the ability of biochar to adsorb agro-chemicals depends on the temperature at which feedstock is pyrolysed. PMID:26342266

  11. In-Crop and Autumn-Applied Glyphosate Reduced Purple Nutsedge (Cyperus rotundus)Density in No-Till Glyphosate-Resistant Corn and Soybean

    Science.gov (United States)

    A 3-yr field study was conducted from 2005 to 2007 at Stoneville, MS to determine efficacy of in-crop and fall-applied glyphosate on purple nutsedge density and yield of no-till glyphosate-resistant (GR) corn and GR soybean. Separate experiments were conducted in GR corn and GR soybean in areas main...

  12. Lanolin of reduced sensitizing potential.

    Science.gov (United States)

    Clark, E W; Blondeel, A; Cronin, E; Oleffe, J A; Wilkinson, D S

    1981-03-01

    Confirmation has been obtained that reducing the content of natural free alcohols in lanolin to below 3%, particularly in the absence of detergent residues, reduces the incidence of positive patch test reactions amongst selected lanolin-sensitive skin patients by 99.3%. Only one reaction out of 149 subjects was recorded. PMID:7238016

  13. Sensitivity of imidazolinone-resistant red rice (Oryza sativa L.) to glyphosate and glufosinate / Sensibilidade de arroz-vermelho (Oryza sativa L.) resistente às imidazolinonas, aos herbicidas glyphosate e glufosinate

    Scientific Electronic Library Online (English)

    Guilherme Vestena, Cassol; Luis Antonio de, Avila; Carla Rejane, Zemolin; Andrey, Piveta; Dirceu, Agostinetto; Aldo, Merotto Júnior.

    Full Text Available Curvas de dose-resposta foram conduzidas para avaliar a sensibilidade de arroz-vermelho resistente às imidazolinonas para herbicidas não-seletivos, comumente utilizados em áreas de rotação soja-arroz irrigado no Rio Grande do Sul. Dois biótipos de arroz-vermelho, previamente identificados como susce [...] tível e resistente às imidazolinonas, foram aspergidos com imazapyr+imazapic, glyphosate e glufosinate sob nove concentrações herbicidas. Utilizou-se análise de regressão não linear do tipo log-logística para estimar a concentração herbicida que proporcionou 50% de controle e redução na massa de matéria seca da parte aérea (GR50) de arroz-vermelho. O biótipo de arroz-vermelho resistente às imidazolinonas demonstrou maior GR50, quando comparado ao biótipo suscetível para imazapyr+imazapic. Valores similares de GR50 foram observados para ambos os biótipos tratados com glyphosate e glufosinate. Esses resultados indicam que os herbicidas glyphosate e glufosinate controlam efetivamente biótipos de arroz-vermelho resistente às imidazolinonas em doses recomendadas para controlar biótipos suscetíveis às imidazolinonas. No entanto, práticas integradas de manejo devem ser utilizadas para retardar a evolução da resistência de arroz-vermelho aos herbicidas glyphosate e glufosinate na rotação soja-arroz irrigado Abstract in english Dose-response experiments were carried out to evaluate the sensitivity of imidazolinone-resistant red rice to nonselective herbicides currently used in rice-soybean rotation in Rio Grande do Sul. Two red rice biotypes previously identified as resistant and susceptible to the imidazolinone herbicides [...] were treated with imazapic plus imazapic, glyphosate and glufosinate under nine herbicide rates. A non-linear log-logistic analysis was used to estimate the herbicide rate that provided 50% red rice control and dry weight reduction (GR50). Imidazolinone-resistant red rice exhibited greater GR50 values than imidazolinone-susceptible biotype for imazapyr plus imazapic. In contrast, both imidazolinone-resistant and susceptible red rice showed similar GR50 values for glyphosate and glufosinate. These results indicate that glyphosate and glufosinate effectively control imidazolinone-resistant red rice at similar herbicide rates used to control imidazolinone-susceptible; however, integrated weed management practices must be adopted in rice-soybean rotation to delay resistance evolution of red rice populations to glyphosate and glufosinate

  14. Glyphosate-resistant goosegrass. Identification of a mutation in the target enzyme 5-enolpyruvylshikimate-3-phosphate synthase.

    Science.gov (United States)

    Baerson, Scott R; Rodriguez, Damian J; Tran, Minhtien; Feng, Yongmei; Biest, Nancy A; Dill, Gerald M

    2002-07-01

    The spontaneous occurrence of resistance to the herbicide glyphosate in weed species has been an extremely infrequent event, despite over 20 years of extensive use. Recently, a glyphosate-resistant biotype of goosegrass (Eleusine indica) was identified in Malaysia exhibiting an LD(50) value approximately 2- to 4-fold greater than the sensitive biotype collected from the same region. A comparison of the inhibition of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity by glyphosate in extracts prepared from the resistant (R) and sensitive (S) biotypes revealed an approximately 5-fold higher IC(50)(glyphosate) for the (R) biotype. Sequence comparisons of the predicted EPSPS mature protein coding regions from both biotypes revealed four single-nucleotide differences, two of which result in amino acid changes. One of these changes, a proline to serine substitution at position 106 in the (R) biotype, corresponds to a substitution previously identified in a glyphosate-insensitive EPSPS enzyme from Salmonella typhimurium. Kinetic data generated for the recombinant enzymes suggests that the second substitution identified in the (R) EPSPS does not contribute significantly to its reduced glyphosate sensitivity. Escherichia coli aroA- (EPSPS deficient) strains expressing the mature EPSPS enzyme from the (R) biotype exhibited an approximately 3-fold increase in glyphosate tolerance relative to strains expressing the mature EPSPS from the (S) biotype. These results provide the first evidence for an altered EPSPS enzyme as an underlying component of evolved glyphosate resistance in any plant species. PMID:12114580

  15. Evaluation of 2,4-D Amine, Glyphosate, 2,4-D Amine plus Glyphosate DMA and 2,4-D Choline/Glyphosate DMA for Their Efficacy on Glyphosate Susceptible and Resistant Canada Fleabane Populations

    OpenAIRE

    Laura Ford; Nader Soltani; Robinson, Darren E.; Robert E. Nurse; Allan McFadden; Peter H. Sikkema

    2014-01-01

    The 2,4-D choline/glyphosate DMA formulation has reduced drift and volatility compared to the amine or ester formulation of 2,4-D and therefore is advantageous compared to a tank mix of 2,4-D amine or ester with glyphosate. The objective of this research was to compare the control of glyphosate susceptible and glyphosate resistant Canada fleabane with 2,4-D choline/glyphosate DMA with 2,4-D amine, glyphosate, and a tank mix of 2,4-D amine and glyphosate. Ten rates of 2,...

  16. Glyphosate-based herbicides reduce the activity and reproduction of earthworms and lead to increased soil nutrient concentrations.

    Science.gov (United States)

    Gaupp-Berghausen, Mailin; Hofer, Martin; Rewald, Boris; Zaller, Johann G

    2015-01-01

    Herbicide use is increasing worldwide both in agriculture and private gardens. However, our knowledge of potential side-effects on non-target soil organisms, even on such eminent ones as earthworms, is still very scarce. In a greenhouse experiment, we assessed the impact of the most widely used glyphosate-based herbicide Roundup on two earthworm species with different feeding strategies. We demonstrate, that the surface casting activity of vertically burrowing earthworms (Lumbricus terrestris) almost ceased three weeks after herbicide application, while the activity of soil dwelling earthworms (Aporrectodea caliginosa) was not affected. Reproduction of the soil dwellers was reduced by 56% within three months after herbicide application. Herbicide application led to increased soil concentrations of nitrate by 1592% and phosphate by 127%, pointing to potential risks for nutrient leaching into streams, lakes, or groundwater aquifers. These sizeable herbicide-induced impacts on agroecosystems are particularly worrisome because these herbicides have been globally used for decades. PMID:26243044

  17. Variabilidade genética e sensibilidade de acessos de Pistia stratiotes ao herbicida glyphosate Genetic variability and sensitivity of Pistia stratiotes accesses to glyphosate

    Directory of Open Access Journals (Sweden)

    E.A.S. Cícero

    2007-09-01

    Full Text Available A alface-d'água (Pistia stratiotes é uma das principais entre as macrófitas aquáticas que causam problemas em corpos hídricos no Brasil e são consideradas como plantas daninhas. O presente trabalho foi realizado com os objetivos de conhecer melhor a variabilidade genética dessa macrófita e relacionar essa variabilidade com a resposta à aplicação do herbicida glyphosate. Para isso, foram coletados indivíduos em 12 corpos hídricos em diferentes cidades do território nacional (Americana, Cambaratiba, Curitiba, Itapura, Jaboticabal, Lagoa Santa, Piraí, Rio Grande, Rubinéia, Salto Grande, Santa Gertrudes e Três Lagoas. Os acessos foram caracterizados pelo uso de marcadores RAPD (DNA Polimórfico Amplificado ao Acaso, que permitiram, com o auxílio de iniciadores aleatórios, a caracterização dos locos polimórficos identificados por uma matriz de ausência e presença de bandas. Utilizando essa matriz, a análise de agrupamento permitiu nítida classificação dos acessos em três grupos com diferenças genéticas entre eles. Um ensaio de controle químico, com plantas mantidas em vasos plásticos (5 L e pulverizadas com o herbicida glyphosate nas concentrações de 0,0, 0,6, 1,2, 1,8 e 2,4 kg ha-1, identificou, utilizando avaliações aos 7, 14 e 21 dias após aplicação, que as duas maiores doses promoveram melhor efeito herbicida. Foi verificado também que os acessos de Curitiba e Cambaratiba apresentaram menor suscetibilidade ao herbicida glyphosate. Não houve correspondência entre a estrutura de grupos dos acessos pela análise multivariada de agrupamento com a técnica RAPD e a suscetibilidade da alface-d'água ao glyphosate.Water lettuce (Pistia stratiotes is one the most important macrophytes, classified as weed and causing serious problems in watercourses in Brazil. The aim of this research was to evaluate the genetic variability of water lettuce and its relationship with this plant's susceptibility to glyphosate. Plant samples were collected in 12 water bodies in different regions in Brazil (Americana-AMC, Cambaratiba-CBT, Curitiba-CRB, Itapura-ITP, Jaboticabal-JBT, Lagoa Santa-LST, Piraí-PRI, Rio Grande-RGD, Rubinéia-RBN, Salto Grande-SGD, Santa Gertrudes-SGT and Três Lagoas-TLG. The accesses were characterized by the use of RAPD markers (Random Amplified Polymorphic DNA, whose unspecific starters allowed the analysis of polymorphic loci, which evidenced the distribution of the accesses into two groups, with high genetic similarity inside the sub-groups, but with high genetic divergence between them. The use of the RAPD technique evidenced the existence of genetic differences between the accesses. Plants growing in plastic pots (5 L were sprayed with glyphosate at the concentrations of 0.0, 0.6, 1.2, 1.8, 2.4 kg ha-1. Herbicide effects were evaluated on the 7th, 14th, and 21st days after application (DAA with control note attributions (0% without control and 100% leading to the complete death of the plants. No correspondence was observed between the structure of the access groups by the grouping multi-varied analysis using the RAPD technique and water lettuce susceptibility to glyphosate.

  18. Variabilidade genética e sensibilidade de acessos de Pistia stratiotes ao herbicida glyphosate / Genetic variability and sensitivity of Pistia stratiotes accesses to glyphosate

    Scientific Electronic Library Online (English)

    E.A.S., Cícero; R.A., Pitelli; J.A.D., Sena; A.S., Ferraudo.

    2007-09-01

    Full Text Available A alface-d'água (Pistia stratiotes) é uma das principais entre as macrófitas aquáticas que causam problemas em corpos hídricos no Brasil e são consideradas como plantas daninhas. O presente trabalho foi realizado com os objetivos de conhecer melhor a variabilidade genética dessa macrófita e relacion [...] ar essa variabilidade com a resposta à aplicação do herbicida glyphosate. Para isso, foram coletados indivíduos em 12 corpos hídricos em diferentes cidades do território nacional (Americana, Cambaratiba, Curitiba, Itapura, Jaboticabal, Lagoa Santa, Piraí, Rio Grande, Rubinéia, Salto Grande, Santa Gertrudes e Três Lagoas). Os acessos foram caracterizados pelo uso de marcadores RAPD (DNA Polimórfico Amplificado ao Acaso), que permitiram, com o auxílio de iniciadores aleatórios, a caracterização dos locos polimórficos identificados por uma matriz de ausência e presença de bandas. Utilizando essa matriz, a análise de agrupamento permitiu nítida classificação dos acessos em três grupos com diferenças genéticas entre eles. Um ensaio de controle químico, com plantas mantidas em vasos plásticos (5 L) e pulverizadas com o herbicida glyphosate nas concentrações de 0,0, 0,6, 1,2, 1,8 e 2,4 kg ha-1, identificou, utilizando avaliações aos 7, 14 e 21 dias após aplicação, que as duas maiores doses promoveram melhor efeito herbicida. Foi verificado também que os acessos de Curitiba e Cambaratiba apresentaram menor suscetibilidade ao herbicida glyphosate. Não houve correspondência entre a estrutura de grupos dos acessos pela análise multivariada de agrupamento com a técnica RAPD e a suscetibilidade da alface-d'água ao glyphosate. Abstract in english Water lettuce (Pistia stratiotes) is one the most important macrophytes, classified as weed and causing serious problems in watercourses in Brazil. The aim of this research was to evaluate the genetic variability of water lettuce and its relationship with this plant's susceptibility to glyphosate. P [...] lant samples were collected in 12 water bodies in different regions in Brazil (Americana-AMC, Cambaratiba-CBT, Curitiba-CRB, Itapura-ITP, Jaboticabal-JBT, Lagoa Santa-LST, Piraí-PRI, Rio Grande-RGD, Rubinéia-RBN, Salto Grande-SGD, Santa Gertrudes-SGT and Três Lagoas-TLG). The accesses were characterized by the use of RAPD markers (Random Amplified Polymorphic DNA), whose unspecific starters allowed the analysis of polymorphic loci, which evidenced the distribution of the accesses into two groups, with high genetic similarity inside the sub-groups, but with high genetic divergence between them. The use of the RAPD technique evidenced the existence of genetic differences between the accesses. Plants growing in plastic pots (5 L) were sprayed with glyphosate at the concentrations of 0.0, 0.6, 1.2, 1.8, 2.4 kg ha-1. Herbicide effects were evaluated on the 7th, 14th, and 21st days after application (DAA) with control note attributions (0% without control and 100% leading to the complete death of the plants). No correspondence was observed between the structure of the access groups by the grouping multi-varied analysis using the RAPD technique and water lettuce susceptibility to glyphosate.

  19. Fluorescence enhancement of CdTe/CdS quantum dots by coupling of glyphosate and its application for sensitive detection of copper ion

    International Nuclear Information System (INIS)

    Graphical abstract: Glyphosate (Glyp) had been used to modify the surface of CdTe/CdS QDs, resulting in the enhancement of fluorescence intensity. The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu2+ based on the fluorescence quenching. Highlights: ? Water soluble CdTe/CdS quantum dots capped with glyphosate were firstly synthesized. ? The fluorescence of the Glyp-functionalized QDs was quenched by copper ion. ? A new fluorescent sensor for copper ion was developed based on the prepared QDs. ? The sensor exhibited high sensitivity and good selectivity for copper ion. - Abstract: A novel fluorescent probe for Cu2+ determination based on the fluorescence quenching of glyphosate (Glyp)-functionalized quantum dots (QDs) was firstly reported. Glyp had been used to modify the surface of QDs to form Glyp-functionalized QDs following the capping of thioglycolic acid on the core–shell CdTe/CdS QDs. Under the optimal conditions, the response was linearly proportional to the concentration of Cu2+ between 2.4 × 10?2 ?g mL?1 and 28 ?g mL?1, with a detection limit of 1.3 × 10?3 ?g mL?1 (3?). The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu2+. The fluorescent probe was successfully used for the determination of Cu2+ in environmental samples. The mechanism of reaction was also discussed.

  20. Using vegetative index and modified derivative for early detection of soybean plant injury from glyphosate

    Science.gov (United States)

    Glyphosate is a non-selective, systemic herbicide highly toxic to sensitive plant species, and its use has seen a significant increase due to the increased adoption of genetically modified glyphosate-resistant crops since the mid-1990s. Glyphosate application for weed control in glyphosate-resistant...

  1. Fluorescence enhancement of CdTe/CdS quantum dots by coupling of glyphosate and its application for sensitive detection of copper ion

    Energy Technology Data Exchange (ETDEWEB)

    Liu Zhengqing; Liu Shaopu; Yin Pengfei [Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); He Youqiu, E-mail: heyq@swu.edu.cn [Key Laboratory on Luminescence and Real-Time Analysis, Ministry of Education, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China)

    2012-10-01

    Graphical abstract: Glyphosate (Glyp) had been used to modify the surface of CdTe/CdS QDs, resulting in the enhancement of fluorescence intensity. The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu{sup 2+} based on the fluorescence quenching. Highlights: Black-Right-Pointing-Pointer Water soluble CdTe/CdS quantum dots capped with glyphosate were firstly synthesized. Black-Right-Pointing-Pointer The fluorescence of the Glyp-functionalized QDs was quenched by copper ion. Black-Right-Pointing-Pointer A new fluorescent sensor for copper ion was developed based on the prepared QDs. Black-Right-Pointing-Pointer The sensor exhibited high sensitivity and good selectivity for copper ion. - Abstract: A novel fluorescent probe for Cu{sup 2+} determination based on the fluorescence quenching of glyphosate (Glyp)-functionalized quantum dots (QDs) was firstly reported. Glyp had been used to modify the surface of QDs to form Glyp-functionalized QDs following the capping of thioglycolic acid on the core-shell CdTe/CdS QDs. Under the optimal conditions, the response was linearly proportional to the concentration of Cu{sup 2+} between 2.4 Multiplication-Sign 10{sup -2} {mu}g mL{sup -1} and 28 {mu}g mL{sup -1}, with a detection limit of 1.3 Multiplication-Sign 10{sup -3} {mu}g mL{sup -1} (3{delta}). The Glyp-functionalized QDs fluorescent probe offers good sensitivity and selectivity for detecting Cu{sup 2+}. The fluorescent probe was successfully used for the determination of Cu{sup 2+} in environmental samples. The mechanism of reaction was also discussed.

  2. Cover Crops Reduce Water, Sediment, and Herbicide Loss in Acreage Requiring Tillage to Control Glyphosate-Resistant Weeds

    Science.gov (United States)

    Glyphosate-resistant crops (GRCs) facilitated the adoption of no-tillage cropping systems. No-tillage, that is, omitting all tilling, disking, or harrowing operations, promotes crop residue accumulation on the soil surface. Crop residues protect the soil surface from rainfall impact, impede surfac...

  3. REDUCED TRANSLOCATION IS THE CAUSE OF ANTAGONISM OF GLYPHOSATE BY MSMA IN BROWNTOP MILLET (BRACHIARIA RAMOSE) AND PALMER AMARANTH (AMARANTHUS PALMER)

    Science.gov (United States)

    Studies were conducted in growth chambers to characterize absorption and translocation of 14C-glyphosate applied alone or in mixture with MSMA in browntop millet and Palmer amaranth. MSMA antagonized activity of glyphosate in both weed species. Absorption of 14C-glyphosate in Palmer amaranth was r...

  4. Glyphosate Accumulation and Detrimental Effects on Coffea Arabica : Chemical Analysis and Biological Effect Measurements

    DEFF Research Database (Denmark)

    Schrübbers, Lars Christoph

    2015-01-01

    Coffee is one of the most popular beverages worldwide and a highly traded commodity. In order to maintain a high yield of the perennial crop, weed competition for resources needs to be reduced. For this purpose herbicides are commonly applied, with glyphosate being one of the most prominent herbicides in coffee fields. Glyphosate [N-(phosphonomethyl)glycine], the active ingredient in Roundup®, is characterized as systemic, non-selective, with a broad weed spectrum, inhibiting the enzyme 5-enolpyruvyl shikimate 3-phosphate synthase (EPSPS). The inhibition leads to an accumulation of shikimic acid. In coffee plantations glyphosate symptoms are commonly observed, probably caused by an unintentional spray drift. Root uptake represents an additional uptake route. Glyphosate can be applied several times per year thus a potential accumulation within the plant would lead to higher tissue concentrations than from single applications. The aim of this PhD thesis was to investigate the interaction of glyphosate with the coffee plant. An optimized coffee production, by minimizing the risk for a potential yield loss, is important due to the high commercial value of the crop. However, only limited data is available on the interaction of glyphosate with coffee trees and perennial crops in general; especially with respect to extended time periods after the exposure and multiple applications within the commercial life span of the individual plant. In order to determine glyphosate and aminomethylphosphonic acid (AMPA), the main glyphosate metabolite, in leaf material a method using liquid chromatography coupled to mass spectrometry (LC-MS) was developed. Variations of the method were tested using a full or simplified sample clean-up procedure with single quadrupole MS detection. Additionally the simplified sample treatment was further developed by the use of ultra performance liquid chromatography (UPLC) coupled to a triple quadrupole MS/MS system. All tested variations showed sufficient accuracy (recovery: 80-120%) and precision (? 20 relative standard deviation in percentage, RSD%). The full method and the MS/MS system provided a limit of quantification (LOQ) below 0.1 mg/kg; the commonly used maximum residue limit (MRL) for glyphosate in plant derived food products. Glyphosate was found in all samples analyzed from different coffee fields, regardless of management practices. AMPA was not detected above the LOQ in any greenhouse or field sample analyzed. Glyphosate levels seemed to increase in leaf material with multiple applications, indicating the risk for an accumulation in the coffee tree. In an experimental field trial glyphosate was, however, not detected after several applications. The biological response of young coffee plants to single glyphosate applications was evaluated using doseresponse curves (DRC) and shikimic acid levels. Furthermore the effect of multiple exposures on the viii severity of plant damage was investigated. The DRC revealed the presence of glyphosate symptoms to be the most sensitive response variable evaluated. Consequently, when symptoms are absent the risk for plant damage and yield loss is low. The field rate used in the greenhouse study, causing symptoms in 50% of the plants was realistic for field exposure scenarios. When symptoms are present, presumably caused by glyphosate, shikimic acid accumulation can be used for confirmation purposes. The best sampling time was 1 to 2 weeks after treatment, using only the youngest leaves of the plant. Shikimic acid levels were correlated with glyphosate levels 14 to 28 days after treatment (DAT). Earlier and later sampling did not show this correlation within the greenhouse study. A negative effect of glyphosate on the yield, correlated to plant leaf coverage was observed. The yield reduction was only observed for the first application carried out and not distinctively related to the number of applications or field rate. Most likely because of the plant age, possible other reasons are discussed. Biological response variables were not significantly increased by

  5. Efecto del glifosato sobre el crecimiento y acumulación de azúcares libres en dos biotipos de lolium perenne de distinta sensibilidad al herbicida / Glyphosate effects on the growth and free sugar accumulation of two lolium perenn e biotypes with different herbicide sensitivity

    Scientific Electronic Library Online (English)

    M., Yanniccari; C., Istilart; D.O., Giménez; H., Acciaresi; A.M, Castro.

    2012-03-01

    Full Text Available El movimiento sistémico del glifosato está determinado por el transporte de fotoasimilados. A su vez, la capacidad de un destino de consumir los asimilados está condicionada por su actividad metabólica. Pese a su importancia, la relación entre el glifosato y la síntesis de azúcares en hojas fuente h [...] a sido poco abordada. El objetivo del presente trabajo fue evaluar los efectos del glifosato sobre el crecimiento y la acumulación de azúcares libres en dos biotipos de Lolium perenne de baja y alta sensibilidad al herbicida. Se trabajó con clones de ambos tipos de plantas, en macollaje, tratados con 1.440 g e.a. ha-1 de glifosato y sin tratamiento herbicida como controles. Se evaluó periódicamente el efecto del glifosato sobre el rebrote de hojas hasta las 50 horas post-aplicación y sobre los niveles de azúcares libres totales, reductores y no reductores en hojas a 1, 2, 3 y 5 días post-aplicación. A partir de las 25 horas post-aplicación, el glifosato provocó una disminución del crecimiento del 58% en el biotipo susceptible, con una acumulación de azúcares libres superior al 90% con relación al control, desde el primer día post-aplicación en adelante. La inhibición del crecimiento, inducida por el glifosato en plantas susceptibles, no depende de la limitación del traslado de fotoasimilados desde la parte aérea. Por tanto, la acumulación de azúcares libres en hojas podría explicarse por la caída en la tasa de crecimiento. En el biotipo de baja sensibilidad, en el que no se detectó inhibición del crecimiento, estos efectos fueron limitados. Abstract in english The systemic movement of glyphosate is determined by the transport of photoassimilates. In turn, the capacity of a destination to consume assimilates is conditioned by their metabolic activity. Despite its importance, the relationship between the glyphosate and the sugar synthesis from source leaves [...] has been little studied. The aim of this work was to determine the effect of glyphosate on the growth and free sugar accumulation of two Lolium perenne biotypes of low and high glyphosate sensitivity. It was worked with clones of both types, in tillering, sprayed with 1,440 g a.e. ha-1 of glyphosate as treatments and without herbicide as controls. The glyphosate effects on the regrowth of leaves was studied until 50 hours post-application and on total free sugar, reducing free sugar and nonreducing free sugar from leaves to 1, 2, 3 and 5 days post-application were periodically evaluated. From 25 hours after glyphosate application, it caused on the susceptible biotype a growth decrease of 58% and an accumulation of free sugar above 90% compared to controls. In susceptible biotypes, growth inhibition does not depend on a reduced photoassimilate translocation from the overground part. Therefore, the free sugar accumulation in leaves could be explained by the fall in the rate of growth. These effects are limited in the low sensitivity biotype, where growth inhibition has not been detected.

  6. Assessing crop injury caused by aerially applied glyphosate drift using spray sampling

    Science.gov (United States)

    Crop injury caused by off-target drift of aerially applied glyphosate is of great concern to farmers and aerial applicators. An experiment was conducted in 2009 to determine the extent of injury due to near-field glyphosate drift from aerial application to glyphosate-sensitive cotton, corn and soybe...

  7. Decisions reduce sensitivity to subsequent information.

    Science.gov (United States)

    Bronfman, Zohar Z; Brezis, Noam; Moran, Rani; Tsetsos, Konstantinos; Donner, Tobias; Usher, Marius

    2015-07-01

    Behavioural studies over half a century indicate that making categorical choices alters beliefs about the state of the world. People seem biased to confirm previous choices, and to suppress contradicting information. These choice-dependent biases imply a fundamental bound of human rationality. However, it remains unclear whether these effects extend to lower level decisions, and only little is known about the computational mechanisms underlying them. Building on the framework of sequential-sampling models of decision-making, we developed novel psychophysical protocols that enable us to dissect quantitatively how choices affect the way decision-makers accumulate additional noisy evidence. We find robust choice-induced biases in the accumulation of abstract numerical (experiment 1) and low-level perceptual (experiment 2) evidence. These biases deteriorate estimations of the mean value of the numerical sequence (experiment 1) and reduce the likelihood to revise decisions (experiment 2). Computational modelling reveals that choices trigger a reduction of sensitivity to subsequent evidence via multiplicative gain modulation, rather than shifting the decision variable towards the chosen alternative in an additive fashion. Our results thus show that categorical choices alter the evidence accumulation mechanism itself, rather than just its outcome, rendering the decision-maker less sensitive to new information. PMID:26108628

  8. 76 FR 19701 - Glyphosate (N-

    Science.gov (United States)

    2011-04-08

    ...found in rats or mice. In a chronic toxicity study in dogs, no systemic effects were found. Acceptable...N-acetyl glyphosate. N- acetyl glyphosate is found in genetically modified (GMO) glyphosate- resistant commodities,...

  9. Effects of Glyphosate Application on Seed Iron and Root Ferric (III) Reductase in Soybean Cultivars

    Science.gov (United States)

    Previous research demonstrated that nitrate assimilation and nitrogen fixation were significantly reduced by glyphosate (Gly) drift in glyphosate-susceptible (GS) soybean, but soybean had the ability to recover from the physiological stress caused by glyphosate drift. The objective of this study was...

  10. Glyphosate-resistant palmer amaranth: a threat to conservation agriculture

    Science.gov (United States)

    Conservation tillage reduces the physical movement of soil to the minimum required for crop establishment and production. Adoption of conservation tillage increased dramatically with the advent of transgenic, glyphosate-resistant crops that permitted in-season, over-the-top use of glyphosate, a broa...

  11. Efeitos de diferentes formulações comerciais de glyphosate sobre estirpes de Bradyrhizobium / Effects of different glyphosate commercial formulations on Bradyrhizobium strains

    Scientific Electronic Library Online (English)

    J.B., Santos; R.J.S., Jacques; S.O., Procópio; M.C.M., Kasuya; A.A., Silva; E.A., Santos.

    2004-06-01

    Full Text Available O objetivo deste trabalho foi avaliar efeitos de formulações comerciais de glyphosate sobre estirpes de Bradyrhizobium, em condições de laboratório. As formulações foram aplicadas na concentração de 43,2 µg L-1 do equivalente ácido. As bactérias foram inoculadas em meio de cultura à base de manitol [...] e extrato de levedura (YM). O efeito do herbicida no crescimento das estirpes de Bradyrhizobium foi avaliado mediante leitura da densidade ótica em espectrofotômetro. Avaliou-se o crescimento das estirpes de B. japonicum SEMIA 5079 e de B. elkanii SEMIA 5019 e SEMIA 587 sob efeito de nove formulações de glyphosate: Zapp Qi®, Roundup®, Roundup Multiação®, Roundup Transorb®, Roundup WG®, Trop®, Agrisato®, glyphosate técnico [padrão de N-(phosphonomethyl) glycina] e controle sem adição de herbicida (testemunha para as estirpes). Foram utilizadas seis repetições. Confeccionaram-se curvas de crescimento para cada estirpe. Pelos resultados, pôde-se observar que todas as formulações de glyphosate causaram efeitos diferenciados sobre as estirpes de Bradyrhizobium SEMIA 5019, SEMIA 5079 e SEMIA 587. Constatou-se que a formulação Zapp Qi foi a menos tóxica às estirpes de Bradyrhizobium avaliadas. A maior toxicidade foi observada para Roundup Transorb, que provocou reduções no crescimento acima de 94% para todas as estirpes de Bradyrhizobium estudadas. Não se observou correlação entre o tipo de sal - isopropilamina, amônio ou potássico, presentes na formulação herbicida - e o grau de inibição no crescimento das estirpes. SEMIA 587 foi a estirpe menos tolerante à maioria das formulações testadas, porém SEMIA 5019 foi a mais sensível ao glyphosate padrão, sem adição de sais ou de outros aditivos. Abstract in english This work aimed to evaluate the effects of glyphosate commercial formulations on Bradyrhizobium strains under laboratory conditions. The formulations were applied in the concentration of 43.2 µg L-1 of the a.e. and the strains were inoculated in yeast extract manitol (YM). Herbicide effect on the gr [...] owth of the Bradyrhizobium strains was assessed by optic density reading in a spectrophotometer. Twenty seven treatments arranged in a factorial design were evaluated and consisted of one strain of B. japonicum: SEMIA 5079; and two strains of B. elkanii: SEMIA 5019 and SEMIA 587, under the effect of nine glyphosate formulations: Zapp QI®, Roundup®, Roundup Multiação®, Roundup Transorb®, Roundup WG®, Trop®, Agrisato®, technical glyphosate [N-(phosphonomethyl) glycine] and control without herbicide addition (as the strain control treatment), with six replications. A growth curve was established for each strain. It could be observed that the different glyphosate formulations Zapp Qi, Roundup, Roundup Multiação, Roundup transorb, Roundup WG, Trop and Agrisato caused differentiated effects on the strains of Bradyrhizobium SEMIA 5019, SEMIA 5079 and SEMIA 587. It was verified that the Zapp Qi formulation was the least toxic to the strains. The highest toxicity was observed for Roundup Transorb, which reduced growth over 94% for all the strains assessed. Correlation was not observed among the type of salt, isopropylamine, ammonium or potassic, present in the formulation herbicides, and the toxicity degree to the strains. The strain SEMIA 587 was the least tolerant to most formulations while SEMIA 5019 was the most sensitive to the control treatment N- (phosphonomethyl) glycine, without salts or other additives.

  12. Efeitos de diferentes formulações comerciais de glyphosate sobre estirpes de Bradyrhizobium Effects of different glyphosate commercial formulations on Bradyrhizobium strains

    Directory of Open Access Journals (Sweden)

    J.B. Santos

    2004-06-01

    Full Text Available O objetivo deste trabalho foi avaliar efeitos de formulações comerciais de glyphosate sobre estirpes de Bradyrhizobium, em condições de laboratório. As formulações foram aplicadas na concentração de 43,2 µg L-1 do equivalente ácido. As bactérias foram inoculadas em meio de cultura à base de manitol e extrato de levedura (YM. O efeito do herbicida no crescimento das estirpes de Bradyrhizobium foi avaliado mediante leitura da densidade ótica em espectrofotômetro. Avaliou-se o crescimento das estirpes de B. japonicum SEMIA 5079 e de B. elkanii SEMIA 5019 e SEMIA 587 sob efeito de nove formulações de glyphosate: Zapp Qi®, Roundup®, Roundup Multiação®, Roundup Transorb®, Roundup WG®, Trop®, Agrisato®, glyphosate técnico [padrão de N-(phosphonomethyl glycina] e controle sem adição de herbicida (testemunha para as estirpes. Foram utilizadas seis repetições. Confeccionaram-se curvas de crescimento para cada estirpe. Pelos resultados, pôde-se observar que todas as formulações de glyphosate causaram efeitos diferenciados sobre as estirpes de Bradyrhizobium SEMIA 5019, SEMIA 5079 e SEMIA 587. Constatou-se que a formulação Zapp Qi foi a menos tóxica às estirpes de Bradyrhizobium avaliadas. A maior toxicidade foi observada para Roundup Transorb, que provocou reduções no crescimento acima de 94% para todas as estirpes de Bradyrhizobium estudadas. Não se observou correlação entre o tipo de sal - isopropilamina, amônio ou potássico, presentes na formulação herbicida - e o grau de inibição no crescimento das estirpes. SEMIA 587 foi a estirpe menos tolerante à maioria das formulações testadas, porém SEMIA 5019 foi a mais sensível ao glyphosate padrão, sem adição de sais ou de outros aditivos.This work aimed to evaluate the effects of glyphosate commercial formulations on Bradyrhizobium strains under laboratory conditions. The formulations were applied in the concentration of 43.2 µg L-1 of the a.e. and the strains were inoculated in yeast extract manitol (YM. Herbicide effect on the growth of the Bradyrhizobium strains was assessed by optic density reading in a spectrophotometer. Twenty seven treatments arranged in a factorial design were evaluated and consisted of one strain of B. japonicum: SEMIA 5079; and two strains of B. elkanii: SEMIA 5019 and SEMIA 587, under the effect of nine glyphosate formulations: Zapp QI®, Roundup®, Roundup Multiação®, Roundup Transorb®, Roundup WG®, Trop®, Agrisato®, technical glyphosate [N-(phosphonomethyl glycine] and control without herbicide addition (as the strain control treatment, with six replications. A growth curve was established for each strain. It could be observed that the different glyphosate formulations Zapp Qi, Roundup, Roundup Multiação, Roundup transorb, Roundup WG, Trop and Agrisato caused differentiated effects on the strains of Bradyrhizobium SEMIA 5019, SEMIA 5079 and SEMIA 587. It was verified that the Zapp Qi formulation was the least toxic to the strains. The highest toxicity was observed for Roundup Transorb, which reduced growth over 94% for all the strains assessed. Correlation was not observed among the type of salt, isopropylamine, ammonium or potassic, present in the formulation herbicides, and the toxicity degree to the strains. The strain SEMIA 587 was the least tolerant to most formulations while SEMIA 5019 was the most sensitive to the control treatment N- (phosphonomethyl glycine, without salts or other additives.

  13. Reduced taste sensitivity in congenital blindness

    DEFF Research Database (Denmark)

    Gagnon, Lea; Kupers, Ron; Ptito, Maurice

    2013-01-01

    Sight is undoubtedly not only important for food identification and selection but also for the modulation of gustatory sensitivity. We can, therefore, assume that taste sensitivity and eating habits are affected by visual deprivation from birth. We measured taste detection and identification thresholds of the 5 basic tastants in 13 congenitally blind and 13 sighted control subjects. Participants also answered several eating habits questionnaires, including the Food Neophobia Scale, the Food Vari...

  14. Glyphosate in northern ecosystems.

    Science.gov (United States)

    Helander, Marjo; Saloniemi, Irma; Saikkonen, Kari

    2012-10-01

    Glyphosate is the main nonselective, systemic herbicide used against a wide range of weeds. Its worldwide use has expanded because of extensive use of certain agricultural practices such as no-till cropping, and widespread application of glyphosate-resistant genetically modified crops. Glyphosate has a reputation of being nontoxic to animals and rapidly inactivated in soils. However, recent evidence has cast doubts on its safety. Glyphosate may be retained and transported in soils, and there may be cascading effects on nontarget organisms. These processes may be especially detrimental in northern ecosystems because they are characterized by long biologically inactive winters and short growing seasons. In this opinion article, we discuss the potential ecological, environmental and agricultural risks of intensive glyphosate use in boreal regions. PMID:22677798

  15. Reduced taste sensitivity in congenital blindness

    DEFF Research Database (Denmark)

    Gagnon, Lea; Kupers, Ron

    2013-01-01

    Sight is undoubtedly not only important for food identification and selection but also for the modulation of gustatory sensitivity. We can, therefore, assume that taste sensitivity and eating habits are affected by visual deprivation from birth. We measured taste detection and identification thresholds of the 5 basic tastants in 13 congenitally blind and 13 sighted control subjects. Participants also answered several eating habits questionnaires, including the Food Neophobia Scale, the Food Variety Seeking Tendency Scale, the Intuitive Eating Scale, and the Body Awareness Questionnaire. Our behavioral results showed that compared with the normal sighted, blind subjects have increased thresholds for taste detection and taste identification. This finding is at odds with the superior performance of congenitally blind subjects in several tactile, auditory and olfactory tasks. Our psychometric data further indicate that blind subjects more strongly rely on internal hunger and satiety cues, instead of external contextual or emotional cues, to decide when and what to eat. We suggest that the lower taste sensitivity observed in congenitally blind individuals is due to various blindness-related obstacles when shopping for food, cooking and eating out, all of which contribute to underexpose the gustatory system to a larger variety of taste stimuli.

  16. Glyphosate-Resistant Goosegrass from Mississippi

    Directory of Open Access Journals (Sweden)

    Vijay K. Nandula

    2013-05-01

    Full Text Available A suspected glyphosate-resistant goosegrass [Eleusine indica (L. Gaertn.] population, found in Washington County, Mississippi, was studied to determine the level of resistance and whether the resistance was due to a point mutation, as was previously identified in a Malaysian population. Whole plant dose response assays indicated a two- to four-fold increase in resistance to glyphosate. Leaf disc bioassays based on a glyphosate-dependent increase in shikimate levels indicated a five- to eight-fold increase in resistance. Sequence comparisons of messenger RNA for epsps, the gene encoding the enzyme 5-enolpyruvylshikimate-3-phosphate synthase, from resistant and sensitive goosegrass, revealed a cytosine to thymine nucleotide change at position 319 in the resistant accessions. This single nucleotide polymorphism causes a proline to serine amino acid substitution at position 106 in 5-enolpyruvylshikimate-3-phosphate synthase. A real-time polymerase chain reaction assay using DNA probes specific for the nucleotide change at position 319 was developed to detect this polymorphism. Goosegrass from 42 locations were screened, and the results indicated that glyphosate-resistant goosegrass remained localized to where it was discovered. Pendimethalin, s-metolachlor, clethodim, paraquat and fluazifop controlled resistant goosegrass 93% to 100%, indicating that several control options for glyphosate-resistant goosegrass are available.

  17. Effects of additives on glyphosate activity in purple nutsedge

    International Nuclear Information System (INIS)

    Effects of additives on 14 C-glyphosate penetration into purple nutsedge leaves were examined in the laboratory and efficacy of glyphosate for purple nutsedge control was studied in the greenhouse and field. The addition of (NH4)2 SO4 at 1.0% (v/v) + diesel oil at 1,0% (v/v) + Tendal at 1.0% (v/v) increased 14C-glyphosate penetration into nutsedge leaves more than the addition of either one alone. (NH4)2SO4 at 1.0% + diesel oil at 1.0% + Tendal at 0.12 or 0.25% increased the phytotoxicity of glyphosate at 0.5 and 0.75 kg, a.e./ha on nutsedge plants in the greenhouse but not in the field. Additives did not enhance glyphosate activity by reducing the number of nutsedae tubers. (author)

  18. Effect of glyphosate on carrot and tobacco cells.

    Science.gov (United States)

    Haderlie, L C; Widholm, J M; Slife, F W

    1977-07-01

    The growth of suspension-cultured carrot (Daucus carota L.) and tobacco (Nicotiana tabacum L. cv. Xanthi) cells was inhibited by glyphosate (N-[phosphonomethyl]glycine). This inhibition was reversed by adding combinations of phenylalanine, tyrosine, and tryptophan or casein hydrolysate. Casein hydrolysate and phenylalanine + tyrosine + tryptophan were the most effective treatments. Reversal of glyphosate-induced inhibition occurred only if the aromatic amino acids were added during the first 8 days of glyphosate incubation. Glyphosate uptake was not reduced when the aromatic amino acids or casein hydrolysate were added.Even though phenylalanine biosynthesis is a suggested site for glyphosate action, inhibitory levels of glyphosate did not lower free phenylalanine concentrations in carrot cells within 10 days. (14)C-Phenylalanine studies indicated that the metabolic pool size was, likewise, not decreased.In carrot cells total free amino acids increased within 6 hours after glyphosate addition. Cell protein levels declined within 48 hours following glyphosate treatment.Studies on (14)C-thymidine and (14)C-uridine incorporation were complicated by rapid metabolism of these compounds to (14)CO(2). PMID:16660038

  19. Estádio de desenvolvimento e superfície foliar reduzem a eficiência de chlorimuron-ethyl e glyphosate em Conyza sumatrensis / Developmental stage and leaf surface reduce the efficiency of chlorimuron-ethyl and glyphosate in Conyza sumatrensis

    Scientific Electronic Library Online (English)

    F.M., Santos; L., Vargas; P.J., Christoffoleti; D., Agostinetto; T.N., Martin; Q., Ruchel; J.A., Fernando.

    2014-06-01

    Full Text Available Nos Estados do Rio Grande do Sul e do Paraná, há frequentes relatos de falhas de controle de Conyza sumatrensis com chlorimuron-ethyl em lavouras de soja. Assim, os objetivos deste trabalho foram caracterizar morfologicamente as folhas de Conyza sumatrensis e avaliar o controle com herbicidas aplica [...] dos em biótipos dessa planta daninha em três estádios de desenvolvimento. Foram realizados dois estudos, com experimentos em casa de vegetação, em delineamento inteiramente casualizado com quatro repetições. No primeiro estudo, os biótipos de buva foram coletados e identificados; já no segundo estudo avaliou-se a resposta de biótipos aos herbicidas, doses e estádios de desenvolvimento. As doses de herbicidas foram: 0,0; 6,25; 12,5; 25; 50; 100; 200; e 400, representadas em porcentagem da dose de registro dos herbicidas chlorimuron-ethyl (20 g ha-1) e glyphosate (720 g e.a. ha-1), aplicadas de modo isolado ou associadas em três estádios de desenvolvimento dos quatro biótipos (2, 5, 17 e 20) de Conyza sumatrensis (altura de 0,5-1 cm e 3-4 folhas; altura 1-2 cm e 6-7 folhas; e altura de 10-12 cm e 12-14 folhas). As variáveis analisadas foram controle, fitomassa seca da parte aérea e as densidades tricomática e estomática da superfície foliar dos biótipos em diferentes estádios de desenvolvimento. Os resultados demonstram que os estádios de desenvolvimento alteram a eficácia dos herbicidas, e aplicações em estádios avançados de desenvolvimento diminuem a eficácia de controle. A exceção foi o biótipo 5 de Conyza sumatrensis, que demonstrou resistência ao glyphosate, independentemente do estádio de desenvolvimento no momento da aplicação do herbicida. Houve variação no número de tricomas entre os biótipos em todos os estádios de desenvolvimento, e o número de estômatos diminuiu com o desenvolvimento dos biótipos. Abstract in english In the states of Rio Grande do Sul and Paraná, there are frequent reports of failure to control Conyza sumatrensis with chlorimuron-ethyl in soybean crops. Thus, the objectives of this study were to characterize Conyza sumatrensis leaves morphologically and evaluate herbicide control in biotypes of [...] this weed at three stages. Two studies were conducted, with experiments in a greenhouse in a completely randomized design with four replications. In the first study, horseweed biotypes were collected and identified, and the second study evaluated the responses of herbicide rates and development stages. The herbicide rates were: 0.0, 6.25, 12.5, 25, 50, 100, 200 and 400, represented as a percentage of the dose registry of herbicides chlorimuron­ethyl (20 g ha-1) and glyphosate (720 g e.a. ha-1) applied in isolation or associated at three developmental stages of four Conyza sumatrensis (2, 5, 17 and 20) biotypes (height = 0.5-1 cm and 3-4 leaves, height = 1-2 cm and 6-7 leaves, height = 10-12 cm, 12-14 leaves). The variables analyzed were control, shoot dry weight and trichome and stomatal densities biotypes of the leaf surface at different stages of development. The results obtained demonstrate that the developmental stages affect the effectiveness of the herbicides, and applications at advanced stages of development decrease the effectiveness of control. The exception was biotype 5 of Conyza sumatrensis, which shows resistance to glyphosate, regardless of stage of development at the time of herbicide application. There was variation in the number of trichomes among biotypes at all stages of development, and the number of stomata decreased with the development of biotypes.

  20. Reduced Baroreflex Sensitivity in Cluster Headache Patients

    DEFF Research Database (Denmark)

    Barloese, Mads C J; Mehlsen, Jesper

    2015-01-01

    OBJECTIVE AND BACKGROUND: Important elements of cluster headache (CH) pathophysiology may be seated in the posterior hypothalamus. Cranial autonomic features are inherent, but involvement of systemic autonomic control is still debated. We aimed to characterize autonomic function as investigated by baroreflex sensitivity (BRS) in CH patients. METHODS: Twenty-six active CH patients and an equal number of age-, sex-, and BMI-matched controls underwent head-up tilt table test and BRS was determined by the sequence method. RESULTS: Compared with controls, patients exhibited a blunted reactivity of RR intervals in response to falls and increases in systolic blood pressure (SBP) (15.3 vs 20.0?ms/mmHg, P?=?.0041) in the supine position. Also, compared with controls, BRS was lower in patients having suffered an attack within the past 12 hours (n?=?13, 12.5 vs 22.3?ms/mmHg, P?=?.0091), opposed to those patients who had not (n?=?13, 16.0?ms/mmHg, P?=?.1523). In the tilted position, the drop in SBP at the carotid sinuses was higher in patients who had recently suffered an attack. Despite this, they exhibited a less marked shortening of RR intervals when compared with patients who had been attack free for longer. CONCLUSIONS: CH patients exhibit a subclinical blunting of BRS that may be affected by the attacks themselves. The fast RR interval fluctuations used in this method reflects cardiovagal responses, thus the blunted responses are suggestive of dysfunction in the parasympathetic division of the autonomic nervous system or in the central relay of impulses from the baroreceptors.

  1. Hormesis with glyphosate depends on coffee growth stage

    Scientific Electronic Library Online (English)

    LEONARDO B. DE, CARVALHO; PEDRO L.C.A., ALVES; STEPHEN O., DUKE.

    2013-06-01

    Full Text Available Os sistemas de manejo de plantas daninhas em quase todos os pomares de café do Brasil permitem que o herbicida pulverizado sofra deriva sobre a cultura. Com objetivo de avaliar se há algum efeito do glyphosate, herbicida mais comumente utilizado em pomares de café, sobre as plantas de café, uma ampl [...] a faixa de doses do herbicida foi aplicada diretamente sobre plantas de café em dois distintos estádios de crescimento da planta. Embora o crescimento de ambas as plantas novas e velhas tenha sido reduzido em doses mais altas de glyphosate, baixas doses não causaram efeitos sobre características de crescimento de plantas novas e estimularam o crescimento das mais velhas. Portanto, o efeito hormético do glyphosate é dependente do estádio de crescimento da planta de café no momento da aplicação do herbicida. Abstract in english Weed management systems in almost all Brazilian coffee plantations allow herbicide spray to drift on crop plants. In order to evaluate if there is any effect of the most commonly used herbicide in coffee production, glyphosate, on coffee plants, a range of glyphosate doses were applied directly on c [...] offee plants at two distinct plant growth stages. Although growth of both young and old plants was reduced at higher glyphosate doses, low doses caused no effects on growth characteristics of young plants and stimulated growth of older plants. Therefore, hormesis with glyphosate is dependent on coffee plant growth stage at the time of herbicide application.

  2. The herbicide Glyphosate affects nitrification in the Elbe estuary, Germany

    Science.gov (United States)

    Sanders, Tina; Lassen, Stephan

    2015-04-01

    The Elbe River is one of the biggest European rivers discharging into the North Sea. It also transports high amounts of nutrients and pollutants like pesticides. Important source regions of both nutrients and pollutants are located within the river catchment, which is dominated by agricultural land-use. From these agricultural soils, pesticides can be carried via the river and estuary into the North Sea. Glyphosate (N-(phosphonomethyl) glycine) is the most commonly used herbicide worldwide and mainly used to regulate unwanted plant growth and for the expedition of crop ripening. In Germany, ~ 6000 tons of glyphosate are applied yearly in agriculture and private use. Glyphosate is degradable by microorganisms and has a half-life in water of 35 to 60 days. This herbicide specifically inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), an enzyme that catalyzes the biosynthesis of essential aromatic amino acids in plants, fungi, and bacteria. Nitrifying bacteria, which play an important role in the internal nitrogen cycling in the Elbe estuary, also possess this enzyme. The aim of our study was to quantify the concentration of glyphosate in water and sediment samples of the Elbe to get an overview about relevant environmental levels and to assess the impact of glyphosate on inhibition of nitrifying activities. To quantify the effect of glyphosate on nitrification activity, natural samples as well as pure cultures of Nitrosomonas europea (strain Nm50) were incubated with different concentrations of glyphosate over a period of some weeks. The nitrifying activity was determined according to changes of the nitrite and nitrate concentration as well as the cell number. Glyphosate was detectable in water and sediment samples in the Elbe estuary with up to 5 ppb mainly in the Port of Hamburg region. In both incubation experiments an inhibiting effect of glyphosate on nitrification could be shown. The incubated natural water sample was affected by a glyphosate concentration that was 1000 fold higher than the measured natural levels. The pure culture Nitrosomonas europaea (Nm 50) was more sensitive and was already inhibited by concentrations 10 to 100 fold above the in-situ concentrations. Overall, we find that glyphosate is apparently not as easily degradable as expected, as it can be detected in the water column and sediment of the Elbe estuary in spring and summer. Our results indicate that especially during bacterial growth, the natural nitrifying community can be affected if glyphosate concentrations in the water column increase.

  3. Root-Zone Glyphosate Exposure Adversely Affects Two Ditch Species

    OpenAIRE

    Lyndsay E. Saunders; Koontz, Melissa B.; Reza Pezeshki

    2013-01-01

    Glyphosate, one of the most applied herbicides globally, has been extensively studied for its effects on non-target organisms. In the field, following precipitation, glyphosate runs off into agricultural ditches where it infiltrates into the soil and thus may encounter the roots of vegetation. These edge-of-field ditches share many characteristics with wetlands, including the ability to reduce loads of anthropogenic chemicals through uptake, transformation, and retention. Different species wi...

  4. Use of Fe/Al drinking water treatment residuals as amendments for enhancing the retention capacity of glyphosate in agricultural soils.

    Science.gov (United States)

    Zhao, Yuanyuan; Wendling, Laura A; Wang, Changhui; Pei, Yuansheng

    2015-08-01

    Fe/Al drinking water treatment residuals (WTRs), ubiquitous and non-hazardous by-products of drinking water purification, are cost-effective adsorbents for glyphosate. Given that repeated glyphosate applications could significantly decrease glyphosate retention by soils and that the adsorbed glyphosate is potentially mobile, high sorption capacity and stability of glyphosate in agricultural soils are needed to prevent pollution of water by glyphosate. Therefore, we investigated the feasibility of reusing Fe/Al WTR as a soil amendment to enhance the retention capacity of glyphosate in two agricultural soils. The results of batch experiments showed that the Fe/Al WTR amendment significantly enhanced the glyphosate sorption capacity of both soils (pglyphosate desorbed from the non-amended soils, and the Fe/Al WTR amendment effectively decreased the proportion of glyphosate desorbed. Fractionation analyses further demonstrated that glyphosate adsorbed to non-amended soils was primarily retained in the readily labile fraction (NaHCO3-glyphosate). The WTR amendment significantly increased the relative proportion of the moderately labile fraction (HCl-glyphosate) and concomitantly reduced that of the NaHCO3-glyphosate, hence reducing the potential for the release of soil-adsorbed glyphosate into the aqueous phase. Furthermore, Fe/Al WTR amendment minimized the inhibitory effect of increasing solution pH on glyphosate sorption by soils and mitigated the effects of increasing solution ionic strength. The present results indicate that Fe/Al WTR is suitable for use as a soil amendment to prevent glyphosate pollution of aquatic ecosystems by enhancing the glyphosate retention capacity in soils. PMID:26257356

  5. Reducing risk for ventilator associated pneumonia through nursing sensitive interventions.

    Science.gov (United States)

    Micik, Svatka; Besic, Nihada; Johnson, Natalie; Han, Matilda; Hamlyn, Stephen; Ball, Hayley

    2013-10-01

    The purpose of this paper is to describe an improvement initiative designed to implement nurse sensitive interventions known to reduce patients' risk for ventilator associated pneumonia (VAP), in cardiothoracic intensive care patients. This initiative is a part of one Australian critical care unit's efforts to identify and measure compliance with key nursing interventions known to improve cardiac surgical patients' outcomes. The premise behind the initiative is that improved nursing process and surveillance systems allow emerging trends to catalyse action and motivate nurses to reduce patients' risk for infection acquisition. At five and nine months following implementation of the initiative a>70% compliance rate in 11 out of the 15 nurse sensitive interventions known to reduce patients' risks for VAP and a drop in VAP incidence from 13.4% to 7.69% from per 1000 ventilator days was accomplished. PMID:23816403

  6. Weed control and yield comparisons of glyphosate- and glufosinate-resistant corn grown in rotation

    Science.gov (United States)

    A 6-yr field study was conducted from 2004 to 2009 at Stoneville, MS to examine the effects of rotating glyphosate-resistant and glufosinate-resistant corn (Zea mays L.) under reduced tillage conditions on weed control, soil weed seedbank, and yield. The four rotation systems were glyphosate-resista...

  7. Bioassay and Characterization of Several Palmer Amaranth (Amaranthus palmeri) Biotypes with Varying Tolerances to Glyphosate

    OpenAIRE

    Robert E. Hoagland; Robin H. Jordan; Teaster, Neal D

    2013-01-01

    The wide distribution of Palmer amaranth (Amaranthus palmeri) in the southern US became a serious weed control problem prior to the extensive use of glyphosate-resistant crops. Currently glyphosate-resistant populations of Palmer amaranth occur in many areas of this geographic region creating an even more serious threat to crop production. Investigations were undertaken using four biotypes (one glyphosate-sensitive, one resistant from Georgia and two of unknown tolerance from Mississippi) of...

  8. Lanolin with reduced sensitizing potential. A preliminary note.

    Science.gov (United States)

    Clark, E W; Cronin, E; Wilkinson, D S

    1977-04-01

    The allergens of lanolin appear to lie in the content of natural free fatty alcohols rather than in the total alcohols as hitherto supposed. The detectable incidence of allergy is increased by the simultaneous presence of detergent. Amongst selected lanolin-sensitive skin patients, removal of both free fatty alcohols and detergent from lanolin reduces the incidence of detectable hypersensitivity by 96%. Methods are described for determining free fatty alcohols and detergent in lanolin, and for removing them. PMID:872577

  9. DIFFERENTIAL RESPONSE OF CLONES OF EUCALYPT TO GLYPHOSATE1 / RESPOSTA DIFERENCIAL DE CLONES DE EUCALIPTO A GLYPHOSATE

    Scientific Electronic Library Online (English)

    Leonardo Bianco de, Carvalho; Pedro Luis da Costa Aguiar, Alves; Flávia Regina da, Costa.

    2015-02-01

    Full Text Available O controle de plantas daninhas é comumente feito com roçadas na entrelinha associada a aplicações dirigidas de glyphosate na linha de plantio de culturas arbóreas, acarretando risco de deriva ou aplicação acidental do herbicida, que pode afetar a cultura de interesse. O objetivo foi avaliar a respos [...] ta dos clones C219, GG100, I144 e I224 de eucalipto (Eucalyptus grandis x E. urophylla) a doses de glyphosate de 0, 18, 36, 72, 180, 360 e 720 g de equivalente ácido por hectare. Os clones apresentaram padrões de crescimento distintos no que se refere a altura da planta, número de folhas, massa seca do caule, taxa de crescimento relativo, taxa de assimilação líquida e taxa de crescimento foliar relativo. Os clones I144 e GG100 foram mais suscetíveis ao glyphosate, sendo as doses necessárias para reduzir a massa seca em 50% de 113,4 e 119,6 g ea ha-1, respectivamente. Os clones C219 e I224 foram menos suscetíveis ao glyphosate, sendo as doses necessárias para reduzir a massa seca em 50% de 237,5 e 313,5 gae ha-1, respectivamente. Clones de eucalipto respondem diferentemente à exposição ao glyphosate, e entre I224, C219, GG100 e I144 a suscetibilidade é aumentada. Abstract in english Weed control is commonly performed by the inter-row mechanical weeding associated to intrarow glyphosate directed spraying, causing a risk for drift or accidental herbicide application, that can affect the crop of interest. The objective was to evaluate the response of clones C219, GG100, I144, and [...] I224 of eucalypt (Eucalyptus grandis x E. urophylla) to glyphosate doses of 0, 18, 36, 72, 180, 360, and 720 g of acid equivalent per hectare. The clones showed different growth patterns with regard to height, leaf number, stem dry weight, relative growth rate, net assimilation rate, and relative leaf growth rate. The clones I144 and GG100 were more susceptible to glyphosate, showing the doses required to reduce dry weight by 50% of 113.4 and 119.6 g acid equivalent per hectare, respectively. The clones C219 and I224 were less susceptible to glyphosate, showing the doses required to reduce dry weight by 50% of 237.5 and 313.5 g acid equivalent per hectare, respectively. Eucalyptus clones respond differently to glyphosate exposure, so that among I224, C219, GG100, and I144, the susceptibility to the herbicide is increasing.

  10. Uptake of Glyphosate by an Arthrobacter sp

    OpenAIRE

    Pipke, Rüdiger; Schulz, Arno; Amrhein, Nikolaus

    1987-01-01

    The uptake of glyphosate (N-[phosphonomethyl]glycine) by an Arthrobacter sp. which can utilize this herbicide as its sole source of phosphorus was investigated. Orthophosphate suppressed the expression of the uptake system for glyphosate and also competed with glyphosate for uptake. The Km for glyphosate uptake was 125 ?M, and the Ki for orthophosphate was 24 ?M. Organophosphonates as well as organophosphates inhibited glyphosate uptake, but only organophosphates and orthophosphate suppressed...

  11. Crop response to glyphosate trimesium sulphosate

    OpenAIRE

    Pavlovic, Danijela; Sava VRBNICANIN; Carl REINHARDT

    2013-01-01

    Glyphosate may cause injury to non-target plants. The first detectable symptom after glyphosate treatment is the growth inhibition, followed by noticeable yellowing (chlorosis) of the treated tissue. Five to ten days after the treatment, the chlorosis turns into necrosis and the plants begin to die. Greenhouse research was conducted in 2007 to investigate the response of glyphosate resistant (GR) soybeans PAN 520 line and non-glyphosate resistant EGRET line of soybeans to glyphosate trimesium...

  12. Selection and characterization of glyphosate tolerance in birdsfoot trefoil (Lotus corniculatus)

    International Nuclear Information System (INIS)

    If birdsfoot trefoil (Lotus corniculatus L.) was tolerant to glyphosate [N-(phosphonomethyl)glycine], Canada thistle [Cirsium arvense (L.) Scop.] and other dicot weeds could be selectively controlled in certified seed production fields. Glyphosate tolerance in birdsfoot trefoil was identified in plants from the cultivar Leo, plants regenerated from tolerant callus, and selfed progeny of plants regenerated from callus. Plants from the three sources were evaluated in field studies for tolerance to glyphosate at rates up to 1.6 kg ae/ha. Plants of Leo selected for tolerance exhibited a twofold range in the rate required to reduce shoot weight 50% (I50s from 0.6 to 1.2 kg/ha glyphosate). Plants regenerated from tolerant callus had tolerance up to 66% greater than plants regenerated from unselected callus. Transgressive segregation for glyphosate tolerance was observed in the selfed progeny of two regenerated plants that both had I50s of 0.7 kg/ha glyphosate. The selfed progeny ranged from highly tolerant (I50 of 1.5 kg/ha) to susceptible (I50 of 0.5 kg/ha). Spray retention, 14C-glyphosate absorption and translocation did not account for the differential tolerance of nine plants that were evaluated from the three sources. The specific activity of 5-enolpyruvylshikimate 3-phosphate (EPSP) synthase ranged from 1.3 to 3.5 nmol/min sm-bullet mg among the nine plants and was positively correlated with glyphosate tolerance. Leo birdsfoot trefoil was found to have significant variation in glyphosate tolerance which made it possible to initiate a recurrent selection program to select for glyphosate tolerance in birdsfoot trefoil. Two cycles of selection for glyphosate tolerance were practiced in three birdsfoot trefoil populations, Leo, Norcen, and MU-81

  13. Glyphosate e nitrgênio no controle de Brachiaria decumbens Stapf em capineiras estabelecidas Glyphosate and nitrogen in the control of Brachiaria decumbens Stapf in established elephant grass stocking piles

    Directory of Open Access Journals (Sweden)

    Joadil Gonçalves de Abreu

    2006-10-01

    Full Text Available O objetivo do experimento foi avaliar a eficiência de utilização do herbicida glyphosate associado com adubação nitrogenada no controle de Brachiaria decumbens Stapf em capineiras estabelecidas. O delineamento experimental foi em blocos casualizados, com dezessete tratamentos e três repetições. Os tratamentos foram arranjados em esquema fatorial 4 x 4 + 1, sendo quatro doses de glyphosate (0, 720, 1440 e 2160 g/ha/aplicação, quatro doses de nitrogênio (0, 75, 150 e 225 kg/ha/ano e um tratamento adicional (testemunha com capina. As aplicações do nitrogênio e glyphosate, nas respectivas doses, foram realizadas imediatamente após o corte do capim-elefante. A associação entre o herbicida glyphosate (2160 g/ha/aplicação e nitrogênio (225 kg/ha/ano foi eficiente no controle de capim-braquiária em capineiras estabelecidas. A aplicação do herbicida glyphosate (2160 g/ha/aplicação reduziu o tamanho do banco de sementes de capim-braquiária no solo em 64%.The objective of this experiment was to evaluate the efficiency of the use of the herbicide glyphosate associated with nitrogen fertilization in the control of Brachiaria decumbens Stapf in elephant grass stocking piles. The experimental design used was a randomized blocks with 17 treatments and three replications. The treatments were arranged in 4x4+1 factorial scheme, namely four doses of glyphosate (0, 720, 1440 e 2160 g/ha/application, four doses of nitrogen (0, 75, 150 e 225 kg/ha/ano and one additional treatment (control with a hoeing. The application of the nitrogen and glyphosate, in the respective doses were performed immediately after the cutting of elephant grass. The association between glyphosate (2160 g/ha/application and nitrogen (225 kg/ha/ano was efficient in the control brachiaria grass in established elephant grass stocking piles. The application of the glyphosate (2160 g/ha/application reduced the size of the bank of brachiaria grass seeds in the soil in 64%.

  14. Confidence intervals for sensitivity indices using reduced-basis metamodels

    CERN Document Server

    Janon, Alexandre; Prieur, Clémentine

    2011-01-01

    Global sensitivity analysis is often impracticable for complex and time demanding numerical models, as it requires a large number of runs. The reduced-basis approach provides a way to replace the original model by a much faster to run code. In this paper, we are interested in the information loss induced by the approximation on the estimation of sensitivity indices. We present a method to provide a robust error assessment, hence enabling significant time savings without sacrifice on precision and rigourousness. We illustrate our method with an experiment where computation time is divided by a factor of nearly 6. We also give directions on tuning some of the parameters used in our estimation algorithms.

  15. DIFFERENTIAL RESPONSE OF CLONES OF EUCALYPT TO GLYPHOSATE1

    Directory of Open Access Journals (Sweden)

    Leonardo Bianco de Carvalho

    2015-02-01

    Full Text Available Weed control is commonly performed by the inter-row mechanical weeding associated to intrarow glyphosate directed spraying, causing a risk for drift or accidental herbicide application, that can affect the crop of interest. The objective was to evaluate the response of clones C219, GG100, I144, and I224 of eucalypt (Eucalyptus grandis x E. urophylla to glyphosate doses of 0, 18, 36, 72, 180, 360, and 720 g of acid equivalent per hectare. The clones showed different growth patterns with regard to height, leaf number, stem dry weight, relative growth rate, net assimilation rate, and relative leaf growth rate. The clones I144 and GG100 were more susceptible to glyphosate, showing the doses required to reduce dry weight by 50% of 113.4 and 119.6 g acid equivalent per hectare, respectively. The clones C219 and I224 were less susceptible to glyphosate, showing the doses required to reduce dry weight by 50% of 237.5 and 313.5 g acid equivalent per hectare, respectively. Eucalyptus clones respond differently to glyphosate exposure, so that among I224, C219, GG100, and I144, the susceptibility to the herbicide is increasing.

  16. Influence of glyphosate in planktonic and biofilm growth of Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Ilana Schneider Lima

    2014-09-01

    Full Text Available This study evaluated the impact of different concentrations of glyphosate (Rondup® on planktonic and biofilm growth of P. aeruginosa. Aerobic and anaerobic cultures of P. aeruginosa ATCC®15442 inoculated in MHB + glyphosate (0.845 ppm, 1.690 ppm, 8.45 ppm, 16.90 ppm, 84.50 ppm, 169 ppm, 845 ppm, and 1690 ppm and cultured in normoxia and anoxia, following their OD560nm every hour for 24 h. Biofilms of adapted cells were formed in the presence of glyphosate (0.845 to 1690 ppm in normoxia and anoxia for 36 h. Glyphosate at concentrations higher than 84.5 ppm reduces the cell density of planktonic aerobic cultures (p 0.05, and more pronounced over 169 ppm. Anaerobic biofilms have their growth more readily favored (p < 0.05, regardless of concentration. In a concentration-dependent manner, glyphosate interferes with the growth ability of P. aeruginosa ATCC®15442.

  17. Adição simultânea de sulfato de amônio e ureia à calda de pulverização do herbicida glyphosate Simultaneous addition of ammonium sulfate and urea to glyphosate spray solution

    Directory of Open Access Journals (Sweden)

    S.J.P. Carvalho

    2010-01-01

    Full Text Available Dois experimentos foram desenvolvidos em casa de vegetação, com o objetivo de avaliar a eficácia do herbicida glyphosate sobre plantas de Digitaria insularis quando soluções de ureia (U; 5 g L-1, sulfato de amônio (SA; 15 g L-1 ou U+SA (2,5 + 7,5 g L-1 foram utilizadas como veículo de pulverização. Aos 28 dias após aplicação, de acordo com as curvas de dose-resposta (primeiro experimento, foram necessários 409 g ha-1 de glyphosate para atingir 50% de controle da planta daninha (C50 quando água sem adjuvantes foi usada como veículo de pulverização. Para obtenção dos mesmos 50% de controle, as doses de glyphosate foram reduzidas para 373, 208 e 189 g ha-1; quando o herbicida foi pulverizado utilizando solução de U, SA ou U+SA, respectivamente. A redução na dose oriunda da combinação de glyphosate e U+SA também foi observada para controles de 80% (C80. No segundo experimento, a adição de U+SA à calda elevou o controle obtido com a menor dose de glyphosate (360 g ha-1, igualando-o à aplicação da maior dose (720 g ha-1 sem adjuvantes. Esses resultados evidenciam efeito complementar de U e SA em elevar a eficácia do glyphosate para controle de D. insularis.Two trials were carried out under greenhouse conditions to evaluate the efficacy of glyphosate on Digitaria insularis plants when urea (U; 5 g L-1; ammonium sulfate (AMS; 15 g L-1 or U+AMS (2.5 + 7.5 g L-1 were used as spray solutions. At 28 days after application, according to dose-response curves (first trial, 409 g ha-1 of glyphosate application were necessary to obtain 50% of weed control (C50 when water without adjuvants was used as spray solution. To reach the same 50% of weed control, glyphosate rates were reduced to 373, 208 and 189 g ha-1, when the herbicide was sprayed using a solution of U, AMS or U+AMS, respectively. Reduction in the dose of glyphosate combined with U+AMS was also observed for controls of 80% (C80. In the second trial, the addition of U+SA to glyphosate spray solution increased the control obtained at the lowest glyphosate rate (360 g ha-1, leveling it to the highest rate application (720 g ha-1 without adjuvants. These results show the complementary action of U and AMS to increase glyphosate efficacy to control D. insularis.

  18. Adição simultânea de sulfato de amônio e ureia à calda de pulverização do herbicida glyphosate / Simultaneous addition of ammonium sulfate and urea to glyphosate spray solution

    Scientific Electronic Library Online (English)

    S.J.P., Carvalho; A.C.R., Dias; G.M., Shiomi; P.J., Christoffoleti.

    Full Text Available Dois experimentos foram desenvolvidos em casa de vegetação, com o objetivo de avaliar a eficácia do herbicida glyphosate sobre plantas de Digitaria insularis quando soluções de ureia (U; 5 g L-1), sulfato de amônio (SA; 15 g L-1) ou U+SA (2,5 + 7,5 g L-1) foram utilizadas como veículo de pulverizaçã [...] o. Aos 28 dias após aplicação, de acordo com as curvas de dose-resposta (primeiro experimento), foram necessários 409 g ha-1 de glyphosate para atingir 50% de controle da planta daninha (C50) quando água sem adjuvantes foi usada como veículo de pulverização. Para obtenção dos mesmos 50% de controle, as doses de glyphosate foram reduzidas para 373, 208 e 189 g ha-1; quando o herbicida foi pulverizado utilizando solução de U, SA ou U+SA, respectivamente. A redução na dose oriunda da combinação de glyphosate e U+SA também foi observada para controles de 80% (C80). No segundo experimento, a adição de U+SA à calda elevou o controle obtido com a menor dose de glyphosate (360 g ha-1), igualando-o à aplicação da maior dose (720 g ha-1) sem adjuvantes. Esses resultados evidenciam efeito complementar de U e SA em elevar a eficácia do glyphosate para controle de D. insularis. Abstract in english Two trials were carried out under greenhouse conditions to evaluate the efficacy of glyphosate on Digitaria insularis plants when urea (U; 5 g L-1); ammonium sulfate (AMS; 15 g L-1) or U+AMS (2.5 + 7.5 g L-1) were used as spray solutions. At 28 days after application, according to dose-response curv [...] es (first trial), 409 g ha-1 of glyphosate application were necessary to obtain 50% of weed control (C50) when water without adjuvants was used as spray solution. To reach the same 50% of weed control, glyphosate rates were reduced to 373, 208 and 189 g ha-1, when the herbicide was sprayed using a solution of U, AMS or U+AMS, respectively. Reduction in the dose of glyphosate combined with U+AMS was also observed for controls of 80% (C80). In the second trial, the addition of U+SA to glyphosate spray solution increased the control obtained at the lowest glyphosate rate (360 g ha-1), leveling it to the highest rate application (720 g ha-1) without adjuvants. These results show the complementary action of U and AMS to increase glyphosate efficacy to control D. insularis.

  19. Transcutaneous spinal DC stimulation reduces pain sensitivity in humans.

    Science.gov (United States)

    Meyer-Frießem, C H; Haag, L M; Schmidt-Wilcke, T; Magerl, W; Pogatzki-Zahn, E M; Tegenthoff, M; Zahn, P K

    2015-03-01

    Non-invasive approaches to pain management are needed to manage patient pain escalation and to providing sufficient pain relief. Here, we evaluate the potential of transcutaneous spinal direct current stimulation (tsDCS) to modulate pain sensitivity to electrical stimuli and mechanical pinpricks in 24 healthy subjects in a sham-controlled, single-blind study. Pain ratings to mechanical pinpricks and electrical stimuli were recorded prior to and at three time points (0, 30, and 60min) following 15min of anodal tsDCS (2.5mA, "active" electrode centered over the T11 spinous process, return electrode on the left posterior shoulder). Pain ratings to the pinpricks of the highest forces tested (128, 256, 512mN) were reduced at 30min and 60min following anodal tsDCS. These findings demonstrate that pain sensitivity in healthy subjects can be suppressed by anodal tsDCS and suggest that tsDCS may provide a non-invasive tool to manage mechanically-induced pain. PMID:25596439

  20. Glyphosate loss by runoff and its relationship with phosphorus fertilization.

    Science.gov (United States)

    Sasal, María Carolina; Demonte, Luisina; Cislaghi, Andrea; Gabioud, Emmanuel A; Oszust, José D; Wilson, Marcelo G; Michlig, Nicolás; Beldoménico, Horacio R; Repetti, María Rosa

    2015-05-13

    The aim of this study was to evaluate the relationship between glyphosate and phosphate fertilizer application and their contribution to surface water runoff contamination. The study was performed in Aquic Argiudoll soil (Tezanos Pinto series). Four treatments were assessed on three dates of rainfall simulation after fertilizer and herbicide application. The soluble phosphorus in runoff water was determined by a colorimetric method. For the determination of glyphosate and aminomethylphosphonic acid (AMPA), a method based on fluorenylmethyloxycarbonyl (FMOC) group derivatization, solid phase extraction (SPE) purification, and ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was employed. The application of phosphorus fertilizer resulted in an increased loss of glyphosate by runoff after 1 day of application. These results suggest the need for further study to understand the interactions and to determine appropriate application timing with the goal of reducing the pollution risk by runoff. PMID:25775388

  1. Influence of late emerging weeds in glyphosate-resistant corn

    OpenAIRE

    Nader Soltani; Robert E. Nurse; Eric Page; Wesley J. Everman; Christy L. Sprague; Peter H. Sikkema

    2013-01-01

    Fifteen field trials were conducted from 2009 to 2011 in Ontario, Canada and Michigan, USA to determine how long glyphosate-resistant corn needs to be kept weed-free after emergence to prevent yield loss. Data were separated into two environments based on when yield loss first occurred after glyphosate application. In Environment 1 (4/15 sites) yield was not reduced when corn was kept weed-free until the 4-leaf stage. However, in Environment 2 (11/15 sites) there was no yield loss when corn ...

  2. Micromorfologia foliar na análise da fitotoxidez por glyphosate em Eucalyptus grandis Leaf micromorphology in the analysis of glyphosate toxicity in Eucalyptus grandis

    Directory of Open Access Journals (Sweden)

    L.D. Tuffi Santos

    2009-01-01

    Full Text Available Foram avaliados os efeitos da deriva de formulações comerciais de glyphosate sobre a superfície foliar e o crescimento de clones de eucalipto. Mudas de seis clones foram submetidas a 129,6 g ha-1 de glyphosate das formulações comerciais Scout®, Roundup NA®, Roundup transorb® e Zapp QI®. Entre os clones não foram identificadas diferenças quanto à tolerância ao glyphosate. Plantas expostas à deriva simulada de Roundup transorb® e Zapp QI® apresentaram, respectivamente, a maior e menor porcentagem de intoxicação. Observou-se menor massa seca em plantas expostas ao glyphosate, independentemente da formulação, e menor altura naquelas expostas ao Scout® e ao Roundup transorb®. As características quantitativas da superfície foliar não foram afetadas pelo glyphosate. As alterações micromorfológicas ocorreram na ausência de danos visíveis e foram observadas em ambas as faces da epiderme, em todos os clones avaliados. Danos como erosão e aspecto amorfo das ceras epicuticulares e infestação por hifas fúngicas ocorreram, independentemente da formulação utilizada. A avaliação anatômica da superfície foliar foi relevante para descrição e interpretação dos danos causados pelo glyphosate. Os dados de crescimento e de intoxicação indicam o Zapp QI® como a formulação de menor risco para a cultura do eucalipto quanto aos efeitos indesejáveis da deriva.The effects of commercial glyphosate drift on the leaf surface and growth of eucalypt clones were evaluated. Seedlings of six clones were submitted to 129.6 g ha-1 sub-rate of commercial glyphosate formulations Scout®, Roundup NA®, Roundup transorb® and Zapp QI®. No differences in tolerance to glyphosate were observed among the clones. Plants exposed to simulated drift of Roundup transorb® and Zapp QI® presented the highest and lowest intoxication percentages, respectively. Plants exposed to glyphosate reduced dry biomass, regardless of the formulation, and also reduced height of the plants exposed to Scout® and Roundup transorb®. Leaf surface characteristics were not affected by glyphosate application. However, the micromorphological damages occurred prior to the appearance of visible symptoms, and were observed on both faces of the epidermis, in all clones tested. Damages such as erosion and amorphous aspect of epicuticular waxes and infestation of fungal hyphae occurred, independently of the formulation used. The anatomical evaluation of the leaf surface effectively described the damages caused by glyphosate. The growth and intoxication data indicate Zapp QI® formulation as presenting the lowest risk to eucalypt culture, in relation to the undesirable herbicide drift effects.

  3. Photosynthetic activity of coffee after application of glyphosate subdoses / Atividade fotossintética do cafeeiro após aplicação de subdoses de glyphosate

    Scientific Electronic Library Online (English)

    Felipe Paolinelli de, Carvalho; André Cabral, França; Vinícius Teixeira, Lemos; Evander Alves, Ferreira; José Barbosa dos, Santos; Antonio Alberto da, Silva.

    2013-03-01

    Full Text Available Para o controle de plantas daninhas em lavouras cafeeiras, os produtores utilizam herbicidas não-seletivos, como o glyphosate, empregado em aplicações dirigidas. Apesar de todos os cuidados com a aplicação, são constatados casos de intoxicação em plantas, sendo de fundamental importância o conhecime [...] nto dos efeitos sobre os processos fotossintéticos. Objetivou-se com este trabalho avaliar as características associadas à atividade fotossintética entre cultivares de cafeeiro submetidos a doses de glyphosate. O experimento foi conduzido em casa de vegetação utilizando-se três cultivares de cafeeiro (Coffea arabica): Acaiá (MG-6851), Catucaí Amarelo (2 SL) e Topázio (MG-1190) e, três subdoses do glyphosate (0,0; 115,2 e 460,8 g ha-1), em esquema fatorial 3 x 3. Em função da aplicação do herbicida observou-se redução de carbono interno, razão carbono interno e do ambiente, consumo de carbono e taxa fotossintética, aos 15 DAA na quarta folha. Na mesma folha aos 45 DAA, constatou-se menor consumo de carbono pelos cultivares. Na última folha apesar de inferiores concentrações de carbono, não obteve-se diferença no consumo e taxa fotossintética. O glyphosate resulta em danos metabólicos com efeitos transitórios sobre a atividade fotossintética, sendo o cultivar Acaiá o mais tolerante. Este efeito transitório pode resultar em danos prolongados e irreversíveis no crescimento da cultura. Abstract in english Farmers use non-selective herbicides, such as glyphosate, in directed applications to control weeds in coffee crops. Despite the precautions used during the application of herbicides, there are usually reports of poisoning in plantation areas. Moreover, it is fundamental to understand the effects of [...] glyphosate on photosynthetic processes. The present study aimed to evaluate the characteristics associated with the photosynthetic activity in coffee cultivars subjected to doses of glyphosate. The experiment was conducted in a greenhouse using three varieties of coffee (Coffea arabica), including Acaiá (MG-6851), Catucaí Amarelo (2 SL) and Topázio (MG-1190), and three subdoses of glyphosate (0.0, 115.2 and 460.8 g ha-1) in a 3 x 3 factorial scheme. Herbicide application led to reduced internal carbon, ratio between internal and environmental carbon, carbon consumption and photosynthetic rate at 15 days after application (DAA) in the fourth leaf. In the same leaf at 45 DAA, the carbon consumption of the cultivars was even less. Despite low carbon concentrations, no difference in consumption and photosynthetic rate was observed in the last leaf. Glyphosate caused metabolic damage with transitory effects on the photosynthetic rate; the Acaiá cultivar was the most tolerant. These transitory effects may result in irreversible and prolonged damage to crop growth.

