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Sample records for reduced glyphosate sensitivity

  1. A novel 5-enolpyruvylshikimate-3-phosphate synthase from Rahnella aquatilis with significantly reduced glyphosate sensitivity.

    Science.gov (United States)

    Peng, Ri-He; Tian, Yong-Sheng; Xiong, Ai-Sheng; Zhao, Wei; Fu, Xiao-Yan; Han, Hong-Juan; Chen, Chen; Jin, Xiao-Fen; Yao, Quan-Hong

    2012-01-01

    The 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19) is a key enzyme in the shikimate pathway for the production of aromatic amino acids and chorismate-derived secondary metabolites in plants, fungi, and microorganisms. It is also the target of the broad-spectrum herbicide glyphosate. Natural glyphosate resistance is generally thought to occur within microorganisms in a strong selective pressure condition. Rahnella aquatilis strain GR20, an antagonist against pathogenic agrobacterial strains of grape crown gall, was isolated from the rhizosphere of grape in glyphosate-contaminated vineyards. A novel gene encoding EPSPS was identified from the isolated bacterium by complementation of an Escherichia coli auxotrophic aroA mutant. The EPSPS, named AroA(R. aquatilis), was expressed and purified from E. coli, and key kinetic values were determined. The full-length enzyme exhibited higher tolerance to glyphosate than the E. coli EPSPS (AroA(E. coli)), while retaining high affinity for the substrate phosphoenolpyruvate. Transgenic plants of AroA(R. aquatilis) were also observed to be more resistant to glyphosate at a concentration of 5 mM than that of AroA(E. coli). To probe the sites contributing to increased tolerance to glyphosate, mutant R. aquatilis EPSPS enzymes were produced with the c-strand of subdomain 3 and the f-strand of subdomain 5 (Thr38Lys, Arg40Val, Arg222Gln, Ser224Val, Ile225Val, and Gln226Lys) substituted by the corresponding region of the E. coli EPSPS. The mutant enzyme exhibited greater sensitivity to glyphosate than the wild type R. aquatilis EPSPS with little change of affinity for its first substrate, shikimate-3-phosphate (S3P) and phosphoenolpyruvate (PEP). The effect of the residues on subdomain 5 on glyphosate resistance was more obvious.

  2. A novel 5-enolpyruvylshikimate-3-phosphate synthase from Rahnella aquatilis with significantly reduced glyphosate sensitivity.

    Directory of Open Access Journals (Sweden)

    Ri-He Peng

    Full Text Available The 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19 is a key enzyme in the shikimate pathway for the production of aromatic amino acids and chorismate-derived secondary metabolites in plants, fungi, and microorganisms. It is also the target of the broad-spectrum herbicide glyphosate. Natural glyphosate resistance is generally thought to occur within microorganisms in a strong selective pressure condition. Rahnella aquatilis strain GR20, an antagonist against pathogenic agrobacterial strains of grape crown gall, was isolated from the rhizosphere of grape in glyphosate-contaminated vineyards. A novel gene encoding EPSPS was identified from the isolated bacterium by complementation of an Escherichia coli auxotrophic aroA mutant. The EPSPS, named AroA(R. aquatilis, was expressed and purified from E. coli, and key kinetic values were determined. The full-length enzyme exhibited higher tolerance to glyphosate than the E. coli EPSPS (AroA(E. coli, while retaining high affinity for the substrate phosphoenolpyruvate. Transgenic plants of AroA(R. aquatilis were also observed to be more resistant to glyphosate at a concentration of 5 mM than that of AroA(E. coli. To probe the sites contributing to increased tolerance to glyphosate, mutant R. aquatilis EPSPS enzymes were produced with the c-strand of subdomain 3 and the f-strand of subdomain 5 (Thr38Lys, Arg40Val, Arg222Gln, Ser224Val, Ile225Val, and Gln226Lys substituted by the corresponding region of the E. coli EPSPS. The mutant enzyme exhibited greater sensitivity to glyphosate than the wild type R. aquatilis EPSPS with little change of affinity for its first substrate, shikimate-3-phosphate (S3P and phosphoenolpyruvate (PEP. The effect of the residues on subdomain 5 on glyphosate resistance was more obvious.

  3. Differentiating glyphosate-resistant and glyphosate-sensitive Italian ryegrass using hyperspectral imagery

    Science.gov (United States)

    Lee, Matthew A.; Huang, Yanbo; Nandula, Vijay K.; Reddy, Krishna N.

    2014-05-01

    Glyphosate based herbicide programs are most preferred in current row crop weed control practices. With the increased use of glyphosate, weeds, including Italian ryegrass (Lolium multiflorum), have developed resistance to glyphosate. The identification of glyphosate resistant weeds in crop fields is critical because they must be controlled before they reduce the crop yield. Conventionally, the method for the identification with whole plant or leaf segment/disc shikimate assays is tedious and labor-intensive. In this research, we investigated the use of high spatial resolution hyperspectral imagery to extract spectral curves derived from the whole plant of Italian ryegrass to determine if the plant is glyphosate resistant (GR) or glyphosate sensitive (GS), which provides a way for rapid, non-contact measurement for differentiation between GR and GS weeds for effective site-specific weed management. The data set consists of 226 greenhouse grown plants (119 GR, 107 GS), which were imaged at three and four weeks after emergence. In image preprocessing, the spectral curves are normalized to remove lighting artifacts caused by height variation in the plants. In image analysis, a subset of hyperspectral bands is chosen using a forward selection algorithm to optimize the area under the receiver operating characteristic (ROC) between GR and GS plants. Then, the dimensionality of selected bands is reduced using linear discriminant analysis (LDA). Finally, the maximum likelihood classification was conducted for plant sample differentiation. The results show that the overall classification accuracy is between 75% and 80% depending on the age of the plants. Further refinement of the described methodology is needed to correlate better with plant age.

  4. 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

    , 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.

  5. Shikimate accumulates in both glyphosate-sensitive and glyphosate-resistant horseweed (Conyza canadensis L. Cronq.).

    Science.gov (United States)

    Mueller, Thomas C; Massey, Joseph H; Hayes, Robert M; Main, Chris L; Stewart, C Neal

    2003-01-29

    Horseweed (Conyza canadensis) is a cosmopolitan weed that commonly grows throughout North America. Horseweed that is not completely controlled by normal applications of glyphosate has been reported in western Tennessee. This research had three objectives: (1) to develop and validate an analytical procedure for the quantitative determination of shikimate, an important indicator of glyphosate activity in plants; (2) to confirm resistance to glyphosate in a horseweed population; and (3) to examine the accumulation of shikimate in both glyphosate-resistant and glyphosate-susceptible horseweed plants. The analytical procedure to determine shikimate used extraction with 1 M HCl for 24 h, followed by liquid chromatography using photodiode array detection, and shikimate recoveries were >or=82%. Glyphosate applications of both 0.84 kg ae/ha (the standard application rate) and 3.8 kg ae/ha to susceptible plants caused complete plant death. The same glyphosate applications to putative resistant populations caused less than 15% growth reduction as determined by visual evaluations, and fresh weights of these resistant plants 17 days after glyphosate treatment (DAT) were reduced an average of 45% in one population and were not affected in a different population. This direct comparison conclusively confirms that horseweed plants collected in western Tennessee in 2002 are resistant to 4 times the normal application dosage of glyphosate. The glyphosate-resistant horseweed biotypes still exhibited some herbicidal effects from the glyphosate, such as yellowing in the most actively growing, apical shoot meristems. The yellowing in the shoot apexes was transitory, and the plants recovered from this damage. Shikimate concentrations in all untreated horseweed plants were less than 100 microg/g, which was significantly less than that in all plants which had been treated with 0.84 kg ae/ha of glyphosate. Unexpectedly, shikimate accumulated (>1000 microg/g) in both resistant populations and

  6. Glyphosate reduced seed and leaf concentrations of calcium, manganese, magnesium, and iron in non-glyphosate resistant soybean

    OpenAIRE

    ÇAKMAK, İsmail; Cakmak, Ismail; Yazıcı, M. Atilla; YAZICI, M. Atilla; Tutuş, Yusuf; Tutus, Yusuf; Öztürk, Levent; Ozturk, Levent

    2009-01-01

    Greenhouse experiments were conducted to study the effects of glyphosate drift on plant growth and concentrations of mineral nutrients in leaves and seeds of non-glyphosate resistant soybean plants (Glycine max, L.). Glyphosate was sprayed on plant shoots at increasing rates between 0.06 and 1.2% of the recommended application rate forweed control. In an experiment with 3-week-old plants, increasing application of glyphosate on shoots significantly reduced chlorophyll concentration of the ...

  7. Glyphosate effects on gas exchange and chlorophyll fluorescence responses of two Lolium perenne L. biotypes with differential herbicide sensitivity.

    Science.gov (United States)

    Yanniccari, Marcos; Tambussi, Eduardo; Istilart, Carolina; Castro, Ana María

    2012-08-01

    Despite the extensive use of glyphosate, how it alters the physiology and metabolism of plants is still unclear. Photosynthesis is not regarded to be a primary inhibitory target of glyphosate, but it has been reported to be affected by this herbicide. The aim of the current research was to determine the effects of glyphosate on the light and dark reactions of photosynthesis by comparing glyphosate-susceptible and glyphosate-resistant Lolium perenne biotypes. After glyphosate treatment, accumulation of reduced carbohydrates occurred before a decrease in gas exchange. Stomatal conductance and CO(2) assimilation were reduced earlier than chlorophyll fluorescence and the amount of chlorophyll in susceptible plants. In the glyphosate-resistant biotype, stomatal conductance was the only parameter slightly affected only 5 days post-application. In susceptible plants, the initial glyphosate effects on gas exchange could be a response to a feedback regulation of photosynthesis. Since the herbicide affects actively growing tissues regardless of the inhibition of photosynthesis, the demand of assimilates decreased and consequently induced an accumulation of carbohydrates in leaves. We concluded that stomatal conductance could be a very sensitive parameter to assess both the susceptibility/resistance to glyphosate before the phytotoxic symptoms become evident.

  8. Foliar-applied glyphosate substantially reduced uptake and transport of iron and manganese in sunflower (helianthus annuus L.) plants

    OpenAIRE

    Eker, Selim; Öztürk, Levent; Ozturk, Levent; Yazıcı, Mustafa Atilla; Yazici, Mustafa Atilla; Erenoğlu, Bülent; Erenoglu, Bulent; Romheld, Volker; ÇAKMAK, İsmail; Cakmak, Ismail

    2006-01-01

    Evidence clearly shows that cationic micronutrients in spray solutions reduce the herbicidal effectiveness of glyphosate for weed control due to the formation of metal-glyphosate complexes. The formation of these glyphosate-metal complexes in plant tissue may also impair micronutrient nutrition of nontarget plants when exposed to glyphosate drift or glyphosate residues in soil. In the present study, the effects of simulated glyphosate drift on plant growth and uptake, translocation, and accum...

  9. Foliar-applied glyphosate substantially reduced uptake and transport of iron and manganese in sunflower (Helianthus annuus L.) plants.

    Science.gov (United States)

    Eker, Selim; Ozturk, Levent; Yazici, Atilla; Erenoglu, Bulent; Romheld, Volker; Cakmak, Ismail

    2006-12-27

    Evidence clearly shows that cationic micronutrients in spray solutions reduce the herbicidal effectiveness of glyphosate for weed control due to the formation of metal-glyphosate complexes. The formation of these glyphosate-metal complexes in plant tissue may also impair micronutrient nutrition of nontarget plants when exposed to glyphosate drift or glyphosate residues in soil. In the present study, the effects of simulated glyphosate drift on plant growth and uptake, translocation, and accumulation (tissue concentration) of iron (Fe), manganese (Mn), zinc (Zn), and copper (Cu) were investigated in sunflower (Helianthus annuus L.) plants grown in nutrient solution under controlled environmental conditions. Glyphosate was sprayed on plant shoots at different rates between 1.25 and 6.0% of the recommended dosage (i.e., 0.39 and 1.89 mM glyphosate isopropylamine salt). Glyphosate applications significantly decreased root and shoot dry matter production and chlorophyll concentrations of young leaves and shoot tips. The basal parts of the youngest leaves and shoot tips were severely chlorotic. These effects became apparent within 48 h after the glyphosate spray. Glyphosate also caused substantial decreases in leaf concentration of Fe and Mn while the concentration of Zn and Cu was less affected. In short-term uptake experiments with radiolabeled Fe (59Fe), Mn (54Mn), and Zn (65Zn), root uptake of 59Fe and 54Mn was significantly reduced in 12 and 24 h after application of 6% of the recommended dosage of glyphosate, respectively. Glyphosate resulted in almost complete inhibition of root-to-shoot translocation of 59Fe within 12 h and 54Mn within 24 h after application. These results suggest that glyphosate residues or drift may result in severe impairments in Fe and Mn nutrition of nontarget plants, possibly due to the formation of poorly soluble glyphosate-metal complexes in plant tissues and/or rhizosphere interactions.

  10. Sensitivity of imidazolinone-resistant red rice (Oryza sativa L. to glyphosate and glufosinate

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    Guilherme Vestena Cassol

    2015-09-01

    Full Text Available 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 GR50values 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

  11. 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

    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

  12. Target site mutation and reduced translocation are present in a glyphosate-resistant Lolium multiflorum Lam. biotype from Spain.

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    González-Torralva, Fidel; Gil-Humanes, Javier; Barro, Francisco; Brants, Ivo; De Prado, Rafael

    2012-09-01

    The resistance mechanism of a glyphosate-resistant Lolium multiflorum Lam. biotype collected in Córdoba (Southern Spain) was examined. Resistance Factor values at three different growth stages ranged between 4.77 and 4.91. At 96 hours after treatment (HAT) the S biotype had accumulated seven times more shikimic acid than the R biotype. There were significant differences in translocation of (14)C-glyphosate between biotypes, i.e. at 96 HAT, the R biotype accumulated in the treated leaf more than 70% of the absorbed herbicide, in comparison with 59.21% of the S biotype; the R biotype translocated only 14.79% of the absorbed (14)C-glyphosate to roots, while in the S population this value was 24.79%. Visualization of (14)C-glyphosate by phosphor imaging showed a reduced distribution in the R biotype compared with the S. Glyphosate metabolism was not involved in the resistance mechanism due to both biotypes showing similar values of glyphosate at 96 HAT. Comparison of the EPSPS gene sequences between biotypes indicated that the R biotype has a proline 182 to serine amino acid substitution. In short, the resistance mechanism of the L. multiflorum Lam. biotype is due to an impaired translocation of the herbicide and an altered target site.

  13. Glyphosate resistance in giant ragweed (Ambrosia trifida L.) from Mississippi is partly due to reduced translocation

    Science.gov (United States)

    A giant ragweed population from a glyphosate-resistant (GR) soybean field in Mississippi was suspected to be resistant to glyphosate. Greenhouse and laboratory studies were conducted to confirm and quantify the magnitude of glyphosate resistance in the giant ragweed population and to elucidate the p...

  14. Glyphosate poisoning.

    Science.gov (United States)

    Bradberry, Sally M; Proudfoot, Alex T; Vale, J Allister

    2004-01-01

    does not imply endorsement.) (41% glyphosate as the IPA salt and 15% POEA). There is a reasonable correlation between the amount ingested and the likelihood of serious systemic sequelae or death. Advancing age is also associated with a less favourable prognosis. Ingestion of >85 mL of the concentrated formulation is likely to cause significant toxicity in adults. Gastrointestinal corrosive effects, with mouth, throat and epigastric pain and dysphagia are common. Renal and hepatic impairment are also frequent and usually reflect reduced organ perfusion. Respiratory distress, impaired consciousness, pulmonary oedema, infiltration on chest x-ray, shock, arrythmias, renal failure requiring haemodialysis, metabolic acidosis and hyperkalaemia may supervene in severe cases. Bradycardia and ventricular arrhythmias are often present pre-terminally. Dermal exposure to ready-to-use glyphosate formulations can cause irritation and photo-contact dermatitis has been reported occasionally; these effects are probably due to the preservative Proxel (benzisothiazolin-3-one). Severe skin burns are very rare. Inhalation is a minor route of exposure but spray mist may cause oral or nasal discomfort, an unpleasant taste in the mouth, tingling and throat irritation. Eye exposure may lead to mild conjunctivitis, and superficial corneal injury is possible if irrigation is delayed or inadequate. Management is symptomatic and supportive, and skin decontamination with soap and water after removal of contaminated clothing should be undertaken in cases of dermal exposure.

  15. Glyphosate poisoning.

    Science.gov (United States)

    Bradberry, Sally M; Proudfoot, Alex T; Vale, J Allister

    2004-01-01

    does not imply endorsement.) (41% glyphosate as the IPA salt and 15% POEA). There is a reasonable correlation between the amount ingested and the likelihood of serious systemic sequelae or death. Advancing age is also associated with a less favourable prognosis. Ingestion of >85 mL of the concentrated formulation is likely to cause significant toxicity in adults. Gastrointestinal corrosive effects, with mouth, throat and epigastric pain and dysphagia are common. Renal and hepatic impairment are also frequent and usually reflect reduced organ perfusion. Respiratory distress, impaired consciousness, pulmonary oedema, infiltration on chest x-ray, shock, arrythmias, renal failure requiring haemodialysis, metabolic acidosis and hyperkalaemia may supervene in severe cases. Bradycardia and ventricular arrhythmias are often present pre-terminally. Dermal exposure to ready-to-use glyphosate formulations can cause irritation and photo-contact dermatitis has been reported occasionally; these effects are probably due to the preservative Proxel (benzisothiazolin-3-one). Severe skin burns are very rare. Inhalation is a minor route of exposure but spray mist may cause oral or nasal discomfort, an unpleasant taste in the mouth, tingling and throat irritation. Eye exposure may lead to mild conjunctivitis, and superficial corneal injury is possible if irrigation is delayed or inadequate. Management is symptomatic and supportive, and skin decontamination with soap and water after removal of contaminated clothing should be undertaken in cases of dermal exposure. PMID:15862083

  16. Secondary effects of glyphosate on plants

    Science.gov (United States)

    Glyphosate is a unique herbicide with interesting secondary effects. Unfortunately, some have assumed that the secondary effects that occur in glyphosate-susceptible plants treated with glyphosate, such as altered mineral nutrition, reduced phenolic compound production and pathogen resistance, also ...

  17. A Highly Selective and Sensitive Fluorescence Detection Method of Glyphosate Based on an Immune Reaction Strategy of Carbon Dot Labeled Antibody and Antigen Magnetic Beads.

    Science.gov (United States)

    Wang, Duo; Lin, Bixia; Cao, Yujuan; Guo, Manli; Yu, Ying

    2016-08-01

    A sensitive fluorescence detection method for glyphosate (GLY) was established based on immune reaction. First, carbon dot labeled antibodies (lgG-CDs) which were able to specifically identify glyphosate were prepared with the environmentally friendly carbon dots (CDs) and glyphosate antibody (lgG). lgG-CDs could be used to in situ visualize the distribution of glyphosate in plant tissues. In order to eliminate the effects of excess lgG-CDs on the determination of GLY, antigen magnetic beads Fe3O4-GLY based on magnetic nanoparticles Fe3O4 and glyphosate were constructed and utilized to couple with the excess lgG-CDs. After magnetic separation to remove antigen magnetic beads, there was a linear relationship between the fluorescence intensity of lgG-CDs and the logarithmic concentration of glyphosate in the range of 0.01-80 μg/mL with a detection limit of 8 ng/mL. The method was used for the detection of glyphosate in Pearl River water, tea, and soil samples with satisfactory recovery ratio between 87.4% and 103.7%. PMID:27403652

  18. A Highly Selective and Sensitive Fluorescence Detection Method of Glyphosate Based on an Immune Reaction Strategy of Carbon Dot Labeled Antibody and Antigen Magnetic Beads.

    Science.gov (United States)

    Wang, Duo; Lin, Bixia; Cao, Yujuan; Guo, Manli; Yu, Ying

    2016-08-01

    A sensitive fluorescence detection method for glyphosate (GLY) was established based on immune reaction. First, carbon dot labeled antibodies (lgG-CDs) which were able to specifically identify glyphosate were prepared with the environmentally friendly carbon dots (CDs) and glyphosate antibody (lgG). lgG-CDs could be used to in situ visualize the distribution of glyphosate in plant tissues. In order to eliminate the effects of excess lgG-CDs on the determination of GLY, antigen magnetic beads Fe3O4-GLY based on magnetic nanoparticles Fe3O4 and glyphosate were constructed and utilized to couple with the excess lgG-CDs. After magnetic separation to remove antigen magnetic beads, there was a linear relationship between the fluorescence intensity of lgG-CDs and the logarithmic concentration of glyphosate in the range of 0.01-80 μg/mL with a detection limit of 8 ng/mL. The method was used for the detection of glyphosate in Pearl River water, tea, and soil samples with satisfactory recovery ratio between 87.4% and 103.7%.

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

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    J. Galvani

    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 biótipos 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.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 sensitivities 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

  20. 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

  1. 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.

  2. 牛筋草对草甘膦敏感性测定%The Sensitivity of Eleusine indica to Glyphosate

    Institute of Scientific and Technical Information of China (English)

    方宇; 倪汉文

    2012-01-01

    [Aims] The sensitivity baseline of weed species Eleusine indica and its resistant status to glyphosate were determined in this study. [Methods] Twelve populations from glyphoste-untreated locations were collected and nine populations from glyphosate-treated locations. Their ED10 values were determined by whole plant bioassay method in greenhouse. [Results] The findings from this study showed that the sensitivity baseline was ED50 (312.15±40.94) g a.I./ha. The average ED50 value was (301.65±70.75) g a.I./ha among nine biotypes treated with glyphosate for more than five years. [Conclusions] This result indicated that E. Indica was not resistant on glyphosate in Beijng, Shangdong and Guangxi where the herbicide was used for several years.%[目的]测定我国牛筋草种群对草甘膦的敏感性基线,同时监测了多年使用草甘膦的牛筋草种群的抗性情况.[方法]通过室内整株生测方法确定12个未使用草甘膦的牛筋草种群和9个使用过草甘膦的牛筋草种群对草甘膦的ED50值.[结果]未使用过草甘膦的牛筋草对草甘膦的敏感性基线为(312.15±40.94)g a.i./hm2,多年使用草甘膦的9个牛筋草种群ED50平均值为(301.65±70.75)g a.i./hm2.[结论]试验结果表明在北京、山东和广西等地多年使用草甘膦后,牛筋草种群对该药没有产生抗性.

  3. Impact of seven years of glyphosate resistant corn and glyphosate applications under conventional and reduced tillage on bulk and rhizosphere soil exoenzyme activities and corn root endophytic microbial community structure

    Science.gov (United States)

    Background: Conservation tillage practices across the country have been implementing genetically engineered glyphosate resistant corn crops along with applications of the herbicide glyphosate. We tested the hypothesis that seven years of glyphosate applications to both glyphosate resistant and non-r...

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    Lyndsay E. Saunders

    2013-12-01

    Full Text Available 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 within the ditches may have a differential sensitivity to exposure of the root zone to glyphosate, contributing to patterns of abundance of ruderal species. The present laboratory experiment investigated whether two species commonly found in agricultural ditches in southcentral United States were affected by root zone glyphosate in a dose-dependent manner, with the objective of identifying a sublethal concentration threshold. The root zone of individuals of Polygonum hydropiperoides and Panicum hemitomon were exposed to four concentrations of glyphosate. Leaf chlorophyll content was measured, and the ratio of aboveground biomass to belowground biomass and survival were quantified. The findings from this study showed that root zone glyphosate exposure negatively affected both species including dose-dependent reductions in chlorophyll content. P. hydropiperdoides showed the greatest negative response, with decreased belowground biomass allocation and total mortality at the highest concentrations tested.

  6. 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

  7. 杂草对草甘膦敏感性快速测定方法%Quick Detection Methods of the Sensitivity of Weeds to Glyphosate

    Institute of Scientific and Technical Information of China (English)

    方宇; 倪汉文

    2013-01-01

    [Aims] The method of quickly detecting weed sensitivities to glyphosate was established.[Methods] The reliabilities of the conventional whole-plant method and two quick methods seed bioassay and leaf segment bioassay were compared in detecting weed sensitivities to glyphosate with four weed species Echinochloa crus-galli,Setaria viridis,Amaranthus retroflexus and Abutilon theophrasti.[Results] The sensitivity of these weeds to glyphosate was similar whether using seed and leaf segment detection methods or using the conventional detection method.The order of weed sensitivity to this herbicide was A.theophrasti < E.crus-galli < A.retroflexus < S.viridis.[Conclusions] Seed bioassay and leaf segment bioassay are reliable in detecting sensitivities of weeds to glyphosate.%[目的]建立杂草对草甘膦敏感性的快速检测方法.[方法]比较种子和叶段2种快速测定法和常规整株测定法测定4种杂草对草甘膦的剂量反应的可靠性.[结果]种子和叶段2种快速测定法和常规整株测定法测定的稗草、狗尾草、反枝苋和苘麻4种杂草对草甘膦的敏感性相当,敏感性顺序为苘麻<稗草<反枝苋<狗尾草.[结论]种子和叶段2种快速法测定能可靠地测定杂草对草甘膦的敏感性.

  8. Direct and sensitive determination of glyphosate and aminomethylphosphonic acid in environmental water samples by high performance liquid chromatography coupled to electrospray tandem mass spectrometry.

    Science.gov (United States)

    Guo, Hongyue; Riter, Leah S; Wujcik, Chad E; Armstrong, Daniel W

    2016-04-22

    A novel method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was developed for the sensitive determination of glyphosate and its major degradation product, AMPA in environmental water samples. The method involves the use of MS compatible mobile phases (0.1% formic acid in water and acetonitrile) for HPLC and direct analysis of water samples without sample derivatization. The method has been validated in different types of water matrices (drinking, surface and groundwater) by accuracy and precision studies with samples spiked at 0.1, 7.5 and 90 ppb. All mean accuracy values ranged from 85% to 112% for glyphosate and AMPA using both primary and secondary quantitative ion transitions (RSD ≤ 10%). Moreover, both primary and secondary ion transitions for glyphosate and AMPA can achieve the quantitation limits at 0.1 ppb. The linear dynamic range of the calibration curves were from 0.1 to 100 ppb for each analyte at each ion transitions with correlation coefficient higher than 0.997.

  9. Direct and sensitive determination of glyphosate and aminomethylphosphonic acid in environmental water samples by high performance liquid chromatography coupled to electrospray tandem mass spectrometry.

    Science.gov (United States)

    Guo, Hongyue; Riter, Leah S; Wujcik, Chad E; Armstrong, Daniel W

    2016-04-22

    A novel method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) was developed for the sensitive determination of glyphosate and its major degradation product, AMPA in environmental water samples. The method involves the use of MS compatible mobile phases (0.1% formic acid in water and acetonitrile) for HPLC and direct analysis of water samples without sample derivatization. The method has been validated in different types of water matrices (drinking, surface and groundwater) by accuracy and precision studies with samples spiked at 0.1, 7.5 and 90 ppb. All mean accuracy values ranged from 85% to 112% for glyphosate and AMPA using both primary and secondary quantitative ion transitions (RSD ≤ 10%). Moreover, both primary and secondary ion transitions for glyphosate and AMPA can achieve the quantitation limits at 0.1 ppb. The linear dynamic range of the calibration curves were from 0.1 to 100 ppb for each analyte at each ion transitions with correlation coefficient higher than 0.997. PMID:26993781

  10. 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 μg mL−1 and 28 μg mL−1, with a detection limit of 1.3 × 10−3 μg mL−1 (3δ). 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.

  11. 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.

  12. Measures to reduce glyphosate runoff from hard surfaces, 2: effect of time interval between application and first precipitation event

    NARCIS (Netherlands)

    Luijendijk, C.D.; Beltman, W.H.J.; Smidt, R.A.; Pas, van der L.J.T.; Kempenaar, C.

    2005-01-01

    In this research the effect of moisture conditions of hard surfaces on emission of herbicides from hard surfaces was quantified. In addition the dissipation of glyphosate applied on brick-pavement is determined in time. The outdoor experiment was carried out on 3 and 17 June 2003. In previous resear

  13. Aspectos morfofisiológicos de biótipos de azevém (Lolium multiflorum sensíveis e resistentes ao glyphosate Morphophysiological aspects of ryegrass biotypes (Lolium multiflorum sensitive and resistant to glyphosate

    Directory of Open Access Journals (Sweden)

    J Galvan

    2011-01-01

    Full Text Available O azevém é uma gramínea com elevado potencial de infestação em lavouras e pomares, e seu controle com glyphosate tem sido limitado devido à existência de biótipos resistentes a esse herbicida. Objetivou-se comparar quatro biótipos de azevém coletados em diferentes regiões do Rio Grande do Sul, com o intuito de testar a hipótese de que aspectos morfofisiológicos e fenológicos estejam vinculados à resistência. O experimento foi conduzido em casa de vegetação, onde um biótipo suscetível (B1S, Passo Fundo e três resistentes ao glyphosate (B2R, Santa Maria; B3R, Júlio de Castilhos; e B4R, Vacaria foram colhidos aos 126, 147, 168 e 189 dias de idade. O biótipo B1S mostrou 21 dias de antecipação no florescimento em relação aos demais biótipos. O biótipo B4R produziu significativamente mais folhas (43 por planta, afilhos (14 por planta, espigas (14 por planta, sementes (3.484 por planta e matéria seca total (raízes + parte aérea = 13,8 g por planta. Conclui-se que biótipos sensíveis não podem ser diferidos de biótipos resistentes apenas por aspectos morfológicos relacionados ao vigor.Ryegrass has a high potential for infestation in crops and orchads and its control with glyphosate has been limited due to the existence of herbicide-resistant biotypes. The objective of this work was to compare four ryegrass biotypes collected from different regions in the state of Rio Grande do Sul, Brazil, to test the hypothesis that morphophysiological aspects and phenology are linked to resistance. The experiment was conducted in a greenhouse, where four biotypes, one susceptible (B1S, Passo Fundo and three resistant to glyphosate (B2R, Santa Maria; B3R, Julio de Castillos; B4R, Vacaria were collected at 126, 147, 168 and 189 days of age. Biotype B1S showed 21 days in advance of flowering in relation to the other biotypes. Biotype B4R produced significantly more leaves (43 per plant, tillers (14 per plant, ears (14 per plant, seeds

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

    OpenAIRE

    Mailin Gaupp-Berghausen; Martin Hofer; Boris Rewald; 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...

  15. Fate of glyphosate stored in weed residues and the potential of phytotoxicity for following crops.

    OpenAIRE

    Tesfamariam, Tsehaye; Bott, Sebastian; Roemheld, Volker; Neumann, Guenter

    2009-01-01

    Glyphosate, a broad spectrum, non-selective herbicide, is the world´s most important and widely used herbicide. The globally increasing adoption of no-till or reduced tillage systems is becoming a driving force for enhanced glyphosate use. In such systems, glyphosate is applied pre-sowing for weed control and glyphosate may remain in root and shoot residues. To evaluate potential risks associated with glyphosate residues, a pot experiment was conducted under controlled greenhouse conditions w...

  16. Glyphosate accumulation, translocation, and biological effects in Coffea arabica after single and multiple exposures

    DEFF Research Database (Denmark)

    Schrübbers, Lars Christoph; Valverde, Bernal E.; Strobel, Bjarne W.;

    2016-01-01

    In perennial crops like coffee, glyphosate drift exposure can occur multiple times during its commercial life span. Due to limited glyphosate degradation in higher plants, a potential accumulation of glyphosate could lead to increased biological effects with increased exposure frequency....... In this study, we investigated glyphosate translocation over time, and its concentration and biological effects after single and multiple simulated spray-drift exposures. Additionally, shikimic acid/glyphosate ratios were used as biomarkers for glyphosate binding to its target enzyme.Four weeks after...... the exposure, glyphosate was continuously translocated. Shikimic acid levels were lin-ear correlated with glyphosate levels. After two months, however, glyphosate appeared to have reduced activity. In the greenhouse, multiple applications resulted in higher internal glyphosate concentrations.The time...

  17. Sensitivity analysis via reduced order adjoint method

    International Nuclear Information System (INIS)

    Notwithstanding the voluminous literature on adjoint sensitivity analysis, it has been generally dismissed by practitioners as cumbersome with limited value in realistic engineering models. This perception reflects two limitations about adjoint sensitivity analysis: a) its most effective application is limited to calculation of first-order variations; when higher order derivatives are required, it quickly becomes computationally inefficient; and b) the number of adjoint model evaluations depends on the number of responses, which renders it ineffective for multi-physics model where entire distributions, such as flux and power distribution, are often transferred between the various physics models. To overcome these challenges, this manuscript employs recent advances in reduced order modeling to re-cast the adjoint model equations into a form that renders its application to real reactor models practical. Past work applied reduced order modeling techniques to render reduction for general nonlinear high dimensional models by identifying mathematical subspaces, called active subspaces, that capture all dominant features of the model, including both linear and nonlinear variations. We demonstrate the application of these techniques to the calculation of first-order derivatives, or as commonly known sensitivity coefficients, for a fuel assembly model with many responses. We show that the computational cost becomes dependent on the physics model itself, via the so-called rank of the active subspace, rather than the number of responses or parameters. (author)

  18. Target and Non-target Site Mechanisms Developed by Glyphosate-Resistant Hairy beggarticks (Bidens pilosa L.) Populations from Mexico

    Science.gov (United States)

    Alcántara-de la Cruz, Ricardo; Fernández-Moreno, Pablo T.; Ozuna, Carmen V.; Rojano-Delgado, Antonia M.; Cruz-Hipolito, Hugo E.; Domínguez-Valenzuela, José A.; Barro, Francisco; De Prado, Rafael

    2016-01-01

    In 2014 hairy beggarticks (Bidens pilosa L.) has been identified as being glyphosate-resistant in citrus orchards from Mexico. The target and non-target site mechanisms involved in the response to glyphosate of two resistant populations (R1 and R2) and one susceptible (S) were studied. Experiments of dose-response, shikimic acid accumulation, uptake-translocation, enzyme activity and 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS) gene sequencing were carried out in each population. The R1 and R2 populations were 20.4 and 2.8-fold less glyphosate sensitive, respectively, than the S population. The resistant populations showed a lesser shikimic acid accumulation than the S population. In the latter one, 24.9% of 14C-glyphosate was translocated to the roots at 96 h after treatment; in the R1 and R2 populations only 12.9 and 15.5%, respectively, was translocated. Qualitative results confirmed the reduced 14C-glyphosate translocation in the resistant populations. The EPSPS enzyme activity of the S population was 128.4 and 8.5-fold higher than the R1 and R2 populations of glyphosate-treated plants, respectively. A single (Pro-106-Ser), and a double (Thr-102-Ile followed by Pro-106-Ser) mutations were identified in the EPSPS2 gene conferred high resistance in R1 population. Target-site mutations associated with a reduced translocation were responsible for the higher glyphosate resistance in the R1 population. The low-intermediate resistance of the R2 population was mediated by reduced translocation. This is the first glyphosate resistance case confirmed in hairy beggarticks in the world. PMID:27752259

  19. Oral bioavailability of glyphosate: studies using two intestinal cell lines.

    Science.gov (United States)

    Vasiluk, Luba; Pinto, Linda J; Moore, Margo M

    2005-01-01

    Glyphosate is a commonly used nonselective herbicide that inhibits plant growth through interference with the production of essential aromatic amino acids. In vivo studies in mammals with radiolabeled glyphosate have shown that 34% of radioactivity was associated with intestinal tissue 2 h after oral administration. The aim of our research was to investigate the transport, binding, and toxicity of glyphosate to the cultured human intestinal epithelial cell line, Caco-2, and the rat small intestinal crypt-derived cell line, ileum epithelial cells-18 (IEC-18). An in vitro analysis of the transport kinetics of [14C]-glyphosate showed that 4 h after exposure, approximately 8% of radiolabeled glyphosate moved through the Caco-2 monolayer in a dose-dependent manner. Binding of glyphosate to cells was saturable and approximately 4 x 10(11) binding sites/cell were estimated from bound [14C]. Exposure of Caco-2 cells to > or =10 mg/ml glyphosate reduced transmembrane electrical resistance (TEER) by 82 to 96% and increased permeability to [3H]-mannitol, indicating that paracellular permeability increased in glyphosate-treated cells. At 10-mg/ml glyphosate, both IEC-18 and Caco-2 cells showed disruption in the actin cytoskeleton. In Caco-2 cells, significant lactate dehydrogenase leakage was observed when cells were exposed to 15 mg/ml of glyphosate. These data indicate that at doses >10 mg/ml, glyphosate significantly disrupts the barrier properties of cultured intestinal cells.

  20. Phosphate fertilizer impacts on glyphosate sorption by soil.

    Science.gov (United States)

    Munira, Sirajum; Farenhorst, Annemieke; Flaten, Don; Grant, Cynthia

    2016-06-01

    This research examined the impact of field-aged phosphate and cadmium (Cd) concentrations, and fresh phosphate co-applications, on glyphosate sorption by soil. Soil samples were collected in 2013 from research plots that had received, from 2002 to 2009, annual applications of mono ammonium phosphate (MAP) at 20, 40 and 80 kg P ha(-1) and from products containing 0.4, 70 or 210 mg Cd kg(-1) as an impurity. A series of batch equilibrium experiments were carried out to quantify the glyphosate sorption distribution constant, Kd. Extractable Cd concentrations in soil had no significant effect on glyphosate sorption. Glyphosate Kd values significantly decreased with increasing Olsen-P concentrations in soil, regardless of the pH conditions studied. Experiments repeated with a commercially available glyphosate formulation showed statistically similar results as the experiments performed with analytical-grade glyphosate. Co-applications of MAP with glyphosate also reduced the available sorption sites to retain glyphosate, but less so when soils already contain large amounts of phosphate. Glyphosate Kd values in soils ranged from 173 to 939 L kg(-1) under very strong to strongly acidic condition but the Kd was always glyphosate may become mobile by water in soils with high phosphate levels. Otherwise, glyphosate residues in agricultural soils are more likely to be transported off-site by wind and water-eroded sediments than by leaching or runoff. PMID:27035384

  1. Phosphate fertilizer impacts on glyphosate sorption by soil.

    Science.gov (United States)

    Munira, Sirajum; Farenhorst, Annemieke; Flaten, Don; Grant, Cynthia

    2016-06-01

    This research examined the impact of field-aged phosphate and cadmium (Cd) concentrations, and fresh phosphate co-applications, on glyphosate sorption by soil. Soil samples were collected in 2013 from research plots that had received, from 2002 to 2009, annual applications of mono ammonium phosphate (MAP) at 20, 40 and 80 kg P ha(-1) and from products containing 0.4, 70 or 210 mg Cd kg(-1) as an impurity. A series of batch equilibrium experiments were carried out to quantify the glyphosate sorption distribution constant, Kd. Extractable Cd concentrations in soil had no significant effect on glyphosate sorption. Glyphosate Kd values significantly decreased with increasing Olsen-P concentrations in soil, regardless of the pH conditions studied. Experiments repeated with a commercially available glyphosate formulation showed statistically similar results as the experiments performed with analytical-grade glyphosate. Co-applications of MAP with glyphosate also reduced the available sorption sites to retain glyphosate, but less so when soils already contain large amounts of phosphate. Glyphosate Kd values in soils ranged from 173 to 939 L kg(-1) under very strong to strongly acidic condition but the Kd was always glyphosate may become mobile by water in soils with high phosphate levels. Otherwise, glyphosate residues in agricultural soils are more likely to be transported off-site by wind and water-eroded sediments than by leaching or runoff.

  2. Glyphosate-resistant and glyphosate-susceptible Palmer amaranth (Amaranthus palmeri S Wats.): hyperspectral reflectance properties of plants and potential for classification

    Science.gov (United States)

    BACKGROUND: Palmer amaranth (Amaranthus palmeri S. Wats.) is a troublesome agronomic weed in the southern United States, and several populations have evolved resistance to glyphosate. This paper reports spectral signatures of glyphosate-resistant (GR) and glyphosate-sensitive (GS) plants, and explor...

  3. 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

  4. 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

    Directory of Open Access Journals (Sweden)

    M. Yanniccari

    2012-03-01

    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.

  5. 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...

  6. Physiology of Glyphosate-Resistant and Glyphosate-Susceptible Palmer Amaranth (Amaranthus palmeri) Biotypes Collected from North Carolina

    OpenAIRE

    Jared R. Whitaker; James D. Burton; Alan C. York; Jordan, David L.; Aman Chandi

    2013-01-01

    Glyphosate-resistant (GR) biotypes of Palmer amaranth are now commonly found across the southern United States. Experiments were conducted to characterize physiological differences between a GR biotype and a glyphosate-susceptible (GS) biotype from North Carolina. The GR biotype had an 18-fold level of resistance based upon rates necessary to reduce shoot fresh weight 50%. Shikimate accumulated in both biotypes following glyphosate application, but greater concentrations were found in GS plan...

  7. Impact of glyphosate resistant corn, glyphosate applications, and tillage on soil nutrient ratios, exoenzyme activities, and nutrient acquisition ratios

    Science.gov (United States)

    We report results of the last two years of a 7-year (2008-2014) field experiment designed to test the null hypothesis that applications of glyphosate on glyphosate resistant corn (Zea mays L.) as a routine weed control practice under both conventional and reduced tillage practices would have no effe...

  8. 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.

  9. Sensitivity to glyphosate and dynamics of shikimate accumulation in three weed species following glyphosate application%三种杂草对草甘膦的敏感性及处理后植株体内莽草酸积累量差异

    Institute of Scientific and Technical Information of China (English)

    陈景超; 张朝贤; 黄红娟; 魏守辉; 张猛; 郭峰

    2011-01-01

    为明确不同杂草对草甘膦的敏感性,以稗Echinochloa crusgalli、马唐Digitaria sanguinalis、藜Chenopodium album为供试材料,采用生物测定法和吸光光度法分别测定了草甘膦对3种杂草的抑制中浓度( GR50),以及不同剂量处理后杂草体内莽草酸积累量的变化.经410 g/hm2(有效成分)的草甘膦处理后,稗体内莽草酸积累量呈上升-下降-上升趋势,而马唐和藜则表现为缓慢上升,根据此剂量处理下莽草酸积累趋势得出,3种杂草对草甘膦的敏感性由高到低依次为稗、藜和马唐,与生测法的结果一致.经820 ~3 280 g/hm2(有效成分)的草甘膦处理后,3种杂草体内莽草酸积累量从第2d开始急剧升高,增长速率随着草甘膦处理剂量的增加而加大;处理后稗、马唐和藜体内莽草酸积累量最高值差异显著,分别为1 137.9、4 989.7和2 084.2 μg/g,为各自对照水平的16.7、23.7和82.9倍.该研究结果可为系统检测杂草对草甘膦的敏感性提供依据.%The GR50 value and shikimate accumulation in three problematic weed species were determined by whole plant bioassay and spectrophotometric assay, respectively, after treated by glyphosate. After treated by glyphosate at 410 g (a. I. )/ha, shikimate accumulation in Echinochloa crusgalli was first increased, then declined, increased slightly finally. However, it kept increasing in Chenopodium album and Digitaria sanguinalis. Based on the accumulation of shikimate by glyphosate treated within this dosage, the order of sensitivity to glyphosate from high to low was E. Crusgalli, C. Album and D. Sanguinalis, which was similar to the result of whole plant bioassay. Shikimate accumulation was increased rapidly in all three weeds after treated 2 days by glyphosate within the dose range of 820 to 3 280 g(a. I. )/ha, and the accumulation rate showed positive relationship to the treatment dosage. The highest shikimate accumulation in E. Crusgalli,D. Sanguinalis and C

  10. Comparison of Nitrogen Fertilizers, Induce and Zinc Addition on Glyphosate Efficacy on Three Different Weed Species.

    Directory of Open Access Journals (Sweden)

    Hussein F. Abouziena

    2014-05-01

    Full Text Available Herbicides are often tank-mixed with fertilizers to save time, labour, energy, and equipment costs. However addition of some additives with glyphosate may result in reducing glyphosate efficacy. Therefore we evaluated the potential of three nitrogen sources (ammonium sulphate (AMS at 2 or 4% w/v, ammonium nitrate (AN at 1 or 2% w/v, urea at 1 or 2 % w/v, nonionic adjuvant (Induce at 0.05% v/v and Zn at 250 g Zn/ha (1321 ppm to enhance glyphosate efficacy on pig weed (Amaranthus retroflexus L., crowfoot grass (Dactyloctenium egyptium L. and yellow nutsedge (Cyperus esculentus L. under greenhouse conditions. The results indicated that there were variations in susceptibility of the three weeds to glyphosate+adjuvant treatments. Addition of AN at 2% reduced the efficacy of glyphosate on crowfoot grass. There was an antagonistic effect between glyphosate herbicide and Zn; the phytotoxic effect of glyphosate on the three weeds was less than 50 %. Zinc tank-mixed with glyphosate resulted in a greater number of tubers and shoots per plant than the untreatedol. Addition of AN or urea at 2% reduced glyphosate efficacy by about 2.3 and 9 %, respectively, relative to their addition at 1%. Tankmixes of urea (1%, AN (1%, AMS (2% and Induce adjuvant (0.05% generally enhanced the efficacy of glyphosate (0.85 kg/ha, whereas the addition of Zn, as zinc sulphate, to glyphosate sprays adversely affected herbicide efficacy.

  11. 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.

  12. 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)

  13. Tolerance and accumulation of shikimic acid in response to glyphosate applications in glyphosate-resistant and nonglyphosate-resistant cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Pline, Wendy A; Wilcut, John W; Duke, Stephen O; Edmisten, Keith L; Wells, Randy

    2002-01-30

    Measurement of shikimic acid accumulation in response to glyphosate inhibition of 5-enolpyruvylshikimate-3-phosphate synthase is a rapid and accurate assay to quantify glyphosate-induced damage in sensitive plants. Two methods of assaying shikimic acid, a spectrophotometric and a high-performance liquid chromatography (HPLC) method, were compared for their accuracy of recovering known amounts of shikimic acid spiked into plant samples. The HPLC method recovered essentially 100% of shikimic acid as compared with only 73% using the spectrophotometric method. Relative sensitivity to glyphosate was measured in glyphosate-resistant (GR) and non-GR cotton leaves, fruiting branches, and squares (floral buds) by assaying shikimic acid. Accumulation of shikimic acid was not observed in any tissue, either GR or non-GR, at rates of 5 mM glyphosate or less applied to leaves. All tissues of non-GR plants accumulated shikimic acid in response to glyphosate treatment; however, only fruiting branches and squares of GR plants accumulated a slight amount of shikimic acid. In non-GR cotton, fruiting branches and squares accumulated 18 and 11 times, respectively, more shikimic acid per micromolar of translocated glyphosate than leaf tissue, suggesting increased sensitivity to glyphosate of reproductive tissue over vegetative tissue. GR cotton leaves treated with 80 mM of glyphosate accumulated 57 times less shikimic acid per micromolar of translocated glyphosate than non-GR cotton but only 12.4- and 4-fold less in fruiting branches and squares, respectively. The increased sensitivity of reproductive structures to glyphosate inhibition may be due to a higher demand for shikimate pathway products and may provide an explanation for reports of fruit abortion from glyphosate-treated GR cotton.

  14. Effects of glyphosate on the mineral content of glyphosate-resistant soybeans (Glycine max).

    Science.gov (United States)

    Duke, Stephen O; Reddy, Krishna N; Bu, Kaixuan; Cizdziel, James V

    2012-07-11

    There are conflicting claims as to whether treatment with glyphosate adversely affects mineral nutrition of glyphosate-resistant (GR) crops. Those who have made claims of adverse effects have argued links between reduced Mn and diseases in these crops. This article describes experiments designed to determine the effects of a recommended rate (0.86 kg ha(-1)) of glyphosate applied once or twice on the mineral content of young and mature leaves, as well as in seeds produced by GR soybeans (Glycine max) in both the greenhouse and field using inductively coupled plasma mass spectrometry (ICP-MS). In the greenhouse, there were no effects of either one application (at 3 weeks after planting, WAP) or two applications (at 3 and 6 WAP) of glyphosate on Ca, Mg, Mn, Zn, Fe, Cu, Sr, Ba, Al, Cd, Cr, Co, or Ni content of young or old leaves sampled at 6, 9, and 12 WAP and in harvested seed. Se concentrations were too low for accurate detection in leaves, but there was also no effect of glyphosate applications on Se in the seeds. In the field study, there were no effects of two applications (at 3 and 6 WAP) of glyphosate on Ca, Mg, Mn, Zn, Fe, Cu, Sr, Ba, Al, Cd, Cr, Co, or Ni content of young or old leaves at either 9 or 12 WAP. There was also no effect on Se in the seeds. There was no difference in yield between control and glyphosate-treated GR soybeans in the field. The results indicate that glyphosate does not influence mineral nutrition of GR soybean at recommended rates for weed management in the field. Furthermore, the field studies confirm the results of greenhouse studies.