  4. Glyphosate resistance: state of knowledge

    OpenAIRE

    Sammons, Robert Douglas; Gaines, Todd A

    2014-01-01

    Studies of mechanisms of resistance to glyphosate have increased current understanding of herbicide resistance mechanisms. Thus far, single-codon non-synonymous mutations of EPSPS (5-enolypyruvylshikimate-3-phosphate synthase) have been rare and, relative to other herbicide mode of action target-site mutations, unconventionally weak in magnitude for resistance to glyphosate. However, it is possible that weeds will emerge with non-synonymous mutations of two codons of EPSPS to produce an enzym...

  5. Glyphosate drift affects arbuscular mycorrhizal association in coffee / Deriva de glyphosate afeta a associação micorrízica arbuscular em cafeeiro

    Scientific Electronic Library Online (English)

    F.P., Carvalho; B.P., Souza; A.C., França; E.A., Ferreira; M.H.R., Franco; M.C.M., Kasuya; F.A., Ferreira.

    2014-12-01

    Full Text Available A associação micorrízica favorece o estabelecimento, a sobrevivência no campo e a nutrição da planta hospedeira, levando por consequência, a maior crescimento e produtividade. Todavia, o manejo de plantas daninhas no cafeeiro pode interferir nessa associação, podendo o emprego incorreto do glyphosat [...] e influenciar nesses benefícios da associação. Avaliou-se neste trabalho efeito da deriva do herbicida glyphosate no crescimento e estado nutricional de plantas de café arábica (Catuaí Vermelho IAC 99) inoculadas com fungos micorrízicos arbusculares (FMAs). Para isso, utilizou-se esquema fatorial 2 x 5, sendo mudas inoculadas ou não inoculadas com FMAs e cinco subdoses de glyphosate (0; 57,6; 115,2; 230,4; e 460,8 g ha-1 de glyphosate), em delineamento de blocos casualizados com cinco repetições. A inoculação foi efetuada na fase de produção de muda, com uma mistura de FMAs, Rhizophagus clarus e Gigaspora margarita; posteriormente ao transplantio, quando as plantas estavam com sete pares de folhas, aplicaram-se as subdoses de glyphosate. O herbicida causou fitointoxicação de até 60% em plantas não inoculadas e de 45% em plantas inoculadas com aplicação da maior dose de 460,8 g e.a. ha-1. Verificou-se efeito negativo no crescimento das plantas de café e do teor de fósforo delas com o aumento das doses de glyphosate, independentemente da inoculação. O herbicida reduziu o crescimento de plantas colonizadas pelos FMAs testados, bem como de fungos nativos, afetando negativamente a colonização micorrízica das plantas tratadas com o glyphosate. Abstract in english Mycorrhizal association promotes better survival and nutrition of colonized seedling on field, and consequently, increasing of productivity. However, the weed management can interfere on this association, due to incorrect use of glyphosate. This work has assessed the effects of glyphosate drift on t [...] he growth and nutrition of arabica coffee plants (Catuaí Vermelho - IAC 99) colonized with arbuscular mycorrhizal fungi (AMF). The experiment was conducted in 2 x 5 factorial scheme, and included inoculated and non-inoculated plants, and five glyphosate subdoses (0.0, 57.6, 115.2, 230.4, and 460.8 g ha-1 of glyphosate), in randomized blocks with five replication. The inoculation was carried during the greenhouse phase of seedlings production with a mixture of Rhizophagus clarus and Gigaspora margarita, and after to transplanting, when the plants had seven pairs of leaves, glyphosate subdoses were applied. The product caused intoxication in up to 60% of non-inoculated and 45% on inoculated plants, when the highest dose of 460.8 g a.e. ha-1 was applied. A negative effect was noted on the growth and phosphorus content of coffee plants, this effect increased depending on glyphosate subdose, but regardless of inoculation. Glyphosate drift reduces the growth and nutrition of plants colonized by species of AMF and native fungi, negatively affecting root colonization of plants treated.

  6. Selectivity of glyphosate tank mixtures for RR soybean / Seletividade de glyphosate em misturas em tanque para soja RR

    Scientific Electronic Library Online (English)

    D.G, Alonso; J, Constantin; R.S, Oliveira Jr; J.G.Z, Arantes; S.D, Cavalieri; G, Santos; F.A, Rios; L.H.M, Franchini.

    2011-12-01

    Full Text Available A mistura de ingredientes ativos de diferentes mecanismos de ação é uma ferramenta essencial para prevenir ou manejar áreas com plantas daninhas resistentes. No entanto é importante que tais associações forneçam adequada seletividade para a cultura. O objetivo deste trabalho foi avaliar a seletivida [...] de do glyphosate a soja RR, e verificar também, se existe seletividade a misturas com outros ingredientes ativos, aplicados em pós-emergência, visando novas estratégias de controle que poderão ser empregadas no cultivo da soja RR. Os herbicidas e respectivas doses (g ha-1) avaliadas foram: glyphosate isolado (720, 960, 1.200 e 1.440) e as misturas de glyphosate (960) com cloransulam-methyl (30,24), fomesafen (125), lactofen (72), chlorimuron-ethyl (12,5), flumiclorac-pentyl (30), bentazon (480) e imazethapyr (80). Todos os tratamentos foram aplicados em dose única em pós-emergência quando a soja estava no estádio V2 a V3. Tratamentos com glyphosate isolado ou em mistura com herbicidas pós-emergentes aplicados em dose única promoveram efeitos visuais de fitointoxicação quando aplicados na soja resistente ao glyphosate. Efeitos como redução na altura das plantas, no fechamento da cultura, no número de vagens por planta e na massa de cem grãos puderam ser observados. Entretanto, os efeitos relatados ao desenvolvimento das plantas foram na sua maioria transientes, não persistindo durante todo ciclo da cultura. Dentre os tratamentos estudados, somente a mistura entre glyphosate e lactofen não apresentou seletividade à cultura, promovendo efeitos negativos na maioria das características estudadas e consequentemente reduzindo a produtividade de grãos. Abstract in english An active ingredients mixture of different action mechanisms is an essential tool to prevent or manage areas with resistant weeds. However, it is important that such a mixture provides adequate selectivity to the crop. The aim of this work was to evaluate glyphosate selectivity to glyphosate-resista [...] nt (RR) soybean, and also verify if there is selectivity in mixtures with other active ingredients applied postemergence aimed at new control strategies, which might be used in RR soybean cultivation. The herbicides and respective rates (g ha-1) evaluated were: glyphosate (720, 960, 1,200, and 1,440), and the mixtures of glyphosate (960) with cloransulam-methyl (30.24), fomesafen (125), lactofen (72), chlorimuron-ethyl (12.5), flumiclorac-pentyl (30), bentazon (480), or imazethapyr (80). All treatments were applied in postemergence when the soybean crop was at V2 to V3 stage. Treatments with glyphosate or in mixtures with postemergent herbicides showed visual effects of phytotoxicity when applied to the glyphosate-resistant soybean. Effects such as reduction in plant height, crop closure, number of pods per plant, and hundred grain weight could be observed. However, the effects related to plant development were mostly transient and did not persist during the crop cycle. Among the studied treatments, only the mixture of glyphosate and lactofen was not selective to the crop, promoting negative effects on most characteristics analyzed and consequently reducing grain yield.

  7. Selectivity of glyphosate tank mixtures for RR soybean Seletividade de glyphosate em misturas em tanque para soja RR

    Directory of Open Access Journals (Sweden)

    D.G Alonso

    2011-12-01

    Full Text Available An active ingredients mixture of different action mechanisms is an essential tool to prevent or manage areas with resistant weeds. However, it is important that such a mixture provides adequate selectivity to the crop. The aim of this work was to evaluate glyphosate selectivity to glyphosate-resistant (RR soybean, and also verify if there is selectivity in mixtures with other active ingredients applied postemergence aimed at new control strategies, which might be used in RR soybean cultivation. The herbicides and respective rates (g ha-1 evaluated were: glyphosate (720, 960, 1,200, and 1,440, and the mixtures of glyphosate (960 with cloransulam-methyl (30.24, fomesafen (125, lactofen (72, chlorimuron-ethyl (12.5, flumiclorac-pentyl (30, bentazon (480, or imazethapyr (80. All treatments were applied in postemergence when the soybean crop was at V2 to V3 stage. Treatments with glyphosate or in mixtures with postemergent herbicides showed visual effects of phytotoxicity when applied to the glyphosate-resistant soybean. Effects such as reduction in plant height, crop closure, number of pods per plant, and hundred grain weight could be observed. However, the effects related to plant development were mostly transient and did not persist during the crop cycle. Among the studied treatments, only the mixture of glyphosate and lactofen was not selective to the crop, promoting negative effects on most characteristics analyzed and consequently reducing grain yield.A mistura de ingredientes ativos de diferentes mecanismos de ação é uma ferramenta essencial para prevenir ou manejar áreas com plantas daninhas resistentes. No entanto é importante que tais associações forneçam adequada seletividade para a cultura. O objetivo deste trabalho foi avaliar a seletividade do glyphosate a soja RR, e verificar também, se existe seletividade a misturas com outros ingredientes ativos, aplicados em pós-emergência, visando novas estratégias de controle que poderão ser empregadas no cultivo da soja RR. Os herbicidas e respectivas doses (g ha-1 avaliadas foram: glyphosate isolado (720, 960, 1.200 e 1.440 e as misturas de glyphosate (960 com cloransulam-methyl (30,24, fomesafen (125, lactofen (72, chlorimuron-ethyl (12,5, flumiclorac-pentyl (30, bentazon (480 e imazethapyr (80. Todos os tratamentos foram aplicados em dose única em pós-emergência quando a soja estava no estádio V2 a V3. Tratamentos com glyphosate isolado ou em mistura com herbicidas pós-emergentes aplicados em dose única promoveram efeitos visuais de fitointoxicação quando aplicados na soja resistente ao glyphosate. Efeitos como redução na altura das plantas, no fechamento da cultura, no número de vagens por planta e na massa de cem grãos puderam ser observados. Entretanto, os efeitos relatados ao desenvolvimento das plantas foram na sua maioria transientes, não persistindo durante todo ciclo da cultura. Dentre os tratamentos estudados, somente a mistura entre glyphosate e lactofen não apresentou seletividade à cultura, promovendo efeitos negativos na maioria das características estudadas e consequentemente reduzindo a produtividade de grãos.

  8. 75 FR 17768 - Glyphosate From China

    Science.gov (United States)

    2010-04-07

    ...COMMISSION [Investigation No. 731-TA-1178 (Preliminary)] Glyphosate From China AGENCY: United States International Trade Commission...is materially retarded, by reason of imports from China of glyphosate, provided for in subheadings 2931.00.90 and...

  9. 75 FR 24969 - Glyphosate From China

    Science.gov (United States)

    2010-05-06

    ...COMMISSION [Investigation No. 731-TA-1178 (Preliminary)] Glyphosate From China AGENCY: United States International Trade Commission...gives notice that its antidumping investigation concerning glyphosate from China (investigation No. 731-TA-1178...

  10. THE REMOVAL OF GLYPHOSATE FROM DRINKING WATER

    Science.gov (United States)

    The effectiveness of granulated activated carbon (GAC), packed activated carbon (PAC), conventional treatment, membranes, and oxidation for removing glyphosate from natural waters is evaluated. Results indicate that GAC and PAC are not effective in removing glyphosate, while oxid...

  11. 75 FR 24969 - Glyphosate From China

    Science.gov (United States)

    2010-05-06

    ... From the Federal Register Online via the Government Printing Office INTERNATIONAL TRADE COMMISSION Glyphosate From China AGENCY: United States International Trade Commission. ACTION: Notice of withdrawal of... its antidumping investigation concerning glyphosate from China (investigation No....

  12. Glyphosate inhibits rust diseases in glyphosate-resistant wheat and soybean

    OpenAIRE

    Feng, Paul C. C.; Baley, G. James; Clinton, William P.; Bunkers, Greg J.; Alibhai, Murtaza F.; Paulitz, Timothy C.; Kidwell, Kimberlee K.

    2005-01-01

    Glyphosate is a broad-spectrum herbicide used for the control of weeds in glyphosate-resistant crops. Glyphosate inhibits 5-enolpyruvyl shikimate 3-phosphate synthase, a key enzyme in the synthesis of aromatic amino acids in plants, fungi, and bacteria. Studies with glyphosate-resistant wheat have shown that glyphosate provided both preventive and curative activities against Puccinia striiformis f. sp. tritici and Puccinia triticina, which cause stripe and leaf rusts, respectively, in wheat. ...

  13. Atrazine and glyphosate dynamics in a lotic ecosystem: the common snapping turtle as a sentinel species.

    Science.gov (United States)

    Douros, Derrick L; Gaines, Karen F; Novak, James M

    2015-03-01

    Atrazine and glyphosate are two of the most common pesticides used in the US Midwest that impact water quality via runoff, and the common snapping turtle (Chelydra serpentina) is an excellent indicator species to monitor these pesticides especially in lotic systems. The goals of this study were to (1) quantify atrazine, the atrazine metabolite diaminochlorotriazine (DACT), and glyphosate burdens in common snapping turtle tissue from individuals collected within the Embarras River in Illinois; (2) quantify atrazine, DACT, and glyphosate loads in water from the aquatic habitats in which common snapping turtles reside; and (3) investigate tissue loads based on turtle morphology and habitat choice. Concentrations of atrazine, DACT, and glyphosate in tissue did not show any relationship with lake habitat, carapace length, width, or mass. Both atrazine and glyphosate tissue samples varied as a function of site (river vs. lake), but DACT did not. Atrazine and glyphosate concentrations in water samples showed a linear effect on distance from the reservoir spillway and a deviation from linearity. Water column concentrations of all three contaminants varied across capture sites, but atrazine water concentration did not influence DACT water concentration nor did it exhibit a site interaction. Water atrazine and glyphosate concentrations were greater than tissue concentrations, whereas DACT water and tissue concentrations did not differ. This study showed that turtles are useful in long-term pesticide monitoring, and because DACT as a metabolite is less sensitive to variation, it should be considered as a preferred biomarker for pesticide runoff. PMID:25678354

  14. Contrast Sensitivity Is Reduced in Children with Infantile Spasms

    Science.gov (United States)

    Mirabella, Giuseppe; Morong, Sharon; Buncic, J. Raymond; Snead, O. Carter; Logan, William J.; Weiss, Shelly K.; Abdolell, Mohamed; Westall, Carol A.

    2013-01-01

    Purpose To investigate whether visual deficits in children with infantile spasm (IS) are the result of seizure activity or of treatment with the anticonvulsant drug vigabatrin (VGB). Methods Vision function was determined in three experiments by determining peak contrast sensitivity (CS) and grating acuity (GA) with the sweep visual evoked potential. Cross-sectional study A: 34 children, including 11 patients with childhood epilepsy with exposure to VGB for at least 6 months, 10 with childhood epilepsy exposed to antiepileptic drugs other than VGB, and 13 normally developing children. Cross-sectional study B: 32 children, including 16 with IS naïve to VGB and 16 normally developing children. Longitudinal study: seven children with IS naïve to VGB, with subsequent follow-up 5 to 10 months after starting VGB. Results In cross-sectional study A, the median CS was reduced by 0.5 log units (P = 0.025) in children with epilepsy exposed to VGB compared with those exposed to other antiepileptic drugs and normally developing children. In cross-sectional study B, the median CS was reduced by 0.25 log units (P = 0.0015) in children with IS (VGB naïve) compared with normally developing children. Longitudinal assessment showed no decrease in CS in children with IS who were followed up 5 to 10 months after starting VGB. There was no difference in GA among groups in any of the experiments. Conclusions Patients with IS have CS deficits, but a sparing of GA. This deficit is present before VGB treatment and does not worsen with treatment onset. Results suggest that visual dysfunction is largely the result of the seizures themselves. PMID:17652730

  15. Reduced sensitivity of older adults to affective mismatches.

    Science.gov (United States)

    Jiang, Yang; Vagnini, Victoria; Clark, Jessica; Zhang, Qin

    2007-01-01

    The present study investigated age-related differences in emotional processing by using a paradigm of affective priming. Eighteen, right-handed, younger (mean age 22) and 15 older (mean age 68) subjects pressed buttons to indicate pleasantness of target words. The valence of each prime-target pair was congruent (e.g., win-love), incongruent (e.g., love-loss), or neutral (time-flower). Two sets of 720 prime-target pairs used either affective words or pictures as primes, and affect words as targets. We included well-matched positive and negative valence pairs in all congruent, neutral, and incongruent conditions, and controlled for possible contamination by semantic meaning, word frequency, and repetition effects. The response time (RT) results revealed that young participants responded faster to the targets in affectively congruent conditions than in incongruent conditions. In older participants, the responses to target words were indifferent to all valence congruency conditions. The age effect in affective priming largely reflects reduced sensitivity to affective mismatches among older adults. Intriguingly, emotional Stroop effect and some perceptual priming have been linked to increased interferences and mismatches in older adults. The age-related changes in affective, perceptual, and semantic processes are discussed. PMID:17619749

  16. Micromorfologia foliar na análise da fitotoxidez por glyphosate em Eucalyptus grandis / Leaf micromorphology in the analysis of glyphosate toxicity in Eucalyptus grandis

    Scientific Electronic Library Online (English)

    L.D., Tuffi Santos; B.F., Sant' Anna-Santos; R.M.S.A., Meira; F.A., Ferreira; R.A.S.T., Tiburcio; E.C.F., Silva.

    Full Text Available Foram avaliados os efeitos da deriva de formulações comerciais de glyphosate sobre a superfície foliar e o crescimento de clones de eucalipto. Mudas de seis clones foram submetidas a 129,6 g ha-1 de glyphosate das formulações comerciais Scout®, Roundup NA®, Roundup transorb® e Zapp QI®. Entre os clo [...] nes não foram identificadas diferenças quanto à tolerância ao glyphosate. Plantas expostas à deriva simulada de Roundup transorb® e Zapp QI® apresentaram, respectivamente, a maior e menor porcentagem de intoxicação. Observou-se menor massa seca em plantas expostas ao glyphosate, independentemente da formulação, e menor altura naquelas expostas ao Scout® e ao Roundup transorb®. As características quantitativas da superfície foliar não foram afetadas pelo glyphosate. As alterações micromorfológicas ocorreram na ausência de danos visíveis e foram observadas em ambas as faces da epiderme, em todos os clones avaliados. Danos como erosão e aspecto amorfo das ceras epicuticulares e infestação por hifas fúngicas ocorreram, independentemente da formulação utilizada. A avaliação anatômica da superfície foliar foi relevante para descrição e interpretação dos danos causados pelo glyphosate. Os dados de crescimento e de intoxicação indicam o Zapp QI® como a formulação de menor risco para a cultura do eucalipto quanto aos efeitos indesejáveis da deriva. Abstract in english The effects of commercial glyphosate drift on the leaf surface and growth of eucalypt clones were evaluated. Seedlings of six clones were submitted to 129.6 g ha-1 sub-rate of commercial glyphosate formulations Scout®, Roundup NA®, Roundup transorb® and Zapp QI®. No differences in tolerance to glyph [...] osate were observed among the clones. Plants exposed to simulated drift of Roundup transorb® and Zapp QI® presented the highest and lowest intoxication percentages, respectively. Plants exposed to glyphosate reduced dry biomass, regardless of the formulation, and also reduced height of the plants exposed to Scout® and Roundup transorb®. Leaf surface characteristics were not affected by glyphosate application. However, the micromorphological damages occurred prior to the appearance of visible symptoms, and were observed on both faces of the epidermis, in all clones tested. Damages such as erosion and amorphous aspect of epicuticular waxes and infestation of fungal hyphae occurred, independently of the formulation used. The anatomical evaluation of the leaf surface effectively described the damages caused by glyphosate. The growth and intoxication data indicate Zapp QI® formulation as presenting the lowest risk to eucalypt culture, in relation to the undesirable herbicide drift effects.

  17. Alteration in the cytokine levels and histopathological damage in common carp induced by glyphosate.

    Science.gov (United States)

    Ma, Junguo; Li, Xiaoyu

    2015-06-01

    Glyphosate is one of the most frequently used herbicides, and it has been demonstrated to generate a series of toxicological problems in animals and humans. However, relatively little is known about the effects of glyphosate on the immune system of fish. In the present study, the acute toxicity of glyphosate on common carp was first determined; then, the contents of interferon-? (IFN-?), interleukin-1? (IL-1?), and tumor necrosis factor -? (TNF-?) and histopathological alterations in the liver, kidneys, and spleen of common carp exposed to 52.08 or 104.15 mg L(-1) of glyphosate for 168 h were also determined and evaluated. The results of the acute toxicity tests showed that the 96 h LC50 of glyphosate for common carp was 520.77 mg L(-1). Moreover, sub-acute exposure of glyphosate altered the contents of IFN-?, IL-1?, and TNF-? in fish immune organs. For example, there was a remarkable increase in the IFN-? content in the kidneys, while there was a decrease in the liver and spleen. The IL-1? content increased in liver and kidneys, but it decreased in the spleen, and TNF-? mainly increased in the fish liver, kidneys, and spleen. In addition, glyphosate-exposure also caused remarkable histopathological damage in the fish liver, kidneys, and spleen. These results suggest that glyphosate-caused cytokine alterations may result in an immune suppression or excessive activation in the treated common carp as well as may cause immune dysfunction or reduced immunity. In conclusion, glyphosate has immunotoxic effects on common carp. PMID:25747155

  18. The current status and environmental impacts of glyphosate-resistant crops: a review.

    Science.gov (United States)

    Cerdeira, Antonio L; Duke, Stephen O

    2006-01-01

    Glyphosate [N-(phosphonomethyl) glycine]-resistant crops (GRCs), canola (Brassica napus L.), cotton (Gossypium hirsutum L.), maize (Zea mays L.), and soybean [Glycine max (L.) Merr.] have been commercialized and grown extensively in the Western Hemisphere and, to a lesser extent, elsewhere. Glyphosate-resistant cotton and soybean have become dominant in those countries where their planting is permitted. Effects of glyphosate on contamination of soil, water, and air are minimal, compared to some of the herbicides that they replace. No risks have been found with food or feed safety or nutritional value in products from currently available GRCs. Glyphosate-resistant crops have promoted the adoption of reduced- or no-tillage agriculture in the USA and Argentina, providing a substantial environmental benefit. Weed species in GRC fields have shifted to those that can more successfully withstand glyphosate and to those that avoid the time of its application. Three weed species have evolved resistance to glyphosate in GRCs. Glyphosate-resistant crops have greater potential to become problems as volunteer crops than do conventional crops. Glyphosate resistance transgenes have been found in fields of canola that are supposed to be non-transgenic. Under some circumstances, the largest risk of GRCs may be transgene flow (introgression) from GRCs to related species that might become problems in natural ecosystems. Glyphosate resistance transgenes themselves are highly unlikely to be a risk in wild plant populations, but when linked to transgenes that may impart fitness benefits outside of agriculture (e.g., insect resistance), natural ecosystems could be affected. The development and use of failsafe introgression barriers in crops with such linked genes is needed. PMID:16899736

  19. Degradation Dynamics of Glyphosate in Different Types of Citrus Orchard Soils in China

    Directory of Open Access Journals (Sweden)

    Changpeng Zhang

    2015-01-01

    Full Text Available Glyphosate formulations that are used as a broad-spectrum systemic herbicide have been widely applied in agriculture, causing increasing concerns about residues in soils. In this study, the degradation dynamics of glyphosate in different types of citrus orchard soils in China were evaluated under field conditions. Glyphosate soluble powder and aqueous solution were applied at 3000 and 5040 g active ingredient/hm2, respectively, in citrus orchard soils, and periodically drawn soil samples were analyzed by high performance liquid chromatography. The results showed that the amount of glyphosate and its degradation product aminomethylphosphonic acid (AMPA in soils was reduced with the increase of time after application of glyphosate formulations. Indeed, the amount of glyphosate in red soil from Hunan and Zhejiang Province, and clay soil from Guangxi Province varied from 0.13 to 0.91 µg/g at 42 days after application of aqueous solution. Furthermore, the amount of glyphosate in medium loam from Zhejiang and Guangdong Province, and brown loam from Guizhou Province varied from less than 0.10 to 0.14 µg/g, while the amount of AMPA varied from less than 0.10 to 0.99 µg/g at 42 days after application of soluble powder. Overall, these findings demonstrated that the degradation dynamics of glyphosate aqueous solution and soluble powder as well as AMPA depend on the physicochemical properties of the applied soils, in particular soil pH, which should be carefully considered in the application of glyphosate herbicide.

  20. Glyphosate Accumulation and Detrimental Effects on Coffea Arabica

    DEFF Research Database (Denmark)

    Schrübbers, Lars Christoph

    2015-01-01

    Coffee is one of the most popular beverages worldwide and a highly traded commodity. In order to maintain a high yield of the perennial crop, weed competition for resources needs to be reduced. For this purpose herbicides are commonly applied, with glyphosate being one of the most prominent herbicides in coffee fields. Glyphosate [N-(phosphonomethyl)glycine], the active ingredient in Roundup®, is characterized as systemic, non-selective, with a broad weed spectrum, inhibiting the enzyme 5-enolpy...

  1. Control of glyphosate resistant giant ragweed in soybean with preplant herbicides

    OpenAIRE

    Joanna Follings; Nader Soltani; Robinson, Darren E.; François J. Tardif; Mark B. Lawton; Peter H. Sikkema

    2013-01-01

    Giant ragweed was the first glyphosate resistant weed identified in Canada. It is a very competetive weed in row crop production and has been found to drastically reduce yields of soybean; therefore, control of this competitive weed is essential. The objective of this study was to determine effective control options for glyphosate resistant giant ragweed in soybean with herbicides applied preplant. Eighteen herbicide combinations were evaluated in field studies conducted in 2011 and 2012 at ...

  2. Effects of Glyphosate on Metabolism of Phenolic Compounds: V. l-alpha-AMINOOXY-beta-PHENYLPROPIONIC ACID AND GLYPHOSATE EFFECTS ON PHENYLALANINE AMMONIA-LYASE IN SOYBEAN SEEDLINGS.

    Science.gov (United States)

    Duke, S O; Hoagland, R E; Elmore, C D

    1980-01-01

    The phenylalanine ammonia-lyase (PAL) inhibitor l-alpha-aminooxy-beta-phenylpropionic acid (AOPP) was root-fed to light-exposed soybean seedlings alone or with glyphosate [N-(phosphonomethyl)glycine] to test further the hypothesis that PAL activity is involved in the mode of action of glyphosate. Extractable PAL activity was increased by 0.01 and 0.1 millimolar AOPP. AOPP reduced total soluble hydroxyphenolic compound levels and increased phenylalanine and tyrosine levels, indicating that in vivo PAL activity was inhibited by AOPP. The increase in extractable PAL caused by AOPP may be a result of decreased feedback inhibition of PAL synthesis by cinnamic acid and/or its derivatives. AOPP alone had no effect on growth (fresh weight and elongation) at either concentration, but at 0.1 millimolar it slightly alleviated growth (fresh weight) inhibition caused by 0.5 millimolar glyphosate after 4 days. Reduction of the free pool of phenylalanine by glyphosate was reversed by AOPP. These results indicate that glyphosate exerts some of its effects through reduction of aromatic amino acid pools through increases in PAL activity and that not all growth effects of glyphosate are due to reductions of aromatic amino acids. PMID:16661135

  3. Dessecação de plantas daninhas com glyphosate em mistura com ureia ou sulfato de amônio Weed desiccation with glyphosate mixed with urea or ammonium sulfate

    Directory of Open Access Journals (Sweden)

    S.J.P. Carvalho

    2009-06-01

    Full Text Available O glyphosate é um herbicida não-seletivo, sistêmico, usado para controle de plantas daninhas anuais e perenes em todo o mundo. A absorção da molécula do glyphosate ocorre pelos tecidos fotossinteticamente ativos das plantas, porém alguns fatores podem reduzir sua eficácia, como a morfologia e diversidade de espécies, chuva após aplicação, qualidade da água e misturas em tanque com outros defensivos, entre outros. Objetivou-se com este trabalho avaliar a influência da adição de sulfato de amônio ou ureia em calda na eficácia do herbicida glyphosate para dessecação de plantas daninhas. Dois experimentos foram desenvolvidos em Piracicaba - SP, com aplicações de glyphosate (720 e 1.440 g ha-1 isolado ou combinado com duas doses de sulfato de amônio (7,5 e 15,0 g L-1 ou ureia (2,5 e 5,0 g L-1 sobre as plantas daninhas: apaga-fogo (Alternanthera tenella e capim-massambará (Sorghum halepense. Para a espécie menos suscetível ao herbicida (capim-massambará, a adição de fontes nitrogenadas à menor dose de glyphosate acelerou a morte das plantas, elevando os níveis de controle em até 7,3% na avaliação de 21 dias após aplicação (DAA dos tratamentos. Contudo, os efeitos não foram observados nas avaliações de controle, massa fresca e seca, conduzidas aos 28 DAA. A dose recomendada de glyphosate para cada espécie proporcionou controle satisfatório, sem a necessidade de adição de sulfato de amônio ou ureia.Glyphosate is a non-selective systemic herbicide used to control annual and perennial weeds worldwide. Molecule absorption occurs through the plant's photosynthetically-active tissues; however, some factors might reduce its efficacy, such as morphology and specific diversity, rain after application, water quality and tank mixtures with other chemicals. Thus, this work aimed to evaluate the influence of ammonium sulfate or urea addiction to spray tank on glyphosate efficacy for weed desiccation. Two trials were carried out in Piracicaba - SP, with applications of glyphosate (720 and 1440 g ha-1 alone or combined with two rates of ammonium sulfate (7.5 and 15.0 g L-1 or urea (2.5 and 5.0 g L-1, over the weeds Alternanthera tenella and Sorghum halepense. For the least susceptible species (S. halepense, the addition of nitrogen sources to the lower rate of glyphosate accelerated plant death, increasing the control levels up to 7.3%, at 21 days after application (DAA. However, the effects were not observed when control, fresh and dry mass were evaluated at 28 DAA. Glyphosate recommended rate for each species promoted appropriate control, without the need to add ammonium sulfate or urea.

  4. Glyphosate catabolism by Pseudomonas sp

    International Nuclear Information System (INIS)

    The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing [3-14C] glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO2. Fractionation of stationary phase cells labeled with [3-14C]glyphosate revealed that from 45-47% of the assimilated C3 carbon is distributed to proteins and that amino acids methionine and serine are highly labeled. The nucleic acid bases adenine and guanine received 90% of the C3 label that was incorporated into nucleic acids, and the only pyrimidine base labeled was thymine. Pulse labeling of PG2982 cells with [3-14C]glyphosate revealed that [3-14C]sarcosine is an intermediate in glyphosate degradation. Examination of crude extracts prepared from PG2982 cells revealed the presence of an enzyme that oxidizes sarcosine to glycine and formaldehyde. These results indicate that the first step in glyphosate degradation by PG2982 is cleavage of the carbon-phosphorus bond, resulting in the release of sarcosine and a phosphate group. The phosphate group is utilized as a source of phosphorus, and the sarcosine is degraded to glycine and formaldehyde. Phosphonate utilization by Pseudomonas sp. PG2982 was investigated. Each of the ten phosphonates tested were utilized as a sole source of phosphorus by PG2982. Representative compounds tested included alkylphosphonates, 1-amino-substituted alkylphosphonates, amino-terminal phosphonates, and an arylphosphonate. PG2982 cultures degraded phenylphosphonate to benzene and produced methane from methylphosphonate. The data indicate that PG2982 is capable of cleaving the carbon-phosphorus bond of several structurally different phosphonates

  5. Beam-shaping element with reduced sensitivity to input variations.

    Science.gov (United States)

    Chen, Y; Li, D; Sheng, Y

    1997-01-20

    We designed and fabricated a diffractive element for high-power laser beam shaping whose output is less sensitive to variations of input intensity and phase distributions. The choice of the initial solution is used as a degree of freedom to conduct the iterations to converge to a suboptimal solution that has the required property. We determined the initial phase by an aperture subdivision and stationary phase method, which is less sensitive to input variations. Experimental results are shown. PMID:18250708

  6. Ananas erectifolius Growth Under Effect of Glyphosate Low Doses

    Directory of Open Access Journals (Sweden)

    Cleber Daniel de Goes Maciel

    2009-04-01

    Full Text Available Amazonian native plant, Ananas erectifolius has been a specie of great interest for automobile industry, due to the fibers contained in its leaves that show resistance, softness and reduced weight. Some studies about simulation of glyphosate drift have been demonstrating the occurrence of tolerance and/or incentives of dossel growth of some vegetable species. This way, with the objective of evaluating the effects of glyphosate subdoses application in growth, development and yield of Ananas erectifolius an experiment was conducted in field conditions at Fazenda Pematec Triangel do Brasil Ltda, Santarém County, PA State. Studied treatments were constituted by glyphosate application in the concentrations of 0.0; 11.2; 22.5; 45.0; 90.0; 180.0; 360.0 g a.e. ha-1 and a hoe check. Ananas erectifolius plants presented low tolerance to glyphosate herbicide, and superior subdoses to 45.0 g a.e. ha-1 promoted the most significant reductions of benefitted leaves yield when applied in post-emergency. None of the studied subdoses promoted incentive or increase of Ananas erectifolius plants vegetative development.

  7. Glyphosate herbicide affects belowground interactions between earthworms and symbiotic mycorrhizal fungi in a model ecosystem

    Science.gov (United States)

    Zaller, Johann G.; Heigl, Florian; Ruess, Liliane; Grabmaier, Andrea

    2014-07-01

    Herbicides containing glyphosate are widely used in agriculture and private gardens, however, surprisingly little is known on potential side effects on non-target soil organisms. In a greenhouse experiment with white clover we investigated, to what extent a globally-used glyphosate herbicide affects interactions between essential soil organisms such as earthworms and arbuscular mycorrhizal fungi (AMF). We found that herbicides significantly decreased root mycorrhization, soil AMF spore biomass, vesicles and propagules. Herbicide application and earthworms increased soil hyphal biomass and tended to reduce soil water infiltration after a simulated heavy rainfall. Herbicide application in interaction with AMF led to slightly heavier but less active earthworms. Leaching of glyphosate after a simulated rainfall was substantial and altered by earthworms and AMF. These sizeable changes provide impetus for more general attention to side-effects of glyphosate-based herbicides on key soil organisms and their associated ecosystem services.

  8. Influence of glyphosate in planktonic and biofilm growth of Pseudomonas aeruginosa

    Scientific Electronic Library Online (English)

    Ilana Schneider, Lima; Nicole Carmo, Baumeier; Rosimeire Takaki, Rosa; Patrícia Maria Stuelp, Campelo; Edvaldo Antonio Ribeiro, Rosa.

    2014-09-01

    Full Text Available This study evaluated the impact of different concentrations of glyphosate (Rondup®) on planktonic and biofilm growth of P. aeruginosa. Aerobic and anaerobic cultures of P. aeruginosa ATCC®15442 inoculated in MHB + glyphosate (0.845 ppm, 1.690 ppm, 8.45 ppm, 16.90 ppm, 84.50 ppm, 169 ppm, 845 ppm, an [...] d 1690 ppm) and cultured in normoxia and anoxia, following their OD560nm every hour for 24 h. Biofilms of adapted cells were formed in the presence of glyphosate (0.845 to 1690 ppm) in normoxia and anoxia for 36 h. Glyphosate at concentrations higher than 84.5 ppm reduces the cell density of planktonic aerobic cultures (p 0.05), and more pronounced over 169 ppm. Anaerobic biofilms have their growth more readily favored (p

  9. The effect of glyphosate on import into a sink leaf of sugar beet

    International Nuclear Information System (INIS)

    The basis for glyphosate inducted limitation of carbon import into developing leaves was studied in sugar beet. To separate the effects of the herbicide on export from those on import, glyphosate was supplied to a developing leaf from two exporting source leaves which fed the sink leaf. Carbon import into the sink leaf was determined by supplying 14CO2 to a third source leaf which also supplies carbon to the monitored sink leaf. Import into the sink leaf decreased within 2 to 3 h after glyphosate application, even though photosynthesis and export in the source leaf supplying 14C were unaffected. Reduced import into the sink leaf was accompanied by increased import by the tap root. Elongation of the sink leaf was only slightly decreased following arrival of glyphosate. Photosynthesis by the sink leaf was not inhibited. The results to data support the view that import is slowed by the inhibition of synthesis of structural or storage compounds in the developing leaves

  10. Early Detection of Crop Injury from Glyphosate on Soybean and Cotton Using Plant Leaf Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Feng Zhao

    2014-02-01

    Full Text Available In this paper, we aim to detect crop injury from glyphosate, a herbicide, by both traditionally used spectral indices and newly extracted features with leaf hyperspectral reflectance data for non-Glyphosate-Resistant (non-GR soybean and non-GR cotton. The new features were extracted by canonical analysis technique, which could provide the largest separability to distinguish the injured leaves from the healthy ones. Spectral bands used for constructing these new features were selected based on the sensitivity analysis results of a physically-based leaf radiation transfer model (leaf optical PROperty SPECTra model, PROSPECT, which could help extend the effectiveness of these features to a wide range of leaf structures and growing conditions. This approach has been validated with greenhouse measured data acquired in glyphosate treatment experiments. Results indicated that glyphosate injury could be detected by NDVI (Normalized Difference Vegetation Index, RVI (Ratio Vegetation Index, SAVI (Soil Adjusted Vegetation Index, and DVI (Difference Vegetation Index in 48 h After the Treatment (HAT for soybean and in 72 HAT for cotton, but the other spectral indices either showed little use for separation, or did not show consistent separation for healthy and injured soybean and cotton. Compared with the traditional spectral indices, the new features were more feasible for the early detection of glyphosate injury, with leaves sprayed with a higher rate of glyphosate solution having larger feature values. This trend became more and more pronounced with time. Leaves sprayed with different glyphosate rates showed some separability 24 HAT using the new features and could be totally distinguished at and beyond 48 HAT for both soybean and cotton. These findings demonstrated the feasibility of applying leaf hyperspectral reflectance measurements for the early detection of glyphosate injury using these newly proposed features.

  11. Glyphosate translocation in herbicide tolerant plants Translocação do glyphosate em plantas tolerantes ao herbicida

    OpenAIRE

    L Galon; E.A. Ferreira; I. Aspiazú; G. Concenço; A.F Silva; Silva, A. A.; L. VARGAS

    2013-01-01

    The objective of this study was to evaluate glyphosate translocation in glyphosate-tolerant weed species (I. nil, T. procumbens and S. latifolia) compared to glyphosate-susceptible species (B. pilosa). The evaluations of 14C-glyphosate absorption and translocation were performed at 6, 12, 36 and 72 hours after treatment (HAT) in I. nil and B. pilosa, and only at 72 HAT in the species T. procumbens and S. latifolia. The plants were collected and fractionated into application leaf, other leaves...

  12. GLYPHOSATE REMOVAL FROM DRINKING WATER

    Science.gov (United States)

    Activated-carbon, oxidation, conventional-treatment, filtration, and membrane studies are conducted to determine which process is best suited to remove the herbicide glyphosate from potable water. Both bench-scale and pilot-scale studies are completed. Computer models are used ...

  13. Blocking facial mimicry reduces perceptual sensitivity for facial expressions.

    Science.gov (United States)

    Ipser, Alberta; Cook, Richard

    2015-09-01

    Built on models of 'action understanding', motor theories of expression perception propose that facial simulation, a process similar to covert imitation, aids perception and interpretation of others' facial expressions. As predicted by these accounts, some reports suggest that blocking facial mimicry impairs expression recognition. However, these reports have been criticized and motor theories remain controversial. Crucially, it remains to be determined whether the labeling errors observed reflect a loss of perceptual sensitivity - a genuine perceptual phenomenon - or whether they are a product of response bias. The current study addressed this question using a novel psychophysical paradigm, where observers judged whether smiles drawn from a morph continuum were sincere or insincere. In Experiment 1, we confirmed that cues from both the eye and mouth regions contribute to sincerity judgments. Experiment 2 measured discrimination of smile sincerity across free-viewing and blocked-mimicry conditions. In the blocked-mimicry condition, participants pronounced vowel sounds during stimulus presentation, thereby loading the motor system and preventing mimicry. Each participant's responses were modeled by fitting psychometric functions. Sensitivity to changes in smile sincerity and bias were inferred from the slope and the point of subjective equality (PSE), respectively. Motor interference significantly decreased sensitivity relative to baseline, but did systematically affect bias. Experiment 3 examined whether the motor manipulation has similar effects on judgments of facial gender, a task equated for difficulty but which is not thought to recruit motor processes. Neither slope nor PSE estimates for gender judgments were affected, indicating that the loss of sensitivity seen in Experiment 2 is relatively specific to judgments of expression and does not reflect generic distraction. These findings accord with the view that judgments of facial expression benefit from motor contributions to perception. Meeting abstract presented at VSS 2015. PMID:26327064

  14. Reducing the temperature sensitivity of SOI waveguide-based biosensors

    Science.gov (United States)

    Gylfason, Kristinn B.; Mola Romero, Albert; Sohlström, Hans

    2012-06-01

    Label-free photonic biosensors fabricated on silicon-on-insulator (SOI) can provide compact size, high evanescent field strength at the silicon waveguide surface, and volume fabrication potential. However, due to the large thermo optic coefficient of water-based biosamples, the sensors are temperature-sensitive. Consequently, active temperature control is usually used. However, for low cost applications, active temperature control is often not feasible. Here, we use the opposite polarity of the thermo-optic coefficients of silicon and water to demonstrate a photonic slot waveguide with a distribution of power between sample and silicon that aims to give athermal operation in water. Based on simulations, we made three waveguide designs close to the athermal point, and asymmetric integrated Mach- Zehnder interferometers for their characterization. The devices were fabricated on SOI with a 220 nm device layer and 2 ?m buried oxide, by electron beam lithography of hydrogen silsesquioxane (HSQ) resist, and etching in a Cl2/HBr/O2/He plasma. With Cargile 50350 fused silica matching oil as top cladding, the group index of the three guides varies from 1.9 to 2.8 at 1550 nm. The temperature sensitivity of the devices varied from -70 to -160 pm/K under the same conditions. A temperature sensitivity of -2 pm/K is projected with water as top cladding.

  15. Water use efficiency by coffee arabica after glyphosate application / Eficiência do uso da água pelo cafeeiro arábica após aplicação de glyphosate

    Scientific Electronic Library Online (English)

    Felipe Paolinelli de, Carvalho; André Cabral, França; Bruna Pereira de, Souza; Cíntia Maria Teixeira, Fialho; José Barbosa dos, Santos; Antonio Alberto da, Silva.

    2014-09-01

    Full Text Available Muitos cafeicultores utilizam o glyphosate em aplicações dirigidas. Nessas aplicações são constatados intoxicações. Através do efeito negativo direto na fotossíntese, ou indiretamente, reduzindo da taxa metabólica da planta, acredita-se que possam influenciar a eficiência do uso da água. Objetivou-s [...] e no trabalho averiguar as variáveis relacionadas ao uso da água entre cultivares de café submetidos a aplicação de subdoses de glyphosate e os efeitos de cada dose. O experimento foi conduzido em casa de vegetação utilizando-se três cultivares de cafeeiro (Coffea arabica): Acaiá (MG-6851), Catucaí Amarelo (2 SL) e Topázio (MG-1190) e, três subdoses do glyphosate (0,0; 115,2 e 460,8 g ha-1 do equivalente ácido), em esquema fatorial 3 x 3. Aos 15 DAA observou-se redução da condutância estomática. Constatou-se menor taxa de transpiração e eficiência do uso da água na quarta folha aos 15 dias após a aplicação. 45 dias após aplicação ocorreu queda da transpiração, sendo que, o Acaiá apresentou redução com aplicação de 115,2 g ha-1. O glyphosate reduziu a eficiência do uso da água, apresentando efeitos transitórios, mas que podem causar atraso no crescimento e produção do cafeeiro. O cultivar Acaiá foi o mais tolerante ao glyphosate, não alterando sua eficiência do uso da água com aplicação do herbicida. Abstract in english Many coffee growers apply glyphosate in directed applications, but some phytotoxicity has been noted. It is believed some herbicides can exert a direct or indirect negative effect on photosynthesis by reducing the metabolic rate in a way that can affect the water use efficiency. The objective of thi [...] s study was to investigate the variables related to water use among coffee cultivars subjected to the application of glyphosate and the effects of each dose. The experiment was conducted in a greenhouse using three varieties of coffee (Coffea arabica), Acaiá (MG-6851), Catucaí Amarelo (2SL) and Topázio (MG-1190), and three doses of glyphosate (0.0, 115.2 and 460.8 g acid equivalent ha-1), in a factorial 3 x 3 design. At 15 days after application, a reduction in stomatal conductance was observed, and smaller transpiration rate and water use efficiency were found in the fourth leaf at 15 days after application. There was a decrease in the transpiration rate at 45 DAA, with the Acaiá cultivar showing reductions with 115.2 g ha-1. There was transitory reduction in water use efficiency with glyphosate application, but can affect the growth and production. The Acaiá cultivar showed the highest tolerance to glyphosate because the water use efficiency after herbicide application.

  16. Glyphosate-Resistant Goosegrass from Mississippi

    OpenAIRE

    Vijay K. Nandula; Wright, Alice A.; William T. Molin

    2013-01-01

    A suspected glyphosate-resistant goosegrass [Eleusine indica (L.) Gaertn.] population, found in Washington County, Mississippi, was studied to determine the level of resistance and whether the resistance was due to a point mutation, as was previously identified in a Malaysian population. Whole plant dose response assays indicated a two- to four-fold increase in resistance to glyphosate. Leaf disc bioassays based on a glyphosate-dependent increase in shikimate levels indicated a five- to eight...

  17. ADSORPTION OF GLYPHOSATE AND AMPAIN AGRICULTURAL SOILS

    OpenAIRE

    Nicola Rampazzo; Gorana Rampazzo Todorovic; Axel Mentler

    2013-01-01

    Immediately after application glyphosate is mostly adsorbed in the upper 2 cm of soils, and is then transported and adsorbed after few days in deeper soil horizons with concomitant increasing content of its metabolite aminomethylphosphonic acid (AMPA). This work confirmed previous studies, where Fe-oxides seem to play a major role in the adsorption of glyphosate and AMPA in soils:  the Chernozem featured lower contents of Fed and Feo, with consequently lower adsorption of glyphosate and AMPAa...

  18. Control of glyphosate resistant hairy fleabane (Conyza bonariensis) with dicamba and 2,4-D / Controle de buva (Conyza bonariensis) resistente ao glyphosate com dicamba e 2,4-D

    Scientific Electronic Library Online (English)

    D.J., Soares; W.S., Oliveira; R.F., López-Ovejero; P.J, Christoffoleti.

    2012-06-01

    Full Text Available Os herbicidas mimetizadores de auxinas como dicamba e 2,4-D são alternativas para o controle de buva resistente ao glyphosate. Com a possível futura liberação comercial de culturas resistentes ao dicamba e 2,4-D, a aplicação destes herbicidas reguladores de crescimento será uma provável alternativa [...] de controle de buva resistente ao glyphosate. O objetivo desta pesquisa foi modelar por meio de curvas de dose-resposta a eficácia do dicamba e 2,4-D isolados e dicamba em associação com glyphosate para controle de uma população de buva resistente. Um estudo de doseresposta em casa de vegetação foi conduzido em delineamento experimental inteiramente casualizado, sendo que as doses utilizadas para a construção das curvas de dose-resposta foram de 0, 120, 240, 480, 720 e 960 g i.a. ha-1de para o dicamba e o 2,4-D isolados e dicamba associado com 540 g e.a. ha-1 de glyphosate. As doses utilizadas para o glyphosate isolado foram de 0, 180, 360, 540, 720 e 960 g e.a. ha-1. Os tratamentos herbicidas foram aplicados quando asplantas estavam no estádio vegetativo de 10 a 12 folhas e altura entre 12 e 15 cm. A buva apresentou baixa sensibilidade ao glyphosate, pois não foi controlada mesmo na dose de 960 g e.a. ha-1 de glyphosate. O dicamba e o 2,4-D foram eficazes no controle da população de buva estudada. A buva responde de forma diferenciada ao 2,4-D e dicamba e será importante determinaras doses apropriadas de cada herbicida para controle de buva resistente ao glyphosate em condições de campo. A associação de glyphosate e dicamba não foi antagônica no controle da buva e o glyphosate pode causar um efeito aditivo no controle, apesar da resistência da população. Abstract in english Auxyn type herbicides such as dicamba and 2,4-D are alternative herbicides that can be used to control glyphosate-resistant hairy fleabane. With the forthcoming possibility of releasing dicamba-resistant and 2,4-D-resistant crops, use of these growth regulator herbicides will likely be an alternativ [...] e that can be applied to the control of glyphosate resistant hairy fleabane (Conyza bonariensis). The objective of this research was to model the efficacy, through dose-response curves, of glyphosate, 2,4-D, isolated dicamba and glyphosatedicamba combinations to control a brazilian hairy fleabane population resistant to glyphosate. The greenhouse dose-response studies were conducted as a completely randomized experimental design, and the rates used for dose response curve construction were 0, 120, 240, 480, 720 and 960 g a.i. ha-1 for 2,4-D, dicamba and the dicamba combination, with glyphosate at 540 g a.e. ha-1. The rates for glyphosate alone were 0, 180, 360, 540, 720 and 960 g a.e. ha-1. Herbicides were applied when the plants were in a vegetative stage with 10 to 12 leaves and height between 12 and 15 cm. Hairy fleabane had low sensitivity to glyphosate, with poor control even at the 960 g a.e. ha-1 rate. Dicamba and 2,4-D were effective in controlling the studied hairy fleabane. Hairy fleabane responds differently to 2,4-D and dicamba. The combination of glyphosate and dicamba was not antagonistic to hairy fleabane control, and glyphosate may cause an additive effect on the control, despite the population resistance.

  19. Control of glyphosate resistant hairy fleabane (Conyza bonariensis with dicamba and 2,4-D Controle de buva (Conyza bonariensis resistente ao glyphosate com dicamba e 2,4-D

    Directory of Open Access Journals (Sweden)

    D.J. Soares

    2012-06-01

    Full Text Available Auxyn type herbicides such as dicamba and 2,4-D are alternative herbicides that can be used to control glyphosate-resistant hairy fleabane. With the forthcoming possibility of releasing dicamba-resistant and 2,4-D-resistant crops, use of these growth regulator herbicides will likely be an alternative that can be applied to the control of glyphosate resistant hairy fleabane (Conyza bonariensis. The objective of this research was to model the efficacy, through dose-response curves, of glyphosate, 2,4-D, isolated dicamba and glyphosatedicamba combinations to control a brazilian hairy fleabane population resistant to glyphosate. The greenhouse dose-response studies were conducted as a completely randomized experimental design, and the rates used for dose response curve construction were 0, 120, 240, 480, 720 and 960 g a.i. ha-1 for 2,4-D, dicamba and the dicamba combination, with glyphosate at 540 g a.e. ha-1. The rates for glyphosate alone were 0, 180, 360, 540, 720 and 960 g a.e. ha-1. Herbicides were applied when the plants were in a vegetative stage with 10 to 12 leaves and height between 12 and 15 cm. Hairy fleabane had low sensitivity to glyphosate, with poor control even at the 960 g a.e. ha-1 rate. Dicamba and 2,4-D were effective in controlling the studied hairy fleabane. Hairy fleabane responds differently to 2,4-D and dicamba. The combination of glyphosate and dicamba was not antagonistic to hairy fleabane control, and glyphosate may cause an additive effect on the control, despite the population resistance.Os herbicidas mimetizadores de auxinas como dicamba e 2,4-D são alternativas para o controle de buva resistente ao glyphosate. Com a possível futura liberação comercial de culturas resistentes ao dicamba e 2,4-D, a aplicação destes herbicidas reguladores de crescimento será uma provável alternativa de controle de buva resistente ao glyphosate. O objetivo desta pesquisa foi modelar por meio de curvas de dose-resposta a eficácia do dicamba e 2,4-D isolados e dicamba em associação com glyphosate para controle de uma população de buva resistente. Um estudo de doseresposta em casa de vegetação foi conduzido em delineamento experimental inteiramente casualizado, sendo que as doses utilizadas para a construção das curvas de dose-resposta foram de 0, 120, 240, 480, 720 e 960 g i.a. ha-1de para o dicamba e o 2,4-D isolados e dicamba associado com 540 g e.a. ha-1 de glyphosate. As doses utilizadas para o glyphosate isolado foram de 0, 180, 360, 540, 720 e 960 g e.a. ha-1. Os tratamentos herbicidas foram aplicados quando asplantas estavam no estádio vegetativo de 10 a 12 folhas e altura entre 12 e 15 cm. A buva apresentou baixa sensibilidade ao glyphosate, pois não foi controlada mesmo na dose de 960 g e.a. ha-1 de glyphosate. O dicamba e o 2,4-D foram eficazes no controle da população de buva estudada. A buva responde de forma diferenciada ao 2,4-D e dicamba e será importante determinaras doses apropriadas de cada herbicida para controle de buva resistente ao glyphosate em condições de campo. A associação de glyphosate e dicamba não foi antagônica no controle da buva e o glyphosate pode causar um efeito aditivo no controle, apesar da resistência da população.

  20. Residual herbicides in weed management for glyphosate-resistant soybean in Brazil / Herbicidas residuais em manejo de plantas daninhas na soja resistente ao glyphosate no Brasil

    Scientific Electronic Library Online (English)

    R.F., Lopes Ovejero; D.J., Soares; W.S., Oliveira; L.B., Fonseca; G.U., Berger; J.K., Soteres; P.J., Christoffoleti.

    2013-12-01

    Full Text Available Em sistemas de produção agrícola onde a cultura da soja tolerante ao glyphosate (Glycine max) está inserida e onde não há a prática de rotação de culturas com herbicidas alternativos, o uso exclusivo e contínuo do glyphosate tem levado ao surgimento de populações de plantas daninhas resistentes, que [...] podem limitar ou comprometer os benefícios dessa tecnologia. Nesse sentido, a eficiência de programas de manejo que envolvem herbicidas residuais (sulfentrazone, flumioxazin, imazethapyr, diclosulam, chlorimuron e s-metolachlor) aplicados na pré-emergência seguidos de glyphosate na pós-emergência da cultura (PRE-POST) foi comparada à de programas com apenas glyphosate na pós-emergência ? POST. O estudo constituiu-se de nove experimentos realizados durante as safras agrícolas 2009/2010 e 2010/2011. Os programas PRE-POST foram eficientes no controle de Amaranthus viridis, Brachiaria plantaginea, Bidens pilosa, Commelina benghalensis, Eleusine indica, Euphorbia heterophylla e Raphanus raphanistrum, sendo semelhantes aos níveis de controle do programa com duas aplicações de glyphosate POST. Alguns programas PRE-POST não foram eficientes para Cenchrus echinatus, Ipomoea hederifolia e Ipomoea triloba. Sulfentrazone e diclosulam PRE-POST melhoraram o controle de Ipomoea triloba em relação às aplicações sequenciais de glyphosate. Quanto à produtividade, não foram observadas diferenças significativas entre os tratamentos herbicidas. As aplicações de herbicidas residuais em pré-emergência seguidos da aplicação de glyphosate em pós-emergência resultam em controles consistentes de plantas daninhas e evitam a competição inicial. Além disso, estes programas utilizam pelo menos dois modos de ação que contribuem para a diversidade do uso de herbicidas que será necessária para ficar à frente de novos casos de resistência, independentemente de quando as plantas daninhas possam aparecer. Abstract in english In agricultural production systems where the glyphosate-resistant soybean crop (Glycine max) is grown and the practice of crop rotation with alternative herbicides is not adopted, the exclusive and continuous use of glyphosate has led to the occurrence of resistant weed populations that may limit or [...] compromise the benefits of this technology. Thus, the efficacy of weed management programs, including the use of residual herbicides (sulfentrazone, flumioxazin, imazethapyr, diclosulan, chlorimuron and s-metolachlor) applied in preemergence and followed by in-crop postemergence applications of glyphosate (PRE-POST) were compared to glyphosate postemergence only programs - POST. The study was conducted across nine locations during the 2009/2010 and 2010/2011 growing seasons. PRE-POST programs were efficient in the control of Amaranthus viridis, Brachiaria plantaginea, Bidens pilosa, Commelina benghalensis, Eleusine indica, Euphorbia heterophylla and Raphanus raphanistrum, with the level of control being similar when comparing the program with two applications of glyphosate POST. Some PRE-POST programs were not efficient in controlling Cenchrus echinatus, Ipomoea hederifolia and Ipomoea triloba. Sulfentrazone and diclosulam PRE-POST programs improved the control of Ipomoea triloba compared to sequential applications of glyphosate alone. No significant differences in soybean yield were observed between any of the herbicide treatments or study locations. The use of residual herbicides in preemergence followed by glyphosate in-crop postemergence provides consistent weed control and reducing early season weed competition. Furthermore, these programs utilize at least two herbicide modes of action for herbicide use diversity, which will be needed to stay ahead of resistance build-up, regardless of when weeds may appear.

  1. Rosiglitazone Reduces Blood Pressure in Female Dahl Salt-sensitive Rats

    OpenAIRE

    Sartori-Valinotti, Julio C.; Venegas-Pont, Marcia R.; LaMarca, Babbette B.; Romero, Damian G.; Yanes, Licy L.; Racusen, Lorraine C.; Jones, Allison V.; Ryan, Michael J.; Reckelhoff, Jane F.

    2009-01-01

    Postmenopausal women (PMW) are at greater risk for salt-sensitive hypertension and insulin resistance than premenopausal women. Peroxisome proliferator activated receptor-gamma (PPAR?) agonists reduce blood pressure (BP) and insulin resistance in humans. As in PMW, ovariectomy (OVX) increases salt sensitivity of BP and body weight in Dahl salt sensitive (DS) rats. This study addressed whether rosiglitazone (ROSI), a PPAR? agonist, attenuates salt-sensitive hypertension in intact (INT) and OVX...

  2. Glyphosate-Degrading Microorganisms from Industrial Activated Sludge

    OpenAIRE

    Balthazor, Terry M.; Hallas, Laurence E.

    1986-01-01

    A plating medium was developed to isolate N-phosphonomethylglycine (glyphosate)-degrading microorganisms, with glyphosate as the sole phosphorus source. Two industrial biosystems treating glyphosate wastes contained elevated microbial counts on the medium. One purified isolate metabolized glyphosate to aminomethylphosphonic acid, mineralizing this accumulating intermediate during log growth. This microorganism has been identified as a Flavobacterium species.

  3. Análisis de la sensibilidad de biotipos de Lolium multiflorum a herbicidas inhibidores de la enzima ALS, ACCasa y Glifosato / Sensitivity analysis of Lolium multiflorum biotypes to Glyphosate, ACCase and ALS-inhibiting herbicides

    Scientific Electronic Library Online (English)

    P., Diez De Ulzurrun; M.I., Leaden.

    2012-09-01

    Full Text Available A pesar de los avances logrados en el control de las malezas con el uso de herbicidas, el manejo de las mismas no se simplificó, sino que, al contrario, surgieron nuevos desafíos, como la aparición de resistencia a herbicidas. En 2007, se reportó en Lolium multiflorum el segundo caso de resistencia [...] a glifosato detectado en Argentina. En el sudeste de la provincia de Buenos Aires se registraron fallas de control a campo en poblaciones de Lolium multiflorum debido a su resistencia a distintos herbicidas de las familias de los inhibidores de ALS y de ACCasa y al herbicida glifosato. El objetivo de este estudio fue caracterizar el nivel de resistencia a ciertos herbicidas inhibidores de la ALS y de la ACCasa y al glifosato en una población de L. multiflorum de Lobería (Bs As, Argentina) supuestamente resistente (LmR). Se realizaron bioensayos en cajas de Petri y se determinó la GR50 mediante la variación en la longitud de coleoptile. Las curvas de dosis-respuesta se obtuvieron por medio de la ecuación log-logística. El biotipo LmR presentó resistencia múltiple a herbicidas con tres modos de acción diferentes: glifosato, inhibidores de ALS y de ACCasa. Dicho ensayo demostró la aparición de un biotipo de L. multiflorum con resistencia a múltiples principios activos. Abstract in english Despite progress in weed control using herbicides, management has not been simplified, but new challenges such as herbicides resistance have arisen. In 2007, a Lolium multiflorum population resistant to glyphosate was reported, as the second case of glyphosate resistant weeds in Argentina. In the so [...] utheast of Buenos Aires province, control failures in populations of L. multiflorum to different families of herbicide such as ALS and ACCase inhibitors and to glyphosate at field level have been registered. The aim of this study was to characterize the level of resistance to certain herbicides inhibitors of ALS, ACCase and glyphosate in a putatively resistant (LmR) population of L. multiflorum of Loberia (Buenos Aires, Argentina). Bioassays were conducted in Petri dishes and the GR50 was determined by the length of coleoptile. Curves dose-response were obtained using the log-logistic equation. The LmR biotype survived under multiple herbicides of three different modes of action, glyphosate, ALS and ACCase inhibitors. This test showed the appearance of a biotype of L. multiflorum with resistance to multiple active ingredients.

  4. Análisis de la sensibilidad de biotipos de Lolium multiflorum a herbicidas inhibidores de la enzima ALS, ACCasa y Glifosato Sensitivity analysis of Lolium multiflorum biotypes to Glyphosate, ACCase and ALS-inhibiting herbicides

    Directory of Open Access Journals (Sweden)

    P. Diez De Ulzurrun

    2012-09-01

    Full Text Available A pesar de los avances logrados en el control de las malezas con el uso de herbicidas, el manejo de las mismas no se simplificó, sino que, al contrario, surgieron nuevos desafíos, como la aparición de resistencia a herbicidas. En 2007, se reportó en Lolium multiflorum el segundo caso de resistencia a glifosato detectado en Argentina. En el sudeste de la provincia de Buenos Aires se registraron fallas de control a campo en poblaciones de Lolium multiflorum debido a su resistencia a distintos herbicidas de las familias de los inhibidores de ALS y de ACCasa y al herbicida glifosato. El objetivo de este estudio fue caracterizar el nivel de resistencia a ciertos herbicidas inhibidores de la ALS y de la ACCasa y al glifosato en una población de L. multiflorum de Lobería (Bs As, Argentina supuestamente resistente (LmR. Se realizaron bioensayos en cajas de Petri y se determinó la GR50 mediante la variación en la longitud de coleoptile. Las curvas de dosis-respuesta se obtuvieron por medio de la ecuación log-logística. El biotipo LmR presentó resistencia múltiple a herbicidas con tres modos de acción diferentes: glifosato, inhibidores de ALS y de ACCasa. Dicho ensayo demostró la aparición de un biotipo de L. multiflorum con resistencia a múltiples principios activos.Despite progress in weed control using herbicides, management has not been simplified, but new challenges such as herbicides resistance have arisen. In 2007, a Lolium multiflorum population resistant to glyphosate was reported, as the second case of glyphosate resistant weeds in Argentina. In the southeast of Buenos Aires province, control failures in populations of L. multiflorum to different families of herbicide such as ALS and ACCase inhibitors and to glyphosate at field level have been registered. The aim of this study was to characterize the level of resistance to certain herbicides inhibitors of ALS, ACCase and glyphosate in a putatively resistant (LmR population of L. multiflorum of Loberia (Buenos Aires, Argentina. Bioassays were conducted in Petri dishes and the GR50 was determined by the length of coleoptile. Curves dose-response were obtained using the log-logistic equation. The LmR biotype survived under multiple herbicides of three different modes of action, glyphosate, ALS and ACCase inhibitors. This test showed the appearance of a biotype of L. multiflorum with resistance to multiple active ingredients.

  5. Influence of glyphosate and its formulation (Roundup[reg]) on the toxicity and bioavailability of metals to Ceriodaphnia dubia

    International Nuclear Information System (INIS)

    This study examined the toxicological interaction between glyphosate (or its formulation, Roundup[reg]) and several heavy metals to a freshwater cladoceran, Ceriodaphnia dubia. We demonstrated that all binary combinations of Roundup[reg] and metals (Cd, Cu, Cr, Ni, Pb, Se and Zn) exhibited 'less than additive' mixture toxicity, with 48-h LC50 toxic unit>1. Addition of glyphosate alone could significantly reduce the acute toxicity of Ag, Cd, Cr, Cu, Ni, Pb and Zn (but not Hg and Se). The ratio between glyphosate and metal ions was important in determining the mitigation of metal toxicity by glyphosate. A bioaccumulation study showed that in the presence of glyphosate the uptake of some metals (e.g. Ag) was halted but that of others (e.g. Hg) was increased significantly. Therefore, our study strongly suggests that glyphosate and its commercial formulations can control the toxicity as well as the bioavailability of heavy metals in aquatic ecosystems where both groups of chemicals can co-occur. - Glyphosate can control the toxicity and bioavailability of many heavy metals in the aquatic environment

  6. Suscetibilidade de duas Gramas-boiadeiras a diferentes formulações de glyphosate / Susceptibility of Cutgrass and Peruvian Watergrass to different glyphosate formulations

    Scientific Electronic Library Online (English)

    Ananda, Scherner; Luis Antonio de, Avila; Fábio, Schreiber; Nelson Diehl, Kruse; Dirceu, Agostinetto; Jesus Juares Oliveira, Pinto; Rodrigo Ribeiro, Pestana.

    2014-03-01

    Full Text Available A utilização do herbicida glyphosate para o controle químico das espécies de gramas-boiadeiras nas lavouras orizícolas não tem se mostrado eficiente. Nesse contexto, a investigação do controle dessas espécies com o glyphosate torna-se de fundamental importância, uma vez que não estão disponíveis no [...] mercado herbicidas seletivos para o controle dessas em pós-emergência na cultura do arroz irrigado. Em vista do exposto, o objetivo do presente estudo foi avaliar a suscetibilidade das gramas-boiadeiras a diferentes formulações de glyphosate. Foram conduzidos dois experimentos em casa de vegetação em esquema fatorial. No primeiro experimento, o fator A constituiu-se de duas formulações de glyphosate (sal potássico e isopropilamina) e o fator B de nove doses dos herbicidas (zero; 175; 350; 700; 1400; 2800; 5600; 11200; 22400g e.a. ha-1). No segundo experimento, o fator A constituiu-se de duas espécies de gramas-boiadeiras (Leersia hexandra e Luziola peruviana), o fator B de três formulações do glyphosate (sal amônio, potássico e isopropilamina) e o fator C de nove doses dos herbicidas (zero; 87,5; 175; 350; 700; 1400; 2800; 5600; 11200g e.a. ha-1). Com base nos resultados obtidos, foi possível observar que as espécies apresentaram diferença de suscetibilidade ao herbicida glyphosate. Além disso, Leersia hexandra foi mais sensível em comparação a Luziola peruviana. As formulações de glyphosate influenciaram na suscetibilidade das espécies ao controle, sendo que, Roundup Transorb R® e Roundup Ultra® proporcionam melhor controle das espécies de gramas-boiadeiras. Abstract in english The use of glyphosate to chemical control of Cutgrass and Peruvian Watergrass with the use of non-selective herbicides has not been efficient. In this context, the investigation of chemical control of these species to glyphosate is very important, since there are not available commercially selective [...] herbicides to control these species in post-emergence of irrigated rice. Therefore, the objective of this study was to evaluate the susceptibility of Cutgrass and Peruvian Watergrass to different formulations of glyphosate. Two factorial experiments were conducted in a greenhouse, in the first the A factor were two formulations of glyhposate (potassium and isopropylamine salt) and the B factor were nine doses of the herbicide (zero; 175; 350; 700; 1400; 2800; 5600; 11200; 22400g a.e. ha-1). In the second experiment, the A factor were two species (Leersia hexandra and Luziola peruviana), the B factor were three formulations of glyphosate (amoniun, potassium e isopropylamine salt) and the C factor were nine doses of herbicides (zero; 87,5; 175; 350; 700; 1400; 2800; 5600; 11200g a.e. ha-1). Based on the results obtained, it was observed that these species exhibit differential susceptibility to glyphosate. Moreover, Leersia hexandra was more sensitive when compared to Luziola peruviana. Glyphosate formulation influenced control efficiency, where Transorb Roundup R® and Roundup Ultra® provided the best control of the two species.

  7. 78 FR 60707 - Glyphosate; Pesticide Tolerances

    Science.gov (United States)

    2013-10-02

    ...code 112). Food manufacturing...glyphosate to the genetically modified ``Optimum GLY...Determination of Safety Section 408(b...residue in or on a food) only if EPA...an international food safety standards-setting...of glyphosate to genetically modified ``Optimum...

  8. 76 FR 27268 - Glyphosate; Pesticide Tolerance

    Science.gov (United States)

    2011-05-11

    ... with glyphosate follows. In the Federal Register of April 8, 2011 (76 FR 19701) (FRL-8866- 8), EPA... estimated aggregate risks resulting from use of glyphosate, as discussed in the April 8, 2011 (76 FR 19701...) 305-5805. II. Summary of Petitioned-For Tolerance In the Federal Register of February 4, 2011 (76...

  9. Glyphosate-resistant goosegrass from Mississippi

    Science.gov (United States)

    A glyphosate resistant population of goosegrass (Eleusine indica (L.) Gaertn.) was documented near Stoneville, Mississippi, USA, in an area which had received multiple applications of glyphosate each year for the previous eleven years. Resistance ratios based on dose response growth reduction assays...

  10. 76 FR 27268 - Glyphosate; Pesticide Tolerance

    Science.gov (United States)

    2011-05-11

    ...World Health Organization food standards program, and it is recognized as an international food safety standards-setting...N-acetyl glyphosate is found in genetically modified (GMO) glyphosate-resistant...any pesticide residues in food. The Agency understands the...that the pesticide meets the safety standard imposed by...

  11. Gene amplification confers glyphosate resistance in Amaranthus palmeri

    OpenAIRE

    Gaines, Todd A; Zhang, Wenli; Wang, Dafu; Bukun, Bekir; Chisholm, Stephen T.; Shaner, Dale L.; Nissen, Scott J; Patzoldt, William L.; Tranel, Patrick J.; Culpepper, A. Stanley; Grey, Timothy L.; Webster, Theodore M.; Vencill, William K.; Sammons, R Douglas; Jiang, Jiming

    2009-01-01

    The herbicide glyphosate became widely used in the United States and other parts of the world after the commercialization of glyphosate-resistant crops. These crops have constitutive overexpression of a glyphosate-insensitive form of the herbicide target site gene, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Increased use of glyphosate over multiple years imposes selective genetic pressure on weed populations. We investigated recently discovered glyphosate-resistant Amaranthus palmer...

  12. Associação de glyphosate e imidazolinonas no controle de arroz-vermelho em arroz Clearfield® / Association of glyphosate and imidazolinones on red rice control in Clearfield™ rice

    Scientific Electronic Library Online (English)

    Valmir Gaedke, Menezes; Carlos Henrique Paim, Mariot; Augusto, Kalsing; Thais Fernanda Stella de, Freitas; Daniel Santos, Grohs; Felipe de Oliveira, Matzenbacher.

    2013-12-01

    Full Text Available O objetivo do presente trabalho foi o de avaliar os efeitos da utilização de glyphosate e herbicidas imidazolinonas, em aplicações isoladas ou associadas, sobre o controle de arroz-vermelho (Oryza sativa) e produtividade de grãos de arroz Clearfield®. O experimento foi conduzido a campo na safra 200 [...] 7/08, em Cachoeirinha, RS, Brasil, com delineamento em blocos ao acaso e tratamentos dispostos em arranjo fatorial (2x6), usando-se quatro repetições. O fator A constou de dois níveis do herbicida glyphosate, aplicados no subperíodo semeadura-emergência da cultura por ocasião do início da emissão do coleóptilo do arroz (ponto de agulha); o fator B constou de seis tratamentos com imazethapyr+imazapic, aplicados em associação ao glyphosate ou quando a cultura atingiu o estádio de três folhas expandidas. As três variáveis explicativas analisadas foram a população de plantas de arroz e arroz-vermelho, a eficácia do controle de arroz-vermelho e a produtividade de grãos da cultura. O uso de glyphosate no ponto de agulha reduziu em 75% a população do arroz-vermelho e aumentou em 40% a produtividade de grãos de arroz, em relação à testemunha. O uso isolado de herbicidas imidazolinonas e sua associação com o dessecante proporcionou controle eficaz do arroz-vermelho e incrementou a produtividade de grãos, em comparação à situação sem controle da infestante, independente da dose e do sistema de aplicação. Abstract in english The objective of this research was to evaluate the effects of the utilization of glyphosate and imidazolinones herbicides, in isolated or associated applications, on the effectiveness of red rice (Oryza sativa) control and grain yield of Clearfield-rice. The experiment was conducted under field cond [...] itions in 2007/08, in Cachoeirinha, RS, Brazil, using a randomized block design in a two-factorial design 2x6, with four replicates. The factor A was composed by two levels of glyphosate, applied during the subperiod between sowing and crop emergence at the early coleoptile stage of the rice plants; and the factor B consisted of six treatments with imazethapyr+imazapic, applied in association with glyphosate or when the rice crop plants had three expanded leaves. The crop and weed populations, red rice control and grain yield of crop were evaluated. The results show that the glyphosate application at the early coleoptile stage of the crop reduced 75% the red rice population and increased 40% the grain yield, in relation to the situation without weed control. The use of imidazolinones and their association with glyphosate provided effective control of red rice and increased the grain yield, independent of rates and application system.

  13. Glyphosate influence on the physiological parameters of Conyza bonariensis biotypes / Influência de glyphosate em parâmetros fisiológicos de biótipos de Conyza bonariensis

    Scientific Electronic Library Online (English)

    L., Vargas; D.R.O., Silva; D., Agostinetto; M.B., Matallo; F.M., Santos; S.D.B., Almeida; G., Chavarria; D.F.P., Silva.

    2014-03-01

    Full Text Available Objetivou-se neste trabalho determinar alterações na fotossíntese e na inibição da EPSPs, com base no acúmulo de ácido chiquímico, em biótipos de buva resistente e suscetível ao glyphosate. Foram realizados dois experimentos, conduzidos em esquema bifatorial. No primeiro, avaliaram-se biótipos de bu [...] va (um resistente e outro suscetível ao glyphosate) e doses do herbicida (0 e 1.080ge.a.ha-1) aplicadas sobre a planta daninha. No segundo experimento, os biótipos de buva (resistente e suscetível ao glyphosate) foram avaliados em cinco épocas: 0, 3, 7, 10 e 14 dias após a aplicação do herbicida (DAH). Foram efetuadas determinações da taxa fotossintética, transpiração, eficiência da carboxilação e uso eficiente da água, empregando analisador de gases no infravermelho (IRGA), e a concentração de ácido chiquímico, determinada por HPLC. A aplicação do glyphosate afetou negativamente os parâmetros fotossintéticos do biótipo suscetível, causando total inibição da taxa fotossintética, da taxa transpiratória, da eficiência da carboxilação e da eficiência do uso da água, a partir dos 7DAH. Já para o biótipo resistente, não se observou total inibição dos parâmetros fotossintéticos. Em ambos os biótipos ocorreu acúmulo de ácido chiquímico após aplicação de glyphosate; contudo, o biótipo suscetível apresentou as maiores concentrações, indicando maior sensibilidade da enzima EPSPs. O acúmulo de ácido chiquímico no biótipo resistente indica que o mecanismo de resistência não está relacionado somente com a insensibilidade da EPSPs ao glyphosate e/ou que outros mecanismos de resistência podem estar envolvidos. Abstract in english The objective of this study was to determine changes in gas exchange and inhibition of EPSPs, based on the accumulation of shikimic acid in horseweed biotypes resistant and sensitive to glyphosate. Two experiments were conducted in a factorial model. The first one evaluated horseweed biotypes (one r [...] esistant and one susceptible to glyphosate), and herbicide rates (0 and 1,080 g a.e. ha ¹) applied on the weed. In the second experiment, the horseweed biotypes (susceptible and resistant to glyphosate) were evaluated in five periods as following: 0, 3, 7, 10, and 14 days after herbicide application (DAH). The photosynthetic rate, transpiration, carboxylation efficiency, and water efficiency were determined using an infrared gas analyzer (IRGA), and shikimic acid concentration by HPLC. The application of glyphosate damaged the photosynthetic parameters of the susceptible biotype, causing complete inhibition of the photosynthetic rate, transpiration rate, carboxylation efficiency and water use efficiency, starting from the 7 DAH. On the other hand, total inhibition of the photosynthetic parameters was not observed for the resistant biotype. Shikimic acid accumulation occurred in both biotypes after glyphosate application but the susceptible biotype had the highest concentrations, indicating greater sensitivity of the enzyme EPSPs. The accumulation of shikimic acid in the resistant biotype indicates that the mechanism of resistance is not related to the total insensitivity of the enzyme EPSPs to glyphosate and/or that other resistance mechanisms may be involved.

  14. The use of environmental metabolomics to determine glyphosate level of exposure in rapeseed (Brassica napus L.) seedlings

    International Nuclear Information System (INIS)

    Metabolic profiling in plants can be used to differentiate between treatments and to search for biomarkers for exposure. A methodology for processing Ultra-High-Performance Liquid Chromatography-Diode-Array-Detection data is devised. This methodology includes a scheme for selecting informative wavelengths, baseline removal, retention time alignment, selection of relevant retention times, and principal component analysis (PCA). Plant crude extracts from rapeseed seedling exposed to sublethal concentrations of glyphosate are used as a study case. Through this approach, plants exposed to concentrations down to 5 ?M could be distinguished from the controls. The compounds responsible for this differentiation were partially identified and were different from those specific for high exposure samples, which suggests that two different responses to glyphosate are elicited in rapeseed depending on the level of exposure. The PCA loadings indicate that a combination of other metabolites could be more sensitive than the response of shikimate to detect glyphosate exposure. - Highlights: ? A method for processing UHPLC-DAD data for plant metabolic profiling is devised. ? The metabolic profiling approach is more sensitive to glyphosate exposure than shikimate. ? Plants exposed to concentrations down to 5 ?M can be distinguished from the controls. ? Two different responses to glyphosate may be elicited in rapeseed depending on the level of exposure. - A novel untargeted environmental metabololomic approach is used to detect low-level glyphosate exposure of rapeseed seedlings.

  15. The use of environmental metabolomics to determine glyphosate level of exposure in rapeseed (Brassica napus L.) seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Petersen, Iben Lykke; Tomasi, Giorgio; Sorensen, Hilmer; Boll, Esther S.; Hansen, Hans Christian Bruun [Department of Basic Sciences and Environment, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C (Denmark); Christensen, Jan H., E-mail: jch@life.ku.dk [Department of Basic Sciences and Environment, Faculty of Life Sciences, University of Copenhagen, Thorvaldsensvej 40, DK-1871 Frederiksberg C (Denmark)

    2011-10-15

    Metabolic profiling in plants can be used to differentiate between treatments and to search for biomarkers for exposure. A methodology for processing Ultra-High-Performance Liquid Chromatography-Diode-Array-Detection data is devised. This methodology includes a scheme for selecting informative wavelengths, baseline removal, retention time alignment, selection of relevant retention times, and principal component analysis (PCA). Plant crude extracts from rapeseed seedling exposed to sublethal concentrations of glyphosate are used as a study case. Through this approach, plants exposed to concentrations down to 5 {mu}M could be distinguished from the controls. The compounds responsible for this differentiation were partially identified and were different from those specific for high exposure samples, which suggests that two different responses to glyphosate are elicited in rapeseed depending on the level of exposure. The PCA loadings indicate that a combination of other metabolites could be more sensitive than the response of shikimate to detect glyphosate exposure. - Highlights: > A method for processing UHPLC-DAD data for plant metabolic profiling is devised. > The metabolic profiling approach is more sensitive to glyphosate exposure than shikimate. > Plants exposed to concentrations down to 5 {mu}M can be distinguished from the controls. > Two different responses to glyphosate may be elicited in rapeseed depending on the level of exposure. - A novel untargeted environmental metabololomic approach is used to detect low-level glyphosate exposure of rapeseed seedlings.

  16. Ion implantation reduces radiation sensitivity of metal oxide silicon /MOS/ devices

    Science.gov (United States)

    1971-01-01

    Implanting nitrogen ions improves hardening of silicon oxides 30 percent to 60 percent against ionizing radiation effects. Process reduces sensitivity, but retains stability normally shown by interfaces between silicon and thermally grown oxides.