  15. Foliar nickel application alleviates detrimental effects of glyphosate drift on yield and seed quality of wheat.

    Science.gov (United States)

    Kutman, Bahar Yildiz; Kutman, Umit Baris; Cakmak, Ismail

    2013-09-01

    Glyphosate drift to nontarget crops causes growth aberrations and yield losses. This herbicide can also interact with divalent nutrients and form poorly soluble complexes. The possibility of using nickel (Ni), an essential divalent metal, for alleviating glyphosate drift damage to wheat was investigated in this study. Effects of Ni applications on various growth parameters, seed yield, and quality of durum wheat ( Triticum durum ) treated with sublethal glyphosate at different developmental stages were investigated in greenhouse experiments. Nickel concentrations of various plant parts and glyphosate-induced shikimate accumulation were measured. Foliar but not soil Ni applications significantly reduced glyphosate injuries including yield losses, stunting, and excessive tillering. Both shoot and grain Ni concentrations were enhanced by foliar Ni treatment. Seed germination and seedling vigor were impaired by glyphosate and improved by foliar Ni application to parental plants. Foliar Ni application appears to have a great potential to ameliorate glyphosate drift injury to wheat.

  16. Bacterial glyphosate resistance conferred by overexpression of an E. coli membrane efflux transporter.

    Science.gov (United States)

    Staub, Jeffrey M; Brand, Leslie; Tran, Minhtien; Kong, Yifei; Rogers, Stephen G

    2012-04-01

    Glyphosate herbicide-resistant crop plants, introduced commercially in 1994, now represent approximately 85% of the land area devoted to transgenic crops. Herbicide resistance in commercial glyphosate-resistant crops is due to expression of a variant form of a bacterial 5-enolpyruvylshikimate-3-phosphate synthase with a significantly decreased binding affinity for glyphosate at the target site of the enzyme. As a result of widespread and recurrent glyphosate use, often as the only herbicide used for weed management, increasing numbers of weedy species have evolved resistance to glyphosate. Weed resistance is most often due to changes in herbicide translocation patterns, presumed to be through the activity of an as yet unidentified membrane transporter in plants. To provide insight into glyphosate resistance mechanisms and identify a potential glyphosate transporter, we screened Escherichia coli genomic DNA for alternate sources of glyphosate resistance genes. Our search identified a single non-target gene that, when overexpressed in E. coli and Pseudomonas, confers high-level glyphosate resistance. The gene, yhhS, encodes a predicted membrane transporter of the major facilitator superfamily involved in drug efflux. We report here that an alternative mode of glyphosate resistance in E. coli is due to reduced accumulation of glyphosate in cells that overexpress this membrane transporter and discuss the implications for potential alternative resistance mechanisms in other organisms such as plants.

  17. Inhibition effect of glyphosate on the acute and subacute toxicity of cadmium to earthworm Eisenia fetida.

    Science.gov (United States)

    Zhou, Chui-Fan; Wang, Yu-Jun; Sun, Rui-Juan; Liu, Cun; Fan, Guang-Ping; Qin, Wen-Xiu; Li, Cheng-Cheng; Zhou, Dong-Mei

    2014-10-01

    The acute and subacute toxicities of cadmium (Cd) to earthworm Eisenia fetida in the presence and absence of glyphosate were studied. Although Cd is highly toxic to E. fetida, the presence of glyphosate markedly reduced the acute toxicity of Cd to earthworm; both the mortality rate of the earthworms and the accumulation of Cd decreased with the increase of the glyphosate/Cd molar ratio. The subcellular distribution of Cd in E. fetida tissues showed that internal Cd was dominant in the intact cells fraction and the heat-stable proteins fraction. The presence of glyphosate reduced the concentration of Cd in all fractions, especially the intact cells. During a longer period of exposure, the weight loss of earthworm and the total Cd absorption was alleviated by glyphosate. Thus, the herbicide glyphosate can reduce the toxicity and bioavailability of Cd in the soil ecosystems at both short- and long-term exposures.

  18. Vacuolar glyphosate-sequestration correlates with glyphosate resistance in ryegrass (Lolium spp.) from Australia, South America, and Europe: a 31P NMR investigation.

    Science.gov (United States)

    Ge, Xia; d'Avignon, D André; Ackerman, Joseph J H; Collavo, Alberto; Sattin, Maurizio; Ostrander, Elizabeth L; Hall, Erin L; Sammons, R Douglas; Preston, Christopher

    2012-02-01

    Lolium spp., ryegrass, variants from Australia, Brazil, Chile, and Italy showing differing levels of glyphosate resistance were examined by (31)P NMR. Extents of glyphosate (i) resistance (LD(50)), (ii) inhibition of 5-enopyruvyl-shikimate-3-phosphate synthase (EPSPS) activity (IC(50)), and (iii) translocation were quantified for glyphosate-resistant (GR) and glyphosate-sensitive (GS) Lolium multiflorum Lam. variants from Chile and Brazil. For comparison, LD(50) and IC(50) data for Lolium rigidum Gaudin variants from Italy were also analyzed. All variants showed similar cellular uptake of glyphosate by (31)P NMR. All GR variants showed glyphosate sequestration within the cell vacuole, whereas there was minimal or no vacuole sequestration in the GS variants. The extent of vacuole sequestration correlated qualitatively with the level of resistance. Previous (31)P NMR studies of horseweed ( Conyza canadensis (L.) Cronquist) revealed that glyphosate sequestration imparted glyphosate resistance. Data presented herein suggest that glyphosate vacuolar sequestration is strongly contributing, if not the major contributing, resistance mechanism in ryegrass as well.

  19. Functional characterization of aroA from Rhizobium leguminosarum with significant glyphosate tolerance in transgenic Arabidopsis.

    Science.gov (United States)

    Han, Jing; Tian, Yong-Sheng; Xu, Jing; Wang, Li-Juan; Wang, Bo; Peng, Ri-He; Yao, Quan-Hong

    2014-09-01

    Glyphosate is the active component of the top-selling herbicide, the phytotoxicity of which is due to its inhibition of the shikimic acid pathway. 5-Enolpyruvylshikimate-3-phosphate synthase (EPSPS) is a key enzyme in the shikimic acid pathway. Glyphosate tolerance in plants can be achieved by the expression of a glyphosate-insensitive aroA gene (EPSPS). In this study, we used a PCR-based two-step DNA synthesis method to synthesize a new aroA gene (aroAR. leguminosarum) from Rhizobium leguminosarum. In vitro glyphosate sensitivity assays showed that aroAR. leguminosarum is glyphosate tolerant. The new gene was then expressed in E. coli and key kinetic values of the purified enzyme were determined. Furthermore, we transformed the aroA gene into Arabidopsis thaliana by the floral dip method. Transgenic Arabidopsis with the aroAR. leguminosarum gene was obtained to prove its potential use in developing glyphosate-resistant crops.

  20. Physiology of Glyphosate-Resistant and Glyphosate-Susceptible Palmer Amaranth (Amaranthus palmeri Biotypes Collected from North Carolina

    Directory of Open Access Journals (Sweden)

    Jared R. Whitaker

    2013-01-01

    Full Text Available Glyphosate-resistant (GR biotypes of Palmer amaranth are now commonly found across the southern United States. Experiments were conducted to characterize physiological differences between a GR biotype and a glyphosate-susceptible (GS biotype from North Carolina. The GR biotype had an 18-fold level of resistance based upon rates necessary to reduce shoot fresh weight 50%. Shikimate accumulated in both biotypes following glyphosate application, but greater concentrations were found in GS plants. Absorption and translocation of 14C-glyphosate were studied in both biotypes with and without an overspray with commercial glyphosate potassium salt (840 g ae ha−1 immediately prior to 14C-glyphosate application. Greater absorption was noted 6 h after treatment (HAT in GS compared with GR plants, but no differences were observed at 12 to 72 HAT. Oversprayed plants absorbed 33 and 61% more 14C by 48 and 72 HAT, respectively, than plants not oversprayed. 14C distribution (above treated leaf, below treated leaf, roots was similar in both biotypes. Together, these results suggest that resistance in this biotype is not due to an altered target enzyme or translocation but may be in part due to the rate of glyphosate absorption. These results also are consistent with resistance being due to increased gene copy number for the target enzyme.

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

    Science.gov (United States)

    Sanders, Tina; Lassen, Stephan

    2015-04-01

    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.

  2. Spray droplet size, drift potential, and risks to nontarget organisms from aerially applied glyphosate for coca control in Colombia.

    Science.gov (United States)

    Hewitt, Andrew J; Solomon, Keith R; Marshall, E J P

    2009-01-01

    A wind tunnel atomization study was conducted to measure the emission droplet size spectra for water and Glyphos (a glyphosate formulation sold in Colombia) + Cosmo-flux sprays for aerial application to control coca and poppy crops in Colombia. The droplet size spectra were measured in a wind tunnel for an Accu-Flo nozzle (with 16 size 0.085 [2.16 mm] orifices), under appropriate simulated aircraft speeds (up to 333 km/h), using a laser diffraction instrument covering a dynamic size range for droplets of 0.5 to 3,500 microm. The spray drift potential of the glyphosate was modeled using the AGDISP spray application and drift model, using input parameters representative of those occurring in Colombia for typical aerial application operations. The droplet size spectra for tank mixes containing glyphosate and Cosmo-Flux were considerably finer than water and became finer with higher aircraft speeds. The tank mix with 44% glyphosate had a D(v0.5) of 128 microm, while the value at the 4.9% glyphosate rate was 140 microm. These are classified as very fine to fine sprays. Despite being relatively fine, modeling showed that the droplets would not evaporate as rapidly as most similarly sized agricultural sprays because the nonvolatile proportion of the tank mix (active and inert adjuvant ingredients) was large. Thus, longer range drift is small and most drift that does occur will deposit relatively close to the application area. Drift will only occur downwind and, with winds of velocity less than the modeled maximum of 9 km/h, the drift distance would be substantially reduced. Spray drift potential might be additionally reduced through various practices such as the selection of nozzles, tank mix adjuvants, aircraft speeds, and spray pressures that would produce coarser sprays. Species sensitivity distributions to glyphosate were constructed for plants and amphibians. Based on modeled drift and 5th centile concentrations, appropriate no-spray buffer zones (distance from the

  3. Investigating the Mechanism of Glyphosate Resistance in Rigid Ryegrass (Lolium rigidum)

    Science.gov (United States)

    Glyphosate is a broad-spectrum herbicide that has been used extensively for more than 20 yr. The first glyphosate-resistant weed biotype appeared in 1996; it involved a rigid ryegrass population from Australia that exhibited an LD50 value approximately 10-fold higher than that of sensitive biotypes....

  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.

  5. Differential effects of glyphosate and aminomethylphosphonic acid (AMPA) on photosynthesis and chlorophyll metabolism in willow plants.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; Le Manac'h, Sarah Gingras; Maccario, Sophie; Labrecque, Michel; Lucotte, Marc; Juneau, Philippe

    2016-06-01

    We used a willow species (Salix miyabeana cultivar SX64) to examine the differential secondary-effects of glyphosate and aminomethylphosphonic acid (AMPA), the principal glyphosate by-product, on chlorophyll metabolism and photosynthesis. Willow plants were treated with different concentrations of glyphosate (equivalent to 0, 1.4, 2.1 and 2.8kgha(-1)) and AMPA (equivalent to 0, 0.28, 1.4 and 2.8kgha(-1)) and evaluations of pigment contents, chlorophyll fluorescence, and oxidative stress markers (hydrogen peroxide content and antioxidant enzyme activities) in leaves were performed after 12h of exposure. We observed that AMPA and glyphosate trigger different mechanisms leading to decreases in chlorophyll content and photosynthesis rates in willow plants. Both chemicals induced ROS accumulation in willow leaves although only glyphosate-induced oxidative damage through lipid peroxidation. By disturbing chlorophyll biosynthesis, AMPA induced decreases in chlorophyll contents, with consequent effects on photosynthesis. With glyphosate, ROS increases were higher than the ROS-sensitive threshold, provoking chlorophyll degradation (as seen by pheophytin accumulation) and invariable decreases in photosynthesis. Peroxide accumulation in both AMPA and glyphosate-treated plants was due to the inhibition of antioxidant enzyme activities. The different effects of glyphosate on chlorophyll contents and photosynthesis as described in the literature may be due to various glyphosate:AMPA ratios in those plants. PMID:27155486

  6. Differential effects of glyphosate and aminomethylphosphonic acid (AMPA) on photosynthesis and chlorophyll metabolism in willow plants.

    Science.gov (United States)

    Gomes, Marcelo Pedrosa; Le Manac'h, Sarah Gingras; Maccario, Sophie; Labrecque, Michel; Lucotte, Marc; Juneau, Philippe

    2016-06-01

    We used a willow species (Salix miyabeana cultivar SX64) to examine the differential secondary-effects of glyphosate and aminomethylphosphonic acid (AMPA), the principal glyphosate by-product, on chlorophyll metabolism and photosynthesis. Willow plants were treated with different concentrations of glyphosate (equivalent to 0, 1.4, 2.1 and 2.8kgha(-1)) and AMPA (equivalent to 0, 0.28, 1.4 and 2.8kgha(-1)) and evaluations of pigment contents, chlorophyll fluorescence, and oxidative stress markers (hydrogen peroxide content and antioxidant enzyme activities) in leaves were performed after 12h of exposure. We observed that AMPA and glyphosate trigger different mechanisms leading to decreases in chlorophyll content and photosynthesis rates in willow plants. Both chemicals induced ROS accumulation in willow leaves although only glyphosate-induced oxidative damage through lipid peroxidation. By disturbing chlorophyll biosynthesis, AMPA induced decreases in chlorophyll contents, with consequent effects on photosynthesis. With glyphosate, ROS increases were higher than the ROS-sensitive threshold, provoking chlorophyll degradation (as seen by pheophytin accumulation) and invariable decreases in photosynthesis. Peroxide accumulation in both AMPA and glyphosate-treated plants was due to the inhibition of antioxidant enzyme activities. The different effects of glyphosate on chlorophyll contents and photosynthesis as described in the literature may be due to various glyphosate:AMPA ratios in those plants.

  7. Sintomas da intoxicação inicial de Eucalyptus proporcionados por subdoses de glyphosate aplicadas no caule ou nas folhas Initial symptoms of Eucalyptus intoxication by glyphosate rates applied on the stem or leaves

    Directory of Open Access Journals (Sweden)

    T.P Salgado

    2011-12-01

    herbicide volumes were applied on the stem. In the first one, a glyphosate solution of 3% (v/v was applied at the volumes 0, 1, 5, 10, 20, 40, 80 and 160 µL solution per plant, and in the second, glyphosate solution of 2% (v/v was applied at volumes 0, 1, 5, 15, 30, 60, 90, 120 and 150 µL solution per plant. In assays 3 and 4, glyphosate was sprayed on the plants. The rates in the third assay were: 0, 7.2 10-7, 7.2 10-6, 7.2 10-5, 7.2 10-4, 7.2 10-3, 7.2 10-2, 7.2 10-1, 7.2, 72, 360 and 720 g a.e. of glyphosate ha 1, and in the fourth assay, the rates were: 0, 9, 18, 36, 72, 144, 288, 432, 576, 720, 1.080, 1.440 and 2.160 g a.e. of glyphosate ha-1. All assays were arranged in a randomized design, with three replications. Height, leaf area, and dry mass of the leaves and stem were evaluated in the plants and the results were submitted to regression analysis. When applied on the stem, doses of 40.78 and 51.41 µL per plant of glyphosate solution, 3 and 2% (v/v, respectively, were sufficient to reduce eucalyptus development in 50%. When applied on the plants, more developed plants showed greater sensitivity.Rates of 277.4 and 143.3 g a.e. ha-1 reduced eucalyptus growth in 50%, in assays 3 and 4, respectively.

  8. Carbon-14-glyphosate behavior in relationship to pedoclimatic conditions and crop sequence.

    Science.gov (United States)

    Rampoldi, E Ariel; Hang, Susana; Barriuso, Enrique

    2014-03-01

    The recognition of glyphosate [(-phosphonomethyl) glycine] behavioral patterns can be readily examined using a pedoclimatic gradient. In the present study, glyphosate adsorption-desorption and degradation were examined under different scenarios in relationship to soil properties and soil use applications. Three sites with varied pedoclimatic conditions and two crop sequences were selected. Adsorption-desorption and glyphosate distribution in mineralized, extractable, and nonextractable fractions were assessed under laboratory conditions. Glyphosate sorption was characterized by isotherms and glyphosate degradation using the distribution of C-glyphosate radioactivity among mineralized fractions, two extractable fractions (in water, ER1; in NHOH, ER2), and nonextractable fractions. Results showed sorption indices (distribution coefficient and Freundlich sorption coefficient : 13.4 ± 0.3-64.1 ± 0.9 L kg and 16.2-60.6, respectively), and hysteresis increased among soil sites associated with decreasing soil particle size glyphosate adsorption and decreased hysteresis desorption relative to soils under rotation. To our knowledge, these results are the first to demonstrate that soils with identical properties exhibited different glyphosate retention capacities based on crop sequence. We propose possible explanations for this observation. Our results suggested that characterization of the variability in soil property gradients can serve to determine glyphosate behavioral patterns, which can establish a criterion for use in reducing potential environmental risks.

  9. Glyphosate effect on shikimate, nitrate reductase activity, yield, and seed composition in corn.

    Science.gov (United States)

    Reddy, Krishna N; Bellaloui, Nacer; Zablotowicz, Robert M

    2010-03-24

    When glyphosate is applied to glyphosate-resistant (GR) crops, drift to nonglyphosate-resistant (non-GR) crops may cause significant injury and reduce yields. Tools are needed to quantify injury and predict crop losses. In this study, glyphosate drift was simulated by direct application at 12.5% of the recommended label rate to non-GR corn (Zea mays L.) at 3 or 6 weeks after planting (WAP) during two field seasons in the Mississippi delta region of the southeastern USA. Visual plant injury, shikimate accumulation, nitrate reductase activity, leaf nitrogen, yield, and seed composition were evaluated. Effects were also evaluated in GR corn and GR corn with stacked glufosinate-resistant gene at the recommended label rate at 3 and 6 WAP. Glyphosate at 105 g ae/ha was applied once at 3 or 6 weeks after planting to non-GR corn. Glyphosate at 840 (lower label limit) or 1260 (upper label limit) g ae/ha was applied twice at 3 and 6 WAP to transgenic corn. Glyphosate caused injury (45-55%) and increased shikimate levels (24-86%) in non-GR compared to nontreated corn. In non-GR corn, glyphosate drift did not affect starch content but increased seed protein 8-21% while reducing leaf nitrogen reductase activity 46-64%, leaf nitrogen 7-16%, grain yield 49-54%, and seed oil 18-23%. In GR and GR stacked with glufosinate-resistant corn, glyphosate applied at label rates did not affect corn yield, leaf and seed nitrogen, or seed composition (protein, oil, and starch content). Yet, nitrate reductase activity was reduced 5-19% with glyphosate at 840 + 840 g/ha rate and 8-42% with glyphosate at 1260 + 1260 g/ha rate in both GR and GR stacked corn. These results demonstrate the potential for severe yield loss in non-GR corn exposed to glyphosate drift.

  10. Isoflavone, glyphosate, and aminomethylphosphonic acid levels in seeds of glyphosate-treated, glyphosate-resistant soybean.

    Science.gov (United States)

    Duke, Stephen O; Rimando, Agnes M; Pace, Patrick F; Reddy, Krishna N; Smeda, Reid J

    2003-01-01

    The estrogenic isoflavones of soybeans and their glycosides are products of the shikimate pathway, the target pathway of glyphosate. This study tested the hypothesis that nonphytotoxic levels of glyphosate and other herbicides known to affect phenolic compound biosynthesis might influence levels of these nutraceutical compounds in glyphosate-resistant soybeans. The effects of glyphosate and other herbicides were determined on estrogenic isoflavones and shikimate in glyphosate-resistant soybeans from identical experiments conducted on different cultivars in Mississippi and Missouri. Four commonly used herbicide treatments were compared to a hand-weeded control. The herbicide treatments were (1) glyphosate at 1260 g/ha at 3 weeks after planting (WAP), followed by glyphosate at 840 g/ha at 6 WAP; (2) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied preemergence (PRE), followed by glyphosate at 1260 g/ha at 6 WAP; (3) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied PRE, followed by glyphosate at 1260 g/ha at full bloom; and (4) sulfentrazone at 168 g/ha plus chlorimuron at 34 g/ha applied PRE, followed by acifluorfen at 280 g/ha plus bentazon at 560 g/ha plus clethodim at 140 g/ha at 6 WAP. Soybeans were harvested at maturity, and seeds were analyzed for daidzein, daidzin, genistein, genistin, glycitin, glycitein, shikimate, glyphosate, and the glyphosate degradation product, aminomethylphosphonic acid (AMPA). There were no remarkable effects of any treatment on the contents of any of the biosynthetic compounds in soybean seed from either test site, indicating that early and later season applications of glyphosate have no effects on phytoestrogen levels in glyphosate-resistant soybeans. Glyphosate and AMPA residues were higher in seeds from treatment 3 than from the other two treatments in which glyphosate was used earlier. Intermediate levels were found in treatments 1 and 2. Low levels of glyphosate and AMPA were found in treatment 4 and a

  11. GLYPHOSATE AND GLYPHOSATE-RESISTANT CROP INTERACTIONS WITH RHIZOSPHERE MICROORGANISMS

    Science.gov (United States)

    Glyphosate and glyphosate-resistant crops represent a major advancement in effective weed management that is now widely used in many crop production systems. Studies conducted during 1997-2007 showed that Fusarium root colonization was consistently higher on Roundup Ready (RR) soybean treated with g...

  12. 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.

  13. Testing Tools for Glyphosate Resistance

    Science.gov (United States)

    There are multiple tools available for testing for glyphosate resistance. Whole plant screens, whether in the field or greenhouse, should be used as an initial method to determine if a biotype is glyphosate resistant. Screening for resistance using seedling assays such as in Petri plates, sand cul...

  14. Glyphosate resistance: state of knowledge.

    Science.gov (United States)

    Sammons, Robert Douglas; Gaines, Todd A

    2014-09-01

    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 enzyme endowing greater resistance to glyphosate. Today, target-gene duplication is a common glyphosate resistance mechanism and could become a fundamental process for developing any resistance trait. Based on competition and substrate selectivity studies in several species, rapid vacuole sequestration of glyphosate occurs via a transporter mechanism. Conversely, as the chloroplast requires transporters for uptake of important metabolites, transporters associated with the two plastid membranes may separately, or together, successfully block glyphosate delivery. A model based on finite glyphosate dose and limiting time required for chloroplast loading sets the stage for understanding how uniquely different mechanisms can contribute to overall glyphosate resistance.

  15. Mode of Action of Glyphosate

    Science.gov (United States)

    Although glyphosate is the most used and studied herbicide in the world, the available information is not enough to fully understand its mode of action. The molecular site of action of glyphosate is the enzyme 5-enolpyruvlyshikimate-3-phosphate synthase (EPSPS). It is the only known compound that ...

  16. 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 μM, and the Ki for orthophosphate was 24 μM. Organophosphonates as well as organophosphates inhibited glyphosate uptake, but only organophosphates and orthophosphate suppressed...

  17. Crop Response to Glyphosate Trimesium Sulphosate

    OpenAIRE

    Danijela PAVLOVIC; VRBNICANIN, Sava; 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...

  18. Path-sensitive analysis for reducing rollback overheads

    Science.gov (United States)

    O'Brien, John K.P.; Wang, Kai-Ting Amy; Yamashita, Mark; Zhuang, Xiaotong

    2014-07-22

    A mechanism is provided for path-sensitive analysis for reducing rollback overheads. The mechanism receives, in a compiler, program code to be compiled to form compiled code. The mechanism divides the code into basic blocks. The mechanism then determines a restore register set for each of the one or more basic blocks to form one or more restore register sets. The mechanism then stores the one or more register sets such that responsive to a rollback during execution of the compiled code. A rollback routine identifies a restore register set from the one or more restore register sets and restores registers identified in the identified restore register set.

  19. 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

  20. 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.

  1. 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.

  2. Investigating the mechanisms of glyphosate resistance in goosegrass (Eleusine indica) population from South China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun; FENG Li; HE Ting-ting; YANG Cai-hong; CHEN Guo-qi; TIAN Xing-shan

    2015-01-01

    Glyphosate has been used worldwide for nearly 40 years, and 30 types of resistant weeds have been reported. Glyphosate is mass-produced and widely used in China, but few studies and reports on glyphosate-resistant weeds and resistance mechanisms exist. Previous studies found a goosegrass species with high glyphosate resistance from orchards in South China and its glyphosate resistant mechanism was described in this study. The cDNA of 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS, EC 2.5.1.19), the target enzyme of glyphosate, was cloned from the glyphosate-resistant and-suscep-tible goosegrass, respectively, and referred as EPSPS-R and EPSPS-S. The Pro106 residue was known to be involved in the glyphosate resistance in most goosegrass populations. However, sequence analysis did not ifnd the mutation at the Pro106 residue in the R biotype EPSPS amino acid sequence. The residue 133 and 382 was mutated in the R biotype EPSPS amino acid sequence instead, but it did not affect the EPSPS-S and EPSPS-R genes sensitivities to glyphosate. RT-PCR and Western blot analyses suggested that EPSPS mRNA and protein are mainly present in the shoot tissues both in the R and S goosegrass biotypes. The EPSPS-R rapidly responds to the glyphosate in R-biotype goosegrass and the induced expression was detected at 12 h post glyphosate treatment. The mRNA and protein expression of EPSPS-R increased constantly as the increasing concentration of glyphosate. However, the expression of the EPSPS-S was not induced signiifcantly by glyphosate in the S goosegrass biotype. Quantiifcation of real-time PCR results showed that the copy number of the EPSPS in R-biotype goosegrass was 4.7 times higher than that in the S goosegrass biotype. Al the results implied that EPSPS gene ampliifcation might mainly caused the glyphosate resistance of a goosegrass population col ected from orchards in South China.

  3. Questions concerning the potential impact of glyphosate-based herbicides on amphibians.

    Science.gov (United States)

    Wagner, Norman; Reichenbecher, Wolfram; Teichmann, Hanka; Tappeser, Beatrix; Lötters, Stefan

    2013-08-01

    Use of glyphosate-based herbicides is increasing worldwide. The authors review the available data related to potential impacts of these herbicides on amphibians and conduct a qualitative meta-analysis. Because little is known about environmental concentrations of glyphosate in amphibian habitats and virtually nothing is known about environmental concentrations of the substances added to the herbicide formulations that mainly contribute to adverse effects, glyphosate levels can only be seen as approximations for contamination with glyphosate-based herbicides. The impact on amphibians depends on the herbicide formulation, with different sensitivity of taxa and life stages. Effects on development of larvae apparently are the most sensitive endpoints to study. As with other contaminants, costressors mainly increase adverse effects. If and how glyphosate-based herbicides and other pesticides contribute to amphibian decline is not answerable yet due to missing data on how natural populations are affected. Amphibian risk assessment can only be conducted case-specifically, with consideration of the particular herbicide formulation. The authors recommend better monitoring of both amphibian populations and contamination of habitats with glyphosate-based herbicides, not just glyphosate, and suggest including amphibians in standardized test batteries to study at least dermal administration.

  4. Water use efficiency by coffee arabica after glyphosate application

    Directory of Open Access Journals (Sweden)

    Felipe Paolinelli de Carvalho

    2014-07-01

    Full Text Available 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 this 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.

  5. Yield of glyphosate-resistant sugar beets and efficiency of weed management systems with glyphosate and conventional herbicides under German and Polish crop production.

    Science.gov (United States)

    Nichterlein, Henrike; Matzk, Anja; Kordas, Leszek; Kraus, Josef; Stibbe, Carsten

    2013-08-01

    In sugar beet production, weed control is one of the most important and most expensive practices to ensure yield. Since glyphosate-resistant sugar beets are not yet approved for cultivation in the EU, little commercial experience exists with these sugar beets in Europe. Experimental field trials were conducted at five environments (Germany, Poland, 2010, 2011) to compare the effects of glyphosate with the effects of conventional weed control programs on the development of weeds, weed control efficiency and yield. The results show that the glyphosate weed control programs compared to the conventional methods decreased not only the number of herbicide applications but equally in magnitude decreased the dosage of active ingredients. The results also showed effective weed control with glyphosate when the weed covering was greater and sugar beets had a later growth stage of four true leaves. Glyphosate-resistant sugar beets applied with the glyphosate herbicide two or three times had an increase in white sugar yield from 4 to 18 % in comparison to the high dosage conventional herbicide systems. In summary, under glyphosate management sugar beets can positively contribute to the increasingly demanding requirements regarding efficient sugar beet cultivation and to the demands by society and politics to reduce the use of chemical plant protection products in the environment.

  6. 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...

  7. Glyphosate effect on plant rhizobacteria

    OpenAIRE

    Giraldo Duque, Judy Madelén

    2015-01-01

    Abstract: Results obtained from several studies suggest that the pre-seeding application of the widely used herbicide glyphosate can alter the microbial community of the rhizosphere of non-target plants, as well as soil processes mediated by microorganisms. Although this impact should be related to the response of weed plants to glyphosate application, little is known on the changes taking place in the microbial community of weed plant rhizosphere. A field and a greenhouse experiments were co...

  8. Non-target Site Tolerance Mechanisms Describe Tolerance to Glyphosate in Avena sterilis.

    Science.gov (United States)

    Fernández-Moreno, Pablo T; Alcantara-de la Cruz, Ricardo; Cruz-Hipólito, Hugo E; Rojano-Delgado, Antonia M; Travlos, Ilias; De Prado, Rafael

    2016-01-01

    Sterile wild oat (Avena sterilis L.) is an autogamous grass established in warm climate regions. This species has been used as a cover crop in Mediterranean perennial crops during the spring period prior to initiating competition with the main crop for water and nutrients. However, such cover crops need to be controlled (by glyphosate or tillage) before the beginning of summer period (due to the possibility of intense drought stress). In 2011, the olive grove farmers of southern Spain expressed dissatisfaction because of the ineffective control with glyphosate on A. sterilis. Experiments were conducted to determine whether the continued use of glyphosate over a 5 year period had selected a new resistant or tolerant species. The GR50 values obtained for A. sterilis were 297.12 and 245.23 g ae ha(-1) for exposed (E) and un-exposed (UE) glyphosate accessions, respectively. The spray retention and shikimic acid accumulation exhibited a non-significant difference between the two accessions. The results of (14)C- glyphosate absorption was the same in the two accessions (E and UE), while the translocation from the treated leaf to the rest of the shoots and roots was similar in A. sterilis accessions. Glyphosate metabolism to aminomethylphosphonic acid (AMPA) and glyoxylate was similar in both accessions, but increased after treatment with glyphosate, indicating that metabolism plays an important role in tolerance. Both A. sterilis accessions, present similarity in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity enzyme with different glyphosate concentrations and without glyphosate, confirming that both accessions present the same genomic characteristics. The above-mentioned results indicate that innate tolerance to glyphosate in A. sterilis is probably and partly due to reduced herbicide absorption and translocation and metabolism compared to the susceptibility of other grasses weeds like Chloris inflata, Eleusine indica, and Lolium rigidum.

  9. Non-target Site Tolerance Mechanisms Describe Tolerance to Glyphosate in Avena sterilis.

    Science.gov (United States)

    Fernández-Moreno, Pablo T; Alcantara-de la Cruz, Ricardo; Cruz-Hipólito, Hugo E; Rojano-Delgado, Antonia M; Travlos, Ilias; De Prado, Rafael

    2016-01-01

    Sterile wild oat (Avena sterilis L.) is an autogamous grass established in warm climate regions. This species has been used as a cover crop in Mediterranean perennial crops during the spring period prior to initiating competition with the main crop for water and nutrients. However, such cover crops need to be controlled (by glyphosate or tillage) before the beginning of summer period (due to the possibility of intense drought stress). In 2011, the olive grove farmers of southern Spain expressed dissatisfaction because of the ineffective control with glyphosate on A. sterilis. Experiments were conducted to determine whether the continued use of glyphosate over a 5 year period had selected a new resistant or tolerant species. The GR50 values obtained for A. sterilis were 297.12 and 245.23 g ae ha(-1) for exposed (E) and un-exposed (UE) glyphosate accessions, respectively. The spray retention and shikimic acid accumulation exhibited a non-significant difference between the two accessions. The results of (14)C- glyphosate absorption was the same in the two accessions (E and UE), while the translocation from the treated leaf to the rest of the shoots and roots was similar in A. sterilis accessions. Glyphosate metabolism to aminomethylphosphonic acid (AMPA) and glyoxylate was similar in both accessions, but increased after treatment with glyphosate, indicating that metabolism plays an important role in tolerance. Both A. sterilis accessions, present similarity in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity enzyme with different glyphosate concentrations and without glyphosate, confirming that both accessions present the same genomic characteristics. The above-mentioned results indicate that innate tolerance to glyphosate in A. sterilis is probably and partly due to reduced herbicide absorption and translocation and metabolism compared to the susceptibility of other grasses weeds like Chloris inflata, Eleusine indica, and Lolium rigidum. PMID:27570531

  10. Non-target Site Tolerance Mechanisms Describe Tolerance to Glyphosate in Avena sterilis

    Science.gov (United States)

    Fernández-Moreno, Pablo T.; Alcantara-de la Cruz, Ricardo; Cruz-Hipólito, Hugo E.; Rojano-Delgado, Antonia M.; Travlos, Ilias; De Prado, Rafael

    2016-01-01

    Sterile wild oat (Avena sterilis L.) is an autogamous grass established in warm climate regions. This species has been used as a cover crop in Mediterranean perennial crops during the spring period prior to initiating competition with the main crop for water and nutrients. However, such cover crops need to be controlled (by glyphosate or tillage) before the beginning of summer period (due to the possibility of intense drought stress). In 2011, the olive grove farmers of southern Spain expressed dissatisfaction because of the ineffective control with glyphosate on A. sterilis. Experiments were conducted to determine whether the continued use of glyphosate over a 5 year period had selected a new resistant or tolerant species. The GR50 values obtained for A. sterilis were 297.12 and 245.23 g ae ha−1 for exposed (E) and un-exposed (UE) glyphosate accessions, respectively. The spray retention and shikimic acid accumulation exhibited a non-significant difference between the two accessions. The results of 14C- glyphosate absorption was the same in the two accessions (E and UE), while the translocation from the treated leaf to the rest of the shoots and roots was similar in A. sterilis accessions. Glyphosate metabolism to aminomethylphosphonic acid (AMPA) and glyoxylate was similar in both accessions, but increased after treatment with glyphosate, indicating that metabolism plays an important role in tolerance. Both A. sterilis accessions, present similarity in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity enzyme with different glyphosate concentrations and without glyphosate, confirming that both accessions present the same genomic characteristics. The above-mentioned results indicate that innate tolerance to glyphosate in A. sterilis is probably and partly due to reduced herbicide absorption and translocation and metabolism compared to the susceptibility of other grasses weeds like Chloris inflata, Eleusine indica, and Lolium rigidum. PMID:27570531

  11. Non-target Site Tolerance Mechanisms Describe Tolerance to Glyphosate in Avena sterilis

    Science.gov (United States)

    Fernández-Moreno, Pablo T.; Alcantara-de la Cruz, Ricardo; Cruz-Hipólito, Hugo E.; Rojano-Delgado, Antonia M.; Travlos, Ilias; De Prado, Rafael

    2016-01-01

    Sterile wild oat (Avena sterilis L.) is an autogamous grass established in warm climate regions. This species has been used as a cover crop in Mediterranean perennial crops during the spring period prior to initiating competition with the main crop for water and nutrients. However, such cover crops need to be controlled (by glyphosate or tillage) before the beginning of summer period (due to the possibility of intense drought stress). In 2011, the olive grove farmers of southern Spain expressed dissatisfaction because of the ineffective control with glyphosate on A. sterilis. Experiments were conducted to determine whether the continued use of glyphosate over a 5 year period had selected a new resistant or tolerant species. The GR50 values obtained for A. sterilis were 297.12 and 245.23 g ae ha−1 for exposed (E) and un-exposed (UE) glyphosate accessions, respectively. The spray retention and shikimic acid accumulation exhibited a non-significant difference between the two accessions. The results of 14C- glyphosate absorption was the same in the two accessions (E and UE), while the translocation from the treated leaf to the rest of the shoots and roots was similar in A. sterilis accessions. Glyphosate metabolism to aminomethylphosphonic acid (AMPA) and glyoxylate was similar in both accessions, but increased after treatment with glyphosate, indicating that metabolism plays an important role in tolerance. Both A. sterilis accessions, present similarity in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity enzyme with different glyphosate concentrations and without glyphosate, confirming that both accessions present the same genomic characteristics. The above-mentioned results indicate that innate tolerance to glyphosate in A. sterilis is probably and partly due to reduced herbicide absorption and translocation and metabolism compared to the susceptibility of other grasses weeds like Chloris inflata, Eleusine indica, and Lolium rigidum.

  12. Foliar temperature acclimation reduces simulated carbon sensitivity to climate

    Science.gov (United States)

    Smith, Nicholas G.; Malyshev, Sergey L.; Shevliakova, Elena; Kattge, Jens; Dukes, Jeffrey S.

    2016-04-01

    Plant photosynthesis and respiration are the largest carbon fluxes between the terrestrial biosphere and the atmosphere, and their parameterizations represent large sources of uncertainty in projections of land carbon uptake in Earth system models (ESMs). The incorporation of temperature acclimation of photosynthesis and foliar respiration, commonly observed processes, into ESMs has been proposed as a way to reduce this uncertainty. Here we show that, across 15 flux tower sites spanning multiple biomes at various locations worldwide (10° S-67° N), acclimation parameterizations improve a model's ability to reproduce observed net ecosystem exchange of CO2. This improvement is most notable in tropical biomes, where photosynthetic acclimation increased model performance by 36%. The consequences of acclimation for simulated terrestrial carbon uptake depend on the process, region and time period evaluated. Globally, including acclimation has a net effect of increasing carbon assimilation and storage, an effect that diminishes with time, but persists well into the future. Our results suggest that land models omitting foliar temperature acclimation are likely to overestimate the temperature sensitivity of terrestrial carbon exchange, thus biasing projections of future carbon storage and estimates of policy indicators such as the transient climate response to cumulative carbon emissions.

  13. Crop Response to Glyphosate Trimesium Sulphosate

    Directory of Open Access Journals (Sweden)

    Danijela PAVLOVIC

    2013-12-01

    Full Text Available 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 sulphosate and to evaluate soybeans injury to help in weed resistance detection. The methods used to detect changes were dose response test, HPLC measurement based on glyphosate induced accumulation of shikimate, and morpho-anatomical changes (light and electron microscopy. Damaged chloroplasts are a clear indication of a glyphosate injury. If the injury rating is related to increased shikimate levels, there is greater certainty that differences among biotypes are due to glyphosate tolerance.

  14. 75 FR 24969 - Glyphosate From China

    Science.gov (United States)

    2010-05-06

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

  15. 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...

  16. 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. ...

  17. 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;

    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...

  18. First case of glyphosate resistance in France

    OpenAIRE

    Fernandez, Pablo; Gauvrit, Christian; Barro, Francisco; Menendez, Julio; De Prado, Rafael

    2015-01-01

    International audience AbstractGlyphosate is a broad-spectrum systemic herbicide used to kill weeds, especially annual broadleaf weeds and grasses known to compete with commercial crops grown around the globe. However, weeds evolve and develop resistance to glyphosate. Until recently, no case of glyphosate resistance had been detected in France. Glyphosate resistance was indeed recently recorded in a Lolium rigidum weed population from a vineyard in the South of France. Here, we studied th...

  19. Effects of glyphosate on brachypodium distachyon

    OpenAIRE

    Altıntaş, Ayşegul; Altintas, Aysegul

    2010-01-01

    Glyphosate is a non-selective herbicide used widely as the most popular weed management tool, especially since the commercialization of glyphosate-resistant crops. Due to overuse, several weed species have evolved resistance towards glyphosate and this trend threatens the future of world food production. Brachypodium distachyon has been proposed as a model organism specifically for economically important crops such as wheat and barley. Thus, evaluating the effects of glyphosate on Brachypodiu...

  20. First case of glyphosate resistance in France

    OpenAIRE

    Fernandez, Pablo; Gauvrit, Christian; Barro, Francisco; Menendez, Julio; De Prado, Rafael

    2015-01-01

    Glyphosate is a broad-spectrum systemic herbicide used to kill weeds, especially annual broadleaf weeds and grasses known to compete with commercial crops grown around the globe. However, weeds evolve and develop resistance to glyphosate. Until recently, no case of glyphosate resistance had been detected in France. Glyphosate resistance was indeed recently recorded in a Lolium rigidum weed population from a vineyard in the South of France. Here, we studied the mechanisms of this resistance ca...

  1. Effects of glyphosate and foliar amendments on activity of microorganisms in the soybean rhizosphere.

    Science.gov (United States)

    Means, Nathan E; Kremer, Robert J; Ramsier, Clifford

    2007-02-01

    A field study was conducted to determine the effects of glyphosate on microbial activity in the rhizosphere of glyphosate-resistant (GR) soybean and to evaluate interactions with foliar amendments. Glyphosate at 0.84 kg ae ha(-1) was applied GR soybean at the V4-V5 development stages. Check treatments included a conventional herbicide tank mix (2003 study only) and no herbicides (hand-weeded). Ten days after herbicide application, a commercially available biostimulant and a urea solution (21.0% N) were applied to soybean foliage at 33.5 mL ha(-1) and 9.2 kg ha(-1), respectively. Soil and plant samples were taken 0, 5, 10, 15, 20 and 25 days after herbicide application then assayed for enzyme and respiration activities. Soil respiration and enzyme activity increased with glyphosate and foliar amendment applications during the 2002 growing season; however, similar increases were not observed in 2003. Contrasting cumulative rainfall between 2002 and 2003 likely accounted for differences in soil microbial activities. Increases in soil microbial activity in 2002 suggest that adequate soil water and glyphosate application acted together to increase microbial activity. Our study suggests that general soil microbial properties including those involving C and N transformations are not sensitive enough to detect effects of glyphosate on rhizosphere microbial activity. Measurements of soil-plant-microbe relationships including specific microbial groups (i.e., root-associated Fusarium spp.) are likely better indicators of impacts of glyphosate on soil microbial ecology.

  2. 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.

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

    OpenAIRE

    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-...

  4. Comparison of Nitrogen Fertilizers, Induce and Zinc Addition on Glyphosate Efficacy on Three Different Weed Species.

    OpenAIRE

    Hussein F. Abouziena; Ibraheem M. El-Metwally; H.M. El-Saeid; Megh Singh

    2014-01-01

    Herbicides are often tank-mixed with fertilizers to save time, labour, energy, and equipment costs. However addition of some additives with glyphosate may result in reducing glyphosate efficacy. Therefore we evaluated the potential of three nitrogen sources (ammonium sulphate (AMS) at 2 or 4% w/v, ammonium nitrate (AN) at 1 or 2% w/v, urea at 1 or 2 % w/v), nonionic adjuvant (Induce at 0.05% v/v) and Zn at 250 g Zn/ha (1321 ppm) to enhance glyphosate efficacy on pig weed (Amaranthus retroflex...

  5. Glyphosate-resistant and conventional canola (Brassica napus L.)responses to glyphosate and Aminomethylphosphonic Acid (AMPA) treatment

    Science.gov (United States)

    Glyphosate-resistant (GR) canola expresses two transgenes: 1) the microbial glyphosate oxidase gene (gox) encoding the glyphosate oxidase enzyme (GOX) that metabolizes glyphosate to aminomethylphosphonic acid (AMPA) and 2) cp4 that encodes a GR form of the glyphosate target enzyme 5-enolpyruvylshiki...

  6. 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

  7. RDX-based nanocomposite microparticles for significantly reduced shock sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Qiu Hongwei, E-mail: hqiu@stevens.edu [Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ 07030 (United States); Stepanov, Victor; Di Stasio, Anthony R. [U.S. Army - Armament Research, Development, and Engineering Center, Picatinny, NJ 07806 (United States); Chou, Tsengming; Lee, Woo Y. [Department of Chemical Engineering and Materials Science, Stevens Institute of Technology, Hoboken, NJ 07030 (United States)

    2011-01-15

    Cyclotrimethylenetrinitramine (RDX)-based nanocomposite microparticles were produced by a simple, yet novel spray drying method. The microparticles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and high performance liquid chromatography (HPLC), which shows that they consist of small RDX crystals ({approx}0.1-1 {mu}m) uniformly and discretely dispersed in a binder. The microparticles were subsequently pressed to produce dense energetic materials which exhibited a markedly lower shock sensitivity. The low sensitivity was attributed to small crystal size as well as small void size ({approx}250 nm). The method developed in this work may be suitable for the preparation of a wide range of insensitive explosive compositions.

  8. 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 μm 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.

  9. Synchronous Sounds Enhance Visual Sensitivity without Reducing Target Uncertainty

    Directory of Open Access Journals (Sweden)

    Yi-Chuan Chen

    2011-10-01

    Full Text Available We examined the crossmodal effect of the presentation of a simultaneous sound on visual detection and discrimination sensitivity using the equivalent noise paradigm (Dosher & Lu, 1998. In each trial, a tilted Gabor patch was presented in either the first or second of two intervals consisting of dynamic 2D white noise with one of seven possible contrast levels. The results revealed that the sensitivity of participants' visual detection and discrimination performance were both enhanced by the presentation of a simultaneous sound, though only close to the noise level at which participants' target contrast thresholds started to increase with the increasing noise contrast. A further analysis of the psychometric function at this noise level revealed that the increase in sensitivity could not be explained by the reduction of participants' uncertainty regarding the onset time of the visual target. We suggest that this crossmodal facilitatory effect may be accounted for by perceptual enhancement elicited by a simultaneously-presented sound, and that the crossmodal facilitation was easier to observe when the visual system encountered a level of noise that happened to be close to the level of internal noise embedded within the system.

  10. 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

  11. 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.

  12. Behavioral responses of juvenile Daphnia magna after exposure to glyphosate and glyphosate-copper complexes.

    Science.gov (United States)

    Hansen, Lone Rykær; Roslev, Peter

    2016-10-01

    Glyphosate (N-(phosphonomethyl)glycine) is the active ingredient in a range of popular broad-spectrum herbicide formulations. Glyphosate is a chelating agent that can form stable complexes with divalent metal ions including Cu(II). Little is known about the bioavailability and ecotoxicity of glyphosate-Cu(II) complexes to aquatic organisms. In this study, we used video tracking and behavior analysis to investigate sublethal effects of binary mixtures of glyphosate and Cu(II) to juvenile D. magna. Behavioral responses were quantified for individual D. magna after 24h and 48h exposure to glyphosate and glyhosate-Cu(II) mixtures. Sublethal concentrations resulted in decreases in swimming velocity, acceleration speed, and distance moved whereas inactive time of D. magna increased. Distance moved and inactive time were the most responsive parameters to glyphosate and glyphosate-Cu(II) exposure. On a molar basis, glyphosate-Cu(II) complexes appeared more toxic to D. magna than glyphosate alone. The 48h EC50 for glyphosate and glyphosate-Cu(II) determined from swimming distance were 75.2μM and 8.4μM, respectively. In comparison, traditional visual observation of mobility resulted in 48h EC50 values of 52.8μM and 25.5μM for glyphosate and glyphosate-Cu(II), respectively. The behavioral responses indicated that exposure of D. magna to mixtures of glyphosate and Cu(II) attenuated acute metal toxicity but increased apparent glyphosate toxicity due to complexation with Cu(II). The study suggests that glyphosate is a likely mediator of aquatic metal toxicity, and that video tracking provides an opportunity for quantitative studies of sublethal effects of pesticide complexes.

  13. 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 ...