  17. Herbicidas alternativos para controle de biótipos de Conyza bonariensis e C. canadensis resistentes ao glyphosate / Alternative herbicides to control glyphosate-resistant biotypes of Conyza bonariensis and C. canadensis

    Scientific Electronic Library Online (English)

    M.S., Moreira; M.S.C., Melo; S.J.P., Carvalho; M., Nicolai; P.J., Crhistoffoleti.

    Full Text Available Após sucessivos anos, aplicações do herbicida glyphosate em pomares de citros no Estado de São Paulo selecionaram biótipos resistentes de Conyza bonariensis e C. canadensis. Na ocorrência de plantas daninhas resistentes em uma área agrícola, tornam-se necessárias mudanças nas práticas de manejo para [...] obtenção de adequado controle das populações resistentes, bem como para a redução da pressão de seleção sobre outras espécies. Assim, este trabalho foi realizado com o objetivo de identificar herbicidas alternativos para controle de biótipos de Conyza spp. resistentes ao herbicida glyphosate, com aplicações em diferentes estádios fenológicos da planta daninha. Três experimentos foram conduzidos em campo, em pomares de citros em formação, sobre plantas de buva em estádio fenológico de dez folhas e no pré-florescimento. Para plantas no estádio de dez folhas, controle satisfatório foi obtido com aplicações de glyphosate + bromacil + diuron (1.440 + 1.200 + 1.200 g ha-1), glyphosate + atrazina (1.440 + 1.500 g ha-1) e glyphosate + diuron (1.440 + 1.500 g ha-1). Quando em estádio de pré-florescimento de Conyza spp., a aplicação do herbicida amônio-glufosinato, na dose de 400 g ha-1, isolado ou associado a MSMA, bromacil+diuron, metsulfuron, carfentrazone e paraquat, foi a alternativa viável para controle dos biótipos resistentes ao glyphosate. Abstract in english After successive years, glyphosate applications on São Paulo-Brazil citrus orchards selected resistant biotypes of Conyza bonariensis and C. canadensis. The occurrence of herbicide-resistant weed biotypes at some agricultural area makes it necessary to change the management practices to reach effect [...] ive control of the selected resistant populations, as well as to reduce selection pressure on the other species. Thus, this work aimed to identify the alternative herbicides to control glyphosate-resistant biotypes of Conyza spp., with applications at different weed phenological stages. Three trials were developed under field conditions: in citrus orchards under formation, in plants with phenological stages of ten leaves and at pre-flowering. For plants at the ten leaf stage, satisfactory control was reached with applications of glyphosate + bromacil + diuron (1,440 + 1,200 + 1,200 g ha-1), glyphosate + atrazine (1,440 + 1,500 g ha-1) and glyphosate + diuron (1,440 + 1,500 g ha-1). For Conyza spp. plants at the pre-flowering stage, ammonium-glufosinate application, at the rate of 400 g ha-1, isolated or associated to MSMA, bromacil+diuron, metsulfuron, carfentrazone and paraquat, was a viable alternative to control glyphosate-resistant biotypes.

  18. A red and far-red light receptor mutation confers resistance to the herbicide glyphosate

    KAUST Repository

    Sharkhuu, Altanbadralt

    2014-06-01

    Glyphosate is a widely applied broad-spectrum systemic herbicide that inhibits competitively the penultimate enzyme 5-enolpyruvylshikimate 3-phosphate synthase (EPSPS) from the shikimate pathway, thereby causing deleterious effects. A glyphosate-resistant Arabidopsis mutant (gre1) was isolated and genetic analyses indicated that a dysfunctional red (R) and far-red (FR) light receptor, phytochrome B (phyB), caused this phenotype. This finding is consistent with increased glyphosate sensitivity and glyphosate-induced shikimate accumulation in low R:FR light, and the induction of genes encoding enzymes of the shikimate pathway in high R:FR light. Expression of the shikimate pathway genes exhibited diurnal oscillation and this oscillation was altered in the phyB mutant. Furthermore, transcript analysis suggested that this diurnal oscillation was not only dependent on phyB but was also due to circadian regulatory mechanisms. Our data offer an explanation of the well documented observation that glyphosate treatment at various times throughout the day, with their specific composition of light quality and intensity, results in different efficiencies of the herbicide.

  19. Interação de glyphosate com carfentrazone-ethyl / Glyphosate - carfentrazone-ethyl interaction

    Scientific Electronic Library Online (English)

    R.C., Werlang; A.A., Silva.

    2002-04-01

    Full Text Available Foi conduzido um experimento em condições controladas para determinar a interação do carfentrazone-ethyl em mistura no tanque com o herbicida glyphosate, no controle de seis espécies de plantas daninhas. Glyphosate aplicado isoladamente na dose de 720 g ha-1 foi eficaz no controle de Amaranthus hybr [...] idus (100%), Desmodium tortuosum (100%), Bidens pilosa (99%), Eleusine indica (96%), Digitaria horizontalis (100%) e Commelina benghalensis (93%) aos 21 DAA. Carfentrazone-ethyl aplicado isoladamente controlou eficazmente C. benghalensis. As misturas de glyphosate nas doses de 252 e 720 g ha-1 com carfentrazone-ethyl nas doses de 15 e 30 g ha¹ demonstraram efeito aditivo no controle de A. hybridus, D. tortuosum e Bidens pilosa, à exceção das misturas de glyphosate na dose de 252 g ha-1 com as doses de 15 e 30 g ha-1 de carfentrazone-ethyl, que proporcionam efeito sinergístico no controle de D. tortuosum. A adição das duas doses de carfentrazone-ethyl antagonizou o efeito de glyphosate na menor dose (252 g ha-1) no controle de E. indica, apresentando, no entanto, efeito aditivo com o glyphosate na maior dose (720 g ha-1). Já para D. horizontalis, as misturas de carfentrazone-ethyl com glyphosate na menor dose (252 g ha-1) apresentaram efeito sinergístico no controle dessa espécie, demonstrando, ainda, efeito aditivo na mistura com glyphosate na dose de 720 g ha-1. A mistura de carfentrazone-ethyl com glyphosate proporcionou efeito aditivo no controle de C. benghalensis, independentemente das combinações de doses avaliadas. Os resultados deste experimento indicam que carfentrazone-ethyl apresenta comportamento diferenciado quanto à interação com glyphosate, dependendo da espécie de planta daninha e da dose dos herbicidas utilizados na mistura em tanque, sendo complementar na mistura em tanque com glyphosate, pois demonstrou efeito antagônico em poucas das combinações estudadas, prevalecendo seu efeito aditivo na mistura com glyphosate, no controle das espécies avaliadas. Abstract in english Under evironmental controlled conditions experiments were conducted to determine the efficacy of carfentrazone-ethyl in tank mixture with glyphosate to control six weed species. Glyphosate alone at 720 g ha-1 was effective in controlling Amaranthus hybridus (100%), Desmodium tortuosum (100%), Bidens [...] pilosa (99%), Eleusine indica (96%), Digitaria horizontalis (100%) and Commelina benghalensis (93%) at 21 DAA. Carfentrazone-ethyl alone controlled only C. benghalensis. efficiently. Glyphosate mixtures (252 and 720 g ha-1) with carfentrazone-ethyl at 15 and 30 g ha¹ showed an additive effect in controlling A. hybridus, D. tortuosum and Bidens pilosa, except for glyphosate mixture at 252 g ha-1 with carfentrazone-ethyl at 15 and 30 g ha-1, which showed synergism in controlling D. tortuosum. The addition of the two carfentrazone-ethyl doses antagonized the effect of the smallest dose (252 g ha-1) of glyphosate on E. indica control. However, the largest glyphosate dose (720 g ha-1) provided additive effect when mixed with both carfentrazone-ethyl doses. For D. horizontalis, carfentrazone-ethyl mixtures with glyphosate in the smallest dose (252 g ha-1) had a synergistic effect in the control of this species, also showing and additive effect in the mixture with glyphosate at 720 g ha-1. Carfentrazone-ethyl mixture with glyphosate provided an additive effect in C. benghalensis control, regardless of dose combinations. The results of this experiment indicate that carfentrazone-ethyl presents a differentiated behavior when interacting with glyphosate, depending on the weed species and the herbicide dose used in the tank mixtures, being complementary in tank-mix combinations with glyphosate, since it showed an antagonistic effect in few combinations, with its additive effect prevailing in the mixture with glyphosate for the control of the evaluated species.

  20. Interação de glyphosate com carfentrazone-ethyl Glyphosate - carfentrazone-ethyl interaction

    Directory of Open Access Journals (Sweden)

    R.C. Werlang

    2002-04-01

    Full Text Available Foi conduzido um experimento em condições controladas para determinar a interação do carfentrazone-ethyl em mistura no tanque com o herbicida glyphosate, no controle de seis espécies de plantas daninhas. Glyphosate aplicado isoladamente na dose de 720 g ha-1 foi eficaz no controle de Amaranthus hybridus (100%, Desmodium tortuosum (100%, Bidens pilosa (99%, Eleusine indica (96%, Digitaria horizontalis (100% e Commelina benghalensis (93% aos 21 DAA. Carfentrazone-ethyl aplicado isoladamente controlou eficazmente C. benghalensis. As misturas de glyphosate nas doses de 252 e 720 g ha-1 com carfentrazone-ethyl nas doses de 15 e 30 g ha¹ demonstraram efeito aditivo no controle de A. hybridus, D. tortuosum e Bidens pilosa, à exceção das misturas de glyphosate na dose de 252 g ha-1 com as doses de 15 e 30 g ha-1 de carfentrazone-ethyl, que proporcionam efeito sinergístico no controle de D. tortuosum. A adição das duas doses de carfentrazone-ethyl antagonizou o efeito de glyphosate na menor dose (252 g ha-1 no controle de E. indica, apresentando, no entanto, efeito aditivo com o glyphosate na maior dose (720 g ha-1. Já para D. horizontalis, as misturas de carfentrazone-ethyl com glyphosate na menor dose (252 g ha-1 apresentaram efeito sinergístico no controle dessa espécie, demonstrando, ainda, efeito aditivo na mistura com glyphosate na dose de 720 g ha-1. A mistura de carfentrazone-ethyl com glyphosate proporcionou efeito aditivo no controle de C. benghalensis, independentemente das combinações de doses avaliadas. Os resultados deste experimento indicam que carfentrazone-ethyl apresenta comportamento diferenciado quanto à interação com glyphosate, dependendo da espécie de planta daninha e da dose dos herbicidas utilizados na mistura em tanque, sendo complementar na mistura em tanque com glyphosate, pois demonstrou efeito antagônico em poucas das combinações estudadas, prevalecendo seu efeito aditivo na mistura com glyphosate, no controle das espécies avaliadas.Under evironmental controlled conditions experiments were conducted to determine the efficacy of carfentrazone-ethyl in tank mixture with glyphosate to control six weed species. Glyphosate alone at 720 g ha-1 was effective in controlling Amaranthus hybridus (100%, Desmodium tortuosum (100%, Bidens pilosa (99%, Eleusine indica (96%, Digitaria horizontalis (100% and Commelina benghalensis (93% at 21 DAA. Carfentrazone-ethyl alone controlled only C. benghalensis. efficiently. Glyphosate mixtures (252 and 720 g ha-1 with carfentrazone-ethyl at 15 and 30 g ha¹ showed an additive effect in controlling A. hybridus, D. tortuosum and Bidens pilosa, except for glyphosate mixture at 252 g ha-1 with carfentrazone-ethyl at 15 and 30 g ha-1, which showed synergism in controlling D. tortuosum. The addition of the two carfentrazone-ethyl doses antagonized the effect of the smallest dose (252 g ha-1 of glyphosate on E. indica control. However, the largest glyphosate dose (720 g ha-1 provided additive effect when mixed with both carfentrazone-ethyl doses. For D. horizontalis, carfentrazone-ethyl mixtures with glyphosate in the smallest dose (252 g ha-1 had a synergistic effect in the control of this species, also showing and additive effect in the mixture with glyphosate at 720 g ha-1. Carfentrazone-ethyl mixture with glyphosate provided an additive effect in C. benghalensis control, regardless of dose combinations. The results of this experiment indicate that carfentrazone-ethyl presents a differentiated behavior when interacting with glyphosate, depending on the weed species and the herbicide dose used in the tank mixtures, being complementary in tank-mix combinations with glyphosate, since it showed an antagonistic effect in few combinations, with its additive effect prevailing in the mixture with glyphosate for the control of the evaluated species.

  1. Identificação de biótipos de azevém (Lolium multiflorum resistentes ao herbicida glyphosate em pomares de maçã Identification of glyphosate-resistant ryegrass (Lolium multiflorum biotypes in apple orchards

    Directory of Open Access Journals (Sweden)

    L. Vargas

    2004-12-01

    Full Text Available O glyphosate é um herbicida de amplo espectro utilizado há mais de 15 anos em pomares de maçã na região de Vacaria-RS, para manejo da vegetação nas linhas da cultura. São realizadas, em geral, três a quatro aplicações por ciclo e a dose normalmente utilizada é de 720 a 1.080 g e.a. ha-1 de glyphosate (2 a 3 L ha-1 do produto comercial. O azevém (Lolium multiflorum é uma planta daninha comum em pomares e, tradicionalmente, sensível ao glyphosate. Entretanto, nos últimos anos a ocorrência de plantas de azevém que, após receberem o tratamento com glyphosate, não manifestam sintomas significativos de toxicidade sugere que elas adquiriram resistência ao produto. Assim, com o objetivo de avaliar a resposta de uma população de plantas de azevém ao glyphosate, foram realizados três experimentos: um em campo e dois em casa de vegetação. No experimento em campo os tratamentos avaliados constaram de doses crescentes de glyphosate (0, 360, 720, 1.440, 2.880, 5.760 e 11.520 g e.a. ha-1, e os herbicidas paraquat, glufosinate, haloxyfop e diclofop foram empregados como produtos-padrão, aplicados em dois estádios vegetativos do azevém. No experimento em casa de vegetação, os tratamentos constaram de doses crescentes de glyphosate (0, 360, 720, 1.440, 2.880 e 5.760 g e.a. ha-1 mais os herbicidas testemunhas, aplicados sobre plantas do biótipo considerado resistente e de um sensível. No segundo experimento realizado em casa de vegetação foram avaliados tratamentos contendo glyphosate (720, 1.440, 2.880, 720 + 720 e 720 + 1.440 g e.a. ha-1, em aplicações únicas e seqüenciais, mais os herbicidas paraquat, glufosinate, haloxyfop, clethodim, sethoxydim, diclofop, fenoxaprop, fluazifop, paraquat + diuron, atrazine + simazine, trifluralin e metolachlor. A toxicidade dos tratamentos herbicidas foi avaliada aos 15, 30 e 45 DAT (dias após tratamento. Os resultados obtidos nos experimentos em campo e em casa de vegetação, de forma geral, evidenciam que o biótipo sensível é facilmente controlado com o herbicida glyphosate e pelos demais herbicidas pós-emergentes avaliados, independentemente do estádio vegetativo. Demonstram, ainda, que o biótipo resistente apresenta-se, igualmente ao biótipo sensível, altamente suscetível aos herbicidas com mecanismo de ação distinto daquele do glyphosate. No entanto, o biótipo resistente apresenta baixa resposta ao herbicida glyphosate, mesmo se este for empregado em altas doses, evidenciando ter adquirido resistência a esse produto.Glyphosate is a wide spectrum herbicide used for over 15 years in apple orchards in Vacaria-RS for weed control in rows of trees. Usually, 3 to 4 applications per year are made at a rate of 720 to 1080 g a.e. glyphosate ha-1 (2 to 3 L ha-1 of commercial product. Ryegrass (Lolium multiflorum is a common weed in orchards and traditionally sensitive to glyphosate. However, in the last years, some ryegrass plants have not been found to show significant toxicity symptoms after treatment with glyphosate, suggesting that they acquired resistance to this product. To evaluate the response of a ryegrass plant population to glyphosate, one field and two greenhouse experiments were carried out. The field experiment treatments had increasing rates of glyphosate (0; 360; 720; 1,440; 2,880; 5,760 and 11,520 g a.e. ha-1, in addition to the herbicides paraquat, glufosinate-ammonium, haloxyfop and diclofop-methyl as standards, sprayed at two different vegetative growth stages of ryegrass. The greenhouse experiments had increasing rates of glyphosate (0; 360; 720; 1,440; 2,880 and 5,760 g a.e. ha-1 plus the above listed check herbicides sprayed on biotypes considered resistant and on plants of one susceptible biotype. In the second greenhouse experiment, glyphosate rates (720; 1,440; 2,880; 720 + 720 and 720 + 1,440 g a.e. ha-1 were sprayed in single and sequential applications, in addition to the herbicides paraquat, glufosinate-ammonium, haloxyfop, clethodim, sethoxydim, diclofop-methyl, fenoxaprop, fluazifop, paraquat + diuron,

  2. Sugarcane tolerance to ratoon eradication with glyphosate determined by physiological responses / Tolerância da soqueira da cana-de-açúcar à erradicação com glyphosate determinada por respostas fisiológicas

    Scientific Electronic Library Online (English)

    M.A., Silva; M.T., Arantes; R., Oliver; M.C., Brunelli.

    2014-03-01

    Full Text Available O presente trabalho teve como objetivo avaliar a tolerância de cultivares de cana-de-açúcar à erradicação de soqueiras com diferentes doses de glyphosate por meio de respostas fisiológicas. Para isso, um ensaio foi desenvolvido no delineamento experimental de blocos ao acaso em esquema fatorial 4 x [...] 4 (cultivares x doses), totalizando 16 tratamentos com quatro repetições. Foram utilizados os cultivares IAC91-5155, IACSP93-3046, IAC86-2480 e IAC87-3396 tratados com as doses de glyphosate 0, 1.920, 2.400, e 2.880gha-1. As variáveis analisadas foram porcentagem de perfilhos mortos, eficiência quântica do FSII (Fv/Fm) e índice SPAD. Há diferenças entre cultivares de cana-de-açúcar quanto à eliminação de perfilhos e a respostas fisiológicas a diferentes doses de glyphosate. A dose de 2.880gha-1 foi a mais eficiente em eliminar perfilhos de cana-de-açúcar. Os cultivares IAC86-2480, IAC87-3396 e IACSP93-3046 foram os mais sensíveis, e o IAC91-5155 tolerou por mais tempo os danos promovidos no aparato fotossintético à dessecação das soqueiras pelo glyphosate. Devido às respostas diferenciadas, manejos distintos devem ser considerados para a eliminação das soqueiras de diferentes cultivares. Abstract in english This study aimed to evaluate the tolerance of sugarcane cultivars to ratoon eradication under different glyphosate rates by means of physiological responses. Therefore, a trial was carried out in randomized complete blocks with 4 x 4 factorial design (cultivars x rates) totaling 16 treatments with f [...] our replicates. The cultivars IAC91-5155, IACSP93-3046, and IAC86-2480 and IAC87-3396 and the glyphosate rates 0 g ha-1; 1,920 g ha-1; 2,400 g ha-1; 2,880 g ha-1 were tested. The variables analyzed were percentage of tiller mortality, quantum efficiency of PSII (Fv/Fm) and SPAD index. The results showed that there are differences among sugarcane cultivars for tiller eradication and for physiological responses with glyphosate different rates. The rate of 2,880 g ha-1 was the most efficient in eliminating sugarcane tillers. The cultivars IAC86-2480, IAC87-3396 and IACSP93-3046 were the most sensitive and the IAC91-5155 tolerated, for a longer period of time, the damage to the photosynthetic apparatus of the ratoons caused by glyphosate desiccation. Due to different responses, different managements should be considered for eliminating ratoons of different cultivars.

  3. The toxicity of glyphosate alone and glyphosate-surfactant mixtures to western toad (Anaxyrus boreas) tadpoles.

    Science.gov (United States)

    Vincent, Kim; Davidson, Carlos

    2015-12-01

    Pesticide choice based on toxicity to nontarget wildlife is reliant on available toxicity data. Despite a number of recent studies examining the effects of glyphosate on amphibians, very few have aimed to understand the toxicological effects of glyphosate in combination with surfactants as it is commonly applied in the field. Land managers interested in making pesticide choices based on minimizing impacts to nontarget wildlife are hindered by a lack of published toxicity data. Short-term acute toxicity trials were conducted for glyphosate in the form of isopropylamine salt (IPA) alone and mixed with 2 surfactants: Agri-dex and Competitor with western toad (Anaxyrus [Bufo] boreas) tadpoles. Glyphosate IPA mixed with Competitor was 6 times more toxic than glyphosate IPA mixed with Agri-dex, and both mixtures were more toxic than glyphosate IPA alone. The median lethal concentrations reported for 24-h and 48-h exposures were 8279?mg/L (24?h) and 6392?mg/L (48?h) for glyphosate IPA alone; 5092?mg/L (24?h) and 4254?mg/L (48?h) for glyphosate IPA mixed with Agri-dex; and 853?mg/L (24?h) and 711?mg/L (48?h) for glyphosate IPA mixed with Competitor. The present study indicates that the toxicity of a tank mix may be greatly increased by the addition of surfactants and may vary widely depending on the specific surfactant. Environ Toxicol Chem 2015;34:2791-2795. © 2015 SETAC. PMID:26084619

  4. Monitoring glyphosate and AMPA concentrations in wells and drains using the sorbicell passive sampler

    DEFF Research Database (Denmark)

    Vendelboe, Anders Lindblad; de Jonge, Hubert

    Glyphosate is one of the world’s most extensively used weed control agents. Glyphosate, and its metabolite aminomethylphosphonic acid (AMPA), are suspected to be hazardous to human health and the aquatic environment. In Denmark, the extensive use has resulted in an increasing number of occurrences in groundwater wells and tile drains, stressing the need for extensive monitoring of this compound in the environment. Traditionally, monitoring programs are based on grab sampling which is time consuming and expensive due to the need for frequent sampling events. Using a passive sampling device, the SorbiCell, will decrease the workload and number of samples freeing up funds for larger monitoring programs. When installed in a well the SorbiCell will continuously sample the water giving either a flux-weighed or time-weighted average measurement of the glyphosate/AMPA concentration throughout the sampling period. It may therefore be possible to measure lower concentrations as the glyphosate/AMPA sorbed in the SorbiCell is an accumulated measurement. Also, glyphosate/AMPA associated with sudden flush events will be detected by the SorbiCells, while such events may pass between two consecutive grab samples. To document the ability of the SorbiCell to capture glyphosate/AMPA, a series of laboratory flow experiments were carried out. Sorption and release from the flow cells is tested with two influent solutions (0.15 µg/l and 5 µg/l), one of demineralized water and the other with drain water from the Silstrup site (part of the Danish Pesticide Leaching Assessment Program, PLAP), spiked with 14C marked glyphosate. Two different volumes of effluent were then eluted through Sorbicell’s with two different capacities. The concentration of glyphosate/AMPA was continuously measured in both the influent and effluent. The aim of the study is to test and verify if the glyphosate/AMPA sensitive SorbiCell is an efficient and reliable, and cost-effective technology for groundwater and drainwater monitoring of pesticides.

  5. Associações entre o herbicida glyphosate e inseticidas na cultura da soja Roundup Ready® / Associations among glyphosate and insecticides in Roundup Ready® soybean

    Scientific Electronic Library Online (English)

    F.A., Petter; S.O., Procópio; A., Cargnelutti Filho; A.L.L., Barroso; L.P., Pacheco; A.F., Bueno.

    Full Text Available Este trabalho teve o objetivo de avaliar os efeitos da associação do herbicida glyphosate com 10 inseticidas de diferentes grupos químicos sobre a cultura da soja Roundup Ready® (cultivar Monsoy 8585 RR®), o controle de plantas daninhas e o controle da lagarta-da-soja (Anticarsia gemmatalis). O expe [...] rimento foi realizado em lavoura no município de Nova Xavantina - MT, no período de novembro de 2005 a abril de 2006, em solo classificado como Latossolo Vermelho distrófico. O delineamento experimental utilizado foi o de blocos ao acaso, em esquema fatorial 11 x 2, sendo os fatores constituídos por 11 tratamentos inseticidas [lambdacyhalothrin (3,75 g ha-1); permethrin (12,50 g ha-1); methamidophos (300,00 g ha-1); chlorpyriphos (240,00 g ha-1); acephate (150,00 g ha-1); endosulfan (175,00 g ha-1); methomyl (107,50 g ha-1); lufenuron (7,50 g ha-1); triflumuron (14,40 g ha-1); spinosad (24,00 g ha-1); e testemunha sem inseticida], com ou sem a adição (mistura em tanque) de 960 g e.a. ha-1 de glyphosate, formando 22 tratamentos, conduzidos em quatro repetições. Os tratamentos foram aplicados 30 dias depois da emergência da cultura. A mistura do herbicida glyphosate com o inseticida chlorpyriphos causou fitotoxicidade inicial à cultura da soja RR®. O controle das plantas daninhas Chamaesyce hirta, Alternanthera tenella, Euphorbia heterophylla e Cenchrus echinatus não foi afetado pelas misturas de glyphosate com todos os inseticidas avaliados. A adição do glyphosate à calda de aplicação prejudicou a eficiência inicial dos inseticidas methomyl, methamidophos, chlorpyriphos e acephate no controle de Anticarsia gemmatalis, porém incrementou o controle dessa praga quando associado aos inseticidas spinosad, lambdacyhalothrin e lufenuron. A combinação de glyphosate com os inseticidas methamidophos, chlorpyriphos, lufenuron, triflumuron e spinosad proporcionou os maiores níveis de produtividade de grãos da soja RR®. Abstract in english This research aimed to evaluate the effects of the association of the herbicide glyphosate with 10 different insecticides of several chemical groups on Roundup Ready® soybean (Monsoy 8585 RR®), weeds, and on velvetbean caterpillar (Anticarsia gemmatalis). The experiment was carried out under field c [...] onditions at Nova Xavantina-MT, from November 2005 to April 2006 in soil classified as Dystrophic Red Latosol. Trial design was a factorial randomized complete block having 11 insecticide treatments: [lambdacyhalothrin (3,75 g ha-1); permethrin (12,50 g ha-1); methamidophos (300,00 g ha-1); chlorpyriphos (240,00 g ha-1); acephate (150,00 g ha-1); endosulfan (175,00 g ha-1); methomyl (107,50 g ha-1); lufenuron (7,50 g ha-1); triflumuron (14,40 g ha-1); spinosad (24,00 g ha-1); and untreated without insecticide] with and without addiction (tank mixture) of 960 g a.e. ha-1 of glyphosate, totalling 22 treatments. Each treatment had four replications. Treatments were applied 30 days after soybean emergence. Tank mixture of glyphosate and insecticide caused phytotoxicity to soybean. The control of the weeds Chamaesyce hirta, Alternathera tenella, Euphorbia heterophylla and Cenchrus echinatus was not affected by the glyphosate mixture. Tank mixture of glyphosate with the insecticides methomyl, methamidophos, chlorpyriphos and acephate reduced their control of Anticarsia gemmatalis. However, the control performance of the insecticides spinosad, lambdacyhalothrin and lufenuron was increased. The combination of glyphosate with the insecticides methamidophos, chlorpyriphos, lufenuron, triflumuron and spinosad provided the highest soybean yields.

  6. Adjoint design sensitivity analysis of reduced atomic systems using generalized Langevin equation for lattice structures

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min-Geun; Jang, Hong-Lae [National Creative Research Initiatives Center for Isogeometric Optimal Design and Department of Naval Architecture and Ocean Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744 (Korea, Republic of); Cho, Seonho, E-mail: secho@snu.ac.kr [National Creative Research Initiatives Center for Isogeometric Optimal Design and Department of Naval Architecture and Ocean Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-744 (Korea, Republic of)

    2013-05-01

    An efficient adjoint design sensitivity analysis method is developed for reduced atomic systems. A reduced atomic system and the adjoint system are constructed in a locally confined region, utilizing generalized Langevin equation (GLE) for periodic lattice structures. Due to the translational symmetry of lattice structures, the size of time history kernel function that accounts for the boundary effects of the reduced atomic systems could be reduced to a single atom’s degrees of freedom. For the problems of highly nonlinear design variables, the finite difference method is impractical for its inefficiency and inaccuracy. However, the adjoint method is very efficient regardless of the number of design variables since one additional time integration is required for the adjoint GLE. Through numerical examples, the derived adjoint sensitivity turns out to be accurate and efficient through the comparison with finite difference sensitivity.

  7. Influence of glyphosate on the copper dissolution in phosphate buffer

    Science.gov (United States)

    Coutinho, C. F. B.; Silva, M. O.; Machado, S. A. S.; Mazo, L. H.

    2007-01-01

    The electrochemical behavior of copper microelectrode in phosphate buffer in the presence of glyphosate was investigated by electrochemical techniques. It was observed that the additions of glyphosate in the phosphate buffer increased the anodic current of copper microelectrode and the electrochemical dissolution was observed. This phenomenon could be associated with the Cu(II) complexation by glyphosate forming a soluble complex. Physical characterization of the surface showed that, in absence of glyphosate, an insoluble layer covered the copper surface; on the other hand, in presence of glyphosate, it was observed a corroded copper surface with the formation of glyphosate complex in solution.

  8. Suppression of reduced sensitivity of eddy current testing depending on defect orientation

    International Nuclear Information System (INIS)

    Stress corrosion cracking (SCC) is generated on material structures in nuclear power plants. An eddy current testing (ECT) is used as a method for inspection techniques of a SCC. However when the eddy current direction is in parallel with defect direction, sensitivity of our ECT drops drown to one-quarter than a perpendicular direction. In order to prevent from this reduced sensitivity, Invert Exciting Method was developed. Adjacent exciter coils, which are located in two lines, are alternately opposite in phase of current. Therefore adjacent eddy currents, which are formed in the surface of metallic specimens, are also alternately opposite in phased of current. Then these eddy currents interfere with each other. Consequently eddy currents are inclined to scan direction. Using inclined eddy currents, the ECT has equal detection sensitivity for both defects parallel and perpendicular to scan direction. On the other hand, sensitivity drops down for defects in the same direction to inclined eddy currents. Then we added the function to inverse the phase for exciter coils in a set of line to the ECT system. Hereby the ECT can form symmetrical inclined eddy currents and prevent from reduced sensitivity. We applied Invert Exciting Method to the ECT system and conducted defect detection tests. As a result, we confirmed that detection sensitivity for both parallel and perpendicular defects are equal and Invert Exciting Method is effective in suppression of reduced sensitivity of the ECT depending on defect orientation. (author)

  9. Detection of the onset of glyphosate-induced soybean plant injury through chlorophyll fluorescence signal extraction and measurement

    Science.gov (United States)

    Zhao, Feng; Guo, Yiqing; Huang, Yanbo; Reddy, Krishna N.; Zhao, Yanhua; Molin, William T.

    2015-01-01

    In this study, chlorophyll fluorescence (ChlF) was used to detect the onset of soybean plant injury from treatment of glyphosate, the most widely used herbicide. Thirty-six pots of nonglyphosate-resistant soybean were randomly divided into three groups and treated with different doses of glyphosate solutions. The three treatment groups were control (CTRL) group (with no glyphosate treatment), 0.25X group (treated with 0.217 kg.ae/ha solution of glyphosate), and 0.5X group (treated with 0.433 kg.ae/ha solution of glyphosate). Three kinds of fluorescence measurements, steady-state fluorescence spectra, Kautsky effect parameters, and ChlF-related spectral indices were extracted and generated from the measurements in the glyphosate treatment experiment. The mean values of these fluorescence measurements for each of the CTRL group, the 0.25X group, and the 0.5X group were calculated. Glyphosate-induced leaf injury was then analyzed by examining the separability of these mean values at 6, 24, 48, and 72 hours after the treatment (HAT). Results indicate that the peak position of far-red ChlF shows an obvious blue shift for glyphosate-treated soybean, and peak values of steady-state fluorescence spectra for the three groups can be significantly distinguished from each other at 48 HAT and later. Four Kautsky effect parameters, Fv, Fv/Fm, Area, and PI, are parameters sensitive to glyphosate treatment, showing some differences between the CTRL group and treated groups at 24 HAT, and significant differences among the three groups at and beyond 48 HAT. Moreover, ChlF-related spectral indices, R6832/(R675.R690) and R690/R655, are also shown to be useful in detection of the glyphosate injury, though they are less effective than the steady-state fluorescence spectra and the Kautsky effect parameters. Based on the presented results, it can be concluded that glyphosate-induced soybean injury can be detected in a timely manner by the ChlF measurements, and this method has the potential to be further developed into practical use.

  10. Glyphosate as a tool to produce shikimic acid in plants / Glyphosate como ferramenta para produzir ácido chiquímico em plantas

    Scientific Electronic Library Online (English)

    M.B., Matallo; S.D.B., Almeida; D.A.S., Franco; A.L., Cerdeira; D.L.P., Gazzeiro.

    2014-09-01

    Full Text Available O fosfato de oseltamivir, ingrediente ativo do antiviral Tamiflu®, é um potente inibidor viral produzido a partir do ácido chiquímico e extraído da semente de Ilicium verum, sua mais importante fonte natural. Tendo como sítio de ação a enzima 5 enolpiruvilchiquimato-3-fosfato sintase (EPSPs), o glyp [...] hosate é o único composto capaz de inibir a sua atividade, com o consequente acúmulo do ácido chiquímico nas plantas. Plantas de milho e soja foram pulverizadas com subdoses de glyphosate (0,0 a 230,4 ge.a.ha-1), determinando-se o teor de ácido chiquímico na massa seca dessas plantas por HPLC aos 3,7 e 10 dias após aplicação. Os resultados mostraram acúmulo de ácido chiquímico na massa seca dessas plantas, com aumento de até 969% no milho e 33.000% na soja, com picos de concentração aos 3 DAT. A praticabilidade industrial do processo de obtenção do ácido chiquímico, aliada às condições edafoclimáticas favoráveis ao plantio de milho e soja em diversos países, favorece o uso de subdoses de glyphosate na biossíntese de ácido chiquímico, com potencial para ser explorado como indutor na produção do fosfato de oseltamivir com baixo impacto ambiental. Abstract in english Oseltamivir phosphate is a potent viral inhibitor produced from shikimic acid extracted from seeds of Ilicium verum, the most important natural source. With the site of action 5-enolpyruvylshikimate-3-phosphate synthase (EPSP), glyphosate is the only compound capable of inhibiting its activity with [...] the consequent accumulation of shikimic acid in plants. Corn and soybean plants were sprayed with reduced rates of glyphosate (0.0 to 230.4 g a.i. ha¹) and shikimic acid content in the dry mass was determined by HPLC 3, 7 and 10 days after application. Results showed shikimic acid accumulation in dry mass with increases of up to 969% in corn and 33,000% on soybeans, with peak concentrations 3 days after treatment (DAT). Industrial feasibility for shikimic acid production, combined with favorable climatic conditions for growing corn and soybean in virtually all over Brazil, favor the use of reduced rates of glyphosate in shikimic acid biosynthesis, with potential for use as an inducer in exploration of alternative sources for production of oseltamivir phosphate with low environmental impact.

  11. Impact of phosphate on glyphosate uptake and toxicity in willow.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; Le Manac'h, Sarah Gingras; Moingt, Matthieu; Smedbol, Elise; Paquet, Serge; Labrecque, Michel; Lucotte, Marc; Juneau, Philippe

    2016-03-01

    Phosphate (PO4(3-)) has been shown to increase glyphosate uptake by willow, a plant species known for its phytoremediation potential. However, it remains unclear if this stimulation of glyphosate uptake can result in an elevated glyphosate toxicity to plants (which could prevent the use of willows in glyphosate-remediation programs). Consequently, we studied the effects of PO4(3-) on glyphosate uptake and toxicity in a fast growing willow cultivar (Salix miyabeana SX64). Plants were grown in hydroponic solution with a combination of glyphosate (0, 0.001, 0.065 and 1mgl(-1)) and PO4(3-) (0, 200 and 400mgl(-1)). We demonstrated that PO4(3-) fertilization greatly increased glyphosate uptake by roots and its translocation to leaves, which resulted in increased shikimate concentration in leaves. In addition to its deleterious effects in photosynthesis, glyphosate induced oxidative stress through hydrogen peroxide accumulation. Although it has increased glyphosate accumulation, PO4(3-) fertilization attenuated the herbicide's deleterious effects by increasing the activity of antioxidant systems and alleviating glyphosate-induced oxidative stress. Our results indicate that in addition to the glyphosate uptake, PO4(3-) is involved in glyphosate toxicity in willow by preventing glyphosate induced oxidative stress. PMID:26561751

  12. Glyphosate surfactant herbicide poisoning and management

    OpenAIRE

    Mahendrakar, Kranthi; Venkategowda, Pradeep M.; Rao, S. Manimala; Mutkule, Dnyaneshwar. P.

    2014-01-01

    Glyphosate is a widely used herbicide in agriculture, forestry, industrial weed control and aquatic environments. Glyphosate potential as herbicide was first reported in 1971. It is a non-selective herbicide. It can cause a wide range of clinical manifestations in human beings like skin and throat irritation to hypotension, oliguria and death. We are reporting a case of a 35-year-old male patient who was admitted to our tertiary care hospital following intentional ingestion of around 200 ml o...

  13. Severe adverse effects related to dermal exposure to a glyphosate-surfactant herbicide

    DEFF Research Database (Denmark)

    Mariager, T P; Madsen, P V; Ebbehøj, N E; Schmidt, B; Juhl, A

    2013-01-01

    This is a case of severe chemical burns following prolonged accidental exposure to a glyphosate-surfactant herbicide. The patient developed local swelling, bullae and exuding wounds. Neurological impairment followed affecting finger flexion and sensation with reduced nerve conduction. Imaging revealed oedema of the soft tissue and juxta-articular osteopenia, and a causal relationship to exposure is suggested.

  14. Glyphosate-resistant Palmer Amaranth in the U.S.

    Science.gov (United States)

    Since glyphosate-resistant (GR) crops were commercialized, glyphosate has been extensively used to effectively and economically manage weeds. The adoption of GR technology also provided growers with the capabilities needed to rapidly adopt conservation tillage production systems. Selection pressure ...

  15. Expectancy of Stress-Reducing Aromatherapy Effect and Performance on a Stress-Sensitive Cognitive Task

    OpenAIRE

    Chamine, Irina; Oken, Barry S.

    2015-01-01

    Objective. Stress-reducing therapies help maintain cognitive performance during stress. Aromatherapy is popular for stress reduction, but its effectiveness and mechanism are unclear. This study examined stress-reducing effects of aromatherapy on cognitive function using the go/no-go (GNG) task performance and event related potentials (ERP) components sensitive to stress. The study also assessed the importance of expectancy in aromatherapy actions. Methods. 81 adults were randomized to 3 aroma...

  16. Enthalpic partitioning of the reduced temperature sensitivity of O2 binding in bovine hemoglobin

    DEFF Research Database (Denmark)

    Weber, Roy E; Fago, Angela; Campbell, Kevin L

    2014-01-01

    The oxygenation enthalpy of the heme groups of hemoglobin (Hb) is inherently exothermic, resulting in decreased Hb-O2 affinity with rising temperature. However, oxygenation is coupled with endothermic dissociation of allosteric effectors (e.g. protons, chloride ions and organic phosphates) from the protein moiety, which thus reduces the overall oxygenation enthalpy. The evolution of Hbs with reduced temperature sensitivity ostensibly safeguards O2 unloading in cold extremities of regionally-hete...

  17. Molecular basis of glyphosate resistance: Different approaches through protein engineering

    OpenAIRE

    Pollegioni, Loredano; Schonbrunn, Ernst; Siehl, Daniel

    2011-01-01

    Glyphosate (N-phosphonomethyl-glycine) is the most-used herbicide in the world: glyphosate-based formulations exhibit broad-spectrum herbicidal activity with minimal human and environmental toxicity. The extraordinary success of this simple small molecule is mainly due to the high specificity of glyphosate towards the plant enzyme enolpyruvylshikimate-3-phosphate synthase in the shikimate pathway leading to biosynthesis of aromatic amino acids. Starting in 1996, transgenic glyphosate-resistan...

  18. Differential response of two sourgrass populations to glyphosate

    OpenAIRE

    São Paulo State University, Jaboticabal, SP, Brazil; Bruna Pires da Silva; Paulo Roberto Fidelis Giancotti; Leonardo Bianco Carvalho; Pedro Luis da Costa Aguiar Alves

    2013-01-01

    The repetitive use of glyphosate may cause increase on the resistance of sourgrass (Digitaria insularis) through mechanisms of natural selection. The aim of this study was to verify the response of two populations of sourgrass (one collected from nonagricultural area and the other one from area suspected of glyphosate resistance) to increasing doses of glyphosate. The experimental design was completely randomized with four repetitions. For both populations, glyphosate was sprayed at 10 doses ...

  19. PHYSIOLOGY OF GLYPHOSATE-RESISTANT PALMER AMARANTH (AMARANTHUS PALMERI)

    Science.gov (United States)

    Populations of Palmer amaranth (Amaranthus palmeri) that have increased tolerance to glyphosate have been detected in Georgia. These populations are not controlled by glyphosate rates of four to ten times of that required to control glyphosate-susceptible biotypes. Laboratory studies were initiate...

  20. Response of Ranger Russet potato to simulated glyphosate drift

    Science.gov (United States)

    Field studies were conducted in 2008 at Ontario, OR, Paterson, WA, and Aberdeen, ID to determine the effect of simulated glyphosate drift on potato. Glyphosate was applied at 10-15cm height, stolon-hooking, tuber-initiation, and bulking stage. Glyphosate was applied at 0, 8.5, 54, 107, 215, and 423g...

  1. Reduced Sensitivity to Slow-Rate Dynamic Auditory Information in Children with Dyslexia

    Science.gov (United States)

    Poelmans, Hanne; Luts, Heleen; Vandermosten, Maaike; Boets, Bart; Ghesquiere, Pol; Wouters, Jan

    2011-01-01

    The etiology of developmental dyslexia remains widely debated. An appealing theory postulates that the reading and spelling problems in individuals with dyslexia originate from reduced sensitivity to slow-rate dynamic auditory cues. This low-level auditory deficit is thought to provoke a cascade of effects, including inaccurate speech perception…

  2. The effect of reduced oxygen levels on the electrostatic ignition sensitivity of dusts

    Energy Technology Data Exchange (ETDEWEB)

    Ackroyd, Graham; Bailey, Mike; Mullins, Robert [Syngenta Process Hazards Section, Huddersfield, HD2 2GZ (United Kingdom)

    2011-06-23

    When handling powders with low values of minimum ignition energy (MIE), it is often necessary to employ additional protective measures such as explosion venting, suppression, containment or inerting. Inerting generally involves reducing the oxygen concentration to around 5% v/v; however, it has been shown with gases that more modest reductions in the oxygen content can still have a significant effect on the MIE. Therefore, a test program was carried out to assess the impact of reduced oxygen levels on the MIE of a series of sensitive powders. In addition, this work was also used to investigate whether testing of such sensitive materials in the standard equipment but with reduced oxygen levels could enable the prediction of MIEs <1 mJ at standard atmospheric oxygen levels.

  3. The effect of reduced oxygen levels on the electrostatic ignition sensitivity of dusts

    International Nuclear Information System (INIS)

    When handling powders with low values of minimum ignition energy (MIE), it is often necessary to employ additional protective measures such as explosion venting, suppression, containment or inerting. Inerting generally involves reducing the oxygen concentration to around 5% v/v; however, it has been shown with gases that more modest reductions in the oxygen content can still have a significant effect on the MIE. Therefore, a test program was carried out to assess the impact of reduced oxygen levels on the MIE of a series of sensitive powders. In addition, this work was also used to investigate whether testing of such sensitive materials in the standard equipment but with reduced oxygen levels could enable the prediction of MIEs <1 mJ at standard atmospheric oxygen levels.

  4. Influence of glyphosate on Rhizoctonia crown and root rot (Rhizoctonia solani) in glyphosate-resistant sugarbeet (Beta vulgaris L.)

    Science.gov (United States)

    Previous greenhouse studies with a non-commercial glyphosate-resistant sugarbeet variety indicated that susceptibility to Rhizoctonia crown and root rot could increase after glyphosate was applied. Greenhouse and field experiments were conducted in 2008 and 2009 to determine if glyphosate influenced...

  5. Glyphosate resistant and susceptible soybean (Glycine max) and canola (Brassica napus) dose response and metabolism relationships with glyphosate

    Science.gov (United States)

    Experiments were conducted to determine 1) dose response of glyphosate-resistant (GR) and –susceptible (non-GR) soybean [Glycine max (L.) Merr.] and canola (Brassica napus L.) to glyphosate, 2) if differential metabolism of glyphosate to aminomethylphosphonic acid (AMPA) is the underlying mechanism ...

  6. Co-expression of G2-EPSPS and glyphosate acetyltransferase GAT genes conferring high tolerance to glyphosate in soybean

    Science.gov (United States)

    Guo, Bingfu; Guo, Yong; Hong, Huilong; Jin, Longguo; Zhang, Lijuan; Chang, Ru-Zhen; Lu, Wei; Lin, Min; Qiu, Li-Juan

    2015-01-01

    Glyphosate is a widely used non-selective herbicide with broad spectrum of weed control around the world. At present, most of the commercial glyphosate tolerant soybeans utilize glyphosate tolerant gene CP4-EPSPS or glyphosate acetyltransferase gene GAT separately. In this study, both glyphosate tolerant gene G2-EPSPS and glyphosate degraded gene GAT were co-transferred into soybean and transgenic plants showed high tolerance to glyphosate. Molecular analysis including PCR, Sothern blot, qRT-PCR, and Western blot revealed that target genes have been integrated into genome and expressed effectively at both mRNA and protein levels. Furthermore, the glyphosate tolerance analysis showed that no typical symptom was observed when compared with a glyphosate tolerant line HJ06-698 derived from GR1 transgenic soybean even at fourfold labeled rate of Roundup. Chlorophyll and shikimic acid content analysis of transgenic plant also revealed that these two indexes were not significantly altered after glyphosate application. These results indicated that co-expression of G2-EPSPS and GAT conferred high tolerance to the herbicide glyphosate in soybean. Therefore, combination of tolerant and degraded genes provides a new strategy for developing glyphosate tolerant transgenic crops. PMID:26528311

  7. Eficiência fotossintética e uso da água em plantas de eucalipto pulverizadas com glyphosate / Photosynthetic efficiency and water use in eucalyptus plants sprayed with glyphosate

    Scientific Electronic Library Online (English)

    A.F.L., Machado; L.R., Ferreira; L.D.T., Santos; F.A., Ferreira; R.G., Viana; M.S., Machado; F.C.L., Freitas.

    2010-06-01

    Full Text Available Objetivou-se com este trabalho avaliar a eficiência fotossintética e o uso da água por plantas de clones de eucalipto submetidas ao herbicida glyphosate. O experimento foi realizado em esquema fatorial 4 x 5, com quatro clones de eucalipto (57, 386, 1203 e 1213) e quatro doses de glyphosate (43,2; 8 [...] 6,2; 129,6; e 172,8 g ha-1) e uma testemunha sem herbicida, considerada dose zero, com quatro repetições. Aos 7, 14, 21 e 28 dias após aplicação do herbicida (DAA) foi avaliada a intoxicação das plantas, e aos 7 e 21 DAA, o fluxo de gases pelos estômatos (U - mmol s-1), a atividade fotossintética (A - mmol m-2 s-1), a condutância estomática (Gs - mol m-1 s-1), a transpiração (E - mol H2O m-2 s-1) e a eficiência do uso da água (QUE - mol CO2 mol H2O-1). Aos 50 DAA, as plantas de eucalipto foram coletadas e colocadas em estufa de ventilação forçada a 70 ºC até atingirem massa constante. Aos 21 DAA, o clone 1203 comportou-se como mais sensível ao herbicida. Não houve diferença entre clones para as variáveis fisiológicas avaliadas. Aos 21 DAA constatou-se que, com o incremento da dose de glyphosate, houve redução na condutância estomática, na taxa de fluxo de gases pelos estômatos, na taxa fotossintética e na eficiência do uso da água. Plantas dos clones 1213 e 1203 apresentaram maior acúmulo de massa seca. O aumento da dose do glyphosate promoveu menor acúmulo de massa seca das plantas de eucalipto. O glyphosate afetou negativamente o crescimento e a eficiência fotossintética e de uso da água dos clones estudados. Abstract in english The objective of this study was to assess the photosynthetic efficiency and water use by eucalyptus clones submitted to the herbicide glyphosate. The experiment was performed in a 4 x 5 factorial, with four eucalyptus clones (57, 386, 1203 and 1213), four doses of glyphosate (43.2, 86.2, 129.6 and 1 [...] 72.8 g ha-1) and a control without herbicide, considered zero dose, with four replications. At 7, 14, 21 and 28 days after herbicide application (DAA), plant intoxication was evaluated and at 7 and 21 DAA, stomatal gas flow (U - mmol s-1), photosynthetic activity (A -mmol m-2 s-1), stomatal conductance (Gs - mol m-1 s-1), transpiration (E - mol H2O m-2 s-1) and water use efficiency (WUE - mol CO2 mol H2O-1). At 50 DAA, the eucalyptus plants were collected and placed in a forced-ventilation oven at 70 °C until constant weight to determine dry mass. At 21 DAA, clone 1203 was found to be the most sensitive to the herbicide. There was no difference among the clones for the assessed physiological variables. At 21DAA, it was verified that increasing doses of glyphosate led to a reduction in stomatal conductance, stomatal gas flow rate, photosynthetic rate and water use efficiency. Plants of clones 1213 and 1203 showed a higher accumulation of dry mass. Increasing doses of glyphosate promoted less accumulation of dry mass in the eucalyptus plants. Glyphosate negatively affected growth, photosynthetic efficiency and water use of the evaluated clones.

  8. Eficiência fotossintética e uso da água em plantas de eucalipto pulverizadas com glyphosate Photosynthetic efficiency and water use in eucalyptus plants sprayed with glyphosate

    Directory of Open Access Journals (Sweden)

    A.F.L. Machado

    2010-06-01

    Full Text Available Objetivou-se com este trabalho avaliar a eficiência fotossintética e o uso da água por plantas de clones de eucalipto submetidas ao herbicida glyphosate. O experimento foi realizado em esquema fatorial 4 x 5, com quatro clones de eucalipto (57, 386, 1203 e 1213 e quatro doses de glyphosate (43,2; 86,2; 129,6; e 172,8 g ha-1 e uma testemunha sem herbicida, considerada dose zero, com quatro repetições. Aos 7, 14, 21 e 28 dias após aplicação do herbicida (DAA foi avaliada a intoxicação das plantas, e aos 7 e 21 DAA, o fluxo de gases pelos estômatos (U - mmol s-1, a atividade fotossintética (A - mmol m-2 s-1, a condutância estomática (Gs - mol m-1 s-1, a transpiração (E - mol H2O m-2 s-1 e a eficiência do uso da água (QUE - mol CO2 mol H2O-1. Aos 50 DAA, as plantas de eucalipto foram coletadas e colocadas em estufa de ventilação forçada a 70 ºC até atingirem massa constante. Aos 21 DAA, o clone 1203 comportou-se como mais sensível ao herbicida. Não houve diferença entre clones para as variáveis fisiológicas avaliadas. Aos 21 DAA constatou-se que, com o incremento da dose de glyphosate, houve redução na condutância estomática, na taxa de fluxo de gases pelos estômatos, na taxa fotossintética e na eficiência do uso da água. Plantas dos clones 1213 e 1203 apresentaram maior acúmulo de massa seca. O aumento da dose do glyphosate promoveu menor acúmulo de massa seca das plantas de eucalipto. O glyphosate afetou negativamente o crescimento e a eficiência fotossintética e de uso da água dos clones estudados.The objective of this study was to assess the photosynthetic efficiency and water use by eucalyptus clones submitted to the herbicide glyphosate. The experiment was performed in a 4 x 5 factorial, with four eucalyptus clones (57, 386, 1203 and 1213, four doses of glyphosate (43.2, 86.2, 129.6 and 172.8 g ha-1 and a control without herbicide, considered zero dose, with four replications. At 7, 14, 21 and 28 days after herbicide application (DAA, plant intoxication was evaluated and at 7 and 21 DAA, stomatal gas flow (U - mmol s-1, photosynthetic activity (A -mmol m-2 s-1, stomatal conductance (Gs - mol m-1 s-1, transpiration (E - mol H2O m-2 s-1 and water use efficiency (WUE - mol CO2 mol H2O-1. At 50 DAA, the eucalyptus plants were collected and placed in a forced-ventilation oven at 70 °C until constant weight to determine dry mass. At 21 DAA, clone 1203 was found to be the most sensitive to the herbicide. There was no difference among the clones for the assessed physiological variables. At 21DAA, it was verified that increasing doses of glyphosate led to a reduction in stomatal conductance, stomatal gas flow rate, photosynthetic rate and water use efficiency. Plants of clones 1213 and 1203 showed a higher accumulation of dry mass. Increasing doses of glyphosate promoted less accumulation of dry mass in the eucalyptus plants. Glyphosate negatively affected growth, photosynthetic efficiency and water use of the evaluated clones.

  9. Sensibilidade de estirpes de Bradyrhizobium ao glyphosate

    Directory of Open Access Journals (Sweden)

    Rodrigo Josemar Seminoti Jacques

    2010-02-01

    Full Text Available A aplicação do glyphosate sobre a soja resistente a este herbicida pode causar prejuízos à simbiose com o rizóbio. O objetivo deste trabalho foi avaliar a sensibilidade ao herbicida glyphosate de três estirpes de Bradyrhizobium recomendadas para a produção de inoculantes de sementes de soja no Brasil. Avaliou-se o efeito das concentrações de 0,0; 5,4; 10,8; 21,6 e 43,2 µg L-1 do ingrediente ativo do glyphosate [N-(fosfonometil glicina] no meio YM líquido sobre o crescimento de B. japonicum (estirpe SEMIA 5079 e de B. elkanii (estirpe SEMIA 5019 e estirpe SEMIA 587, por meio de leituras das densidades óticas e geração de curvas de crescimento. As reduções de crescimento na presença da menor concentração do glyphosate foram de 18% para SEMIA 5079, 29% para SEMIA 5019 e de 35% para SEMIA 587, sendo, de modo geral, quanto maior a concentração do herbicida no meio de cultura maior a inibição do crescimen­to. As estirpes apresentaram sensibilidade diferencial somente às concentrações mais baixas do glyphosate; nesse caso, foi possível determinar a seguinte ordem de sensibilidade: SEMIA 587 > SEMIA 5019 > SEMIA 5079. Essa sensibilidade diferencial é dependente da concentração do herbicida, pois na presença de 43,2 µg L-1 todas as estirpes tiveram seu crescimento severamente reduzido, não havendo diferença entre elas.

  10. Post-treatment with plant extracts used in Brazilian folk medicine caused a partial reversal of the antiproliferative effect of glyphosate in the Allium cepa test

    Scientific Electronic Library Online (English)

    Viviane, Dal-Souto Frescura; Andrielle, Wouters Kuhn; Haywood Dail, Laughinghouse Iv; Juçara, Terezinha Paranhos; Solange, Bosio Tedesco.

    2013-08-01

    Full Text Available Species of the genus Psychotria are used for multiple purposes in Brazilian folk medicine, either as water infusions, baths or poultices. This study was aimed to evaluate the genotoxic and antiproliferative effects of infusions of Psychotria brachypoda and P. birotula on the Allium cepa test. Exposu [...] re to distilled water was used as a negative control, while exposure to glyphosate was used as a positive control. The interaction of extracts (as a post-treatment) with the effects of glyphosate was also studied. Results showed that glyphosate and the extracts of both P. brachypoda and P. birotula reduced the mitotic index as compared with the negative control (distilled water). Surprisingly, however, both extracts from P. brachypoda and P. birotula caused a partial reversal of the antiproliferative effect of glyphosate when used as a post-treatment. Glyphosate also induced the highest number of cells with chromosomal alterations, which was followed by that of P. birotula extracts. However, the extracts from P. brachypoda did not show any significant genotoxic effect. Post-treatment of glyphosate-treated samples with distilled water allowed a partial recovery of the genotoxic effect of glyphosate, and some of the Psychotria extracts also did so. Notably, post-treatment of glyphosate-treated samples with P. brachypoda extracts induced a statistically significant apoptotic effect. It is concluded that P. brachypoda extracts show antiproliferative effects and are not genotoxic, while extracts of P. birotula show a less potent antiproliferative effect and may induce chromosomal abnormalities. The finding of a partial reversion of the effects of glyphosate by a post-treatment with extracts from both plants should be followed up.

  11. Growth and Yield of Glyphosate-Resistant Corn under Different Timing of Glyphosate Application

    OpenAIRE

    N. Desmarwansyah; E. Purba

    2008-01-01

    A field experiment was conducted in 2002 in Langkat, North Sumatra, to determine the effects of glyphosate application timing on the growth and grain yield of glyphosate-resistant corn. Glyphosate at 1,500 g ha-1 was applied at twelve different treatments namely at the V3 stage, the V4 stage, the V5 stage, the V6 stage, the V7 stage, the V8 stage, the V9 stage, the V10 stage, the V12 stage, the V3 stage followed by at the V7 stage, the V3 stage followed by at V12 stage and the V4 stage...

  12. Leaching of glyphosate and AMPA under two soil management practices in Burgundy vineyards (Vosne-Romanee, 21-France)

    International Nuclear Information System (INIS)

    Some drinking water reservoirs under the vineyards of Burgundy are contaminated with herbicides. Thus the effectiveness of alternative soil management practices, such as grass cover, for reducing the leaching of glyphosate and its metabolite, AMPA, through soils was studied. The leaching of both molecules was studied in structured soil columns under outdoor conditions for 1 year. The soil was managed under two vineyard soil practices: a chemically treated bare calcosol, and a vegetated calcosol. After 680 mm of rainfall, the vegetated calcosol leachates contained lower amounts of glyphosate and AMPA (0.02% and 0.03%, respectively) than the bare calcosol leachates (0.06% and 0.15%, respectively). No glyphosate and only low amounts of AMPA (<0.01%) were extracted from the soil. Glyphosate, and to a greater extent, AMPA, leach through the soils; thus, both molecules may be potential contaminants of groundwater. However, the alternative soil management practice of grass cover could reduce groundwater contamination by the pesticide. - Glyphosate and AMPA leached in greater amounts through a chemically treated bare calcosol than through a vegetated calcosol

  13. Glyphosate surfactant herbicide poisoning and management

    Directory of Open Access Journals (Sweden)

    Kranthi Mahendrakar

    2014-01-01

    Full Text Available Glyphosate is a widely used herbicide in agriculture, forestry, industrial weed control and aquatic environments. Glyphosate potential as herbicide was first reported in 1971. It is a non-selective herbicide. It can cause a wide range of clinical manifestations in human beings like skin and throat irritation to hypotension, oliguria and death. We are reporting a case of a 35-year-old male patient who was admitted to our tertiary care hospital following intentional ingestion of around 200 ml of herbicide containing glyphosate. Initially, gastric lavage done and the patient was managed with intubation and mechanical ventilation, noradrenaline and vasopressin infusion, continuous veno-venous hemodiafiltration and intravenous (IV lipid emulsion (20% intralipid 100 ml, patient was successfully treated and discharged home. This case report emphasizes on timely systemic supportive measure as a sole method of treatment since this poison has no known specific antidote and the use of IV lipid emulsion for a successful outcome.

  14. Fuzzy Controller Based Dvr To Mitigate Power Quaity And Reduce The Harmonics Distortion Of Sensitive Load

    OpenAIRE

    SANDESH JAIN; PROF.SHIVENDRA SINGH THAKUR; PROF. S.P.PHULAMBRIKAR

    2013-01-01

    PI controller is very common in the control of DVRs. However, one disadvantage of this conventional controller is its inability to still working well under a wider range of operating conditions. So, as a solution fuzzy controller is proposed. This paper discusses the design and simulation of dynamic voltage restorer for improve power quality and reduce the harmonics distortion of sensitive load. Power quality problem is an occur as a non-standard voltage, current and frequency. Electronics de...

  15. Aplicação foliar de manganês em soja transgênica tolerante ao glyphosate / Foliar application of manganese in transgenic soybean tolerant to glyphosate

    Scientific Electronic Library Online (English)

    Claudir José, Basso; Antônio Luis, Santi; Fabiane Pinto, Lamego; Eduardo, Girotto.

    2011-10-01

    Full Text Available O amarelecimento da soja Roundup Ready após aplicação do glyphosate pode estar associado à deficiência momentânea de manganês. Por isso, com a hipótese de que soja tolerante ao glyphosate necessitaria de uma adição suplementar de manganês, o objetivo deste trabalho foi avaliar diferentes manejos na [...] aplicação foliar de manganês sobre alguns parâmetros da soja. Foram desenvolvidos dois experimentos, um no município de Taquaruçú do Sul e outro em Boa Vista das Missões, RS, no ano agrícola 2009/2010. Foram testados os seguintes tratamentos: 1) sem aplicação de glyphosate, com controle manual das plantas daninhas e sem aplicação foliar de manganês (testemunha); 2) sem aplicação de glyphosate, com controle manual das plantas daninhas e uma aplicação foliar de manganês sete dias após esse controle manual das plantas daninhas; 3) com aplicação de glyphosate e sem aplicação foliar de manganês; 4) aplicação de glyphosate em mistura com manganês; 5) aplicação de glyphosate mais uma aplicação foliar de manganês sete dias após aplicação do glyphosate; 6) aplicação de glyphosate mais aplicação foliar de manganês parcelada em duas épocas, aos 7 e 14 dias após aplicação do glyphosate; 7) aplicação de glyphosate e uma aplicação foliar de manganês aos 14 dias após aplicação de glyphosate. A aplicação de glyphosate foi realizada no estádio V5 da soja, na dose de 720g L-1 e.a, enquanto a dose de Mn utilizada foi 2,0L ha-1 de uma formulação contendo 14% (m/v) de manganês solúvel. Não houve diferença significativa entre os tratamentos para as variáveis estatura de plantas e altura de inserção da primeira vagem. A aplicação de glyphosate não afetou a absorção e o teor foliar de manganês e nitrogênio na cultura da soja. Mesmo com aumento no teor foliar de manganês com a suplementação de manganês, não houve incremento na produtividade da soja. Isso mostra que em solos com teores de Mn acima do suficiente a aplicação do herbicida glifosato não requer a suplementação foliar de manganês em soja geneticamente modificada tolerante a esse herbicida. Abstract in english The yellowing of Roundup Ready soybean after glyphosate application, can be associated to a momentary manganese deficiency. Because of that, with the hypothesis that glyphosate tolerant soybean would need supplementary addition of manganese, the objective of this research was to evaluate different m [...] anagements in the foliar application of manganese in some soybean parameters. It was developed two experiments, one at Taquaruçú do Sul and other at Boa Vista das Missões, RS in the year of 2009/2010. It was tested the following treatments: 1) without glyphosate application with manual weed control and without manganese foliar application (untreated check); 2) without glyphosate application with manual weed control and one manganese foliar application at 7 days after this manual weed control; 3) with glyphosate application and without manganese foliar application; 4) glyphosate application in mixture with manganese; 5) glyphosate application added of one manganese foliar application at 7 days after glyphosate application; 6) glyphosate application added of manganese foliar application split in two times, at 7 and 14 days after glyphosate application; 7) glyphosate application and one of manganese foliar application at 14 days after glyphosate application. The glyphosate application was realized in the V5 soybean stage, using 720g L-1 i.e, while the used dose of Mn was 2.0L ha-1 of a formulation with 14% (m/v) of Mn. There were no significant difference among the treatments to plant height and height insertion of the first legume. The glyphosate application did not affect the absorption and the foliar amount of manganese and nitrogen in soybean crop. Even with the increase in foliar manganese amount, there was no increasing in soybean productivity. This shows that in soils with Mn levels above of the sufficient, it is not necessary foliar manganese addition in genet

  16. Determination of glyphosate residues in plants by precolumn derivatization and coupled-column liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Hernández, F; Hidalgo, C; Sancho, J V

    2000-01-01

    A rapid method was developed for the trace-level determination of glyphosate in olives. After extraction of the glyphosate with water-dichloromethane and simultaneous removal of the olive oil, an aliquot of the aqueous extract is derivatized with 9-fluoroenylmethyl chloroformate (9-fluorenylmethoxycarbonyl chloride; FMOC-CI) to produce a highly fluorescent derivative. A 2 mL aliquot of this extract is injected directly into a coupled-column liquid chromatography system with fluorimetric detection (LC/LC-FD). The procedure was validated by recovery experiments at 3 spiking levels; recoveries ranged from 80 to 97% with relative standard deviations of 3-6%. The limits of detection and quantitation were estimated to be 0.01 and 0.05 mg/kg, respectively. The method was also applied to other plant materials, i.e., tomato plants, strawberry plants, and pear trees (branches, leaves, and fruits) suspected to be contaminated by glyphosate. In all these cases, the extraction was performed in aqueous media. The derivatization reaction was modified by increasing the FMOC-CI concentration, to ensure a quantitative reaction between analyte and reagent in the presence of high levels of coextractives, which also react with FMOC-CI. The final determination was by LC/LC-FD, yielding a rapid, selective, and sensitive method for the determination of glyphosate residues in these samples. The method was tested with real-world samples after application of glyphosate to the surrounding area of crops. PMID:10868597

  17. Quantifying sublethal effects of glyphosate and Roundup® to Daphnia magna using a fluorescence based enzyme activity assay and video tracking

    DEFF Research Database (Denmark)

    Roslev, Peter; R. Hansen, Lone

    Glyphosate (N-(phosphonomethyl)glycine) is the active ingredient in a range of popular broad-spectrum, non-selective herbicide formulations. The toxicity of this herbicide to non-target aquatic organisms such as Daphnia magna is often evaluated using conventional toxicity assays that focus on endpoints such as immobility and mortality. In this study, we investigated sublethal effects of glyphosate and Roundup® to D. magna using video tracking for quantifying behavioral changes, and a novel fluorescence based assay for measuring in vivo hydrolytic enzyme activity (FLEA assay). Roundup® exposure resulted in concentration-dependent inhibition of alkaline phosphatase activity in D. magna. The inhibition of alkaline phosphatase by Roundup® was temperature-dependent with lowest inhibition at 14 °C and greater inhibition at 20 and 26 °C. Exposure of D. magna to sublethal concentrations of glyphosate resulted in behavioral effects quantified as decreases in average swimming velocity and distance moved whereas the inactive time in defined arenas increased. Exposure of D. magna to binary mixtures of glyphosate and copper (Cu) attenuated acute metal toxicity. The results suggest that a combination of assays targeting in vivo enzyme activity and behavioral changes may be applied as a quantitative and sensitive tool for detecting sublethal effects of glyphosate and Roundup® to D. magna. The inhibitory effect of Roundup® on alkaline phosphatase in non-target organisms warrants further investigations.

  18. Civility in scientific publishing: The glyphosate paper

    Science.gov (United States)

    Blaylock, Russell Lane

    2015-01-01

    In recent years, we have witnessed a decline in civility in the public arena when various socially sensitive issues are being presented. Those of us engaged in the publishing of scientific papers and in our comments on these papers, need to be cognizant of the social graces, courteous demeanor, and chivalry. Debates are essential to our learning and in being able to ferret out the essentials of various scientific issues that are of value. Because of the amount of time and effort connected with analyzing the complex problems and the years invested in such endeavors, we often resort to the behavior, that is, contentious and at times even quite insulting to our opponents during our defense. This is the part of human nature but as civilized human beings, we must strive to maintain the courtesy and a calm demeanor during such discussions and debates. I have yielded to such temptations myself but am striving to repent of my sins. The medical and scientific history should have taught us that in defending our ideas we learn and sometimes come to the realization that our paradigm or hypothesis is wrong, either in part or whole. Such debates allow us to fine tune our ideas and correct our errors in thinking, which are easily, consciously, or subconsciously sublimated by our enthusiasm. The glyphosate papers presented ideas that, while well supported by the scientific studies and logical conclusions, also contained some possible errors in its suppositions. Dr. Miguel Faria challenged some of these concepts and was met with some degree of derision by one of the authors. This editorial comment is in response to these issues. PMID:26543672

  19. Civility in scientific publishing: The glyphosate paper.

    Science.gov (United States)

    Blaylock, Russell Lane

    2015-01-01

    In recent years, we have witnessed a decline in civility in the public arena when various socially sensitive issues are being presented. Those of us engaged in the publishing of scientific papers and in our comments on these papers, need to be cognizant of the social graces, courteous demeanor, and chivalry. Debates are essential to our learning and in being able to ferret out the essentials of various scientific issues that are of value. Because of the amount of time and effort connected with analyzing the complex problems and the years invested in such endeavors, we often resort to the behavior, that is, contentious and at times even quite insulting to our opponents during our defense. This is the part of human nature but as civilized human beings, we must strive to maintain the courtesy and a calm demeanor during such discussions and debates. I have yielded to such temptations myself but am striving to repent of my sins. The medical and scientific history should have taught us that in defending our ideas we learn and sometimes come to the realization that our paradigm or hypothesis is wrong, either in part or whole. Such debates allow us to fine tune our ideas and correct our errors in thinking, which are easily, consciously, or subconsciously sublimated by our enthusiasm. The glyphosate papers presented ideas that, while well supported by the scientific studies and logical conclusions, also contained some possible errors in its suppositions. Dr. Miguel Faria challenged some of these concepts and was met with some degree of derision by one of the authors. This editorial comment is in response to these issues. PMID:26543672

  20. Influência do Glyphosate sobre a nodulação e o crescimento de cultivares de soja resistente ao Glyphosate / Glyphosate influence on growth and nodulation of Glyphosate resistant soybean cultivars

    Scientific Electronic Library Online (English)

    R.S., Oliveira JR.; E.C., Dvoranen; J., Constantin; S.D., Cavalieri; L.H.M., Franchini; F.A., Rios; E., Blainski.

    Full Text Available A soja resistente ao glyphosate (RR) é uma tecnologia que vem acrescentar mais uma ferramenta ao manejo de plantas daninhas para essa cultura, que possui a maior área plantada em nosso país. Por se tratar de uma técnica recente tanto no Brasil quanto no mundo, é preciso estudos buscando informações [...] para o uso correto desta importante e cada vez mais freqüente prática agrícola: o cultivo de soja transgênica. Objetivou-se com este trabalho avaliar os efeitos causados pelas aplicações de glyphosate sobre 20 cultivares de soja RR. As doses utilizadas foram: testemunha sem herbicida; glyphosate em aplicação seqüencial de 0,54/0,36 kg equivalente ácido (e.a.) ha-1, aos 12/24 dias após a emergência (DAE); glyphosate em aplicação única de 0,72 kg e.a. ha-1, aos 20 DAE; glyphosate em aplicação seqüencial de 0,72/0,54 kg ha-1, aos 12/24 DAE; e glyphosate em aplicação única de 0,90 kg ha-1, aos 24 DAE. Foram avaliadas as variáveis matéria seca do sistema radicular (MSSR), matéria seca da parte aérea (MSPA), matéria seca dos nódulos acumulados (MSNT) e número de nódulos acumulados (NN). Os cultivares que demonstraram maior suscetibilidade às aplicações de glyphosate foram: MSOY 8008 RR, ANTA RR, CD 213 RR, MSOY 8100 RR, VALIOSA RR, CD 219 RR, MSOY 6001 RR, CRISTALINA RR e BRS 247 RR, apresentando reduções de pelo menos três das quatro variáveis estudadas. BRS 242 RR, BRS 243 RR, BRS 244 RR, BRS 246 RR, CD 214 RR, MSOY 8151 RR, MSOY 9000 RR e BRS 245 RR foram as mais tolerantes, pois não sofreram reduções significativas em nenhuma ou em uma das variáveis avaliadas. De modo geral, a MSSR foi mais afetada pela modalidade de aplicação do que pela dose de glyphosate; por outro lado, a MSPA e a nodulação foram mais afetadas em cultivares de ciclo mais longo, em relação às variedades de ciclo precoce. A nodulação também foi menos afetada pelo glyphosate em variedades do grupo BRS, comparada aos demais materiais genéticos. Abstract in english Glyphosate resistant soybean (GR) is a new technological tool in weed management applied in soybean culture, which accounts for the largest area planted in Brazil. Since it has been only recently applied in Brazil and abroad, further studies are needed to search for useful information on the correct [...] use of this important and increasingly applied agricultural practice: the cultivation of GR soybean. Thus, the aim of this work was to evaluate the effects caused by glyphosate applications on twenty GR soybean cultivars. The rates applied were: check without herbicide; sequential application of glyphosate at 0.54/0.36 kg acid equivalent (AE) ha ¹, at 12/24 days after emergence (DAE); single application of glyphosate at 0.72 kg a.i. ha-1, at 20 DAE; sequential application of glyphosate at 0.72/0.54 kg a.i. ha-1, at 12/24 DAE; single application of glyphosate at 0.90 kg ha-1, at 24 DAE. The variables root dry weight (RDW), shoot dry weight (SDW), accumulated nodule dry weight (ANDW) and number of accumulated nodules (NAN) were evaluated. The cultivars MSOY 8008 RR, ANTA RR, CD 213 RR, MSOY 8100 RR, VALIOSA RR, CD 219 RR, MSOY 6001 RR, CRISTALINA RR and BRS 247 RR showed the highest susceptibility to the glyphosate applications, with reductions in at least three out of the four variables studied. BRS 242 RR, BRS 243 RR, BRS 244 RR, BRS 246 RR, CD 214 RR, MSOY 8151 RR, MSOY 9000 RR and BRS 245 RR showed the highest tolerance, with no significant reductions or only in one of the four assessed variables. In general, RDW was more affected by the mode of application than the glyphosate rate; however, SDW and nodulation (ANDW and NAN) were more affected in the longer cycle cultivars, compared to the earlier cycle varieties. Nodulation was also less affected by glyphosate in the BRS variety group, compared to other genetic materials.

  1. Simplified analysis of glyphosate and aminomethylphosphonic acid in water, vegetation, and soil by liquid chromatography-tandem mass spectrometry

    Science.gov (United States)

    A simple, fast, efficient, and sensitive method was developed for analysis of glyphosate and its degradate, aminomethylphosphonic acid (AMPA), in water, vegetation, and soil. Aqueous extracts were passed through reverse phase and cation exchange columns and directly injected into a tandem mass spect...

  2. Interação de glyphosate com carfentrazone-ethyl Glyphosate - carfentrazone-ethyl interaction

    OpenAIRE

    R.C. Werlang; Silva, A. A.

    2002-01-01

    Foi conduzido um experimento em condições controladas para determinar a interação do carfentrazone-ethyl em mistura no tanque com o herbicida glyphosate, no controle de seis espécies de plantas daninhas. Glyphosate aplicado isoladamente na dose de 720 g ha-1 foi eficaz no controle de Amaranthus hybridus (100%), Desmodium tortuosum (100%), Bidens pilosa (99%), Eleusine indica (96%), Digitaria horizontalis (100%) e Commelina benghalensis (93%) aos 21 DAA. Carfentrazone-ethyl aplicado isoladamen...

  3. Manejo de Conyza bonariensis resistente ao herbicida glyphosate Management of Glyphosate-resistant Conyza bonariensis

    OpenAIRE

    J.M Paula; L. VARGAS; D Agostinetto; M.A Nohatto

    2011-01-01

    C. bonariensis (Conyza bonariensis) é uma planta daninha da família Asteraceae, amplamente distribuída no Brasil, com presença marcante nos Estados do Rio Grande do Sul e do Paraná. Biótipos de C. bonariensis resistentes ao glyphosate foram identificados nos Estados do Rio Grande do Sul, Paraná e São Paulo. O objetivo deste trabalho foi avaliar o efeito de diferentes manejos de inverno e na pré-semeadura da soja sobre a população de plantas de C. bonariensis resistente ao herbicida glyphosate...

  4. Toxicity of formulated glyphosate (glyphos) and cosmo-flux to larval Colombian frogs 1. Laboratory acute toxicity.

    Science.gov (United States)

    Bernal, M H; Solomon, K R; Carrasquilla, G

    2009-01-01

    The spraying of coca (Erythroxylum coca) with glyphosate in Colombia has raised concerns about possible impacts on amphibians. There are few toxicity data for species other than those from temperate regions, and these have not been generated with the combination of formulated glyphosate (Glyphos) and the adjuvant, Cosmo-Flux (coca mix) as used in coca control in Colombia. In order to characterize toxicity of the spray mixture to frogs from Colombia, Gosner stage-25 tadpoles of Scinax ruber, Dendropophus microcephalus, Hypsiboas crepitans, Rhinella granulosa, Rhinella marina, Rhinella typhonius, Centrolene prosoblepon, and Engystomops pustulosus were exposed to the coca mix at concentrations of glyphosate ranging from 1 to 4.2 mg a.e./L diluted in dechlorinated tap water in glass containers. Cosmo-Flux was added to Glyphos in the proportion of 2.3% v/v, as used in aerial application for coca control. Exposures were for 96 h at 23 +/- 1.5 degrees C with 12:12-h light/dark cycle. Test solutions were renewed every 24 h. Concentrations, measured within the first hour and at 24 and 96 h using enzyme-linked immunosorbent assay (ELISA) (Abraxis, LLC), ranged from 70 to 130% of nominal values. LC50 values ranged from 1200 to 2780 microg glyphosate acid equivalents (a.e.)/L for the 8 species tested. Data suggest that sensitivity to Roundup-type formulations of glyphosate in these species is similar to that observed in other tropical and temperate species. In addition, sensitivity of larval amphibians to Roundup-type formulations spans a relatively narrow range. Finally, toxicity of the mixture as used to spray coca was likely driven by the surfactant in the glyphosate formulation, as the addition of Cosmo-Flux did not enhance toxicity above those reported for Vision = Roundup. PMID:19672764

  5. Effect of Reducing Groundwater on the Retardation of Redox-Sensitive Radionuclides

    International Nuclear Information System (INIS)

    Laboratory batch sorption experiments were used to investigate variations in the retardation behavior of redox-sensitive radionuclides. Water-rock compositions used during these experiments were designed to simulate subsurface conditions at the Nevada Test Site (NTS), where a suite of radionuclides were deposited as a result of underground nuclear testing. Experimental redox conditions were controlled by varying the oxygen content inside an enclosed glove box and by adding reductants into the testing solutions. Under atmospheric (oxidizing) conditions, the radionuclide distribution coefficients varied with the mineralogical composition of the sorbent and the water chemistry. Under reducing conditions, distribution coefficients showed marked increases for 99Tc and 237Np in devitrified tuff, but much smaller variations in alluvium, carbonate rock, and zeolitic tuff. This effect was particularly important for 99Tc, which tends to be mobile under oxidizing conditions. Unlike other redox-sensitive radionuclides, iodine sorption may decrease under reducing conditions when I- is the predominant species. Overall, sorption of U to alluvium, devitrified tuff, and zeolitic tuff under atmospheric conditions was less than in the glove-box tests. However, the mildly reducing conditions achieved here were not likely to result in substantial U(VI) reduction to U(IV). Sorption of Pu was not affected by the decreasing redox conditions achieved in this study, as the predominant sorbed Pu species in all conditions was expected to be the low-solubility and strongly sorbing Pu(OH)4. Depending on the aquifer lithology, the occurrence of reducing conditions along a groundwater flowpath could potentially contribute to the retardation of redox-sensitive radionuclides 99Tc and 237Np, which are commonly identified as long-term dose contributors in the risk assessment in various nuclear facilities.

  6. Effect of Reducing Groundwater on the Retardation of Redox-Sensitive Radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Zavarin, M; Rose, T P

    2008-04-21

    Laboratory batch sorption experiments were used to investigate variations in the retardation behavior of redox-sensitive radionuclides. Water-rock compositions used during these experiments were designed to simulate subsurface conditions at the Nevada Test Site (NTS), where a suite of radionuclides were deposited as a result of underground nuclear testing. Experimental redox conditions were controlled by varying the oxygen content inside an enclosed glove box and by adding reductants into the testing solutions. Under atmospheric (oxidizing) conditions, the radionuclide distribution coefficients varied with the mineralogical composition of the sorbent and the water chemistry. Under reducing conditions, distribution coefficients showed marked increases for {sup 99}Tc and {sup 237}Np in devitrified tuff, but much smaller variations in alluvium, carbonate rock, and zeolitic tuff. This effect was particularly important for {sup 99}Tc, which tends to be mobile under oxidizing conditions. Unlike other redox-sensitive radionuclides, iodine sorption may decrease under reducing conditions when I{sup -} is the predominant species. Overall, sorption of U to alluvium, devitrified tuff, and zeolitic tuff under atmospheric conditions was less than in the glove-box tests. However, the mildly reducing conditions achieved here were not likely to result in substantial U(VI) reduction to U(IV). Sorption of Pu was not affected by the decreasing redox conditions achieved in this study, as the predominant sorbed Pu species in all conditions was expected to be the low-solubility and strongly sorbing Pu(OH){sub 4}. Depending on the aquifer lithology, the occurrence of reducing conditions along a groundwater flowpath could potentially contribute to the retardation of redox-sensitive radionuclides {sup 99}Tc and {sup 237}Np, which are commonly identified as long-term dose contributors in the risk assessment in various nuclear facilities.