  14. Review of potential environmental impacts of transgenic glyphosate-resistant soybean in Brazil.

    Science.gov (United States)

    Cerdeira, Antonio L; Gazziero, Dionsio L P; Duke, Stephen O; Matallo, Marcus B; Spadotto, Claudio A

    2007-01-01

    Transgenic glyphosate-resistant soybeans (GRS) have been commercialized and grown extensively in the Western Hemisphere, including Brazil. Worldwide, several studies have shown that previous and potential effects of glyphosate on contamination of soil, water, and air are minimal, compared to those caused by the herbicides that they replace when GRS are adopted. In the USA and Argentina, the advent of glyphosate-resistant soybeans resulted in a significant shift to reduced- and no-tillage practices, thereby significantly reducing environmental degradation by agriculture. Similar shifts in tillage practiced with GRS might be expected in Brazil. Transgenes encoding glyphosate resistance in soybeans are highly unlikely to be a risk to wild plant species in Brazil. Soybean is almost completely self-pollinated and is a non-native species in Brazil, without wild relatives, making introgression of transgenes from GRS virtually impossible. Probably the highest agricultural risk in adopting GRS in Brazil is related to weed resistance. Weed species in GRS fields have shifted in Brazil to those that can more successfully withstand glyphosate or to those that avoid the time of its application. These include Chamaesyce hirta (erva-de-Santa-Luzia), Commelina benghalensis (trapoeraba), Spermacoce latifolia (erva-quente), Richardia brasiliensis (poaia-branca), and Ipomoea spp. (corda-de-viola). Four weed species, Conyza bonariensis, Conyza Canadensis (buva), Lolium multiflorum (azevem), and Euphorbia heterophylla (amendoim bravo), have evolved resistance to glyphosate in GRS in Brazil and have great potential to become problems. PMID:17562462

  15. 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

    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.

  16. Mildly negative social encounters reduce physical pain sensitivity.

    Science.gov (United States)

    Borsook, Terry K; MacDonald, Geoff

    2010-11-01

    While previous research has demonstrated a reduction in physical pain sensitivity in response to social exclusion, the manipulations employed have arguably been far removed from typical daily experience. The purpose of this study was to investigate the effects of relatively ordinary social encounters on the perception of pain. Healthy participants rated the intensity and unpleasantness of painful stimuli before and after engaging in a structured interaction with a confederate who was instructed to either be warm and friendly or indifferent. A control group was asked to perform a similar structured activity, but alone. Consistent with predictions, participants who experienced the mildly negative social exchange reported lower pain intensity and unpleasantness after the encounter relative to baseline, whereas those exposed to the positive social exchange did not evidence any change in pain ratings. These results were not mediated by changes in mood or perceived connectedness. If mildly negative social encounters can provoke an analgesic effect, it is possible that social hypoalgesia may be considerably more commonplace than previously realized. Discussion focuses on the role of stress-induced hypoalgesia, and the implications of the results for clinical assessments of pain.

  17. Glyphosate-Resistant Goosegrass from Mississippi

    OpenAIRE

    Vijay K. Nandula; Alice A Wright; 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...

  18. The role of L-type amino acid transporters in the uptake of glyphosate across mammalian epithelial tissues.

    Science.gov (United States)

    Xu, Jiaqiang; Li, Gao; Wang, Zhuoyi; Si, Luqin; He, Sijie; Cai, Jialing; Huang, Jiangeng; Donovan, Maureen D

    2016-02-01

    Glyphosate is one of the most commonly used herbicides worldwide due to its broad spectrum of activity and reported low toxicity to humans. Glyphosate has an amino acid-like structure that is highly polar and shows low bioavailability following oral ingestion and low systemic toxicity following intravenous exposures. Spray applications of glyphosate in agricultural or residential settings can result in topical or inhalation exposures to the herbicide. Limited systemic exposure to glyphosate occurs following skin contact, and pulmonary exposure has also been reported to be low. The results of nasal inhalation exposures, however, have not been evaluated. To investigate the mechanisms of glyphosate absorption across epithelial tissues, the permeation of glyphosate across Caco-2 cells, a gastrointestinal epithelium model, was compared with permeation across nasal respiratory and olfactory tissues excised from cows. Saturable glyphosate uptake was seen in all three tissues, indicating the activity of epithelial transporters. The uptake was shown to be ATP and Na(+) independent, and glyphosate permeability could be significantly reduced by the inclusion of competitive amino acids or specific LAT1/LAT2 transporter inhibitors. The pattern of inhibition of glyphosate permeability across Caco-2 and nasal mucosal tissues suggests that LAT1/2 play major roles in the transport of this amino-acid-like herbicide. Enhanced uptake into the epithelial cells at barrier mucosae, including the respiratory and gastrointestinal tracts, may result in more significant local and systemic effects than predicted from glyphosate's passive permeability, and enhanced uptake by the olfactory mucosa may result in further CNS disposition, potentially increasing the risk for brain-related toxicities.

  19. Environmental fate of herbicides trifluralin, metazachlor, metamitron and sulcotrione compared with that of glyphosate, a substitute broad spectrum herbicide for different glyphosate-resistant crops.

    Science.gov (United States)

    Mamy, Laure; Barriuso, Enrique; Gabrielle, Benoît

    2005-09-01

    The introduction of crops resistant to the broad spectrum herbicide glyphosate, N-(phosphonomethyl)glycine, may constitute an answer to increased contamination of the environment by herbicides, since it should reduce the total amount of herbicide needed and the number of active ingredients. However, there are few published data comparing the fate of glyphosate in the environment, particularly in soil, with that of substitute herbicides. The objective of this study is to compare the fate of glyphosate in three soils with that of four herbicides frequently used on crops that might be glyphosate resistant: trifluralin, alpha,alpha,alpha-trifluoro-2,6-dinitro-N,N-dipropyl-p-toluidine, and metazachlor, 2-chloro-N-(pyrazol-1-ylmethyl)acet-2',6'-xylidide for oilseed rape, metamitron, 4-amino-4,5-dihydro-3-methyl-6-phenyl-1,2,4-triazin-5-one for sugarbeet and sulcotrione, 2-(2-chloro-4-mesylbenzoyl)cyclohexane-1,3-dione for maize. The distribution of herbicides between the volatilized, mineralized, extractable and non-extractable fractions was studied, along with the formation of their metabolites in laboratory experiments using 14C-labelled herbicides, over a period of 140 days. The main dissipation pathways were mineralization for glyphosate and sulcotrione, volatilization for trifluralin and non-extractable residues formation for metazachlor and metamitron. The five herbicides had low persistence. Glyphosate had the shortest half-life, which varied with soil type, whereas trifluralin had the longest. The half-lives of metazachlor and sulcotrione were comparable, whereas that of metamitron was highly variable. Glyphosate, metazachlor and sulcotrione were degraded into persistent metabolites. Low amounts of trifluralin and metamitron metabolites were observed. At 140 days after herbicide applications, the amounts of glyphosate and its metabolite residues in soils were the lowest in two soils, but not in the third soil, a loamy sand with low pH. The environmental advantage

  20. Agricultural impacts of glyphosate-resistant soybean cultivation in South America.

    Science.gov (United States)

    Cerdeira, Antonio L; Gazziero, Dionsio L P; Duke, Stephen O; Matallo, Marcus B

    2011-06-01

    In the 2009/2010 growing season, Brazil was the second largest world soybean producer, followed by Argentina. Glyphosate-resistant soybeans (GRS) are being cultivated in most of the soybean area in South America. Overall, the GRS system is beneficial to the environment when compared to conventional soybean. GRS resulted in a significant shift toward no-tillage practices in Brazil and Argentina, but weed resistance may reduce this trend. Probably the highest agricultural risk in adopting GRS in Brazil and South America is related to weed resistance due to use of glyphosate. Weed species in GRS fields have shifted in Brazil to those that can more successfully withstand glyphosate or to those that avoid the time of its application. Five weed species, in order of importance, Conyza bonariensis (L.) Cronquist, Conyza canadensis (L.) Cronquist, Lolium multiflorum Lam., Digitaria insularis (L.) Mez ex Ekman, and Euphorbia heterophylla L., have evolved resistance to glyphosate in GRS in Brazil. Conyza spp. are the most difficult to control. A glyphosate-resistant biotype of Sorghum halepense L. has evolved in GRS in Argentina and one of D. insularis in Paraguay. The following actions are proposed to minimize weed resistance problem: (a) rotation of GRS with conventional soybeans in order to rotate herbicide modes of action; (b) avoidance of lower than recommended glyphosate rates; (c) keeping soil covered with a crop or legume at intercrop intervals; (d) keeping machinery free of weed seeds; and (d) use of a preplant nonselective herbicide plus residuals to eliminate early weed interference with the crop and to minimize escapes from later applications of glyphosate due to natural resistance of older weeds and/or incomplete glyphosate coverage.

  1. Sensitivity of Reliability Estimates in Partially Damaged RC Structures subject to Earthquakes, using Reduced Hysteretic Models

    DEFF Research Database (Denmark)

    Iwankiewicz, R.; Nielsen, Søren R. K.; Skjærbæk, P. S.

    The subject of the paper is the investigation of the sensitivity of structural reliability estimation by a reduced hysteretic model for a reinforced concrete frame under an earthquake excitation.......The subject of the paper is the investigation of the sensitivity of structural reliability estimation by a reduced hysteretic model for a reinforced concrete frame under an earthquake excitation....

  2. 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

  3. Identification of regulated genes conferring resistance to high concentrations of glyphosate in a new strain of Enterobacter.

    Science.gov (United States)

    Fei, Yun-Yan; Gai, Jun-Yi; Zhao, Tuan-Jie

    2013-12-01

    Glyphosate is a widely used herbicide that inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity. Most plants and microbes are sensitive to glyphosate. However, transgenic-resistant crops that contain a modified epsps obtained from the resistant microbes have been commercially successful and therefore, new resistance genes and their adaptive regulatory mechanisms are of great interest. In this study, a soil-borne, glyphosate-resistant bacterium was selected and identified as Enterobacter. The EPSPS in this strain was found to have been altered to a resistant one. A total of 42 differentially expressed genes (DEGs) in the glyphosate were screened using microarray techniques. Under treatment, argF, sdhA, ivbL, rrfA-H were downregulated, whereas the transcripts of speA, osmY, pflB, ahpC, fusA, deoA, uxaC, rpoD and a few ribosomal protein genes were upregulated. Data were verified by quantitative real-time PCR on selected genes. All transcriptional changes appeared to protect the bacteria from glyphosate and associated osmotic, acidic and oxidative stresses. Many DEGs may have the potential to confer resistance to glyphosate alone, and some may be closely related to the shikimate pathway, reflecting the complex gene interaction network for glyphosate resistance.

  4. Linker-assisted immunoassay and liquid chromatography/mass spectrometry for the analysis of glyphosate

    Science.gov (United States)

    Lee, E.A.; Zimmerman, L.R.; Bhullar, B.S.; Thurman, E.M.

    2002-01-01

    A novel, sensitive, linker-assisted enzyme-linked immunosorbent assay (L'ELISA) was compared to on-line solidphase extraction (SPE) with high-performance liquid chromatography/mass spectrometry (HPLC/MS) for the analysis of glyphosate in surface water and groundwater samples. The L'ELISA used succinic anhydride to derivatize glyphosate, which mimics the epitotic attachment of glyphosate to horseradish peroxidase hapten. Thus, L'ELISA recognized the derivatized glyphosate more effectively (detection limit of 0.1 ??g/L) and with increased sensitivity (10-100 times) over conventional ELISA and showed the potential for other applications. The precision and accuracy of L'ELISA then was compared with on-line SPE/HPLC/MS, which detected glyphosate and its degradate derivatized with 9-fluorenylmethyl chloroformate using negative-ion electrospray (detection limit 0.1 ??g/L, relative standard deviation ??15%). Derivatization efficiency and matrix effects were minimized by adding an isotope-labeled glyphosate (2-13C15N). The accuracy of L'ELISA gave a false positive rate of 18% between 0.1 and 1.0 ??g/L and a false positive rate of only 1% above 1.0 ??g/L. The relative standard deviation was ??20%. The correlation of L'ELISA and HPLC/MS for 66 surface water and groundwater samples was 0.97 with a slope of 1.28, with many detections of glyphosate and its degradate in surface water but not in groundwater.

  5. Linker-assisted immunoassay and liquid chromatography/mass spectrometry for the analysis of glyphosate.

    Science.gov (United States)

    Lee, E A; Zimmerman, L R; Bhullar, B S; Thurman, E M

    2002-10-01

    A novel, sensitive, linker-assisted enzyme-linked immunosorbent assay (L'ELISA) was compared to on-line solid-phase extraction (SPE) with high-performance liquid chromatography/mass spectrometry (HPLC/MS) for the analysis of glyphosate in surface water and groundwater samples. The L'ELISA used succinic anhydride to derivatize glyphosate, which mimics the epitotic attachment of glyphosate to horseradish peroxidase hapten. Thus, L'ELISA recognized the derivatized glyphosate more effectively (detection limit of 0.1 microg/L) and with increased sensitivity (10-100 times) over conventional ELISA and showed the potential for other applications. The precision and accuracy of L'ELISA then was compared with on-line SPE/HPLC/MS, which detected glyphosate and its degradate derivatized with 9-fluorenylmethyl chloroformate using negative-ion electrospray (detection limit 0.1 microg/ L, relative standard deviation +/- 15%). Derivatization efficiency and matrix effects were minimized by adding an isotope-labeled glyphosate (2-13C15N). The accuracy of L'EUSA gave a false positive rate of 18% between 0.1 and 1.0 microg/L and a false positive rate of only 1% above 1.0 microg/L The relative standard deviation was +/- 20%. The correlation of L'ELISA and HPLC/MS for 66 surface water and groundwater samples was 0.97 with a slope of 1.28, with many detections of glyphosate and its degradate in surface water but not in groundwater.

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

    Directory of Open Access Journals (Sweden)

    L. Vargas

    2007-09-01

    com mecanismo de ação distinto daquele do glyphosate. Entretanto, o biótipo resistente mostra baixa resposta ao herbicida glyphosate, mesmo se este for empregado em doses elevadas, evidenciando ter adquirido resistência a esse produto.Glyphosate is a non-selective herbicide used for over 20 years to control weeds in Rio Grande do Sul. Horseweed (Conyza bonariensis is a common weed in Rio Grande do Sul and traditionally sensitive to glyphosate. However, during the last years, some horseweed plants have not shown significant injury symptoms after treatment with glyphosate, suggesting that they are resistant to this herbicide. Aiming to evaluate the response of a population of horseweed plants to glyphosate, one field and two greenhouse experiments were carried out. The field experiment treatment had increasing rates of glyphosate (0, 360, 720, 1,440, 2,880 and 5,760 g ha-1, and also the herbicides paraquat and 2,4-D as standards. The greenhouse experiments had increasing rates of glyphosate (0, 360, 720, 1,440, 2,880 and 5,760 g 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, the treatments were increasing rates of glyphosate (720, 1,440 and 2,880 g ha-1 and herbicides chlorimuron-ethyl, metsulfuron-methyl, 2,4-D, paraquat and diuron + paraquat sprayed on plants of resistant and susceptible biotypes. Horseweed control was accessed at 7, 15 and 30 DAT (days after treatment. Overall results of the field and greenhouse experiments provided evidence that the susceptible biotype is easily controlled by glyphosate and the other tested herbicides. In addition, the results demonstrated that the resistant biotype, as the susceptible biotype, is highly sensitive to herbicides with mode of action that differs from glyphosate. However, the resistant biotype showed low response to glyphosate, even at very high rates, confirming resistance of this horseweed

  7. 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.

  8. Adjuvants for single droplet application of glyphosate

    DEFF Research Database (Denmark)

    Mathiassen, Solvejg Kopp; Kudsk, Per; Lund, Ivar

    2016-01-01

    Retention and biological activity of droplets of glyphosate deposited onto plant leaves using a Drop on Demand inkjet printer application system, was examined on pot-grown Brassica napus, Solanum nigrum, Chenopodium album, Silene noctiflora and Echinocloa crus-galli plants. Retention was measured...... but the biological activity of glyphosate was not improved....

  9. 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...

  10. Adjuvants for single droplet application of glyphosate

    DEFF Research Database (Denmark)

    Mathiassen, Solvejg K.; Kudsk, Per; Lund, Ivar

    Retention and biological activity of droplets of glyphosate deposited onto plant leaves using a Drop on Demand inkjet printer application system, was examined on pot-grown Brassica napus, Solanum nigrum, Chenopodium album, Silene noctiflora and Echinocloa crus-galli plants. Retention was measured...... but the biological activity of glyphosate was not improved....

  11. Expression of an evolved engineered variant of a bacterial glycine oxidase leads to glyphosate resistance in alfalfa.

    Science.gov (United States)

    Nicolia, A; Ferradini, N; Molla, G; Biagetti, E; Pollegioni, L; Veronesi, F; Rosellini, D

    2014-08-20

    The main strategy for resistance to the herbicide glyphosate in plants is the overexpression of an herbicide insensitive, bacterial 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). A glyphosate resistance strategy based on the ability to degrade the herbicide can be useful to reduce glyphosate phytotoxicity to the crops. Here we present the characterization of glyphosate resistance in transgenic alfalfa (Medicago sativa L.) expressing a plant-optimized variant of glycine oxidase (GO) from Bacillus subtilis, evolved in vitro by a protein engineering approach to efficiently degrade glyphosate. Two constructs were used, one with (GO(TP+)) and one without (GO(TP-)) the pea rbcS plastid transit peptide. Molecular and biochemical analyses confirmed the stable integration of the transgene and the correct localization of the plastid-imported GO protein. Transgenic alfalfa plants were tested for glyphosate resistance both in vitro and in vivo. Two GO(TP+) lines showed moderate resistance to the herbicide in both conditions. Optimization of expression of this GO variant may allow to attain sufficient field resistance to glyphosate herbicides, thus providing a resistance strategy based on herbicide degradation.

  12. 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

  13. Nodulation and mycorrhization of transgenic soybean after glyphosate application

    Directory of Open Access Journals (Sweden)

    Aloisio Freitas Chagas Junior

    2013-12-01

    Full Text Available The sensitivity of nitrogen-fixing bacteria like Bradyrhizobium spp with in relation to glyphosate can be influenced by the concentration of the herbicide. This study aims to evaluate the effects of two formulations of glyphosate, in two application periods, on nodulation and mycorrhization in a soybean of variety RR P98Y11, using greenhouse, in pots with capacity of 4 L with savanna soils. Six treatments were utilized using Roundup Ultra and Roundup Original with one and two applications, witness without herbicide and witness only with mineral nitrogen, in a completely randomized design. Four evaluations were done, every 15 days, to determine the plant height, shoot and root dry weight, number of nodules, nodule dry weigh and mycorrhizae. It was observed an increase on the number of nodules, with the use of Roundup Ultra until 15 days after the first application. After this period, the witness only with inoculants showed a larger number of nodules. Roundup Ultra had positive influences on the dry weight of nodules, regardless the number of applications. There was no influence of glyphosate formulation considering the mycorrhizal colonization.

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

    Science.gov (United States)

    Sharkhuu, Altanbadralt; Narasimhan, Meena L; Merzaban, Jasmeen S; Bressan, Ray A; Weller, Steve; Gehring, Chris

    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.

  17. 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.

  18. Sensitivity-enhanced and noise-reduced surface plasmon resonance sensing with microwell chips

    International Nuclear Information System (INIS)

    In this paper, we study a surface plasmon resonance (SPR) sensor with a microwell chip that is aimed at improving the sensitivity and reducing the noise. We present both theoretical simulations and experimental results obtained for the proposed structure. In comparison to most SPR sensors that use planar gold films, this proposed well structure enables a sensitivity enhancement of 128%. By confining the surface plasmon wave (SPW) within the well, we are able to reduce the noise by more than twice. The increased sensitivity and lower noise makes our proposed novel microwell chip suitable for small molecule or trace amount detection. (paper)

  19. 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

  20. 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.

  1. 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.

  2. Use of chlorophyll lfuorescence and P700 absorbance to rapidly detect glyphosate resistance in goosegrass (Eleusine indica)

    Institute of Scientific and Technical Information of China (English)

    ZHANG Tai-jie; FENG Li; TIAN Xing-shan; YANG Cai-hong; GAO Jia-dong

    2015-01-01

    The rapid detection of glyphosate resistance in goosegrass (Eleusine indica) wil enhance our ability to respond to new resistant populations of this major weed. Chlorophyl lfuorescence (Fluo) and P700 (reaction center chlorophyl of pho-tosystem I) absorbance were analyzed in one biotype of goosegrass that is resistant to glyphosate and in another that remains sensitive to the herbicide. Both biotypes were treated with a foliar spray of glyphosate. Differences in photosys-tem II maximum quantum yield (Fv/Fm), effective photochemical quantum yield (Y(II)), and non-photochemical quenching (NPQ) between the biotypes increased over time. Values for Fv/Fm and Y(II) differed between the two biotypes 24 h after treatment (HAT). Differentiated activities and energy dissipation processes of photosystem II (PSII) and energy dissipation processes of photosystem I (PSI) were manifested in the two biotypes 24 HAT with 20 mmol L–1 glyphosate. Differentiated energy dissipation processes of PSI were stil apparent 24 HAT with 200 mmol L–1 glyphosate. These results indicate that the Fluo parameters related to PSII activity and energy dissipation and the P700 parameters related to energy dissipation are suitable indicators that enable rapid detection of glyphosate resistance in goosegrass.

  3. 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

  4. A 3D scaffold for ultra-sensitive reduced graphene oxide gas sensors

    Science.gov (United States)

    Yun, Yong Ju; Hong, Won G.; Choi, Nak-Jin; Park, Hyung Ju; Moon, Seung Eon; Kim, Byung Hoon; Song, Ki-Bong; Jun, Yongseok; Lee, Hyung-Kun

    2014-05-01

    An ultra-sensitive gas sensor based on a reduced graphene oxide nanofiber mat was successfully fabricated using a combination of an electrospinning method and graphene oxide wrapping through an electrostatic self-assembly, followed by a low-temperature chemical reduction. The sensor showed excellent sensitivity to NO2 gas.An ultra-sensitive gas sensor based on a reduced graphene oxide nanofiber mat was successfully fabricated using a combination of an electrospinning method and graphene oxide wrapping through an electrostatic self-assembly, followed by a low-temperature chemical reduction. The sensor showed excellent sensitivity to NO2 gas. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr00332b

  5. Concerns over use of glyphosate-based herbicides and risks associated with exposures: a consensus statement.

    Science.gov (United States)

    Myers, John Peterson; Antoniou, Michael N; Blumberg, Bruce; Carroll, Lynn; Colborn, Theo; Everett, Lorne G; Hansen, Michael; Landrigan, Philip J; Lanphear, Bruce P; Mesnage, Robin; Vandenberg, Laura N; Vom Saal, Frederick S; Welshons, Wade V; Benbrook, Charles M

    2016-02-17

    The broad-spectrum herbicide glyphosate (common trade name "Roundup") was first sold to farmers in 1974. Since the late 1970s, the volume of glyphosate-based herbicides (GBHs) applied has increased approximately 100-fold. Further increases in the volume applied are likely due to more and higher rates of application in response to the widespread emergence of glyphosate-resistant weeds and new, pre-harvest, dessicant use patterns. GBHs were developed to replace or reduce reliance on herbicides causing well-documented problems associated with drift and crop damage, slipping efficacy, and human health risks. Initial industry toxicity testing suggested that GBHs posed relatively low risks to non-target species, including mammals, leading regulatory authorities worldwide to set high acceptable exposure limits. To accommodate changes in GBH use patterns associated with genetically engineered, herbicide-tolerant crops, regulators have dramatically increased tolerance levels in maize, oilseed (soybeans and canola), and alfalfa crops and related livestock feeds. Animal and epidemiology studies published in the last decade, however, point to the need for a fresh look at glyphosate toxicity. Furthermore, the World Health Organization's International Agency for Research on Cancer recently concluded that glyphosate is "probably carcinogenic to humans." In response to changing GBH use patterns and advances in scientific understanding of their potential hazards, we have produced a Statement of Concern drawing on emerging science relevant to the safety of GBHs. Our Statement of Concern considers current published literature describing GBH uses, mechanisms of action, toxicity in laboratory animals, and epidemiological studies. It also examines the derivation of current human safety standards. We conclude that: (1) GBHs are the most heavily applied herbicide in the world and usage continues to rise; (2) Worldwide, GBHs often contaminate drinking water sources, precipitation, and air

  6. 75 FR 20862 - Glyphosate From China

    Science.gov (United States)

    2010-04-21

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

  7. 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 1 mg l(-1)) and PO4(3-) (0, 200 and 400 mg l(-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.