  7. Características fisiológicas de biótipos de Conyza bonariensis Resistentes ao glyphosate cultivados sob competição / Physiological characteristics of Conyza bonariensis biotypes resistant to glyphosate cultivated under competition

    Scientific Electronic Library Online (English)

    L., Galon; E.A., Ferreira; G., Concenço; A.A., Silva; D.V., Silva; A.F., Silva; I, Aspiazú; L., Vargas.

    2013-12-01

    Full Text Available A resistência de plantas daninhas a herbicidas está relacionada a modificações metabólicas, enzimáticas, fisiológicas e/ou anatômicas. Aliado a essas mudanças, a planta pode aumentar ou diminuir as atividades fisiológicas, o que, consequentemente, pode afetar o seu crescimento e desenvolvimento. Ass [...] im, biótipos resistentes podem apresentar melhor adaptação ecológica em ambientes de cultivo e tornar-se predominantes devido à eliminação das plantas sensíveis. Em condições de seleção natural, biótipos com maior adaptação ecológica apresentam maior produção que biótipos menos adaptados. Neste trabalho, avaliou-se o efeito da competição em características fisiológicas de biótipos de Conyza bonariensis suscetíveis e resistentes ao herbicida glyphosate. Os tratamentos constaram de plantas de dois biótipos de C. bonariensis - um comprovadamente resistente e um suscetível ao glyphosate, dispostas em modelo aditivo de estudo de competição. No centro da unidade experimental foram semeadas três sementes do biótipo considerado como o tratamento: resistente (R) ou suscetível (S), sendo essa planta rodeada por 0 (testemunha sem competição), 1, 2, 3, 4, ou 5 plantas do biótipo oposto. O biótipo suscetível apresentou-se mais tolerante à competição com plantas do biótipo oposto no tocante às características fisiológicas avaliadas. O biótipo resistente de buva apresenta desvantagem fisiológica em relação ao suscetível e, consequentemente, menor potencial de adaptabilidade na ausência do fator de seleção - o herbicida glyphosate. Abstract in english The resistance of weeds to herbicides is related to metabolic, enzymatic, physiological and anatomical changes. Coupled with these changes, plants can increase or decrease their physiological activities, which can affect their growth and development. Thus, resistant biotypes may have a higher ecolog [...] ical adaptation in these environments and become predominant due to the elimination of sensitive plants. Under natural selection conditions, biotypes with greater ecological adaptation show higher production than less adapted biotypes. Thus, the aim of this work was to assess the effect of competition on the physiological characteristics of Conyza bonariensis biotypes susceptible and resistant to the herbicide glyphosate. The treatments consisted of plants of two biotypes of C. bonariensis - one proven to be resistant and one susceptible to glyphosate. In the center of the experimental unit, three seeds of the C. bonariensis biotype considered for treatment - resistant (R) or susceptible (S) - were sown , with the plant being surrounded by 0 (no competition), 1, 2, 3, 4, or 5 plants of the opposite biotype. The susceptible biotype presented a higher tolerance to competition with plants of the opposite biotype regarding the physiological characteristics evaluated. The resistant biotype of C. bonariensis has a physiological disadvantage compared to the susceptible one and, therefore, less potential for adaptability in the absence of the selection factor - the herbicide glyphosate.

  8. Chemical control alternatives for sourgrass (Digitaria insularis resistant to glyphosate

    Directory of Open Access Journals (Sweden)

    Marcel Sereguin Cabral de Melo

    2012-08-01

    Full Text Available Herbicides alternatives for controlling sourgrass (Digitaria insularis weed in infested citrus areas are limited, mainly due to the few options of registered herbicides and by the modalities in that these chemical products are used (directed applications. Thus it is important to evaluate other post-emergence herbicides, to be used in association with glyphosate, for the efficient control of glyphosate-resistant biotype of sourgrass (Digitaria insularis, resistant to glyphosate.  The experiment was conducted in Matão County, Sao Paulo State, in area belonging to Cambuhy Farm, during September to October 2009, in areas presenting biotypes of D. insularis resistant to glyphosate. Application occurred when sourgrass plants were with 3 to 5 tillers stage. Treatments consisted of different herbicides in association with glyphosate. It was conducted control visual assesments at 7, 14, 21, 28 and 35 days after application and collecting and weighting of weed dry mass dossel. Treatments that showed better results were glyphosate in association with clethodim, complemented by paraquat + diuron 7 days after the first application and glyphosate in association with clethodim complemented by  ammonium-glufosinate 7 days after the first application. Further, glyphosate treatments mixture to haloxyfop-methyl, glyphosate + fenoxaprop-p-ethyl + clethodim and glyphosate + tepraloxydim showed excelent performance, even with just one application.

  9. Deriva simulada de formulações comerciais de glyphosate sobre maracujazeiro amarelo Drift simulation of glyphosate commercial formulations on yellow passion fruit growth

    Directory of Open Access Journals (Sweden)

    A. Wagner Júnior

    2008-01-01

    Full Text Available Objetivou-se com este trabalho avaliar os efeitos da deriva de formulações comerciais de glyphosate no desenvolvimento de plantas jovens de maracujazeiro amarelo. O trabalho foi realizado em casa de vegetação do Departamento de Fitotecnia da Universidade Federal de Viçosa, durante o período de março a abril de 2007. Foi utilizado o delineamento experimental de blocos casualizados, em esquema fatorial 3 x 4 + 1, em que três foram as formulações de glyphosate e cinco foram as doses utilizadas acrescidas de testemunha sem herbicida. O trabalho foi conduzido com cinco repetições, sendo cada planta considerada como parcela experimental. As formulações comerciais aplicadas foram Roundup Transorb®, Roundup Original® e Zapp QI®, utilizando-se as seguintes doses (g e.a ha-1: 43,2; 86,4; 172,8; e 345,6 g ha-1. Aos 28 dias após a aplicação (DAA, avaliaram-se os comprimentos da parte aérea, da raiz e total (cm; o diâmetro do caule (mm; o número de folhas e de ramificações primárias; a massa seca da parte aérea e da raiz das plantas (g; e a área foliar por planta (cm². Aos 7, 14 e 28 DAA, avaliou-se, visualmente, a porcentagem de intoxicação das plantas. O glyphosate em deriva simulada, independentemente das formulações utilizadas, ocasionou injúrias no maracujazeiro amarelo, acarretando redução no crescimento e desenvolvimento das plantas. As formulações Roundup Transorb® e Roundup Original® foram mais prejudiciais às plantas que o Zapp Qi®. O maracujazeiro amarelo mostrou-se suscetível à deriva, devendo o glyphosate ser usado com cuidado, de maneira a atingir somente as plantas daninhas a serem controladas.The aim of this work was to evaluate the effects of drift simulation of commercial formulations of glyphosate on the growth of young plants of yellow passion fruit. The work was carried out at the Plant Science Department of the Universidade Federal de Viçosa (MG, Brazil, from March to April 2007. The experiment was arranged in a completely randomized block design, with five replications, in a factorial 3 x 4 + 1, consisting of three glyphosate formulations and five doses, (one being the control without herbicide. Each plot was constituted by one plant. The applied doses of glyphosate were 43.2; 86.4; 172.8 and 345.6 g ha-1, using the commercial formulations: Roundup Transorb®, Roundup Original® and Zapp QI®. After 28 days of application, aerial part, root and total length (cm, stem diameter (mm, number of leaves and primary ramifications, aerial part and root dry mass,(g and the foliar area per plant (cm² were evaluated. After 7, 14 and 28 application days, intoxication percentage of the plants was also evaluated. Regardless of the formulations used, glyphosate drift simulation caused injury to the yellow passion fruit, reducing plant growth. The herbicides Roundup Transorb® and Roundup Original® were more harmful than Zapp Qi®. The yellow passion fruit was susceptible to drift simulation; thus, glyphosate must be used carefully, so as to reach only the weeds to be controlled.

  10. Ultrafast and sensitive room temperature NH3 gas sensors based on chemically reduced graphene oxide

    International Nuclear Information System (INIS)

    Ultrafast and sensitive room temperature NH3 gas sensors based on chemically reduced graphene oxide (rGO) are demonstrated in this work. rGO, which was prepared via the reduction of graphene oxide by pyrrole, exhibited excellent responsive sensitivity and selectivity to ammonia (NH3) gas. The high sensing performance of these rGO sensors with resistance change as high as 2.4% and response time as fast as 1.4 s was realized when the concentration of NH3 gas was as low as 1 ppb. Furthermore, the rGO sensors could rapidly recover to their initial states with IR illumination. The devices also showed excellent repeatability and selectivity to NH3. These rGO sensors, with low cost, low power, and easy fabrication, as well as scalable properties, showed great potential for ultrasensitive detection of NH3 gas in a wide variety of fields. (paper)

  11. 75 FR 17768 - Glyphosate From China

    Science.gov (United States)

    2010-04-07

    ....8 of the Commission's rules, as amended, 67 FR 68036 (November 8, 2002). Even where electronic...(C) of the Commission's Handbook on Electronic Filing Procedures, 67 FR 68168, 68173 (November 8... Glyphosate From China AGENCY: United States International Trade Commission. ACTION: Institution...

  12. 78 FR 60707 - Glyphosate; Pesticide Tolerances

    Science.gov (United States)

    2013-10-02

    ... with glyphosate follows. In the Federal Register of May 1, 2013 (78 FR 25396) (FRL-9384-3), EPA issued... April 20, 2011 (76 FR 22067) (FRL-8869- 7), EPA issued a document pursuant to FFDCA section 408(d)(3... Register of May 1, 2013 (78 FR 25396), EPA concludes that there is a reasonable certainty that no harm...

  13. 75 FR 20862 - Glyphosate From China

    Science.gov (United States)

    2010-04-21

    ... established a schedule for the conduct of the subject investigation (75 FR 17768, April 7, 2010). Subsequently... From the Federal Register Online via the Government Printing Office INTERNATIONAL TRADE COMMISSION Glyphosate From China AGENCY: United States International Trade Commission. ACTION: Revised schedule for...

  14. Time-division SQUID multiplexers with reduced sensitivity to external magnetic fields

    CERN Document Server

    Stiehl, G M; Hilton, G C; Irwin, K D; Mates, J A B; Reintsema, C D; Zink, B L

    2010-01-01

    Time-division SQUID multiplexers are used in many applications that require exquisite control of systematic error. One potential source of systematic error is the pickup of external magnetic fields in the multiplexer. We present measurements of the field sensitivity figure of merit, effective area, for both the first stage and second stage SQUID amplifiers in three NIST SQUID multiplexer designs. These designs include a new variety with improved gradiometry that significantly reduces the effective area of both the first and second stage SQUID amplifiers.

  15. Effectiveness of the nitrate sensitive areas scheme in reducing groundwater concentrations in England

    OpenAIRE

    Silgram, M.; Williams, A.; Waring, R; Neumann, I.; Hughes, A.; Mansour, M.; Besien, T van

    2005-01-01

    The Nitrates Sensitive Areas (NSA) Scheme in England was a voluntary, compensated measure from 1990 to 2003 which aimed to reduce nitrate leaching from agricultural land to vulnerable groundwaters by modifying land use management. Measurements from 22 NSAs introduced in 1994/5 show an overall 34% decrease in the nitrate concentration of water leaching from the soils from 115?mg/l (1994/5-1995/6) to 76?mg/l (1998/9-1999/2000). This study looks at two NSAs in depth. The Old Chalford NSA consist...

  16. Refractory cardiopulmonary failure after glyphosate surfactant intoxication: a case report

    OpenAIRE

    Chang Chia-Chu; Chang Chirn-Bin

    2009-01-01

    Abstract Background Glyphosate is an herbicide considered to be of low toxicity to humans because its effects are specific to plants. However, fatal reactions to glyphosate have been reported after the ingestion of large amounts. Pulmonary edema, shock, and arrhythmia were the reported causes of mortality. Case presentation We present the case of a 57-year-old woman who was admitted to the emergency department unconsciousness after ingestion of glyphosate surfactant in a suicide attempt. Meta...

  17. PHYTO-MICROBIAL DEGRADATION OF GLYPHOSATE IN RIYADH AREA

    OpenAIRE

    ABDEL-MEGEED A.; SADIK M.W.; AL-SHAHRANI H.O.; ALI H.M.

    2013-01-01

    Greenhouse studies were conducted to determine the ability of plant Amaranth, Amaranthus caudate and two isolated bacterial strains from rhizosphere region for cleaning up glyphosate residues in soil and plants. The analytical study of the biodegradation of glyphosate was carried out in the laboratory conditions. Amaranth, Amaranthus caudate and two isolated bacterial strains namely Pseudomonas aeruginosa and Bacillus megaterium could degrade glyphosate in 5 days. These results suggested that...

  18. Metabolism of glyphosate in Pseudomonas sp. strain LBr.

    OpenAIRE

    Jacob, G S; Garbow, J R; Hallas, L E; Kimack, N M; Kishore, G M; Schaefer, J.

    1988-01-01

    Metabolism of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. strain LBr, a bacterium isolated from a glyphosate process waste stream, was examined by a combination of solid-state 13C nuclear magnetic resonance experiments and analysis of the phosphonate composition of the growth medium. Pseudomonas sp. strain LBr was capable of eliminating 20 mM glyphosate from the growth medium, an amount approximately 20-fold greater than that reported for any other microorganism to date. The bact...

  19. Lethal and Sublethal Effects of Glyphosate (Roundup® Active to Embryos of Colombian Anurans

    Directory of Open Access Journals (Sweden)

    Teófila María Triana Velásquez

    2013-05-01

    Full Text Available Glyphosate is an herbicide widely used in agriculture, which may affect non-target species. The aim of this study was to determine the lethal (Median lethal concentration - LC50 and sublethal effects (changes on body size and development of glyphosate (Roundup® Active to embryos of four anuran species, exposed during 96 hours under laboratory and microcosm tests. Under laboratory conditions, Engystomops pustulosus was the most tolerant species (LC50 = 3033,18 ?g a.e./L and Rhinella marina was the most sensitive (LC50 = 1421,46 ?g a.e./L, which also showed a delayed development and significantly reduced body size. The other species had an intermediate LC50 (Rhinella humboldti = 2899,54 ?g a.e./L; Hypsiboas crepitans = 2151,88 ?g a.e./L. In all cases, the laboratory LC50 was lower than the concentration used in field (5392,92 ?g a.e./L, indicating a high toxic effect. In the microcosm tests, embryos of E. pustulosus were the most tolerant (LC50 = 19,41 kg a.e./ha, while R. humboldti were the most sensitive (LC50 = 10,61 kg a.e./ha. In this case, all four study species had a higher LC50 than the concentration sprayed in field (3,69 kg a.e./ ha, so a lower lethal effect, and there were no significant differences in body size and development. This result shows that the glyphosate, as the commercial presentation Roundup® Active, produce a moderate mortality on anuran embryos.EFECTOS LETALES Y SUBLETALES DEL GLIFOSATO (ROUNDUP® ACTIVO EN EMBRIONES DE ANUROS COLOMBIANOS.El glifosato es un herbicida usado en la agricultura que puede afectar especies no blanco. El objetivo del trabajo fue determinar los efectos letales (concentración letal media - CL50 y subletales (cambios en el tamaño corporal y desarrollo del glifosato (Roundup® Activo sobre embriones de cuatro especies de anuros expuestos durante 96 horas en pruebas de laboratorio y microcosmos. En laboratorio, la especie más tolerante fue Engystomops pustulosus (CL50 = 3033,18 ?g a.e./L y la más sensible Rhinella marina (CL50 = 1421,46 ?g a.e./L, la cual mostró una reducción significativa en el tamaño corporal y retrasos en el desarrollo de los individuos. Las demás especies tuvieron un CL50 intermedio (Rhinella humboldti = 2899,36 ?ga.e./L; Hypsiboas crepitans = 2151,88 ?g a.e./L. En todos los casos el CL50 fue menor a la concentración empleada en campo (5392,92 ?g a.e./ L indicando un efecto tóxico alto. En los microcosmos, los embriones de E. pustulosus fueron los más tolerantes (CL50 = 19,41 kg a.e./ha, mientras que los de R. humboldti los más sensibles (CL50 = 10,61 kg a.e./ha. Sin embargo, todas las especies tuvieron un CL50 superiora la concentración asperjada en campo (3,69 kg a.e./ ha, mostrando un efecto tóxico leve, y no hubo diferencias enel tamaño corporal ni en el desarrollo de los individuos. Este resultado muestra que el glifosato, en su presentación comercial como Roundup® Activo, genera una mortalidad moderada en los embriones de anuros.

  20. Reduced attention-driven auditory sensitivity in hallucination-prone individuals.

    Science.gov (United States)

    Rayner, Louise H; Lee, Kwang-Hyuk; Woodruff, Peter W R

    2015-11-01

    BackgroundEvidence suggests that auditory hallucinations may result from abnormally enhanced auditory sensitivity.AimsTo investigate whether there is an auditory processing bias in healthy individuals who are prone to experiencing auditory hallucinations.MethodTwo hundred healthy volunteers performed a temporal order judgement task in which they determined whether an auditory or a visual stimulus came first under conditions of directed attention ('attend-auditory' and 'attend-visual' conditions). The Launay-Slade Hallucination Scale was used to divide the sample into high and low hallucination-proneness groups.ResultsThe high hallucination-proneness group exhibited a reduced sensitivity to auditory stimuli under the attend-auditory condition. By contrast, attention-directed visual sensitivity did not differ significantly between groups.ConclusionsHealthy individuals prone to hallucinatory experiences may possess a bias in attention towards internal auditory stimuli at the expense of external sounds. Interventions involving the redistribution of attentional resources would have therapeutic benefit in patients experiencing auditory hallucinations. PMID:26382950

  1. Fuzzy Controller Based Dvr To Mitigate Power Quaity And Reduce The Harmonics Distortion Of Sensitive Load

    Directory of Open Access Journals (Sweden)

    SANDESH JAIN

    2013-05-01

    Full Text Available PI controller is very common in the control of DVRs. However, one disadvantage of this conventional controller is its inability to still working well under a wider range of operating conditions. So, as a solution fuzzy controller is proposed. This paper discusses the design and simulation of dynamic voltage restorer for improve power quality and reduce the harmonics distortion of sensitive load. Power quality problem is an occur as a non-standard voltage, current and frequency. Electronics devices are very sensitive load against harmonics. In power system voltage sag, swell, flicker and harmonics are some of the problem to the sensitive load. The compensation capability of a DVR depends primarily on the maximum voltage injection ability and the amount of stored energy available within the restorer. This device is connected in series with the distribution feeder at medium voltage. A fuzzy logic control is proposed. Simulation result carried out by Matlab/Simulink verifies the performance of the proposed method.

  2. Evaluation of reduced allergenicity of irradiated peanut extract using splenocytes from peanut-sensitized mice

    International Nuclear Information System (INIS)

    Peanut (PN) allergy is one of the most serious forms of IgE-mediated food hypersensitivity. Gamma irradiation has been widely used for the preservation of food. The results of our previous studies showed that the IgE-binding capacity to several antigens were profoundly reduced after gamma irradiation. In this study, we evaluated the changes of allergenecity and cytokine production profiles after exposure of irradiated PN extract in a PN-allergy mouse model. Mice were sensitized to PN extract by intragastric administration on days 0, 1, 2, and 7, and then challenged on day 21. Four weeks later, we evaluated the cytokine production patterns and proliferation responses of splenocytes that were stimulated with intact PN extract, compared to 10 and 50 kGy irradiated PN extract. When the cells were stimulated with 10 kGy of irradiated PN extract, a higher level of production of IFN-? and IL-10 cytokines was observed. However, stimulation with 50 kGy of irradiated PN extract resulted in a higher level of production of only IFN-? cytokines. In addition, the Th1/Th2 ratio increased in response to treatment with gamma-irradiated PNs. The results of this study show that the allergenicity of PN extracts could be reduced by gamma irradiation which caused downregulation of Th2 lymphocyte activity in the PN-sensitized mice.

  3. Evaluation of reduced allergenicity of irradiated peanut extract using splenocytes from peanut-sensitized mice

    Science.gov (United States)

    Oh, Sejo; Jang, Da-In; Lee, Ju-Woon; Kim, Jae-Hun; Byun, Myung-Woo; Lee, Soo-Young

    2009-07-01

    Peanut (PN) allergy is one of the most serious forms of IgE-mediated food hypersensitivity. Gamma irradiation has been widely used for the preservation of food. The results of our previous studies showed that the IgE-binding capacity to several antigens were profoundly reduced after gamma irradiation. In this study, we evaluated the changes of allergenecity and cytokine production profiles after exposure of irradiated PN extract in a PN-allergy mouse model. Mice were sensitized to PN extract by intragastric administration on days 0, 1, 2, and 7, and then challenged on day 21. Four weeks later, we evaluated the cytokine production patterns and proliferation responses of splenocytes that were stimulated with intact PN extract, compared to 10 and 50 kGy irradiated PN extract. When the cells were stimulated with 10 kGy of irradiated PN extract, a higher level of production of IFN-? and IL-10 cytokines was observed. However, stimulation with 50 kGy of irradiated PN extract resulted in a higher level of production of only IFN-? cytokines. In addition, the Th1/Th2 ratio increased in response to treatment with gamma-irradiated PNs. The results of this study show that the allergenicity of PN extracts could be reduced by gamma irradiation which caused downregulation of Th2 lymphocyte activity in the PN-sensitized mice.

  4. Evaluation of reduced allergenicity of irradiated peanut extract using splenocytes from peanut-sensitized mice

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Sejo; Jang, Da-In [Department of Pediatrics, Ajou University School of Medicine, Suwon 442-749 (Korea, Republic of); Lee, Ju-Woon; Kim, Jae-Hun; Byun, Myung-Woo [Team for Radiation Food Science and Biotechnology, Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Lee, Soo-Young [Department of Pediatrics, Ajou University School of Medicine, Suwon 442-749 (Korea, Republic of)], E-mail: jsjs87@ajou.ac.kr

    2009-07-15

    Peanut (PN) allergy is one of the most serious forms of IgE-mediated food hypersensitivity. Gamma irradiation has been widely used for the preservation of food. The results of our previous studies showed that the IgE-binding capacity to several antigens were profoundly reduced after gamma irradiation. In this study, we evaluated the changes of allergenecity and cytokine production profiles after exposure of irradiated PN extract in a PN-allergy mouse model. Mice were sensitized to PN extract by intragastric administration on days 0, 1, 2, and 7, and then challenged on day 21. Four weeks later, we evaluated the cytokine production patterns and proliferation responses of splenocytes that were stimulated with intact PN extract, compared to 10 and 50 kGy irradiated PN extract. When the cells were stimulated with 10 kGy of irradiated PN extract, a higher level of production of IFN-{gamma} and IL-10 cytokines was observed. However, stimulation with 50 kGy of irradiated PN extract resulted in a higher level of production of only IFN-{gamma} cytokines. In addition, the Th1/Th2 ratio increased in response to treatment with gamma-irradiated PNs. The results of this study show that the allergenicity of PN extracts could be reduced by gamma irradiation which caused downregulation of Th2 lymphocyte activity in the PN-sensitized mice.

  5. Shock Reactivity Study on Standard and Reduced Sensitivity Rdx of Different Particle Size Distributions

    Science.gov (United States)

    McGregor, N. M.; Lindfors, A. J.

    2007-12-01

    Embedded gauge experiments have been performed using a three inch high velocity powder gun to assess the effects of RDX particle size and crystal quality on shock induced reactivity in support of the Combat Safe Insensitive Munitions (CSIM) program. Four monomodal experimental compositions containing 73% solids loading by weight and 27% HTPB binder were tested. The compositions were made using either standard or reduced sensitivity grades of RDX in Class 5 or Class 1 150-300 micron sieve cut particle size classes. Results have shown marked changes in the mode of reaction between the two particle size classes. Both RDX grades at the Class 1 sieve cut particle size distribution showed significant reaction at the shock front as well as behind the front. The Class 5 RDX compositions however showed little reaction at the shock front with rapid growth behind the front. Reaction modes were similar but occurring at greater input pressures for the reduced sensitivity grade of RDX compared to the corresponding particle size distribution standard grade RDX counterpart.

  6. Overexpression of salivary-type amylase reduces the sensitivity to bortezomib in multiple myeloma cells.

    Science.gov (United States)

    Mizuno, Shohei; Hanamura, Ichiro; Ota, Akinobu; Karnan, Sivasundaram; Narita, Tomoko; Ri, Masaki; Mizutani, Motonori; Goto, Mineaki; Gotou, Mayuko; Tsunekawa, Norikazu; Shikami, Masato; Iida, Shinsuke; Hosokawa, Yoshitaka; Miwa, Hiroshi; Ueda, Ryuzo; Nitta, Masakazu; Takami, Akiyoshi

    2015-11-01

    Amylase-producing myeloma exhibits refractoriness to chemotherapy and a dismal prognosis. In this study, we established a human myeloma cell line, 8226/AMY1, in which a lentivirally transfected AMY1 gene was stably expressed and explored its biological characteristics. 8226/AMY1 showed a survival advantage over mock control when treated with dexamethasone, bortezomib, and lenalidomide in vitro partly through inhibition of apoptosis induced by these reagents. In a xenograft murine model, 8226/AMY1 showed rapid tumor growth and reduced sensitivity to bortezomib compared with mock. A microarray gene expression analysis identified TCL1A, which functions as a coactivator of the cell survival kinase Akt, differentially up-regulated in 8226/AMY1. The expression of phosphorylated Akt was increased in the 8226/AMY1 cells following bortezomib treatment, but not in the mock cells. In addition, treatment with perifosine, an inhibitor of Akt phosphorylation, enhanced the anti-myeloma effect of bortezomib in the 8226/AMY1 cells. Our data suggest that amylase-producing myeloma reduced the sensitivity to bortezomib in vitro and in vivo, and the up-regulation of TCL1A may influence the drug susceptibility of 8226/AMY1 via the phosphorylation of Akt. These findings provide clues for developing treatment approaches for not only amylase-producing myeloma, but also relapsed and refractory myelomas. PMID:26341959

  7. Klebsiella oxytoca with reduced sensitivity to chlorhexidine isolated from a diabetic foot ulcer.

    Science.gov (United States)

    Vali, Leila; Dashti, Ali A; El-Shazly, Sherief; Jadaon, Mehrez M

    2015-05-01

    In most hospitals, chlorhexidine is used as skin antiseptic prior to clinical procedures, in dressings and when bathing patients. We hereby report, for the first time, the isolation of a clinical Klebsiella oxytoca isolate with reduced sensitivity to chlorhexidine from a foot ulcer of a diabetic patient, which is a common and serious complication associated with diabetes. The Minimum Inhibitory Concentration of the K. oxytoca isolate to chlorhexidine was found to be 30 mg/L and the Minimum Bactericidal Concentration was 60 mg/L. An increased resistance to ethidium bromide (MIC 200 mg/ L) was also observed. Molecular tests revealed that the isolate contained blaCTXM15, blaT(EM-1) and bla(SHV). The other resistant genes detected were qnrB1 and aac(6')-Ib-cr. The resistant determinants were located on a class I integron integrase (intI1) containing qacE gene. DNA sequencing showed homology to K. oxytoca plasmid pACM1. Identification of K. oxytoca with reduced sensitivity to chlorhexidine raises concern regarding dilution standards in hospitals. Adherence to the hospitals' infection control policies should be strictly monitored to avoid continuous low level exposure of bacteria to biocides, specifically in developing countries. PMID:25835102

  8. Association of sulfentrazone and glyphosate for weed control in RR® soybean

    Directory of Open Access Journals (Sweden)

    Jethro Barros Osipe

    2008-04-01

    Full Text Available The use of herbicides with residual activity in weed management has become a common practice in order to reduce weed initial competition. This study aims to evaluate the selectivity and efficiency of the sulfentrazone + glyphosate association at pre-planting management, supplemented with postemergence glyphosate. To reach such intent, an experiment was conducted in Bandeirantes – Pr, on a Eutrophic latosol. The experimental design was randomized blocks in split plot scheme with 11 treatments and 04 replicates. The main weeds in the experimental area (Bidens pilosa, Commelina benghalensis were in full vegetative growth at the time of application management. During this period, injury caused by treatment to soybean crop, weed density, and grain yield were evaluated. The results showed that sulfentrazone significantly reduced the density of Bidens pilosa and Commelina benghalensis, which ensured an increase in yield of up to 22.49%. In addition, no symptoms of injury were observed by the use of herbicides.

  9. Porcine somatotropin alters insulin response in growing pigs by reducing insulin sensitivity rather than changing responsiveness.

    Science.gov (United States)

    Wray-Cahen, D; Dunshea, F R; Boyd, R D; Bell, A W; Bauman, D E

    2012-07-01

    Exogenous porcine somatotropin (pST) treatment consistently improves growth performance and reduces fat deposition in pigs, and it is hypothesized that one component of the mechanism is through altering the sensitivity and/or responsiveness to insulin. Therefore, a study was conducted to investigate the effect of pST treatment on whole-body glucose metabolism in response to varying doses of insulin. Eight barrows were surgically prepared with indwelling catheters and randomly assigned to one of two treatment groups (0 or 120 ?g pST/kg BW · d) for 13 d. Whole-body glucose kinetics were measured during infusion of [6-(3)H]-glucose under basal conditions and during hyperinsulinemic-euglycemic clamps at various insulin infusion rates (7, 28, and 140, and 14, 70, and 280 ng insulin/kg BW · min) and alterations in the dose-response parameters were calculated with nonlinear regression. Treatment with pST increased basal plasma concentrations of glucose (36%; P = 0.005), insulin (276%; P = 0.001), and NEFAs (177%; P = 0.01) and decreased the rate of glucose disappearance (-59%; P = 0.001). The responsiveness (maximum response) for steady state glucose infusion rate to maintain glycemia was not altered by pST (112 vs 106 ?mol/min · kg; P = 0.78), whereas the sensitivity (effective dose at 50% of maximum response) was increased almost 7-fold (1.3 vs 8.7 ng/mL; P = 0.027). Similar responses were observed for rate of glucose disappearance and insulin-dependent glucose utilization. Therefore, pST-induced insulin resistance with regard to whole-body glucose uptake is due to a reduced sensitivity to insulin, rather than a change in responsiveness. PMID:22425435

  10. Effect of reducing groundwater on the retardation of redox-sensitive radionuclides

    Directory of Open Access Journals (Sweden)

    Rose TP

    2008-12-01

    Full Text Available Abstract Laboratory batch sorption experiments were used to investigate variations in the retardation behavior of redox-sensitive radionuclides. Water-rock compositions were designed to simulate subsurface conditions at the Nevada Test Site (NTS, where a suite of radionuclides were deposited as a result of underground nuclear testing. Experimental redox conditions were controlled by varying the oxygen content inside an enclosed glove box and by adding reductants into the testing solutions. Under atmospheric (oxidizing conditions, radionuclide distribution coefficients varied with the mineralogic composition of the sorbent and the water chemistry. Under reducing conditions, distribution coefficients showed marked increases for 99Tc (from 1.22 at oxidizing to 378 mL/g at mildly reducing conditions and 237Np (an increase from 4.6 to 930 mL/g in devitrified tuff, but much smaller variations in alluvium, carbonate rock, and zeolitic tuff. This effect was particularly important for 99Tc, which tends to be mobile under oxidizing conditions. A review of the literature suggests that iodine sorption should decrease under reducing conditions when I- is the predominant species; this was not consistently observed in batch tests. Overall, sorption of U to alluvium, devitrified tuff, and zeolitic tuff under atmospheric conditions was less than in the glove-box tests. However, the mildly reducing conditions achieved here were not likely to result in substantial U(VI reduction to U(IV. Sorption of Pu was not affected by the decreasing Eh conditions achieved in this study, as the predominant sorbed Pu species in all conditions was expected to be the low-solubility and strongly sorbing Pu(OH4. Depending on the aquifer lithology, the occurrence of reducing conditions along a groundwater flowpath could potentially contribute to the retardation of redox-sensitive radionuclides 99Tc and 237Np, which are commonly identified as long-term dose contributors in the risk assessment in various radionuclide environmental contamination scenarios. The implications for increased sorption of 99Tc and 237Np to devitrified tuff under reducing conditions are significant as the fractured devitrified tuff serves as important water flow path at the NTS and the horizon for a proposed repository to store high-level nuclear waste at Yucca Mountain.

  11. Effect of reducing groundwater on the retardation of redox-sensitive radionuclides

    Science.gov (United States)

    Hu, QH; Zavarin, M; Rose, TP

    2008-01-01

    Laboratory batch sorption experiments were used to investigate variations in the retardation behavior of redox-sensitive radionuclides. Water-rock compositions were designed to simulate subsurface conditions at the Nevada Test Site (NTS), where a suite of radionuclides were deposited as a result of underground nuclear testing. Experimental redox conditions were controlled by varying the oxygen content inside an enclosed glove box and by adding reductants into the testing solutions. Under atmospheric (oxidizing) conditions, radionuclide distribution coefficients varied with the mineralogic composition of the sorbent and the water chemistry. Under reducing conditions, distribution coefficients showed marked increases for 99Tc (from 1.22 at oxidizing to 378 mL/g at mildly reducing conditions) and 237Np (an increase from 4.6 to 930 mL/g) in devitrified tuff, but much smaller variations in alluvium, carbonate rock, and zeolitic tuff. This effect was particularly important for 99Tc, which tends to be mobile under oxidizing conditions. A review of the literature suggests that iodine sorption should decrease under reducing conditions when I- is the predominant species; this was not consistently observed in batch tests. Overall, sorption of U to alluvium, devitrified tuff, and zeolitic tuff under atmospheric conditions was less than in the glove-box tests. However, the mildly reducing conditions achieved here were not likely to result in substantial U(VI) reduction to U(IV). Sorption of Pu was not affected by the decreasing Eh conditions achieved in this study, as the predominant sorbed Pu species in all conditions was expected to be the low-solubility and strongly sorbing Pu(OH)4. Depending on the aquifer lithology, the occurrence of reducing conditions along a groundwater flowpath could potentially contribute to the retardation of redox-sensitive radionuclides 99Tc and 237Np, which are commonly identified as long-term dose contributors in the risk assessment in various radionuclide environmental contamination scenarios. The implications for increased sorption of 99Tc and 237Np to devitrified tuff under reducing conditions are significant as the fractured devitrified tuff serves as important water flow path at the NTS and the horizon for a proposed repository to store high-level nuclear waste at Yucca Mountain. PMID:19077277

  12. Manejo de tiririca e trapoeraba com glyphosate em ambientes sombreados / Commelina benghalensis and Cyperus rotundus treated with glyphosate in shaded environments

    Scientific Electronic Library Online (English)

    A, Santos Júnior; L.D, Tuffi Santos; G.A, Costa; E.A, Barbosa; G.L.D, Leite; V.D, Machado; L.R, Cruz.

    2013-03-01

    Full Text Available Plantas daninhas mantidas em ambientes com redução da intensidade luminosa apresentam alterações morfofisiológicas marcantes, que podem alterar seu comportamento reprodutivo e a tolerância a herbicidas aplicados em pós-emergência. Objetivou-se neste estudo avaliar a eficiência de doses de glyphosate [...] no manejo da trapoeraba (Commelina benghalensis) e da tiririca (Cyperus rotundus) cultivadas em diferentes níveis de sombreamento. O trabalho foi composto por dois ensaios, referentes a cada uma das espécies, com o mesmo delineamento experimental, sendo constituídos em esquema fatorial 5 x 3, com cinco doses de herbicida (0, 540, 810, 1.080 ou 1.350 g ha-1 de glyphosate), três ambientes de cultivo (0, 30 ou 50% de sombra) e quatro repetições. As parcelas experimentais foram compostas por um vaso com duas plantas de tiririca ou de trapoeraba. As avaliações de controle ocorreram aos 10, 20 e 30 dias após a aplicação (DAA), por meio de observações visuais. Aos 30 DAA, foi determinada a massa seca da parte aérea de cada espécie. A produtividade de tubérculos foi observada pela contagem direta desses propágulos presentes nas raízes das plantas de tiririca. Já a sua viabilidade foi avaliada por teste de germinação em leito de areia e por tetrazólio no caso dos não germinados. O controle das espécies foi mais eficiente em ambientes sombreados, contribuindo para a redução de até 25% da dose recomendada para ambas, obtendo-se controle de 81% para trapoeraba e 100% para tiririca. Já a matéria seca da parte aérea, a produtividade e a viabilidade dos tubérculos foram afetadas pelo aumento do nível de sombra e pela dose de glyphosate. A diminuição da intensidade luminosa - comum no sub-bosque de culturas arbóreas e arbustivas ou quando do adensamento de cultivos - representa prática interessante na supressão da trapoeraba e da tiririca e potencializa a ação de controle do glyphosate. Abstract in english Weeds maintained in reduced light intensity environments present remarkable morpho-physiological changes that may alter their reproductive behavior and tolerance to post-emergence herbicides. Our goal was to evaluate the efficiency of glyphosate doses in the management of Commelina benghalensis and [...] Cyperus rotundus grown at different levels of shading. The work consisted of two trials for each species with the same experimental design, in a 5 x 3 factorial design with five herbicide doses (0, 540, 810, 1.080, and 1.350 gha-1 of glyphosate), three cultivation environments (0, 30, or 50% of shading) and four replicates. Experimental plots consisted of a vase with two plants of either C. benghalensis or C. rotundus. Control evaluations were carried out 10, 20, and 30 days after application (DAA) through visual observations. Tuber productivity was verified by direct counting of these propagules present in the roots of C. rotundus plants, while tuber viability was evaluated by germination test in a sand bed, and by tetrazolium, for the non-germinated tubers. Species control was more efficient in shade environments, contributing to a reduction of up to 25% of the recommended dose for the treated species, and resulting in a control of 81% for C. benghalensis and 100% for C. rotundus. Aerial part dry biomass and productivity and viability of tubers were affected by increase in shade level and glyphosate dose. Reduced light intensity - common in the under-story of tree and shrub cultures or in culture density - is an interesting practice aiming at suppressing C. benghalensis and C. rotundus, acting as a potential control of glyphosate.

  13. Controle de plantas daninhas na cultura de soja resistente ao glyphosate Weed control in glyphosate tolerant soybean crop

    OpenAIRE

    Núbia Maria Correia; Julio Cezar Durigan

    2010-01-01

    O objetivo da pesquisa foi avaliar o controle de plantas daninhas em área cultivada com soja resistente ao herbicida glyphosate, sem a utilização de práticas complementares de manejo de plantas daninhas. Foram desenvolvidos experimentos, em condições de campo, nos anos agrícolas 2005/2006 e 2006/2007 em Jaboticabal (SP). Foram avaliadas duas cultivares de soja resistentes ao glyphosate (CD 214 RR e M-SOY 8008 RR), oito tratamentos de herbicidas (glyphosate, em aplicação única, nas doses de 0,...

  14. Intoxicação de espécies de eucalipto submetidas à deriva do glyphosate Intoxication of eucalypt species under glyphosate drift

    OpenAIRE

    Tuffi Santos, L.D.; Ferreira, F.A.; FERREIRA, L. R.; W.M. Duarte; R.A.S. Tiburcio; M.V. Santos

    2006-01-01

    O glyphosate é o herbicida mais utilizado em áreas de reflorestamento de eucalipto. Nessas áreas tem sido freqüente a verificação de sintomas de intoxicação devido à deriva. Entretanto, trabalhos de pesquisa e observações de campo indicam comportamento diferencial entre as espécies e os clones de eucalipto quando em contato com o glyphosate. O presente trabalho teve como objetivo avaliar os efeitos da deriva simulada de glyphosate, por meio de doses reduzidas, no crescimento de cinco espécies...

  15. Translocação do glyphosate em biótipos de azevém (Lolium multiflorum) Glyphosate translocation in Italian ryegrass biotypes (Lolium multiflorum)

    OpenAIRE

    E.A. Ferreira; Santos, J. B.; Silva, A. A.; de Oliveira, J. A.; L. VARGAS

    2006-01-01

    Foram avaliadas neste trabalho a absorção foliar e a translocação do glyphosate por biótipos de azevém (Lolium multiflorum) sensíveis e resistentes a esse herbicida. Para isso, aplicou-se 14C-glyphosate utilizando-se uma microsseringa de precisão, adicionando-se 10 µL da calda sobre a face adaxial da primeira folha com lígula totalmente visível, quando as plantas de azevém se apresentavam com três perfilhos. A quantidade de glyphosate absorvido e translocado foi avaliada em intervalos de temp...

  16. Draft Genome Sequence of Pseudomonas Strain P818, Isolated from Glyphosate-Polluted Soil

    OpenAIRE

    Cao, Gaoyi; Liu, Yunjun; Liu, Guiming; Wang, Jianhua; Wang, Guoying

    2013-01-01

    Pseudomonas strain P818 was isolated from glyphosate-polluted soil in China. This bacterium presents a capacity for high glyphosate tolerance. We present the draft genome sequence of the strain Pseudomonas P818. The genes involved in the glyphosate tolerance were identified. This genomic information will facilitate the study of glyphosate tolerance mechanisms.

  17. Highly sensitive micromachined capacitive pressure sensor with reduced hysteresis and low parasitic capacitance

    DEFF Research Database (Denmark)

    Pedersen, Thomas; Fragiacomo, Giulio

    2009-01-01

    This paper describes the design and fabrication of a capacitive pressure sensor that has a large capacitance signal and a high sensitivity of 76 pF/bar in touch mode operation. Due to the large signal, problems with parasitic capacitances are avoided and hence it is possible to integrate the sensor with a discrete components electronics circuit for signal conditioning. Using an AC bridge electronics circuit a resolution of 8 mV/mbar is achieved. The large signal is obtained due to a novel membrane structure utilizing closely packed hexagonal elements. The sensor is fabricated in a process based on fusion bonding to create vacuum cavities. The exposed part of the sensor is perfectly flat such that it can be coated with corrosion resistant thin films. Hysteresis is an inherent problem in touch mode capacitive pressure sensors and a technique to significantly reduce it is presented.

  18. Reduced baroreflex sensitivity and pulmonary dysfunction in alcoholic cirrhosis: effect of hyperoxia

    DEFF Research Database (Denmark)

    MØller, SØren; Iversen, Jens S

    2010-01-01

    Patients with cirrhosis exhibit impaired regulation of the arterial blood pressure, reduced baroreflex sensitivity (BRS), and prolonged QT interval. In addition, a considerable number of patients have a pulmonary dysfunction with hypoxemia, impaired lung diffusing capacity (Dl(CO)), and presence of hepatopulmonary syndrome (HPS). BRS is reduced at exposure to chronic hypoxia such as during sojourn in high altitudes. In this study, we assessed the relation of BRS to pulmonary dysfunction and cardiovascular characteristics and the effects of hyperoxia. Forty-three patients with cirrhosis and 12 healthy matched controls underwent hemodynamic and pulmonary investigations. BRS was assessed by cross-spectral analysis of variabilities between blood pressure and heart rate time series. A 100% oxygen test was performed with the assessment of arterial oxygen tensions (Pa(O(2))) and alveolar-arterial oxygen gradient. Baseline BRS was significantly reduced in the cirrhotic patients compared with the controls (4.7 +/- 0.8vs. 10.3 +/- 2.0 ms/mmHg; P <0.001). The frequency-corrected QT interval was significantly prolonged in the cirrhotic patients (P <0.05). There was no significant difference in BRS according to presence of HPS, Pa(O(2)), Dl(CO), or Child-Turcotte score, but BRS correlated with metabolic and hemodynamic characteristics. After 100% oxygen inhalation, BRS and the QT interval remained unchanged in the cirrhotic patients. In conclusion, BRS is significantly reduced in patients with cirrhosis compared with controls, but it is unrelated to the degree of pulmonary dysfunction and portal hypertension. Acute hyperoxia does not significantly revert the low BRS or the prolonged QT interval in cirrhosis.

  19. New C$_{6}$D$_{6}$ detectors: reduced neutron sensitivity and improved safety

    CERN Document Server

    Mastinu, Pierfrancesco; Berthoumieux, Eric; Cano-Ott, Daniel; Gramegna, F; Guerrero, Carlos; Massimi, Cristian; Milazzo, Paolo Maria; Mingrone, Federica; Praena, Javier; Prete, G; García, Aczel Regino

    2013-01-01

    During the 2011 data measurement campaign at n_TOF, the liquid scintillator detectors developed at FZK-Karlsruhe (hereafter named K6D6, [1]) and used with success along 10 years have shown ageing problems, mainly related to liquid leakage. The mould used to produce the carbon fiber structure, containing the liquid and the detection elements, was not available anymore and the technician involved in its construction was retired. Once decided to proceed to the production of new detectors (L6D6 in the following) two major items have been identified: - The detector setup must be able to work in the new class A experimental area (safety requirements advise to avoid the use of the old K6D6 in this area). - If possible, it is useful to reduce the neutron sensitivity, with the aim to have a liquid scintillator detector with very low neutron sensitivity (improving the already high performing K6D6). [1] R.Plag et al., NIM A496 (2003) 425

  20. Enthalpic partitioning of the reduced temperature sensitivity of O2 binding in bovine hemoglobin

    DEFF Research Database (Denmark)

    Weber, Roy E; Fago, Angela

    2014-01-01

    The oxygenation enthalpy of the heme groups of hemoglobin (Hb) is inherently exothermic, resulting in decreased Hb-O2 affinity with rising temperature. However, oxygenation is coupled with endothermic dissociation of allosteric effectors (e.g. protons, chloride ions and organic phosphates) from the protein moiety, which thus reduces the overall oxygenation enthalpy. The evolution of Hbs with reduced temperature sensitivity ostensibly safeguards O2 unloading in cold extremities of regionally-heterothermic vertebrates permitting energy-saving reductions in heat loss. Ungulate (e.g. bovine) Hbs have long served as a model system in this regard in that they exhibit numerically low oxygenation enthalpies that are thought to correlate with the presence of an additional Cl(-) binding site (compared to human Hb) comprised of three cationic residues at positions 8, 76 and 77 of the ?-chains of Hb. However, ungulate Hbs also exhibit distinctive amino acid exchanges at the N-termini of the ?-chains that stabilize the low-affinity deoxystructure of the Hb, mimicking the action of organic phosphates. In order to assess the relative contributions from these two effects, we measured the temperature sensitivity of Hb-O2 affinity in bovine and human Hbs in the absence and presence of Cl(-) ions under strictly controlled pH conditions. The data indicate that Cl(-)-binding accounts for a minority (~30%) of the total reduction in the oxygenation enthalpy manifested in bovine compared to human Hb, whereas the majority of this reduction is ascribable to structural differences, including increased ?-chain hydrophobicity that would increase the heat of oxygenation-linked conformational change in bovine Hb.

  1. Metallic complexes with glyphosate: a review

    International Nuclear Information System (INIS)

    We present studies involving metallic ions and the herbicide glyphosate. The metallic complexes of Cu(II), Zn(II), Mn(II), Ni(II), Cd(II), Pb(II), Cr(III), Fe(III), Co(III), ammonium, sodium, Ag(I), alkaline earth metals and of some lanthanides ions are described. The complexes are discussed in terms of their synthesis, identification, stability and structural properties, based on data from the current literature. (author)

  2. Synthesis of 15N labeled glyphosate

    International Nuclear Information System (INIS)

    Amongst the actually commercialized herbicides the Glyphosate is the most used in Brazil. Its efficiency as well as the others herbicides against undesirable weeds is harmed by its final composts left at the environment. Although studies has being carried out to improve the knowledge about the herbicides behavior at the environment its complexity has led them towards innumerous to new significant research work where the use of radiolabeled composts (radiative tracers) are recommended to evaluate their bio-availability in the soil. However is the use, the manipulation and the storage of radiolabeled composts is requires an extra care under chemical safety point of view. The use of non radiolabeled composts is a world tendency especially for field researches. Under this context the presented work describes a method for the synthesis of 15N labeled glyphosate. The 15N-herbicide was undertaken by phosphometilation with the phosphit dialquil and 15N-glycine. The tests where carried out through a micro scale production plant and of equimolars amounts. At these conditions it's was possible to reach approximately a 20% of yield. At the conclusion of a best operational condition its expected to offer another important toll that shall be used in glyphosate behavior at the environment and undesirably weeds. (author)

  3. Reducing the effect of respiration in baroreflex sensitivity estimation with adaptive filtering.

    Science.gov (United States)

    Tiinanen, Suvi; Tulppo, Mikko; Seppänen, Tapio

    2008-01-01

    Cardiac baroreflex is described by baroreflex sensitivity (BRS) from blood pressure and heart rate interval (RRi) fluctuations. However, respiration affects both blood pressure and RRi via mechanisms that are not necessarily of baroreflex origin. To separate the effects of baroreflex and respiration, metronome-guided breathing in a high frequency band (HF, 0.25-0.4 Hz) and a low frequency spectral band (LF, 0.04-0.15 Hz) have therefore been commonly used for BRS estimation. The controlled breathing may, however, change the natural functioning of the autonomic system and interfere BRS estimates. To enable usage of spontaneous breathing, we propose an adaptive LMS-based filter for removing the respiration effect from the BRS estimates. ECG, continuous blood pressure and respiration were measured during 5 min spontaneous and 5 min controlled breathing at 0.25 Hz in healthy males (n = 24, 33+/-7 years). BRS was calculated with spectral methods from the LF band with and without filtering. In those subjects whose spontaneous breathing rate was adaptive filtering reduced the bias significantly. As a conclusion, the adaptive filter reduces the distorting effect of respiration on BRS values, which enables more accurate estimation of BRS and the usage of spontaneous breathing as a measurement protocol. PMID:18232346

  4. High-sensitive C-reactive protein is associated with reduced lung function in young adults

    DEFF Research Database (Denmark)

    Rasmussen, F; Mikkelsen, D

    2009-01-01

    Systemic inflammation has been associated with reduced lung function. However, data on the interrelationships between lung function and inflammation are sparse, and it is not clear if low-grade inflammation leads to reduced lung function. Associations between high-sensitive C-reactive protein (CRP) and spirometric lung function were assessed in a population-based cohort of approximately 1,000 Danes aged 20 yrs. In males, the average decline in forced expiratory volume in one second (FEV(1)) in the highest CRP quintile was 23 mL.yr(-1) versus 1.6 mL.yr(-1) in the lowest quintile. In females, the average decline was 6.2 mL.yr(-1) in the highest CRP quintile versus an increase of 1.8 mL.yr(-1) in the lowest CRP quintile. In a multiple regression analysis adjusted for sex, body mass index, cardiorespiratory fitness, smoking, asthma, airway hyperresponsiveness and serum eosinophil cationic protein, higher levels of CRP at age 20 yrs were associated with a greater reduction in both FEV(1) and forced vital capacity between ages 20 and 29 yrs. The findings show that higher levels of C-reactive protein in young adults are associated with subsequent decline in lung function, suggesting that low-grade systemic inflammation in young adulthood may lead to impaired lung function independently of the effects of smoking, obesity, cardiorespiratory fitness, asthma and eosinophilic inflammation.

  5. Biological response of soybean and cotton to aerial glyphosate drift

    Science.gov (United States)

    An aerial application drift study was conducted in 2009 to determine biological effects of glyphosate on cotton (Gossypium hirsutum L.) and soybean [Glycine max (L.) Merr.]. Glyphosate at 866 g ae/ha was applied using an Air Tractor 402B agricultural aircraft in an 18.3 m spray swath to crops at the...

  6. Heterodera glycines Population Development on Soybean Treated with Glyphosate

    Science.gov (United States)

    Soybean cyst nematode (Heterodera glycines) is a major yield limiting pest in all major soybean producing countries. In the last decade genetically modified soybean tolerant to glyphosate has become widely planted and postemergence application of glyphosate has increased exponentially. Genetically m...

  7. Glyphosate effects on soil rhizosphere-associated bacterial communities.

    Science.gov (United States)

    Newman, Molli M; Hoilett, Nigel; Lorenz, Nicola; Dick, Richard P; Liles, Mark R; Ramsier, Cliff; Kloepper, Joseph W

    2016-02-01

    Glyphosate is one of the most widely used herbicides in agriculture with predictions that 1.35millionmetric tons will be used annually by 2017. With the advent of glyphosate tolerant (GT) cropping more than 10years ago, there is now concern for non-target effects on soil microbial communities that has potential to negatively affect soil functions, plant health, and crop productivity. Although extensive research has been done on short-term response to glyphosate, relatively little information is available on long-term effects. Therefore, the overall objective was to investigate shifts in the rhizosphere bacterial community following long-term glyphosate application on GT corn and soybean in the greenhouse. In this study, rhizosphere soil was sampled from rhizoboxes following 4 growth periods, and bacterial community composition was compared between glyphosate treated and untreated rhizospheres using next-generation barcoded sequencing. In the presence or absence of glyphosate, corn and soybean rhizospheres were dominated by members of the phyla Proteobacteria, Acidobacteria, and Actinobacteria. Proteobacteria (particularly gammaproteobacteria) increased in relative abundance for both crops following glyphosate exposure, and the relative abundance of Acidobacteria decreased in response to glyphosate exposure. Given that some members of the Acidobacteria are involved in biogeochemical processes, a decrease in their abundance could lead to significant changes in nutrient status of the rhizosphere. Our results also highlight the need for applying culture-independent approaches in studying the effects of pesticides on the soil and rhizosphere microbial community. PMID:26580738

  8. Glyphosate Applied at Low Doses Can Stimulate Plant Growth

    Science.gov (United States)

    Glyphosate blocks the shikimic acid pathway, inhibiting the production of aromatic amino acids and several secondary compounds derived from these amino acids. Non-target plants can be exposed to low doses of glyphosate by herbicide drift of spray droplets and contact with treated weeds. Previous s...

  9. Research on the weed control degree and glyphosate soil biodegradation in apple plantations (Pioneer variety)

    OpenAIRE

    Ersilia ALEXA; Roxana MICU; Monica NEGREA; Renata SUMALAN; Olimpia IORDANESCU

    2010-01-01

    In this study we follow control degree of glyphosate herbicide on weeds in apple plantations (Pioneer variety) of the Research Station Timisoara. It was also followed glyphosate biodegradation capacity in the soil by determining the amount of CO2 released by the action of microorganisms on C14 glyphosate marked isotope. Laboratory analysis of glyphosate residues in soil was made using a Liquid Scintillation TRIATHLER. Glyphosate biodegradation ability in the presence of soil microorganisms is...

  10. Glyphosate tolerance of soybean mutant gained after boarding on satellite

    International Nuclear Information System (INIS)

    Glyphosate-tolerant germplasm and genetic variation characteristics of SP2 and SP3 soybean varieties boarded on Shijian No.8 satellite were analyzed after treated by herbicide glyphosate in the field. Abundant variations of traits were produced, and the resistance within and among cultivars were different in their offspring of space mutagenesis. Plant height and maturity were used as index to screen glyphosate tolerant materials. Space mutation increased of soybean 661 SP3 of Zhongpin, and one glyphosate-resistance variant was screened from Zhongpin 661 SP3. It showed that glyphosate tolerance was different among offspring of different space mutagenesis soybean materials. It is feasible to systemically screen elite traits soybean by applying space mutation breeding. (authors)

  11. DISPERSION OF GLYPHOSATE IN SOILS UNDERGOING EROSION

    Directory of Open Access Journals (Sweden)

    Gorana Todorovic Rampazzo

    2010-08-01

    Full Text Available Different physical, chemical and biological processes influence the behaviour of organic contaminants in soils. A better understanding of the organic pollutant behaviour in soils would improve the environmental protection. One possible way for better attenuation of the risk of pollution in agriculture can be achieved through ta better-specified pesticide management based on the adaptation of the pesticide type and application rates to the specific environmental characteristics of the area of application. Nowadays, one of the actually most applied herbicide world wide is glyphosate. Glyphosate is highly water soluble and traces have been found in surface and groundwater systems. For a better understanding of the natural influence of erosion processes on glyphosate behaviour and dispersion under heavy rain conditions after application in the field, two erosion simulation experiments were conducted on two different locations in Austria with completely different soil types in September 2008. The results of the experiments showed that under normal practical conditions (e.g. no rainfall is expected immediatly after application, the potential adsorption capacity of the Kirchberg soil (Stagnic Cambisol, with about 16.000 ppm Fe-oxides is confirmed compared to the low adsorption Chernosem soil (about 8.000 ppm pedogenic Fe-oxides.  Considering the enormous difference in the run-off amounts between the two sites Pixendorf and Kirchberg soils it can be concluded how important the soil structural conditions and vegetation type and cover are for the risks of erosion and, as a consequence, pollution of neighbouring waters. In the rainfall experiments under comparable simulation conditions, the amount of run-off was about 10 times higher at Kirchberg, owing to its better infiltration rate, than at the Pixendorf site. Moreover, the total loss of glyphosate (NT+CT through run-off at the Kirchberg site was more than double that at Pixendorf, which confirms the importance of the chemical and mineralogical nature of soils in the abatement and absorbency of glyphosate, and the poor results in case of erosive precipitations whwn soil structure and permeability are not favourable.

  12. Effect of Glyphosate-boron Application on Seed Composition and Nitrogen Metabolism in Glyphosate-resistant Soybean

    Science.gov (United States)

    Information is limited on the effect of combined foliar application of glyphosate (Gly) and boron (B) on seed composition and nitrogen metabolism in glyphosate resistant soybean (Glycine max(L.)Merr.). Therefore, the objective of this two-year field study was to evaluate the effects of single foliar...

  13. Surface modifications of photoanodes in dye sensitized solar cells: enhanced light harvesting and reduced recombination

    Science.gov (United States)

    Saxena, Vibha; Aswal, D. K.

    2015-06-01

    In a quest to harvest solar power, dye-sensitized solar cells (DSSCs) have potential for low-cost eco-friendly photovoltaic devices. The major processes which govern the efficiency of a DSSC are photoelectron generation, injection of photo-generated electrons to the conduction band (CB) of the mesoporous nanocrystalline semiconductor (nc-SC); transport of CB electrons through nc-SC and subsequent collection of CB electrons at the counter electrode (CE) through the external circuit; and dye regeneration by redox couple or hole transport layer (HTL). Most of these processes occur at various interfaces of the photoanode. In addition, recombination losses of photo-generated electrons with either dye or redox molecules take place at the interfaces. Therefore, one of the key requirements for high efficiency is to improve light harvesting of the photoanode and to reduce the recombination losses at various interfaces. In this direction, surface modification of the photoanode is the simplest method among the various other approaches available in the literature. In this review, we present a comprehensive discussion on surface modification of the photoanode, which has been adopted in the literature for not only enhancing light harvesting but also reducing recombination. Various approaches towards surface modification of the photoanode discussed are (i) fluorine-doped tin oxide (FTO)/nc-SC interface modified via a compact layer of semiconductor material which blocks exposed sites of FTO to electrolyte (or HTL), (ii) nc-SC/dye interface modification either through acid treatment resulting in enhanced dye loading due to a positively charged surface or by depositing insulating/semiconducting blocking layer on the nc-SC surface, which acts as a tunneling barrier for recombination, (iii) nc-SC/dye interface modified by employing co-adsorbents which helps in reducing the dye aggregation and thereby recombination, and (iv) dye/electrolyte (or dye/HTL) interface modification using additives which provides surface passivation as well as positive movement of the nc-SC Fermi level owing to negative charge at the surface and hence improves light harvesting and reduced recombination. Finally, we discuss the advantages and disadvantages of various approaches towards high-efficiency DSSCs.

  14. Uso de aminoácido exógeno na prevenção de injúrias causadas por glyphosate na soja RR / Use of exogenous amino acid to prevent glyphosate injury in glyphosate-resistant soybean

    Scientific Electronic Library Online (English)

    L.H.S., Zobiole; R.S., Oliveira Jr.; J., Constantin; D.F., Biffe; R.J., Kremer.

    Full Text Available O aumento da área cultivada de soja resistente ao glyphosate (RR) no Brasil é resultado do benefício dessa tecnologia no manejo de plantas daninhas. No entanto, a expansão da área de soja RR aumentou significativamente o uso de glyphosate e consequentemente, em alguns casos, têm sido observados sint [...] omas de injúrias na soja RR conhecidos como yellow flashing ou amarelecimento das folhas superiores. Nesse sentido, dois experimentos, em diferentes anos, foram conduzidos em delineamento inteiramente casualizado, com quatro repetições. O primeiro teve o objetivo de avaliar a influência do glyphosate na soja RR nas variáveis fotossintéticas, nos parâmetros de nodulação e na biomassa seca da parte aérea e raiz, realizando-se a comparação entre os tratamentos BRS 242 RR sem glyphosate, BRS 242 RR + glyphosate e a isolinha parental não-RR cv. Embrapa 58, submetidas a uma dose de glyphosate de 1.200 g e.a. ha-1; aplicada no estádio V4. O segundo experimento foi conduzido visando reavaliar as variáveis fotossintéticas, de produção de biomassa e nodulação afetadas na soja RR pelo glyphosate no primeiro experimento. Entretanto, no segundo experimento foi avaliada a utilização de diversas modalidades de aplicação de aminoácidos (a.a.), sendo os diferentes tratamentos (sem a.a.; tratamento de semente com a.a; tratamento de semente com a.a. + aplicação foliar de a.a.; sem tratamento de sementes com a.a; e com aplicação foliar de a.a) combinados com diferentes doses de glyphosate (1.200 e 2.400 g e.a. ha-1), objetivando uma provável recuperação das plantas de soja com sua utilização exógena. Em ambos os experimentos, as variáveis fotossintéticas, os parâmetros de nodulação e biomassa seca da parte aérea e raiz foram afetados pela aplicação do glyphosate, porém o segundo experimento evidenciou, de modo geral, que o uso de aminoácidos via tratamento de sementes associado com aplicação foliar pode ser uma estratégia para prevenir os efeitos indesejáveis desse herbicida na cultura da soja RR. Abstract in english Cultivation of glyphosate-resistant (GR) soybeans has increased in Brazil as a result of the application of this technology in weed management systems developed for this crop. However, the expansion of GR soybean production has significantly increased the use of glyphosate and, in some cases, result [...] ed in injury symptoms observed in GR soybean, known as "yellow flashing" or yellowing of the upper leaves. Thus, two experiments were conducted in different years. The first experiment aimed to evaluate the influence of glyphosate on GR soybeans regarding the photosynthetic variables, nodule parameters, and shoot and root dry biomass by comparing cultivar BRS 242 GR without glyphosate and BRS 242 RR + glyphosate at 1.200 g ha-1 at V4 growth stage, to the near isogenic non-GR parental line cv. Embrapa 58. The second experiment aimed to reassess the same parameters in GR soybeans at the V4 stage treated with glyphosate, plus the application of various amino acids, to evaluate the expected recovery of soybean growth under the exogenous use of supplemental amino acids. In general, the photosynthetic variables, nodulation parameters and shoot and root dry biomass were affected by glyphosate; however, the use of amino acids may be a strategy to prevent the undesirable effects of this herbicide on GR soybean

  15. Central fuel banking to reduce the number of proliferation sensitive enrichment activities

    International Nuclear Information System (INIS)

    Central fuel banking is a complex international political, economic and technical concept that aims to reduce uncontrolled spreading of uranium enrichment technology in the world in order to prevent proliferation of nuclear weapons. This paper first gives an outline of the notions: 'non-proliferation', the 'front-end' of the fuel cycle, the scope of fuel baking, nuclear fuel and the 60 years of enrichment technology. Enrichment technology is highly concentrated in the nuclear weapon states and other developed countries, but this is not exclusive any more. The technology is spreading. The global demand for enrichment services - parallel to massive nuclear investments in the civil sector and the ageing of older facilities - is constantly growing. Proliferation sensitivity calls for an effective and comprehensive non-proliferation regime. The solution may be multilateralizing the nuclear fuel cycle. After a historical overview, the proposals on multilateral nuclear approaches are presented. The assessment of the proposals is complex in the dimensions of: the non-proliferation aim, the assurance of supply aspect and other variables such as legal issues and non-nuclear inducements. A general evaluation and the recommendations of the Expert Panel of the IAEA are introduced outlining a plan on a middle- and long-term basis. The conclusion of the paper stresses the importance and challenge in finding the 'new balance' between obligations and interests of the members of the global community stating that the answers will have a significant impact on the nuclear indus- try, world wide economics and security policy. (orig.)

  16. Detonation and Shock Reactivity Properties of Explosives Containing RDX and Reduced Sensitivity RDX

    Science.gov (United States)

    Sutherland, Gerrit

    2005-07-01

    The detonation and shock reactivity properties of two monomodal research explosives were measured to assess how these properties change when different quality RDX is used. One explosive contained class 1 (coarse) RDX and HTPB binder; the other explosive contained reduced sensitivity (high quality) class 1 RDX (I-RDX) and HTPB binder. Experiments preformed included wave curvature, rate stick and flyer plate experiments. Wave curvature and rate stick experiments indicate that the reaction zone length is shorter for the explosive containing RDX. Our results show that decrement and wave curvature results are bounded by the results of Moulard and coworkers^1,2 for similar explosives containing fine and very coarse RDX particles. We will also present work of ongoing shock reactivity experiments. In these experiments, a flyer impacts an explosive sample containing multiple embedded pressure gauges. Analyses of the pressure gauge records allow us to determine shock reactivity trends for each explosive. ^1Moulard, H., Kury, J.W., Delclos, A., Proceedings of Eighth Symposium (International) on Detonation, Albuquerque, NM, 1985, pg. 902-913. ^2 Moulard, H., Proceedings of the Ninth Symposium (International) on Detonation, Portland, Oregon, 1989, pg. 18-24.

  17. Seeking Energy System Pathways to Reduce Ozone Damage to Ecosystems through Adjoint-based Sensitivity Analysis

    Science.gov (United States)

    Capps, S. L.; Pinder, R. W.; Loughlin, D. H.; Bash, J. O.; Turner, M. D.; Henze, D. K.; Percell, P.; Zhao, S.; Russell, M. G.; Hakami, A.

    2014-12-01

    Tropospheric ozone (O3) affects the productivity of ecosystems in addition to degrading human health. Concentrations of this pollutant are significantly influenced by precursor gas emissions, many of which emanate from energy production and use processes. Energy system optimization models could inform policy decisions that are intended to reduce these harmful effects if the contribution of precursor gas emissions to human health and ecosystem degradation could be elucidated. Nevertheless, determining the degree to which precursor gas emissions harm ecosystems and human health is challenging because of the photochemical production of ozone and the distinct mechanisms by which ozone causes harm to different crops, tree species, and humans. Here, the adjoint of a regional chemical transport model is employed to efficiently calculate the relative influences of ozone precursor gas emissions on ecosystem and human health degradation, which informs an energy system optimization. Specifically, for the summer of 2007 the Community Multiscale Air Quality (CMAQ) model adjoint is used to calculate the location- and sector-specific influences of precursor gas emissions on potential productivity losses for the major crops and sensitive tree species as well as human mortality attributable to chronic ozone exposure in the continental U.S. The atmospheric concentrations are evaluated with 12-km horizontal resolution with crop production and timber biomass data gridded similarly. These location-specific factors inform the energy production and use technologies selected in the MARKet ALlocation (MARKAL) model.

  18. Highly sensitive reduced graphene oxide impedance sensor harnessing ?-stacking interaction mediated direct deposition of protein probes.

    Science.gov (United States)

    Kim, Kwang Su; Um, Yu Mi; Jang, Ji-Ryang; Choe, Woo-Seok; Yoo, Pil J

    2013-05-01

    Graphene-based electrochemical impedance sensors have recently received much attention due to their outstanding sensing capability and economic viability. In this study, we present a novel means of constructing an impedance sensing platform via harnessing intrinsic ?-stacking interactions between probe protein molecules and reduced graphene oxide (RGO) substrate, obviating the need for introducing external chemical groups often required for covalent anchoring of the probes. To achieve this goal, protein molecules used as a probe were denatured to render their hydrophobic residues exposed in order to facilitate their direct ?-stacking interactions with the surface of RGO nanosheets. The protein molecules in denatured form, which would otherwise have difficulty in undergoing ?-stacking interactions with the RGO surface, were found to uniformly cover the RGO nanosheets at high density, conducive to providing a graphene-based impedance sensing platform capable of detecting a probe-specific analyte at high sensitivity. The proof-of-concept performance of thus-constructed RGO-based impedance sensors was demonstrated via selective detection of biological binding events of antigen-antibody reaction at a femtomolar range. Notably, since the ?-stacking interaction can occur on the entire RGO surface, it can desirably exclude a backfill process indispensable for the conventional biosensors to suppress background noise signals. Since the procedure of ?-stacking mediated direct deposition of on-purpose denatured protein probes onto the RGO surface is facile and straightforward, the proposed strategy is anticipated to extend its applicability for fabrication of high performance graphene-based bio or chemical sensors. PMID:23551147

  19. The occurrence of glyphosate, atrazine, and other pesticides in vernal pools and adjacent streams in Washington, DC, Maryland, Iowa, and Wyoming, 2005-2006

    Science.gov (United States)

    Battaglin, W.A.; Rice, K.C.; Focazio, M.J.; Salmons, S.; Barry, R.X.

    2009-01-01

    Vernal pools are sensitive environments that provide critical habitat for many species, including amphibians. These small water bodies are not always protected by pesticide label requirements for no-spray buffer zones, and the occurrence of pesticides in them is poorly documented. In this study, we investigated the occurrence of glyphosate, its primary degradation product aminomethylphosphonic acid, and additional pesticides in vernal pools and adjacent flowing waters. Most sampling sites were chosen to be in areas where glyphosate was being used either in production agriculture or for nonindigenous plant control. The four site locations were in otherwise protected areas (e.g., in a National Park). When possible, water samples were collected both before and after glyphosate application in 2005 and 2006. Twenty-eight pesticides or pesticide degradation products were detected in the study, and as many as 11 were identified in individual samples. Atrazine was detected most frequently and concentrations exceeded the freshwater aquatic life standard of 1.8 micrograms per liter (??g/l) in samples from Rands Ditch and Browns Ditch in DeSoto National Wildlife Refuge. Glyphosate was measured at the highest concentration (328 ??g/l) in a sample from Riley Spring Pond in Rock Creek National Park. This concentration exceeded the freshwater aquatic life standard for glyphosate of 65 ??g/l. Aminomethylphosphonic acid, triclopyr, and nicosulfuron also were detected at concentrations greater than 3.0 ??g/l. ?? Springer Science+Business Media B.V. 2008.

  20. Uso de aminoácido exógeno na prevenção de injúrias causadas por glyphosate na soja RR Use of exogenous amino acid to prevent glyphosate injury in glyphosate-resistant soybean

    OpenAIRE

    L.H.S. Zobiole; R.S. Oliveira JR; J. Constantin; D.F Biffe; R.J. Kremer

    2010-01-01

    O aumento da área cultivada de soja resistente ao glyphosate (RR) no Brasil é resultado do benefício dessa tecnologia no manejo de plantas daninhas. No entanto, a expansão da área de soja RR aumentou significativamente o uso de glyphosate e consequentemente, em alguns casos, têm sido observados sintomas de injúrias na soja RR conhecidos como yellow flashing ou amarelecimento das folhas superiores. Nesse sentido, dois experimentos, em diferentes anos, foram conduzidos em delineamento inteirame...

  1. Glyphosate herbicide induces genotoxic effect and physiological disturbances in Bulinus truncatus snails.

    Science.gov (United States)

    Bakry, Fayez A; Ismail, Somaya M; Abd El-Atti, Mahmoud S

    2015-09-01

    Herbicides are being used in agriculture for controlling noxious weed. Glyphosate is a herbicide that is widely applied to cereal crops in Egypt and is used in controlling a very broad spectrum of weeds. The present study was designed to investigate the response of the snail Bulinus truncatus as a bioindicator for physiological and molecular aspects of B.?truncatus snails after exposure to sublethal concentrations of glyphosate for two weeks. In treating snails, glucose concentration (GL) in the haemolymph as well as lactate (LT) in soft tissues of treated snails increased, while glycogen (GN), pyruvate (PV), total protein (TP), nucleic acids (DNA and RNA) levels in snail's tissues decreased. The activities of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR), thioredoxin reductase (TrxR), glycogen phosphorylase (GP), glucose-6-phosphatase (G-6-Pase), succinic dehydrogenase (SDH) and lactic dehydrogenase (LDH) enzymes in homogenate of snail's tissues were reduced in response to the treatment with the herbicide, while lipid peroxide (LP), sorbitol dehydrogenase (SDH) and transaminases (GOT and GPT) activity increased (P?glyphosate herbicide may be attributed to the fact that the herbicide can induce genotoxicity through DNA damage. Thus, the present result indicated that the genotoxicity products at low concentration and for long time treatment showed the hazard of herbicide addiction on man's life. PMID:26267049

  2. Glyphosate, pathways to modern diseases III: Manganese, neurological diseases, and associated pathologies.

    Science.gov (United States)

    Samsel, Anthony; Seneff, Stephanie

    2015-01-01

    Manganese (Mn) is an often overlooked but important nutrient, required in small amounts for multiple essential functions in the body. A recent study on cows fed genetically modified Roundup(®)-Ready feed revealed a severe depletion of serum Mn. Glyphosate, the active ingredient in Roundup(®), has also been shown to severely deplete Mn levels in plants. Here, we investigate the impact of Mn on physiology, and its association with gut dysbiosis as well as neuropathologies such as autism, Alzheimer's disease (AD), depression, anxiety syndrome, Parkinson's disease (PD), and prion diseases. Glutamate overexpression in the brain in association with autism, AD, and other neurological diseases can be explained by Mn deficiency. Mn superoxide dismutase protects mitochondria from oxidative damage, and mitochondrial dysfunction is a key feature of autism and Alzheimer's. Chondroitin sulfate synthesis depends on Mn, and its deficiency leads to osteoporosis and osteomalacia. Lactobacillus, depleted in autism, depend critically on Mn for antioxidant protection. Lactobacillus probiotics can treat anxiety, which is a comorbidity of autism and chronic fatigue syndrome. Reduced gut Lactobacillus leads to overgrowth of the pathogen, Salmonella, which is resistant to glyphosate toxicity, and Mn plays a role here as well. Sperm motility depends on Mn, and this may partially explain increased rates of infertility and birth defects. We further reason that, under conditions of adequate Mn in the diet, glyphosate, through its disruption of bile acid homeostasis, ironically promotes toxic accumulation of Mn in the brainstem, leading to conditions such as PD and prion diseases. PMID:25883837

  3. Utilização de glifosato para o controle de ferrugem da soja Glyphosate application on soybean rust control

    Directory of Open Access Journals (Sweden)

    Rafael Moreira Soares

    2008-04-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de glifosato sobre a germinação de esporos de Phakopsora pachyrhizi e no controle da ferrugem da soja, aplicado preventiva e erradicativamente, em condições controladas. A germinação de esporos foi avaliada tendo-se vertido, em meio de cultura, soluções de esporos com diferentes concentrações do glifosato (0, 100, 1.000, 10.000 e 20.000 ppm e fungicidas. Para avaliar o controle da ferrugem, plantas foram pulverizadas com glifosato, com variação da dose e do momento, tendo-se medido a severidade da doença. Houve efeito do produto sobre os esporos do fungo, o que reduziu sua germinação. As pulverizações em plantas, em casa de vegetação, mostraram um efeito do produto sobre a ferrugem, quando aplicado preventivamente, porém com período de proteção curto e fungitoxicidade inferior à do fungicida tebuconazole. O uso do glifosato, avaliado nesse ensaio, não deve ser visto como medida de manejo de ferrugem, e não interfere nas práticas habituais de controle da ferrugem da soja.The objective of this work was to evaluate the effect of glyphosate on the germination of Phakopsora pachyrhizi spores, and on soybean rust control; applications were either preventive or eradicative under controlled conditions. The germination of spores was evaluated by pouring spores solutions on culture medium, with different concentrations of glyphosate (0, 100, 1,000, 10,000 and 20,000 ppm and fungicides. For the rust control evaluation, plants were sprayed with glyphosate, varying doses and moments, and estimating the disease severity. The product reduced spores germination. Plants sprayed in greenhouse conditions, showed effect of the product on rust, when applied preventively, but with short protection period and lower fungus toxicity than tebuconazole fungicide. The use of glyphosate, evaluated in this trial, must not be taken as a rust management measure, and should not interfere in usual practices for soybean rust control.

  4. Utilização de glifosato para o controle de ferrugem da soja / Glyphosate application on soybean rust control

    Scientific Electronic Library Online (English)

    Rafael Moreira, Soares; Dionísio Luiz Pisa, Gazziero; Daniela Alves dos Santos, Morita; Mônica Lúcia, Ciliato; Allan Misael, Flausino; Leandro Cezar Menezes, Santos; Tatiani, Janegitz.

    2008-04-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito de glifosato sobre a germinação de esporos de Phakopsora pachyrhizi e no controle da ferrugem da soja, aplicado preventiva e erradicativamente, em condições controladas. A germinação de esporos foi avaliada tendo-se vertido, em meio de cultura, soluções [...] de esporos com diferentes concentrações do glifosato (0, 100, 1.000, 10.000 e 20.000 ppm) e fungicidas. Para avaliar o controle da ferrugem, plantas foram pulverizadas com glifosato, com variação da dose e do momento, tendo-se medido a severidade da doença. Houve efeito do produto sobre os esporos do fungo, o que reduziu sua germinação. As pulverizações em plantas, em casa de vegetação, mostraram um efeito do produto sobre a ferrugem, quando aplicado preventivamente, porém com período de proteção curto e fungitoxicidade inferior à do fungicida tebuconazole. O uso do glifosato, avaliado nesse ensaio, não deve ser visto como medida de manejo de ferrugem, e não interfere nas práticas habituais de controle da ferrugem da soja. Abstract in english The objective of this work was to evaluate the effect of glyphosate on the germination of Phakopsora pachyrhizi spores, and on soybean rust control; applications were either preventive or eradicative under controlled conditions. The germination of spores was evaluated by pouring spores solutions on [...] culture medium, with different concentrations of glyphosate (0, 100, 1,000, 10,000 and 20,000 ppm) and fungicides. For the rust control evaluation, plants were sprayed with glyphosate, varying doses and moments, and estimating the disease severity. The product reduced spores germination. Plants sprayed in greenhouse conditions, showed effect of the product on rust, when applied preventively, but with short protection period and lower fungus toxicity than tebuconazole fungicide. The use of glyphosate, evaluated in this trial, must not be taken as a rust management measure, and should not interfere in usual practices for soybean rust control.

  5. Effects of pig slurry application on soil physical and chemical properties and glyphosate mobility

    Directory of Open Access Journals (Sweden)

    Daniela Aparecida de Oliveira

    2014-10-01

    Full Text Available Pig slurry applied to soil at different rates may affect soil properties and the mobility of chemical compounds within the soil. The purpose of this study was to evaluate the effects of rates of pig slurry application in agricultural areas on soil physical and chemical properties and on the mobility of glyphosate through the soil profile. The study was carried out in the 12th year of an experiment with pig slurry applied at rates of 0 (control, 50, 100 and 200 m³ ha-1 yr-1 on a Latossolo Vermelho distrófico (Hapludox soil. In the control, the quantities of P and K removed by harvested grains were replaced in the next crop cycle. Soil physical properties (bulk density, porosity, texture, and saturated hydraulic conductivity and chemical properties (organic matter, pH, extractable P, and exchangeable K were measured. Soil solution samples were collected at depths of 20, 40 and 80 cm using suction lysimeters, and glyphosate concentrations were measured over a 60-day period after slurry application. Soil physical and chemical properties were little affected by the pig slurry applications, but soil pH was reduced and P levels increased in the surface layers. In turn, K levels were increased in sub-surface layers. Glyphosate concentrations tended to decrease over time but were not affected by pig slurry application. The concentrations of glyphosate found in different depths show that the pratice of this application in agricultural soils has the potential for contamination of groundwater, especially when the water table is the surface and heavy rains occur immediately after application.