  8. 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 1 mg l(-1)) and PO4(3-) (0, 200 and 400 mg l(-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

  9. Reduced graphene oxide electrically contacted graphene sensor for highly sensitive nitric oxide detection.

    Science.gov (United States)

    Li, Weiwei; Geng, Xiumei; Guo, Yufen; Rong, Jizan; Gong, Youpin; Wu, Liqiong; Zhang, Xuemin; Li, Peng; Xu, Jianbao; Cheng, Guosheng; Sun, Mengtao; Liu, Liwei

    2011-09-27

    We develop graphene-based devices fabricated by alternating current dielectrophoresis (ac-DEP) for highly sensitive nitric oxide (NO) gas detection. The novel device comprises the sensitive channels of palladium-decorated reduced graphene oxide (Pd-RGO) and the electrodes covered with chemical vapor deposition (CVD)-grown graphene. The highly sensitive, recoverable, and reliable detection of NO gas ranging from 2 to 420 ppb with response time of several hundred seconds has been achieved at room temperature. The facile and scalable route for high performance suggests a promising application of graphene devices toward the human exhaled NO and environmental pollutant detections. PMID:21834585

  10. Effect of Glyphosate on Symbiotic N2 Fixation and Nickel Concentration in Glyphosate-Resistant Soybean

    Science.gov (United States)

    The impact of widespread cultivation of glyphosate-resistant (GR) soybean and the use of one herbicide class on biological processes has received considerable attention. Decreased biological nitrogen fixation in GR soybean has been attributed directly to toxicity of glyphosate or its metabolites to ...

  11. Interactive effects of temperature and glyphosate on the behavior of blue ridge two-lined salamanders (Eurycea wilderae).

    Science.gov (United States)

    Gandhi, Jaina S; Cecala, Kristen K

    2016-09-01

    The objective of the present study was to evaluate the potential interactive effects of stream temperatures and environmentally relevant glyphosate-based herbicide concentrations on movement and antipredator behaviors of larval Eurycea wilderae (Blue Ridge two-lined salamander). Larval salamanders were exposed to 1 of 4 environmentally relevant glyphosate concentrations (0.00 µg acid equivalent [a.e.]/L, 0.73 µg a.e./L, 1.46 µg a.e./L, and 2.92 µg a.e./L) at either ambient (12 °C) or elevated (23 °C) water temperature. Behaviors observed included the exploration of a novel habitat, use of refuge, habitat selection relative to a potential predator, and burst movement distance. In the absence of glyphosate, temperature consistently affected movement and refuge-use behavior, with individuals moving longer distances more frequently and using refuge less at warm temperatures; however, when glyphosate was added, the authors observed inconsistent effects of temperature that may have resulted from differential toxicity at various temperatures. Larval salamanders made shorter, more frequent movements and demonstrated reduced burst distance at higher glyphosate concentrations. The authors also found that lower glyphosate concentrations sometimes had stronger effects than higher concentrations (i.e., nonmonotonic dose responses), suggesting that standard safety tests conducted only at higher glyphosate concentrations might overlook important sublethal effects on salamander behavior. These data demonstrate that sublethal effects of glyphosate-based herbicides on natural behaviors of amphibians can occur with short-term exposure to environmentally relevant concentrations. Environ Toxicol Chem 2016;35:2297-2303. © 2016 SETAC.

  12. 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 ...

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

    OpenAIRE

    Irina Chamine; 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...

  14. Glyphosate no controle de biótipos de azevém e impacto na microbiota do solo Glyphosate application for italian ryegrass biotype control and impact on soil microbiota

    Directory of Open Access Journals (Sweden)

    E.A. Ferreira

    2006-09-01

    Full Text Available Avaliou-se neste trabalho a resistência de azevém (L. multiflorum ao glyphosate e o impacto do controle desses biótipos sobre a respiração e biomassa microbiana do solo. Foram conduzidos dois ensaios: no primeiro foram avaliadas a intoxicação e a massa seca das plantas de biótipos de três populações de azevém: população 1 (reconhecidamente resistente, população 2 (resistência intermediária, e população 3 (sensível ao glyphosate, submetidas a diferentes doses de glyphosate (200, 400, 800, 1.600 e 3.200 g ha-1. No segundo ensaio foram avaliados a massa seca da parte aérea, a altura de plantas, o número de folhas de azevém e a respiração e massa microbiana do solo cultivado com os biótipos resistente e sensível, com e sem aplicação de glyphosate (480 g ha-1. Aos 14 DAT, observou-se morte do biótipo sensível quando tratado com doses a partir de 200 g ha-1 de glyphosate. Nos biótipos resistentes e com nível intermediário de resistência, a toxicidade do glyphosate às plantas de azevém foi de 85% na maior dose avaliada. O biótipo resistente apresentou maior produção de massa seca da parte aérea aos 42 DAT e na rebrota, aos 72 DAT, quando comparado ao biótipo intermediário. O biótipo sensível apresentou maior altura de plantas, número de folhas e massa seca da parte aérea, em comparação ao resistente, quando não tratados com o glyphosate. Não foi observada diferença na atividade microbiana do solo entre os tratamentos avaliados.This study aimed to evaluate the resistance Italian ryegrass (L. multiflorum against glyphosate and the impact of the control of these biotypes on soil respiration and microbial biomass. Two essays were conducted: the first evaluated intoxication and dry mass of the plants of biotypes of three Italian ryegrass population (population 1 - resistant; population 2 - intermediary resistance; and population 3 - sensitive to glyphosate submitted to different glyphosate rates. The

  15. Manganese uptake and redistribution in soybean as affected by glyphosate

    OpenAIRE

    Ciro Antonio Rosolem; Gabriel José Massoni de Andrade; Izaias Pinheiro Lisboa; Samuel Menegatti Zoca

    2010-01-01

    Detrimental effects of glyphosate on plant mineral nutrition have been reported in the literature, particularly on Mn uptake and redistribution. However, in most of the experiments conducted so far glyphosate-susceptible plants were used. Effects of glyphosate on Mn absorption kinetics, accumulation, and distribution within the plant, as well as soybean response to Mn as affected by glyphosate were studied in three experiments. In the first experiment, in nutrient solution, the effect of glyp...

  16. Glyphosate and its formulations – Toxicity, occupational and environmental exposure

    OpenAIRE

    Marta Kwiatkowska; Paweł Jarosiewicz; Bożena Bukowska

    2013-01-01

    Glyphosate (N-(phosphonomethyl)glycine) is an active ingredient of the most widely used herbicide formulations in protecting agricultural and horticultural crops. Numerous results (mostly published in the years 2010-2013) concerning the action of glyphosate and its formulations in the recent decade were analyzed. Initial reports about alleged biodegradability of glyphosate in the environment turned out to be wrong. It has been shown that glyphosate remains in the soil and can reach people by ...

  17. Economic assessment of alternatives for glyphosate application in arable farming

    OpenAIRE

    Kehlenbeck, Hella; Saltzmann, Jovanka; Schwarz, Jürgen; Zwerger, Peter; Nordmeyer, Henning

    2016-01-01

    Application and sales of herbicides with glyphosate have strongly increased in Germany during the past 10 years. This has raised a number of questions and discussions concerning glyphosate use. Therefore, this paper identifies and evaluates alternatives with an efficacy almost equivalent to glyphosate for different treatmentareas in terms of economic consequences for farms in comparison to glyphosate use by way of example. With the help of exemplary crop rotations uses in arable farming fo...

  18. 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...

  19. 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…

  20. Glyphosate and its formulations – Toxicity, occupational and environmental exposure

    Directory of Open Access Journals (Sweden)

    Marta Kwiatkowska

    2013-10-01

    Full Text Available Glyphosate (N-(phosphonomethylglycine is an active ingredient of the most widely used herbicide formulations in protecting agricultural and horticultural crops. Numerous results (mostly published in the years 2010-2013 concerning the action of glyphosate and its formulations in the recent decade were analyzed. Initial reports about alleged biodegradability of glyphosate in the environment turned out to be wrong. It has been shown that glyphosate remains in the soil and can reach people by spreading along with groundwater. Recent publications have shown that glyphosate is detected at low concentrations in the human blood. Publications cited in this article, which indicate a possible induction of neoplastic changes by glyphosate formulation, have raised great concern and controversy in the scientific world. Presenting adverse effects of glyphosate and its formulations we focused on the role of glyphosate formulations in hormonal disorders by impeding the expression of steroidogenic acute regulatory protein and the inhibition of aromatase activity. The impact of glyphosate on oxygen reactive species formation, changes in redox system and the effect on necrosis and apoptosis in various types of cells was shown. We also revealed that glyphosate as a phosphonate herbicide does not inhibit directly the activity of acetylcholinesterase. Based on numerous studies it was noted that commercial formulations of glyphosate exhibit higher toxicity than that of the active substance itself. The discussed problems clearly show the need to evaluate the toxicity of glyphosate and its formulations and related potential threat to humans. Med Pr 2013;64(5:717–729

  1. 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.; Vargas, L.

    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...

  2. Glyphosate-Resistant and Conventional Canola (Brassica napus L.) Responses to Glyphosate and Aminomethylphosphonic Acid (AMPA) Treatment.

    Science.gov (United States)

    Corrêa, Elza Alves; Dayan, Franck E; Owens, Daniel K; Rimando, Agnes M; Duke, Stephen O

    2016-05-11

    Glyphosate-resistant (GR) canola contains two transgenes that impart resistance to the herbicide glyphosate: (1) the microbial glyphosate oxidase gene (gox) encoding the glyphosate oxidase enzyme (GOX) that metabolizes glyphosate to aminomethylphosphonic acid (AMPA) and (2) cp4 that encodes a GR form of the glyphosate target enzyme 5-enolpyruvylshikimic acid-3-phosphate synthase. The objectives of this research were to determine the phytotoxicity of AMPA to canola, the relative metabolism of glyphosate to AMPA in GR and conventional non-GR (NGR) canola, and AMPA pool sizes in glyphosate-treated GR canola. AMPA applied at 1.0 kg ha(-1) was not phytotoxic to GR or NGR. At this AMPA application rate, NGR canola accumulated a higher concentration of AMPA in its tissues than GR canola. At rates of 1 and 3.33 kg ae ha(-1) of glyphosate, GR canola growth was stimulated. This stimulatory effect is similar to that of much lower doses of glyphosate on NGR canola. Both shikimate and AMPA accumulated in tissues of these glyphosate-treated plants. In a separate experiment in which young GR and NGR canola plants were treated with non-phytotoxic levels of [(14)C]-glyphosate, very little glyphosate was metabolized in NGR plants, whereas most of the glyphosate was metabolized to AMPA in GR plants at 7 days after application. Untreated leaves of GR plants accumulated only metabolites (mostly AMPA) of glyphosate, indicating that GOX activity is very high in the youngest leaves. These data indicate that more glyphosate is transformed to AMPA rapidly in GR canola and that the accumulated AMPA is not toxic to the canola plant. PMID:27092715

  3. Glyphosate-Resistant and Conventional Canola (Brassica napus L.) Responses to Glyphosate and Aminomethylphosphonic Acid (AMPA) Treatment.

    Science.gov (United States)

    Corrêa, Elza Alves; Dayan, Franck E; Owens, Daniel K; Rimando, Agnes M; Duke, Stephen O

    2016-05-11

    Glyphosate-resistant (GR) canola contains two transgenes that impart resistance to the herbicide glyphosate: (1) the microbial glyphosate oxidase gene (gox) encoding the glyphosate oxidase enzyme (GOX) that metabolizes glyphosate to aminomethylphosphonic acid (AMPA) and (2) cp4 that encodes a GR form of the glyphosate target enzyme 5-enolpyruvylshikimic acid-3-phosphate synthase. The objectives of this research were to determine the phytotoxicity of AMPA to canola, the relative metabolism of glyphosate to AMPA in GR and conventional non-GR (NGR) canola, and AMPA pool sizes in glyphosate-treated GR canola. AMPA applied at 1.0 kg ha(-1) was not phytotoxic to GR or NGR. At this AMPA application rate, NGR canola accumulated a higher concentration of AMPA in its tissues than GR canola. At rates of 1 and 3.33 kg ae ha(-1) of glyphosate, GR canola growth was stimulated. This stimulatory effect is similar to that of much lower doses of glyphosate on NGR canola. Both shikimate and AMPA accumulated in tissues of these glyphosate-treated plants. In a separate experiment in which young GR and NGR canola plants were treated with non-phytotoxic levels of [(14)C]-glyphosate, very little glyphosate was metabolized in NGR plants, whereas most of the glyphosate was metabolized to AMPA in GR plants at 7 days after application. Untreated leaves of GR plants accumulated only metabolites (mostly AMPA) of glyphosate, indicating that GOX activity is very high in the youngest leaves. These data indicate that more glyphosate is transformed to AMPA rapidly in GR canola and that the accumulated AMPA is not toxic to the canola plant.

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

    Directory of Open Access Journals (Sweden)

    Bingfu eGuo

    2015-10-01

    Full Text Available 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 four-fold 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.

  5. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis

    Directory of Open Access Journals (Sweden)

    Eleni Tani

    2016-04-01

    Full Text Available Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11 on glyphosate susceptible (GS and glyphosate resistant (GR horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha−1 and high rates (4×, 8×, measured at an early one day after treatment (DAT and a later stage (four DAT of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C. GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation and molecularly (expression of EPSPS and ABC-genes like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance.

  6. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis.

    Science.gov (United States)

    Tani, Eleni; Chachalis, Demosthenis; Travlos, Ilias S; Bilalis, Dimitrios

    2016-04-20

    Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light) on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11) on glyphosate susceptible (GS) and glyphosate resistant (GR) horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha(-1)) and high rates (4×, 8×), measured at an early one day after treatment (DAT) and a later stage (four DAT) of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C). GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation) and molecularly (expression of EPSPS and ABC-genes) like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance.

  7. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis

    Science.gov (United States)

    Tani, Eleni; Chachalis, Demosthenis; Travlos, Ilias S.; Bilalis, Dimitrios

    2016-01-01

    Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light) on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11) on glyphosate susceptible (GS) and glyphosate resistant (GR) horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha−1) and high rates (4×, 8×), measured at an early one day after treatment (DAT) and a later stage (four DAT) of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C). GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation) and molecularly (expression of EPSPS and ABC-genes) like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance. PMID:27104532

  8. Environmental Conditions Influence Induction of Key ABC-Transporter Genes Affecting Glyphosate Resistance Mechanism in Conyza canadensis.

    Science.gov (United States)

    Tani, Eleni; Chachalis, Demosthenis; Travlos, Ilias S; Bilalis, Dimitrios

    2016-01-01

    Conyza canadensis has been reported to be the most frequent weed species that evolved resistance to glyphosate in various parts of the world. The objective of the present study was to investigate the effect of environmental conditions (temperature and light) on the expression levels of the EPSPS gene and two major ABC-transporter genes (M10 and M11) on glyphosate susceptible (GS) and glyphosate resistant (GR) horseweed populations, collected from several regions across Greece. Real-time PCR was conducted to determine the expression level of the aforementioned genes when glyphosate was applied at normal (1×; 533 g·a.e.·ha(-1)) and high rates (4×, 8×), measured at an early one day after treatment (DAT) and a later stage (four DAT) of expression. Plants were exposed to light or dark conditions, at three temperature regimes (8, 25, 35 °C). GR plants were made sensitive when exposed to 8 °C with light; those sensitized plants behaved biochemically (shikimate accumulation) and molecularly (expression of EPSPS and ABC-genes) like the GS plants. Results from the current study show the direct link between the environmental conditions and the induction level of the above key genes that likely affect the efficiency of the proposed mechanism of glyphosate resistance. PMID:27104532

  9. An optical fiber spool for laser stabilization with reduced acceleration sensitivity to 10-12/g

    Institute of Scientific and Technical Information of China (English)

    胡永奇; 董靖; 黄军超; 李唐; 刘亮

    2015-01-01

    Environmental vibration causes mechanical deformation in optical fibers, which induces excess frequency noise in fiber-stabilized lasers. In order to solve such a problem, we propose an ultralow acceleration sensitivity fiber spool with symmetrically mounted structure. By numerical analysis with the finite element method, we obtain the optimal geometry parameters of the spool with which the horizontal and vertical acceleration sensitivity can be reduced to 3.25 × 10−12/g and 5.38 × 10−12/g respectively. Moreover, the structure features the insensitivity to the variation of geometry parameters, which will minimize the infl uence from numerical simulation error and manufacture tolerance.

  10. 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

    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

  11. Glyphosate induces cardiovascular toxicity in Danio rerio.

    Science.gov (United States)

    Roy, Nicole M; Ochs, Jeremy; Zambrzycka, Ewelina; Anderson, Ariann

    2016-09-01

    Glyphosate is a broad spectrum herbicide used aggressively in agricultural practices as well as home garden care. Although labeled "safe" by the chemical industry, doses tested by industry do not mimic chronic exposures to sublethal doses that organisms in the environment are exposed to over long periods of time. Given the widespread uses of and exposure to glyphosate, studies on developmental toxicity are needed. Here we utilize the zebrafish vertebrate model system to study early effects of glyphosate on the developing heart. Treatment by embryo soaking with 50μg/ml glyphosate starting at gastrulation results in structural abnormalities in the atrium and ventricle, irregular heart looping, situs inversus as well as decreased heartbeats by 48h as determined by live imaging and immunohistochemistry. Vasculature in the body was also affected as determined using fli-1 transgenic embryos. To determine if the effects noted at 48h post fertilization are due to early stage alterations in myocardial precursors, we also investigate cardiomyocyte development with a Mef2 antibody and by mef2ca in situ hybridization and find alterations in the Mef2/mef2ca staining patterns during early cardiac patterning stages. We conclude that glyphosate is developmentally toxic to the zebrafish heart.

  12. 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%.

  13. First report of reduced sensitivity towards hydrogen peroxide found in the salmon louse Lepeophtheirus salmonis in Norway

    Directory of Open Access Journals (Sweden)

    Kari Olli Helgesen

    2015-05-01

    Full Text Available Reduced sensitivity towards chemotherapeutants in the salmon louse Lepeophtheirus salmonis (Krøyer is an increasing problem for the fish farming industry. Most fish farmers are dependent on chemical treatments in order to maintain salmon lice numbers below permitted levels. However parasites showing reduced sensitivity contribute to complicating this task. Hydrogen peroxide (H2O2 is used as a delousing agent in bath treatments and until recently treatment failures due to reduced H2O2-sensitivity have not been documented in Norway. The aim of the current study was to develop a bioassay protocol suitable for testing H2O2-sensitivity in L. salmonis. If failed treatments were found to be caused by parasite insensitivity to H2O2 the possibility of this reduced sensitivity being hereditary was looked into. The results show that bioassays permit differentiation between strains of salmon lice with regards to H2O2-sensitivity, coinciding with treatment efficacies. Up to ten times variance in sensitivity between two strains was recorded. The progeny of the least sensitive salmon lice also showed reduced sensitivity to H2O2 in a bioassay, which indicates that reduced sensitivity towards H2O2 is hereditary. The current study presents the first case report of reduced sensitivity towards H2O2 in salmon lice in Norway. This change in sensitivity imposes a threat to the Norwegian fish farming industry and should be monitored closely.

  14. DESIGNING REDUCED-ORDER CONTROLLERS OF MIXED SENSITIVITY PROBLEM FOR FLIGHT CONTROL SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Based on linear matrix inequalities (LMI), the design method of reduced-order controllers of mixed sensitivity problem is studied for flight control systems. It is shown that there exists a controller with order not greater than the difference between the generalized plant order and the number of independent control variables, if the mixed sensitivity problem is solvable for strict regular flight control plants. The proof is constructive, and an approach to design such a controller can be obtained in terms of a pair of feasible solution to the well-known 3 LMI. Finally, an example of mixed sensitivity problem for a flight control system is given to demonstrate practice of the approach.

  15. Reduced graphene oxide-yttria nanocomposite modified electrode for enhancing the sensitivity of electrochemical genosensor.

    Science.gov (United States)

    Rasheed, P Abdul; Radhakrishnan, Thulasi; Shihabudeen, P K; Sandhyarani, N

    2016-09-15

    Reduced graphene oxide-yttria nanocomposite (rGO:Y) is applied as electrochemical genosensor platform for ultrahigh sensitive detection of breast cancer 1 (BRCA1) gene for the first time. The sensor is based on the sandwich assay in which gold nanoparticle cluster labeled reporter DNA hybridize to the target DNA. Glassy carbon electrode modified with rGO-yttria serves as the immobilization platform for capture probe DNA. The sensor exhibited a fine capability of sensing BRCA1 gene with linear range of 10attomolar (aM) to 1nanomolar (nM) and a detection limit of 5.95attomolar. The minimum distinguishable response concentration is down to the attomolar level with a high sensitivity and selectivity. We demonstrated that the use of rGO:Y modified electrode along with gold nanoparticle cluster (AuNPC) label leads to the highly sensitive electrochemical detection of BRCA1 gene. PMID:27153526

  16. Possible glyphosate tolerance mechanism in pitted morningglory (Ipomoea lacunosa L.).

    Science.gov (United States)

    Ribeiro, Daniela N; Nandula, Vijay K; Dayan, Franck E; Rimando, Agnes M; Duke, Stephen O; Reddy, Krishna N; Shaw, David R

    2015-02-18

    Natural tolerance of Ipomoea lacunosa to glyphosate has made it problematic in the southeastern U.S. since the adoption of glyphosate-resistant crops. Experiments were conducted to determine (i) the variability in tolerance to glyphosate among accessions, (ii) if there is any correlation between metabolism of glyphosate to aminomethylphosponic acid (AMPA) or sarcosine and the level of tolerance, and (iii) the involvement of differential translocation in tolerance to glyphosate. Fourteen I. lacunosa accessions had GR50 values ranging from 58 to 151 grams of acid equivalent per hectare (ae/ha) glyphosate, a 2.6-fold variability in tolerance to glyphosate. There was no evidence of the most tolerant (MT) accession metabolizing glyphosate to AMPA more rapidly than the least tolerant (LT) accession. Metabolism to sarcosine was not found. (14)C-glyphosate absorption was similar in the two accessions. LT accession translocated more (14)C-glyphosate than MT accession at 24 and 48 h after treatment. Differential translocation partly explains glyphosate tolerance in MT accession.

  17. A sensitive film structure improvement of reduced graphene oxide based resistive gas sensors

    Science.gov (United States)

    Zhou, Yong; Xie, GuangZhong; Xie, Tao; Yuan, Huan; Tai, HuiLing; Jiang, YaDong; Chen, Zhi

    2014-07-01

    This study was focused on how to improve the gas sensing properties of resistive gas sensors based on reduced graphene oxide. Sol-airbrush technology was utilized to prepare reduced graphene oxide films using porous zinc oxide films as supporting materials mainly for carbon dioxide sensing applications. The proposed film structure improved the sensitivity and the response/recovery speed of the sensors compared to those of the conventional ones and alleviated the restrictions of sensors' performance to the film thickness. In addition, the fabrication technology is relatively simple and has potential for mass production in industry. The improvement in the sensitivity and the response/recovery speed is helpful for fast detection of toxic gases or vapors in environmental and industrial applications.

  18. STUDY OF CHRONIC TOXICITY OF THE GLYPHOSATE HERBICIDE IN SEEDS OF CORN,

    Directory of Open Access Journals (Sweden)

    Ana Cláudia Rebessi

    2011-07-01

    Full Text Available Glyphosate is an agrochemical from the group of phosphonates, which is widely used as a herbicide. Although it kills almost any plant, it can be used to eliminate weeds during the growth of crops that are resistant to glyphosate. This research aimed to evaluate the toxicological effects of the herbicide in a study using as test organism seeds of maize (Zea mays, okra (Abelmoschus esculentus (L. Moench and arugula (Eruca sativa. The toxicological testing was to use a paper towel dampened with a sample of glyphosate and twenty seeds evenly distributed in containers with lids, left in a dry and airy place, and watered once a day for 5 days. It was possible to check the toxic effect of glyphosate for corn seeds at concentrations above 90 mg.L-1, for okra seeds at concentrations above 75 mg L-1 and arugula seeds in concentrations above 2 mg L - 1. Thus it was concluded that the seeds studied showed a high sensitivity with the possibility to be applied in toxicity testing, representing a simple and low cost.

  19. Analysis of glyphosate and aminomethylphosphonic acid in water, plant materials and soil.

    Science.gov (United States)

    Koskinen, William C; Marek, LeEtta J; Hall, Kathleen E

    2016-03-01

    There is a need for simple, fast, efficient and sensitive methods of analysis for glyphosate and its degradate aminomethylphosphonic acid (AMPA) in diverse matrices such as water, plant materials and soil to facilitate environmental research needed to address the continuing concerns related to increasing glyphosate use. A variety of water-based solutions have been used to extract the chemicals from different matrices. Many methods require extensive sample preparation, including derivatization and clean-up, prior to analysis by a variety of detection techniques. This review summarizes methods used during the past 15 years for analysis of glyphosate and AMPA in water, plant materials and soil. The simplest methods use aqueous extraction of glyphosate and AMPA from plant materials and soil, no derivatization, solid-phase extraction (SPE) columns for clean-up, guard columns for separation and confirmation of the analytes by mass spectrometry and quantitation using isotope-labeled internal standards. They have levels of detection (LODs) below the regulatory limits in North America. These methods are discussed in more detail in the review. PMID:26454260

  20. ACQUIREMENT OF TRANSGENIC COTTON (GOSSYPIUM HIRSUTUM L. RESISTANT TO HERBICIDE AND INSECT USING GLYPHOSATE-TOLERANT aroAM12 GENE AS A SELECTABLE MARKER

    Directory of Open Access Journals (Sweden)

    Xie Longxu

    2005-08-01

    , was used as a dominant selectable marker for cotton plant transformation. The genes were introduced into commercial cultivar Zhongmian12 of cotton (Gossypium hirsutum L. by Agrobacterium-mediated transformation. The transformants were directly selected on medium supplemented with 80μmol/L glyphosate. In this research, 40 regenerative cotton plantlets were obtained through screening. Integration of aroAM12 and Bts1m genes was confirmed by PCR and Southern blot, the results indicated that all the 40 plants possessed the aroAM12 gene, 28 of which possessed both the aroAM12 and BtS1m genes. Expression of both the genes was established by Western blots. Insect bioassay and glyphosate resistance assay indicated that the transgenic cotton plants obtained were highly resistant to glyphosate and insect. The results of glyphosate resistance and insect bioassay of T1 generation showed that the numbers of resistance and sensitive phenotypes showed Mendelian segregation ratio.

  1. Characterization of glyphosate resistance in Amaranthus tuberculatus populations.

    Science.gov (United States)

    Lorentz, Lothar; Gaines, Todd A; Nissen, Scott J; Westra, Philip; Strek, Harry J; Dehne, Heinz W; Ruiz-Santaella, Juan Pedro; Beffa, Roland

    2014-08-13

    The evolution of glyphosate-resistant weeds has recently increased dramatically. Six suspected glyphosate-resistant Amaranthus tuberculatus populations were studied to confirm resistance and determine the resistance mechanism. Resistance was confirmed in greenhouse for all six populations with glyphosate resistance factors (R/S) between 5.2 and 7.5. No difference in glyphosate absorption or translocation was observed between resistant and susceptible individuals. No mutation at amino acid positions G101, T102, or P106 was detected in the EPSPS gene coding sequence, the target enzyme of glyphosate. Analysis of EPSPS gene copy number revealed that all glyphosate-resistant populations possessed increased EPSPS gene copy number, and this correlated with increased expression at both RNA and protein levels. EPSPS Vmax and Kcat values were more than doubled in resistant plants, indicating higher levels of catalytically active expressed EPSPS protein. EPSPS gene amplification is the main mechanism contributing to glyphosate resistance in the A. tuberculatus populations analyzed.

  2. Effect of glyphosate on reproductive organs in male rat.

    Science.gov (United States)

    Dai, Pengyuan; Hu, Ping; Tang, Juan; Li, Yansen; Li, Chunmei

    2016-06-01

    Glyphosate as an active ingredient of Roundup(®) which is thought to be one of the most popular herbicide was used worldwide. Many studies have focused on reproductive toxicity on glyphosate-based herbicide, but few evidence exists to imply the male reproductive toxicity of glyphosate alone in vivo. In this study SD rats were Lavaged with glyphosate at doses of 5, 50, 500mg/kg to detect the toxicity of glyphosate on rat testis. Glyphosate significantly decreased the average daily feed intake at dose of 50mg/kg, and the weight of seminal vesicle gland, coagulating gland as well as the total sperm count at dose of 500mg/kg. Immunohistochemistry of androgen receptor (AR) has no difference among all groups. As to testosterone, estradiol, progesterone and oxidative stress parameters, the level of them has no differences amidst all doses. Taken together, we conclude that glyphosate alone has low toxicity on male rats reproductive system. PMID:27286640

  3. Effect of glyphosate on reproductive organs in male rat.

    Science.gov (United States)

    Dai, Pengyuan; Hu, Ping; Tang, Juan; Li, Yansen; Li, Chunmei

    2016-06-01

    Glyphosate as an active ingredient of Roundup(®) which is thought to be one of the most popular herbicide was used worldwide. Many studies have focused on reproductive toxicity on glyphosate-based herbicide, but few evidence exists to imply the male reproductive toxicity of glyphosate alone in vivo. In this study SD rats were Lavaged with glyphosate at doses of 5, 50, 500mg/kg to detect the toxicity of glyphosate on rat testis. Glyphosate significantly decreased the average daily feed intake at dose of 50mg/kg, and the weight of seminal vesicle gland, coagulating gland as well as the total sperm count at dose of 500mg/kg. Immunohistochemistry of androgen receptor (AR) has no difference among all groups. As to testosterone, estradiol, progesterone and oxidative stress parameters, the level of them has no differences amidst all doses. Taken together, we conclude that glyphosate alone has low toxicity on male rats reproductive system.

  4. Cadmium adsorption in montmorillonite as affected by glyphosate

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-jun; ZHOU Dong-mei; LUO Xiao-san; SUN Rui-juan; CHEN Huai-man

    2004-01-01

    Behaviors of soil heavy metals are often affected by coexisting herbicides due to their physical and chemical interaction. Effect of glyphosate, an herbicide containing -PO32- and -COOH groups, on cadmium adsorption in montmorillonite was studied in detail. The results showed that cadmium adsorption quantity in montmorillonite increased with increasing soil solution pH and cadmium concentration as usual, but decreased with glyphosate, which is due to the formation of a low affinity complex of Cd and glyphosate and decreasing solution pH induced by glyphosate addition. When the equilibrium solution pH was below 6.7, glyphosate has little effect on cadmium adsorption, but when the equilibrium solution pH was above 6.7, glyphosate significantly decreased cadmium adsorption quantity in montmorillonite. In addition, the adding order of Cd and glyphosate also influenced Cd adsorption quantity in montmorillonite.

  5. 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.

    Science.gov (United States)

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

    2013-08-01

    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. Exposure 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.

  6. Low-cost reduced graphene oxide-based conductometric nitrogen dioxide-sensitive sensor on paper.

    Science.gov (United States)

    Hassinen, Jukka; Kauppila, Jussi; Leiro, Jarkko; Määttänen, Anni; Ihalainen, Petri; Peltonen, Jouko; Lukkari, Jukka

    2013-04-01

    The fabrication concept for a low-cost sensor device using reduced graphene oxide (rGO) as the sensing material on a porous paper substrate is presented. The sensors were characterized using conductivity and capacitance measurements, atomic force microscopy and X-ray photoelectron spectroscopy. The effects of different reducing agents, graphene oxide (GO) flake size and film thickness were studied. The sensor was sensitive to NO2, and devices based on a thin (10-nm) hydrazine-reduced GO layer had the best sensitivity, reaching a 70% reduction in resistance after 10 min of exposure to 10 ppm NO2. The sensitivity was high enough for the detection of sub-parts per million levels of NO2. Desorption of gas molecules, i.e. the recovery of the sensor, could be accelerated by UV irradiation. The structure and preparation of the sensor are simple and up-scalable, allowing their fabrication in bulk quantities, and the fabrication concept can be applied to other materials, too. PMID:23462978

  7. 草甘膦对土壤微生物的影响%Effects of glyphosate on soil microorganisms

    Institute of Scientific and Technical Information of China (English)

    陶波; 蒋凌雪; 沈晓峰; 栾凤侠; 邱丽娟

    2011-01-01

    Black soil in northeast region of China was used to investigate the effects of glyphosate on soil respiration, soil cultural bacteria, Rhizobium japonicum and Fusarium oxysporum, to provide a theoretical basis for the evaluation of environmental safety of glyphosate. The results showed that increasing glyphosate concentration increased the inhibition on soil respiration. When glyphosate concentration in soil were ling · kg-1 , 10mg · kg-1 and 100 mg · kg-1 , the risk index were 1.20, 0. 322 and 0.076, which were less than the standard index of 20.Glyphosate influenced quantities of soil fungi and actinomycetes. High glyphosate concentration increased the inhibition to population of soil cultural bacteria. With the extended application of glyphosate, soil fungus, bacteria and actinomycetes populations had been restored. Actinomycetes were more sensitive to glyphosate than fungus and bacteria, and soil bacteria had a strong tolerance or degrading ability to glyphosate. Glyphosate impacted on inhibiting Rhizobium japonicum and Fusarium oxysporum, and the inhibition of Rhizobium japonicum was in direct proportion with the concentration of glyphosate. Low glyphosate concentration promoted Fusarium oxysporum populations,while high concentration inhibited them. The extended application time of glyphosate decreased the inhibition of glyphosate on Rhizobium japonicum and Fusarium oxysporum.%以东北地区黑土为材料,探讨草甘膦对土壤呼吸、土壤可培养菌种群数量、大豆固氮根瘤菌和大豆根腐镰刀菌数量的影响.研究结果表明,随着草甘膦浓度的加大,土壤呼吸的抑制作用增强,土壤中草甘膦含量为1mg·kg-1、10mg·kg-1、100mg·kg-1时,危害系数分别为1.20、0.322、0.076,远小于无危害标准系数20,确定草甘膦对土壤微生物低毒或无实际危害.不同浓度的草甘膦对土壤真菌、放线菌种群数量具有一定影响.土壤可培养菌种群数量随草甘膦浓度的升高抑制作

  8. 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

  9. 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...

  10. 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.

  11. Intra-Articular Corticosteroids in Addition to Exercise for Reducing Pain Sensitivity in Knee Osteoarthritis

    DEFF Research Database (Denmark)

    Soriano-Maldonado, Alberto; Klokker, Louise; Bartholdy, Cecilie;

    2016-01-01

    OBJECTIVE: To assess the effects of one intra-articular corticosteroid injection two weeks prior to an exercise-based intervention program for reducing pain sensitivity in patients with knee osteoarthritis (OA). DESIGN: Randomized, masked, parallel, placebo-controlled trial involving 100 particip......OBJECTIVE: To assess the effects of one intra-articular corticosteroid injection two weeks prior to an exercise-based intervention program for reducing pain sensitivity in patients with knee osteoarthritis (OA). DESIGN: Randomized, masked, parallel, placebo-controlled trial involving 100...... the injections all participants undertook a 12-week supervised exercise program. Main outcomes were changes from baseline in pressure-pain sensitivity (pressure-pain threshold [PPT] and temporal summation [TS]) assessed using cuff pressure algometry on the calf. These were exploratory outcomes from a...... analyzed. The mean group difference in changes from baseline at week 14 was 0.6 kPa (95% CI: -1.7 to 2.8; P = 0.626) for PPT and 384 mm×sec (95% CI: -2980 to 3750; P = 0.821) for TS. CONCLUSIONS: These results suggest that adding intra-articular corticosteroid injection 2 weeks prior to an exercise program...

  12. Glyphosate in Runoff Waters and in the Root-Zone: A Review

    OpenAIRE

    Lyndsay E. Saunders; Reza Pezeshki

    2015-01-01

    Glyphosate is the most commonly-used herbicide in the world. The present review summarizes the discovery, prevalence, chemical and physical properties, mode of action and effects in plants, glyphosate resistance and the environmental fate of glyphosate. Numerous studies are reviewed that demonstrate that glyphosate may run off of fields where it is applied, while other studies provide evidence that plant roots can take up glyphosate. Non-target vegetation may be exposed to glyphosate in the r...

  13. 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

  14. 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...

  15. Glyphosate fate in soils when arriving in plant residues.

    Science.gov (United States)

    Mamy, Laure; Barriuso, Enrique; Gabrielle, Benoît

    2016-07-01

    A significant fraction of pesticides sprayed on crops may be returned to soils via plant residues, but its fate has been little documented. The objective of this work was to study the fate of glyphosate associated to plants residues. Oilseed rape was used as model plant using two lines: a glyphosate-tolerant (GT) line and a non-GT one, considered as a crucifer weed. The effects of different fragmentation degrees and placements in soil of plant residues were tested. A control was set up by spraying glyphosate directly on the soil. The mineralization of glyphosate in soil was slower when incorporated into plant residues, and the amounts of extractable and non-extractable glyphosate residues increased. Glyphosate availability for mineralization increased when the size of plant residues decreased, and as the distribution of plant residues in soil was more homogeneous. After 80 days of soil incubation, extractable (14)C-residues mostly involved one metabolite of glyphosate (AMPA) but up to 2.6% of initial (14)C was still extracted from undecayed leaves as glyphosate. Thus, the trapping of herbicides in plant materials provided a protection against degradation, and crops residues returns may increase the persistence of glyphosate in soils. This pattern appeared more pronounced for GT crops, which accumulated more non-degraded glyphosate in their tissues.

  16. Glyphosate fate in soils when arriving in plant residues.

    Science.gov (United States)

    Mamy, Laure; Barriuso, Enrique; Gabrielle, Benoît

    2016-07-01

    A significant fraction of pesticides sprayed on crops may be returned to soils via plant residues, but its fate has been little documented. The objective of this work was to study the fate of glyphosate associated to plants residues. Oilseed rape was used as model plant using two lines: a glyphosate-tolerant (GT) line and a non-GT one, considered as a crucifer weed. The effects of different fragmentation degrees and placements in soil of plant residues were tested. A control was set up by spraying glyphosate directly on the soil. The mineralization of glyphosate in soil was slower when incorporated into plant residues, and the amounts of extractable and non-extractable glyphosate residues increased. Glyphosate availability for mineralization increased when the size of plant residues decreased, and as the distribution of plant residues in soil was more homogeneous. After 80 days of soil incubation, extractable (14)C-residues mostly involved one metabolite of glyphosate (AMPA) but up to 2.6% of initial (14)C was still extracted from undecayed leaves as glyphosate. Thus, the trapping of herbicides in plant materials provided a protection against degradation, and crops residues returns may increase the persistence of glyphosate in soils. This pattern appeared more pronounced for GT crops, which accumulated more non-degraded glyphosate in their tissues. PMID:27077537

  17. Photomultiplier circuit including means for rapidly reducing the sensitivity thereof. [and protection from radiation damage

    Science.gov (United States)

    Mcclenahan, J. O. (Inventor)

    1974-01-01

    A simple, reliable and inexpensive control circuit is described for rapidly reducing the bias voltage across one or more of the dynode stages of a photomultiplier, to substantially decrease its sensitivity to incoming light at those times where excess light intensity might damage the tube. The control circuit comprises a switching device, such as a silicon controlled rectifier (SCR), coupled between a pair of the electrodes in the tube, preferably the cathode and first dynode, or the first and second dynodes, the switching device operating in response to a trigger pulse applied to its gate to short circuit the two electrodes. To insure the desired reduction in sensitivity, two switching stages, the devices be employed between two of the electrode stages, the devices being operated simultaneously to short circuit both stages.

  18. Cow milk allergy symptoms are reduced in mice fed dietary synbiotics during oral sensitization with whey.

    Science.gov (United States)

    Schouten, Bastiaan; van Esch, Betty C A M; Hofman, Gerard A; van Doorn, Suzan A C M; Knol, Jan; Nauta, Alma J; Garssen, Johan; Willemsen, Linette E M; Knippels, Léon M J

    2009-07-01

    Cow milk allergy is the most common food allergy in children. So far, no effective treatment is available to prevent or cure food allergy. The purpose of this study was to compare effects of dietary supplementation with a prebiotic mixture (Immunofortis), a probiotic strain [Bifidobacterium breve M-16V], or a synbiotic diet combining both on the outcome of the allergic response when provided during oral sensitization with whey in mice. Mice were fed diets containing 2% (wt:wt) Immunofortis and/or the B. breve M-16V (n = 6/group). The acute allergic skin response was determined by measuring ear swelling. Antigen-induced anaphylaxis was scored. Furthermore, whey-specific serum immunoglobulins and mouse mast cell protease-1 (mMCP-1) were determined. In mice fed the synbiotic mixture, the allergic skin response and the anaphylactic reaction were strongly reduced compared with whey-sensitized mice fed the control diet (P food allergens. PMID:19474160

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

    Science.gov (United States)

    Hu, Nantao; Yang, Zhi; Wang, Yanyan; Zhang, Liling; Wang, Ying; Huang, Xiaolu; Wei, Hao; Wei, Liangmin; Zhang, Yafei

    2014-01-01

    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.

  20. Herança da resistência de azevém (Lolium multiflorum ao glyphosate Inheritance of azevém (Lolium multiflorum resistance to glyphosate

    Directory of Open Access Journals (Sweden)

    L. Vargas

    2007-09-01

    Full Text Available O glyphosate é o principal produto usado para manejo não-seletivo das plantas daninhas. Já foram identificados biótipos de azevém resistentes a esse herbicida no Rio Grande do Sul, os quais estão se tornando predominantes rapidamente. Objetivou-se neste trabalho identificar o tipo de herança, o número de genes que conferem resistência e o grau de resistência dos biótipos homozigotos e heterozigotos resistentes em azevém. Foram realizados cruzamentos recíprocos entre genitores suscetíveis e resistentes para obtenção de sementes F1 e, em seguida, efetuaram-se os retrocruzamentos resistente e sensível. Plantas F1 foram cruzadas, para obtenção da geração F2. Sobre as plantas F1, F2, RCr e RCs e genitores foi aplicado o glyphosate na dose de 720 g ha-1, para avaliar a segregação. A fim de avaliar o grau de resistência, as plantas F1 e os genitores resistente e sensível foram tratados com doses crescentes de glyphosate (0, 360, 720, 1.440 e 2.880 g ha-1. As plantas F1 evidenciaram resposta intermediária ao biótipo resistente e sensível, demonstrando que a interação alélica é do tipo dominância incompleta. As plantas F2 mostraram tendência para segregação 3:1, indicando que a característica resistência ao glyphosate é controlada por um gene semidominante.Glyphosate is a non-selective herbicide used to control weeds. Azevem plants, which are tolerant to glyphosate, have been identified in Rio Grande do Sul, where they are rapidly becoming predominant. The objective of this work was to identify inheritance type, number of genes conferring resistance, and the degree of resistance in azevem plants. Reciprocal crossings between sensitive and resistant plants have been carried out to obtain F1 seeds which were crossed among themselves to obtain F2 plants .Herbicide containing 720 g ha-1 was applied on the F1, F2, RCr, Rc and parent plants to estimate segregation. To evaluate the degree of resistance of the F1 plants

  1. Mutants in Drosophila TRPC channels reduce olfactory sensitivity to carbon dioxide.

    Directory of Open Access Journals (Sweden)

    Farhath Badsha

    Full Text Available BACKGROUND: Members of the canonical Transient Receptor Potential (TRPC class of cationic channels function downstream of Gαq and PLCβ in Drosophila photoreceptors for transducing visual stimuli. Gαq has recently been implicated in olfactory sensing of carbon dioxide (CO(2 and other odorants. Here we investigated the role of PLCβ and TRPC channels for sensing CO(2 in Drosophila. METHODOLOGY/PRINCIPAL FINDINGS: Through behavioral assays it was demonstrated that Drosophila mutants for plc21c, trp and trpl have a reduced sensitivity for CO(2. Immuno-histochemical staining for TRP, TRPL and TRPγ indicates that all three channels are expressed in Drosophila antennae including the sensory neurons that express CO(2 receptors. Electrophysiological recordings obtained from the antennae of protein null alleles of TRP (trp(343 and TRPL (trpl(302, showed that the sensory response to multiple concentrations of CO(2 was reduced. However, trpl(302; trp(343 double mutants still have a residual response to CO(2. Down-regulation of TRPC channels specifically in CO(2 sensing olfactory neurons reduced the response to CO(2 and this reduction was obtained even upon down-regulation of the TRPCs in adult olfactory sensory neurons. Thus the reduced response to CO(2 obtained from the antennae of TRPC RNAi strains is not due to a developmental defect. CONCLUSION: These observations show that reduction in TRPC channel function significantly reduces the sensitivity of the olfactory response to CO(2 concentrations of 5% or less in adult Drosophila. It is possible that the CO(2 receptors Gr63a and Gr21a activate the TRPC channels through Gαq and PLC21C.

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

    DEFF Research Database (Denmark)

    Pedersen, Thomas; Fragiacomo, Giulio; Hansen, Ole;

    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 sens...... 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....

  3. Rydberg atoms with a reduced sensitivity to dc and low-frequency electric fields

    CERN Document Server

    Jones, L A; Martin, J D D

    2013-01-01

    A non-resonant microwave dressing field at 38.465 GHz was used to eliminate the static electric dipole moment difference between the $49s_{1/2}$ and $48s_{1/2}$ Rydberg states of $^{87}$Rb in dc fields of approximately 1 V/cm. The reduced susceptibility to electric field fluctuations was measured using 2-photon microwave spectroscopy. An anomalous spectral doublet is attributed to polarization ellipticity in the dressing field. The demonstrated ability to inhibit static dipole moment differences --- while retaining sensitivity to high frequency fields --- is applicable to sensors and/or quantum devices using Rydberg atoms.

  4. 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... COMMISSION Glyphosate From China AGENCY: United States International Trade Commission. ACTION: Institution...

  5. 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...

  6. RHIZOSPHERE ECOLOGY AND GLYPHOSATE-RESISTANT SOYBEAN

    Science.gov (United States)

    The interaction of glyphosate-resistant (GR) soybean with the ecology of plant-associated microbial populations has been the subject of environmental assessments in response to the public concern regarding the ecological compatibility of transgenic crops. Changes in the dynamics of soil and rhizosph...

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

    Directory of Open Access Journals (Sweden)

    J.M. Paula

    2011-03-01

    Full Text Available 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. Os resultados evidenciaram que a população de C. bonariensis é maior em áreas mantidas sem cultivo (pousio do que naquelas áreas cultivadas com trigo ou aveia-preta durante o inverno. Observou-se que o trigo e a aveia-preta exercem efeito supressor sobre a população de C. bonariensis, proporcionando maior facilidade de controle com herbicida na pré-semeadura da cultura usada em sucessão. O controle de C. bonariensis resistente ao herbicida glyphosate foi satisfatório quando se utilizaram herbicidas pós-emergentes na cultura do trigo e glyphosate + 2,4-D ou glyphosate + diuron + paraquat na pré-semeadura da soja.Horseweed (Conyza bonariensis, which belongs to the Asteraceae family, is a weed species widely spread in Brazil. Horseweed biotypes resistant to glyphosate, the main herbicide used in Roundup Ready soybean fields, were identified in the states of Rio Grande do Sul and Parana. The aim of this study was to evaluate the effect of different winter and pre-sowing management techniques on soybean plant population of C. bonariensis resistant to glyphosate. The results showed that the population of C. bonariensis is larger in areas maintained fallow than in areas planted with wheat or oats during the winter. Wheat and oats were found to exert a suppressive effect on the population of C. bonariensis, providing greater ease of control with herbicide before seeding in the culture used in succession. The control of glyphosate-resistant C

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

    Directory of Open Access Journals (Sweden)

    E.S. Roman

    2004-06-01

    for sowing wheat under no-till system. The experimental design was a completely randomized design for the greenhouse experiment and a completely randomized block design for the field experiment. Herbicides with different mechanisms of action were evaluated on the weed control: glyphosate, glufosinate, clethodim, haloxyfop-r and diclofop, paraquat and paraquat+diuron. The results obtained under greenhouse conditions indicated the glyphosate susceptible biotype was controlled by the rate of 360 g e.a. ha-1. The resistant ryegrass biotype had no reduction in dry matter production and less than 15 % phytotoxicity caused by glyphosate up to 1,440 g e.a. ha-1. However, glyphosate rates between 1440 and 5,760 g e.a. ha-1 reduced dry matter accumulation and resulted in toxicities under45%. Under field conditions, the best Lolium multiflorum control was given by clethodim 79.2 g ha-1 and diuron + paraquat at 300+600 g ha¹, respectively. The results obtained in these studies indicated that the population was composed predominantly by a biotype resistant to EPSPs inhibitor herbicides.

  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

    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. Reduced stretch-reflex sensitivity after exhausting stretch-shortening cycle exercise.