  6. Glyphosate em mistura com herbicidas alternativos para o manejo de plantas daninhas Glyphosate combined with alternative herbicides for vegetation management

    Directory of Open Access Journals (Sweden)

    P.A. Monquero

    2001-12-01

    Full Text Available O uso intensivo de glyphosate como herbicida não-seletivo tem selecionado espécies de plantas daninhas tolerantes. Dessa forma, é importante que sejam estudadas misturas de tanque com herbicidas de mecanismos de ação alternativos e que apresentem efeitos sinergísticos ou aditivos. Por essa razão, foi instalado um experimento inteiramente casualizado, composto por 13 tratamentos e 4 repetições, em casa de vegetação da Universidade de São Paulo - ESALQ/USP, Piracicaba-SP, com as plantas daninhas Richardia brasiliensis, Commelina benghalensis, Amaranthus hybridus, Galinsoga parviflora e Ipomoea grandifolia em misturas de tanque dos herbicidas chlorimuron-ethyl, sulfentrazone, carfentrazone, bentazon ou flumioxazin com glyphosate. As interações foram aditivas para as plantas daninhas I. grandifolia e C. benghalensis, e os herbicidas flumioxazin, sulfentrazone e carfentrazone aplicados isoladamente e em mistura com glyphosate foram os que proporcionaram os melhores níveis de controle. A interação de glyphosate com sulfentrazone foi antagônica em R. brasiliensis; a mistura de glyphosate com os demais herbicidas estudados foi aditiva, sendo os tratamentos com mistura de glyphosate e chlorimuron-ethyl ou flumioxazin os mais eficazes. Em A. hybridus, os tratamentos que apresentaram melhores níveis de controle foram o glyphosate e carfentrazone, aplicados isoladamente, e a mistura de glyphosate com flumioxazin, sulfentrazone, chlorimuron-ethyl e bentazon, sendo estes interações aditivas. No caso de G. parviflora, os tratamentos com flumioxazin e sulfentrazone apresentaram controle total, o mesmo acontecendo com as misturas de glyphosate com carfentrazone, flumioxazin, sulfentrazone, chlorimuron-ethyl ou bentazon.The intensive use of glyphosate as a non-selective herbicide for weed vegetation management has selected some tolerant weed species. Thus, it is important to study the synergistic or antagonic or additive effects of tank mixtures of glyphosate combined with alternative mechanism of action herbicides. An experiment was developed in a randomized complete design, using 12 treatments and four replications, under greenhouse conditions at University of São Paulo - USP/ESALQ - Piracicaba-SP, Brazil, with the weeds Richardia brasiliensis, Commelina benghalensis, Amaranthus hybridus, Galinsoga parviflora and Ipomoea grandifolia and applying glyphosate combined with the herbicides chlorimuron-ethyl, carfentrazone, bentazon, sulfentrazone and flumioxazin. The interactions were additive for the weeds I. grandifolia and C. benghalensis but the herbicides flumioxazin, sulfentrazone and carfentrazone sprayed alone and in mixture with glyphosate gave better control results. The interaction of glyphosate with sulfentrazone was antagonic in R. brasiliensis, whereas the glyphosate mixed with other herbicides was additive; however, the treatments using glyphosate and chlorimuron-ethyl or flumioxazin were more efficient in weed control. In A. hybridus, the best control results were glyphosate and carfentrazone alone and glyphosate mixed with flumioxazin, sulfentrazone, chlorimuron-ethyl and bentazon, all additives. In the case of G. parviflora, flumioxazin, sulfentrazone, chlorimuron and bentazon with glyphosate and flumioxazin and sulfentrazone gave excellent control.

  7. Glyphosate em mistura com herbicidas alternativos para o manejo de plantas daninhas / Glyphosate combined with alternative herbicides for vegetation management

    Scientific Electronic Library Online (English)

    P.A., Monquero; P.J., Christoffoleti; C.T.D., Santos.

    2001-12-01

    Full Text Available O uso intensivo de glyphosate como herbicida não-seletivo tem selecionado espécies de plantas daninhas tolerantes. Dessa forma, é importante que sejam estudadas misturas de tanque com herbicidas de mecanismos de ação alternativos e que apresentem efeitos sinergísticos ou aditivos. Por essa razão, fo [...] i instalado um experimento inteiramente casualizado, composto por 13 tratamentos e 4 repetições, em casa de vegetação da Universidade de São Paulo - ESALQ/USP, Piracicaba-SP, com as plantas daninhas Richardia brasiliensis, Commelina benghalensis, Amaranthus hybridus, Galinsoga parviflora e Ipomoea grandifolia em misturas de tanque dos herbicidas chlorimuron-ethyl, sulfentrazone, carfentrazone, bentazon ou flumioxazin com glyphosate. As interações foram aditivas para as plantas daninhas I. grandifolia e C. benghalensis, e os herbicidas flumioxazin, sulfentrazone e carfentrazone aplicados isoladamente e em mistura com glyphosate foram os que proporcionaram os melhores níveis de controle. A interação de glyphosate com sulfentrazone foi antagônica em R. brasiliensis; a mistura de glyphosate com os demais herbicidas estudados foi aditiva, sendo os tratamentos com mistura de glyphosate e chlorimuron-ethyl ou flumioxazin os mais eficazes. Em A. hybridus, os tratamentos que apresentaram melhores níveis de controle foram o glyphosate e carfentrazone, aplicados isoladamente, e a mistura de glyphosate com flumioxazin, sulfentrazone, chlorimuron-ethyl e bentazon, sendo estes interações aditivas. No caso de G. parviflora, os tratamentos com flumioxazin e sulfentrazone apresentaram controle total, o mesmo acontecendo com as misturas de glyphosate com carfentrazone, flumioxazin, sulfentrazone, chlorimuron-ethyl ou bentazon. Abstract in english The intensive use of glyphosate as a non-selective herbicide for weed vegetation management has selected some tolerant weed species. Thus, it is important to study the synergistic or antagonic or additive effects of tank mixtures of glyphosate combined with alternative mechanism of action herbicides [...] . An experiment was developed in a randomized complete design, using 12 treatments and four replications, under greenhouse conditions at University of São Paulo - USP/ESALQ - Piracicaba-SP, Brazil, with the weeds Richardia brasiliensis, Commelina benghalensis, Amaranthus hybridus, Galinsoga parviflora and Ipomoea grandifolia and applying glyphosate combined with the herbicides chlorimuron-ethyl, carfentrazone, bentazon, sulfentrazone and flumioxazin. The interactions were additive for the weeds I. grandifolia and C. benghalensis but the herbicides flumioxazin, sulfentrazone and carfentrazone sprayed alone and in mixture with glyphosate gave better control results. The interaction of glyphosate with sulfentrazone was antagonic in R. brasiliensis, whereas the glyphosate mixed with other herbicides was additive; however, the treatments using glyphosate and chlorimuron-ethyl or flumioxazin were more efficient in weed control. In A. hybridus, the best control results were glyphosate and carfentrazone alone and glyphosate mixed with flumioxazin, sulfentrazone, chlorimuron-ethyl and bentazon, all additives. In the case of G. parviflora, flumioxazin, sulfentrazone, chlorimuron and bentazon with glyphosate and flumioxazin and sulfentrazone gave excellent control.

  8. Level of UV-B radiation influences the effects of glyphosate-based herbicide on the spotted salamander.

    Science.gov (United States)

    Levis, Nicholas A; Johnson, Jarrett R

    2015-07-01

    Glyphosate-based herbicides are the number one pesticide in the United States and are used commonly around the world. Understanding the affects of glyphosate-based herbicides on non-target wildlife, for example amphibians, is critical for evaluation of regulations pertaining to the use of such herbicides. Additionally, it is important to understand how variation in biotic and abiotic environmental conditions, such as UV-B light regime, could potentially affect how glyphosate-based herbicides interact with non-target species. This study used artificial pond mesocosms to identify the effects of generic glyphosate-based herbicide (GLY-4 Plus) on mortality, cellular immune response, body size, and morphological plasticity of larvae of the spotted salamander (Ambystoma maculatum) under conditions that reflect moderate (UV(M)) and low (UV(L)) UV-B light regimes. Survival within a given UV-B level was unaffected by herbicide presence or absence. However, when herbicide was present, survival varied between UV-B levels with higher survival in UV(M) conditions. Herbicide presence in the UV(M) treatments also decreased body size and reduced cellular immune response. In the UV(L) treatments, the presence of herbicide increased body size and affected tail morphology. Finally, in the absence of herbicide, body size and cellular immune response were higher in UV(M) treatments compared to UV(L) treatments. Thus, the effects of herbicide on salamander fitness were dependent on UV-B level. As anthropogenic habitat modifications continue to alter landscapes that contain amphibian breeding ponds, salamanders may increasingly find themselves in locations with reduced canopy cover and increased levels of UV light. Our findings suggest that the probability of surviving exposure to the glyphosate-based herbicide used in this study may be elevated in more open canopy ponds, but the effects on other components of fitness may be varied and unexpected. PMID:25794558

  9. Architecturally sensitive retrofitting of PV to a residential block in Greece to reduce its carbon footprint

    Science.gov (United States)

    Panopoulou, Ismini

    Photovoltaic power is a unique energy source, with wide distribution potential, which can be integrated within the fabric of individual buildings, transforming the power generation in a less large-scale and regionally located issue. As a result, photovoltaic power is a free, clean and silent electrical supply that can be introduced into cities and residential areas. Over the past years, grid-connected, distributed photovoltaic power systems have become an explosively growing sector worldwide. This trend is expected to be continued in the future and solar systems may become a common building element of building construction. In Greece, where the main focus of the project is concentrated, the extended sunshine and the incentives of the new Renewable Energy Sources law of 2006, give a different perspective in photovoltaic investments. In the case study of Vera Water Residence complex in Athens, the viability of an architecturally sensitive retrofitting of PV was examined, from both financial and environmental aspects. The project was concentrated in one of the complex's buildings which was modelled in TAS simulator in order for the annual heating and cooling loads to be estimated. A closer to the reality estimation of electricity demand was made through the annual electricity bills of the building. The proposed building integrated photovoltaic system was designed in terms of following and respecting the aesthetics of the existing architecture of the complex while being as efficient as possible. The annual energy output and C02 emissions reductions were then calculated through RETScreen software analysis according to the location of the project and the characteristics of the PV system. Finally, an economic analysis has been included to the study, considering the installation cost, the annual savings and the embodied energy of the system, in order for the payback period of the investment to be determined. Finally, a small sensitivity analysis concerning the effect of different factors influencing the feasibility of the PV investment was carried out and as it was expected it had significant effect on the initially calculated the payback period value. The expected future increase of fuel prices and the reduction of the investment's initial cost due to government grants, added to the prospect of new future tax incentive and subsidies, have made the prospect of the project more attractive while significantly reducing the payback period.

  10. Noopept reduces the postischemic functional and metabolic disorders in the brain of rats with different sensitivity to hypoxia.

    Science.gov (United States)

    Zarubina, I V; Shabanov, P D

    2009-03-01

    Chronic cerebral ischemia was induced by ligation of both common carotid arteries in Wistar rats, divided by sensitivity to hypoxia into highly sensitive and low-sensitive. Noopept (peptide preparation), injected (0.5 mg/kg) during 7 days after occlusion of the carotid arteries, reduced the neurological disorders in rats with high and low sensitivity to hypoxia and improved their survival during the postischemic period. Noopept normalized behavior disordered by cerebral ischemia (according to the open field and elevated plus maze tests), prevented accumulation of LPO products and inhibition of antioxidant systems in the brain of rats with high and low sensitivity to hypoxia. Hence, noopept exhibited a neuroprotective effect in cerebral ischemia. PMID:19529857

  11. EPSPS amplification in glyphosate-resistant spiny amaranth (Amaranthus spinosus): a case of gene transfer via interspecific hybridization from glyphosate-resistant Palmer amaranth (Amaranthus palmeri

    Science.gov (United States)

    Amaranthus spinosus, a common weed of pastures, is a close relative of Amaranthus palmeri, a problematic agricultural weed with widespread glyphosate resistance. These two species have been known to hybridize, allowing for transfer of glyphosate resistance. Glyphosate-resistant A. spinosus was rec...

  12. Reduced baroreflex sensitivity in alcoholic cirrhosis: relations to hemodynamics and humoral systems.

    DEFF Research Database (Denmark)

    MØller, SØren; Iversen, Jens S

    2007-01-01

    In cirrhosis, arterial vasodilatation leads to central hypovolemia and activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. As the liver disease and circulatory dysfunction may affect baroreflex sensitivity (BRS), we assessed BRS in a large group of patients with cirrhosis and in controls who were all supine and some after 60 degrees passive head-up and 30 degrees head-down tilting in relation to central hemodynamics and activity of the sympathetic nervous and renin-angiotensin-aldosterone systems. One-hundred and five patients (Child classes A/B/C: 21/55/29) and 25 (n=11 + 14) controls underwent a full hemodynamic investigation. BRS was assessed by cross-spectral analysis of variabilities between blood pressure and heart rate time series. The median BRS was significantly lower in the supine cirrhotic patients, 3.7 (range 0.3-30.7) ms/mmHg than in matched controls (n=11): 14.3 (6.1-23.6) ms/mmHg, P<0.001. A stepwise multiple-regression analysis revealed that serum sodium (P=0.044),heart rate (P=0.027), and central circulation time (P=0.034) independently correlated with BRS. Head-down tilting had no effects on BRS, but, after head-up tilting, BRS was similar in the patients (n=23) and controls (n=14). In conclusion, BRS is reduced in cirrhosis in the supine position and relates to various aspects of cardiovascular dysfunction, but no further reduction was observed in parallel with the amelioration of the hyperdynamic circulation after head-up tilting. The results indicate that liver dysfunction and compensatory mechanisms to vasodilatation may be involved in the low BRS, which may contribute to poor cardiovascular adaptation in cirrhosis. Udgivelsesdato: 2007-Jun

  13. Reduced baroreflex sensitivity in alcoholic cirrhosis: relations to hemodynamics and humoral systems

    DEFF Research Database (Denmark)

    MØller, SØren; Iversen, Jens S

    2007-01-01

    In cirrhosis, arterial vasodilatation leads to central hypovolemia and activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. As the liver disease and circulatory dysfunction may affect baroreflex sensitivity (BRS), we assessed BRS in a large group of patients with cirrhosis and in controls who were all supine and some after 60 degrees passive head-up and 30 degrees head-down tilting in relation to central hemodynamics and activity of the sympathetic nervous and renin-angiotensin-aldosterone systems. One-hundred and five patients (Child classes A/B/C: 21/55/29) and 25 (n=11 + 14) controls underwent a full hemodynamic investigation. BRS was assessed by cross-spectral analysis of variabilities between blood pressure and heart rate time series. The median BRS was significantly lower in the supine cirrhotic patients, 3.7 (range 0.3-30.7) ms/mmHg than in matched controls (n=11): 14.3 (6.1-23.6) ms/mmHg, P<0.001. A stepwise multiple-regression analysis revealed that serum sodium (P=0.044),heart rate (P=0.027), and central circulation time (P=0.034) independently correlated with BRS. Head-down tilting had no effects on BRS, but, after head-up tilting, BRS was similar in the patients (n=23) and controls (n=14). In conclusion, BRS is reduced in cirrhosis in the supine position and relates to various aspects of cardiovascular dysfunction, but no further reduction was observed in parallel with the amelioration of the hyperdynamic circulation after head-up tilting. The results indicate that liver dysfunction and compensatory mechanisms to vasodilatation may be involved in the low BRS, which may contribute to poor cardiovascular adaptation in cirrhosis. Udgivelsesdato: 2007-Jun

  14. Appetitive Sensitization by Amphetamine does not Reduce its Ability to Produce Conditioned Taste Aversion to Saccharin

    OpenAIRE

    Scott-Railton, John; Arnold, Gretchen; Vezina, Paul

    2006-01-01

    Previous exposure to amphetamine attenuates its ability to induce conditioned taste aversion (CTA). Because amphetamine, unlike emetic agents like LiCl, possesses appetitive properties that sensitize when it is administered repeatedly, the present study assessed the contribution of sensitization to this US pre-exposure effect (US-PEE). It was found that not all sensitizing regimens of systemic amphetamine injections produce a US-PEE. In addition, previous exposure to amphetamine in the VTA, w...

  15. Glyphosate catabolism by Pseudomonas sp. strain PG2982.

    OpenAIRE

    Shinabarger, D L; Braymer, H. D.

    1986-01-01

    The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined by using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing [3-14C]glyphosate revealed that approximately 50 to 59% of the C-3 carbon was oxidized to CO2. Fractionation of stationary-phase cells labeled with [3-14C]glyphosate revealed that from 45 to 47% of the assimilated label is distributed to proteins and that the amino acids methionine and serin...

  16. Adsorption of glyphosate and aminomethylphosphonic acid in soils

    Science.gov (United States)

    Rampazzo, N.; Rampazzo Todorovic, G.; Mentler, A.; Blum, W. E. H.

    2013-03-01

    The results showed that glyphosate is initially adsorbed mostly in the upper 2 cm. It is than transported and adsorbed after few days in deeper soil horizons with concomitant increasing content of its metabolite aminomethylphosphonic acid. Moreover, Fe-oxides seem to be a key parameter for glyphosate and aminomethylphosphonic adsorption in soils. This study confirmed previous studies: the analysis showed lower contents of dithionite-soluble and Fe-oxides for the Chernozem, with consequently lower adsorption of glyphosate and aminomethylphosphonic as compared with the Cambisol and the Stagnosol.

  17. Resistência de Conyza canadensis e C. bonariensis ao herbicida glyphosate Glyphosate-resistance in Conyza canadensis and C. bonariensis

    Directory of Open Access Journals (Sweden)

    M.S. Moreira

    2007-03-01

    Full Text Available O objetivo deste trabalho foi avaliar, por meio de curvas de dose-resposta, a ocorrência de biótipos resistentes ao herbicida glyphosate em populações de Conyza canadensis e C. bonariensis, bem como propor tratamentos alternativos para esses biótipos. Os experimentos foram realizados em casa de vegetação, utilizando-se três populações de cada espécie: duas com suspeita de resistência ao herbicida glyphosate, coletadas em pomares de laranja localizados em duas regiões diferentes do Estado de São Paulo; e uma suscetível, coletada em área sem histórico de aplicação do herbicida. O delineamento experimental adotado foi o de blocos ao acaso, com quatro repetições. Para cada espécie, os tratamentos foram resultado da combinação fatorial entre as três populações e os tratamentos herbicidas (oito doses de glyphosate ou cinco tratamentos alternativos. As doses de glyphosate foram (g e.a. ha¹: 90, 180, 360, 720, 1.440, 2.880, 5.760 e testemunha sem aplicação. Como alternativas de controle, foram testados os seguintes tratamentos (g ha-1: glyphosate + 2,4-D (1.440 + 1.005, glyphosate + metsulfuron (1.440 + 2,4, glyphosate + metsulfuron (1.440 + 3,6, glyphosate + metribuzin (1.440 + 480 e testemunha sem aplicação. A partir dos resultados, comprovou-se a existência de populações de ambas as espécies com biótipos resistentes ao herbicida glyphosate, com diferentes níveis de resistência. Todos os tratamentos herbicidas alternativos controlaram de forma eficiente as três populações de cada espécie.The objective of this research was to evaluate, through dose-response curves, the occurrence of glyphosate-resistant biotypes in populations of Conyza canadensis and C. bonariensis; as well as to propose alternative treatments to these biotypes. The experiments were conducted in a greenhouse, using three populations of each species: two with suspicion of resistance to the herbicide glyphosate, and collected in orange orchards located in two different São Paulo state regions; and a susceptible one, collected in an area without herbicide application history. The experimental design adopted was randomized blocks, with four replicates. For each species, the treatments were the result of a factorial combination among the three populations and the herbicide treatments (eight rates of glyphosate or five alternative treatments. The glyphosate rates used were (g e.a. ha-1: 90, 180, 360, 720, 1.440, 2.880, 5.760 and checks without application. As control alternative, the following treatments (g ha-1 were tested: glyphosate + 2,4-D (1.440 + 1.005, glyphosate + metsulfuron (1.440 + 2,4, glyphosate + metsulfuron (1.440 + 3,6, glyphosate + metribuzin (1440 + 480 and checks without application. The results obtained proved the existence of populations of both species with glyphosate-resistant biotypes, with different levels of resistance. All the alternative herbicide treatments controlled efficiently the three populations of each species.

  18. Resistência de Conyza canadensis e C. bonariensis ao herbicida glyphosate / Glyphosate-resistance in Conyza canadensis and C. bonariensis

    Scientific Electronic Library Online (English)

    M.S., Moreira; M., Nicolai; S.J.P., Carvalho; P.J., Christoffoleti.

    2007-03-01

    Full Text Available O objetivo deste trabalho foi avaliar, por meio de curvas de dose-resposta, a ocorrência de biótipos resistentes ao herbicida glyphosate em populações de Conyza canadensis e C. bonariensis, bem como propor tratamentos alternativos para esses biótipos. Os experimentos foram realizados em casa de vege [...] tação, utilizando-se três populações de cada espécie: duas com suspeita de resistência ao herbicida glyphosate, coletadas em pomares de laranja localizados em duas regiões diferentes do Estado de São Paulo; e uma suscetível, coletada em área sem histórico de aplicação do herbicida. O delineamento experimental adotado foi o de blocos ao acaso, com quatro repetições. Para cada espécie, os tratamentos foram resultado da combinação fatorial entre as três populações e os tratamentos herbicidas (oito doses de glyphosate ou cinco tratamentos alternativos). As doses de glyphosate foram (g e.a. ha¹): 90, 180, 360, 720, 1.440, 2.880, 5.760 e testemunha sem aplicação. Como alternativas de controle, foram testados os seguintes tratamentos (g ha-1): glyphosate + 2,4-D (1.440 + 1.005), glyphosate + metsulfuron (1.440 + 2,4), glyphosate + metsulfuron (1.440 + 3,6), glyphosate + metribuzin (1.440 + 480) e testemunha sem aplicação. A partir dos resultados, comprovou-se a existência de populações de ambas as espécies com biótipos resistentes ao herbicida glyphosate, com diferentes níveis de resistência. Todos os tratamentos herbicidas alternativos controlaram de forma eficiente as três populações de cada espécie. Abstract in english The objective of this research was to evaluate, through dose-response curves, the occurrence of glyphosate-resistant biotypes in populations of Conyza canadensis and C. bonariensis; as well as to propose alternative treatments to these biotypes. The experiments were conducted in a greenhouse, using [...] three populations of each species: two with suspicion of resistance to the herbicide glyphosate, and collected in orange orchards located in two different São Paulo state regions; and a susceptible one, collected in an area without herbicide application history. The experimental design adopted was randomized blocks, with four replicates. For each species, the treatments were the result of a factorial combination among the three populations and the herbicide treatments (eight rates of glyphosate or five alternative treatments). The glyphosate rates used were (g e.a. ha-1): 90, 180, 360, 720, 1.440, 2.880, 5.760 and checks without application. As control alternative, the following treatments (g ha-1) were tested: glyphosate + 2,4-D (1.440 + 1.005), glyphosate + metsulfuron (1.440 + 2,4), glyphosate + metsulfuron (1.440 + 3,6), glyphosate + metribuzin (1440 + 480) and checks without application. The results obtained proved the existence of populations of both species with glyphosate-resistant biotypes, with different levels of resistance. All the alternative herbicide treatments controlled efficiently the three populations of each species.

  19. Distribuição de glyphosate e acúmulo de nutrientes em biótipos de azevém Glyphosate distribution and nutrient accumulation in ryegrass biotypes

    OpenAIRE

    E.A. Ferreira; Silva, A. A.; M.R Reis; Santos, J. B.; de Oliveira, J. A.; L. VARGAS; K.R. Khouri; A.A. Guimarães

    2008-01-01

    Objetivou-se neste trabalho avaliar o acúmulo de nutrientes e a translocação de glyphosate em biótipos de azevém. Para isso, foram montados dois ensaios: no primeiro aplicou-se 14C-glyphosate, adicionando 10 µL da calda sobre a face adaxial da primeira folha com lígula totalmente visível, quando as plantas de azevém apresentavam três perfilhos. A quantidade de glyphosate absorvido, translocado e exsudado foi avaliada 64 horas após aplicação, por meio da medição da radiação emitida pelo 14C-gl...

  20. Researches regarding extractable glyphosate residues from different soils.

    Science.gov (United States)

    Alexa, Ersilia; Lazureanu, Aurel; Alda, Simion; Negrea, Monica; Iordanescu, Olimpia

    2008-01-01

    GLyphosate (N-phosphonomethyl-glycine) is a systemic, broad spectrum herbicide effective against most plant species, including annual and perennial species and is one of the world's most widely used herbicide. To glyphosate applied treatments, a part of active agent comes in contact with soil surface, adsorbing to soil compounds, while another part remains in soil solution. The adsorbing to soil compounds represents a feat importance conditioning the herbicide presence in soil solution and so, his availability to degradation and dispersion in the environment. In this paper work, the extractable glyphosate residues from soil solution have been determined through HPLC-FLD. Substrates used were Black Chernozem, Typical Gleysoil, Slight Vertisol, with moderate carbonatation. The experimental results indicated that the extractable glyphosate residue fractions from soil diminish (<20%), depending of soil parameters and decrease in this order: Gleysoil, Black Chernozem, Slight Vertisol. PMID:19226836

  1. Acute toxicity and sublethal effects of the mixture glyphosate (Roundup® Active and Cosmo-Flux®411F to anuran embryos and tadpoles of four Colombian species

    Directory of Open Access Journals (Sweden)

    Liliana Marcela Henao Muñoz

    2015-03-01

    Full Text Available Glyphosate is the most widely used herbicide in the world with application in agriculture, forestry, industrial weed control, garden and aquatic environments. However, its use is highly controversial for the possible impact on not-target organisms, such as amphibians, which are vanishing at an alarming and rapid rate. Due to the high solubility in water and ionic nature, the glyphosate requires of surfactants to increase activity. In addition, for the control of coca (Erythroxylum coca and agricultural weeds in Colombia, formulated glyphosate is mixed and sprayed with the adjuvant Cosmo-Flux®411F to increase the penetration and activity of the herbicide. This study evaluates the acute toxic and sublethal effects (embryonic development, tadpole body size, tadpole swimming performance of the mixture of the formulated glyphosate Roundup® Active and Cosmo-Flux®411F to anuran embryos and tadpoles of four Colombian species under 96h laboratory standard tests and microcosms, which are more similar to field conditions as they include soil, sand and macrophytes. In the laboratory, embryos and tadpoles of Engystomops pustulosus were the most tolerant (LC50=3 904µg a.e./L; LC50=2 799µg a.e./L, respectively, while embryos and tadpoles of Hypsiboas crepitans (LC50=2 203µg a.e./L; LC50=1 424µg a.e./L, respectively were the most sensitive. R. humboldti and R. marina presented an intermediate toxicity. Embryos were significantly more tolerant to the mixture than tadpoles, which could be likely attributed to the exclusion of chemicals by the embryonic membranes and the lack of organs, such as gills, which are sensitive to surfactants. Sublethal effects were observed for the tadpole body size, but not for the embryonic development and tadpole swimming performance. In microcosms, no toxicity (LC50 could not be estimated, or sublethal responses were observed at concentrations up to fourfold (14.76kg glyphosate a.e./ha the highest field application rate of 3.69kg glyphosate a.e./ha. Thus, toxicity was less in the microcosms than in laboratory tests, which may be attributed to the presence of sediments and organic matter which rapidly adsorb glyphosate and surfactants such as POEA. It is concluded that the mixture of glyphosate (Roundup® Active and Cosmo-Flux®411F, as used in the field, has a negligible toxic effect to embryos and tadpoles of the species tested in this study.

  2. Acute toxicity and sublethal effects of the mixture glyphosate (Roundup Active) and Cosmo-Flux 411F to anuran embryos and tadpoles of four Colombian species.

    Science.gov (United States)

    Henao Muñoz, Liliana Marcela; Montes Rojas, Claudia Marsela; Bernal Bautista, Manuel Hernando

    2015-03-01

    Glyphosate is the most widely used herbicide in the world with application in agriculture, forestry, industrial weed control, garden and aquatic environments. However, its use is highly controversial for the possible impact on not-target organisms, such as amphibians, which are vanishing at an alarming and rapid rate. Due to the high solubility in water and ionic nature, the glyphosate requires of surfactants to increase activity. In addition, for the control of coca (Erythroxylum coca) and agricultural weeds in Colombia, formulated glyphosate is mixed and sprayed with the adjuvant Cosmo-Flux 411F to increase the penetration and activity of the herbicide. This study evaluates the acute toxic and sublethal effects (embryonic development, tadpole body size, tadpole swimming performance) of the mixture of the formulated glyphosate Roundup Active and Cosmo-Flux 411F to anuran embryos and tadpoles of four Colombian species under 96h laboratory standard tests and microcosms, which are more similar to field conditions as they include soil, sand and macrophytes. In the laboratory, embryos and tadpoles of Engystomops pustulosus were the most tolerant (LC50 = 3904 microg a.e./L; LC50=2 799 pg a.e./L, respectively), while embryos and tadpoles of Hypsiboas crepitans (LC50=2 203 microg a.e./L; LC50=1424 microgg a.e./L, respectively) were the most sensitive. R. humboldti and R. marina presented an intermediate toxicity. Embryos were significantly more tolerant to the mixture than tadpoles, which could be likely attributed to the exclusion of chemicals by the embryonic membranes and the lack of organs, such as gills, which are sensitive to surfactants. Sublethal effects were observed for the tadpole body size, but not for the embryonic development and tadpole swimming performance. In microcosms, no toxicity (LC50 could not be estimated), or sublethal responses were observed at concentrations up to fourfold (14.76 kg glyphosate a.e./ha) the highest field application rate of 3.69 kg glyphosate a.e./ha. Thus, toxicity was less in the microcosms than in laboratory tests, which may be attributed to the presence of sediments and organic matter which rapidly adsorb glyphosate and surfactants such as POEA. It is concluded that the mixture of glyphosate (Roundup Active) and Cosmo-Flux*411F, as used in the field, has a negligible toxic effect to embryos and tadpoles of the species tested in this study. PMID:26299127

  3. Transgenic tobacco simultaneously overexpressing glyphosate N-acetyltransferase and 5-enolpyruvylshikimate-3-phosphate synthase are more resistant to glyphosate than those containing one gene.

    Science.gov (United States)

    Liu, Yunjun; Cao, Gaoyi; Chen, Rongrong; Zhang, Shengxue; Ren, Yuan; Lu, Wei; Wang, Jianhua; Wang, Guoying

    2015-08-01

    5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS) and glyphosate N-acetyltransferase (GAT) can detoxify glyphosate by alleviating the suppression of shikimate pathway. In this study, we obtained transgenic tobacco plants overexpressing AM79 aroA, GAT, and both of them, respectively, to evaluate whether overexpression of both genes could confer transgenic plants with higher glyphosate resistance. The transgenic plants harboring GAT or AM79 aroA, respectively, showed good glyphosate resistance. As expected, the hybrid plants containing both GAT and AM79 aroA exhibited improved glyphosate resistance than the transgenic plants overexpressing only a single gene. When grown on media with high concentration of glyphosate, seedlings containing a single gene were severely inhibited, whereas plants expressing both genes were affected less. When transgenic plants grown in the greenhouse were sprayed with glyphosate, less damage was observed for the plants containing both genes. Metabolomics analysis showed that transgenic plants containing two genes could maintain the metabolism balance better than those containing one gene after glyphosate treatment. Glyphosate treatment did not lead to a huge increase of shikimate contents of tobacco leaves in transgenic plants overexpressing two genes, whereas significant increase of shikimate contents in transgenic plants containing only a single gene was observed. These results demonstrated that pyramiding both aroA and GAT in transgenic plants can enhance glyphosate resistance, and this strategy can be used for the development of transgenic glyphosate-resistant crops. PMID:25822532

  4. Reduced sensitivity to emotional prosody in congenital amusia rekindles the musical protolanguage hypothesis

    DEFF Research Database (Denmark)

    Thompson, William Forde; Marin, Manuela M; Stewart, Lauren

    2012-01-01

    A number of evolutionary theories assume that music and language have a common origin as an emotional protolanguage that remains evident in overlapping functions and shared neural circuitry. The most basic prediction of this hypothesis is that sensitivity to emotion in speech prosody derives from the capacity to process music. We examined sensitivity to emotion in speech prosody in a sample of individuals with congenital amusia, a neurodevelopmental disorder characterized by deficits in processi...

  5. Reduced sensitivity to emotional prosody in congenital amusia rekindles the musical protolanguage hypothesis

    OpenAIRE

    Thompson, William Forde; Marin, Manuela M.; Stewart, Lauren

    2012-01-01

    A number of evolutionary theories assume that music and language have a common origin as an emotional protolanguage that remains evident in overlapping functions and shared neural circuitry. The most basic prediction of this hypothesis is that sensitivity to emotion in speech prosody derives from the capacity to process music. We examined sensitivity to emotion in speech prosody in a sample of individuals with congenital amusia, a neurodevelopmental disorder characterized by deficits in proce...

  6. Resistência de azevém (Lolium multiflorum) ao herbicida glyphosate Resistance of italian ryegrass (Lolium multiflorum) to glyphosate

    OpenAIRE

    E.S. Roman; L. VARGAS; M.A Rizzardi; R.W. Mattei

    2004-01-01

    O azevém é uma gramínea de ciclo anual, constituindo-se com freqüência em planta infestante em lavouras de trigo do Rio Grande do Sul. Em experimentos realizados em casa de vegetação e no campo, foi avaliada a suscetibilidade de dois biótipos de azevém ao herbicida glyphosate, bem como a eficiência de herbicidas de ação total na dessecação de Lolium multiflorum para a semeadura direta de trigo. O delineamento experimental foi completamente casualizado em casa de vegetação e de blocos ao acaso...

  7. A glyphosate-based pesticide impinges on transcription

    International Nuclear Information System (INIS)

    Widely spread chemicals used for human benefits may exert adverse effects on health or the environment, the identification of which are a major challenge. The early development of the sea urchin constitutes an appropriate model for the identification of undesirable cellular and molecular targets of pollutants. The widespread glyphosate-based pesticide affected sea urchin development by impeding the hatching process at millimolar range concentration of glyphosate. Glyphosate, the active herbicide ingredient of Roundup, by itself delayed hatching as judged from the comparable effect of different commercial glyphosate-based pesticides and from the effect of pure glyphosate addition to a threshold concentration of Roundup. The surfactant polyoxyethylene amine (POEA), the major component of commercial Roundup, was found to be highly toxic to the embryos when tested alone and therefore could contribute to the inhibition of hatching. Hatching, a landmark of early development, is a transcription-dependent process. Correlatively, the herbicide inhibited the global transcription, which follows fertilization at the 16-cell stage. Transcription inhibition was dose-dependent in the millimolar glyphosate range concentration. A 1257-bp fragment of the hatching enzyme transcript from Sphaerechinus granularis was cloned and sequenced; its transcription was delayed by 2 h in the pesticide-treated embryos. Because transcription is a fundamental basic biological process, the pesticide may be of health concern by inhalation near herbicide spraying at a concentration 25 times the adverse transcription concentration in the sprayed microdroplets

  8. PHYTO-MICROBIAL DEGRADATION OF GLYPHOSATE IN RIYADH AREA

    Directory of Open Access Journals (Sweden)

    ABDEL-MEGEED A.

    2013-09-01

    Full Text Available Greenhouse studies were conducted to determine the ability of plant Amaranth, Amaranthus caudate and two isolated bacterial strains from rhizosphere region for cleaning up glyphosate residues in soil and plants. The analytical study of the biodegradation of glyphosate was carried out in the laboratory conditions. Amaranth, Amaranthus caudate and two isolated bacterial strains namely Pseudomonas aeruginosa and Bacillus megaterium could degrade glyphosate in 5 days. These results suggested that phytoremediation could accelerate the degradation of glyphosate residues in plants and in rhizosphere region as well. Glyphosate had strong effect on bacterial DNA where many DNA bands were affected. This could be explained that the effect of herbicide glyphosate on the protein profile may reflex somehow DNA mutation occurred during the assimilation of those toxic compounds. Therefore, the alteration occurred in both DNA and protein profiles is considered a degree of tolerance that lead to DNA mutation to cope with the assimilation of this compound. Therefore, the phytoremediation way could be a promising tool in program is to protect public health and the environment by ensuring the safety and availability of herbicides and pesticide alternatives.

  9. Intoxicação de espécies de eucalipto submetidas à deriva do glyphosate Intoxication of eucalypt species under glyphosate drift

    Directory of Open Access Journals (Sweden)

    L.D. Tuffi Santos

    2006-06-01

    Full Text Available O glyphosate é o herbicida mais utilizado em áreas de reflorestamento de eucalipto. Nessas áreas tem sido freqüente a verificação de sintomas de intoxicação devido à deriva. Entretanto, trabalhos de pesquisa e observações de campo indicam comportamento diferencial entre as espécies e os clones de eucalipto quando em contato com o glyphosate. O presente trabalho teve como objetivo avaliar os efeitos da deriva simulada de glyphosate, por meio de doses reduzidas, no crescimento de cinco espécies de eucalipto. Utilizou-se o esquema fatorial 5x5, sendo cinco espécies (Eucalyptus urophylla, E. grandis, E. pellita, E. resinifera e E. saligna e cinco doses (0; 43,2; 86,4; 172,8; e 345,6 g ha-1 de glyphosate, no delineamento em blocos casualizados com quatro repetições. A aplicação do herbicida foi feita sobre as plantas, de modo que não atingisse o terço superior, 23 dias após o plantio destas. Os sintomas de intoxicação causados pelo glyphosate foram semelhantes nas diferentes espécies, sendo caracterizados por murcha, clorose e enrolamento foliar, e, no caso de maiores doses, por necroses e senescência foliar. Plantas submetidas a doses acima de 86,4 g ha-1 de glyphosate foram severamente intoxicadas, afetando o seu crescimento, resultando em menor altura, diâmetro do caule e massa seca aos 45 dias após aplicação do herbicida. Entre as espécies estudadas, E. resinifera foi mais tolerante à deriva de glyphosate, apresentando menores valores de intoxicação e maior incremento em altura e diâmetro, mesmo nas plantas submetidas às maiores doses, o que não foi observado nas demais espécies.Glyphosate is the most used herbicide in eucalypt plantations. In these areas intoxication symptoms are often observed due to glyphosate drift. However, research works and field observations indicate different behaviors among eucalypt species and clones with glyphosate contact. This work aimed to evaluate the effects of simulated glyphosate drift, by means of herbicide subdoses, on the growth of five eucalypt species. The factorial model used five species (Eucalyptus urophylla, E. grandis, E. pellita, E. resinifera and E. saligna and five subdoses (0, 43.2, 86.4, 172.8, and 345.6 g ha-1 glyphosate arranged in a randomized block design, with four repetitions. Glyphosate applications were performed on the plants in such a way as to avoid reaching the upper third part of the plants 23 days after seed planting. The intoxication symptoms caused by glyphosate were similar for the different species, as characterized by wilt, chlorosis and leaf curling and in the case of larger doses, by necrosis and leaf senescence. Plants treated with subdoses above 86.4 g ha-1 glyphosate were severely intoxicated and were affected in their growth, with smaller height, diameter and less dry matter after 45 days of herbicide application. Among the species studied, E. resinifera showed to be the most tolerant to glyphosate drift, displaying the lowest intoxication values and greatest height and diameter increases, a fact not observed in the other species.

  10. Reduced dihydroxyacetone sensitivity and normal sensitivity to glyceraldehyde and oxidizing agent of ATP-sensitive K+ channels of pancreatic beta cells in NIDDM rats.

    OpenAIRE

    Song, D.K.; Park, W K; Bae, J.H.; Park, M K; Kim, S.J.; Ho, W.K.; Earm, Y. E.

    1997-01-01

    The inhibition of ATP-sensitive K+(KATP) channels in pancreatic beta cells is a key step of insulin secretion induced by glucose. Glucose-induced insulin secretion from the beta cells is selectively impaired in patients with noninsulin-dependent diabetes mellitus (NIDDM) and in animal models of it. In order to clarify the site of this abnormal glucose response, we studied the effects of insulin secretagogues and sulfhydryl oxidizing agent, 2,2'-dithio-bis (5-nitropyridine) (DTBNP), on KATP ch...

  11. Aplicação foliar de manganês em soja transgênica tolerante ao glyphosate Foliar application of manganese in transgenic soybean tolerant to glyphosate

    OpenAIRE

    Claudir José Basso; Antônio Luis Santi; Fabiane Pinto Lamego; Eduardo Girotto

    2011-01-01

    O amarelecimento da soja Roundup Ready após aplicação do glyphosate pode estar associado à deficiência momentânea de manganês. Por isso, com a hipótese de que soja tolerante ao glyphosate necessitaria de uma adição suplementar de manganês, o objetivo deste trabalho foi avaliar diferentes manejos na aplicação foliar de manganês sobre alguns parâmetros da soja. Foram desenvolvidos dois experimentos, um no município de Taquaruçú do Sul e outro em Boa Vista das Missões, RS, no ano agrícola 2009/2...

  12. Resistência de Conyza canadensis e C. bonariensis ao herbicida glyphosate Glyphosate-resistance in Conyza canadensis and C. bonariensis

    OpenAIRE

    Moreira, M. S.; Nicolai, M.; S.J.P. Carvalho; P.J. Christoffoleti

    2007-01-01

    O objetivo deste trabalho foi avaliar, por meio de curvas de dose-resposta, a ocorrência de biótipos resistentes ao herbicida glyphosate em populações de Conyza canadensis e C. bonariensis, bem como propor tratamentos alternativos para esses biótipos. Os experimentos foram realizados em casa de vegetação, utilizando-se três populações de cada espécie: duas com suspeita de resistência ao herbicida glyphosate, coletadas em pomares de laranja localizados em duas regiões diferentes do Estado de S...

  13. Pisolithus sp. tolerance to glyphosate and isoxaflutole in vitro / Tolerância de pisolithus sp. a glyphosate e isoxaflutole in vitro

    Scientific Electronic Library Online (English)

    Mayara Cristina Silva, Fernandes; Lidiomar Soares da, Costa; Paulo Henrique, Grazziotti; Danielle Cristina Fonseca Santos, Grazziotti; José Barbosa dos, Santos; Márcio José, Rossi.

    2014-06-01

    Full Text Available Os fungos ectomicorrízicos possuem tolerância diferenciada aos herbicidas e podem promover a sobrevivência e crescimento das plantas de eucalipto. O objetivo deste trabalho foi avaliar a tolerância de isolados do fungo ectomicorrízico . Pisolithus sp. aos herbicidas glyphosate e isoxaflutole. Os iso [...] lados avaliados foram D3, D16, D17, Pt24 e UFVJM04 e as concentrações de glyphosate no meio líquido, de 0, 32, 63, 127 e 254 mg L-1, enquanto no meio sólido, de 0, 32, 63, 127, 254, 507 e 1.014 mg L-1. Para o isoxaflutole nos dois meios de cultura, as concentrações foram de: 0, 295, 589, 1.178 e 2.355 mg L-1. Os ensaios foram independentes para cada herbicida e tipo de meio de cultura. A tolerância dos isolados foi dependente do herbicida e da sua concentração em cada meio. O Pt24 foi o mais tolerante ao glyphosate e o UFVJM04, ao isoxaflutole. O glyphosate foi mais tóxico aos isolados de Pisolithus sp. do que o isoxaflutole. Abstract in english The ectomycorrhizal fungi have different tolerance to herbicides and may promote the survival and growth of the eucalypts tree. This study aimed to evaluate the tolerance of Pisolithus sp. isolates to glyphosate and isoxaflutole. The isolates evaluated were D3, D16, D17, Pt24 and UFVJM04. Glyphosate [...] concentrations were: 0, 32, 63, 127 and 254 mg L-1 in liquid medium; 0, 32, 63, 127, 254, 507 and 1014 mg L-1 in solid medium. For isoxaflutole, the concentrations were 0, 295, 589, 1178 and 2355 mg L-1 for both media. Assays were independent for each herbicide and culture medium. The tolerance of isolates depended on the herbicide and its concentration in each type of culture medium. Pt24 was the most tolerant to glyphosate and the UFVJM04 to isoxaflutole. Glyphosate was more toxic to isolates of Pisolithus than isoxaflutole.

  14. Selectivity of glyphosate tank mixtures for RR soybean Seletividade de glyphosate em misturas em tanque para soja RR

    OpenAIRE

    D.G. Alonso; J. Constantin; R.S. Oliveira JR; J.G.Z. Arantes; S.D. Cavalieri; Santos, G.; F.A. Rios; L.H.M Franchini

    2011-01-01

    An active ingredients mixture of different action mechanisms is an essential tool to prevent or manage areas with resistant weeds. However, it is important that such a mixture provides adequate selectivity to the crop. The aim of this work was to evaluate glyphosate selectivity to glyphosate-resistant (RR) soybean, and also verify if there is selectivity in mixtures with other active ingredients applied postemergence aimed at new control strategies, which might be used in RR soybean cultivati...

  15. The effect of glyphosate on the frequency of micronuclei in bovine lymphocytes in vitro

    OpenAIRE

    Piešova Elena

    2005-01-01

    Glyphosate is a widely used broad-spectrum herbicide that has expanded its applications on plant varieties that are genetically modified to tolerate glyphosate treatment. The aim of this study was to determine the frequency of micronuclei (MNi) in bovine peripheral lymphocytes after exposure to glyphosate in vitro. The cytokinesis block micronucleus assay (CBMN) for estimation of genotoxic activity was used. The obtained results indicate that glyphosate weakly induced micronuclei in bovine pe...

  16. Adsorção de glifosato sobre solos e minerais Adsorption of glyphosate on soils and minerals

    OpenAIRE

    Luís R. M. Toni; Henrique de Santana; Dimas A. M. Zaia

    2006-01-01

    Glyphosate, an enzyme inhibitor herbicide, has been widely used around the world in agriculture. Dr. John Franz from Monsanto Corporation (USA) discovered glyphosate in 1970. It has been showed that glyphosate is strongly adsorbed by inorganic soil components especially aluminium and iron oxides, and the phosphate group is involved in this interaction. The inactivation of glyphosate in soils can last for days or even months depending on soil characteristics. The addition of phosphate from fer...

  17. Differential Effects of Glyphosate and Roundup on Human Placental Cells and Aromatase

    OpenAIRE

    Richard, Sophie; Moslemi, Safa; Sipahutar, Herbert; Benachour, Nora; Seralini, Gilles-Eric

    2005-01-01

    Roundup is a glyphosate-based herbicide used worldwide, including on most genetically modified plants that have been designed to tolerate it. Its residues may thus enter the food chain, and glyphosate is found as a contaminant in rivers. Some agricultural workers using glyphosate have pregnancy problems, but its mechanism of action in mammals is questioned. Here we show that glyphosate is toxic to human placental JEG3 cells within 18 hr with concentrations lower than those found with agricult...

  18. Degradation of the Phosphonate Herbicide Glyphosate by Arthrobacter atrocyaneus ATCC 13752

    OpenAIRE

    Pipke, Rüdiger; Amrhein, Nikolaus

    1988-01-01

    Of nine authentic Arthrobacter strains tested, only A. atrocyaneus ATCC 13752 was capable of using the herbicide glyphosate [N-(phosphonomethyl)glycine] as its sole source of phosphorus. Contrary to the previously isolated Arthrobacter sp. strain GLP-1, which degrades glyphosate via sarcosine, A. atrocyaneus metabolized glyphosate to aminomethylphosphonic acid. The carbon of aminomethylphosphonic acid was entirely converted to CO2. This is the first report on glyphosate degradation by a bacte...

  19. Glyphosate detection with ammonium nitrate and humic acids as potential interfering substances by pulsed voltammetry technique

    OpenAIRE

    MARTÍNEZ GIL, PABLO; Laguarda Miró, Nicolás; Soto Camino, Juan; Masot Peris, Rafael

    2013-01-01

    Pulsed voltammetry has been used to detect and quantify glyphosate on buffered water in presence of ammonium nitrate and humic substances. Glyphosate is the most widely used herbicide active ingredient in the world. It is a non-selective broad spectrum herbicide but some of its health and environmental effects are still being discussed. Nowadays, glyphosate pollution in water is being monitored but quantification techniques are slow and expensive. Glyphosate wastes are often detected in count...

  20. Leaching of Glyphosate and Aminomethylphosphonic Acid from an Agricultural Field over a Twelve-Year Period

    DEFF Research Database (Denmark)

    Norgaard, Trine; Moldrup, Per; Ferré, Ty P A; Olsen, Preben; Rosenbom, Annette E.; de Jonge, Lis Wollesen

    2014-01-01

    The globally-used herbicide glyphosate (N-(phosphonomethyl)glycine) and its most frequently detected metabolite, aminomethylphosphonic acid (AMPA), were studied in a unique 12-year field-scale monitoring program. The leaching of glyphosate, AMPA, and soil particles were studied in a shallow drainage system beneath a 1.26 ha field. Five annual glyphosate applications were applied with different autumn application dates. Solute mass flux from the drain system following the five glyphosate applicat...

  1. Temporal Patterns of Glyphosate Leaching at a Loamy Agricultural Field in Denmark

    DEFF Research Database (Denmark)

    Nørgaard, Trine; Møldrup, Per; Olsen, Preben; Rosenbom, Annette Elisabeth; de Jonge, Lis Wollesen

    2013-01-01

    Glyphosate is a herbicide used worldwide for weed control in agriculture. Glyphosate is believed to pose a low risk for groundwater reservoirs due to its strong sorption to soil minerals and fast degradation. However, during the last ten years several studies have shown detections of glyphosate in drainage water and groundwater at concentrations exceeding the EU drinking water quality criterion of 0.1 µg L-1. This study presents a unique 12-year time series of monitoring results for glyphosate (...

  2. Comparative environmental impacts of glyphosate and conventional herbicides when used with glyphosate-tolerant and non-tolerant crops

    International Nuclear Information System (INIS)

    The introduction of glyphosate-tolerant (GT) crops is expected to mitigate the environmental contamination by herbicides because glyphosate is less persistent and toxic than the herbicides used on non-GT crops. Here, we compared the environmental balances of herbicide applications for both crop types in three French field trials. The dynamic of herbicides and their metabolites in soil, groundwater and air was simulated with PRZM model and compared to field measurements. The associated impacts were aggregated with toxicity potentials calculated with the fate and exposure model USES for several environmental endpoints. The impacts of GT systems were lower than those of non-GT systems, but the accumulation in soils of one glyphosate metabolite (aminomethylphosphonic acid) questions the sustainability of GT systems. The magnitude of the impacts depends on the rates and frequency of glyphosate application being highest for GT maize monoculture and lowest for combination of GT oilseed rape and non-GT sugarbeet crops. - The impacts of herbicide applications on glyphosate-tolerant crops could be higher than expected due to the accumulation of a metabolite of glyphosate in soils.

  3. Comparative environmental impacts of glyphosate and conventional herbicides when used with glyphosate-tolerant and non-tolerant crops

    Energy Technology Data Exchange (ETDEWEB)

    Mamy, Laure, E-mail: laure.mamy@versailles.inra.f [INRA-AgroParisTech, UMR 1091 Environnement et Grandes Cultures, 78850 Thiverval-Grignon (France); Gabrielle, Benoit, E-mail: benoit.gabrielle@agroparistech.f [INRA-AgroParisTech, UMR 1091 Environnement et Grandes Cultures, 78850 Thiverval-Grignon (France); Barriuso, Enrique, E-mail: barriuso@grignon.inra.f [INRA-AgroParisTech, UMR 1091 Environnement et Grandes Cultures, 78850 Thiverval-Grignon (France)

    2010-10-15

    The introduction of glyphosate-tolerant (GT) crops is expected to mitigate the environmental contamination by herbicides because glyphosate is less persistent and toxic than the herbicides used on non-GT crops. Here, we compared the environmental balances of herbicide applications for both crop types in three French field trials. The dynamic of herbicides and their metabolites in soil, groundwater and air was simulated with PRZM model and compared to field measurements. The associated impacts were aggregated with toxicity potentials calculated with the fate and exposure model USES for several environmental endpoints. The impacts of GT systems were lower than those of non-GT systems, but the accumulation in soils of one glyphosate metabolite (aminomethylphosphonic acid) questions the sustainability of GT systems. The magnitude of the impacts depends on the rates and frequency of glyphosate application being highest for GT maize monoculture and lowest for combination of GT oilseed rape and non-GT sugarbeet crops. - The impacts of herbicide applications on glyphosate-tolerant crops could be higher than expected due to the accumulation of a metabolite of glyphosate in soils.

  4. Práticas de manejo e a resistência de Euphorbia heterophylla aos inibidores da ALS e tolerância ao glyphosate no Rio Grande do Sul Management practices x Euphorbia heterophylla resistance to ALS-inhibitors and tolerance to glyphosate in Rio Grande do Sul

    Directory of Open Access Journals (Sweden)

    L. Vargas

    2013-06-01

    Full Text Available A utilização intensiva do glyphosate nas lavouras de soja Roundup Ready® (RR no Rio Grande do Sul (RS, nos últimos anos, pode ter selecionado biótipos de leiteira (Euphorbia heterophylla resistentes ao herbicida. Esse cenário dificultará ainda mais o manejo da espécie, já que permanecem indícios da presença de biótipos resistentes também em herbicidas inibidores da acetolactato sintase (ALS. Assim, os objetivos deste trabalho foram avaliar a sensibilidade da leiteira a herbicidas inibidores da ALS e ao glyphosate, verificar a distribuição dos biótipos resistentes no RS e determinar os principais fatores agronômicos associados a falhas de controle. Para isso, amostras de sementes de plantas de leiteira foram coletadas em lavouras de soja RR localizadas em 56 municípios do Estado do RS. Por ocasião das coletas, os agricultores responderam a questionário que abordava o manejo das plantas daninhas na área. Usando-se as sementes coletadas, foram conduzidos dois experimentos em casa de vegetação: no primeiro, avaliou-se a resposta de 86 biótipos ao herbicida glyphosate, aplicado na dose de 2.160 g e.a. ha-1; e, no segundo, a resposta de 73 biótipos ao herbicida imazethapyr, aplicado na dose de 200 g i.a. ha-1. Os resultados obtidos evidenciam que todos os biótipos de leiteira avaliados são suscetíveis ao glyphosate, porém existem biótipos resistentes aos inibidores da ALS. As respostas do questionário indicam que práticas de manejo como uso de subdoses e/ou utilização intensiva do glyphosate e a ausência de rotação de culturas favorecem falhas no controle de leiteira pelo herbicida glyphosate em soja.The intensive use of glyphosate in Roundup Ready® (RR soybean fields in Rio Grande do Sul (RS, in recent years may have selected wild poinsettia (Euphorbia heterophylla biotypes resistant to the herbicide. This scenario will further complicate the management of this species, since evidence remains of the presence of herbicide resistant biotypes also in acetolactate synthase (ALS-inhibitors. Thus, the objectives of this work were to evaluate wild poinsettia's sensitivity to the ALS-inhibiting herbicides and glyphosate; to investigate the distribution of resistant biotypes in the state of RS;and to determine the main agronomic factors associated with control failures. Seeds of wild poinsettia plants that survived glyphosate applications were collected from RR soybean fields located in 56 municipalities in the state of RS. On the occasion, the farmers were interviewed through a questionnaire aiming to collect information on the management of the area. Using the seeds collected, two experiments were conducted under greenhouse conditions. The first evaluated the response of 86 biotypes to glyphosate, applied at the rate of 2.160 g ha-1 while the second experiment evaluated the response of the herbicide imazethapyr to 73 biotypes, applied at a dose of 200 g a.i. ha?1. The results show that all the wild poinsettia biotypes evaluated are susceptible to glyphosate, but some are resistant to ALS-inhibitors. The survey responses indicate that management practices such as the use of sub doses and/or intensive use of glyphosate, as well as lack of crop rotation favor failures in wild poinsettia control by glyphosate in soybean.

  5. Práticas de manejo e a resistência de Euphorbia heterophylla aos inibidores da ALS e tolerância ao glyphosate no Rio Grande do Sul / Management practices x Euphorbia heterophylla resistance to ALS-inhibitors and tolerance to glyphosate in Rio Grande do Sul

    Scientific Electronic Library Online (English)

    L., Vargas; M.A., Nohatto; D., Agostinetto; M.A., Bianchi; J.M., Paula; E., Polidoro; R.E., Toledo.

    2013-06-01

    Full Text Available A utilização intensiva do glyphosate nas lavouras de soja Roundup Ready® (RR) no Rio Grande do Sul (RS), nos últimos anos, pode ter selecionado biótipos de leiteira (Euphorbia heterophylla) resistentes ao herbicida. Esse cenário dificultará ainda mais o manejo da espécie, já que permanecem indícios [...] da presença de biótipos resistentes também em herbicidas inibidores da acetolactato sintase (ALS). Assim, os objetivos deste trabalho foram avaliar a sensibilidade da leiteira a herbicidas inibidores da ALS e ao glyphosate, verificar a distribuição dos biótipos resistentes no RS e determinar os principais fatores agronômicos associados a falhas de controle. Para isso, amostras de sementes de plantas de leiteira foram coletadas em lavouras de soja RR localizadas em 56 municípios do Estado do RS. Por ocasião das coletas, os agricultores responderam a questionário que abordava o manejo das plantas daninhas na área. Usando-se as sementes coletadas, foram conduzidos dois experimentos em casa de vegetação: no primeiro, avaliou-se a resposta de 86 biótipos ao herbicida glyphosate, aplicado na dose de 2.160 g e.a. ha-1; e, no segundo, a resposta de 73 biótipos ao herbicida imazethapyr, aplicado na dose de 200 g i.a. ha-1. Os resultados obtidos evidenciam que todos os biótipos de leiteira avaliados são suscetíveis ao glyphosate, porém existem biótipos resistentes aos inibidores da ALS. As respostas do questionário indicam que práticas de manejo como uso de subdoses e/ou utilização intensiva do glyphosate e a ausência de rotação de culturas favorecem falhas no controle de leiteira pelo herbicida glyphosate em soja. Abstract in english The intensive use of glyphosate in Roundup Ready® (RR) soybean fields in Rio Grande do Sul (RS), in recent years may have selected wild poinsettia (Euphorbia heterophylla) biotypes resistant to the herbicide. This scenario will further complicate the management of this species, since evidence remain [...] s of the presence of herbicide resistant biotypes also in acetolactate synthase (ALS)-inhibitors. Thus, the objectives of this work were to evaluate wild poinsettia's sensitivity to the ALS-inhibiting herbicides and glyphosate; to investigate the distribution of resistant biotypes in the state of RS;and to determine the main agronomic factors associated with control failures. Seeds of wild poinsettia plants that survived glyphosate applications were collected from RR soybean fields located in 56 municipalities in the state of RS. On the occasion, the farmers were interviewed through a questionnaire aiming to collect information on the management of the area. Using the seeds collected, two experiments were conducted under greenhouse conditions. The first evaluated the response of 86 biotypes to glyphosate, applied at the rate of 2.160 g ha-1 while the second experiment evaluated the response of the herbicide imazethapyr to 73 biotypes, applied at a dose of 200 g a.i. ha?1. The results show that all the wild poinsettia biotypes evaluated are susceptible to glyphosate, but some are resistant to ALS-inhibitors. The survey responses indicate that management practices such as the use of sub doses and/or intensive use of glyphosate, as well as lack of crop rotation favor failures in wild poinsettia control by glyphosate in soybean.

  6. Reducing side effects of hiding sensitive itemsets in privacy preserving data mining.

    Science.gov (United States)

    Lin, Chun-Wei; Hong, Tzung-Pei; Hsu, Hung-Chuan

    2014-01-01

    Data mining is traditionally adopted to retrieve and analyze knowledge from large amounts of data. Private or confidential data may be sanitized or suppressed before it is shared or published in public. Privacy preserving data mining (PPDM) has thus become an important issue in recent years. The most general way of PPDM is to sanitize the database to hide the sensitive information. In this paper, a novel hiding-missing-artificial utility (HMAU) algorithm is proposed to hide sensitive itemsets through transaction deletion. The transaction with the maximal ratio of sensitive to nonsensitive one is thus selected to be entirely deleted. Three side effects of hiding failures, missing itemsets, and artificial itemsets are considered to evaluate whether the transactions are required to be deleted for hiding sensitive itemsets. Three weights are also assigned as the importance to three factors, which can be set according to the requirement of users. Experiments are then conducted to show the performance of the proposed algorithm in execution time, number of deleted transactions, and number of side effects. PMID:24982932

  7. Manejo de capim pé-de-galinha em lavouras de soja transgênica resistente ao glifosato / Management of goose grass on transgenic soybean, resistant to glyphosate

    Scientific Electronic Library Online (English)

    André da Rosa, Ulguim; Leandro, Vargas; Dirceu, Agostinetto; Taísa Dal, Magro; Nixon da Rosa, Westendorff; Marcelo Timm, Holz.

    2013-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a resistência de capim pé-de-galinha (Eleusine indica) ao glifosato, em lavouras de soja transgênica; avaliar o efeito de aplicações de glifosato em diferentes estádios de desenvolvimento; identificar práticas agronômicas associadas à seleção de biótipos resiste [...] ntes; e avaliar a eficiência dos herbicidas cletodim, fluazifope-P-butílico, clomazona, glufosinato de amônio e glifosato nas plantas resistentes. Plantas escapes ao tratamento com glifosato foram coletadas em 24 propriedades, no Rio Grande do Sul. As plantas foram cultivadas em casa de vegetação, tendo-se avaliado a sua resistência ao glifosato. Os acessos resistentes foram selecionados e avaliados quanto ao efeito da aplicação do glifosato em diferentes estádios de crescimento e quanto à sensibilidade aos herbicidas. Foi aplicado um questionário aos produtores para identificação das práticas agronômicas associadas às falhas no controle. O controle de E. indica pelo glifosato é mais efetivo com a aplicação em estádios iniciais de desenvolvimento. Práticas agronômicas, como uso contínuo de baixas doses do herbicida, aplicação em estádios de desenvolvimento avançados das plantas daninhas (mais de um afilho) e a ausência de rotação de culturas foram relacionadas às falhas de controle observadas. Os herbicidas cletodim, fluazifope-P-butílico e glufosinato de amônio são alternativas eficientes para o controle de E. indica. Abstract in english The objective of this work was to evaluate the resistance of goose grass (Eleusine indica) to glyphosate application in transgenic soybean crops; evaluate the effect of glyphosate applications in different growth stages; identify the main agronomic practices associated with the selection of resistan [...] t biotypes; and evaluate the effect of the herbicides clethodim, fluazifop-p-butyl, clomazone, glufosinate ammonium, and glyphosate on resistant plants. Plants that survived glyphosate application were collected on 24 properties in the state of Rio Grande do Sul, Brazil. Plants were grown in greenhouse and their resistance to glyphosate was evaluated. The resistant accessions were selected and evaluated as to the effect of glyphosate application on different growth stages and to their sensitivity to the herbicides. A questionnaire was given to producers in order to identify agronomic practices associated with control failures. The control of E. indica by glyphosate is more effective at initial growth stages. Agronomic practices, such as continued use of low doses of glyphosate, application on advanced weed growth stages (more than one tiller), and absence of crop rotation were related to the observed control failures. The herbicides clethodim, fluazifop-p-butyl, and glufosinate ammonium are efficient alternatives to control E. indica.

  8. Manejo de capim pé-de-galinha em lavouras de soja transgênica resistente ao glifosato Management of goose grass on transgenic soybean, resistant to glyphosate

    Directory of Open Access Journals (Sweden)

    André da Rosa Ulguim

    2013-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a resistência de capim pé-de-galinha (Eleusine indica ao glifosato, em lavouras de soja transgênica; avaliar o efeito de aplicações de glifosato em diferentes estádios de desenvolvimento; identificar práticas agronômicas associadas à seleção de biótipos resistentes; e avaliar a eficiência dos herbicidas cletodim, fluazifope-P-butílico, clomazona, glufosinato de amônio e glifosato nas plantas resistentes. Plantas escapes ao tratamento com glifosato foram coletadas em 24 propriedades, no Rio Grande do Sul. As plantas foram cultivadas em casa de vegetação, tendo-se avaliado a sua resistência ao glifosato. Os acessos resistentes foram selecionados e avaliados quanto ao efeito da aplicação do glifosato em diferentes estádios de crescimento e quanto à sensibilidade aos herbicidas. Foi aplicado um questionário aos produtores para identificação das práticas agronômicas associadas às falhas no controle. O controle de E. indica pelo glifosato é mais efetivo com a aplicação em estádios iniciais de desenvolvimento. Práticas agronômicas, como uso contínuo de baixas doses do herbicida, aplicação em estádios de desenvolvimento avançados das plantas daninhas (mais de um afilho e a ausência de rotação de culturas foram relacionadas às falhas de controle observadas. Os herbicidas cletodim, fluazifope-P-butílico e glufosinato de amônio são alternativas eficientes para o controle de E. indica.The objective of this work was to evaluate the resistance of goose grass (Eleusine indica to glyphosate application in transgenic soybean crops; evaluate the effect of glyphosate applications in different growth stages; identify the main agronomic practices associated with the selection of resistant biotypes; and evaluate the effect of the herbicides clethodim, fluazifop-p-butyl, clomazone, glufosinate ammonium, and glyphosate on resistant plants. Plants that survived glyphosate application were collected on 24 properties in the state of Rio Grande do Sul, Brazil. Plants were grown in greenhouse and their resistance to glyphosate was evaluated. The resistant accessions were selected and evaluated as to the effect of glyphosate application on different growth stages and to their sensitivity to the herbicides. A questionnaire was given to producers in order to identify agronomic practices associated with control failures. The control of E. indica by glyphosate is more effective at initial growth stages. Agronomic practices, such as continued use of low doses of glyphosate, application on advanced weed growth stages (more than one tiller, and absence of crop rotation were related to the observed control failures. The herbicides clethodim, fluazifop-p-butyl, and glufosinate ammonium are efficient alternatives to control E. indica.

  9. Seed Germination Differences Between Glyphosate-Resistant and -Susceptible Italian Ryegrass Populations

    Science.gov (United States)

    Italian ryegrass tolerant to glyphosate is becoming a major weed problem in glyphosate-resistant crops. The effects of temperature, light, pH, salt and osmotic stress, shikimic acid, and planting depth on germination of glyphosate-tolerant (T) and susceptible (S) Italian ryegrass populations were st...

  10. Glyphosate-Resistant Palmer Amaranth (Amaranthus palmeri) Spreads in the Southern United States (U.S.)

    Science.gov (United States)

    Glyphosate (N-phosphonomethyl glycine) is an exceptionally broad-spectrum herbicide that was first registered for use in 1974. Glyphosate is used mainly in conjunction with transgenic, glyphosate-resistant soybean, canola (Brassica napus), cotton (Gossypium hirsutum), and corn (Zea mays) cultivars, ...

  11. Varying tolerance to glyphosate in a population of Palmer amaranth with low epsps copy number

    Science.gov (United States)

    A Palmer amaranth population (seeds collected in the year 2000; Washington Co., MS) suspected to be susceptible to glyphosate was examined as a population and as individual plants and found to exhibit varying tolerance or resistance to glyphosate. Whole plant spraying of glyphosate (0.84 kg ha-1) t...

  12. Effect of reducing groundwater on the retardation of redox-sensitive radionuclides

    OpenAIRE

    Rose TP; Zavarin M; Hu QH

    2008-01-01

    Abstract Laboratory batch sorption experiments were used to investigate variations in the retardation behavior of redox-sensitive radionuclides. Water-rock compositions were designed to simulate subsurface conditions at the Nevada Test Site (NTS), where a suite of radionuclides were deposited as a result of underground nuclear testing. Experimental redox conditions were controlled by varying the oxygen content inside an enclosed glove box and by adding reductants into the testing solutions. U...

  13. Skeletal troponin C reduces contractile sensitivity to acidosis in cardiac myocytes from transgenic mice.

    OpenAIRE

    Metzger, J. M.; Parmacek, M S; Barr, E.; Pasyk, K; Lin, W I; Cochrane, K L; Field, L J; Leiden, J M

    1993-01-01

    Depressed contractile function plays a primary role in the pathophysiology of acute myocardial ischemia. Intracellular acidification is an important factor underlying the inhibition of force production in the ischemic myocardium. The effect of acidosis to depress contractility is markedly greater in cardiac as compared to skeletal muscle; however, the molecular basis of this difference in sensitivity to acidosis is not clearly understood. In this report, we describe transgenic mice that expre...

  14. Reduced baroreflex sensitivity in alcoholic cirrhosis: relations to hemodynamics and humoral systems

    DEFF Research Database (Denmark)

    Møller, Søren; Iversen, Jens S; Henriksen, Jens H; Bendtsen, Flemming

    2007-01-01

    In cirrhosis, arterial vasodilatation leads to central hypovolemia and activation of the sympathetic nervous and renin-angiotensin-aldosterone systems. As the liver disease and circulatory dysfunction may affect baroreflex sensitivity (BRS), we assessed BRS in a large group of patients with cirrhosis and in controls who were all supine and some after 60 degrees passive head-up and 30 degrees head-down tilting in relation to central hemodynamics and activity of the sympathetic nervous and renin-a...

  15. Pulverização de glyphosate utilizando solução de uréia + sulfato de amônio

    Directory of Open Access Journals (Sweden)

    Saul Jorge Pinto Carvalho

    2012-04-01

    Full Text Available Diversos experimentos têm sido realizados com intuito de elevar a eficácia do herbicida glyphosate na dessecação de plantas daninhas, incluindo-se o uso de sulfato de amônio ou ureia como adjuvantes. Em termos fisiológicos, existem explicações para o efeito complementar destes produtos quando adicionados concomitantemente à calda herbicida. Desta forma, três experimentos foram desenvolvidos em campo com o objetivo de avaliar a eficácia do herbicida glyphosate para dessecação de espécies de plantas daninhas utilizando solução de fertilizantes nitrogenados como veículos de pulverização. Foram avaliados seis tratamentos, sendo estes: aplicação de glyphosate (540 g e.a. ha-1 utilizando água, solução de sulfato de amônio – SA (15 g L-1, solução de uréia – U (5 g L-1, solução de U+SA (2,5 + 7,5 g L-1 como veículos de pulverização, glyphosate a 1080 g e.a. ha-1 aplicado com água, e testemunha sem aplicação. Avaliou-se a eficácia dos tratamentos sobre comunidade mista de plantas daninhas, Brachiaria decumbens e Sorghum halepense. O uso de solução de fertilizantes nitrogenados como veículo para pulverização do glyphosate não elevou o controle de B. decumbens. A menor dose do herbicida glyphosate teve maior eficácia sobre a comunidade mista de plantas daninhas e sobre S. halepense devido à pulverização com solução de SA (15 g L-1 ou de U+SA (2,5 + 7,5 g L-1. Os resultados positivos obtidos pela aplicação de glyphosate com fertilizantes nitrogenados também foram observados para a redução de massa fresca da comunidade mista e para massa fresca e seca de S. halepense.

  16. Technical Note: Method of Morris effectively reduces the computational demands of global sensitivity analysis for distributed watershed models

    Science.gov (United States)

    Herman, J. D.; Kollat, J. B.; Reed, P. M.; Wagener, T.

    2013-07-01

    The increase in spatially distributed hydrologic modeling warrants a corresponding increase in diagnostic methods capable of analyzing complex models with large numbers of parameters. Sobol' sensitivity analysis has proven to be a valuable tool for diagnostic analyses of hydrologic models. However, for many spatially distributed models, the Sobol' method requires a prohibitive number of model evaluations to reliably decompose output variance across the full set of parameters. We investigate the potential of the method of Morris, a screening-based sensitivity approach, to provide results sufficiently similar to those of the Sobol' method at a greatly reduced computational expense. The methods are benchmarked on the Hydrology Laboratory Research Distributed Hydrologic Model (HL-RDHM) over a six-month period in the Blue River watershed, Oklahoma, USA. The Sobol' method required over six million model evaluations to ensure reliable sensitivity indices, corresponding to more than 30 000 computing hours and roughly 180 gigabytes of storage space. We find that the method of Morris is able to correctly screen the most and least sensitive parameters with 300 times fewer model evaluations, requiring only 100 computing hours and 1 gigabyte of storage space. The method of Morris proves to be a promising diagnostic approach for global sensitivity analysis of highly parameterized, spatially distributed hydrologic models.

  17. Subacute toxicity of copper and glyphosate and their interaction to earthworm (Eisenia fetida)

    International Nuclear Information System (INIS)

    Glyphosate (GPS) and copper (Cu) are common pollutants in soils, and commonly co-exist. Due to the chemical structure of GPS, it can form complexes of heavy metals and interface their bioavailability in soil environment. In order to explore the interactions between GPS and Cu, subacute toxicity tests of Cu and GPS on soil invertebrate earthworms (Eisenia fetida) were conducted. The relative weight loss and whole-worm metal burdens increased significantly with the increasing exposure concentration of Cu, while the toxicity of GPS was insignificant. The joint toxicity data showed that the relative weight loss and the uptake of Cu, as well as the superoxide dismutase, catalase and malondialdehyde activities, were significantly alleviated in the present of GPS, which indicated that GPS could reduce the toxicity and bioavailability of Cu in the soil because of its strong chelating effects. Highlights: •Cu markedly increased the weight loss ratio of earthworm. •Cu decreased the cocoon production of earthworm. •The toxicity of GPS on earthworm was insignificant. •The presence of GPS could reduce the toxicity of Cu on earthworm. -- The presence of glyphosate could reduce the toxicity and bioavailability of Cu in the soil because of its strong chelating effects

  18. Replacing Fish Oil with Vegetable Oils in Salmon Feed Increases Hepatic Lipid Accumulation and Reduces Insulin Sensitivity in Mice

    DEFF Research Database (Denmark)

    MidtbØ, Lisa Kolden

    2013-01-01

    Background: Due to a growing global aquaculture production, fish oil (FO) and fish meal (FM) are partly replaced with vegetable ingredients in aqua feed for Atlantic salmon. These replacements in the feed lead to an altered fatty acid composition in the salmon fillet. We aimed to investigate how these changes affects obesity development and insulin sensitivity in mice eating the salmon. In addition, we wanted to investigate how the background diet affects the antiobesity effect of FO. Results: Western diets (WDs) were produced containing salmon fed either FO (WD-FO), or with partly replacement (80%) of FO with different vegetable oils (VOs); rape seed oil (WDRO), olive oil (WD-OO) or soybean oil (WD-SO). These diets were given to C57BL/6J mice, and mice had higher hepatic lipid accumulation and lower insulin sensitivity when given WD-SO compared with WD-FO. Mice given WD-SO had higher hepatic levels of diacylglycerol (DAG), ceramides and arachidonic acid (AA)-derived oxylipins compared with mice fed WD-FO. In addition, C57BL/6J mice were fed fish oil-enriched diets with different carbohydrate sources, and we observed that sucrose dose-dependently abrogate the antiobesity effect of fish oil. High-GI starch had a stronger effect on reducing the antiobesity effect of FO compared with low-GI starch. Conclusions: In summary, our results demonstrate that the background diet affects the antiobesity effect of FO and that replacement of FO with SO in aqua feed increased hepatic lipid accumulation and reduces insulin sensitivity. Elevated hepatic levels of DAG, ceramides and AA-derived oxylipins might be a link between the observed hepatic lipid accumulation and the reduced insulin sensitivity.

  19. Relationship between radiation dose and reduced X-ray sensitivity surrounding breast region using CR stimulable phosphor plate for mammography

    Science.gov (United States)

    Nishide, Hiroko; Kodera, Yoshie

    2015-03-01

    Computed radiography (CR) systems use a photostimulable phosphor plate (imaging plate ; IP) as a sensor for digital mammography. In clinical mammography, breast is almost exposed same region of IP, and therefor, direct x-ray regions surrounding suffer from reduced x-ray sensitivity. Consequently, the difference in x-ray sensitivity between the breast regions and the unattenuated x-ray region was obtained. However, radiation dose quantity that reduces x-ray sensitivity is not known. In this study, we imaged a breast phantom under fixed conditions, and subsequently, we investigated the pixel value differences between the breast region and the unattenuated x-ray regions. We measured the entrance air-kerma using 550 sensing elements of glass dosimeter, 22x25 lines, that were placed at the surface of the cassette including the IP. In order to measure the x-ray sensitivity, pre- and post-exposure breast phantom images were acquired after 500, 1,000, 1,350, and 1,500 trials. The pixel values were measured at four points; in the breast region and in the unattenuated x-ray region. The ratio of these pixel values was compared with the cumulative exposure dose. The ratio was nearly constant until 1,000 trials, but a significant reduction was observed after 1,350 trials. Further, in the image obtained after 1,500th trials, the shape of breast phantom could be observed. This image supports the fact that the x-ray sensitivity was lowered in the unattenuated x-ray region. The difference in the pixel value between the breast region and the unattenuated x-ray region was obtained over 1,000 exposures at 100,000 mAs.

  20. Adsorção de glifosato sobre solos e minerais / Adsorption of glyphosate on soils and minerals

    Scientific Electronic Library Online (English)

    Luís R. M., Toni; Henrique de, Santana; Dimas A. M., Zaia.

    2006-07-01

    Full Text Available [...] Abstract in english Glyphosate, an enzyme inhibitor herbicide, has been widely used around the world in agriculture. Dr. John Franz from Monsanto Corporation (USA) discovered glyphosate in 1970. It has been showed that glyphosate is strongly adsorbed by inorganic soil components especially aluminium and iron oxides, an [...] d the phosphate group is involved in this interaction. The inactivation of glyphosate in soils can last for days or even months depending on soil characteristics. The addition of phosphate from fertilizers can displace glyphosate from the soils and this could be the cause of decreased productivity of some crops.

  1. Adsorção de glifosato sobre solos e minerais Adsorption of glyphosate on soils and minerals

    Directory of Open Access Journals (Sweden)

    Luís R. M. Toni

    2006-07-01

    Full Text Available Glyphosate, an enzyme inhibitor herbicide, has been widely used around the world in agriculture. Dr. John Franz from Monsanto Corporation (USA discovered glyphosate in 1970. It has been showed that glyphosate is strongly adsorbed by inorganic soil components especially aluminium and iron oxides, and the phosphate group is involved in this interaction. The inactivation of glyphosate in soils can last for days or even months depending on soil characteristics. The addition of phosphate from fertilizers can displace glyphosate from the soils and this could be the cause of decreased productivity of some crops.

  2. Reduced sensitivity to emotional prosody in congenital amusia rekindles the musical protolanguage hypothesis.

    Science.gov (United States)

    Thompson, William Forde; Marin, Manuela M; Stewart, Lauren

    2012-11-13

    A number of evolutionary theories assume that music and language have a common origin as an emotional protolanguage that remains evident in overlapping functions and shared neural circuitry. The most basic prediction of this hypothesis is that sensitivity to emotion in speech prosody derives from the capacity to process music. We examined sensitivity to emotion in speech prosody in a sample of individuals with congenital amusia, a neurodevelopmental disorder characterized by deficits in processing acoustic and structural attributes of music. Twelve individuals with congenital amusia and 12 matched control participants judged the emotional expressions of 96 spoken phrases. Phrases were semantically neutral but prosodic cues (tone of voice) communicated each of six emotional states: happy, tender, afraid, irritated, sad, and no emotion. Congenitally amusic individuals were significantly worse than matched controls at decoding emotional prosody, with decoding rates for some emotions up to 20% lower than that of matched controls. They also reported difficulty understanding emotional prosody in their daily lives, suggesting some awareness of this deficit. The findings support speculations that music and language share mechanisms that trigger emotional responses to acoustic attributes, as predicted by theories that propose a common evolutionary link between these domains. PMID:23112175

  3. Reduced sensitivity to emotional prosody in congenital amusia rekindles the musical protolanguage hypothesis

    DEFF Research Database (Denmark)

    Thompson, William Forde; Marin, Manuela M

    2012-01-01

    A number of evolutionary theories assume that music and language have a common origin as an emotional protolanguage that remains evident in overlapping functions and shared neural circuitry. The most basic prediction of this hypothesis is that sensitivity to emotion in speech prosody derives from the capacity to process music. We examined sensitivity to emotion in speech prosody in a sample of individuals with congenital amusia, a neurodevelopmental disorder characterized by deficits in processing acoustic and structural attributes of music. Twelve individuals with congenital amusia and 12 matched control participants judged the emotional expressions of 96 spoken phrases. Phrases were semantically neutral but prosodic cues (tone of voice) communicated each of six emotional states: happy, tender, afraid, irritated, sad, and no emotion. Congenitally amusic individuals were significantly worse than matched controls at decoding emotional prosody, with decoding rates for some emotions up to 20% lower than that of matched controls. They also reported difficulty understanding emotional prosody in their daily lives, suggesting some awareness of this deficit. The findings support speculations that music and language share mechanisms that trigger emotional responses to acoustic attributes, as predicted by theories that propose a common evolutionary link between these domains.

  4. Momento da chuva após a aplicação e a eficácia dos herbicidas sulfosate e glyphosate aplicados em diferentes formulações / Rainfastness and glyphosate and sulfosate efficacy using different formulations

    Scientific Electronic Library Online (English)

    A.F.F., Pedrinho Júnior; G., Martini; G.V., Felici; F.M., Piva; J.C., Durigan.

    2002-04-01

    Full Text Available Com o objetivo de estudar a influência da chuva sobre o desempenho dos herbicidas sulfosate e glyphosate em diferentes formulações, foram conduzidos dois experimentos, um no inverno de 2000 e outro no verão de 2001, na Fazenda Experimental de Ensino e Pesquisa da Faculdade de Ciências Agrárias e Vet [...] erinárias, Campus de Jaboticabal-SP. Os experimentos foram instalados segundo o delineamento experimental de blocos ao acaso, com quatro repetições, no arranjo fatorial de 4x5+1, ou seja, quatro tratamentos de herbicidas, cinco períodos sem chuva após a aplicação e uma testemunha, que não recebeu chuva. As formulações de glyphosate foram: SAqC (1,0 L ha-1), GrDA (0,5 kg ha-1), SAqC Transorb (0,75 L ha-1), mais o sulfosate SAqC (1,09 L ha¹). Os períodos sem chuva após a aplicação foram de 1, 2, 4, 6 e > 48 horas. Os herbicidas foram aplicados em pós-emergência das plantas daninhas, utilizando-se de um pulverizador costal, à pressão constante (mantida por ar comprimido) de 30 lbf pol-2. A chuva foi simulada com um sistema de irrigação por aspersão. A lâmina de água variou entre 18 e 19 mm. Em ambas as épocas, a chuva simulada foi prejudicial à ação dos herbicidas, principalmente quando feita nos menores intervalos após a aplicação. Os sintomas de fitointoxicação apareceram mais rapidamente no verão. A formulação Transorb, comercializada como não sendo afetada pela chuva uma hora após a aplicação, não teve o desempenho esperado, tanto no inverno quanto no verão, para períodos de até seis horas sem chuva após a aplicação. O sulfosate apresentou o melhor controle geral das plantas avaliadas, quando se simulou chuva após seis horas, em ambas as épocas. A formulação GrDA foi a mais afetada pela ação da chuva em ambas as épocas. Abstract in english Two field assays were carried out to evaluate the rainfall effects on sulfosate and glyphosate herbicide activity, using different formulations, under two growing seasons (winter and summer). The experiments were conducted at the FCAV/UNESP Experimental Station, Jaboticabel, Brazil, during 2000/01. [...] The formulations were glyphosate SA (1.0 L ha-1), WG (0.5 L ha-1), Transorb (0.75 L ha-1) and sulfosate SA (1.09 L ha-1). In the field, all the trials were arranged in a randomized block experimental design, with four replications. The treatments were arranged in factorial design 5 x 4 + 1 factors, with five periods between the herbicide spraying and the rain incidence (1, 2, 4, 6 and > 48 h), plus one control treatment. The herbicide treatments were applied using a back spraying, with six nozzles DG 11002, spaced by 0.5 m, at 30 p.s.i. constant pression. Artificial rain was provided by a top irrigation system raining 18-19 mm during one hour. The artificial rain reduced glyphosate action, mainly in the shorter periods between herbicide application and the rain incidence. The herbicide symptoms appeared quicker in the summer trials. The Transorb formulation (advertised as not affected by rain one hour after spraying) had the phytointoxication symptoms reduced by the rain up to six hours after spraying, both in the summer and winter. The herbicide sulfosate promoted better control when the rain occurred six hours after spraying, in both seasons.

  5. Momento da chuva após a aplicação e a eficácia dos herbicidas sulfosate e glyphosate aplicados em diferentes formulações Rainfastness and glyphosate and sulfosate efficacy using different formulations

    Directory of Open Access Journals (Sweden)

    A.F.F. Pedrinho Júnior

    2002-04-01

    Full Text Available Com o objetivo de estudar a influência da chuva sobre o desempenho dos herbicidas sulfosate e glyphosate em diferentes formulações, foram conduzidos dois experimentos, um no inverno de 2000 e outro no verão de 2001, na Fazenda Experimental de Ensino e Pesquisa da Faculdade de Ciências Agrárias e Veterinárias, Campus de Jaboticabal-SP. Os experimentos foram instalados segundo o delineamento experimental de blocos ao acaso, com quatro repetições, no arranjo fatorial de 4x5+1, ou seja, quatro tratamentos de herbicidas, cinco períodos sem chuva após a aplicação e uma testemunha, que não recebeu chuva. As formulações de glyphosate foram: SAqC (1,0 L ha-1, GrDA (0,5 kg ha-1, SAqC Transorb (0,75 L ha-1, mais o sulfosate SAqC (1,09 L ha¹. Os períodos sem chuva após a aplicação foram de 1, 2, 4, 6 e > 48 horas. Os herbicidas foram aplicados em pós-emergência das plantas daninhas, utilizando-se de um pulverizador costal, à pressão constante (mantida por ar comprimido de 30 lbf pol-2. A chuva foi simulada com um sistema de irrigação por aspersão. A lâmina de água variou entre 18 e 19 mm. Em ambas as épocas, a chuva simulada foi prejudicial à ação dos herbicidas, principalmente quando feita nos menores intervalos após a aplicação. Os sintomas de fitointoxicação apareceram mais rapidamente no verão. A formulação Transorb, comercializada como não sendo afetada pela chuva uma hora após a aplicação, não teve o desempenho esperado, tanto no inverno quanto no verão, para períodos de até seis horas sem chuva após a aplicação. O sulfosate apresentou o melhor controle geral das plantas avaliadas, quando se simulou chuva após seis horas, em ambas as épocas. A formulação GrDA foi a mais afetada pela ação da chuva em ambas as épocas.Two field assays were carried out to evaluate the rainfall effects on sulfosate and glyphosate herbicide activity, using different formulations, under two growing seasons (winter and summer. The experiments were conducted at the FCAV/UNESP Experimental Station, Jaboticabel, Brazil, during 2000/01. The formulations were glyphosate SA (1.0 L ha-1, WG (0.5 L ha-1, Transorb (0.75 L ha-1 and sulfosate SA (1.09 L ha-1. In the field, all the trials were arranged in a randomized block experimental design, with four replications. The treatments were arranged in factorial design 5 x 4 + 1 factors, with five periods between the herbicide spraying and the rain incidence (1, 2, 4, 6 and > 48 h, plus one control treatment. The herbicide treatments were applied using a back spraying, with six nozzles DG 11002, spaced by 0.5 m, at 30 p.s.i. constant pression. Artificial rain was provided by a top irrigation system raining 18-19 mm during one hour. The artificial rain reduced glyphosate action, mainly in the shorter periods between herbicide application and the rain incidence. The herbicide symptoms appeared quicker in the summer trials. The Transorb formulation (advertised as not affected by rain one hour after spraying had the phytointoxication symptoms reduced by the rain up to six hours after spraying, both in the summer and winter. The herbicide sulfosate promoted better control when the rain occurred six hours after spraying, in both seasons.

  6. Glyphosate in post-emergence at Roundup Ready® soybean

    Directory of Open Access Journals (Sweden)

    Rodrigo Lopes Ferreira

    2013-08-01

    Full Text Available Generation of RR® soybean genotypes allowed many farmers adopted the use of glyphosate in weed management in post-emergence in cerrado. However, information about the use of this technology on soybean crop growth in “cerrado” region is important in order to obtain desired yields. Thus, the objective of this study was to evaluate the effects of glyphosate application in post-emergence condition over agronomic characteristics and over RR soybean nodulation. The trial was conducted in randomized blocks experimental design in factorial scheme (3x4+1 with three replications corresponding to three glyphosate doses (960; 1,920 and  2,880 g a.e ha-1 associated to four application phenological stages of application (V1, V2, V3 and V1+V4 plus a treatment without herbicide application (check. The following characteristics were evaluated: grain yield, mass of a thousand grain, plant height, phytointoxication, leaf closing, root dry matter and length, besides dry mass and nodules viability. Results revealed that the dose and stage of glyphosate application did not affect the nodulation, agronomic characteristics and grain yield. The highest percentage of phytointoxication and lowest leaf closing were observed at 2,880 g a.e. ha-1 glyphosate dose sprayed on phenological stages V1+V4, without affecting nodulation and grain yield.

  7. Eficácia de glyphosate em plantas de cobertura Efficacy of glyphosate in cover crops

    Directory of Open Access Journals (Sweden)

    P.C. Timossi

    2006-09-01

    Full Text Available Objetivou-se comparar a eficácia de três dosagens do herbicida glyphosate para a dessecação de Brachiaria decumbens, B. brizantha cv. Marandu e vegetação espontânea, visando a adoção do sistema plantio direto. Utilizou-se delineamento experimental de blocos ao acaso, num esquema fatorial 3 x 3, com quatro repetições. Testaram-se três tipos de cobertura vegetal e três dosagens de glyphosate (1,44, 2,16 e 2,88 kg ha-1. Aos 7, 14, 21 e 28 dias após a aplicação (DAA, foram feitas avaliações visuais da porcentagem de controle das coberturas vegetais e, aos 45 DAA, avaliações visuais da porcentagem de reinfestação da área. Conclui-se que, para as espécies que compunham a vegetação espontânea, o uso de 1,44 kg ha-1 proporcionou bom controle, sem no entanto evitar rebrotes de Digitaria insularis. Para as braquiárias, a mesma taxa de controle foi observada a partir de 2,16 kg ha-1. A camada de palha das braquiárias sobre o solo não foi capaz de suprimir a emergência de Cyperus rotundus, Alternanthera tenella, Raphanus raphanistrum, Bidens pilosa e Euphorbia heterophylla.This work aimed to compare rates of glyphosate to desiccate Brachiaria decumbens, B. brizantha cv. Marandu and spontaneous plants (weeds, aiming to adopt the no-tillage system. A randomized block experimental design in a factorial scheme was used (3x3, with four replications. The factors consisted of three species of cover crops and three rates of glyphosate (1.44, 2.16 and 2.88 kg ha-1. At 7, 14, 21 and 28 days after application of the herbicide, visual evaluations of the percentage of cover crop control were carried out and at 45 days of the reinfestation percentage of the area. It was concluded that the spontaneous plants presented a good control at 1.44 kg ha-1, without, however, preventing Digitaria insularis sprouts. The same control rate starting at 2.16 kg ha-1 was observed for the Brachiaria species. The straw layer of these cover crops on the soil was not able to suppress the emergence of Cyperus rotundus, Alternanthera tenella, Raphanus raphanistrum, Bidens pilosa and Euphorbia heterophylla.

  8. Aluminum sulfate significantly reduces the skin test response to common allergens in sensitized patients

    Directory of Open Access Journals (Sweden)

    Grier Thomas J

    2006-02-01

    Full Text Available Abstract Background Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens. Methods Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study. Results Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated. Conclusion Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen.

  9. No fitness cost of glyphosate resistance endowed by massive EPSPS gene amplification in Amaranthus palmeri.

    Science.gov (United States)

    Vila-Aiub, Martin M; Goh, Sou S; Gaines, Todd A; Han, Heping; Busi, Roberto; Yu, Qin; Powles, Stephen B

    2014-04-01

    Amplification of the EPSPS gene has been previously identified as the glyphosate resistance mechanism in many populations of Amaranthus palmeri, a major weed pest in US agriculture. Here, we evaluate the effects of EPSPS gene amplification on both the level of glyphosate resistance and fitness cost of resistance. A. palmeri individuals resistant to glyphosate by expressing a wide range of EPSPS gene copy numbers were evaluated under competitive conditions in the presence or absence of glyphosate. Survival rates to glyphosate and fitness traits of plants under intra-specific competition were assessed. Plants with higher amplification of the EPSPS gene (53-fold) showed high levels of glyphosate resistance, whereas less amplification of the EPSPS gene (21-fold) endowed a lower level of glyphosate resistance. Without glyphosate but under competitive conditions, plants exhibiting up to 76-fold EPSPS gene amplification exhibited similar height, and biomass allocation to vegetative and reproductive organs, compared to glyphosate susceptible A. palmeri plants with no amplification of the EPSPS gene. Both the additive effects of EPSPS gene amplification on the level of glyphosate resistance and the lack of associated fitness costs are key factors contributing to EPSPS gene amplification as a widespread and important glyphosate resistance mechanism likely to become much more evident in weed plant species. PMID:24385093

  10. Glyphosate biodegradation and potential soil bioremediation by Bacillus subtilis strain Bs-15.

    Science.gov (United States)

    Yu, X M; Yu, T; Yin, G H; Dong, Q L; An, M; Wang, H R; Ai, C X

    2015-01-01

    Glyphosate and glyphosate-containing herbicides have an adverse effect on mammals, humans, and soil microbial ecosystems. Therefore, it is important to develop methods for enhancing glyphosate degradation in soil through bioremediation. We investigated the potential of glyphosate degradation and bioremediation in soil by Bacillus subtilis Bs-15. Bs-15 grew well at high concentrations of glyphosate; the maximum concentration tolerated by Bs-15 reached 40,000 mg/L. The optimal conditions for bacterial growth and glyphosate degradation were less than 10,000 mg/L glyphosate, with a temperature of 35°C and a pH of 8.0. Optimal fermentation occurred at 180 rpm for 60 h with an inoculum ratio of 4%. Bs-15 degraded 17.65% (12 h) to 66.97% (96 h) of glyphosate in sterile soil and 19.01% (12 h) to 71.57% (96 h) in unsterilized soil. Using a BIOLOG ECO plate test, we observed no significant difference in average well color development values between the soil inoculated with Bs-15 and the control soil before 72 h, although there was a significant difference (P glyphosate-containing herbicides, increasing the microbial functional diversity in glyphosate-contaminated soils and thus enhancing the bioremediation of glyphosate-contaminated soils. PMID:26600533

  11. Herbicidas para o controle de plantas voluntárias de soja resistentes ao glyphosate

    Directory of Open Access Journals (Sweden)

    Dayene Bueno Cruvinel Lima

    2011-04-01

    Full Text Available Este trabalho objetivou avaliar a eficácia de herbicidas no controle de plantas voluntárias de soja resistente ao glyphosate. O ensaio foi conduzido a campo utilizando o delineamento de blocos casualizados, em esquema fatorial 6x9, com quatro repetições, sendo o primeiro fator seis variedades de soja resistentes ao herbicida glyphosate (BRS Favorita RR®, BRS Valiosa RR®, CD 219 RR®, M-SOY 7908 RR®, P98Y11® e P98R31® e o segundo herbicidas aplicados isolados ou em mistura (2,4-D, 2,4-D + glyphosate, metsulfuron-methyl, metsulfuron-metyl + glyphosate, [MSMA + diuron], [MSMA + diuron] + glyphosate, [paraquat + diuron], [paraquat + diuron] + glyphosate e uma testemunha sem herbicida. Os tratamentos [MSMA + diuron] e [MSMA + diuron] + glyphosate apresentaram controle eficaz apenas para CD 219 RR®. Metsulfuron-methyl + glyphosate apresentou eficácia no controle da M-SOY 7908 RR®, P98Y11®, P98R31®, BRS Favorita RR® e CD 219 RR®; assim como a cultivar BRS Valiosa RR® foi a mais tolerante a esse tratamento. A adição de glyphosate não acarretou efeitos antagônicos na eficácia dos herbicidas, porém potencializou a ação do metsulfuron-methyl. Os herbicidas [paraquat + diuron] e 2,4-D foram eficazes no controle da soja RR. Houve diferenças na sensibilidade das variedades aos herbicidas metsulfuron-methyl, metsulfuron-methyl + glyphosate, [MSMA + diuron] e [MSMA + diuron] + glyphosate.

  12. Efficiency of the application of the mixture of glyphosate with saflufenacil on Brachiaria decumbens plants

    Directory of Open Access Journals (Sweden)

    Juliana Roberta Gobi Queiroz

    2014-04-01

    Full Text Available The aim of this work was to investigate the synergism or antagonism of glyphosate with and without mixing with saflufenacil to control B. decumbens. The following treatments were evaluated: glyphosate (1.080; glyphosate + saflufenacil + Dash (1,080 + 24.5 + 0.5 % v/v; glyphosate + 2,4-D (1,080 + 720; glyphosate (1,440; glyphosate + saflufenacil + Dash (1,440 + 24.5 + 0.5% v/v; glyphosate + 2,4-D (1,440 + 720; saflufenacil + Dash (24.5 + 0.5 v/v; 2,4-D (720, doses in g a.i./e.a. ha-1. The efficiency control of Brachiaria decumbens was evaluated at different times: 3, 7, 14, 21, 28, 35, 42 and 49 days after application (DAA, with basis on phytotoxicity symptoms, using the scale of 0 % to 100%. The results were submitted to the F test and the average values were compared using Tukey test at 5 % probability. The herbicide glyphosate applied isolated at both tested doses, or mixed with saflufenacil, provided excellent control of B. decumbens after 14 days. Saflufenacil and 2,4-D when applied isolated without the presence of glyphosate were ineffective in controlling plants. The control of B. decumbens provided by mixtures of glyphosate with 2,4-D and saflufenacil was similar to the application of glyphosate isolated. Mixtures showed no synergism or antagonism on the control of B. decumbens plants.

  13. Leaching of Glyphosate and Aminomethylphosphonic Acid from an Agricultural Field over a Twelve-Year Period

    DEFF Research Database (Denmark)

    Norgaard, Trine; Moldrup, Per

    2014-01-01

    The globally-used herbicide glyphosate (N-(phosphonomethyl)glycine) and its most frequently detected metabolite, aminomethylphosphonic acid (AMPA), were studied in a unique 12-year field-scale monitoring program. The leaching of glyphosate, AMPA, and soil particles were studied in a shallow drainage system beneath a 1.26 ha field. Five annual glyphosate applications were applied with different autumn application dates. Solute mass flux from the drain system following the five glyphosate applications were compared to determine how different factors affect the leaching of glyphosate, AMPA, and particles. Glyphosate and AMPA leaching were highly event driven, controlled by the time and intensity of the first precipitation event after glyphosate application. A high similarity in time-accumulated curves for drainage and leached pesticide masses suggests near-constant drainage and leaching rates for approximately 150 days. There was no clear relationship between particle-facilitated transport and the transport of glyphosate or AMPA. However, soil particles, glyphosate, and AMPA, all showed distinct, simultaneous concentration curves, indicating common dominant transport mechanisms. Also, soil- water content at the time of application and the level of the groundwater table relative to the drain depth was essential for whether solutes were detected in the drainage runoff. We present a leaching risk chart to illustrate the dependence of glyphosate, AMPA, and soil particle leaching based on precipitation intensity and the timing of rain events after glyphosate application.

  14. Shape-controlled ceria-reduced graphene oxide nanocomposites toward high-sensitive in situ detection of nitric oxide.

    Science.gov (United States)

    Hu, Fang Xin; Xie, Jia Le; Bao, Shu Juan; Yu, Ling; Li, Chang Ming

    2015-08-15

    Nitric oxide (NO) is an important signal molecule released by most cancer cells under drug stimulation or/and disease development but it is extremely challenging to in situ while real-time sensitively detect NO due to its large diffusivity, low concentration and fast decay. Herein, shape-controlled reduced graphene oxide nanocomposing with ceria (rGO-CeO2) was synthesized via hydrothermal reaction to construct a highly sensitive real-time sensing platform for NO detection. The crystal shape of CeO2 nanoparticles in rGO-CeO2 composites significantly affects the sensing performance of rGO-CeO2, of which the regular hexagonal nanocrystal CeO2 achieves the highest sensitivity (1676.06 mA cm(-2) M(-1)), a wide dynamic range (18.0 nM to 5.6 µM) and a low detection limit (9.6 nM). This attributes to a synergical effect from high catalytic activity of the specifically shaped CeO2 nanocrystal and good conductivity/high surface area of rGO. This work demonstrates a way by rationally compose individual merit components while well control the nanostructure for a superior synergistic effect to build a smart sensing platform, while offering a great application potential to sensitively real-time detect NO released from living cells for diagnosis or/and studies of complicated biological processes. PMID:25840016

  15. Glyphosate translocation in hairy fleabane (Conyza bonariensis) biotypes / Translocação do glyphosate em biótipos de buva (Conyza bonariensis)

    Scientific Electronic Library Online (English)

    E.A., Ferreira; L., Galon; I., Aspiazú; A.A., Silva; G., Concenço; A.F., Silva; J.A., Oliveira; L., Vargas.

    Full Text Available Objetivou-se com este trabalho avaliar a translocação do glyphosate em plantas de C. bonariensis resistentes e suscetíveis a esse herbicida. Para isso aplicou-se o 14C-glyphosate em mistura com glyphosate comercial (800 g ha-1) sobre o centro da face adaxial da folha do terceiro nó, utilizando-se um [...] a microsseringa, adicionando-se 10 µL da calda com atividade específica de 1.400 Bq, aos 45 dias após a emergência da buva. A concentração de glyphosate translocado na planta foi avaliada em intervalos de tempo de 6, 12, 36 e 72 horas após a aplicação, na folha de aplicação, no caule, nas raízes e nas folhas. Dez horas após a aplicação dos tratamentos (HAT) avaliou-se também a distribuição do produto na folha de aplicação, dividida em base, centro e ápice. As avaliações foram realizadas por meio da medição da radiação emitida pelo 14C-glyphosate, em espectrômetro de cintilação líquida. Maior retenção de glyphosate foi observada na folha tratada do biótipo resistente, aproximadamente 90 % do total absorvido até as 72 horas. No biótipo suscetível esse valor foi de cerca de 70 % no mesmo período. Nas folhas, no caule e nas raízes, a maior concentração do glyphosate absorvido foi encontrada no biótipo suscetível, indicando maior eficiência de translocação neste biótipo. No biótipo resistente o herbicida se acumulou em maior quantidade no ápice e no centro da folha de aplicação e no suscetível observou-se maior acúmulo na base e no centro da mesma folha. Desta forma, pode-se afirmar que o mecanismo de resistência está relacionado à translocação diferencial deste herbicida nos biótipos. Abstract in english The objective of this work was to evaluate the translocation of glyphosate in C. bonariensis plants resistant and susceptible to that herbicide. The 14C-glyphosate was mixed with commercial gyhphosate (800 g ha-1) and applied on the center of the adaxial face of a third node leaf, using a micro syri [...] nge, and adding 10 µL of a solution with specific activity of 1,400 Bq, 45 days after plant emergence. The concentration of the glyphosate translocated in the plant was evaluated at time intervals of 6, 12, 36 and 72 hours after being applied on the application leaf, stem, roots and leaves. Ten hours after treatment application, the distribution of the product in the application leaf, divided into base, center and apex, was also evaluated by measuring the radiation emitted by 14C-glyphosate in a liquid scintillation spectrometer. Greater glyphosate retention was observed in the resistant biotype leaf, approximately 90% of the total absorbed up to 72 hours. In the susceptible biotype, this value was close to 70% in the same period. Susceptible biotype leaves, stem and roots showed greater concentration of glyphosate, indicating greater translocation efficiency in this biotype. In the resistant biotype, the herbicide accumulated in greater quantity at the apex and center of the application leaf, while in the susceptible biotype greater accumulation was observed at the base and center leaf. Thus, it can be stated that the resistance mechanism is related to the differential translocation of this herbicide in the biotypes.

  16. Resposta de biótipos de Euphorbia heterophylla a doses de glyphosate / Response of Euphorbia heterophylla biotypes to glyphosate rates

    Scientific Electronic Library Online (English)

    L, Vargas; M.A, Nohatto; D, Agostinetto; M.A, Bianchi; E.M, Gonçalves; R.E, Toledo.

    Full Text Available A leiteira (Euphorbia heterophylla) é uma planta daninha de ciclo anual encontrada com frequência em lavouras de soja na região Sul do Brasil, controlada em lavouras de soja geneticamente modificada (Roundup Ready® - RR) com uso do herbicida glyphosate. Entretanto, nos últimos anos, o controle dessa [...] espécie não tem sido satisfatório em alguns locais, provocando a suspeita de que foram selecionados biótipos resistentes ao herbicida. Diante disso, o objetivo deste trabalho foi avaliar, por meio de curvas de dose-resposta, biótipos de leiteira com suspeita de resistência ao glyphosate. O experimento foi realizado em casa de vegetação, em delineamento experimental completamente casualizado, com quatro repetições. Os tratamentos constituíram-se de doses crescentes de glyphosate (0, 90, 180, 360, 720, 1.080, 1.440 e 2.160 g e.a. ha-1), aplicadas sobre cinco biótipos de leiteira, oriundos de lavouras de soja RR do Estado do Rio Grande do Sul. As variáveis avaliadas foram controle e matéria seca da parte aérea. Os resultados evidenciam que os biótipos de leiteira avaliados são suscetíveis ao glyphosate. Abstract in english Wild poinsettia is an annual cycle weed, commonly found in soybean crop in southern Brazil. It is controlled by glyphosate in genetically- modified soybean (Roundup Ready® - RR). The control of this species has not proven to be satisfactory in some places in the last years, leading to the suspicion [...] that biotypes resistant to glyphosate have been selected. The objective this work was to evaluate, by response-dose curve, wild poinsettia biotypes with suspected resistance to glyphosate. The experiment was conducted under greenhouse conditions and the experiment was arranged in a randomized complete block design, with four replications. The treatments consisted of increased application rates of glyphosate (0, 90, 180, 360, 720, 1,080, 1,440 and 2,160 g a.e. ha-1) on five wild poinsettia biotypes, from crop soybean RR in the state of Rio Grande do Sul. Control and dry weight were evaluated. The results indicated that the wild poinsettia biotypes are susceptible to glyphosate.

  17. Deriva simulada do glyphosate em cultivares de café Acaiá e Catucaí / Simulated glyphosate drift on Acaiá and Catucaí coffee cultivars

    Scientific Electronic Library Online (English)

    A.C., França; F.P., Carvalho; C.M.T., Fialho; L., D' Antonino; A.A., Silva; J.B., Santos; L.R., Ferreira.

    2013-06-01

    Full Text Available O objetivo desta pesquisa foi avaliar os efeitos da deriva simulada de glyphosate sobre o crescimento inicial de dois cultivares de café de crescimento distinto. Utilizou-se o delineamento em blocos casualizados com quatro repetições, sendo os tratamentos distribuídos em esquema fatorial 2x5. No pri [...] meiro fator foram alocados os cultivares e, no segundo, as subdoses do glyphosate (0, 57,6; 115,2; 230,4; e 460,8 g ha-1). No dia da aplicação e também aos 45 e 120 dias após aplicação (DAA), avaliaram-se a altura, a área foliar, o diâmetro do caule, o número de ramos plagiotrópicos e de folhas; aos 10, 45 e 120 DAA foram avaliados os sintomas de intoxicação nas plantas e, aos 120 DAA, o acúmulo de massa seca de caule, folhas e raízes. Os sintomas de intoxicação nas plantas de café causados pelo glyphosate foram caracterizados por clorose e estreitamento do limbo foliar nos dois cultivares estudados. Todavia, sintomas mais severos foram verificados no cultivar Acaiá a partir de 10 DAA, como necrose de folhas mais novas da parte mediana da planta. Conclui-se que o cultivar Acaiá é menos tolerante ao glyphosate, quando comparado ao Catucaí, pois apresentou menor crescimento que o Catucaí quando submetidos ao tratamento com o herbicida, ou seja, pode ocorrer tolerância diferencial entre cultivares de crescimento distinto. Abstract in english This study aimed to evaluate the effects of simulated glyphosate drift on the growth of two cultivars with distinct growing patterns. The experiment was arranged in a randomized block design, with four repetitions, and the treatments were distributed in a factorial scheme 2x5, with two cultivars in [...] the first factor and the glyphosate subdoses (0, 57.6; 115.2; 230.4 and 460.8 g ha?1) in the second factor. On the day glyphosate was applied and at 45 and 120 days after application (DAA), height, leaf area, stem diameter, and number of plagiotropic branches and leaves were evaluated; at 10, 45 and 120 DAA, plant intoxication symptoms were visually evaluated and at 120 DAA, dry mass accumulation of the stem, leaves, and roots was evaluated. The intoxication symptoms of the coffee plants caused by glyphosate were characterized by chlorosis and leaf narrowing in the two cultivars studied. However, more severe symptoms were verified in the Acaiá cultivars from 10 DAA on, such as necrosis of younger leaves in the median part of the plant. It was concluded that Acaiá cultivar is less tolerant to glyphosate than Catucaí cultivar, since it showed lower growth when submitted to herbicide treatment, i.e., tolerance can vary between cultivars with distinct growing patterns.

  18. Buva (Conyza bonariensis) resistente ao glyphosate na região sul do Brasil Conyza bonariensis biotypes resistant to the glyphosate in southern Brazil

    OpenAIRE

    L. VARGAS; M.A Bianchi; M.A Rizzardi; D Agostinetto; T Dal magro

    2007-01-01

    O glyphosate é um herbicida não-seletivo utilizado para controlar plantas daninhas há mais de 20 anos no Rio Grande do Sul. A buva (Conyza bonariensis) é uma espécie daninha comum nos Estados da região Sul do Brasil e tradicionalmente controlada com uso de glyphosate. Entretanto, nos últimos anos plantas de buva têm apresentado poucos sintomas de toxicidade em resposta ao tratamento com glyphosate, sugerindo que estas plantas são resistentes ao herbicida. Assim, com o objetivo de avaliar a re...

  19. Micromorfologia foliar na análise da fitotoxidez por glyphosate em Eucalyptus grandis Leaf micromorphology in the analysis of glyphosate toxicity in Eucalyptus grandis

    OpenAIRE

    Tuffi Santos, L.D.; B.F Sant'anna-Santos; R.M.S.A. Meira; Ferreira, F.A.; R.A.S.T. Tiburcio; E.C.F. Silva

    2009-01-01

    Foram avaliados os efeitos da deriva de formulações comerciais de glyphosate sobre a superfície foliar e o crescimento de clones de eucalipto. Mudas de seis clones foram submetidas a 129,6 g ha-1 de glyphosate das formulações comerciais Scout®, Roundup NA®, Roundup transorb® e Zapp QI®. Entre os clones não foram identificadas diferenças quanto à tolerância ao glyphosate. Plantas expostas à deriva simulada de Roundup transorb® e Zapp QI® apresentaram, respectivamente, a maior e menor porcentag...

  20. Características da epiderme foliar de eucalipto e seu envolvimento com a tolerância ao glyphosate Characteristics of eucalypt leaf epidermis and its role in glyphosate tolerance

    OpenAIRE

    Tuffi Santos, L.D.; L. Iarema; M. Thadeo; Ferreira, F.A.; R.M.S.A. Meira

    2006-01-01

    Em áreas de reflorestamento, a deriva do glyphosate causa injúrias nas plantas de eucalipto. Trabalhos preliminares de pesquisa e observações de campo apontam para uma tolerância diferencial ao glyphosate entre os genótipos cultivados. Nesse contexto, objetivou-se estudar as estruturas anatômicas da epiderme foliar de cinco espécies de eucalipto, correlacionando com a tolerância ao glyphosate em deriva simulada. Utilizou-se o esquema fatorial, sendo cinco espécies (Eucalyptus urophylla, E. gr...

  1. Effects of glyphosate and endosulfan on soil microorganisms in soybean crop Efeitos do endosulfan e glyphosate sobre microrganismos do solo na cultura da soja

    OpenAIRE

    Pereira, J.L.; M.C. Picanço; Silva, A. A.; E.A Santos; H.V.V. Tomé; J.B. Olarte

    2008-01-01

    Transgenic soybean, resistant to glyphosate, is the most dominant transgenic crop grown commercially in the world. Research works on herbicide and insecticide mixtures and their effects on microorganisms are rarely reported. This work aimed to study the impact of glyphosate, endosulfan and their mixtures on the microbial soil activity in soybean crop. The experiment was carried out in a complete randomized block design with four treatments and five replications. The treatments were glyphosate...

  2. Mothers' depressive symptoms predict both increased and reduced negative reactivity: aversion sensitivity and the regulation of emotion.

    Science.gov (United States)

    Dix, Theodore; Moed, Anat; Anderson, Edward R

    2014-07-01

    This study examined whether, as mothers' depressive symptoms increase, their expressions of negative emotion to children increasingly reflect aversion sensitivity and motivation to minimize ongoing stress or discomfort. In multiple interactions over 2 years, negative affect expressed by 319 mothers and their children was observed across variations in mothers' depressive symptoms, the aversiveness of children's immediate behavior, and observed differences in children's general negative reactivity. As expected, depressive symptoms predicted reduced maternal negative reactivity when child behavior was low in aversiveness, particularly with children who were high in negative reactivity. Depressive symptoms predicted high negative reactivity and steep increases in negative reactivity as the aversiveness of child behavior increased, particularly when high and continued aversiveness from the child was expected (i.e., children were high in negative reactivity). The findings are consistent with the proposal that deficits in parenting competence as depressive symptoms increase reflect aversion sensitivity and motivation to avoid conflict and suppress children's aversive behavior. PMID:24796661

  3. Evaluation of glyphosate and paraquat in management of Brachiaria ruziziensis

    Directory of Open Access Journals (Sweden)

    Neumarcio Vilanova Costa

    2013-04-01

    Full Text Available The objective of this study was to evaluate the effect of doses of paraquat and glyphosate on desiccation Brachiaria ruziziensis. The experimental design was randomized blocks with four replications. The rates glyphosate were 0, 90, 180, 360, 720 and 1440 g ha-1 and paraquat were 0, 50, 100, 200, 400 and 800 g ha-1. Based on the results obtained it can be concluded that paraquat was ineffective in desiccation B. ruziziensis and the glyphosate was only effective at rates of 720 and 1440g ha-1. There was no issuance of new tillers after desiccation of forage plants to allow practical use for management in crop-livestock system.

  4. Acute eosinophilic pneumonia associated with glyphosate-surfactant exposure.

    Science.gov (United States)

    De Raadt, Wanda M; Wijnen, Petal A; Bast, Aalt; Bekers, Otto; Drent, Marjolein

    2015-01-01

    We report a case of a female patient who developed acute eosinophilic pneumonia (AEP) after recent onset of smoking and exposure to glyphosate-surfactant.The additional exposure associated with the recent start of smoking may have contributed to the development and/or severity of AEP.A clinical relapse after re-challenge four years later both with smoking and glyphosate-surfactant made the association highly likely.Respiratory distress is a factor of poor outcome and mortality after ingestion of glyphosate-surfactant.This case highlights the importance of a thorough exposure history e.g., possible occupational and environmental exposures together with drug-intake.Genotyping should be considered in cases of severe unexplained pulmonary damage. PMID:26278698

  5. Effects of glyphosate and endosulfan on soil microorganisms in soybean crop Efeitos do endosulfan e glyphosate sobre microrganismos do solo na cultura da soja

    Directory of Open Access Journals (Sweden)

    J.L. Pereira

    2008-01-01

    Full Text Available Transgenic soybean, resistant to glyphosate, is the most dominant transgenic crop grown commercially in the world. Research works on herbicide and insecticide mixtures and their effects on microorganisms are rarely reported. This work aimed to study the impact of glyphosate, endosulfan and their mixtures on the microbial soil activity in soybean crop. The experiment was carried out in a complete randomized block design with four treatments and five replications. The treatments were glyphosate 480 SL [540 g of active ingredient (a.i. ha-1], endosulfan 350 EC (525 g a.i. ha-1, the glyphosate 480 SL [540 g of active ingredient (a.i. ha-1] mixed with endosulfan 350 EC (525 g a.i. ha-1 and the control. Microbial activity was evaluated five days after treatment application. Glyphosate application was not an impacting factor for soil CO2 production. Endosulfan application (alone or mixed with glyphosate suppressed CO2 production by microorganisms in the soil. Microbial biomass and microbial quotient were lower in the treatments using endosulfan alone and in those using endosulfan mixed with glyphosate than in the treatments using glyphosate alone and control.A soja resistente ao glyphosate é a cultura transgênica mais cultivada em todo o mundo. Pesquisas envolvendo o impacto de mistura de herbicidas e inseticidas e seus efeitos sobre microrganismos do solo são raramente reportadas. Este trabalho teve por objetivo avaliar o impacto do herbicida (glyphosate, do inseticida (endosulfan e da mistura de ambos sobre a atividade microbiana do solo na cultura da soja. O delineamento experimental foi em blocos casualizados, com quatro tratamentos e cinco repetições. Os tratamentos foram o herbicida glyphosate 480 SL [540 g de ingrediente ativo (i.a. ha-1], endosulfan 350 EC (525 g i.a. ha-1, a mistura de glyphosate 480 SL (540 g de i.a. ha-1 com endosulfan 350 EC (525 g i.a. ha-1 e a testemunha onde se aplicou água. A atividade microbiana foi avaliada aos cinco dias após a aplicação dos tratamentos. A aplicação de glyphosate não afetou a produção de CO2 pela microbiota do solo. A aplicação de endosulfan (isolado ou em mistura com o glyphosate reduziu a produção de CO2 pelos microrganismos do solo. A biomassa microbiana e o quociente metabólico foram menores nos tratamentos submetidos à aplicação de endosulfan isolado e em mistura com glyphosate, em comparação àqueles submetidos à aplicaçao de glyphosate isolado e à testemunha.

  6. Real-time digital compensation to reduce acceleration's sensitivity in quartz resonator.

    Science.gov (United States)

    Qingxiao, Shan; Jun, Yang; Jianyun, Chen; Longzhe, Ji; Feijiang, Huang

    2012-06-01

    The paper presents a digital compensator imposing real-time voltage to compensate the frequency offset of quartz resonator under acceleration. To begin with, a triple-axis MEMS acceleration sensor, whose package is less than 3 mm × 3 mm × 0.9 mm, is mounted at the bottom of quartz resonator. Then acceleration sensitivity vector, based on sensor's coordinator, can be calculated by imposing sinusoidal vibration on singular axis and measuring the amplitude of sideband. So, the frequency offset can be calculated and the compensate value can also be inferred. A digital circuit is designed to generate compensate voltage real time to counteract the frequency offset. A FPGA is employed, which can realize computation in one clock period. Experiments show that the digital compensator presented here has a good effect at low frequency vibration just at which mechanical cushion is ineffective. At steady state, it can almost eliminate the frequency offset. Because of the integration and miniaturization of digital elements, the whole compensator is flexible, low cost, and easy to be applied. PMID:22755650

  7. Chemical control of different Digitaria insularis populations and management of a glyphosate-resistant population / Controle químico de diferentes populações de Digitaria insularis e manejo de uma população resistente ao glyphosate

    Scientific Electronic Library Online (English)

    N.M., CORREIA; L.T., ACRA; G., BALIEIRO.

    2015-03-01

    Full Text Available Objetivou-se neste trabalho estudar o controle de diferentes populações de Digitaria insularis pelo herbicida glyphosate, isolado e em mistura, além da combinação de métodos (químico e mecânico) no manejo de plantas adultas resistentes. Três experimentos foram desenvolvidos: um em vasos mantidos em [...] condição ambiente e dois em condição de campo. No experimento em vasos, 12 populações de D. insularis foram pulverizadas com glyphosate isolado (1,44 e 2,16 kg e.a. ha-1) e em mistura (1,44 e 2,16 kg e.a. ha-1) com quizalofop-p-tefuryl (0,12 kg i.a. ha-1). O tratamento de 1,44 kg e.a. ha-1 de glyphosate mais 0,12 kg i.a. ha-1 de quizalofop foi suficiente para o controle adequado (>95%) de todas as populações. A população 11 (área de produção de grãos em Itumbiara - GO) foi considerada sensível ao glyphosate, e as demais, medianamente sensíveis ou tolerantes ao herbicida. Em campo, as plantas de D. insularis de um dos experimentos foram roçadas e, no outro, não. Oito tratamentos com herbicidas [glyphosate isolado (1,44 e 2,16 kg e.a. ha-1) e em mistura (1,44 e 2,16 kg e.a. ha-1) com quizalofop-p-tefuryl a 0,12 kg i.a. ha-1, clethodim a 0,108 kg i.a. ha-1 ou nicosulfuron a 0,06 kg i.a. ha-1] foram avaliados, combinados com ou sem a aplicação sequencial de tratamento padrão, pulverizado 15 dias após a primeira a aplicação. A combinação do controle mecânico com a aplicação de glyphosate (2,16 e 1,44 kg e.a. ha-1) mais quizalofop-p-tefuryl (0,12 kg i.a. ha-1) ou clethodim (0,108 kg i.a. ha-1), associados à aplicação sequencial, foi a estratégia mais eficaz para o manejo de plantas adultas de D. insularis resistentes. Abstract in english This study aimed to control different populations of Digitaria insularis by glyphosate herbicide, isolated and mixed, besides the combination of methods (chemical and mechanical) to manage resistant adult plants. Three experiments were conducted, one in pots which were maintained under non-controlle [...] d conditions and two under field conditions. In the experiment in pots, twelve populations of D. insularis were sprayed with isolated glyphosate (1.44 and 2.16 kg a.e. ha-1) and mixed (1.44 and 2.16 kg a.e. ha-1) with quizalofop-p tefuryl (0.12 kg i.a. ha-1). The treatment of 1.44 kg a.e. ha-1 of glyphosate plus 0.12 kg a.i. ha-1 of quizalofop was sufficient for adequate control (>95%) of all populations. Population 11 (area of grain production in Itumbiara, GO) was considered sensitive to glyphosate. Others populations were moderately sensitive or tolerant to the herbicide. In the field, the plants of D. insularis of one of the experiments were mowed and, in the other, there were not. Eight treatments with herbicides [isolated glyphosate (1.44 and 2.16 kg a.e. ha-1) and mixed (1.44 and 2.16 kg a.e. ha-1) with quizalofop-p-tefuryl at 0.12 kg a.i. ha-1), clethodim at 0.108 kg a.i. ha-1) or nicosulfuron at 0.06 kg a.i. ha-1)] were assessed, in combination with or without sequential application of the standard treatment, sprayed 15 days after the first application. The combination of the mechanic control with the application of glyphosate (2.16 and 1.44 kg a.e. ha-1) plus quizalofop-p-tefuryl (0.12 kg a.i. ha-1) or clethodim (0.108 kg a.i. ha-1), associated to the sequential application, was the most effective strategy for the management of adult plants of resistant D. insularis.

  8. Glyphosate tolerant volunteer corn control at two development stages / Controle do milho voluntário tolerante ao glyphosate em dois estádios de desenvolvimento

    Scientific Electronic Library Online (English)

    N.V., Costa; L.H.S., Zobiole; C.A., Scariot; G.R., Pereira; G., Moratelli.

    2014-12-01

    Full Text Available Os grãos perdidos na colheita de culturas tolerantes ao glyphosate podem originar plantas voluntárias que apresentam restrições ao manejo de dessecação no sistema de plantio direto, bem como causar interferência na cultura sucessora transgênica ou convencional. Objetivou-se neste trabalho avaliar o [...] controle do milho voluntário tolerante ao glyphosate em dois estádios de desenvolvimento. Dois experimentos foram conduzidos: um para o controle no estádio V5 e outro para o controle no estádio V8 do milho hibrido triplo 2B688 HR (tolerante a lepidópteros e ao glyphosate). Utilizou-se o delineamento de blocos casualizados com quatro repetições. Os tratamentos avaliados foram: haloxyfop (25 g ha-1), haloxyfop (50 g ha-1), haloxyfop (62 g ha-1), haloxyfop + 2,4-D (25 + 670gha-1), haloxyfop + 2,4-D (50 + 670gha-1), haloxyfop + 2,4-D (62 + 670gha-1), haloxyfop + fluroxypyr (25 + 200gha-1), haloxyfop + fluroxypyr (50 + 200gha-1), haloxyfop + fluroxypyr (62 + 200gha-1), clethodim (84gha-1), clethodim + 2,4-D (84 + 670gha-1), clethodim + fluroxypyr (84 + 200 g ha-1) e uma testemunha sem aplicação. As aplicações no estádio V5 do haloxyfop e do clethodim isolados ou em mistura com 2,4-D e com fluroxypyr apresentaram controle máximo (100%) entre 32 e 39 dias após a aplicação, com exceção da mistura haloxyfop +2,4-D (25 + 670 g ha-1) que não promoveu controle satisfatório. Para o estádio V8, as misturas haloxyfop +2,4-D (50+670gha-1) e haloxyfop +2,4-D (62+670gha-1) demoraram até 6 e 10 dias a mais para atingirem controle satisfatório a excelente, quando comparados com as aplicações isoladas do haloxyfop nas mesmas doses, respectivamente. O clethodim aplicado isolado e em mistura com 2,4-D e com fluroxypyr não apresentou controle satisfatório. Concluiu-se que os herbicidas mostraram controle eficiente em aplicações no estádio V5 das plantas do milho voluntário transgênico, com exceção da mistura haloxyfop + 2,4-D (25 + 670gha-1). Para as aplicações no estádio V8, o haloxyfop isolado e em mistura com fluroxypyr foi o que demonstrou controle excelente em todas as doses avaliadas. A mistura com 2,4-D pode reduzir a eficiência do haloxyfop em baixas doses. O clethodim isolado e em mistura com o 2,4-D ou com fluroxypyr não foi eficiente. Abstract in english The loss of grains during the harvest of glyphosate tolerant corn may generate volunteer plants, which can interfere in the conventional or glyphosate crop in succession. The current work aim to evaluate the control of the volunteer corn glyphosate tolerant under two weed stages. Aimed to evaluate t [...] he control of volunteer glyphosate tolerant corn in two stages of development. There were conducted two experiments with hybrid 2B688 HR (lepidoptera and glyphosate tolerant), the application were at V5 and V8 stage. The experiment was randomized block design with four replicates, using the treatments: haloxyfop at 25, 50 and 62 g ha-1 alone and associated with 2,4-D at 670 g ha-1 or fluroxypyr at 200 g ha-1. The standard was clethodim at 84 g ha-1 with 2,4-D and fluroxypyr at same rates. The applications of haloxyfop and clethodim both isolated or in a mixture with 2,4-D and fluroxypyr at V5 stage showed total control (100%) at 32 and 39 days after the application, except for haloxyfop + 2,4-D (25 + 670 g ha-1) mixture, which did not provided adequate control. At V8 stage, haloxyfop + 2,4-D (50 + 670 g ha-1) and haloxyfop + 2,4-D (62 + 670 g ha-1) mixtures took up to 6 and 10 days or longer to reach adequate to excellent control, when compared to haloxyfop isolated applications in the same doses, respectively. Either isolated clethodim or mixed with 2, 4-D and fluroxypyr did not show adequate control. The treatments showed efficient control on volunteer corn plants at V5 stage, except for haloxyfop + 2, 4-D (25 + 670 g ha-1) mixture. At V8 stage applications, haloxyfop either isolated or mixture with fluroxypyr demonstrated excellent control on every evaluated dose. The mixture with 2, 4-D can reduce haloxyfop effic

  9. Potential for drifting of mix 2,4-D + glyphosate

    Directory of Open Access Journals (Sweden)

    Marco Antonio Gandolfo

    2012-12-01

    Full Text Available The application of the mixture of glyphosate with 2,4-d took on great importance with high adoption of no-tillage system in the early 90s, and with the constant reports of weed biotypes resistant to glyphosate. However, studies on the drift of this mixture are still scarce. The aim of this study was to evaluate the potential drift of these herbicides, with or without the adjuvant, applied in wind tunnel. The experimental design was completely randomized considered, arranged in a factorial design 5 x 3, with four replications, and five tails and three collection distances (5, 10 and 15 meters. The spray tested were: glyphosate, 2,4-D, 2,4-D+glyphosate, glyphosate+2,4-D+adjuvant, and a control in which water was applied. The collection points were installed at 5, 10 and 15 meters and in this points each 20 cm of height in relation of tunnel ground until 1,0 m of height. The application of the products took place in a wind tunnel with 20 m length and cross-sectional 4 m2 with speed wind of 2.0 m s-1,. The mean values obtained in the samples were subjected to analysis of variance, and their means were compared by Tukey test at 5% probability. It was observed that herbicide application associated produces more drift than when applied alone mainly to 5 and 10 meters of distance to sprayer boom. The drift of each herbicide applied alone did not differ. When added to the adjuvant mixture glyphosate plus 2,4-D, there was a 23% reduction in drift at 5 m and 6 m to 10%.

  10. Palmitoleic acid reduces intramuscular lipid and restores insulin sensitivity in obese sheep

    Directory of Open Access Journals (Sweden)

    Duckett SK

    2014-11-01

    Full Text Available Susan K Duckett, Gabriela Volpi-Lagreca, Mariano Alende, Nathan M LongAnimal and Veterinary Sciences Department, Clemson University, Clemson, SC, USAAbstract: Obese sheep were used to assess the effects of palmitoleic (C16:1 cis-9 acid infusion on lipogenesis and circulating insulin levels. Infusion of 10 mg/kg body weight (BW/day C16:1 intravenously in obese sheep reduced (P<0.01 weight gain by 77%. Serum palmitoleic levels increased (P<0.05 in a linear manner with increasing levels of C16:1 infusion. Cis-11 vaccenic (C18:1 cis-11 acid, a known elongation product of palmitoleic acid, was also elevated (P<0.05 in serum after 14 days and 21 days of infusion. Plasma insulin levels were lower (P<0.05 (10 mg/kg BW/day C16:1 than controls (0 mg/kg BW/day C16:1 at 14 days and 28 days of infusion. Infusion of C16:1 resulted in linear increases in tissue concentrations of palmitoleic, cis-11 vaccenic, eicosapentaenoic, and docosapentaenoic acids in a dose-dependent manner. Total lipid content of the semitendinosus (ST muscle and mesenteric adipose tissue was reduced (P<0.01 in both 5 mg/kg and 10 mg/kg BW C16:1 dose levels. Total lipid content and mean adipocyte size in the longissimus muscle was reduced (P<0.05 in the 10 mg/kg BW C16:1 dose level only, whereas total lipid content and adipocyte size of the subcutaneous adipose tissue was not altered. Total lipid content of the liver was also unchanged with C16:1 infusion. Palmitoleic acid infusion upregulated (P<0.05 acetyl-CoA carboxylase (ACC, fatty acid elongase-6 (ELOVL6, and Protein kinase, AMP-activated, alpha 1 catalytic subunit, transcript variant 1 (AMPK mRNA expressions in liver, subcutaneous adipose, and ST muscle compared to the controls. However, mRNA expression of glucose transporter type 4 (GLUT4 and carnitine palmitoyltransferase 1b (CPT1B differed between tissues. In the subcutaneous adipose and liver, C16:1 infusion upregulated (P<0.05 GLUT4 and CPT1B, whereas these genes were downregulated (P<0.05 in ST muscle with C16:1 infusion. These results show that C16:1 infusion for 28 days reduced weight gain, intramuscular adipocyte size and total lipid content, and circulating insulin levels. These changes appear to be mediated through alterations in expression of genes regulating glucose uptake and fatty acid oxidation specifically in the muscles.Keywords: adipocytes, longissimus muscle, lipogenesis, insulin level, serum, fatty acid

  11. The free energy cost of reducing noise while maintaining a high sensitivity

    CERN Document Server

    Sartori, Pablo

    2015-01-01

    Living systems need to be highly responsive, and also to keep fluctuations low. These goals are incompatible in equilibrium systems due to the Fluctuation Dissipation Theorem (FDT). Here, we show that biological sensory systems, driven far from equilibrium by free energy consumption, can reduce their intrinsic fluctuations while maintaining high responsiveness. By developing a continuum theory of the E. coli chemotaxis pathway, we demonstrate that adaptation can be understood as a non-equilibrium phase transition controlled by free energy dissipation, and it is characterized by a breaking of the FDT. We show that the maximum response at short time is enhanced by free energy dissipation. At the same time, the low frequency fluctuations and the adaptation error decrease with the free energy dissipation algebraically and exponentially, respectively.

  12. Free Energy Cost of Reducing Noise while Maintaining a High Sensitivity

    Science.gov (United States)

    Sartori, Pablo; Tu, Yuhai

    2015-09-01

    Living systems need to be highly responsive, and also to keep fluctuations low. These goals are incompatible in equilibrium systems due to the fluctuation dissipation theorem (FDT). Here, we show that biological sensory systems, driven far from equilibrium by free energy consumption, can reduce their intrinsic fluctuations while maintaining high responsiveness. By developing a continuum theory of the E. coli chemotaxis pathway, we demonstrate that adaptation can be understood as a nonequilibrium phase transition controlled by free energy dissipation, and it is characterized by a breaking of the FDT. We show that the maximum response at short time is enhanced by free energy dissipation. At the same time, the low frequency fluctuations and the adaptation error decrease with the free energy dissipation algebraically and exponentially, respectively.

  13. Tracing the origin and mobilization of Glyphosate and AMPA in a vineyard catchment

    Science.gov (United States)

    Gassmann, Matthias; Olsson, Oliver; Payraudeau, Sylvain; Imfeld, Gwenaël; Kümmerer, Klaus

    2014-05-01

    Pesticides residues are often found in storm-water runoff in agricultural areas. There are several pathways along which pesticides may be transported from their application point towards the river. Although the primary target of pesticide application is the agricultural area, wind drift transports pesticide droplets to non-target areas. Furthermore, miss-operation of application machines results in the deposition of pesticides at filter strips or roads from where they can be washed off. Therefore, it may be difficult to identify the origin of pesticides in storm-water runoff. However, management of water quality requires that critical source areas are clearly delineated in order to effectively reduce water pollution. In the Rouffach catchment, a 42.7 ha vineyard catchment in France, Glyphosate and its transformation product AMPA occurred frequently and in high concentrations in runoff water during rainfall-runoff events in 2008. In order to identify the source areas of Glyphosate residue pollution and its mobilization, we used here a combination of sampling data analysis techniques and distributed pollutant transfer modelling. Available sampling data allowed for an analysis by Normalized Cumulative Loads (NCL) at a high temporal resolution (10 min). The results imply that pollutant mobilization took place mainly at the beginning of an event. This First Flush suggests a wash off of substances from impervious surfaces such as roads. This assumption was confirmed by local hydrological knowledge about infiltration rates in the vineyard, which were not exceeded by rainfall intensities in most considered events. Additionally, the distributed process-based reactive transport model ZIN-AgriTra was used as a learning tool to evaluate the pesticide mobilization and export processes. The hydrological model was successfully calibrated and validated for long high-resolution time series of discharge data. Pesticide export modelling focused on the first rainfall-runoff event following the first significant Glyphosate application in 2008. Assuming only target Glyphosate application, hardly any export of Ghyphosate and AMPA occurred. Therefore, non-target application at adjacent roads was introduced into the model. By assuming different mobilization processes of substances on the roads, our results show that storage of sorbed pesticides (e.g. road sides, unpaved roads) and storage without sorption (e.g. plant surface, paved roads) significantly contributed to the total pesticide residue export. Concluding, it is likely that the major part of pesticides in runoff of the Rouffach catchment originates from the roads rather than from the vine growing areas and that the mobilization process is a combination of both sorptive and non-sorptive substance storage. Thus, avoiding non-target pesticide application could largely help to mitigate water contamination in this catchment.

  14. Reduced Sensitivity to Variation in Normality and Attractiveness for Other-Race Faces.

    Science.gov (United States)

    Mondloch, Catherine; Zhou, Xiaomei

    2015-09-01

    Adults recognize young faces and own-race faces more accurately than older and other-race faces, respectively. We recently reported that young and older adults are more sensitive to deviations from normality in young than older adult faces and that there is more between-participant variability (i.e., less consensus) in attractiveness ratings for older than young faces, suggesting that superior recognition of young adult faces is attributable to the dimensions of face space being optimized for young adult faces, presumably as the result of experience (Short & Mondloch, 2013; Short et al., 2014). In the current studies, we extended these findings to own- and other-race faces. In Experiment 1, Chinese and Caucasian adults (n= 24 per group) were shown own- and other-race face pairs in which one member of each pair was undistorted and the other had compressed or expanded features. They were asked to indicate which member of each face pair was more normal (a task that requires referencing a norm) and which was more expanded (a task that simply requires discrimination). Both Chinese and Caucasian participants were more accurate in judging the normality of own- than other-race faces, p face race in the discrimination task, p = .60. In Experiment 2, Chinese and Caucasian adults rated the attractiveness of 40 own-race and 40 other-race faces. Consensus among Chinese adults (n = 40) did not vary as a function of face race, p = .526; testing of Caucasians is ongoing. Collectively, these results provide direct evidence that perceptual experience with own-race faces optimizes the dimensions of faces space for own-race faces. Meeting abstract presented at VSS 2015. PMID:26326389

  15. High Sensitive Sensor Fabricated by Reduced Graphene Oxide/Polyvinyl Butyral Nanofibers for Detecting Cu (II) in Water.

    Science.gov (United States)

    Ding, Rui; Luo, Zhimin; Ma, Xiuling; Fan, Xiaoping; Xue, Liqun; Lin, Xiuzhu; Chen, Sheng

    2015-01-01

    Graphene oxide (GO)/polyvinyl butyral (PVB) nanofibers were prepared by a simple electrospinning technique with PVB as matrix and GO as a functional nanomaterial. GO/PVB nanofibers on glassy carbon electrode (GCE) were reduced through electrochemical method to form reduced graphene oxide (RGO)/PVB nanofibers. The morphology and structure of GO/PVB nanofiber were studied by scanning election microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR). RGO/PVB modified GCE was used for fabricating an electrochemical sensor for detecting Cu (II) in water. The analysis results showed that RGO/PVB modified GCE had good analytical results with the linear range of 0.06-2.2??M, detection limit of 4.10?nM (S/N = 3), and the sensitivity of 103.51??A·?M(-1)·cm(-2). PMID:25694783

  16. Cigarette smoke exposure severely reduces peripheral insulin sensitivity without changing GLUT4 expression in oxidative muscle of Wistar rats

    Directory of Open Access Journals (Sweden)

    Patricia Ebersbach-Silva

    2013-02-01

    Full Text Available OBJECTIVE: To evaluate the effect of exposure to cigarette smoke and running training on a treadmill on the expression of glucose transporter GLUT4 in oxidative soleus muscle of rats. MATERIALS AND METHODS: Wistar rats were divided into: (C control, (E exercise control, (SS, sedentary smoker, and (ES exercise smoker. Insulin Tolerance Test, Western blotting, and RT-PCR were performed for the evaluation of GLUT4 levels. RESULTS: The SS group presented lower insulin sensitivity with reduced GLUT4 protein in the plasma membrane (PM, no changes in the microsomal fraction, but increased mRNA content. Training reversed this condition. No intervention altered total GLUT4 content of the oxidative muscle. CONCLUSION: These results suggest that passive smoking stimulates GLUT4 transcription without changing total protein content, but impairs the ability of GLUT4 translocation to the PM. On the other hand, training seems to reduce the deleterious effects, even under the influence of cigarette smoking.

  17. Resistencia a herbicidas: Glifosato / Resistance to Herbicides: Glyphosate

    Scientific Electronic Library Online (English)

    Andrea, Villalba.

    2009-11-01

    Full Text Available Se presenta una revisión actualizada de los mecanismos generadores de resistencia a herbicidas, en plantas, y los factores que favorecen su desarrollo. Se reúnen las especies que actualmente han sido denunciadas como resistentes a glifosato, en Argentina y el mundo. Se explica el mecanismo de acción [...] y de desarrollo de resistencia de este xenobiótico, poniendo énfasis en las conductas preventivas. Abstract in english This paper presents a revision of resistance to herbicides mechanisms and factors of those developments in plants. Glyphosate resistent plants in Argentina and the world are considered. Mechanisms of action and development of glyphosate resistance and preventive behaviors are proposed. [...

  18. Influência da chuva na eficácia do glyphosate em mistura com adjuvantes na dessecação de plantas daninhas / Influence of rain on the efficacy of glyphosate in mixture with adjuvants in weed desiccation

    Scientific Electronic Library Online (English)

    A.F.F, Pedrinho Junior; F.M., Piva; G., Martini; G.V., Felici; J.C., Durigan.

    2002-08-01

    Full Text Available Com o objetivo de estudar a influência do momento da chuva após a aplicação do herbicida glyphosate isolado e em mistura com adjuvantes na dessecação de plantas daninhas, foram instalados dois experimentos na Fazenda Experimental de Ensino e Pesquisa da Faculdade de Ciências Agrárias e Veterinárias, [...] UNESP - campus de Jaboticabal-SP, em duas épocas: inverno de 2000 (junho - agosto) e verão de 2001 (janeiro-março). Os experimentos foram instalados no delineamento experimental de blocos ao acaso, em arranjo fatorial 4 (tratamentos herbicidas) x 5 (períodos livres de chuva simulada) + 1, com quatro repetições. Os tratamentos consistiram da combinação de glyphosate SAqC (360 g e.a. ha-1) isolado ou adicionado de uréia (50 g L-1 de calda) ou óleo vegetal (100 ml L-1 de calda) ou sulfato de amônio (100 g L-1 de calda), com cinco períodos de chuva simulada (1, 2, 4, 6 e > 48 horas após a aplicação), além de uma testemunha. A chuva foi simulada com um sistema de irrigação por aspersão, e a quantidade aplicada variou entre 18 e 19 mm. Em ambas as épocas a chuva foi prejudicial à ação do glyphosate, principalmente nos menores períodos livres de chuva após a aplicação. Os sintomas de fitointoxicação apareceram mais rapidamente no verão. A utilização de adjuvantes na calda de pulverização não beneficiou o desempenho do herbicida glyphosate no controle das plantas daninhas, no inverno. A adição de uréia (50 g L¹) é uma boa alternativa para o controle de plantas daninhas, no verão, em situações sujeitas à chuva até duas horas após a aplicação. Abstract in english The objective of this research was to evaluate the effects of the moment of rain on the activity of the herbicide glyphosate, applied alone and in combination with surfactants, on two growing seasons (winter and summer); at FCAV-UNESP Experimental Station, Jaboticabal-SP, Brazil,, during 2000/2001. [...] The winter experiment was installed from June to August 2000 and the summer one from January to March 2001. The treatments were glyphosate SAqC (360 g e.a. ha-1), alone or in combination with urea (50 g L-1), vegetable oil (100 ml L-1) or ammonium sulfate (100 g L-1), and five periods of simulated rainfall (1, 2, 4, 6 or 48 hours after application) and a check treatment. The experimental design was set up in a randomized block factorial, 5 (herbicides) x 6 (moment of rain) + 1 (controls treatment), with four replications. The artificial rain was provided by a top irrigation system supplying 18-19 mm rain during one hour. The artificial rain reduced the glyphosate action, mainly in the earlier periods. The herbicide symptoms appeared sooner in the summer trial. The use of surfactants in the spray mixture did not improve the performance of glyphosate on weed control during the winter. The addition of urea (50 g L-1), is a good alternative for weed control during summer, when rainfall is expected after the application.

  19. Influência da chuva na eficácia do glyphosate em mistura com adjuvantes na dessecação de plantas daninhas Influence of rain on the efficacy of glyphosate in mixture with adjuvants in weed desiccation

    Directory of Open Access Journals (Sweden)

    A.F.F Pedrinho Junior

    2002-08-01

    Full Text Available Com o objetivo de estudar a influência do momento da chuva após a aplicação do herbicida glyphosate isolado e em mistura com adjuvantes na dessecação de plantas daninhas, foram instalados dois experimentos na Fazenda Experimental de Ensino e Pesquisa da Faculdade de Ciências Agrárias e Veterinárias, UNESP - campus de Jaboticabal-SP, em duas épocas: inverno de 2000 (junho - agosto e verão de 2001 (janeiro-março. Os experimentos foram instalados no delineamento experimental de blocos ao acaso, em arranjo fatorial 4 (tratamentos herbicidas x 5 (períodos livres de chuva simulada + 1, com quatro repetições. Os tratamentos consistiram da combinação de glyphosate SAqC (360 g e.a. ha-1 isolado ou adicionado de uréia (50 g L-1 de calda ou óleo vegetal (100 ml L-1 de calda ou sulfato de amônio (100 g L-1 de calda, com cinco períodos de chuva simulada (1, 2, 4, 6 e > 48 horas após a aplicação, além de uma testemunha. A chuva foi simulada com um sistema de irrigação por aspersão, e a quantidade aplicada variou entre 18 e 19 mm. Em ambas as épocas a chuva foi prejudicial à ação do glyphosate, principalmente nos menores períodos livres de chuva após a aplicação. Os sintomas de fitointoxicação apareceram mais rapidamente no verão. A utilização de adjuvantes na calda de pulverização não beneficiou o desempenho do herbicida glyphosate no controle das plantas daninhas, no inverno. A adição de uréia (50 g L¹ é uma boa alternativa para o controle de plantas daninhas, no verão, em situações sujeitas à chuva até duas horas após a aplicação.The objective of this research was to evaluate the effects of the moment of rain on the activity of the herbicide glyphosate, applied alone and in combination with surfactants, on two growing seasons (winter and summer; at FCAV-UNESP Experimental Station, Jaboticabal-SP, Brazil,, during 2000/2001. The winter experiment was installed from June to August 2000 and the summer one from January to March 2001. The treatments were glyphosate SAqC (360 g e.a. ha-1, alone or in combination with urea (50 g L-1, vegetable oil (100 ml L-1 or ammonium sulfate (100 g L-1, and five periods of simulated rainfall (1, 2, 4, 6 or 48 hours after application and a check treatment. The experimental design was set up in a randomized block factorial, 5 (herbicides x 6 (moment of rain + 1 (controls treatment, with four replications. The artificial rain was provided by a top irrigation system supplying 18-19 mm rain during one hour. The artificial rain reduced the glyphosate action, mainly in the earlier periods. The herbicide symptoms appeared sooner in the summer trial. The use of surfactants in the spray mixture did not improve the performance of glyphosate on weed control during the winter. The addition of urea (50 g L-1, is a good alternative for weed control during summer, when rainfall is expected after the application.

  20. Photodegradation of glyphosate in the ferrioxalate system

    Energy Technology Data Exchange (ETDEWEB)

    Chen Yong [School of Resources and Environmental Science, Wuhan University, Wuhan 430079 (China); Wu Feng [School of Resources and Environmental Science, Wuhan University, Wuhan 430079 (China)], E-mail: fengwu@whu.edu.cn; Lin Yixin; Deng Nansheng [School of Resources and Environmental Science, Wuhan University, Wuhan 430079 (China); Bazhin, Nikolai; Glebov, Evgeni [Institute of Chemical Kinetics and Combustion, 3 Institutskaya St., Novosibirsk 630090 (Russian Federation)

    2007-09-05

    The photoinduced degradation of glyphosate (GLP) in the ferrioxalate system was investigated under irradiation with a 250 W metal halide lamp ({lambda} {>=} 365 nm). The efficiency of orthophosphates release, representing the photodegradation efficiency of GLP, increased with decreasing the initial concentrations of GLP and Fe(III)/oxalate ratios. At acidic pH value in the range of 3.5-5.0, higher efficiency of orthophosphates release up to 60.6% was achieved, while the efficiency dropped to 42.1% at pH 6.0. The photochemical process mainly involved the predominant species of iron(III), namely Fe(C{sub 2}O{sub 4}){sub 2}{sup -} and Fe(C{sub 2}O{sub 4}){sub 3}{sup 3-}, which lead to the formation of hydroxyl radicals in the presence of dissolved oxygen under UV-vis irradiation. Also, the complexation of GLP with Fe(III) obviously increased the light absorption of GLP and facilitated its degradation by direct photolysis. The ninhydrin test for primary amines showed that the GLP was attacked by hydroxyl radicals with C-N cleavage to yield aminomethylphosphonic acid (AMPA) and C-P cleavage to yield sarcosine. The photodegradation may be enhanced by the decomposition of reactive radicals produced through ligand-to-metal charge transfer (LMCT) of ferric-GLP complexes.

  1. Photodegradation of glyphosate in the ferrioxalate system

    International Nuclear Information System (INIS)

    The photoinduced degradation of glyphosate (GLP) in the ferrioxalate system was investigated under irradiation with a 250 W metal halide lamp (? ? 365 nm). The efficiency of orthophosphates release, representing the photodegradation efficiency of GLP, increased with decreasing the initial concentrations of GLP and Fe(III)/oxalate ratios. At acidic pH value in the range of 3.5-5.0, higher efficiency of orthophosphates release up to 60.6% was achieved, while the efficiency dropped to 42.1% at pH 6.0. The photochemical process mainly involved the predominant species of iron(III), namely Fe(C2O4)2- and Fe(C2O4)33-, which lead to the formation of hydroxyl radicals in the presence of dissolved oxygen under UV-vis irradiation. Also, the complexation of GLP with Fe(III) obviously increased the light absorption of GLP and facilitated its degradation by direct photolysis. The ninhydrin test for primary amines showed that the GLP was attacked by hydroxyl radicals with C-N cleavage to yield aminomethylphosphonic acid (AMPA) and C-P cleavage to yield sarcosine. The photodegradation may be enhanced by the decomposition of reactive radicals produced through ligand-to-metal charge transfer (LMCT) of ferric-GLP complexes

  2. Increasing the sensitivity of the visual system reduces kinetotic behaviour of fish under microgravity

    Science.gov (United States)

    Anken, Ralf; Hilbig, Reinhard; Knie, Miriam; Weigele, Jochen; Anken, Ralf

    We have shown earlier that some fish of a given batch reveal motion sickness (a kinetosis) at the transition from earth gravity to diminished gravity. The percentual ratios of the various types of behaviour (normal swimming and kinetotic swimming; kinetotic specimens revealed looping responses or spinning movements) highly differed depending on the quality of diminished gravity. At high quality microgravity (HQM, 10-6 g, ZARM drop-tower, Bremen, Germany), kinetoses were exhibited by some 90% of the animals, whereas kinetoses were not as frequently seen at higher G-levels (at 0.03-0.05g during parabolic aircraft flights or during centrifugation in the drop-capsule, only some 15-25% of the animals show kinetoses). In the course of the present study, we further assessed the role of the visual system in maintaining postural control under HQM, when the remaining level of gravity is too low to be used as a vestibular cue. Therefore, larval cichlid fish siblings (Oreochromis mossambicus) were subjected to drop-tower flights at HQM and different kinds of illumination were used. Applying blue light (which leads to an increase of the sensitivity of the visual system and to a general arousal of the animal) resulted in a decrease of kinetotically swimming specimens as compared to white and red light (red light is almost invisible for fish). The final data as well as results from analyses of inner ear otoliths will be communicated at the meeting. We expect that the few fish, which swam normally under white or red light, will have a very low otolith asymmetry (differences in the size of the right versus the left otoliths). Asymmetry may be considerably higher in animals swimming normally under blue light, since these specimens are presumed to rely entirely on visual input; an otolith asymmetry will thus not lead to a computation of erroneous vestibular cues. Acknowledgement: This work was financially supported by the German Aerospace Center (DLR) (FKZ: 50 WB 0527). The excellent technical assistance of Sandra Schroer is highly appreciated.

  3. Enhanced NH3-Sensitivity of Reduced Graphene Oxide Modified by Tetra-?-Iso-Pentyloxymetallophthalocyanine Derivatives.

    Science.gov (United States)

    Li, Xiaocheng; Wang, Bin; Wang, Xiaolin; Zhou, Xiaoqing; Chen, Zhimin; He, Chunying; Yu, Zheying; Wu, Yiqun

    2015-12-01

    Three kinds of novel hybrid materials were prepared by noncovalent functionalized reduced graphene oxide (rGO) with tetra-?-iso-pentyloxyphthalocyanine copper (CuPc), tetra-?-iso-pentyloxyphthalocyanine nickel (NiPc) and tetra-?-iso-pentyloxyphthalocyanine lead (PbPc) and characterized by Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), Raman spectra, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and atomic force microscope (AFM). The as-synthesized MPc/rGO hybrids show excellent NH3 gas-sensing performance with high response value and fast recovery time compared with bare rGO. The enhancement of the sensing response is mainly attributed to the synergism of gas adsorption of MPc to NH3 gas and conducting network of rGO with greater electron transfer efficiency. Strategies for combining the good properties of rGO and MPc derivatives will open new opportunities for preparing and designing highly efficient rGO chemiresistive gas-sensing hybrid materials for potential applications in gas sensor field. PMID:26403926

  4. Seletividade de glyphosate isolado ou em misturas para soja RR em aplicações sequenciais / Selectivity of glyphosate alone or in mixtures for RR soybean in sequential applications

    Scientific Electronic Library Online (English)

    D.G, Alonso; J, Constantin; R.S, Oliveira Jr; G, Santos; H.A, Dan; A.M, Oliveira Neto.

    2013-03-01

    Full Text Available O uso de misturas de herbicidas latifolicidas com o glyphosate tem sido uma alternativa para o controle de plantas daninhas resistentes ao glyphosate ou de difícil controle nos cultivos de soja RR. Este trabalho teve o objetivo de avaliar a seletividade de aplicações sequenciais de glyphosate, isola [...] do ou em mistura com latifolicidas, para a soja RR. As aplicações dos tratamentos foram feitas em plantas de soja cultivar CD214 RR nos estádios de desenvolvimento V1 a V2 e V3 a V4. Os herbicidas e as respectivas doses (g i.a. ha-1) utilizadas foram: glyphosate (g e.a. ha-1) isolado (720/480, 720/720, 960/960 e 1.200/1.200) e as misturas de glyphosate + cloransulam-methyl (720 + 15,12/480 + 15,12), glyphosate + fomesafen (720 + 62,5/480 + 62,5), glyphosate + lactofen (720 + 36/480 + 36), glyphosate + chlorimuron-ethyl (720 + 6,25/480 + 6,25), glyphosate + flumiclorac-pentyl (720 + 15/480 + 15), glyphosate + bentazon (720 + 240/480 + 240) e glyphosate + imazethapyr (720 + 40/480 + 40). O delineamento adotado foi o de blocos casualizados, em esquema de parcelas subdivididas, com quatro repetições. As variáveis avaliadas foram: fitointoxicação, altura de plantas, estande, fechamento do dossel, número de vagens por planta, massa de cem grãos e produtividade. Todos os tratamentos promoveram efeitos visuais de fitointoxicação na cultura da soja; todavia, em nenhuma das situações estudadas houve prejuízo no rendimento de grãos. Abstract in english The use of latifolicide mixed with glyphosate has been an alternative to control weeds resistant to glyphosate or difficult to control in RR soybean crops. The aim of this work was to evaluate the selectivity of sequential applications of glyphosate isolated or in mixture with latifolicide herbicide [...] s for RR soybean. Treatment applications were carried out on the soybean cultivar plants CD 214 RR at the developmental stages V1 up to V2 and V3 up to V4. The herbicides and respective rates (g a.i. ha-1) evaluated were: glyphosate (g a.e. ha¹) alone (720/480, 720/720, 960/960, and 1.200/1.200) and the mixtures glyphosate + cloransulam-methyl (720+15.12/480+15.12), glyphosate + fomesafen (720 + 62.5/480 + 62.5), glyphosate + lactofen (720 + 36/480 + 36), glyphosate + chlorimuron-ethyl (720 + 6.25/480 + 6.25), glyphosate + flumiclorac-pentyl (720 + 15/480 + 15), glyphosate + bentazon (720 + 240/480 + 240), and glyphosate + imazethapyr (720 + 40/480 + 40). The experimental design was completely randomized in a split-plot scheme with two checks, and four replicates. The variables analyzed were plant intoxication, plant height, stand,crop canopy, number of pods per plant, 100-grain mass, and yield. All the treatments promoted visual effects of plant intoxication on the soybean crop. However, yield loss was not observed in any of the situations studied.

  5. Seletividade de glyphosate isolado ou em misturas para soja RR em aplicações sequenciais Selectivity of glyphosate alone or in mixtures for RR soybean in sequential applications

    Directory of Open Access Journals (Sweden)

    D.G Alonso

    2013-03-01

    Full Text Available O uso de misturas de herbicidas latifolicidas com o glyphosate tem sido uma alternativa para o controle de plantas daninhas resistentes ao glyphosate ou de difícil controle nos cultivos de soja RR. Este trabalho teve o objetivo de avaliar a seletividade de aplicações sequenciais de glyphosate, isolado ou em mistura com latifolicidas, para a soja RR. As aplicações dos tratamentos foram feitas em plantas de soja cultivar CD214 RR nos estádios de desenvolvimento V1 a V2 e V3 a V4. Os herbicidas e as respectivas doses (g i.a. ha-1 utilizadas foram: glyphosate (g e.a. ha-1 isolado (720/480, 720/720, 960/960 e 1.200/1.200 e as misturas de glyphosate + cloransulam-methyl (720 + 15,12/480 + 15,12, glyphosate + fomesafen (720 + 62,5/480 + 62,5, glyphosate + lactofen (720 + 36/480 + 36, glyphosate + chlorimuron-ethyl (720 + 6,25/480 + 6,25, glyphosate + flumiclorac-pentyl (720 + 15/480 + 15, glyphosate + bentazon (720 + 240/480 + 240 e glyphosate + imazethapyr (720 + 40/480 + 40. O delineamento adotado foi o de blocos casualizados, em esquema de parcelas subdivididas, com quatro repetições. As variáveis avaliadas foram: fitointoxicação, altura de plantas, estande, fechamento do dossel, número de vagens por planta, massa de cem grãos e produtividade. Todos os tratamentos promoveram efeitos visuais de fitointoxicação na cultura da soja; todavia, em nenhuma das situações estudadas houve prejuízo no rendimento de grãos.The use of latifolicide mixed with glyphosate has been an alternative to control weeds resistant to glyphosate or difficult to control in RR soybean crops. The aim of this work was to evaluate the selectivity of sequential applications of glyphosate isolated or in mixture with latifolicide herbicides for RR soybean. Treatment applications were carried out on the soybean cultivar plants CD 214 RR at the developmental stages V1 up to V2 and V3 up to V4. The herbicides and respective rates (g a.i. ha-1 evaluated were: glyphosate (g a.e. ha¹ alone (720/480, 720/720, 960/960, and 1.200/1.200 and the mixtures glyphosate + cloransulam-methyl (720+15.12/480+15.12, glyphosate + fomesafen (720 + 62.5/480 + 62.5, glyphosate + lactofen (720 + 36/480 + 36, glyphosate + chlorimuron-ethyl (720 + 6.25/480 + 6.25, glyphosate + flumiclorac-pentyl (720 + 15/480 + 15, glyphosate + bentazon (720 + 240/480 + 240, and glyphosate + imazethapyr (720 + 40/480 + 40. The experimental design was completely randomized in a split-plot scheme with two checks, and four replicates. The variables analyzed were plant intoxication, plant height, stand,crop canopy, number of pods per plant, 100-grain mass, and yield. All the treatments promoted visual effects of plant intoxication on the soybean crop. However, yield loss was not observed in any of the situations studied.

  6. Translocação dos herbicidas glyphosate e imazamox em plantas de aguapé / Glyphosate and imazamox translocation in water hyacinth plants

    Scientific Electronic Library Online (English)

    C.F. de, Campos; H.S., Vitorino; G.S.F. de, Souza; D.C. de, Santana; D., Martins.

    2013-06-01

    Full Text Available Entre as diversas plantas daninhas encontradas em ambientes aquáticos, a Eichhornia crassipes é uma das principais, sendo espécie indesejável para muitas atividades. O objetivo deste trabalho foi avaliar a translocação de glyphosate e imazamox em plantas de E. crassipes. Foram estudados oito interva [...] los de tempo para o corte das folhas que receberam os herbicidas: 2, 4, 6, 8, 12 e 24 horas após a aplicação (HAA) dos produtos, além de um tratamento sem corte das plantas (testemunha). Utilizaram-se glyphosate na dose de 2.160 g e.a. ha-1 (produto comercial - Rodeo) + 0,5% v v-1 do espalhante adesivo aterbane e imazamox na dose de 290,4 g i.a. ha-1 (produto comercial - Clearcast). Os tratamentos foram instalados em um delineamento experimental inteiramente casualizado com quatro repetições. O glyphosate apresentou um controle insatisfatório quando realizado os cortes das folhas em todos os períodos avaliados. O herbicida imazamox não proporcionou controle em até 12 HAA, enquanto que a partir de 24 HAA do herbicida o controle foi eficiente. Não houve uma grande mobilidade da molécula de glyphosate nas plantas de aguapé, sendo necessário um período superior a 24 horas para uma translocação satisfatória. Já para o imazamox um tempo de mínimo de 24 horas após a aplicação do herbicida foi suficiente para que ocorresse a translocação e um posterior controle. Abstract in english Eichhornia crassipes is one of the main weeds found in aquatic environments, being undesirable for many activities. The aim of this study was to evaluate the translocation of glyphosate and imazamox in E. crassipes. Eight intervals were studied for cutting leaves that received herbicides: 2, 4, 6, 8 [...] , 12 and 24 hours after application (HAA), and a treatment with no cutting (untreated). The glyphosate dose was 2,160 g a.e. ha-1 (commercial product - Rodeo) + 0.5% v v-1 Aterbane adhesive spreader and imazamox at 290.4 g i.a. ha-1 (commercial product - Clearcast). The treatments were installed in a completely randomized design with four replications. Glyphosate showed a bad control for all the periods of leaf cutting. The imazamox did not provide control within 12 HAA, while from 24 HAA onward the control was effective. There was not a great mobility of the glyphosate molecule in water hyacinth plants, a period above 24 hours being needed for a satisfactory translocation. For imazamox at least 24 hours were needed after herbicide application for the translocation to occur along with subsequent control.

  7. Crescimento de cultivares de café arábica submetidos a doses do glyphosate Growth of arabica coffee cultivars submitted to glyphosate doses

    OpenAIRE

    A.C França; M.A.M Freitas; C.M.T Fialho; A.A. Silva; M.R Reis; L. Galon; R. Victoria Filho

    2010-01-01

    Avaliaram-se, neste trabalho, os efeitos do glyphosate sobre o crescimento de três cultivares de café arábica. Utilizou-se o esquema fatorial (3 x 5) em delineamento de blocos casualizados, com quatro repetições, sendo os tratamentos compostos por três cultivares de café: Catucaí Amarelo (2 SL), Oeiras (MG-6851) e Topázio (MG-1190) e cinco doses de glyphosate (0; 57,6; 115,2; 230,4; e 460,8 g ha-1). O herbicida foi aplicado quando as plantas de café se apresentavam com 21 pares de folhas e de...

  8. Efeito de adjuvantes adicionados à calda herbicida contendo glyphosate Effect of adjuvants added to herbicide spray containing glyphosate

    OpenAIRE

    Leandro Vargas; Nilson G. Fleck; Marcos M. da Cunha; Ribas A. Vidal

    1997-01-01

    Tentativas de aumentar a fitotoxicidade do herbicida glyphosate através da adição de ácido e/ ou de sulfato de amônio à calda tem sido promissoras. A adição dessas substâncias otimiza as propriedades químicas da calda herbicida, superando efeitos negativos do pH elevado e de ions nela presentes. O objetivo desse trabalho foi investigar o efeito da adição de ácido sulfúrico e/ou de sulfato de amônio à calda herbicida, sobre a eficiência do glyphosate misturado em diluente com alto pH e teores ...

  9. Fenologia da trapoeraba como indicador para tolerância ao herbicida glyphosate / Phenology of bengal dayflower as indicator of glyphosate tolerance

    Scientific Electronic Library Online (English)

    A.C.R, Dias; S.J.P, Carvalho; P.J, Christoffoleti.

    2013-03-01

    Full Text Available Rotineiramente, tem sido desconsiderada a contribuição do estádio de desenvolvimento das espécies de plantas daninhas nas análises de tolerância ou resistência a herbicidas, o que pode resultar em divergências entre a pesquisa teórica e a aplicação prática dos dados. Nesse sentido, este trabalho foi [...] desenvolvido com o objetivo de avaliar a resposta biológica da trapoeraba (Commelina benghalensis), comparativamente ao capim-marmelada (Brachiaria plantaginea), a aplicações de doses do herbicida glyphosate, em seis estádios fenológicos. Dois experimentos foram desenvolvidos em casa de vegetação, submetendo-se plantas de trapoeraba e capim-marmelada ao esquema fatorial de tratamentos 9 x 6, em que nove foram as doses de glyphosate e seis foram os estádios fenológicos das plantas daninhas, variáveis entre a emissão da primeira folha definitiva e o início do florescimento. Por meio do emprego de curvas de dose-resposta e de regressões polinomiais, concluiu-se que o estádio de desenvolvimento da trapoeraba contribui significativamente para o grau de tolerância da espécie ao herbicida glyphosate, de modo que, comparativamente ao capim-marmelada, plantas de trapoeraba tornam-se quatro vezes mais tolerantes ao glyphosate a cada dez unidades de desenvolvimento fenológico na escala BBCH. Essas considerações possuem importante aplicabilidade prática, justificando medidas de controle químico em estádios iniciais do crescimento da trapoeraba. Abstract in english The importance of the phenological development of weeds has been frequently ignored when analyzing plant-herbicide tolerance or resistance, what may result on divergences between theoretical research and practical data application. Thus, this work was carried out to evaluate the biological response [...] of Bengal dayflower (Commelina benghalensis), comparatively to alexandergrass (Brachiaria plantaginea), to the application of different rates of glyphosate, at six phenological stages. Two experiments were developed under greenhouse conditions, with Bengal dayflower and alexandergrass plants being submitted to a 9 x6 factorial scheme, where nine treatments were the glyphosate rates and six, the weed phenological stages, varying between unfolding of the first true leaf and the beginning of flowering. Using dose-response curves and polynomial regressions, it could be concluded that the Bengal dayflower phenological stages significantly contribute to the species'degree of glyphosate-tolerance, since, compared to alexandergrass, Bengal dayflower plants became four times more tolerant to glyphosate at every ten units of phenological development at the BBCH scale. These considerations have an important practical applicability, justifying chemical control measurements at the initial growth stages of Bengal dayflower.

  10. Influência de pontas de pulverização e adjuvantes na deriva em caldas com glyphosate Influence on spray drift of nozzles and adjuvants with a glyphosate spray solution

    Directory of Open Access Journals (Sweden)

    Marco Antonio Gandolfo

    2013-09-01

    Full Text Available O uso inadequado da tecnologia de aplicação de agrotóxicos, relacionados ao uso de pontas de pulverização e adição de adjuvantes, resulta diretamente em um maior risco de deriva. Objetivou-se como trabalho quantificar a deriva gerada por pontas de pulverização com e sem indução de ar, em aplicações de glyphosate e adjuvantes. O experimento foi realizado em túnel de vento, com o herbicida glyphosate isolado ou em mistura com ureia ou adjuvante redutor de deriva (LI700. As coletas foram realizadas, com fios de polietileno, nas distâncias de 5,0; 10,0 e 15,0 m em relação à barra e nas alturas de 0,2; 0,4; 0,6; 0,8 e 1,0 m em relação ao piso do túnel, a deriva foi aferida por meio do processo de condutividade elétrica. Os resultados apresentaram maior deriva nas menores alturas, tendo igual comportamento para todas as caldas e em todas as distâncias. A ponta de jato plano com indução de ar (AVI 110-015 proporcionou menor deriva em relação à ponta jato plano padrão (AXI 110-015, para todas as caldas avaliadas. Para a ponta de jato plano padrão o acréscimo de adjuvante reduziu a deriva para as três distâncias avaliadas em relação à calda contendo somente o herbicida. Já para a ponta de jato plano com indução de ar a ureia elevou a deriva para todas as distâncias em relação às outras caldas. A ureia pode ser utilizada em aplicações com o modelo de ponta jato plano padrão, por diminuir os riscos de deriva.The improper use of pesticide-application technology, related to the use of spray nozzles and the addition of adjuvants, is directly related to a greater risk of drift. This study aimed to quantify the spray drift generated by nozzles, both with and without air induction, in applications of glyphosate and adjuvants. The experiment was conducted in a wind tunnel, using the herbicide, glyphosate, either pure or in combination with urea or a drift-reducing adjuvant (LI700. Collections were made on polyethylene strings, at distances of 5.0, 10.0 and 15.0 m from the spray-boom, and at heights of 0.2, 0.4, 0.6, 0.8 and 1.0 m from the floor of the tunnel; the drift was measured using a process of electrical conductivity. The results showed greater drift at the lower heights, giving the same results for all solutions and at all distances. The flat nozzle with air induction (AVI 110-015 gave a smaller drift relative to the standard flat nozzle (AXI 110-015 for all solutions tested. With the standard flat nozzle, adding an adjuvant reduced the drift at the three distances tested, for the solution containing pure herbicide. For the flat fan nozzle with air induction however, the urea increased drift at all distances compared to other the spray solutions. Urea can be employed in applications where the standard flat tip model is used, as it reduces the risk of drift.

  11. Notch signalling in the paraxial mesoderm is most sensitive to reduced Pofut1 levels during early mouse development

    Directory of Open Access Journals (Sweden)

    Serth Jürgen

    2009-01-01

    Full Text Available Abstract Background The evolutionarily conserved Notch signalling pathway regulates multiple developmental processes in a wide variety of organisms. One critical posttranslational modification of Notch for its function in vivo is the addition of O-linked fucose residues by protein O-fucosyltransferase 1 (POFUT1. In addition, POFUT1 acts as a chaperone and is required for Notch trafficking. Mouse embryos lacking POFUT1 function die with a phenotype indicative of global inactivation of Notch signalling. O-linked fucose residues on Notch can serve as substrates for further sugar modification by Fringe (FNG proteins. Notch modification by Fringe differently affects the ability of ligands to activate Notch receptors in a context-dependent manner indicating a complex modulation of Notch activity by differential glycosylation. Whether the context-dependent effects of Notch receptor glycosylation by FNG reflect different requirements of distinct developmental processes for O-fucosylation by POFUT1 is unclear. Results We have identified and characterized a spontaneous mutation in the mouse Pofut1 gene, referred to as "compact axial skeleton" (cax. Cax carries an insertion of an intracisternal A particle retrotransposon into the fourth intron of the Pofut1 gene and represents a hypomorphic Pofut1 allele that reduces transcription and leads to reduced Notch signalling. Cax mutant embryos have somites of variable size, showed partly abnormal Lfng expression and, consistently defective anterior-posterior somite patterning and axial skeleton development but had virtually no defects in several other Notch-regulated early developmental processes outside the paraxial mesoderm that we analyzed. Conclusion Notch-dependent processes apparently differ with respect to their requirement for levels of POFUT1. Normal Lfng expression and anterior-posterior somite patterning is highly sensitive to reduced POFUT1 levels in early mammalian embryos, whereas other early Notch-dependent processes such as establishment of left-right asymmetry or neurogenesis are not. Thus, it appears that in the presomitic mesoderm (PSM Notch signalling is particularly sensitive to POFUT1 levels. Reduced POFUT1 levels might affect Notch trafficking or overall O-fucosylation. Alternatively, reduced O-fucosylation might preferentially affect sites that are substrates for LFNG and thus important for somite formation and patterning.

  12. Reduced vascular responses to soluble guanylyl cyclase but increased sensitivity to sildenafil in female rats with type 2 diabetes.

    Science.gov (United States)

    Goulopoulou, Styliani; Hannan, Johanna L; Matsumoto, Takayuki; Ogbi, Safia; Ergul, Adviye; Webb, R Clinton

    2015-07-15

    Impaired nitric oxide (NO), soluble guanylyl cyclase (sGC), and cyclic guanosine monophosphate (cGMP) signaling (NO-sGC-cGMP) has been implicated in the pathogenesis of diabetic vascular dysfunction. Efforts to directly target this signaling have led to the development of sGC agonists that activate the heme group of sGC (stimulators) or preferentially activate sGC when the heme is oxidized (activators). In this study, we hypothesized that resistance arteries from female rats with spontaneous type 2 diabetes (Goto-Kakizaki rats, GK) would have reduced vasodilatory responses to heme-dependent sGC activation and increased responses to heme-independent sGC activation compared with control rats (Wistar). Endothelium-dependent and -independent relaxation was assessed in isolated segments from mesenteric resistance arteries (MA) mounted in a wire myograph. GK MA had reduced responses to acetylcholine (pEC50: 7.96 ± 0.06 vs. 7.66 ± 0.05, P 0.05). GK MA had attenuated responses to BAY 41-2272 (heme-dependent sGC stimulator; pEC50: 7.56 ± 0.05 vs. 6.93 ± 0.06, P reproductive age that spontaneously develop type 2 diabetes have increased sensitivity to PDE5 inhibition and reduced responsiveness to sGC activators and stimulators. PMID:25957216

  13. Desiccation species of ground cover with glyphosate formulations

    Directory of Open Access Journals (Sweden)

    Fábio Henrique Krenchinski

    2013-08-01

    Full Text Available The management of coverage species may be accomplished by mechanical or chemical methods. In chemical method nonselective herbicides are used mainly the ones belonging to glyphosate group. The objective of this study was to evaluate phytotoxicity and agronomic efficacy of two formulations with active ingredient glyphosate over desiccation in ground cover species. The present study was conducted in field conditions in Marechal Candido Rondon County, Parana State. Experimental design used was randomized complete blocks with four repetitions in factorial scheme 2x5 (formulations x species, in that the species were white oat, black oat, ryegrass, common vetch and oilseed radish, desiccated by two herbicides: Zapp Qi® (ZQ and Glyphosate 480 Agripec® (GA. Phytotoxicity and agronomic efficacy of coverage species were evaluated. Zapp Qi® has provided greater phytotoxicity and agronomic efficacy of coverage species when compared to Glyphosate 480 Agripec®.  Zapp Qi® at 32 days after desiccation presented the highest values of agronomic efficiency. The only specie that presented 100% of efficacy was oilseed radish.

  14. RHIZOSPHERE ECOLOGY IS ALTERED IN GLYPHOSATE RESISTANT SOYBEAN

    Science.gov (United States)

    The environmental assessment of glyphosate-resistant (GR) soybean on soil- and root-associated microbial communities is not well understood. Changes in the dynamics of soil and rhizosphere microbial community structure may lead to functional consequences with either positive or negative effects on p...

  15. GLYPHOSATE-RESISTANT PALMER AMARANTH (AMARANTHUS PALMERI) CONFIRMED IN GEORGIA

    Science.gov (United States)

    Palmer amaranth is among the three most troublesome weeds in Georgia cotton, peanut, and soybean and is among the top five most troublesome weeds in most other southeastern states. A glyphosate-resistant Palmer amaranth biotype was confirmed in central Georgia. In the field, potassium salt of glyp...

  16. In vivo ³¹P-nuclear magnetic resonance studies of glyphosate uptake, vacuolar sequestration, and tonoplast pump activity in glyphosate-resistant horseweed.

    Science.gov (United States)

    Ge, Xia; d'Avignon, D André; Ackerman, Joseph J H; Sammons, R Douglas

    2014-11-01

    Horseweed (Conyza canadensis) is considered a significant glyphosate-resistant (GR) weed in agriculture, spreading to 21 states in the United States and now found globally on five continents. This laboratory previously reported rapid vacuolar sequestration of glyphosate as the mechanism of resistance in GR horseweed. The observation of vacuole sequestration is consistent with the existence of a tonoplast-bound transporter. (31)P-Nuclear magnetic resonance experiments performed in vivo with GR horseweed leaf tissue show that glyphosate entry into the plant cell (cytosolic compartment) is (1) first order in extracellular glyphosate concentration, independent of pH and dependent upon ATP; (2) competitively inhibited by alternative substrates (aminomethyl phosphonate [AMPA] and N-methyl glyphosate [NMG]), which themselves enter the plant cell; and (3) blocked by vanadate, a known inhibitor/blocker of ATP-dependent transporters. Vacuole sequestration of glyphosate is (1) first order in cytosolic glyphosate concentration and dependent upon ATP; (2) competitively inhibited by alternative substrates (AMPA and NMG), which themselves enter the plant vacuole; and (3) saturable. (31)P-Nuclear magnetic resonance findings with GR horseweed are consistent with the active transport of glyphosate and alternative substrates (AMPA and NMG) across the plasma membrane and tonoplast in a manner characteristic of ATP-binding cassette transporters, similar to those that have been identified in mammalian cells. PMID:25185124

  17. Influência do orvalho e volume de calda de aplicação na eficácia do glyphosate na dessecação de Brachiaria plantaginea / Influence of dew and spray volume on the efficacy of glyphosate for Brachiaria plantaginea burndown

    Scientific Electronic Library Online (English)

    E.S., Roman; L., Vargas; M.C.F., Ribeiro; A.R.M., Luiz.

    2004-09-01

    Full Text Available A eficácia de herbicidas é influenciada por diversos fatores que afetam a absorção e a translocação desses compostos na planta. A absorção de herbicidas pelas plantas, por exemplo, é influenciada, tanto física como biologicamente, pela temperatura e pela umidade relativa do ar dentro do dossel. Com [...] a diminuição da umidade relativa do ar e/ou com o aumento da temperatura, as gotas da pulverização secam mais rapidamente e a absorção do produto diminui, ou até mesmo cessa, afetando o desempenho biológico. Com base nessa premissa, o presente estudo teve como objetivo examinar a influência do orvalho e do volume de calda de aplicação na eficiência de doses de glyphosate para o controle de Brachiaria plantaginea. Foram observadas interações significativas entre volume de calda, orvalho e dose de glyphosate. O volume mais baixo (100 L ha-1) resultou em melhor controle da espécie, especialmente quando o herbicida foi usado na menor dose (90 g ha-1). A presença de orvalho nas folhas causou reduções na atividade do produto, especialmente quando aplicado na menor dose e combinado com maior volume de calda. Abstract in english The efficacy of herbicides is influenced by several factors affecting the absorption and translocation of these compounds in the plant. Herbicide plant absorption, for example, is both physically and biologically influenced by temperature and air relative humidity in the plant canopy. With the reduc [...] tion in relative air humidity and/or increase in temperature, the spray droplets dry more rapidly and the absorption of the herbicide decreases or even stops, affecting the biological performance. Based on that, this research aimed to study the influence of dew and spray volume on the efficacy of glyphosate rates in the control of B. plantaginea. There were significant interactions among volume of water, dew and rate of glyphosate. The lower the water volume, the more effective the glyphosate activity was, especially when applied at the lowest tested rate (90 g ha-1). The presence of dew on the leaves caused reductions in the activity of the product, mainly when the lowest rate was combined with the highest water volume.

  18. Germination test as a fast method to detect glyphosate-resistant sourgrass

    Scientific Electronic Library Online (English)

    Marcos Altomani Neves, Dias; Flavio Eduardo Botelhos, Obara; Natalia, Arruda; Patricia Ribeiro, Cursi; Navara Roberto, Gonçalves; Pedro Jacob, Christoffoleti.

    Full Text Available The occurrence of weed species with different levels of resistance to glyphosate has increasingly spread in agricultural areas. In Brazil, sourgrass is among the main species presenting issues in this regard. Thus, fast and reliable methods to detect glyphosate resistance are of special interest for [...] this specie, either for research or rational management purposes. This study was carried out to verify the feasibility of using the germination test to detect glyphosate resistance in sourgrass. The experiment was conducted with two sourgrass biotypes, with different levels of susceptibility to glyphosate. The seeds were previously imbibed in solutions composed of 0, 0.1875%, 0.25%, 0.75%, 1.5%, 3% and 6% of glyphosate during two periods, five and ten minutes, and submitted to germination tests. The results indicate the germination test as a feasible and time-saving approach to evaluate glyphosate-resistant sourgrass, with results available in seven days.

  19. Equilibrium and kinetic mechanisms of woody biochar on aqueous glyphosate removal.

    Science.gov (United States)

    Mayakaduwa, S S; Kumarathilaka, Prasanna; Herath, Indika; Ahmad, Mahtab; Al-Wabel, Mohammed; Ok, Yong Sik; Usman, Adel; Abduljabbar, Adel; Vithanage, Meththika

    2016-02-01

    We investigated the removal of aqueous glyphosate using woody (dendro) biochar obtained as a waste by product from bioenergy industry. Equilibrium isotherms and kinetics data were obtained by adsorption experiments. Glyphosate adsorption was strongly pH dependent occurring maximum in the pH range of 5-6. The protonated amino moiety of the glyphosate molecule at this pH may interact with ? electron rich biochar surface via ?-? electron donor-acceptor interactions. Isotherm data were best fitted to the Freundlich and Temkin models indicating multilayer sorption of glyphosate. The maximum adsorption capacity of dendro biochar for glyphosate was determined by the isotherm modeling to be as 44 mg/g. Adsorption seemed to be quite fast, reaching the equilibrium glyphosate removal. PMID:26340852

  20. Glyphosate sorption and desorption in soils with distinct phosphorus levels

    Energy Technology Data Exchange (ETDEWEB)

    Prata, Fabio [BIOAGRI Labs., Piracicaba, SP (Brazil). Div. de Quimica. Lab. de Radioquimica; Cardinali, Vanessa Camponez do Brasil; Tornisielo, Valdemar Luiz; Regitano, Jussara Borges [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz. Dept. de Ciencias Exatas; Lavorenti, Arquimedes [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Secao de Toxicologia

    2003-03-01

    The sorption of glyphosate by soils occurs due to the inner sphere complex formation with metals of soil oxides, which are related to the soil phosphate adsorption capacity. The aim of this study was to evaluate the effects of increasing rates of phosphorus on sorption and desorption of glyphosate in three soils with different mineralogical attributes. Soils were a Rhodic Kandiudalf, an Anionic Acrudox and a Typic Humaquept. Soil samples were amended with Kh{sub 2}PO{sub 4} at equivalent rates of 0; 1,000; 5,000; 20,000 and 50,000 kg ha{sup -1} of P{sub 2}O{sub 5}, which are high from the agricultural point of view, but necessary in order to perform sorption and desorption studies. The experimental design consisted of a completely randomized factorial: 2 soils x 5 phosphorus rates and 3 replicates. For the sorption experiments, five glyphosate solutions were employed (0.42; 0.84; 1.68; 3.36 and 6.72 mg L{sup -1}), with a {sup 14}C radioactivity of 0.233 kBq mL{sup -1}. Four steps of the desorption procedures withCaCl{sub 2} 0.01 mol L{sup -1} and one extraction with Mehlich 3 were performed only at one concentration (0.84 mol L{sup -1}). Soil samples were afterwards biologically oxidized to establish the radioactive balance. Glyphosate competes with phosphorus for specific sorption sites, but this competition becomes important when phosphorus is present at rates higher than 1,000 mg dm{sup -3}. Moreover, a small amount of applied glyphosate was extracted (<10%), and the extraction increased with increasing soil phosphorus content. (author)

  1. Glyphosate sorption and desorption in soils with distinct phosphorus levels

    Directory of Open Access Journals (Sweden)

    Prata Fábio

    2003-01-01

    Full Text Available The sorption of glyphosate by soils occurs due to the inner sphere complex formation with metals of soil oxides, which are related to the soil phosphate adsorption capacity. The aim of this study was to evaluate the effects of increasing rates of phosphorus on sorption and desorption of glyphosate in three soils with different mineralogical attributes. Soils were a Rhodic Kandiudalf, an Anionic Acrudox and a Typic Humaquept. Soil samples were amended with KH2PO4 at equivalent rates of 0; 1,000; 5,000; 20,000 and 50,000 kg ha-1 of P2O5, which are high from the agricultural point of view, but necessary in order to perform sorption and desorption studies. The experimental design consisted of a completely randomized factorial: 2 soils x 5 phosphorus rates and 3 replicates. For the sorption experiments, five glyphosate solutions were employed (0.42; 0.84; 1.68; 3.36 and 6.72 mg L-1, with a 14C radioactivity of 0.233 kBq mL-1. Four steps of the desorption procedure with CaCl2 0.01 mol L-1 and one extraction with Mehlich 3 were performed only at one concentration (0.84 mol L-1. Soil samples were afterwards biologically oxidized to establish the radioactive balance. Glyphosate competes with phosphorus for specific sorption sites, but this competition becomes important when phosphorus is present at rates higher than 1,000 mg dm-3. Moreover, a small amount of applied glyphosate was extracted (<10%, and the extraction increased with increasing soil phosphorus content.

  2. Glyphosate sorption and desorption in soils with distinct phosphorus levels

    International Nuclear Information System (INIS)

    The sorption of glyphosate by soils occurs due to the inner sphere complex formation with metals of soil oxides, which are related to the soil phosphate adsorption capacity. The aim of this study was to evaluate the effects of increasing rates of phosphorus on sorption and desorption of glyphosate in three soils with different mineralogical attributes. Soils were a Rhodic Kandiudalf, an Anionic Acrudox and a Typic Humaquept. Soil samples were amended with Kh2PO4 at equivalent rates of 0; 1,000; 5,000; 20,000 and 50,000 kg ha-1 of P2O5, which are high from the agricultural point of view, but necessary in order to perform sorption and desorption studies. The experimental design consisted of a completely randomized factorial: 2 soils x 5 phosphorus rates and 3 replicates. For the sorption experiments, five glyphosate solutions were employed (0.42; 0.84; 1.68; 3.36 and 6.72 mg L-1), with a 14C radioactivity of 0.233 kBq mL-1. Four steps of the desorption procedures withCaCl2 0.01 mol L-1 and one extraction with Mehlich 3 were performed only at one concentration (0.84 mol L-1). Soil samples were afterwards biologically oxidized to establish the radioactive balance. Glyphosate competes with phosphorus for specific sorption sites, but this competition becomes important when phosphorus is present at rates higher than 1,000 mg dm-3. Moreover, a small amount of applied glyphosate was extracted (<10%), and the extraction increased with increasing soil phosphorus content. (author)

  3. Highly sensitive determination of reduced glutathione based on a cobalt nanoparticle implanted-modified indium tin oxide electrode.

    Science.gov (United States)

    Wang, Tong; Su, Wen; Xiao, Zhengjun; Hao, Shuang; Li, Yuanchun; Hu, Jingbo

    2015-08-01

    Cobalt nanoparticle modified indium tin oxide (CoNP/ITO) electrodes fabricated by ion implantation were applied for the detection of reduced glutathione (GSH). The CoNP/ITO electrode was characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) detector and X-ray photoelectron spectroscopy (XPS). The assay performance with regard to GSH were evaluated by cyclic voltammetry (CV) and chronoamperometry (I-t). The proposed sensor exhibited a much higher electrocatalytic activity toward the oxidation of GSH than the bare ITO electrode, with a detection limit of 5 nM. The CoNP/ITO electrode showed enhanced electrocatalytic properties, high sensitivity, good long-term stability and reproducibility as well as a rapid response to detect GSH. In addition, the CoNP/ITO electrode was also used to analyse the GSH concentration in eye drop samples, and the results were in good agreement with the labelled values. PMID:26034785

  4. Introduction of a methoxymethyl side chain into p-phenylenediamine attenuates its sensitizing potency and reduces the risk of allergy induction

    Energy Technology Data Exchange (ETDEWEB)

    Goebel, Carsten, E-mail: goebel.c.1@pg.com [The Procter and Gamble Co., Central Product Safety and Communications, Darmstadt (Germany); Troutman, John [The Procter and Gamble Co., Central Product Safety, Cincinnati, OH (United States); Hennen, Jenny [Dept. of Environmental Toxicology, Trier University, Trier (Germany); Rothe, Helga; Schlatter, Harald [The Procter and Gamble Co., Central Product Safety and Communications, Darmstadt (Germany); Gerberick, G. Frank [The Procter and Gamble Co., Central Product Safety, Cincinnati, OH (United States); Blömeke, Brunhilde [Dept. of Environmental Toxicology, Trier University, Trier (Germany)

    2014-02-01

    The strong sensitizing potencies of the most important primary intermediates of oxidative hair dyes, p-phenylenediamine (PPD) and p-toluylenediamine (PTD, i.e. 2-methyl-PPD) are well established. They are considered as the key sensitizers in hair dye allergic contact dermatitis. While modification of their molecular structure is expected to alter their sensitizing properties, it may also impair their color performance. With introduction of a methoxymethyl side chain we found the primary intermediate 2-methoxymethyl-p-phenylenediamine (ME-PPD) with excellent hair coloring performance but significantly reduced sensitizing properties compared to PPD and PTD: In vitro, ME-PPD showed an attenuated innate immune response when analyzed for its protein reactivity and dendritic cell activation potential. In vivo, the effective concentration of ME-PPD necessary to induce an immune response 3-fold above vehicle control (EC3 value) in the local lymph node assay (LLNA) was 4.3%, indicating a moderate skin sensitizing potency compared to values of 0.1 and 0.17% for PPD and PTD, respectively. Finally, assessing the skin sensitizing potency of ME-PPD under consumer hair dye usage conditions through a quantitative risk assessment (QRA) indicated an allergy induction risk negligible compared to PPD or PTD. - Highlights: • Methoxymethyl side chain in p-phenylenediamine reduces its strong skin sensitizing properties. • Reduced protein reactivity and dendritic cell activation. • Reduced skin sensitizing potency in local lymph node assay (LLNA). • Negligible allergy induction risk under hair dye usage conditions.

  5. Introduction of a methoxymethyl side chain into p-phenylenediamine attenuates its sensitizing potency and reduces the risk of allergy induction

    International Nuclear Information System (INIS)

    The strong sensitizing potencies of the most important primary intermediates of oxidative hair dyes, p-phenylenediamine (PPD) and p-toluylenediamine (PTD, i.e. 2-methyl-PPD) are well established. They are considered as the key sensitizers in hair dye allergic contact dermatitis. While modification of their molecular structure is expected to alter their sensitizing properties, it may also impair their color performance. With introduction of a methoxymethyl side chain we found the primary intermediate 2-methoxymethyl-p-phenylenediamine (ME-PPD) with excellent hair coloring performance but significantly reduced sensitizing properties compared to PPD and PTD: In vitro, ME-PPD showed an attenuated innate immune response when analyzed for its protein reactivity and dendritic cell activation potential. In vivo, the effective concentration of ME-PPD necessary to induce an immune response 3-fold above vehicle control (EC3 value) in the local lymph node assay (LLNA) was 4.3%, indicating a moderate skin sensitizing potency compared to values of 0.1 and 0.17% for PPD and PTD, respectively. Finally, assessing the skin sensitizing potency of ME-PPD under consumer hair dye usage conditions through a quantitative risk assessment (QRA) indicated an allergy induction risk negligible compared to PPD or PTD. - Highlights: • Methoxymethyl side chain in p-phenylenediamine reduces its strong skin sensitizing properties. • Reduced protein reactivity and dendritic cell activation. • Reduced skin sensitizing potency in local lymph node assay (LLNA). • Negligible allergy induction risk under hair dye usage conditions

  6. miR-134 in extracellular vesicles reduces triple-negative breast cancer aggression and increases drug sensitivity.

    Science.gov (United States)

    O'Brien, Keith; Lowry, Michelle C; Corcoran, Claire; Martinez, Vanesa G; Daly, Melissa; Rani, Sweta; Gallagher, William M; Radomski, Marek W; MacLeod, Roderick A F; O'Driscoll, Lorraine

    2015-10-20

    Exosomes (EVs) have relevance in cell-to-cell communication carrying pro-tumorigenic factors that participate in oncogenesis and drug resistance and are proposed to have potential as self-delivery systems. Advancing on our studies of EVs in triple-negative breast cancer, here we more comprehensively analysed isogenic cell line variants and their EV populations, tissues cell line variants and their EV populations, as well as breast tumour and normal tissues. Profiling 384 miRNAs showed EV miRNA content to be highly representative of their cells of origin. miRNAs most substantially down-regulated in aggressive cells and their EVs originated from 14q32. Analysis of miR-134, the most substantially down-regulated miRNA, supported its clinical relevance in breast tumours compared to matched normal breast tissue. Functional studies indicated that miR-134 controls STAT5B which, in turn, controls Hsp90. miR-134 delivered by direct transfection into Hs578Ts(i)8 cells (in which it was greatly down-regulated) reduced STAT5B, Hsp90, and Bcl-2 levels, reduced cellular proliferation, and enhanced cisplatin-induced apoptosis. Delivery via miR-134-enriched EVs also reduced STAT5B and Hsp90, reduced cellular migration and invasion, and enhanced sensitivity to anti-Hsp90 drugs. While the differing effects achieved by transfection or EV delivery are likely to be, at least partly, due to specific amounts of miR-134 delivered by these routes, these EV-based studies identified miRNA-134 as a potential biomarker and therapeutic for breast cancer. PMID:26416415

  7. Chronic sleep restriction disrupts sleep homeostasis and behavioral sensitivity to alcohol by reducing the extracellular accumulation of adenosine.

    Science.gov (United States)

    Clasadonte, Jerome; McIver, Sally R; Schmitt, Luke I; Halassa, Michael M; Haydon, Philip G

    2014-01-29

    Sleep impairments are comorbid with a variety of neurological and psychiatric disorders including depression, epilepsy, and alcohol abuse. Despite the prevalence of these disorders, the cellular mechanisms underlying the interaction between sleep disruption and behavior remain poorly understood. In this study, the impact of chronic sleep loss on sleep homeostasis was examined in C57BL/6J mice following 3 d of sleep restriction. The electroencephalographic power of slow-wave activity (SWA; 0.5-4 Hz) in nonrapid eye movement (NREM) sleep and adenosine tone were measured during and after sleep restriction, and following subsequent acute sleep deprivation. During the first day of sleep restriction, SWA and adenosine tone increased, indicating a homeostatic response to sleep loss. On subsequent days, SWA declined, and this was accompanied by a corresponding reduction in adenosine tone caused by a loss of one source of extracellular adenosine. Furthermore, the response to acute sleep deprivation (6 h) was significantly attenuated in sleep-restricted mice. These effects were long-lasting with reduced SWA and adenosine tone persisting for at least 2 weeks. To investigate the behavioral consequences of chronic sleep restriction, sensitivity to the motor-impairing effects of alcohol was also examined. Sleep-restricted mice were significantly less sensitive to alcohol when tested 24 h after sleep restriction, an effect that persisted for 4 weeks. Intracerebroventricular infusion of an adenosine A1 receptor antagonist produced a similar decrease in sensitivity to alcohol. These results suggest that chronic sleep restriction induces a sustained impairment in adenosine-regulated sleep homeostasis and consequentially impacts the response to alcohol. PMID:24478367

  8. Altering second-order configurations reduces the adaptation effects on early face-sensitive event-related potential components

    Directory of Open Access Journals (Sweden)

    Kornél Németh

    2014-06-01

    Full Text Available The spatial distances among the features of a face are commonly referred to as second-order relations, and the coding of these properties is often regarded as a cornerstone in face recognition. Previous studies have provided mixed results regarding whether the N170, a face-sensitive component of the event-related potential, is sensitive to second-order relations. Here we investigated this issue in a gender discrimination paradigm following long-term (5 seconds adaptation to normal or vertically stretched male and female faces, considering that the latter manipulation substantially alters the position of the inner facial features. Gender-ambiguous faces were more likely judged to be female following adaptation to a male face and vice versa. This aftereffect was smaller but statistically significant after being adapted to vertically stretched when compared to unstretched adapters. Event-related potential recordings revealed that adaptation effects measured on the amplitude of the N170 show strong modulations by the second-order relations of the adapter: reduced N170 amplitude was observed, however, this reduction was smaller in magnitude after being adapted to stretched when compared to unstretched faces. These findings suggest early face-processing, as reflected in the N170 component, proceeds by extracting the spatial relations of inner facial features.

  9. Lack of interaction between glyphosate and fungicide treatments on Rhizoctonia crown and root rot in glyphosate-resistant sugarbeet

    Science.gov (United States)

    A field experiment was conducted in 2008 and 2009 in the Saginaw Valley region of Michigan to determine if there were potential interactions between applications of glyphosate and the fungicide azoxystrobin and to determine the effectiveness of foliar and in-furrow azoxystrobin applications when Rhi...

  10. MANAGING GLYPHOSATE-RESISTANT PALMER AMARANTH (AMARANTHUS PALMERI) IN GEORGIA COTTON (GOSSYPIUM HIRSUTUM)

    Science.gov (United States)

    Studies were conducted in GA to evaluate control programs on a population of glyphosate-resistant Palmer amaranth. Glyphosate at 0.84 (1X use rate), 1.68, and 3.36 kg ae ha-1 controlled the weed >31%. Pendimethalin (0.94 kg ai ha-1) plus fluometuron (1.12 kg ai ha-1) PRE, glyphosate 0.84 kg POST, ...

  11. Annual Glyphosate Treatments Alter Growth of Unaffected Bentgrass (Agrostis) Weeds and Plant Community Composition

    OpenAIRE

    Ahrens, Collin W.; Auer, Carol A.

    2012-01-01

    Herbicide resistance is becoming more common in weed ecotypes and crop species including turfgrasses, but current gaps in knowledge limit predictive ecological risk assessments and risk management plans. This project examined the effect of annual glyphosate applications on the vegetative growth and reproductive potential of two weedy bentgrasses, creeping bentgrass (CB) and redtop (RT), where the glyphosate resistance (GR) trait was mimicked by covering the bentgrass plants during glyphosate ...

  12. BEHAVIOR OF THE NON-SELECTIVE HERBICIDE GLYPHOSATE IN AGRICULTURAL SOIL

    OpenAIRE

    Abdul Jabbar Al-Rajab; Othman M. Hakami

    2014-01-01

    Glyphosate [N-phosphonomethyl]glycine is a systematic, non-selective, organophosphorus herbicide used worldwide in agriculture and industrial zones. Following its application, residues of glyphosate can threaten soil or aquatic organisms in adjacent water. In this study, we followed the degradation, stabilization, remobilization and leaching of 14C-glyphosate in three agricultural soils in laboratory incubations and in lysimeters under field condition...

  13. Cancer Incidence among Glyphosate-Exposed Pesticide Applicators in the Agricultural Health Study

    OpenAIRE

    DE ROOS, ANNECLAIRE J.; Blair, Aaron; Rusiecki, Jennifer A; Hoppin, Jane A; Svec, Megan; Dosemeci, Mustafa; Sandler, Dale P.; Alavanja, Michael C.

    2004-01-01

    Glyphosate is a broad-spectrum herbicide that is one of the most frequently applied pesticides in the world. Although there has been little consistent evidence of genotoxicity or carcinogenicity from in vitro and animal studies, a few epidemiologic reports have indicated potential health effects of glyphosate. We evaluated associations between glyphosate exposure and cancer incidence in the Agricultural Health Study (AHS), a prospective cohort study of 57,311 licensed pesticide applicators in...

  14. Degradation of the Herbicide Glyphosate by Members of the Family Rhizobiaceae

    OpenAIRE

    Liu, C.-M.; McLean, P A; Sookdeo, C. C.; Cannon, F C

    1991-01-01

    Several strains of the family Rhizobiaceae were tested for their ability to degrade the phosphonate herbicide glyphosate (isopropylamine salt of N-phosphonomethylglycine). All organisms tested (seven Rhizobium meliloti strains, Rhizobium leguminosarum, Rhizobium galega, Rhizobium trifolii, Agrobacterium rhizogenes, and Agrobacterium tumefaciens) were able to grow on glyphosate as the sole source of phosphorus in the presence of the aromatic amino acids, although growth on glyphosate was not a...

  15. Clastogenic Effects of Glyphosate in Bone Marrow Cells of Swiss Albino Mice

    OpenAIRE

    Yogeshwer Shukla; Madhulika Singh; Smita Srivastava; Sahdeo Prasad

    2009-01-01

    Glyphosate (N-(phosphonomethyl) glycine, C3H8NO5P), a herbicide, used to control unwanted annual and perennial plants all over the world. Nevertheless, occupational and environmental exposure to pesticides can pose a threat to nontarget species including human beings. Therefore, in the present study, genotoxic effects of the herbicide glyphosate were analyzed by measuring chromosomal aberrations (CAs) and micronuclei (MN) in bone marrow cells of Swiss albino mice. A single dose of glyphosate ...

  16. An intercomparison study of the determination of glyphosate, chlormequat and mepiquat residues in wheat

    DEFF Research Database (Denmark)

    Andersen, Jens Hinge; Bille, Rikke; Granby, Kit

    2007-01-01

    An intercomparison study of the determinations of glyphosate, chlormequat and mepiquat residues in cereals was performed. Four samples comprising one blank, two incurred and one spiked sample were sent to six participating laboratories. For glyphosate, two laboratories reported considerably lower results than the other four. One of the two laboratories with low results also reported low recoveries. The results of a sample spiked with 0.80 mg kg(-1) glyphosate and an incurred sample, ranged from ...

  17. Utilization of glyphosate as phosphate source: biochemistry and genetics of bacterial carbon-phosphorous lyase

    DEFF Research Database (Denmark)

    Hove-Jensen, Bjarne; Zechel, David L; Jochimsen, Bjarne

    2014-01-01

    After several decades of use of glyphosate, the active ingredient in weed killers such as Roundup, in fields, forests, and gardens, the biochemical pathway of transformation of glyphosate phosphorus to a useful phosphorus source for microorganisms has been disclosed. Glyphosate is a member of a large group of chemicals, phosphonic acids or phosphonates, which are characterized by a carbon-phosphorus bond. This is in contrast to the general phosphorus compounds utilized and metabolized by microor...

  18. EFECTOS LETALES Y SUBLETALES DEL GLIFOSATO (ROUNDUP® ACTIVO) EN EMBRIONES DE ANUROS COLOMBIANOS / Lethal and Sublethal Effects of Glyphosate (Roundup® Active) to Embryos of Colombian Anurans

    Scientific Electronic Library Online (English)

    TEÓFILA MARÍA, TRIANA VELÁSQUEZ; CLAUDIA MARSELA, MONTES ROJAS; MANUEL HERNANDO, BERNAL BAUTISTA.

    2013-08-01

    Full Text Available El glifosato es un herbicida usado en la agricultura que puede afectar especies no blanco. El objetivo del trabajo fue determinar los efectos letales (concentración letal media - CL50) y subletales (cambios en el tamaño corporal y desarrollo) del glifosato (Roundup® Activo) sobre embriones de cuatro [...] especies de anuros expuestos durante 96 horas en pruebas de laboratorio y microcosmos. En laboratorio, la especie más tolerante fue Engystomops pustulosus (CL50 = 3033,18 µg a.e./L) y la más sensible Rhinella marina (CL50 = 1421,46 µg a.e./L), la cual mostró una reducción significativa en el tamaño corporal y retrasos en el desarrollo de los individuos. Las demás especies tuvieron un CL50 intermedio (Rhinella humboldti = 2899,36 µga.e./L; Hypsiboas crepitans = 2151,88 µg a.e./L). En todos los casos el CL50 fue menor a la concentración empleada en campo (5392,92 µg a.e./ L) indicando un efecto tóxico alto. En los microcosmos, los embriones de E. pustulosus fueron los más tolerantes (CL50 = 19,41 kg a.e./ha), mientras que los de R. humboldti los más sensibles (CL50 = 10,61 kg a.e./ha). Sin embargo, todas las especies tuvieron un CL50 superiora la concentración asperjada en campo (3,69 kg a.e./ ha), mostrando un efecto tóxico leve, y no hubo diferencias en el tamaño corporalni en el desarrollo de los individuos. Este resultado muestra que el glifosato, en su presentación comercial como Roundup® Activo, genera una mortalidad moderada en los embriones de anuros. Abstract in english Glyphosate is an herbicide widely used in agriculture, which may affect non-target species. The aim of this study was to determine the lethal (Median lethal concentration - LC50) and sublethal effects (changes on body size and development) of glyphosate (Roundup® Active) to embryos of four anuran sp [...] ecies, exposed during 96 hours under laboratory and microcosmtests. Under laboratory conditions, Engystomops pustulosus was the most tolerant species (LC50 = 3033,18 µg a.e./L) and Rhinella marina was the most sensitive (LC50 = 1421,46 µg a.e./L), which also showed a delayed development and significantly reduced body size. The other species had an intermediate LC50 (Rhinella humboldti = 2899,54 µg a.e./L; Hypsiboas crepitans = 2151,88 µg a.e./L). In all cases, the laboratory LC50 was lower than the concentration used in field (5392,92 µg a.e./L), indicating a high toxic effect. In the microcosm tests, embryos of E. pustulosus were the most tolerant (LC50 = 19,41 kg a.e./ha), while R. humboldti were the most sensitive (LC50 = 10,61 kg a.e./ha). In this case, all four study species had a higher LC50 than the concentration sprayed in field (3,69 kg a.e./ ha), so a lower lethal effect, and there were no significant differences in body size and development. This result shows that the glyphosate, as the commercial presentation Roundup® Active, produce a moderate mortality on anuran embryos.

  19. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    Energy Technology Data Exchange (ETDEWEB)

    Novak, K. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)]. E-mail: kristopher.novak@wsl.ch; Schaub, M. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Fuhrer, J. [Swiss Federal Research Station for Agroecology and Agriculture FAL, 8046 Zurich (Switzerland); Skelly, J.M. [Department of Plant Pathology, The Pennsylvania State University, University Park, PA 16802 (United States); Hug, C. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Landolt, W. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Bleuler, P. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Kraeuchi, N. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)

    2005-07-15

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures.

  20. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    International Nuclear Information System (INIS)

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures

  1. BEHAVIOR OF THE NON-SELECTIVE HERBICIDE GLYPHOSATE IN AGRICULTURAL SOIL

    Directory of Open Access Journals (Sweden)

    Abdul Jabbar Al-Rajab

    2014-01-01

    Full Text Available Glyphosate [N-phosphonomethyl]glycine is a systematic, non-selective, organophosphorus herbicide used worldwide in agriculture and industrial zones. Following its application, residues of glyphosate can threaten soil or aquatic organisms in adjacent water. In this study, we followed the degradation, stabilization, remobilization and leaching of 14C-glyphosate in three agricultural soils in laboratory incubations and in lysimeters under field conditions. Glyphosate degradation was relatively rapid with a half-life of 14.5 days in the silt clay loam soil incubated at 20°C. Glyphosate’s degradation product, Aminomethylphosphonic Acid (AMPA, represented more than 85% of residues after 80 days of laboratory incubation. Leaching of glyphosate in lysimeters of three different investigated soils under outdoor conditions was very slow, less than 1% of the initial applied amount has been detected in the leachates after 100 days of experimentation. Glyphosate rapidly formed non-extractable residues after treatment. In summary, glyphosate was removed from soil very rapidly and its leaching seems to be very slow regardless the type of treated soil. On the other hand, the contamination risk of groundwater with its metabolite AMPA at long term is probably due to the release of the non-extractable residues.

  2. Cloning and sequencing of the genes involved in glyphosate utilization by Pseudomonas pseudomallei.

    OpenAIRE

    Peñaloza-Vazquez, A; Mena, G L; Herrera-Estrella, L.; Bailey, A.M.

    1995-01-01

    Thirty-four strains of Pseudomonas pseudomallei isolated from soil were selected for their ability to degrade the phosphonate herbicide glyphosate. All strains tested were able to grow on glyphosate as the only phosphorus source without the addition of aromatic amino acids. One of these strains, P. pseudomallei 22, showed 50% glyphosate degradation in 40 h in glyphosate medium. From a genomic library of this strain constructed in pUC19, we have isolated a plasmid carrying a 3.0-kb DNA fragmen...

  3. Import of a precursor protein into chloroplasts is inhibited by the herbicide glyphosate

    OpenAIRE

    Della-Cioppa, Guy; Kishore, Ganesh M.

    1988-01-01

    Import of the precursor to 5-enolpyruvylshikimate-3-phosphate synthase (pEPSPS) into chloroplasts is inhibited by the herbicide glyphosate. Inhibition of import is maximal at glyphosate concentrations of ?10 ?m and occurs only when pEPSPS is present as a ternary complex of enzyme–shikimate-3-phosphate–glyphosate. Glyphosate alone had no effect on the import of pEPSPS since it is not known to interact with the enzyme in the absence of shikimate-3-phosphate. Experiments with wild-type and glyph...

  4. The Fate and Transport of Glyphosate and AMPA into Surface Waters of Agricultural Watersheds

    Science.gov (United States)

    Coupe, R.; Kalkhoff, S.; Capel, P.; Gregoire, C.

    2010-12-01

    Glyphosate [N-(phosphonomethyl)glycine] is a herbicide used widely throughout the world in the production of many crops, but is particularly heavily used on crops which are genetically modified to be glyphosate tolerant: predominately soybeans, corn, potatoes, and cotton. Glyphosate is used extensively in almost all agricultural areas of the United States, and annual application has increased from less than 10,000 Mg in 1992 to more than 80,000 Mg in 2007. The greatest areal use is in the Midwest where glyphosate is applied on genetically modified corn and soybeans. Although use is increasing, the characterization of glyphosate transport on the watershed scale is lacking. Glyphosate, and its degradate AMPA [aminomethylphosphoric acid], was frequently detected in the surface waters of four agricultural watersheds. The load as a percent of use of glyphosate ranged from 0.009 to 0.86 percent and can be related to three factors: source strength, hydrology, and flowpath. Glyphosate use within a watershed results in some occurrence in surface water at the part per billion level; however watersheds most at risk for the offsite transport of glyphosate are those with high application rates, rainfall that results in overland runoff, and a flowpath that does not include transport through the soil.

  5. Urban contributions of glyphosate and its degradate AMPA to streams in the United States

    Science.gov (United States)

    Kolpin, D.W.; Thurman, E.M.; Lee, E.A.; Meyer, M.T.; Furlong, E.T.; Glassmeyer, S.T.

    2006-01-01

    Glyphosate is the most widely used herbicide in the world, being routinely applied to control weeds in both agricultural and urban settings. Microbial degradation of glyphosate produces aminomethyl phosphonic acid (AMPA). The high polarity and water-solubility of glyphosate and AMPA has, until recently, made their analysis in water samples problematic. Thus, compared to other herbicides (e.g. atrazine) there are relatively few studies on the environmental occurrence of glyphosate and AMPA. In 2002, treated effluent samples were collected from 10 wastewater treatment plants (WWTPs) to study the occurrence of glyphosate and AMPA. Stream samples were collected upstream and downstream of the 10 WWTPs. Two reference streams were also sampled. The results document the apparent contribution of WWTP effluent to stream concentrations of glyphosate and AMPA, with roughly a two-fold increase in their frequencies of detection between stream samples collected upstream and those collected downstream of the WWTPs. Thus, urban use of glyphosate contributes to glyphosate and AMPA concentrations in streams in the United States. Overall, AMPA was detected much more frequently (67.5%) compared to glyphosate (17.5%). ?? 2005 Elsevier B.V. All rights reserved.

  6. Neutralization of the antimicrobial effect of glyphosate by humic acid in vitro.

    Science.gov (United States)

    Shehata, Awad A; Kühnert, Manfred; Haufe, Svent; Krüger, Monika

    2014-06-01

    In the present study, the neutralization ability of the antimicrobial effect of glyphosate by different humic acids was investigated. The minimal inhibitory concentrations of glyphosate for different bacteria such as Bacillus badius, Bifidobacterium adolescentis, Escherichia coli, E. coli 1917 strain Nissle, Enterococcus faecalis, Enterococcus faecium, Salmonella enteritidis and Salmonella typhimurium were determined in the presence or absence of different concentrations of humic acid (0.25, 0.5 and 1.0 mg mL(-1)). Our findings indicated that humic acids inhibited the antimicrobial effect of glyphosate on different bacteria. This information can help overcome the negative impact of glyphosate residues in feed and water. PMID:24268342

  7. Sevoflurane Preconditioning Reduces Intestinal Ischemia-Reperfusion Injury: Role of Protein Kinase C and Mitochondrial ATP-Sensitive Potassium Channel.

    Science.gov (United States)

    Liu, Chuiliang; Liu, Yanhui; Shen, Zhiwen; Miao, Liping; Zhang, Kun; Wang, Fei; Li, Yujuan

    2015-01-01

    Ischemic preconditioning (IPC) has been considered to be a potential therapy to reduce ischemia-reperfusion injury (IRI) since the 1980s. Our previous study indicated that sevoflurane preconditioning (SPC) also reduced intestinal IRI in rats. However, whether the protective effect of SPC is similar to IPC and the mechanisms of SPC are unclear. Thus, we compared the efficacy of SPC and IPC against intestinal IRI and the role of protein kinase C (PKC) and mitochondrial ATP-sensitive potassium channel (mKATP) in SPC. A rat model of intestinal IRI was used in this study. The superior mesenteric artery (SMA) was clamped for 60 min followed by 120 min of reperfusion. Rats with IPC underwent three cycles of SMA occlusion for 5 min and reperfusion for 5 min before intestinal ischemia. Rats with SPC inhaled sevoflurane at 0.5 minimum alveolar concentration (MAC) for 30 min before the intestinal ischemic insult. Additionally, the PKC inhibitor Chelerythrine (CHE) or mKATP inhibitor 5-Hydroxydecanoic (5-HD) was injected intraperitoneally before sevoflurane inhalation. Both SPC and IPC ameliorated intestinal IRI-induced histopathological changes, decreased Chiu's scores, reduced terminal deoxyribonucleotide transferase-mediated dUTP nick end labeling (TUNEL) positive cells in the epithelium, and inhibited the expression of malondialdehyde (MDA) and tumor necrosis factor-? (TNF-?). These protective effects of SPC were similar to those of IPC. Pretreatment with PKC or mKATP inhibitor abolished SPC-induced protective effects by increasing Chiu's scores, down-regulated the expression of Bcl-2 and activated caspase-3. Our results suggest that pretreatment with 0.5 MAC sevoflurane is as effective as IPC against intestinal IRI. The activation of PKC and mKATP may be involved in the protective mechanisms of SPC. PMID:26505750

  8. Sevoflurane Preconditioning Reduces Intestinal Ischemia-Reperfusion Injury: Role of Protein Kinase C and Mitochondrial ATP-Sensitive Potassium Channel

    Science.gov (United States)

    Shen, Zhiwen; Miao, Liping; Zhang, Kun; Wang, Fei; Li, Yujuan

    2015-01-01

    Ischemic preconditioning (IPC) has been considered to be a potential therapy to reduce ischemia-reperfusion injury (IRI) since the 1980s. Our previous study indicated that sevoflurane preconditioning (SPC) also reduced intestinal IRI in rats. However, whether the protective effect of SPC is similar to IPC and the mechanisms of SPC are unclear. Thus, we compared the efficacy of SPC and IPC against intestinal IRI and the role of protein kinase C (PKC) and mitochondrial ATP-sensitive potassium channel (mKATP) in SPC. A rat model of intestinal IRI was used in this study. The superior mesenteric artery (SMA) was clamped for 60 min followed by 120 min of reperfusion. Rats with IPC underwent three cycles of SMA occlusion for 5 min and reperfusion for 5 min before intestinal ischemia. Rats with SPC inhaled sevoflurane at 0.5 minimum alveolar concentration (MAC) for 30 min before the intestinal ischemic insult. Additionally, the PKC inhibitor Chelerythrine (CHE) or mKATP inhibitor 5-Hydroxydecanoic (5-HD) was injected intraperitoneally before sevoflurane inhalation. Both SPC and IPC ameliorated intestinal IRI-induced histopathological changes, decreased Chiu’s scores, reduced terminal deoxyribonucleotide transferase-mediated dUTP nick end labeling (TUNEL) positive cells in the epithelium, and inhibited the expression of malondialdehyde (MDA) and tumor necrosis factor-? (TNF-?). These protective effects of SPC were similar to those of IPC. Pretreatment with PKC or mKATP inhibitor abolished SPC—induced protective effects by increasing Chiu’s scores, down-regulated the expression of Bcl-2 and activated caspase-3. Our results suggest that pretreatment with 0.5 MAC sevoflurane is as effective as IPC against intestinal IRI. The activation of PKC and mKATP may be involved in the protective mechanisms of SPC. PMID:26505750

  9. Caracteres anatômicos de duas espécies de trapoeraba e a eficiência do glyphosate Anatomical features of two dayflower species (Commelina spp. on glyphosate efficacy

    Directory of Open Access Journals (Sweden)

    I.C. Santos

    2002-04-01

    Full Text Available O gênero Commelina engloba espécies de plantas daninhas de difícil controle em diversas culturas, principalmente onde o herbicida glyphosate tem sido utilizado com elevada freqüência. Este trabalho foi conduzido com o objetivo de avaliar diferenças entre caracteres anatômicos de Commelina benghalensis e Commelina diffusa, submetidas a crescimento sob condições de sol e sombra, que pudessem influenciar a absorção e translocação deste herbicida. O complexo estomático das duas espécies é semelhante e a folha é anfiestomática. O número de estômatos na epiderme foliar foi maior em C. diffusa (38/mm² em relação a C. benghalensis (33,66/mm², na epiderme abaxial (54,86/mm² em relação à adaxial (16,80/mm² e sob sol (37,89/mm² em relação a sombra (33,77/mm². A epiderme abaxial apresentou maior número de estômatos sob sol. Pêlos secretores, do mesmo tipo, estão presentes nas duas espécies, mas em maior número em C. diffusa. Somente C. benghalensis apresentou pêlos tectores, que são de dois tipos: longos com extremidade afilada e curtos com extremidade curva; os pêlos longos concentram-se na epiderme abaxial e os pêlos curtos, na epiderme adaxial. Apesar de a presença de pêlos na epiderme foliar ser freqüentemente associada à maior absorção de herbicidas, acredita-se que o fator determinante da maior suscetibilidade de C. benghalensis ao glyphosate, em relação a C. diffusa, esteja relacionado à reserva de amido no caule. Enquanto C. benghalensis apresenta poucos e pequenos grãos de amido no parênquima medular, C. diffusa apresenta grandes e numerosos grãos de amido, o que, possivelmente, torna mais lenta a translocação simplástica de herbicidas, reduzindo a quantidade de herbicida acumulada nos pontos de crescimento e permitindo que ela rebrote mesmo após a perda total das folhas.The genus Commelina includes weed species of difficult control in several crops, chiefly when the herbicide glyphosate is used repeatedly. This work was conducted to evaluate the differences between the anatomic features of Commelina benghalensis and Commelina diffusa, grown under sun and shade conditions, which could influence herbicide absorption and translocation. The stomatal apparatus of the two species is similar and the leaf is amphistomatic. C. diffusa has a greater number of stomata in relation to C. benghalensis. The number of stomatas in the leaf epiderm is greater in C. diffusa (38/mm² than in C. benghalensis (33.66/mm², in the abaxial (54.86/mm² rather than in the adaxial epiderm (16.80/mm² and under sun (37.89/mm² rather than shade conditions (33.77/mm². The abaxial epiderm has a greater number of stomata under sun conditions. Similar secretory hair is present in both species, but in greater number in C. diffusa. Only C. benghalensis presented tector hair: (i long with slender extremity and (ii short with curved extremity. Long hair is concentrated in the abaxial epiderm and short hair in the adaxial epiderm. Although the presence of hair in the leaf epiderm is frequently associated to greater herbicide absorption, it is believed that the determinant factor of greater susceptibility of C. benghalensis to glyphosate in comparison to C. diffusa could be related to the starch stock of the stem. While C. benghalensis presents fewer and smaller starch grains in the pith parenchyma, C. diffusa presents larger and numerous starch grains, which may make herbicide simplastic translocation slower, reducing the herbicide accumulated in the growth points, and allowing it to regrowth even after total leaves loss.

  10. Caracteres anatômicos de duas espécies de trapoeraba e a eficiência do glyphosate / Anatomical features of two dayflower species (Commelina spp.) on glyphosate efficacy

    Scientific Electronic Library Online (English)

    I.C., Santos; R.M.S.A., Meira; F.A., Ferreira; L.D.T., Santos; G.V., Miranda.

    2002-04-01

    Full Text Available O gênero Commelina engloba espécies de plantas daninhas de difícil controle em diversas culturas, principalmente onde o herbicida glyphosate tem sido utilizado com elevada freqüência. Este trabalho foi conduzido com o objetivo de avaliar diferenças entre caracteres anatômicos de Commelina benghalens [...] is e Commelina diffusa, submetidas a crescimento sob condições de sol e sombra, que pudessem influenciar a absorção e translocação deste herbicida. O complexo estomático das duas espécies é semelhante e a folha é anfiestomática. O número de estômatos na epiderme foliar foi maior em C. diffusa (38/mm²) em relação a C. benghalensis (33,66/mm²), na epiderme abaxial (54,86/mm²) em relação à adaxial (16,80/mm²) e sob sol (37,89/mm²) em relação a sombra (33,77/mm²). A epiderme abaxial apresentou maior número de estômatos sob sol. Pêlos secretores, do mesmo tipo, estão presentes nas duas espécies, mas em maior número em C. diffusa. Somente C. benghalensis apresentou pêlos tectores, que são de dois tipos: longos com extremidade afilada e curtos com extremidade curva; os pêlos longos concentram-se na epiderme abaxial e os pêlos curtos, na epiderme adaxial. Apesar de a presença de pêlos na epiderme foliar ser freqüentemente associada à maior absorção de herbicidas, acredita-se que o fator determinante da maior suscetibilidade de C. benghalensis ao glyphosate, em relação a C. diffusa, esteja relacionado à reserva de amido no caule. Enquanto C. benghalensis apresenta poucos e pequenos grãos de amido no parênquima medular, C. diffusa apresenta grandes e numerosos grãos de amido, o que, possivelmente, torna mais lenta a translocação simplástica de herbicidas, reduzindo a quantidade de herbicida acumulada nos pontos de crescimento e permitindo que ela rebrote mesmo após a perda total das folhas. Abstract in english The genus Commelina includes weed species of difficult control in several crops, chiefly when the herbicide glyphosate is used repeatedly. This work was conducted to evaluate the differences between the anatomic features of Commelina benghalensis and Commelina diffusa, grown under sun and shade cond [...] itions, which could influence herbicide absorption and translocation. The stomatal apparatus of the two species is similar and the leaf is amphistomatic. C. diffusa has a greater number of stomata in relation to C. benghalensis. The number of stomatas in the leaf epiderm is greater in C. diffusa (38/mm²) than in C. benghalensis (33.66/mm²), in the abaxial (54.86/mm²) rather than in the adaxial epiderm (16.80/mm²) and under sun (37.89/mm²) rather than shade conditions (33.77/mm²). The abaxial epiderm has a greater number of stomata under sun conditions. Similar secretory hair is present in both species, but in greater number in C. diffusa. Only C. benghalensis presented tector hair: (i) long with slender extremity and (ii) short with curved extremity. Long hair is concentrated in the abaxial epiderm and short hair in the adaxial epiderm. Although the presence of hair in the leaf epiderm is frequently associated to greater herbicide absorption, it is believed that the determinant factor of greater susceptibility of C. benghalensis to glyphosate in comparison to C. diffusa could be related to the starch stock of the stem. While C. benghalensis presents fewer and smaller starch grains in the pith parenchyma, C. diffusa presents larger and numerous starch grains, which may make herbicide simplastic translocation slower, reducing the herbicide accumulated in the growth points, and allowing it to regrowth even after total leaves loss.

  11. Efficacy of Pre-Emergence and Post-Emergence Soybean Herbicides for Control of Glufosinate-, Glyphosate-, and Imidazolinone-Resistant Volunteer Corn

    OpenAIRE

    Chahal, Parminder S; Greg Kruger; Humberto Blanco-Canqui; Amit J. Jhala

    2014-01-01

    Glyphosate-resistant corn and soybean are grown in rotations in the Midwest, including Nebraska. Volunteer corn is a problematic weed in soybean fields because it causes harvest problems, reduces yield and seed quality, and potentially harbors insects, pests, and diseases. Several pre-packaged herbicides have been registered in soybean in recent years, but response of volunteer corn to these herbicides has not yet been documented. Greenhouse experiments were conducted to evaluate the respons...

  12. The intensity of non-target site mechanisms influences the level of resistance of sourgrass to glyphosate

    OpenAIRE

    Flávia Regina da Costa; Leonardo Bianco Carvalho; Pedro Luis da Costa Aguiar Alves; Rafael Prado

    2014-01-01

    Non-target site mechanisms are involved in the resistance of sourgrass (Digitaria insularis) to glyphosate. Studies on the 14C-glyphosate absorption and translocation as well as the detection of glyphosate and its metabolites in sourgrass plants were carried out under controlled conditions to investigate if the differential response of resistant sourgrass biotypes (R1 and R2) is derived from the intensity of non-target site mechanisms involved in the resistance to glyphosate. Different patter...

  13. Glifosato como desregulador endócrino químico / Glyphosate as an endocrine chemical disruptor

    Directory of Open Access Journals (Sweden)

    Renata Marino Romano

    2009-08-01

    Full Text Available ResumoDesreguladores endócrinos são moléculas exógenas ambientais que podem afetar a síntese, secreção, transporte, metabolismo, ligação, ação e catabolismo de hormônios naturais do organismo, podendo exercer seu efeito mesmo quando em mínimas quantidades. O glifosato é um herbicida utilizado no combate às plantas daninhas prejudiciais a diversas culturas, bastante efetivo, não seletivo e pós-emergente que inibe o crescimento da planta através da interferência com a produção de aminoácidos aromáticos essenciais pela inibição da fotossíntese. Em baixas concentrações não tóxicas ele causa efeito de desregulação sobre a enzima aromatase em células de placenta humana in vitro, reduzindo a atividade da enzima aromatase e reduzindo a expressão da proteína StAR (proteína de regulação rápida da esteroidogênese. Acontaminação do solo e da água tanto fluvial como subterrânea, pelo intenso uso do glifosato, pode levar a distúrbios reprodutivos, além da possibilidade da persistência de resíduos destas substâncias no sangue, na carne, no leite, na urina e nas fezes dos animais levando à recontaminação do solo e podendo chegar ao consumo humano. O objetivo desta revisão é apresentar informações atuais sobre a toxicologia do glifosato e a sua importância sobre a saúde humana, suscitando o debate nessa área, uma vez que a legislação brasileira ainda não contempla o controle desse tipo de efeito tóxico.AbstractEndocrine disruptors (EDs are exogenous molecular factors that may affect the synthesis, secretion, transport, metabolism, binding, action, and catabolism of the body’s natural hormones. They are able to produce their effect even when they are present in minimum quantities. Glyphosate is an herbicide used to combat weeds that are harmful to different plants. It is very effective, non-selective and post-emergent, inhibiting the plant growth by interfering with the production of essential aromatic amino acids for the inhibition of photosynthesis. At low and non-toxic concentrations it causes disruption effects upon the aromatase enzyme in human placenta cells in vitro, reducing the activity of this enzyme and reducing the expression of the StAR protein (steroid acute regulatory protein. The contamination of soil and of both surface and underground water due to the intense use of glyphosate may lead to reproductive disorders and also the possibility of the persistence of residues of these substances in blood, meat, milk, urine and animal excrements, leading to the recontamination of the soil and possibly reaching products consumed by humans. The purpose of this review has been to provide current information on the toxicology of glyphosate (formulation Roundup and its importance for human health, raising the debate in this field, since the Brazilian legislation does not address the control of such toxic effects yet.

  14. Re-evaluation of groundwater monitoring data for glyphosate and bentazone by taking detection limits into account.

    Science.gov (United States)

    Hansen, Claus Toni; Ritz, Christian; Gerhard, Daniel; Jensen, Jens Erik; Streibig, Jens Carl

    2015-12-01

    Current regulatory assessment of pesticide contamination of Danish groundwater is exclusively based on samples with pesticide concentrations above detection limit. Here we demonstrate that a realistic quantification of pesticide contamination requires the inclusion of "non-detect" samples i.e. samples with concentrations below the detection limit, as left-censored observations. The median calculated pesticide concentrations are shown to be reduced 10(4) to 10(5) fold for two representative herbicides (glyphosate and bentazone) relative to the median concentrations based upon observations above detection limits alone. PMID:26196070

  15. Re-evaluation of groundwater monitoring data for glyphosate and bentazone by taking detection limits into account

    DEFF Research Database (Denmark)

    Hansen, Claus Toni; Ritz, Christian

    2015-01-01

    Current regulatory assessment of pesticide contamination of Danish groundwater is exclusively based on samples with pesticide concentrations above detection limit. Here we demonstrate that a realistic quantification of pesticide contamination requires the inclusion of "non-detect" samples i.e. samples with concentrations below the detection limit, as left-censored observations. The median calculated pesticide concentrations are shown to be reduced 10(4) to 10(5) fold for two representative herbicides (glyphosate and bentazone) relative to the median concentrations based upon observations above detection limits alone.

  16. Intercropping frost-sensitive legume crops with winter oilseed rape reduces weed competition, insect damage, and improves nitrogen use efficiency

    Directory of Open Access Journals (Sweden)

    Cadoux Stéphane

    2015-05-01

    Full Text Available Mixing plant species in agroecosystems is highlighted as an agroecological solution to reduce pesticides and fertilizers while maintaining profitability. In the French context, intercropping frost-sensitive legume crops with winter oilseed rape is potentially interesting and began to be implemented by farmers. In this study we aimed at measuring the services and disservices of this intercrop with three different legume mixtures, in terms of growth and yield for rapeseed, ground cover of weeds in autumn and damage caused by rape winter stem weevil. The experiment was carried out at four sites from 2011 to 2014. We showed higher total aerial dry weights and total aerial nitrogen contents in the intercrops compared to sole winter oilseed rape in November. The companion plants contributed to the control of weeds and the mitigation of rape winter stem weevil damage, notably through the increase in the total aerial weight. In spring, after destruction of the companion plants, the intercrops had partially compensated a reduction in the N fertilization rate (–30 kg per hectare in terms of aerial nitrogen content in rapeseed, with no consequences on the yield which was maintained or even increased. There were probably other interactions such as an improvement in rapeseed root exploration. The consequences were an increase in the nitrogen use efficiency in intercrops. The intercrop with faba bean and lentil showed the best results in terms of autumn growth, weed control, reduction in rape winter stem weevil damage, and rapeseed N content in spring and yield. Intercropping frost-sensitive legume crops with winter oilseed rape is thus a promising way to reconcile yield and reduction in pesticides and fertilizer use and perhaps to benefit more widely to the cropping system.

  17. Efeito de adjuvantes adicionados à calda herbicida contendo glyphosate / Effect of adjuvants added to herbicide spray containing glyphosate

    Scientific Electronic Library Online (English)

    Leandro, Vargas; Nilson G., Fleck; Marcos M. da, Cunha; Ribas A., Vidal.

    Full Text Available Tentativas de aumentar a fitotoxicidade do herbicida glyphosate através da adição de ácido e/ ou de sulfato de amônio à calda tem sido promissoras. A adição dessas substâncias otimiza as propriedades químicas da calda herbicida, superando efeitos negativos do pH elevado e de ions nela presentes. O o [...] bjetivo desse trabalho foi investigar o efeito da adição de ácido sulfúrico e/ou de sulfato de amônio à calda herbicida, sobre a eficiência do glyphosate misturado em diluente com alto pH e teores elevados de sais. Os tratamentos envolveram cinco doses de glyphosate (variáveis de 180 a 540 g/ha i.a.) diluídas em água destilada e, mais glyphosate a 270 g/ha misturado às águas minera is Fonte Azul e Fonte Ijuí em presença de ácido sulfúrico (0,5 1/ha) e/ou sulfato de amônio (2 ,5 kg/h a) . A fitotoxicidade foi avaliada aos 7, 17 e 27 dias após as aplicações do herbicida sobre a aveia preta. Os resultados demonstraram que a aveia-preta é muito suscetível à ação de glyphosate, mesmo aplicado a 270 g/ha, independente da água utilizada ou da adição de adjuvantes e, que a adição de ácido sulfúrico e/ou de sulfato de amônio à calda não alterou a atividade do herbicida. Abstract in english Attempts to increase phytotoxicity of glyphosat e her bic ide through addition of acid and/or of ammonium sulphate to the spray solution have been promising. Addition of these substances optimize chemical properties of the herbicide spray, overcoming negative effects of high pH and of íons present i [...] n it. The objective of this research was to investigate the effect of sulphuric acid and/or of ammonium sulphate addition to herbicide spray, on the efficiency of glyphosate mixed in diluents with high pH and high salts content. Glyphosate treatments consisted of five rates (variables from 180 to 540 g/ha a.e.), diluted in distilled water, and also glyph osate at 270 g/h a a. e. mix ed in the mineral waters Fonte Azul and Fonte Ijuí. To this herbicide rate, it was added 0,5 1/ha of sulphuric acid and /or 2,5 kg/ha of ammonium sulphate, whose treatments were sprayed over oat plants. Herbicide toxicity was evaluated at 7, 17, and 27 days after applications. Results showed that oats was very susceptible to glyphosate action, even when applied at 270 g/ha, independent of water used or adjuvantes added. It is concluded that addition of sulphuric acid and/or of ammonium sulphate to spray solution do not increase herbicide activity of glyphosate.

  18. Efeito de adjuvantes adicionados à calda herbicida contendo glyphosate Effect of adjuvants added to herbicide spray containing glyphosate

    Directory of Open Access Journals (Sweden)

    Leandro Vargas

    1997-01-01

    Full Text Available Tentativas de aumentar a fitotoxicidade do herbicida glyphosate através da adição de ácido e/ ou de sulfato de amônio à calda tem sido promissoras. A adição dessas substâncias otimiza as propriedades químicas da calda herbicida, superando efeitos negativos do pH elevado e de ions nela presentes. O objetivo desse trabalho foi investigar o efeito da adição de ácido sulfúrico e/ou de sulfato de amônio à calda herbicida, sobre a eficiência do glyphosate misturado em diluente com alto pH e teores elevados de sais. Os tratamentos envolveram cinco doses de glyphosate (variáveis de 180 a 540 g/ha i.a. diluídas em água destilada e, mais glyphosate a 270 g/ha misturado às águas minera is Fonte Azul e Fonte Ijuí em presença de ácido sulfúrico (0,5 1/ha e/ou sulfato de amônio (2 ,5 kg/h a . A fitotoxicidade foi avaliada aos 7, 17 e 27 dias após as aplicações do herbicida sobre a aveia preta. Os resultados demonstraram que a aveia-preta é muito suscetível à ação de glyphosate, mesmo aplicado a 270 g/ha, independente da água utilizada ou da adição de adjuvantes e, que a adição de ácido sulfúrico e/ou de sulfato de amônio à calda não alterou a atividade do herbicida.Attempts to increase phytotoxicity of glyphosat e her bic ide through addition of acid and/or of ammonium sulphate to the spray solution have been promising. Addition of these substances optimize chemical properties of the herbicide spray, overcoming negative effects of high pH and of íons present in it. The objective of this research was to investigate the effect of sulphuric acid and/or of ammonium sulphate addition to herbicide spray, on the efficiency of glyphosate mixed in diluents with high pH and high salts content. Glyphosate treatments consisted of five rates (variables from 180 to 540 g/ha a.e., diluted in distilled water, and also glyph osate at 270 g/h a a. e. mix ed in the mineral waters Fonte Azul and Fonte Ijuí. To this herbicide rate, it was added 0,5 1/ha of sulphuric acid and /or 2,5 kg/ha of ammonium sulphate, whose treatments were sprayed over oat plants. Herbicide toxicity was evaluated at 7, 17, and 27 days after applications. Results showed that oats was very susceptible to glyphosate action, even when applied at 270 g/ha, independent of water used or adjuvantes added. It is concluded that addition of sulphuric acid and/or of ammonium sulphate to spray solution do not increase herbicide activity of glyphosate.

  19. Effect of formulations on the absorption and translocation of glyphosate in transgenic soybean; Efeito de formulacoes na absorcao e translocacao do glyphosate em soja transgenica

    Energy Technology Data Exchange (ETDEWEB)

    Santos, J.B. [UNIVALE, Governador Valadares, MG (Brazil). FAAG. Agronomia]. E-mail: jbarbosa@univale.br; Ferreira, E.A.; Silva, A.A. [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Fitotecnia]. E-mail: evanderalves@yahoo.com.br; aasilva@ufv.br; Oliveira, J.A. [Universidade Federal de Vicosa (UFV), MG (Brazil). Dept. de Biologia Geral]. E-mail: jalves@ufv.br; Fialho, C.M.T. [Universidade Federal de Vicosa (UFV), MG (Brazil). Agronomia]. E-mail: cintiamtfialho@yahoo.com.br

    2007-07-01

    This study was carried out to evaluate the absorption and translocation of glyphosate formulations in genetically modified (GM) soybean by applying 14C-glyphosate mixed to three glyphosate formulations (Roundup Ready and R. Transorb - both with +isopropylamine salt, and Zapp Qi, formulated from potassic salt ), using a precision micro syringe. Plant samples were collected after herbicide application (4, 16, 40 and 64 hours) and then divided into leaf (trifolium), aerial part, roots and root nodes for radiation reading. 14C-glyphosate that was not absorbed was recovered and counted by washing the leaf with methanol. Penetration and translocation of 14C-glyphosate to the different parts evaluated was found to vary. However, the highest absorption was verified at intervals after 16 hours of application. The highest herbicide percentage in the aerial part of the soybean plants was found when Zapp (potassic salt) was applied on the aerial part and when isopropylamin salt was applied on the roots; 14C-glyphosate was found in the plant root nodules in all treatments, with the highest percentage being observed with R. Transorb, 40 hours after application (0.13% of the total measured or 0.4%, considering only the plant total). Results highlight the hypothesis that glyphosate could harm symbiosis between rhizobium and soybean, since the former also shows in its metabolism EPSPS, which is susceptible to this herbicide. (author)

  20. 40 CFR 174.524 - Glyphosate Oxidoreductase GOX or GOXv247 in all plants; exemption from the requirement of a...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Glyphosate Oxidoreductase GOX or... REQUIREMENTS FOR PLANT-INCORPORATED PROTECTANTS Tolerances and Tolerance Exemptions § 174.524 Glyphosate... Glyphosate Oxidoreductase GOX or GOXv247 enzyme in all plants are exempt from the requirement of a...

  1. Consequences of phosphate application on glyphosate uptake by roots: Impacts for environmental management practices.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; Maccario, Sophie; Lucotte, Marc; Labrecque, Michel; Juneau, Philippe

    2015-12-15

    Phosphate (PO4(3-)) fertilization is a common practice in agricultural fields also targets for glyphosate application. Due to their chemical similarities, PO4(3-) and glyphosate compete for soil adsorbing sites, with PO4(3-) fertilization increasing glyphosate bioavailability in the soil solution. After PO4(3-) fertilization, its concentration will be elevated in the soil solution and both PO4(3-) and glyphosate will be readily available for runoff into aquatic ecosystems. In this context, man-made riparian buffer strips (RBS) at the interface of agricultural lands and waterways can be used as a green technology to mitigate water contamination. The plants used in RBS form a barrier to agricultural wastes that can limit runoff, and the ability of these plants to take up these compounds through their roots plays an important role in RBS efficacy. However, the implications of PO4(3-) for glyphosate uptake by roots are not yet clearly demonstrated. Here, we addressed this problem by hydroponically cultivating willow plants in nutrient solutions amended with glyphosate and different concentrations of PO4(3-), assuring full availability of both chemicals to the roots. Using a phosphate carrier inhibitor (phosphonophormic acid-PFA), we found that part of the glyphosate uptake is mediated by PO4(3-) transporters. We observed, however, that PO4(3-) increased glyphosate uptake by roots, an effect that was related to increased root cell membrane stability. Our results indicate that PO4(3-) has an important role in glyphosate physiological effects. Under agricultural conditions, PO4(3-) fertilization can amplify glyphosate efficiency by increasing its uptake by the roots of undesired plants. On the other hand, since simultaneous phosphate and glyphosate runoffs are common, non-target species found near agricultural fields can be affected. PMID:26282745

  2. Research on the weed control degree and glyphosate soil biodegradation in apple plantations (Pioneer variety

    Directory of Open Access Journals (Sweden)

    Ersilia ALEXA

    2010-05-01

    Full Text Available In this study we follow control degree of glyphosate herbicide on weeds in apple plantations (Pioneer variety of the Research Station Timisoara. It was also followed glyphosate biodegradation capacity in the soil by determining the amount of CO2 released by the action of microorganisms on C14 glyphosate marked isotope. Laboratory analysis of glyphosate residues in soil was made using a Liquid Scintillation TRIATHLER. Glyphosate biodegradation ability in the presence of soil microorganisms is high, so glyphosate residues remaining in soil, in terms of its use in weed combating, are minimal. Study of glyphosate biodegradation capacity in the experimental field indicates that the CO2 fraction accumulated after 50 days is 28.02% for samples exposed in the experimental field. Weather conditions, especially temperature variations between day and night, influences the activity of soilmicroorganisms and affect biodegraded glyphosate percentage.Chemical method of weed control consisted in: herbicide used was Roundup 3 l/ha (glyphosate isopropyl amine salt 360 g/l and are based on chemical application on weeds, on the rows of trees, on their uptake and translocation in their organs having as principal scope the total destruction of weeds. The experimental results obtained reveal a weed combat degree of 82.98% , in the case of chemical variant, compared with control variant. The species combated mainly due to glyphosate herbicide, which is no longer found in the final mapping are: Capsella bursa-pastoris, Chenopodium album, Echinochloa crus-galli, Plantago major, Polygonum aviculare. Total combated weeds /m2 with glyphosate is 126.67.

  3. Rhamnolipids elicit the same cytotoxic sensitivity between cancer cell and normal cell by reducing surface tension of culture medium.

    Science.gov (United States)

    Jiang, Lifang; Shen, Chong; Long, Xuwei; Zhang, Guoliang; Meng, Qin

    2014-12-01

    Biosurfactant rhamnolipids have been claimed to show biological activities of inhibiting the proliferation of cancer cells. In this study, the cytotoxicity of rhamnolipids was examined on four cancer cells (HepG2, Caco-2, Hela, MCF-7 cells) and two normal cells (HK-2 cell, primary hepatocyte). Interestingly, both cancer cells and normal cells exhibited similar sensitivities to the addition of rhamnolipids in culture medium, and the cytotoxicity was largely attenuated by the presence of fetal bovine serum (FBS) in culture medium. In correlation of the mono-/di-rhamnolipid cytotoxicity with the surface tension of culture medium, it was found that rhamnolipids triggered cytotoxicity whenever the surface tension of culture medium decreased below 41 mN/m irrespective of the FBS content in culture medium, cell line, or rhamnolipid congener. Similarly, each chemical surfactant (Tween-80, sodium dodecyl sulfate, and sodium dodecyl benzene sulfonate) could cause cytotoxicity on HepG2 cells whenever its addition made the surface tension under 41 mN/m in culture medium with or without the presence of FBS. It seems that rhamnolipids, like chemical surfactants, exhibited cytotoxicity by reducing the surface tension of culture medium rather than by changing its specific molecular structure, which had no selection on tumor cells. This study could offer helps to correct the misleading biological activity of rhamnolipids and to avoid the possible large wastes of time and expenses on developing the applications in antitumor drugs. PMID:25231070

  4. Fast and Sensitive Detection of Pb2+ in Foods Using Disposable Screen-Printed Electrode Modified by Reduced Graphene Oxide

    Directory of Open Access Journals (Sweden)

    Qiang Cai

    2013-09-01

    Full Text Available In this study, reduced graphene oxide (rGO was electrochemically deposited on the surface of screen-printed carbon electrodes (SPCE to prepare a disposable sensor for fast detection of Pb2+ in foods. The SEM images showed that the rGO was homogeneously deposited onto the electrode surface with a wrinkled nanostructure, which provided 2D bridges for electron transport and a larger active area for Pb2+ adsorption. Results showed that rGO modification enhanced the activity of the electrode surface, and significantly improved the electrochemical properties of SPCE. The rGO modified SPCE (rGO-SPCE was applied to detect Pb2+ in standard aqueous solution, showing a sharp stripping peak and a relatively constant peak potential in square wave anodic stripping voltammetry (SWASV. The linear range for Pb2+ detection was 5~200 ppb (R2 = 0.9923 with a low detection limit of 1 ppb (S/N = 3. The interference of Cd2+ and Cu2+ at low concentrations was effectively avoided. Finally, the rGO-SPCE was used for determination of lead in real tap water, juice, preserved eggs and tea samples. Compared with results from graphite furnace atomic absorption spectroscopy (GFAAS, the results based on rGO-SPCE were both accurate and reliable, suggesting that the disposable sensor has great potential in application for fast, sensitive and low-cost detection of Pb2+ in foods.

  5. Identificação de biótipos de azevém (Lolium multiflorum) resistentes ao herbicida glyphosate em pomares de maçã Identification of glyphosate-resistant ryegrass (Lolium multiflorum) biotypes in apple orchards

    OpenAIRE

    L. VARGAS; E.S. Roman; M.A Rizzardi; V.C. Silva

    2004-01-01

    O glyphosate é um herbicida de amplo espectro utilizado há mais de 15 anos em pomares de maçã na região de Vacaria-RS, para manejo da vegetação nas linhas da cultura. São realizadas, em geral, três a quatro aplicações por ciclo e a dose normalmente utilizada é de 720 a 1.080 g e.a. ha-1 de glyphosate (2 a 3 L ha-1 do produto comercial). O azevém (Lolium multiflorum) é uma planta daninha comum em pomares e, tradicionalmente, sensível ao glyphosate. Entretanto, nos últimos anos a ocorrência de ...

  6. Seletividade de glyphosate isolado ou em misturas para soja RR em aplicações sequenciais Selectivity of glyphosate alone or in mixtures for RR soybean in sequential applications

    OpenAIRE

    D.G. Alonso; J. Constantin; R.S. Oliveira JR; Santos, G.; H.A Dan; A.M. Oliveira Neto

    2013-01-01

    O uso de misturas de herbicidas latifolicidas com o glyphosate tem sido uma alternativa para o controle de plantas daninhas resistentes ao glyphosate ou de difícil controle nos cultivos de soja RR. Este trabalho teve o objetivo de avaliar a seletividade de aplicações sequenciais de glyphosate, isolado ou em mistura com latifolicidas, para a soja RR. As aplicações dos tratamentos foram feitas em plantas de soja cultivar CD214 RR nos estádios de desenvolvimento V1 a V2 e V3 a V4. Os herbicidas ...

  7. Absorção, translocação e metabolismo do glyphosate por plantas tolerantes e suscetíveis a este herbicida Absorption, translocation and metabolism of glyphosate by plants tolerant and susceptible to this herbicide

    OpenAIRE

    P.A Monquero; P.J. Christoffoleti; M.D. Osuna; R.A. De Prado

    2004-01-01

    O objetivo deste trabalho foi caracterizar a absorção foliar, a translocação e o metabolismo do 14C-glyphosate pelas plantas daninhas Commelina benghalensis, Ipomoea grandifolia e Amaranthus hybridus. O glyphosate foi aplicado através de quatro gotas de 0,5 µL de uma solução contendo o produto comercial, na dose de campo de 720 g e.a. ha-1 em mistura com 14C-glyphosate, na face adaxial da segunda folha verdadeira das plantas estudadas. As avaliações foram feitas a 2, 4, 8, 12, 24, 48 e ...

  8. Ecotoxicological assessment of soil microbial community tolerance to glyphosate.

    Science.gov (United States)

    Allegrini, Marco; Zabaloy, María Celina; Gómez, Elena del V

    2015-11-15

    Glyphosate is the most used herbicide worldwide. While contrasting results have been observed related with its impact on soil microbial communities, more studies are necessary to elucidate the potential effects of the herbicide. Differences in tolerance detected by Pollution Induced Community Tolerance (PICT) approach could reflect these effects. The objective of the present study was to assess the tolerance to glyphosate (the active ingredient and a commercial formulation) of contrasting soils with (H) and without (NH) history of exposure. The hypothesis of a higher tolerance in H soils due to a sustained selection pressure on community structure was tested through the PICT approach. Results indicated that tolerance to glyphosate is not consistent with previous history of exposure to the herbicide either for the active ingredient or for a commercial formulation. Soils of H and NH sites were also characterized in order to determine to what extent they differ in their functional diversity and structure of microbial communities. Denaturant Gradient Gel Electrophoresis (DGGE) and Quantitative Real Time PCR (Q-PCR) indicated high similarity of Eubacteria profiles as well as no significant differences in abundance, respectively, between H and NH sites. Community level physiological profiling (CLPP) indicated some differences in respiration of specific sources but functional diversity was very similar as reflected by catabolic evenness (E). These results support PICT assay, which ideally requires soils with differences in their exposure to the contaminant but minor differences in other characteristics. This is, to our knowledge, the first report of PICT approach with glyphosate examining tolerance at soil microbial community level. PMID:26150308

  9. Genotoxicity of diuron and glyphosate in oyster spermatozoa and embryos

    OpenAIRE

    Akcha, Farida; Spagnol, Charlene; Rouxel, Julien

    2012-01-01

    We investigated the effects of genotoxicant exposure in gametes and embryos to find a possible link between genotoxicity and reproduction/developmental impairment, and explore the impact of chemical genotoxicity on population dynamics. Our study focused on the genotoxic effects of two herbicides on oyster gametes and embryos: glyphosate (both as an active substance and in the Roundup formulation) and diuron. France is Europe's leading consumer of agrochemical substances and as such, contamina...

  10. Shikimate accumulation, glyphosate absorption and translocation in horseweed biotypes / Acúmulo de chiquimato, absorção e translocação do glyphosate em biótipos de buva

    Scientific Electronic Library Online (English)

    V.C.B., CARDINALI; A.C.R., DIAS; T.C., MUELLER; L., ABERCROMBIE; C.N., STEWART JR.; V.L., TORNISIELO; P.J., CHRISTOFFOLETI.

    2015-03-01

    Full Text Available No Brasil, poucos trabalhos de pesquisas com mecanismos de resistência de plantas daninhas ao glyphosate foram conduzidos até o momento. Assim, o objetivo desta pesquisa foi estudar procedimentos analíticos para determinar a relação da concentração de chiquimato na planta após aplicação de glyphosat [...] e e a resistência da planta a este herbicida, bem como avaliar a absorção e translocação do herbicida glyphosate em dois biótipos de buva, resistente ® e suscetível (S) ao glyphosate. Plantas de buva com nove folhas definitivas receberam glyphosate (720 g e.a. ha-1), e 2, 3, 4, 7 e 10 dias após a aplicação (DAA) foi medida a concentração de ácido chiquímico da parte aérea, através de HPLC. Em outro experimento, as plantas foram tratadas com glyphosate radiomarcado (14C) (atividade específica de 1,456 MBq mmol-1), e a radioatividade foi determinada 4, 8, 24, 48 e 72 horas após o tratamento (HAT), por espectrometria de cintilação líquida. A concentração de chiquimato aumentou (16.351,14 e 7.892,25 mg kg-1 de matéria seca nas plantas R e S, respectivamente) aos 7 DAA. Portanto, o procedimento de quantificação do ácido chiquímico foi adequado para diferenciação das plantas R e S ao glyphosate, indicando que a população R estudada é resistente ao glyphosate. Em média, 98% do glyphosate aplicado foi absorvido pelos biótipos estudados 72 HAT. Cerca de 68% da radioatividade absorvida permaneceu nas folhas tratadas dos biótipos, sendo que o biótipo S foi o que mais translocou. Assim, o mecanismo de resistência no biótipo R estudado está relacionado com a translocação diferencial. Abstract in english In Brazil, few research works on mechanisms of weed resistance to glyphosate have been conducted so far. Therefore, this research aimed to study analytical procedures determining the relation between the concentration of plant shikimate after glyphosate application and the plant resistance to this h [...] erbicide; and evaluate the glyphosate absorption and translocation into two resistant ® and susceptible (S) horseweed biotypes to glyphosate. Horseweed plants with nine true leaves received glyphosate (720 g a.e. ha-1), and 2, 3, 4, 7 and 10 days after application (DAA) the concentration of shikimic acid was measured by HPLC. In another experiment, plants were treated with radiolabeled glyphosate (14C) (1.456 MBq mmol-1 specific activity) and radioactivity was measured 4, 8, 24, 48 and 72 hours after treatment (HAT) by liquid scintillation spectrometry. The shikimate concentration in plants increased 16,351.14 and 7,892.25 mg kg-1 of dry weight, for R and S plants respectively, at seven DAA. Therefore, the procedure for quantification of shikimic acid was suitable for R and S plants differentiation to glyphosate, indicating that the R population is actually resistant to glyphosate. On average, 98% of glyphosate applied was absorbed by the studied biotypes, at 72 HAT. Around 68% of the absorbed radioactivity remained on the biotypes leaves treated, the S biotype showing the highest translocation. Therefore, the R biotype resistance mechanism studied is associated to the differential translocation.

  11. Association effects of glyphosate and phosphite in maize plants

    Directory of Open Access Journals (Sweden)

    Giovanna Larissa Gimenes Cotrick Gomes

    2013-04-01

    Full Text Available The objective of this study was to evaluate the effects of glyphosate herbicide association with potassium phosphite in maize plants. The experiment was accomplished in green house conditions, with seeding of Pioneer 30F53H simple hybrid in vases. Experimental design used was entirely randomized with six treatments and four replications. Treatments application was made with plants in V7 developmental stage. Evaluations of electron transport rate (ETR in photo system II were conducted during periods of 1, 2, 5, 32, 56, 80, 104, 128, 152, 176, 200 and 360 hours after application (HAA, as well as visual determinations of intoxication in the same plants at 2, 4, 6, 10 and 15 days after application (DAA. At the end of experiment (15 DAA it was determined plants height with a graduated ruler from soil level as far as the insertion of last leaf fully expanded, and leaves and stalks dry mass. Glyphosate association with potassium phosphite Fosway® (3.0 L ha-1, with 30% of P2O5 and 20% of K2O with 72 g a.e. ha-1 dose increased the levels of plant intoxication. Maize plants submitted to 72 g a.e. ha-1 dose alone showed higher growth than control. ETR of treated plants showed an increase in the first hours after application, and subsequent reduction in plants exposed to higher doses of glyphosate associated or not with potassium phosphite.

  12. Glyphosate carryover in seed potato: effects on mother crop and daughter tubers

    Science.gov (United States)

    Field studies were conducted in 2008 and 2009 in Aberdeen, ID, Ontario, OR, and Paterson, WA to determine the effect of simulated glyphosate drift on ‘Ranger Russet’ potato during the application year and the crop growing the next year from the daughter tubers. Glyphosate was applied at 8.5, 54, 107...

  13. Early detection of crop injury from herbicide glyphosate by leaf biochemical parameter inversion

    Science.gov (United States)

    Zhao, Feng; Guo, Yiqing; Huang, Yanbo; Reddy, Krishna N.; Lee, Matthew A.; Fletcher, Reginald S.; Thomson, Steven J.

    2014-09-01

    Early detection of crop injury from herbicide glyphosate is of significant importance in crop management. In this paper, we attempt to detect glyphosate-induced crop injury by PROSPECT (leaf optical PROperty SPECTra model) inversion through leaf hyperspectral reflectance measurements for non-Glyphosate-Resistant (non-GR) soybean and non-GR cotton leaves. The PROSPECT model was inverted to retrieve chlorophyll content (Ca+b), equivalent water thickness (Cw), and leaf mass per area (Cm) from leaf hyperspectral reflectance spectra. The leaf stress conditions were then evaluated by examining the temporal variations of these biochemical constituents after glyphosate treatment. The approach was validated with greenhouse-measured datasets. Results indicated that the leaf injury caused by glyphosate treatments could be detected shortly after the spraying for both soybean and cotton by PROSPECT inversion, with Ca+b of the leaves treated with high dose solution decreasing more rapidly compared with leaves left untreated, whereas the Cw and Cm showed no obvious difference between treated and untreated leaves. For both non-GR soybean and non-GR cotton, the retrieved Ca+b values of the glyphosate treated plants from leaf hyperspectral data could be distinguished from that of the untreated plants within 48 h after the treatment, which could be employed as a useful indicator for glyphosate injury detection. These findings demonstrate the feasibility of applying the PROSPECT inversion technique for the early detection of leaf injury from glyphosate and its potential for agricultural plant status monitoring.

  14. Selection and physiological response of glyphosate resistant zoysiagrass mutants derived from a radiation breeding technique

    International Nuclear Information System (INIS)

    This study was conducted to select of zoysiagrass mutants resistant to glyphosate and to identify their physiological and molecular characteristics. Experiments were conducted to determine the effects of glyphosate on the physiological responses in zoysiagrass and to select mutants resistant to glyphosate. The results indicated that the optimum concentration for a mutant resistant to glyphosate selection is 0.5?1.0%. In order to select mutants resistant to glyphosate, M2 plants were sprayed with 0.5% glyphosate after propagation. M2 seeds were collected from the plants that survived after being irradiated with 300Gy gamma ray. Three resistant and susceptible M2 plants were selected for an analysis of their physiological characters. The electrolyte leakage was increased more in the susceptible plants than the resistant plants treated with 0.5% glyphosate. A difference in the malondialdehyde content was not evident between the resistant and susceptible plants. The chlorophyll and carotenoid contents were decreased in the plants treated with 0.5% glyphosate with a greater reduction in the susceptible plants than in the resistant plants. And, the zoysiagrass 5-enolpyruvyl-shikimate-3-phosphate synthase gene was cloned by RT-PCR and RACE (Rapid Amplification of cDNA Ends) approaches. The derived cDNA sequence revealed a high homology with the genes reported in other species. (author)

  15. Assessing the risk of Glyphosate to native plants and weedy Brassicaceae species of North Dakota

    Science.gov (United States)

    This study was conducted to determine the ecological risk to native plants and weedy Brassicaceae species which may be growing in areas affected by off target movement of glyphosate applied to glyphosate-resistant canola (Brassica napus). Ten native grass and forb species were ...

  16. Seasonal timing of glyphosate ripener application affects sugarcane’s response in Louisiana

    Science.gov (United States)

    Glyphosate is applied as a ripener to ratoon sugarcane in Louisiana to increase theoretically recoverable sugar (TRS) in harvested sugarcane. While glyphosate is applied as a ripener throughout the harvest season, recommendations for these applications have been based primarily on the response of s...

  17. Biodegradation of glyphosate herbicide by Salinicoccus spp isolated from Qom Hoze-soltan lake, Iran

    Directory of Open Access Journals (Sweden)

    Yaser Sharifi

    2015-01-01

    Full Text Available Background: Glyphosate (N-phosphonomethyl Glycine is an organophosphorus pesticide with dangerous effects on the environment. In this study, the biodegradation of glyphosate herbicide by halophilic bacteria isolated from Qom Hoze-Soltan Lake has been investigated. Methods: After sampling and bacterial isolation, native halophilic strains grown in the presence of glyphosate at a wavelength of 660 nm and also the disappearance of the glyphosate in the plates at a wavelength of 220 nm were determined and the dominant bacteria were isolated. Biochemical, molecular (according to the 16S rRNA sequence, antibiotic, and the Minimum Inhibitory Concentration (MIC test was performed for the dominant bacteria. Analysis of the remaining glyphosate herbicide was performed by HPLC analysis after derivation with FMOC-Cl. Results: According to the results of the biochemical, antibiotic and molecular 16S rRNA tests, the native halophilic isolates with the ability to biodegrade glyphosate were gram positive cocci very similar to Salinicoccusspp. The results of HPLC showed that Salinicoccusspp is able to biodegrade glyphosate herbicide. Conclusion: The native bacteria in Qom Hoze-soltanlake, Iran can be used for biodegradation of glyphosate herbicide.

  18. Effects of glyphosate application timing and rate on sicklepod (Senna obtusifolia) fecundity

    Science.gov (United States)

    Greenhouse experiments were conducted to examine the effect of glyphosate on reproductive development in sicklepod. Glyphosate was applied postemergence over the top at 112 and 280 g ai/ha to sicklepod at 4-leaf stage (L), 8-L, 4-L followed by 8-L, and 12-L. A nontreated control was included. Immedi...

  19. Response of Pennsylvania native plant species to dicamba and/or glyphosate

    Science.gov (United States)

    Weeds may become resistant to intensive and extensive use of specific herbicides associated with the growth of herbicide tolerant crops, e.g., the use of glyphosate for weed control with glyphosate tolerant soybeans. To counter this resistance, crops modified to contain genes for...

  20. Correlation of leaf damage with uptake and translocation of glyphosate in velvetleaf (Abutilon theophrasti)

    International Nuclear Information System (INIS)

    Uptake and translocation of glyphosate in three commercial formulations were examined in velvetleaf, a dicotyledonous weed that is commonly treated with glyphosate. The formulations included Roundup(R) (MON35085), Roundup Ultra, and Touchdown(R) as sold in Canada. A minimal amount of 14C-glyphosate was spiked into a lethal rate of each formulation, and the short-term (3 to 72 h) uptake into the treated leaf and subsequent translocation into the plant were measured. Time-course studies showed very rapid uptake and translocation of glyphosate in the Ultra formulation. In comparison, the uptake and translocation of glyphosate in Touchdown was much slower but continued throughout the 72-h period. Glyphosate in the Roundup formulation showed intermediate uptake and translocation. Tissue necrosis at the application sites of Ultra and Roundup was visible within 24 h after treatment. Examinations using stereo and fluorescence microscopy revealed extensive cell death and tissue disruption. Tissue necrosis from Ultra and Roundup was also observed in blank formulations containing no glyphosate and therefore was likely caused by the surfactants. In contrast, the application sites of Touchdown produced little to no leaf damage. Our results demonstrated a direct correlation between tissue necrosis and rapid rates of glyphosate uptake and translocation. (author)

  1. An Interlaboratory Comparative Study on the Quantitative Determination of Glyphosate at Low Levels in Wheat Flour.

    Science.gov (United States)

    Simonetti, Emanuela; Cartaud, Gérald; Quinn, Robert M; Marotti, Ilaria; Dinelli, Giovanni

    2015-12-01

    In recent years, the use of glyphosate has dramatically increased worldwide, and there is growing concern about contamination of organic products caused by its heavy use on neighboring fields. Glyphosate is found as a residue not only in soil, plants, and groundwater but also in humans and animals. Considering the controversy on glyphosate maximum residue level in foodstuff and the difficulties in its analytical determination, the main purpose of the present paper was to investigate the competence and accuracy of 13 accredited European laboratories in determining glyphosate in wheat flour at a level close to their reporting limit of 10 ?g/kg. According to the results of this performance assessment, the laboratories were not able to quantify glyphosate at trace levels. Therefore, their specified reporting limits of 10 ?g/kg were not supported by their results, and a reporting limit of around 50 ?g/kg of glyphosate in flour seems to be more appropriate to guarantee reliable and robust results. The widespread use of glyphosate and its harmfulness to humans make its detection at trace levels a primary goal for analytical laboratories. This is achievable through the improvement of QA and/or the optimization of the method of analysis used for glyphosate detection. PMID:26651590

  2. Bioassay and characterization of several palmer amaranth biotypes with varying tolerances to glyphosate

    Science.gov (United States)

    The wide distribution of Palmer amaranth in the southern U.S. became a serious weed control problem prior to the extensive use of glyphosate-resistant crops. Currently glyphosate-resistant populations of Palmer amaranth occur in many areas of this geographic region creating an even more serious thr...

  3. Men who have sex with men sensitivity training reduces homoprejudice and increases knowledge among Kenyan healthcare providers in coastal Kenya

    Directory of Open Access Journals (Sweden)

    Elise M van der Elst

    2013-12-01

    Full Text Available Introduction: Healthcare workers (HCWs in Africa typically receive little or no training in the healthcare needs of men who have sex with men (MSM, limiting the effectiveness and reach of population-based HIV control measures among this group. We assessed the effect of a web-based, self-directed sensitivity training on MSM for HCWs (www.marps-africa.org, combined with facilitated group discussions on knowledge and homophobic attitudes among HCWs in four districts of coastal Kenya. Methods: We trained four district “AIDS coordinators” to provide a two-day training to local HCWs working at antiretroviral therapy-providing facilities in coastal Kenya. Self-directed learning supported by group discussions focused on MSM sexual risk practices, HIV prevention and healthcare needs. Knowledge was assessed prior to training, immediately after training and three months after training. The Homophobia Scale assessed homophobic attitudes and was measured before and three months after training. Results: Seventy-four HCWs (68% female; 74% clinical officers or nurses; 84% working in government facilities from 49 health facilities were trained, of whom 71 (96% completed all measures. At baseline, few HCWs reported any prior training on MSM anal sexual practices, and most HCWs had limited knowledge of MSM sexual health needs. Homophobic attitudes were most pronounced among HCWs who were male, under 30 years of age, and working in clinical roles or government facilities. Three months after training, more HCWs had adequate knowledge compared to baseline (49% vs. 13%, McNemar's test p<0.001; this was most pronounced in those with clinical or administrative roles and in those from governmental health providers. Compared to baseline, homophobic attitudes had decreased significantly three months after training, particularly among HCWs with high homophobia scores at baseline, and there was some evidence of correlation between improvements in knowledge and reduction in homophobic sentiment. Conclusions: Scaling up MSM sensitivity training for African HCWs is likely to be a timely, effective and practical means to improve relevant sexual health knowledge and reduce personal homophobic sentiment among HCWs involved in HIV prevention, testing and care in sub-Saharan Africa.

  4. Resposta de biótipos de Euphorbia heterophylla a doses de glyphosate Response of Euphorbia heterophylla biotypes to glyphosate rates

    OpenAIRE

    Vargas, L.; M.A. Nohatto; D. Agostinetto; Bianchi, M.a.; Gonçalves, E.M.; R.E. Toledo

    2011-01-01

    A leiteira (Euphorbia heterophylla) é uma planta daninha de ciclo anual encontrada com frequência em lavouras de soja na região Sul do Brasil, controlada em lavouras de soja geneticamente modificada (Roundup Ready® - RR) com uso do herbicida glyphosate. Entretanto, nos últimos anos, o controle dessa espécie não tem sido satisfatório em alguns locais, provocando a suspeita de que foram selecionados biótipos resistentes ao herbicida. Diante disso, o objetivo deste trabalho foi avaliar, por meio...

  5. Principais aspectos da resistência de plantas daninhas ao herbicida glyphosate / Main aspects on weed herbicide resistance to glyphosate

    Scientific Electronic Library Online (English)

    P.J., Christoffoleti; R., López-Ovejero.

    2003-12-01

    Full Text Available A seleção de biótipos de plantas daninhas resistentes a herbicidas na agricultura brasileira e mundial é um fenômeno já constatado e relatado para praticamente todos os herbicidas em uso na agricultura. A confirmação de um novo caso de resistência de planta daninha ao herbicida glyphosate através da [...] espécie Lolium multiflorum (azevém), que corresponde ao primeiro caso relatado no Brasil para esse herbicida, preocupa o meio científico, produtivo e industrial, devido à importância desse herbicida para o manejo de plantas daninhas das diversas culturas. Assim, a discussão e compreensão do fenômeno da resistência são fundamentais para prevenir ou retardar a seleção de biótipos resistentes a herbicidas, sendo este o objetivo principal do presente artigo. São discutidos aspectos referentes a fatores ligados às plantas daninhas e aos sistemas de produção que interagem na seleção da resistência a herbicidas, o potencial de seleção de plantas daninhas resistentes ao glyphosate, o fluxo gênico e as formas de manejo e prevenção da resistência. Abstract in english The weed biotypes resistant to herbicides in the Brazilian and worldwide agriculture is a phenomenon reported for most of the herbicides in use in the agriculture. The confirmation of a new case of weed resistant to glyphosate by the species Lolium multiflorum that correspond to the first case in Br [...] azil for this herbicide, leave the weed scientist, producers and industrial media concerned due to the importance of this herbicide for weed management in several crops. Therefore, the discussion and understanding of the resistance phenomenon is fundamental to delay or avoid the selection herbicide resistant weed biotypes, being this the main objective of this article. It is discussed aspects related to factors related to the weeds and cropping systems that interact in the selection of herbicide resistance, the potential of weed resistant to glyphosate, gene flow, and ways to delay or avoid resistance.

  6. Glyphosate em mistura com herbicidas alternativos para o manejo de plantas daninhas Glyphosate combined with alternative herbicides for vegetation management

    OpenAIRE

    P.A Monquero; P.J. Christoffoleti; C.T.D. Santos

    2001-01-01

    O uso intensivo de glyphosate como herbicida não-seletivo tem selecionado espécies de plantas daninhas tolerantes. Dessa forma, é importante que sejam estudadas misturas de tanque com herbicidas de mecanismos de ação alternativos e que apresentem efeitos sinergísticos ou aditivos. Por essa razão, foi instalado um experimento inteiramente casualizado, composto por 13 tratamentos e 4 repetições, em casa de vegetação da Universidade de São Paulo - ESALQ/USP, Piracicaba-SP, com as plantas daninha...

  7. Fate and transport of glyphosate and aminomethylphosphonic acid in surface waters of agricultural basins

    Science.gov (United States)

    Gregoire, Caroline; Capel, Paul D.; Coupe, Richard H.; Kalkhoff, Stephen J.

    2011-01-01

    BACKGROUND: Glyphosate [N-(phosphonomethyl)glycine] is a herbicide used widely throughout the world in the production of many crops and is heavily used on soybeans, corn and cotton. Glyphosate is used in almost all agricultural areas of the United States, and the agricultural use of glyphosate has increased from less than 10 000 Mg in 1992 to more than 80 000 Mg in 2007. The greatest intensity of glyphosate use is in the midwestern United States, where applications are predominantly to genetically modified corn and soybeans. In spite of the increase in usage across the United States, the characterization of the transport of glyphosate and its degradate aminomethylphosphonic acid (AMPA) on a watershed scale is lacking.

  8. Is the growth stimulation by low doses of glyphosate sustained over time?

    Energy Technology Data Exchange (ETDEWEB)

    Cedergreen, Nina [Department of Agricultural Sciences, Faculty of Life Science, University of Copenhagen, Hojbakkegard Alle 13, 2630 Tastrup (Denmark)], E-mail: ncf@life.ku.dk

    2008-12-15

    The herbicide, glyphosate, has been shown to stimulate growth in a range of species when applied at doses of 5-60 g a.e. ha{sup -1}, corresponding to realistic spray drift events. This study investigates growth of shoot parameters over time to detect whether the glyphosate induced growth increase was sustained and had a final effect on reproduction. The results showed that an actual biomass growth rate increase took place within the first week after spraying with glyphosate doses <60 g a.e. ha{sup -1}. This initial growth boost kept treated plants larger than untreated plants for up to six weeks, but at harvest there was no significant difference between control plants and treated plants. Possible effects of glyphosate hormesis on the competitive ability of spray drift affected plants are discussed. - Glyphosate induced hormesis in barley is not sustained over time.

  9. Is the growth stimulation by low doses of glyphosate sustained over time?

    International Nuclear Information System (INIS)

    The herbicide, glyphosate, has been shown to stimulate growth in a range of species when applied at doses of 5-60 g a.e. ha-1, corresponding to realistic spray drift events. This study investigates growth of shoot parameters over time to detect whether the glyphosate induced growth increase was sustained and had a final effect on reproduction. The results showed that an actual biomass growth rate increase took place within the first week after spraying with glyphosate doses -1. This initial growth boost kept treated plants larger than untreated plants for up to six weeks, but at harvest there was no significant difference between control plants and treated plants. Possible effects of glyphosate hormesis on the competitive ability of spray drift affected plants are discussed. - Glyphosate induced hormesis in barley is not sustained over time

  10. Impact of glyphosate-tolerant soybean and glufosinate-tolerant corn production on herbicide losses in surface runoff.

    Science.gov (United States)

    Shipitalo, Martin J; Malone, Robert W; Owens, Lloyd B

    2008-01-01

    Residual herbicides used in the production of soybean [Glycine max (L.) Merr] and corn (Zea mays L.) are often detected in surface runoff at concentrations exceeding their maximum contaminant levels (MCL) or health advisory levels (HAL). With the advent of transgenic, glyphosate-tolerant soybean and glufosinate-tolerant corn this concern might be reduced by replacing some of the residual herbicides with short half-life, strongly sorbed, contact herbicides. We applied both herbicide types to two chiseled and two no-till watersheds in a 2-yr corn-soybean rotation and at half rates to three disked watersheds in a 3-yr corn/soybean/wheat (Triticum aestivum L.)-red clover (Trifolium pratense L.) rotation and monitored herbicide losses in runoff water for four crop years. In soybean years, average glyphosate loss (0.07%) was approximately 1/7 that of metribuzin (0.48%) and about one-half that of alachlor (0.12%), residual herbicides it can replace. Maximum, annual, flow-weighted concentration of glyphosate (9.2 microg L(-1)) was well below its 700 microg L(-1) MCL and metribuzin (9.5 microg L(-1)) was well below its 200 microg L(-1) HAL, whereas alachlor (44.5 microg L(-1)) was well above its 2 microg L(-1) MCL. In corn years, average glufosinate loss (0.10%) was similar to losses of alachlor (0.07%) and linuron (0.15%), but about one-fourth that of atrazine (0.37%). Maximum, annual, flow-weighted concentration of glufosinate (no MCL) was 3.5 microg L(-1), whereas atrazine (31.5 microg L(-1)) and alachlor (9.8 microg L(-1)) substantially exceeded their MCLs of 3 and 2 microg L(-1), respectively. Regardless of tillage system, flow-weighted atrazine and alachlor concentrations exceeded their MCLs in at least one crop year. Replacing these herbicides with glyphosate and glufosinate can reduce the occurrence of dissolved herbicide concentrations in runoff exceeding drinking water standards. PMID:18268303

  11. Influência de pontas de pulverização e adjuvantes na deriva em caldas com glyphosate / Influence on spray drift of nozzles and adjuvants with a glyphosate spray solution

    Scientific Electronic Library Online (English)

    Marco Antonio, Gandolfo; Rodolfo Glauber, Chechetto; Fernando Kassis, Carvalho; Ulisses Delvaz, Gandolfo; Eder Dias de, Moraes.

    2013-09-01

    Full Text Available O uso inadequado da tecnologia de aplicação de agrotóxicos, relacionados ao uso de pontas de pulverização e adição de adjuvantes, resulta diretamente em um maior risco de deriva. Objetivou-se como trabalho quantificar a deriva gerada por pontas de pulverização com e sem indução de ar, em aplicações [...] de glyphosate e adjuvantes. O experimento foi realizado em túnel de vento, com o herbicida glyphosate isolado ou em mistura com ureia ou adjuvante redutor de deriva (LI700). As coletas foram realizadas, com fios de polietileno, nas distâncias de 5,0; 10,0 e 15,0 m em relação à barra e nas alturas de 0,2; 0,4; 0,6; 0,8 e 1,0 m em relação ao piso do túnel, a deriva foi aferida por meio do processo de condutividade elétrica. Os resultados apresentaram maior deriva nas menores alturas, tendo igual comportamento para todas as caldas e em todas as distâncias. A ponta de jato plano com indução de ar (AVI 110-015) proporcionou menor deriva em relação à ponta jato plano padrão (AXI 110-015), para todas as caldas avaliadas. Para a ponta de jato plano padrão o acréscimo de adjuvante reduziu a deriva para as três distâncias avaliadas em relação à calda contendo somente o herbicida. Já para a ponta de jato plano com indução de ar a ureia elevou a deriva para todas as distâncias em relação às outras caldas. A ureia pode ser utilizada em aplicações com o modelo de ponta jato plano padrão, por diminuir os riscos de deriva. Abstract in english The improper use of pesticide-application technology, related to the use of spray nozzles and the addition of adjuvants, is directly related to a greater risk of drift. This study aimed to quantify the spray drift generated by nozzles, both with and without air induction, in applications of glyphosa [...] te and adjuvants. The experiment was conducted in a wind tunnel, using the herbicide, glyphosate, either pure or in combination with urea or a drift-reducing adjuvant (LI700). Collections were made on polyethylene strings, at distances of 5.0, 10.0 and 15.0 m from the spray-boom, and at heights of 0.2, 0.4, 0.6, 0.8 and 1.0 m from the floor of the tunnel; the drift was measured using a process of electrical conductivity. The results showed greater drift at the lower heights, giving the same results for all solutions and at all distances. The flat nozzle with air induction (AVI 110-015) gave a smaller drift relative to the standard flat nozzle (AXI 110-015) for all solutions tested. With the standard flat nozzle, adding an adjuvant reduced the drift at the three distances tested, for the solution containing pure herbicide. For the flat fan nozzle with air induction however, the urea increased drift at all distances compared to other the spray solutions. Urea can be employed in applications where the standard flat tip model is used, as it reduces the risk of drift.

  12. Precipitation sensitivity to alloy composition in Fe-Cr-Mn austenitic steels developed for reduced activation for fusion application

    International Nuclear Information System (INIS)

    Special austenitic steels are being designed in which alloying elements like Mo, Nb, and Ni are replaced with Mn, W, V, Ti, and/or Ta to reduce the long-term radioactivity induced by fusion reactor irradiation. However, the new steels still need to have properties otherwise similar to commercial steels like type 316. Precipitation strongly affects strength and radiation-resistance in austenitic steels during irradiation at 400--600/degree/C, and precipitation is also usually quite sensitive to alloy composition. The initial stage of development was to define a base Fe-Cr-Mn-C composition that formed stable austenite after annealing and cold-working, and resisted recovery or excessive formation of coarse carbide and intermetallic phases during elevated temperature annealing. These studies produced a Fe-12Cr-20Mn-0.25C base alloy. The next stage was to add the minor alloying elements W, Ti, V, P, and B for more strength and radiation-resistance. One of the goals was to produce fine MC precipitation behavior similar to the Ti-modified Fe-Cr-Ni prime candidate alloy (PCA). Additions of Ti+V+P+B produced fine MC precipitation along network dislocations and recovery/recrystallization resistance in 20% cold worked material aged at 800/degree/C for 166h, whereas W, Ti, W+Ti, or Ti+P+B additions did not. Addition of W+Ti+V+P+B also produced fine MC, but caused some ? phase formation and more recrystallization as well. 29 refs., 14 figs., 9 tabs

  13. Precipitation sensitivity to alloy composition in Fe-Cr-Mn austenitic steels developed for reduced activation for fusion application

    Energy Technology Data Exchange (ETDEWEB)

    Maziasz, P.J.; Klueh, R.L.

    1988-01-01

    Special austenitic steels are being designed in which alloying elements like Mo, Nb, and Ni are replaced with Mn, W, V, Ti, and/or Ta to reduce the long-term radioactivity induced by fusion reactor irradiation. However, the new steels still need to have properties otherwise similar to commercial steels like type 316. Precipitation strongly affects strength and radiation-resistance in austenitic steels during irradiation at 400--600/degree/C, and precipitation is also usually quite sensitive to alloy composition. The initial stage of development was to define a base Fe-Cr-Mn-C composition that formed stable austenite after annealing and cold-working, and resisted recovery or excessive formation of coarse carbide and intermetallic phases during elevated temperature annealing. These studies produced a Fe-12Cr-20Mn-0.25C base alloy. The next stage was to add the minor alloying elements W, Ti, V, P, and B for more strength and radiation-resistance. One of the goals was to produce fine MC precipitation behavior similar to the Ti-modified Fe-Cr-Ni prime candidate alloy (PCA). Additions of Ti+V+P+B produced fine MC precipitation along network dislocations and recovery/recrystallization resistance in 20% cold worked material aged at 800/degree/C for 166h, whereas W, Ti, W+Ti, or Ti+P+B additions did not. Addition of W+Ti+V+P+B also produced fine MC, but caused some sigma phase formation and more recrystallization as well. 29 refs., 14 figs., 9 tabs.

  14. Temporal Patterns of Glyphosate Leaching at a Loamy Agricultural Field in Denmark

    DEFF Research Database (Denmark)

    NØrgaard, Trine; MØldrup, Per

    2013-01-01

    Glyphosate is a herbicide used worldwide for weed control in agriculture. Glyphosate is believed to pose a low risk for groundwater reservoirs due to its strong sorption to soil minerals and fast degradation. However, during the last ten years several studies have shown detections of glyphosate in drainage water and groundwater at concentrations exceeding the EU drinking water quality criterion of 0.1 µg L-1. This study presents a unique 12-year time series of monitoring results for glyphosate (applied five times during the period) and its degradation product (AMPA) at a cultivated, highly-structured loamy field (Estrup) located in southern Denmark. The Estrup field is part of the Danish Pesticide Leaching Assessment Program (PLAP), which monitors and evaluates pesticide leaching from five differently textured agricultural fields in Denmark. The study investigates the effect of successive glyphosate applications in combination with the effect of precipitation events, drain water runoff, soil water content at 25 cm soil depth, management, and particle leaching patterns, and compares this with monitored field-scale glyphosate and AMPA leaching to a tile drainage system. Preliminary findings indicate that there is an accumulation of glyphosate and AMPA in the soil after the successive applications of glyphosate, as the level of the peaking concentrations right after applications increases. Furthermore, large precipitation events with subsequent high drain water runoff together with management, especially plowing and harvesting, trigger the leaching of mobile colloids, glyphosate, and AMPA. As a likely consequence, glyphosate has occasionally been detected in groundwater monitoring wells installed at the location down to 3.5-4.5 m depth in concentrations exceeding the EU drinking water quality criterion.

  15. Physiological, morphological and biochemical studies of glyphosate tolerance in Mexican Cologania (Cologania broussonetii (Balb.) DC.).

    Science.gov (United States)

    Alcántara de la Cruz, Ricardo; Barro, Francisco; Domínguez-Valenzuela, José Alfredo; De Prado, Rafael

    2016-01-01

    In recent years, glyphosate-tolerant legumes have been used as cover crops for weed management in tropical areas of Mexico. Mexican cologania (Cologania broussonetii (Balb.) DC.) is an innate glyphosate-tolerant legume with a potential as a cover crop in temperate areas of the country. In this work, glyphosate tolerance was characterized in two Mexican cologania (a treated (T) and an untreated (UT)) populations as being representatives of the species, compared in turn to a glyphosate-susceptible hairy fleabane (S) (Conyza bonariensis (L.) Cronq.) population. Experiments revealed that T and UT Mexican cologania populations had a higher tolerance index (TI), and a lower shikimic acid accumulation and foliar retention than the hairy fleabane S population. Absorption and translocation, leaf morphology and metabolism studies were only carried out in the Mexican cologania T population and the hairy fleabane S population. The latter absorbed 37% more (14)C-glyphosate compared to the Mexican cologania T at 96 h after treatment (HAT). Mexican cologania T translocated less herbicide from the treated leaf to the remainder of the plant than hairy fleabane S. The Mexican cologania T presented a greater epicuticular wax coverage percentage than the hairy fleabane S. This morphological characteristic contributed to the low glyphosate absorption observed in the Mexican cologania. In addition, the Mexican cologania T metabolized glyphosate mainly into AMPA, formaldehyde and sarcosine. These results indicate that the high glyphosate tolerance observed in Mexican cologania is mainly due to the poor penetration and translocation of glyphosate into the active site, and the high glyphosate degradation into non-toxic substances. PMID:26646239

  16. Growth and Reproduction of Glyphosate-Resistant and Susceptible Populations of Kochia scoparia

    Science.gov (United States)

    Kumar, Vipan; Jha, Prashant

    2015-01-01

    Evolution of glyphosate-resistant kochia is a threat to no-till wheat-fallow and glyphosate-resistant (GR) cropping systems of the US Great Plains. The EPSPS (5-enol-pyruvylshikimate-3-phosphate synthase) gene amplification confers glyphosate resistance in the tested Kochia scoparia (L.) Schrad populations from Montana. Experiments were conducted in spring to fall 2014 (run 1) and summer 2014 to spring 2015 (run 2) to investigate the growth and reproductive traits of the GR vs. glyphosate-susceptible (SUS) populations of K. scoparia and to determine the relationship of EPSPS gene amplification with the level of glyphosate resistance. GR K. scoparia inbred lines (CHES01 and JOP01) exhibited 2 to 14 relative copies of the EPSPS gene compared with the SUS inbred line with only one copy. In the absence of glyphosate, no differences in growth and reproductive parameters were evident between the tested GR and SUS inbred lines, across an intraspecific competition gradient (1 to 170 plants m-2). GR K. scoparia plants with 2 to 4 copies of the EPSPS gene survived the field-use rate (870 g ha-1) of glyphosate, but failed to survive the 4,350 g ha-1 rate of glyphosate (five-times the field-use rate). In contrast, GR plants with 5 to 14 EPSPS gene copies survived the 4,350 g ha-1 of glyphosate. The results from this research indicate that GR K. scoparia with 5 or more EPSPS gene copies will most likely persist in field populations, irrespective of glyphosate selection pressure. PMID:26580558

  17. Efeito da deriva simulada de glyphosate no crescimento inicial de plantas de pinhão-manso / Effect of simulated glyphosate drift on the initial growth of physic nut plants

    Scientific Electronic Library Online (English)

    N.V, Costa; E.A.L, Erasmo; P.A, Queiroz; D.F, Dornelas; B.F, Dornelas.

    2009-12-01

    Full Text Available Objetivou-se avaliar o efeito da deriva simulada do herbicida glyphosate no crescimento inicial de plantas de pinhão-manso (Jatropha curcas) em casa de vegetação. Para simulação da deriva de glyphosate, utilizaram-se as seguintes doses: 0,0; 1,4; 2,8; 5,6; 11,3; 22,5; 45,0; 90,0; 180,0; e 360,0 g ha [...] -1 de glyphosate, distribuídas em blocos casualizados, com quatro repetições. O glyphosate foi aplicado 51 dias após a semeadura, quando as plantas de pinhão-manso apresentavam entre 16 e 18 folhas completamente desenvolvidas e altura média de 45 cm. As aplicações das doses foram feitas com pulverizador costal pressurizado a CO 2, regulado para proporcionar 200 L ha-1. Os resultados indicam que a altura, o diâmetro do caule, a área foliar, bem como a massa seca de folha, caule e raiz das plantas de pinhão-manso, apresentaram reduções após a simulação da deriva de glyphosate, em relação à testemunha. Dessa forma, pode-se concluir que o desenvolvimento inicial das plantas de pinhão-manso foi influenciado pela deriva simulada de glyphosate; a deriva de doses superiores a 45,0 g ha-1 pode ser severamente prejudicial às plantas no período de 41 dias após a aplicação. Abstract in english This work aimed to evaluate the effect of simulated glyphosate drift on the initial growth of physic nut plants (Jatropha curcas) under greenhouse conditions. The experimental design was a randomized block with four replications. To simulate drift, glyphosate was used at the following rates: 0.0, 1. [...] 4, 2.8, 5.6, 11.3, 22.5, 45.0, 90.0, 180.0 and 360.0 g ha-1, distributed in randomized blocks with four replications. Glyphosate was applied 51 days after sowing, when the plants displayed between 16 and 18 fully developed leaves and 45 cm height. A backpack sprayer was used, pressurized to CO2 and adjusted to provide spraying consumption of 200 L ha-1. The results indicated that height, stem diameter, leaf area and dry mass of leaf, stem and root of the physic nut plants showed reductions after glyphosate drift simulation, compared with the control. Thus, it can be concluded that the initial growth of the physic nut plants was influenced by simulated glyphosate drift, and that the drift of rates higher than 45.0 g ha-1 can cause severe damage to the plants during the period of 41 days after application.

  18. Curvas dose-resposta em espécies de plantas daninhas com o uso do herbicida glyphosate(1 Dose-response curves in weed species with the use of herbicide glyphosate

    Directory of Open Access Journals (Sweden)

    André Luiz de Souza Lacerda

    2004-01-01

    Full Text Available Com o objetivo de verificar a resposta de diferentes espécies de plantas daninhas ao herbicida glyphosate, foi desenvolvido em câmara de crescimento um experimento inteiramente casualizado, com cinco repetições no Departamento de Produção Vegetal da ESALQ/USP. Para isso, foram estudadas seis espécies de plantas daninhas: Bidens pilosa L., Tridax procumbens L., Digitaria insularis (L. Fedde, Spermacoce latifolia Aubl., Ipomoea grandifolia L. e Commelina benghalensis L. Utilizou-se o herbicida glyphosate, inibidor da enzima EPSPs, com doses em escalas de 0,0; 11,3; 22,5; 45; 90; 180; 360; 720 e 1.440 g.ha-1 i.a. A elaboração das curvas dose-resposta foi feita pelo ajuste da equação dos dados coletados de biomassa verde utilizando o modelo log-logístico: Y = C+D-C / 1 + Exp{b[log(x-log(RC50]}, calculado por modelo estatístico não linear dos dados pelo programa estatístico SAS. Após a determinação das curvas dose-resposta nas espécies acima citadas concluiu-se que Bidens pilosa foi considerada a planta daninha mais suscetível ao herbicida glyphosate, pois apresentou menor RC50 (31,86 g.ha-1 i.a.. As espécies Tridax procumbens, Digitaria insularis, Spermacoce latifolia, Ipomoea grandifolia, Commelina benghalensis obtiveram RC50 de 58,40; 128,50; 250,44; 615,49 e >1.440 g.ha-1 i.a. respectivamente. Portanto, a quantidade necessária de herbicida para reduzir em 50% a biomassa verde foi de 1,83; 4,03; 7,86; 32 e >359,56 vezes maior em relação à Bidens pilosa respectivamente.With the objective of veryfing the response of different doses in species of weeds by herbicide glyphosate, an experiment was conducted in growth chamber in a completetly randomized design with three repetitions, in the Department of Vegetable Production at ESALQ/USP. For that, were chosen six species of weeds: Bidens pilosa L., Tridax procumbens L., Digitaria insularis (L. Feed, Spermacoce latifolia Aubl., Ipomoea grandifolia L. and Commelina benghalensis L. The herbicide glyphosate, inhibitor of the enzyme EPSPs, was used at rate 0.0; 11.3; 22.5; 45; 90; 180; 360; 720 and 1440 g.ha-1 a.i. Curves of dose-response were made by the adjustment of the equation of the collected data of green biomass using the log-logistic model: Y = C+D-C / 1 + Exp{b[log(x-log(RC50]}, calculated by the no linear statistical model through the SAS statistical program. After the determination of the dose-response curves for the species mentioned above the Bidens pilosa was considered the most susceptible weed to glyphosate, showing the houvest RC50 (31.86 g.ha-1 a.i.. The species Tridax procumbens, Digitaria insularis, Spermacoce latifolia, Ipomoea grandifolia and Commelina benghalensis obtained RC50 equal to 58.40; 128.50; 250.44; 615.49 and > 1440.00 g.ha-1 a.i., respectively, what means that the necessary amount of herbicide to reduce in 50% the green biomass was 1.83; 4.03; 7.86; 19.31 and >359.56 times higher in relation the Bidens pilosa.

  19. Desempenho da soja roundup ready sob aplicação de glyphosate em diferentes estádios Performance of roundup ready soybean under glyphosate application at different stages

    OpenAIRE

    L.P. Albrecht; Barbosa, A.P.; A.F.M Silva; M.A Mendes; L.M Maraschi-Silva; A.J.P Albrecht

    2011-01-01

    Em razão de estudos e especulações envolvendo a questão da soja RR sob aplicação de glyphosate, são necessárias investigações que permitam esclarecer melhor essa situação. O presente trabalho teve por objetivo avaliar o desempenho agronômico e os teores de óleo e proteínas sob aplicação do herbicida glyphosate na cultura da soja transgênica. Para isso, foi desenvolvido um ensaio em delineamento em blocos casualizados, com quatro repetições, em que os tratamentos avaliados consistiram da pulve...

  20. Dessecação de plantas daninhas com glyphosate em mistura com ureia ou sulfato de amônio Weed desiccation with glyphosate mixed with urea or ammonium sulfate

    OpenAIRE

    S.J.P. Carvalho; V. Damin; A.C.R Dias; M.S.C Melo; Nicolai, M.; P.J. Christoffoleti

    2009-01-01

    O glyphosate é um herbicida não-seletivo, sistêmico, usado para controle de plantas daninhas anuais e perenes em todo o mundo. A absorção da molécula do glyphosate ocorre pelos tecidos fotossinteticamente ativos das plantas, porém alguns fatores podem reduzir sua eficácia, como a morfologia e diversidade de espécies, chuva após aplicação, qualidade da água e misturas em tanque com outros defensivos, entre outros. Objetivou-se com este trabalho avaliar a influência da adição de sulfato de amôn...

  1. The Fate and Transport of Glyphosate and its Degradation Product, Aminomethylphosphonic Acid (AMPA), in Water

    Science.gov (United States)

    Scribner, E.; Meyer, M. T.

    2006-05-01

    Since 2001, the U.S. Geological Survey (USGS) has investigated the fate and transport of glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), in surface water, and more recently in tile-drain flow, soil, and wet deposition. According to U.S. Environmental Protection Agency sources, glyphosate is among the world's most widely used herbicides. In 2004, glyphosate usage estimates indicated that between 103 and 113 million pounds were applied annually to crops in the United States. The use of glyphosate over a wide geographic area suggests that this herbicide might be a potential concern for air, water, and soil quality as well as measured in high concentrations in streams; therefore, it is important to monitor its fate and transport in ground-water/surface-water systems. National, regional, and field-scale studies conducted by the USGS National Water-Quality Assessment and Toxic Substance Hydrology Programs have studied the fate and transport of glyphosate in overland flow, tile- drain flow, surface water, soil, and wet-deposition samples. The samples were analyzed for glyphosate and AMPA by using derivatization and online solid-phase extraction with liquid chromatography/mass spectrometry (LC/MS) and LC/MS/MS methods developed by the USGS Organic Geochemistry Research Laboratory in Lawrence, Kansas. During spring, summer, and fall 2002 runoff periods in 50 Midwestern streams, glyphosate was detected at or above the 0.10 micrograms per liter detection limit in 35, 41, and 31 percent of samples, respectively. AMPA was detected in 53, 82, and 75 percent of samples, respectively. Results of 128 samples from a field study showed that glyphosate was transported as a narrow high- concentration pulse during the first period of runoff after application and that the concentration of glyphosate in runoff was greater than the concentration of AMPA. In tile-drain flow, glyphosate and AMPA were transported in a broad low-concentration pulse during these same runoff periods with glyphosate concentrations only slightly exceeding AMPA concentrations. Seasonal distribution of glyphosate and AMPA was also evident in soil and wet-deposition samples. These variously scaled studies indicate that glyphosate and AMPA are readily detected in surface water in high-use areas through spring and fall and that they are transported to surface water via overland-flow runoff and tile-drain flow.

  2. A composite catalyst of reduced black TiO2-x/CNT: a highly efficient counter electrode for ZnO-based dye-sensitized solar cells.

    Science.gov (United States)

    Zhang, Chunyang; Xie, Yahong; Ma, Junhong; Hu, Jing; Zhang, Cancan

    2015-12-21

    A composite catalyst (reduced black TiO2-x/carbon nanotube) was synthesized through a simple sol-gel method and applied as a counter electrode (CE) in ZnO-based dye-sensitized solar cells (DSSCs). This material demonstrated notable electrocatalytic activity for I3(-) reduction, and the resultant DSSCs achieved a PCE of 5.71%. PMID:26473174

  3. Degradation of the commercial herbicide glyphosate by photo-fenton process: evaluation of kinetic parameters and toxicity

    Scientific Electronic Library Online (English)

    Danilo R. de, Souza; Alam G., Trovó; Nelson R., Antoniosi Filho; Marcos A. A., Silva; Antonio E. H., Machado.

    2013-09-01

    Full Text Available Parâmetros que influenciam a eficiência da degradação do glifosato (adição única de Fe2+, adição simultânea de Fe2+ e Fe3+ numa razão molar de 1:1 (Fe2+/Fe3+), adição de íons oxalato e de H2O2) foram avaliados em escala de laboratório. Efeitos sinérgicos sobre a degradação e formação de fosfato fora [...] m observados utilizando a adição simultânea de Fe2+/Fe3+, bem como adicionando oxalato. Por outro lado, aumentos nas concentrações de Fe2+/Fe3+, oxalato e H2O2 não proporcionaram incremento linear da mineralização de glifosato e liberação de fosfato. Utilizando concentrações elevadas dessas espécies, a eficiência de mineralização de glifosato e de liberação de fosfato foi constante ou até mesmo reduzida. Sob condições otimizadas (0,27 mmol?L-1 de Fe2+/Fe3+; 1,13 mmol?L-1 de oxalato e 10,3 mmol?L-1 de H2O2), os resultados obtidos em escala laboratorial e de planta piloto solar foram próximos. Uma relação direta entre a redução da toxicidade e concentração de glifosato também foi observada. Abstract in english Parameters that influence the efficiency of the degradation of glyphosate (addition of Fe2+, simultaneous addition of Fe2+ and Fe3+ at a 1:1 (Fe2+/Fe3+) molar ratio, addition of oxalate and of H2O2) were evaluated at lab-scale. Synergic effects on its degradation and release of phosphate were observ [...] ed using Fe2+/Fe3+, as well as adding oxalate. On the other hand, the concentration increase of Fe2+/Fe3+, oxalate and H2O2 did not promote a linear increase of glyphosate mineralization and release of phosphate. Using high concentrations of these species, the efficiency of glyphosate mineralization and release of phosphate was constant or even decreased. Under optimized conditions (0.27 mmol?L-1 of Fe2+/Fe3+; 1.13 mmol?L-1 of oxalate and 10.3 mmol?L-1 of H2O2), close results for mineralization and release of phosphate were obtained in lab-scale and using a solar pilot plant. A direct ratio between reducing the toxicity and glyphosate concentration was also observed.

  4. Características da epiderme foliar de eucalipto e seu envolvimento com a tolerância ao glyphosate Characteristics of eucalypt leaf epidermis and its role in glyphosate tolerance

    Directory of Open Access Journals (Sweden)

    L.D. Tuffi Santos

    2006-09-01

    Full Text Available Em áreas de reflorestamento, a deriva do glyphosate causa injúrias nas plantas de eucalipto. Trabalhos preliminares de pesquisa e observações de campo apontam para uma tolerância diferencial ao glyphosate entre os genótipos cultivados. Nesse contexto, objetivou-se estudar as estruturas anatômicas da epiderme foliar de cinco espécies de eucalipto, correlacionando com a tolerância ao glyphosate em deriva simulada. Utilizou-se o esquema fatorial, sendo cinco espécies (Eucalyptus urophylla, E. grandis, E. pellita, E. resinifera e E. saligna e cinco subdoses (0; 43,2; 86,4; 172,8 e 345,6 g e.a. ha-1 de glyphosate, simulando uma deriva. Imediatamente antes da aplicação do herbicida, coletaram-se folhas, totalmente expandidas, para análise anatômica da superfície epidérmica segundo metodologia de dissociação. Entre as espécies estudadas, E. resinifera mostrou-se mais tolerante à deriva de glyphosate, apresentando os menores valores de porcentagem de intoxicação aos 45 dias após aplicação, não sendo encontrada diferença entre as demais espécies. As cinco espécies apresentam folhas glabras, anfiestomáticas, com estômatos do tipo anomocítico e cutícula proeminente. Apesar de presentes em ambas as faces, os estômatos são raros na face adaxial, apresentando baixo índice e densidade estomática. Os maiores valores para índice estomático foram observados em E. resinifera, enquanto E. saligna apresentou a maior densidade estomática. Cavidades subepidérmicas evidenciadas na superfície pelas células de cobertura estão presentes nas cinco espécies, com maior densidade em E. pellita. Houve alta correlação entre a porcentagem de intoxicação por glyphosate e o número de células epidérmicas da superfície adaxial, indicando envolvimento desta característica com a tolerância diferencial ao herbicida. Estudos sobre absorção, translocação e metabolismo do glyphosate em eucalipto devem ser realizados para elucidar o comportamento diferencial de genótipos diante da deriva de glyphosate.In reforestation areas, glyphosate drift causes injuries in Eucalyptus plants. Preliminary research work and field observations point out a differential tolerance to glyphosate among cultivated genotypes. Within this context, the anatomical structures of leaf epidermis of five species of eucalypt, correlated to glyphosate tolerance under simulated drift were studied. The factorial design was used, with the species (Eucalyptus urophylla, E. grandis, E. pellita, E. resinifera and E. saligna and 05 subdoses (0, 43.2, 86.4, 172.8 and 345.6 g e.a. ha-1 of glyphosate simulating a drift. Immediately before herbicide application, totally expanded leaves were collected for anatomical analysis of epidermal surface through dissociation methodology. Among the studied species, E. resinifera was found to be the most tolerant to glyphosate drift, presenting the lowest values for intoxication percentage 45 days post-application, with no difference among the others. The five species present glabrous, amphistomatic leaves with anomocytic type stomata and prominent cuticle. Despite being present on both faces, stomata are rare on the adaxial face, exhibiting low index and stomatic density. The highest values for stomatic index were observed on E. resinifera, while E. saligna presented the highest stomatic density. Subepidermic cavities evidenced on the surface by the overlying cells are present in the five species, with the highest density on E. pellita. A high correlation was found between intoxication percentage and number of epidermic cells on the adaxial surface, indicating the involvement of this characteristic with differential tolerance to the herbicide. Studies on absorption, translocation and metabolism of glyphosate in eucalypt must be undertaken to elucidate the differential behaviour of genotypes concerning glyphosate drift.

  5. Exsudação radicular de glyphosate por Brachiaria decumbens e seus efeitos em plantas de eucalipto / Radicular exudation of glyphosate by Brachiaria decumbens and its effects on eucalypt plant

    Scientific Electronic Library Online (English)

    L.D., Tuffi Santos; J.B., Santos; F.A., Ferreira; J.A., Oliveira; S., Bentivenha; A.F.L., Machado.

    2008-06-01

    Full Text Available Plantas de eucalipto com sintomas de intoxicação por glyphosate são comuns em áreas em que esse herbicida é usado. Uma das possíveis formas de contato com glyphosate é por meio da exsudação radicular do produto, por plantas daninhas tratadas, e subseqüente absorção pelas plantas de eucalipto. Objeti [...] vou-se com este trabalho avaliar a exsudação de glyphosate por Brachiaria decumbens e seus efeitos sobre plantas de eucalipto, por meio da aplicação de 14C-glyphosate misturado à calda de pulverização do produto comercial. Mudas de dois clones de eucalipto (UFV05 e UFV06) foram cultivadas em consórcio com Brachiaria decumbens (capim-braquiária), em vasos contendo dois tipos de solo: um arenoso e outro argiloso. Aos 35 dias após o transplantio das mudas, foram aplicados na braquiária 50 µL da mistura de 14C-glyphosate com a formulação comercial de glyphosate Scout®, utilizando-se uma microsseringa de precisão. Aos 2, 8, 16 e 24 dias após aplicação, as plantas de eucalipto foram coletadas e fracionadas em ápice primário, ápices secundários, folhas e raízes, sendo processadas de acordo com metodologia usual para determinação da radioatividade. Não foram observados sintomas de intoxicação por glyphosate nas plantas de eucalipto, em nenhuma das avaliações realizadas. Entretanto, o 14C-glyphosate foi encontrado em todas as plantas de eucalipto avaliadas, independentemente do solo, do clone e da época de avaliação, em maior concentração em plantas cultivadas no solo arenoso. Os resultados evidenciam a exsudação radicular do glyphosate e/ou de seus metabólitos pela braquiária e subseqüente absorção, via raízes, pelas plantas de eucalipto, em concentrações inferiores às necessárias para causar intoxicação na cultura. Abstract in english Eucalypt plants commonly present symptoms of intoxication in areas where glyphosate is used. One possible way of contamination is through radicular exudation of glyphosate by the treated weed and later, plant absorption. This study aimed to evaluate glyphosate exudation by Brachiaria decumbens and i [...] ts effects on eucalypt plants when 14C-glyphosate, mixed to the solution of the commercial product Scout® was applied. Seedlings of two eucalypt clones (UFV05 and UFV06) were cultivated in pots, intercropped with Brachiaria decumbens, on two types of soil (clayey and sandy). At 35 days after transplantation, 50 µL of the mixture was applied on brachiaria by using a precision micro-syringe. After application, 2, 8, 16 and 24 days, samples of eucalypt plants were collected and fractioned in the primary apices, secondary apices, leaves and roots, following the usual methodology to determine radioactivity. Symptoms of intoxication were not observed in any eucalypt plant evaluation. However, 14C-glyphosate was found in all plants, regardless of the soil type, clone or evaluation time, with the highest concentration being found in the sandy soil. Results show radicular exudation of glyphosate by B. decumbens and its absorption by eucalypt plants through roots. However, concentrations lower than necessary may cause crop intoxication.

  6. Natural Herbicide Resistance (HR to Broad-spectrum Herbicide, Glyphosate among Traditional and Inbred-cultivated Rice (Oryza sativa L. Varieties in Sri Lanka

    Directory of Open Access Journals (Sweden)

    R.G.D. Wijeratne

    2013-01-01

    Full Text Available Weeds along with insect pests and plant diseases are sources of biotic stress in crop systems. Weeds are responsible for serious problems in rice worldwide affecting growth and causing a considerable reduction in quality and quantity in yield. High concentrations of pre-emergent-broad-spectrum systemic herbicide, Glyphosate is prevalently applied to control rice weeds which intern causes severe damages to cultivated rice varieties, susceptible to Glyphosate. However, there may be rice varieties with natural Herbicide Resistance (HR which are so far, has not been evaluated. In this study Six traditional and eighteen developed-cultivated rice varieties (Bg, Bw, At and Ld series developed by Rice Research Development Institute, Sri Lanka were used to screen their natural HR. RCBD with five replicates and three blocks in each treatment-combination was used as the experimental design. As observations, time taken-to seed germination, time taken to flowering; plant height and number of leaves at 12-weeks after sawing, leaf-length, breadth, panicle-length, number of seeds/panicle of resistant plants and controls were recorded. Plants with ?40% resistance were considered as resistant to Glyphosate. Ten inbred-cultivated rice varieties (Bg250, Bg94-1, Bg304, Bg359, Bg406, Bg379-2, Bg366, Bg300, Bw364, At362 and three traditional rice varieties (“Kalu Heenati”, “Sudu Heenati”, “Pachchaperumal” were naturally resistant to 0.25 g L-1 Glyphosate concentration and when increased the concentration (0.5 g L-1 resistance was reduced. This study showed the usefulness of modern statistical method, classification and regression tree analysis (CART in exploring and visualizing the patterns reflected by a large number of rice varieties (larger experimental database on herbicide resistance in future.

  7. Clinical and Virologic Factors Associated with Reduced Sensitivity of Rapid Influenza Diagnostic Tests in Hospitalized Elderly Patients and Young Children

    OpenAIRE

    Chan, Martin C.W.; Lee, Nelson; Karry L. K. Ngai; Leung, Ting F; Chan, Paul K. S.

    2014-01-01

    Rapid influenza diagnostic tests (RIDTs) are commonly used by clinicians to guide patient management. Data on sensitivities among hospitalized patients are limited. Here, we evaluated the clinical and virologic factors affecting the sensitivities of 2 commercially available RIDTs (BinaxNOW Influenza A&B and QuickVue Influenza A+B) on nasopharyngeal aspirate (NPA) specimens collected from elderly patients and young children hospitalized for influenza. Influenza cases and age-matched negative c...

  8. Altering second-order configurations reduces the adaptation effects on early face-sensitive event-related potential components

    OpenAIRE

    Kornél Németh; Stefan Schweinberger; Gyula Kovács

    2014-01-01

    The spatial distances among the features of a face are commonly referred to as second-order relations, and the coding of these properties is often regarded as a cornerstone in face recognition. Previous studies have provided mixed results regarding whether the N170, a face-sensitive component of the event-related potential, is sensitive to second-order relations. Here we investigated this issue in a gender discrimination paradigm following long-term (5 seconds) adaptation to normal or vertica...

  9. Occurrence and fate of the herbicide glyphosate and its degradate aminomethylphosphonic acid in the atmosphere

    Science.gov (United States)

    Chang, Feng-Chih; Simcik, M.F.; Capel, P.D.

    2011-01-01

    This is the first report on the ambient levels of glyphosate, the most widely used herbicide in the United States, and its major degradation product, aminomethylphosphonic acid (AMPA), in air and rain. Concurrent, weekly integrated air particle and rain samples were collected during two growing seasons in agricultural areas in Mississippi and Iowa. Rain was also collected in Indiana in a preliminary phase of the study. The frequency of glyphosate detection ranged from 60 to 100% in both air and rain. The concentrations of glyphosate ranged from 3 and from glyphosate in air were similar or greater to those of the other high-use herbicides observed in the Mississippi River basin, whereas its concentration in rain was greater than the other herbicides. It is not known what percentage of the applied glyphosate is introduced into the air, but it was estimated that up to 0.7% of application is removed from the air in rainfall. Glyphosate is efficiently removed from the air; it is estimated that an average of 97% of the glyphosate in the air is removed by a weekly rainfall ?30?mm.

  10. Effect of formulations on the absorption and translocation of glyphosate in transgenic soybean

    International Nuclear Information System (INIS)

    This study was carried out to evaluate the absorption and translocation of glyphosate formulations in genetically modified (GM) soybean by applying 14C-glyphosate mixed to three glyphosate formulations (Roundup Ready and R. Transorb - both with +isopropylamine salt, and Zapp Qi, formulated from potassic salt ), using a precision micro syringe. Plant samples were collected after herbicide application (4, 16, 40 and 64 hours) and then divided into leaf (trifolium), aerial part, roots and root nodes for radiation reading. 14C-glyphosate that was not absorbed was recovered and counted by washing the leaf with methanol. Penetration and translocation of 14C-glyphosate to the different parts evaluated was found to vary. However, the highest absorption was verified at intervals after 16 hours of application. The highest herbicide percentage in the aerial part of the soybean plants was found when Zapp (potassic salt) was applied on the aerial part and when isopropylamin salt was applied on the roots; 14C-glyphosate was found in the plant root nodules in all treatments, with the highest percentage being observed with R. Transorb, 40 hours after application (0.13% of the total measured or 0.4%, considering only the plant total). Results highlight the hypothesis that glyphosate could harm symbiosis between rhizobium and soybean, since the former also shows in its metabolism EPSPS, which is susceptible to this herbicide. (author)

  11. The effect of glyphosate on the frequency of micronuclei in bovine lymphocytes in vitro

    Directory of Open Access Journals (Sweden)

    Piešova Elena

    2005-01-01

    Full Text Available Glyphosate is a widely used broad-spectrum herbicide that has expanded its applications on plant varieties that are genetically modified to tolerate glyphosate treatment. The aim of this study was to determine the frequency of micronuclei (MNi in bovine peripheral lymphocytes after exposure to glyphosate in vitro. The cytokinesis block micronucleus assay (CBMN for estimation of genotoxic activity was used. The obtained results indicate that glyphosate weakly induced micronuclei in bovine peripheral lymphocytes. Significant elevations of MNi (p <0.05 were observed at concentrations of glyphosate of 280 ?W and 560 ?W, respectively. Treatment of bovine lymphocytes did not result in the induction of micronuclei in a dose-dependent manner. From cytotoxicity data it is evident that CBPI does not reflect the reduction of cell proliferation. The influence of metabolic activation on the genotoxic activity of glyphosate was investigated, too. When lymphocyte cultures were treated with glyphosate together with a liver membrane fraction (S9 from Aroclor 1245-induced rat liver, the number of micronuclei in binucleated cells did not increase significantly.

  12. Interação entre herbicidas inibidores da accase e diferentes formulações de glyphosate no controle de capim-amargoso / Accase and glyphosate diferent formulations herbicides association interactions on sourgrass control

    Scientific Electronic Library Online (English)

    A.A.M., Barroso; A.J.P., Albrecht; F.C., Reis; R.V., Filho.

    2014-09-01

    Full Text Available O glyphosate é um herbicida não seletivo que inibe a produção de aminoácidos aromáticos essenciais à sobrevivência de plantas. Esse herbicida é disponibilizado no mercado em distintas formulações que podem apresentar diferenças no controle de espécies. A mistura de herbicidas é uma ferramenta import [...] ante no controle de plantas daninhas resistentes, sendo uma opção à mistura de inibidores da ACCase ao herbicida glyphosate. Este trabalho contou com a aplicação de diferentes misturas de quatro graminicidas e três formulações de glyphosate em dois estádios vegetativos de plantas de capim-amargoso resistente a esse herbicida. O controle químico foi avaliado por notas visuais de controle, aos 7, 14 e 28 dias após a aplicação, e pela medida de biomassa fresca das plantas, aos 28 dias depois da aplicação. As misturas foram avaliadas como antagonísticas, sinergísticas ou aditivas, segundo o modelo proposto por Colby. Dos tratamentos utilizados, conclui-se que todos são efetivos no manejo da resistência de Digitaria insularis, com exceção do uso de glyphosate isolado, porém o controle deve ser feito em estádios iniciais de desenvolvimento da planta. Em estádios mais desenvolvidos, o melhor controle se deu na associação de quizalofop às formulações sal de amônio e sal potássico de glyphosate; contudo, outras medidas de controle, além da associação de produtos, devem ser tomadas. Abstract in english Glyphosate is a non-selective herbicide that inhibits the production of essential amino acids for plant survival. This herbicide is available in the market in different formulations that can produce different results for weed control. The mixture of herbicides is an important option to control herbi [...] cide resistant weeds, and it is an alternative to mixing ACCase inhibiting herbicides with glyphosate. This work was carried by applying different mixtures of four grass herbicides and 3 glyphosate formulations sprayed at two stages of development of sourgrass. Chemical control was evaluated by visual injury rating at 7, 14 and 28 days after application, and by measuring the fresh weight of the plants at 28 days after the application. The mixtures were classified as antagonistic, synergist or additive according to the model proposed by Colby. All the treatments were effective in the early control of sourgrass except for the application of glyphosate alone. In late applications with more developed plants, the mixture of quizalofop with glyphosate salts (ammonium and potassium) showed better control, but other control measures plus the herbicide mixture should be taken.

  13. Modeling of an equivalent circuit for dye-sensitized solar cells: improvement of efficiency of dye-sensitized solar cells by reducing internal resistance

    International Nuclear Information System (INIS)

    Internal resistance in dye-sensitized nanocrystalline TiO2 solar cells (DSCs) was investigated using electrochemical impedance spectroscopy measurements. Four resistance elements were observed in the impedance spectra. These resistance elements could be explained by variations of cell parameters and the dependence of resistance elements on the applied bias voltage. It is found that the resistance element related to charge transport at the TiO2/dye/electrolyte interface displays behavior like that of a diode, and the series resistance elements largely correspond to the sum of the other resistance elements. To minimize the internal resistance in DSCs, the influence of cell parameters such as sheet resistance of TCO glass substrate, roughness factor of platinum counter electrode and cell thickness, on the impedance spectra were studied. An equivalent circuit for DSCs is proposed based on these results. The combined efforts have led to fabricate an efficient DSC sensitized with black dye. A short circuit photocurrent density of 20.1 mA/cm2, an open-circuit voltage of 0.71 V, a fill factor of 0.71 and an overall conversion efficiency of 10.1% was obtained when measured under standard AM 1.5 sunlight. (authors)

  14. Effect of foliar treatments on distribution of 14C-glyphosate in Convolvulus arvensis L

    International Nuclear Information System (INIS)

    Field bindweed is a perennial weed which produces shoots from buds on its roots. Herbicides, such as glyphosate [N-(phosphonomethyl)glycine] used for control of field bindweed usually do not kill all shoot buds on the roots, thus field bindweed often reinfests areas within 3 to 6 weeks of treatment. This dissertation deals with the development of a technique to change glyphosate distribution in field bindweed roots and could result in less shoot regrowth after glyphosate application. In field studies eight plant growth regulators were applied in September, 3 days before 2.24 kg/ha of 2.4-D[(2,4-dichlorophenoxy) acetic acid] or 1.68 kg/ha of glyphosate. Eight months later, regrowth of shoots was least where glyphosate was applied at 0.028 kg/ha as a pretreatment, followed by a standard rate of 1.68 kg/ha. In subsequent greenhouse studies, typical patterns of shoot growth and 14C-glyphosate distribution in isolated root sections taken from 15-week-old intact plants were determined. In subsequent growth chamber studies, plants were decapitated to observe the effect of shoot apical dominance on 14C-glyphosate translocation. After 14C-glyphosate was applied, intact plants had about twice as much 14C in distal root sections as in proximal or middle root sections. Decapitated plants had more 14C in proximal and middle root sections than in distal sections, and about twice as much 14C was translocated to roots of decapitated plants than intact plants. Eight concentrations of 2,4,-D or glyphosate from 1 to 5000 ppm were applied in logarithmic series to 6-week old plants

  15. Identification of geneticaly modified soybean seeds resistant to glyphosate

    Directory of Open Access Journals (Sweden)

    Tillmann Maria Ângela André

    2004-01-01

    Full Text Available Advances in genetic engineering permit the modification of plants to be tolerant to certain herbicides that are usually not selective. For practical and commercial purposes, it is important to be able to detect the presence or absence of these traits in genotypes. The objective of this research was to develop a procedure for identifying genetically modified soybean (Glycine max L. Merr. with resistance to the herbicide glyphosate. Two studies were conducted based on germination test. In the first study, soybean seeds were pre-imbibed in paper towel with the herbicide solutions, then transferred to moist paper towel for the germination test. In the second study, seeds were placed directly in herbicide solutions in plastic cups and tested for germination using the paper towel method. Eight soybean genotypes were compared: four Roundup Ready, that contained the gene resistant to the herbicide (G99-G725, Prichard RR, G99-G6682, and H7242 RR and four non-transgenic parental cultivars (Boggs, Haskell, Benning, and Prichard. In the first study, the seeds were imbibed for 16 hours at 25°C in herbicide concentrations between 0.0 and 1.5% of the glyphosate active ingredient. In the second, seeds were subjected to concentrations between 0.0 and 0.48%, for one hour, at 30°C. The evaluation parameters were: germination, hypocotyl length, root length and total length of the seedlings. Both methods are efficient in identifying glyphosate-resistant soybean genotypes. It is possible to identify the genetically modified soybean genotypes after three days, by imbibing the seed in 0.12% herbicide solution, and after six days if the substrate is pre-imbibed in a 0.6% herbicide solution. The resistance trait was identified in all cultivars, independent of the initial physiological quality of the seed.

  16. Glyphosate and glufosinate detection at electrogenerated NiAl-LDH thin films

    Energy Technology Data Exchange (ETDEWEB)

    Khenifi, Aicha [Laboratoire des Materiaux Inorganiques, UMR CNRS 6002, Universite Blaise Pascal, Clermont-Ferrand (France); Laboratoire de physico-chimie des materiaux, catalyse et environnement Usto, Oran, El M' nouar (Algeria); Derriche, Zoubir [Laboratoire de physico-chimie des materiaux, catalyse et environnement Usto, Oran, El M' nouar (Algeria); Forano, Claude; Prevot, Vanessa [Laboratoire des Materiaux Inorganiques, UMR CNRS 6002, Universite Blaise Pascal, Clermont-Ferrand (France); Mousty, Christine, E-mail: Christine.Mousty@univ-bpclermont.fr [Laboratoire des Materiaux Inorganiques, UMR CNRS 6002, Universite Blaise Pascal, Clermont-Ferrand (France); Scavetta, Erika, E-mail: scavetta@fci.unibo.it [Laboratorio di Chimica Analitica, Dipartimento di Chimica Fisica ed Inorganica, Universita degli Studi di Bologna (Italy); Ballarin, Barbara; Guadagnini, Lorella; Tonelli, Domenica [Laboratorio di Chimica Analitica, Dipartimento di Chimica Fisica ed Inorganica, Universita degli Studi di Bologna (Italy)

    2009-11-10

    An amperometric sensor based on Ni{sub 1-x}Al{sub x}(OH){sub 2}NO{sub 3x}.nH{sub 2}O layered double hydroxide (LDH) has been developed for the electrochemical analysis in one step of two herbicides: glyphosate (N-(phosphonomethyl)glycine, Glyp) and glufosinate ((DL-homoalanine-4-yl)-methylphosphinic acid, Gluf). NiAl-LDH was prepared by coprecipitation or by electrodeposition at the Pt electrode surface. Inorganic films were fully characterized by X-ray diffraction, Raman spectroscopy and scanning electron microscopy. Adsorption isotherms of Glyp onto this inorganic lamellar material have been established. Electrocatalytic oxidation of Glyp and Gluf is possible at the Ni{sup 3+} centres of the structure. The electrochemical responses of the NiAl-LDH modified electrode were obtained by cyclic voltammetry and chronoamperometry at 0.49 V/SCE as a function of herbicide concentration in 0.1 M NaOH solution. The electrocatalytic response showed a linear dependence on the Glyp concentration ranging between 0.01 and 0.9 mM with a detection limit of 1 {mu}M and sensitivity 287 mA/M cm{sup 2}. The sensitivity found for Gluf was lower (178 mA/M cm{sup 2}).

  17. Glyphosate and glufosinate detection at electrogenerated NiAl-LDH thin films

    International Nuclear Information System (INIS)

    An amperometric sensor based on Ni1-xAlx(OH)2NO3x.nH2O layered double hydroxide (LDH) has been developed for the electrochemical analysis in one step of two herbicides: glyphosate (N-(phosphonomethyl)glycine, Glyp) and glufosinate ((DL-homoalanine-4-yl)-methylphosphinic acid, Gluf). NiAl-LDH was prepared by coprecipitation or by electrodeposition at the Pt electrode surface. Inorganic films were fully characterized by X-ray diffraction, Raman spectroscopy and scanning electron microscopy. Adsorption isotherms of Glyp onto this inorganic lamellar material have been established. Electrocatalytic oxidation of Glyp and Gluf is possible at the Ni3+ centres of the structure. The electrochemical responses of the NiAl-LDH modified electrode were obtained by cyclic voltammetry and chronoamperometry at 0.49 V/SCE as a function of herbicide concentration in 0.1 M NaOH solution. The electrocatalytic response showed a linear dependence on the Glyp concentration ranging between 0.01 and 0.9 mM with a detection limit of 1 ?M and sensitivity 287 mA/M cm2. The sensitivity found for Gluf was lower (178 mA/M cm2).

  18. The influence of organic matter on sorption and fate of glyphosate in soil - Comparing different soils and humic substances

    International Nuclear Information System (INIS)

    Soil organic matter (SOM) is generally believed not to influence the sorption of glyphosate in soil. To get a closer look on the dynamics between glyphosate and SOM, we used three approaches: I. Sorption studies with seven purified soil humic fractions showed that these could sorb glyphosate and that the aromatic content, possibly phenolic groups, seems to aid the sorption. II. Sorption studies with six whole soils and with SOM removed showed that several soil parameters including SOM are responsible for the strong sorption of glyphosate in soils. III. After an 80 day fate experiment, ?40% of the added glyphosate was associated with the humic and fulvic acid fractions in the sandy soils, while this