    Science.gov (United States)

    Nicol, C; Komi, P V; Horita, T; Kyröläinen, H; Takala, T E

    1996-01-01

    The stretch-shortening cycle (SSC) is an effective and natural form of muscle function but, when repeated with sufficient intensity or duration, it may lead to muscle damage and functional defects. A reduced tolerance to impact has been reported, which may be partly attributed to a reduced stretch-reflex potentiation. The aim of the present study was to examine the influence of SSC-induced metabolic fatigue and muscle damage on the efficacy of stretch reflexes, as judged by the electromyograph (EMG) response of two shank muscles (lateral gastrocnemius LG, soleus SOL) to controlled ramp stretches. These EMG responses were recorded before and immediately after exhausting SSC-type leg exercise and 2 h, 2 days and 4 days later. Serum concentrations of creatine kinase ([CK]), myoglobin and lactate were measured repetitively along the protocol. Two maximal vertical drop jumps and counter-movement jumps were performed after each reflex test. The exhausting SSC-type exercise induced an immediate reduction (P drop jump performance remained slightly but significantly reduced (P drop jump height. Furthermore, a significant relationship (P < 0.05) was found between recovery of the stretch reflex in LG and the decrease of [CK] between the 2nd and the 4th day. These findings support the hypothesis of a reduced stretch-reflex sensitivity. While the exact mechanisms of the reflex inhibition remain unclear, it is emphasized that the delayed recovery of the reflex sensitivity could have resulted from the progressive inflammation that develops in cases of muscle damage. PMID:8925809

  11. The Research on the Quality Control of Nitro Glyphosate of Glyphosate TC%草甘膦原药中亚硝基草甘膦的质量控制研究

    Institute of Scientific and Technical Information of China (English)

    蔡黎克; 周玉良; 杨新东

    2012-01-01

    By using optimization method,depending on the production process of glyphosate TC detection analysis,different production processes between the nitroso glyphosate content differences were found out,and through the process of adjustment to reduce the product of nitroso glyphosate content,the quality of the products was improved effectively.%通过运用优化的方法,对不同生产工艺的草甘膦原药进行检测分析,找出了不同生产工艺间亚硝基草甘膦含量的差异,并通过对工艺的调整降低了草甘膦原药中亚硝基草甘膦的含量,有效提高了产品的质量

  12. Development of highly glyphosate-tolerant tobacco by coexpression of glyphosate acetyltransferase gat and EPSPS G2-aroA genes

    OpenAIRE

    Baoqing Dun; Xujing Wang; Wei Lu; Ming Chen; Wei Zhang; Shuzhen Ping; Zhixing Wang; Baoming Zhang; Min Lin

    2014-01-01

    The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). Glyphosate acetyltransferase (GAT) effectively detoxifies glyphosate by N-acetylation. With the aim of identifying a new strategy for development of glyphosate-tolerant crops, the plant expression vector pG2-GAT harboring gat and G2-aroA (encoding EPSPS) has been transformed into tobacco (Nicotiana tabacum) to develop novel plants with higher tolerance to glyphosate. Results from Southern and Wes...

  13. 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.

  14. Side-effects of glyphosate on the life parameters of Eriopis connexa (Coleoptera: Coccinelidae) in Argentina.

    Science.gov (United States)

    Mirande, L; Haramboure, M; Smagghe, G; Piñeda, S; Schneider, M I

    2010-01-01

    In Argentina, transgenic soybean crop (Roundup Ready, RR) has undergone a major expansion over the last 15 years, with the consequent increase of glyphosate applications, a broad-spectrum and post emergence herbicide. Soybean crops are inhabited by several arthropods. Eriopis connexa Germar (Coleoptera: Coccinelidae) is a predator associated to soybean soft-bodies pest and have a Neotropical distribution. Nowadays, it is being considered a potentially biological control agent in South America. The objectives of this work were to evaluate the side-effects of glyphosate on larvae (third instar) and adults of this predator. Commercial compound and the maximum registered concentrations for field use were employed: GlifoGlex 48 (48% glyphosate, 192 mg a.i./litre, Gleba Argentina S.A.). The exposure was by ingestion through the treated prey (Rophalosiphum padi) or by drinking treated water during 48 h for treatment of the adult. The herbicide solutions were prepared using distilled water as solvent. The bioassays were carried out in the laboratory under controlled conditions: 23 +/- 0.5 degrees C, 75 +/- 5% RH and 16:8 (L:D) of photoperiod. Development time, weight of pupae, adult emergence, pre-oviposition period, fecundity and fertility were evaluated as endpoints. Larvae from glyphosate treatment molted earlier than controls. In addition, the weight of pupae, longevity, fecundity and fertility were drastically reduced in treated organisms. The reductions were more drastic when the treatments were performed at the third larval stage than as adult. The reproduction capacity of the predator was the most affected parameter and could be related to a hormonal disruption by glyphosate in the treated organisms. This work can confirm the deleterious effects of this herbicide on beneficial organisms. Also, it agrees with prior studies carried out on other predators associated to soybean pest, such as Chrysoperla externa (Neuroptera: Chrysopidae) and Alpaida veniliae (Araneae

  15. Differential response of two sourgrass populations to glyphosate

    Directory of Open Access Journals (Sweden)

    São Paulo State University, Jaboticabal, SP, Brazil

    2013-02-01

    Full Text Available 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 (0D, D/16, D/8, D/4, D/2, D, 2D, 4D, 8D, and 16D; so that D is the dose of 1.08 kg e.a. ha-1. The treatments were sprayed when the plants had shown 3-5 tillers. The population collected in the nonagricultural area was slightly more sensible to the herbicide glyphosate than the population originated from an area where the herbicide application is common, not indicating glyphosate resistance.

  16. 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.

  17. Reduced gravitropic sensitivity in roots of a starch-deficient mutant of Nicotiana sylvestris

    Science.gov (United States)

    Kiss, J. Z.; Sack, F. D.

    1989-01-01

    Gravitropism was studied in seedlings of Nicotiana sylvestris Speg. et Comes wild-type (WT) and mutant NS 458 which has a defective plastid phosphoglucomutase (EC 2.7.5.1.). Starch was greatly reduced in NS 458 compared to the WT, but small amounts of starch were detected in rootcap columella cells in NS 458 by light and electron microscopy. The roots of WT are more sensitive to gravity than mutant NS 458 roots since: (1) in mutant roots, curvature was reduced and delayed in the time course of curvature; (2) curvature of mutant roots was 24-56% that of WT roots over the range of induction periods tested; (3) in intermittent-stimulation experiments, curvature of mutant roots was 37% or less than that of WT roots in all treatments tested. The perception time, determined by intermittent-stimulation experiments, was Planta 177, 198-206) support the conclusions that a full complement of starch is necessary for full gravitropic sensitivity and that amyloplasts function in gravity perception. Since a presumed relatively small increase in plastid buoyant mass (N. sylvestris mutant versus Arabidopsis mutant) significantly improves the orientation of the N. sylvestris mutant roots, we suggest that plastids are the likeliest candidates to be triggering gravity perception in roots of both mutants.

  18. Reduced Sensitivity to Sooner Reward During Intertemporal Decision-Making Following Insula Damage in Humans

    Science.gov (United States)

    Sellitto, Manuela; Ciaramelli, Elisa; Mattioli, Flavia; di Pellegrino, Giuseppe

    2016-01-01

    During intertemporal choice, humans tend to prefer small-sooner rewards over larger-delayed rewards, reflecting temporal discounting (TD) of delayed outcomes. Functional neuroimaging (fMRI) evidence has implicated the insular cortex in time-sensitive decisions, yet it is not clear whether activity in this brain region is crucial for, or merely associated with, TD behavior. Here, patients with damage to the insula (Insular patients), control patients with lesions outside the insula, and healthy individuals chose between smaller-sooner and larger-later monetary rewards. Insular patients were less sensitive to sooner rewards than were the control groups, exhibiting reduced TD. A Voxel-based Lesion-Symptom Mapping (VLSM) analysis confirmed a statistically significant association between insular damage and reduced TD. These results indicate that the insular cortex is crucial for intertemporal choice. We suggest that he insula may be necessary to anticipate the bodily/emotional effects of receiving rewards at different delays, influencing the computation of their incentive value. Devoid of such input, insular patients’ choices would be governed by a heuristic of quantity, allowing patients to wait for larger options. PMID:26793084

  19. Reduced sensitivity to sooner reward during intertemporal decision-making following insula damage in humans

    Directory of Open Access Journals (Sweden)

    Manuela eSellitto

    2016-01-01

    Full Text Available During intertemporal choice, humans tend to prefer small-sooner rewards over larger-delayed rewards, reflecting temporal discounting (TD of delayed outcomes. Functional neuroimaging evidence has implicated the insular cortex in time-sensitive decisions, yet it is not clear whether activity in this brain region is crucial for, or merely associated with, TD behaviour. Here, patients with damage to the insula (Insular patients, control patients with lesions outside the insula, and healthy individuals chose between smaller-sooner and larger-later monetary rewards. Insular patients were less sensitive to sooner rewards than were the control groups, exhibiting reduced TD. A Voxel-based Lesion-Symptom Mapping (VLSM analysis confirmed a statistically significant association between insular damage and reduced TD. These results indicate that the insular cortex is crucial for intertemporal choice. We suggest that he insula may be necessary to anticipate the bodily/emotional effects of receiving rewards at different delays, influencing the computation of their incentive value. Devoid of such input, insular patients’ choices would be governed by a heuristic of quantity, allowing patients to wait for larger options.

  20. 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

  1. Identification of glyphosate resistance in Lolium rigidum Gaudin

    OpenAIRE

    Danijela Pavlović; Charlie Reinhardt; Igor Elezović; Sava Vrbničanin

    2011-01-01

    Glyphosate resistance was found in Lolium rigidum Gaudin (Rigid ryegrass, LOLRI) in South Africa. Suspected glyphosate-resistant L. rigidum populations were collected and grown under greenhouse conditions. The plants were sprayed with a range of doses of glyphosate 35 days after planting and shoot dry biomass was determined 17 days after herbicide treatment. Based on the dose-response experiment conducted in the greenhouse, one population of L. rigidum susp...

  2. Comparison of Torpedograss and Pickerelweed Susceptibility to Glyphosate

    OpenAIRE

    Gettys, Lyn A.; Sutton, David L.

    2004-01-01

    Torpedograss (Panicum repens L.) is one of the most invasive exotic plants in aquatic systems. Repeat applications of (N-phosphonomethyl) glycine (glyphosate) herbicides provide limited control of torpedograss; unfortunately, glyphosate often negatively impacts most non-target native species that grow alongside the weed. This experiment studied the effect of glyphosate on pickerelweed (Pontederia cordata L.), a native plant that shares habitats with torpedograss. Actively gr...

  3. Exploring the effects of glyphosate products on weed composition

    OpenAIRE

    Koning, Laurie Anne; Sefzat, David; Gerowitt, Bärbel

    2016-01-01

    Glyphosate is a non-selective, broad-spectrum, systematic herbicide that is the world’s most widely used herbicide since its introduction in the 1970s as a pre-plant, post-directed and post-harvest herbicide application with further technological developments leading to its use within glyphosate resistant crops (GRCs) as of the 1990s. In countries around the world, weed shifts have accompanied weed management systems employing glyphosate products. The farmer actions and weed reactions that ha...

  4. 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...

  5. 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...

  6. Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate

    OpenAIRE

    Wang, Cong; Lin, Xin; Li, Ling; Lin, Senjie

    2016-01-01

    Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P) nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta). Based on growth responses to different concentrations of glyphosate under contrasting dissolv...

  7. What Constitutes a "Good" Sensitivity Analysis? Elements and Tools for a Robust Sensitivity Analysis with Reduced Computational Cost

    Science.gov (United States)

    Razavi, Saman; Gupta, Hoshin; Haghnegahdar, Amin

    2016-04-01

    Global sensitivity analysis (GSA) is a systems theoretic approach to characterizing the overall (average) sensitivity of one or more model responses across the factor space, by attributing the variability of those responses to different controlling (but uncertain) factors (e.g., model parameters, forcings, and boundary and initial conditions). GSA can be very helpful to improve the credibility and utility of Earth and Environmental System Models (EESMs), as these models are continually growing in complexity and dimensionality with continuous advances in understanding and computing power. However, conventional approaches to GSA suffer from (1) an ambiguous characterization of sensitivity, and (2) poor computational efficiency, particularly as the problem dimension grows. Here, we identify several important sensitivity-related characteristics of response surfaces that must be considered when investigating and interpreting the ''global sensitivity'' of a model response (e.g., a metric of model performance) to its parameters/factors. Accordingly, we present a new and general sensitivity and uncertainty analysis framework, Variogram Analysis of Response Surfaces (VARS), based on an analogy to 'variogram analysis', that characterizes a comprehensive spectrum of information on sensitivity. We prove, theoretically, that Morris (derivative-based) and Sobol (variance-based) methods and their extensions are special cases of VARS, and that their SA indices are contained within the VARS framework. We also present a practical strategy for the application of VARS to real-world problems, called STAR-VARS, including a new sampling strategy, called "star-based sampling". Our results across several case studies show the STAR-VARS approach to provide reliable and stable assessments of "global" sensitivity, while being at least 1-2 orders of magnitude more efficient than the benchmark Morris and Sobol approaches.

  8. Impact of multiple anthropogenic stressors on freshwater: how do glyphosate and the invasive mussel Limnoperna fortunei affect microbial communities and water quality?

    Science.gov (United States)

    Pizarro, Haydée; Di Fiori, Eugenia; Sinistro, Rodrigo; Ramírez, Marina; Rodríguez, Patricia; Vinocur, Alicia; Cataldo, Daniel

    2016-01-01

    The study of the joint effect of multiple anthropogenic stressors is important because the emerging consequences are often unpredictable on the basis of knowledge of single effects. We explored the joint impact of glyphosate and the invasive golden mussel Limnoperna fortunei on freshwater phytoplankton, bacterioplankton and periphyton, and on the physical and chemical properties of the water. We manipulated both stressors simultaneously in a 25-day experiment using outdoor mesocosms; we assayed technical-grade glyphosate acid at four concentrations: 0, 1, 3 and 6 mg gly L(−1) under scenarios with and without mussels. The addition of the glyphosate significantly increased total phosphorus according to the concentration used; the high clearance rate of L. fortunei significantly decreased phytoplanktonic abundance leading to low values of turbidity. The mussel significantly stimulated the development of filamentous green algae (metaphyton). Interestingly, the combined effect revealed that L. fortunei accelerated the dissipation of glyphosate, which showed a 4-fold decrease in its half-life; this promoted the rapid bioavailability of glyphosate-derived phosphorus in the water. The interaction had a synergistic effect on soluble reactive phosphorus concentrations and was directly dependent on the concentration of glyphosate. A synergistic effect was also observed on bacterioplankton, water turbidity and metaphyton, thus inducing enhanced and rapid eutrophication. The ability of mussels to reduce glyphosate in water may be valued as positive, but our results allow us to predict that the invasion of Limnoperna fortunei in natural freshwater systems contaminated by glyphosate will accelerate the negative impact of the herbicide associated with eutrophication.

  9. Expectancy of stress-reducing aromatherapy effect and performance on a stress-sensitive cognitive task.

    Science.gov (United States)

    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 groups (active experimental, detectable, and undetectable placebo) and 2 prime subgroups (prime suggesting stress-reducing aroma effects or no-prime). GNG performance, ERPs, subjective expected aroma effects, and stress ratings were assessed at baseline and poststress. Results. No specific aroma effects on stress or cognition were observed. However, regardless of experienced aroma, people receiving a prime displayed faster poststress median reaction times than those receiving no prime. A significant interaction for N200 amplitude indicated divergent ERP patterns between baseline and poststress for go and no-go stimuli depending on the prime subgroup. Furthermore, trends for beneficial prime effects were shown on poststress no-go N200/P300 latencies and N200 amplitude. Conclusion. While there were no aroma-specific effects on stress or cognition, these results highlight the role of expectancy for poststress response inhibition and attention. PMID:25802539

  10. Characteristics of thermally reduced graphene oxide and applied for dye-sensitized solar cell counter electrode

    Science.gov (United States)

    Ho, Ching-Yuan; Wang, Hong-Wen

    2015-12-01

    Graphene oxide (GO) was synthesized from a flake-type of graphite powder, which was then reduced to a few layers of graphene sheets using the thermal reduction method. The surface morphology, phase crystallization, and defect states of the reduced graphene were determined from an electron microscope equipped with an energy dispersion spectrometer, X-ray diffraction, Raman spectroscopy, and infrared spectra. After graphene formation, the intercalated defects that existed in the GO were removed, and it became crystalline by observing impurity changes and d-spacing. Dye-sensitized solar cells, using reduced graphene as the counter electrode, were fabricated to evaluate the electrolyte activity and charge transport performance. The electrochemical impedance spectra showed that increasing the thermal reduction temperature could achieve faster electron transport and longer electron lifetime, and result in an energy conversion efficiency of approximately 3.4%. Compared to the Pt counter electrode, the low cost of the thermal reduction method suggests that graphene will enjoy a wide range of potential applications in the field of electronic devices.

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

    Directory of Open Access Journals (Sweden)

    Irina Chamine

    2015-01-01

    Full Text Available 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 groups (active experimental, detectable, and undetectable placebo and 2 prime subgroups (prime suggesting stress-reducing aroma effects or no-prime. GNG performance, ERPs, subjective expected aroma effects, and stress ratings were assessed at baseline and poststress. Results. No specific aroma effects on stress or cognition were observed. However, regardless of experienced aroma, people receiving a prime displayed faster poststress median reaction times than those receiving no prime. A significant interaction for N200 amplitude indicated divergent ERP patterns between baseline and poststress for go and no-go stimuli depending on the prime subgroup. Furthermore, trends for beneficial prime effects were shown on poststress no-go N200/P300 latencies and N200 amplitude. Conclusion. While there were no aroma-specific effects on stress or cognition, these results highlight the role of expectancy for poststress response inhibition and attention.

  12. 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 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.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 μg a

  13. 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 efic

  14. Massive Preparation of Reduced-Sensitivity Nano CL-20 and Its Characterization

    Science.gov (United States)

    Guo, Xiaode; Ouyang, Gang; Liu, Jie; Li, Qing; Wang, Longxiang; Gu, Zhiming; Li, Fengsheng

    2015-01-01

    Nano 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) was produced massively by ball milling. One thousand grams of the raw CL-20 were used per batch. The product was characterized using laser granularity measurement, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). The results show that the pulverized particles were pseudo-spheres with an average particle size (d50) of 200 nm, and the thermal decomposition peak temperature of the nano CL-20 was 239.61°C lower than that of the micrometer-sized CL-20 at a heating rate of 15°C . min-1. Furthermore, compared with the raw CL-20, the impact and friction sensitivities of the nano CL-20 were considerably reduced by 116.2 and 22%, respectively, indicating the great improvement in safety of CL-20.

  15. Reducing the phase sensitivity of laser-based optical reservoir computing systems.

    Science.gov (United States)

    Nguimdo, Romain Modeste; Verschaffelt, Guy; Danckaert, Jan; Van der Sande, Guy

    2016-01-25

    Optical implementations of reservoir computing systems are very promising because of their high processing speeds and the possibility to process several tasks in parallel. These systems can be implemented using semiconductor lasers subject to optical delayed feedback and optical injection. While the amount of the feedback/injection can be easily controlled, it is much more difficult to control the optical feedback/injection phase. We present extensive numerical investigations of the influence of the feedback/injection phases on laser-based reservoir computing systems with feedback. We show that a change in the phase can lead to a strong reduction in the reservoir computing system performance. We introduce a new readout layer design that -at least for some tasks- reduces this sensitivity to changes in the phase. It consists in optimizing the readout weights from a coherent combination of the reservoir's readout signal and its delayed version rather than only from the reservoir's readout signal as is usually done.

  16. 抗草甘膦杂草及其检测方法发展现状%Advances in research on glyphosate-resistant weeds and the detection methods

    Institute of Scientific and Technical Information of China (English)

    陈景超; 张朝贤; 黄红娟; 魏守辉

    2011-01-01

    Glyphosate-resistant weeds have evolved as a result of the intensive use of glyphosate for weed control in the world. The development of glyphosate and the occurrence and development of 21 glyphosate-resistant weeds reported all over the world were discussed. The development of the detection methods for the glyphosate-resistant weeds was described through the whole plant bioassay and biochemical assay. The knowledge contained in this review will provide basis for developing methods to detect the sensitivity of weeds to glyphosate and the systematic methods to monitor glyphosate-resistant weeds.%草甘膦在世界范围的多年大量使用已经引起了抗草甘膦杂草的产生.本文针对全球迄今为止发现的21种抗草甘膦杂草的发生、发展状况进行了论述.探讨了抗草甘膦杂草抗药性检测方法,分别从整株生物测定及生物化学等方面介绍了抗草甘膦杂草检测方法的研究现状,为抗草甘膦杂草检测方法的发展及其抗性监测方法的建立提供参考.

  17. Sensitive detection of rutin based on {beta}-cyclodextrin-chemically reduced graphene/Nafion composite film

    Energy Technology Data Exchange (ETDEWEB)

    Liu Kunping; Wei Jinping [School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000 (China); Wang Chunming, E-mail: wangcm@lzu.edu.cn [School of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000 (China)

    2011-05-30

    Highlights: > {beta}-CD-graphene composite obtained via a simple sonication-induced assembly. > Accelerating electron transfer on electrode to amplify the electrochemical signal. > A highly sensitive electrochemical sensor for rutin detection. > Good selectivity and reproducibility for the detection of rutin in real samples. - Abstract: An electrochemical sensor based on chemically reduced graphene (CRG) was developed for the sensitive detection of rutin. To construct the base of the sensor, a novel composite was initially fabricated and used as the substrate material by combining CRG and {beta}-cyclodextrin ({beta}-CD) via a simple sonication-induced assembly. Due to the high rutin-loading capacity on the electrode surface and the upstanding electric conductivity of graphene, the electrochemical response of the fabricated sensor was greatly enhanced and displayed excellent analytical performance for rutin detection from 6.0 x 10{sup -9} to 1.0 x 10{sup -5} mol L{sup -1} with a low detection limit of 2.0 x 10{sup -9} mol L{sup -1} at 3{sigma}. Moreover, the proposed electrochemical sensor also exhibited good selectivity and acceptable reproducibility and could be used for the detection of rutin in real samples. Therefore, the present work offers a new way to broaden the analytical applications of graphene in pharmaceutical analysis.

  18. 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

  19. Chronic hyperinsulinemia reduces insulin sensitivity and metabolic functions of brown adipocyte.

    Science.gov (United States)

    Rajan, Sujith; Shankar, Kripa; Beg, Muheeb; Varshney, Salil; Gupta, Abhishek; Srivastava, Ankita; Kumar, Durgesh; Mishra, Raj K; Hussain, Zakir; Gayen, Jiaur R; Gaikwad, Anil N

    2016-09-01

    The growing pandemics of diabetes have become a real threat to world economy. Hyperinsulinemia and insulin resistance are closely associated with the pathophysiology of type 2 diabetes. In pretext of brown adipocytes being considered as the therapeutic strategy for the treatment of obesity and insulin resistance, we have tried to understand the effect of hyperinsulinemia on brown adipocyte function. We here with for the first time report that hyperinsulinemia-induced insulin resistance in brown adipocyte is also accompanied with reduced insulin sensitivity and brown adipocyte characteristics. CI treatment decreased expression of brown adipocyte-specific markers (such as PRDM16, PGC1α, and UCP1) and mitochondrial content as well as activity. CI-treated brown adipocytes showed drastic decrease in oxygen consumption rate (OCR) and spare respiratory capacity. Morphological study indicates increased accumulation of lipid droplets in CI-treated brown adipocytes. We have further validated these findings in vivo in C57BL/6 mice implanted with mini-osmotic insulin pump for 8weeks. CI treatment in mice leads to increased body weight gain, fat mass and impaired glucose intolerance with reduced energy expenditure and insulin sensitivity. CI-treated mice showed decreased BAT characteristics and function. We also observed increased inflammation and ER stress markers in BAT of CI-treated animals. The above results conclude that hyperinsulinemia has deleterious effect on brown adipocyte function, making it susceptible to insulin resistance. Thus, the above findings have greater implication in designing approaches for the treatment of insulin resistance and diabetes via recruitment of brown adipocytes. PMID:27340034

  20. 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; Gerhard, Daniel;

    2015-01-01

    .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...

  1. Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate.

    Directory of Open Access Journals (Sweden)

    Cong Wang

    Full Text Available Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta. Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina regardless of DIP condition. Group V (Amphidinium carterae exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine

  2. Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate

    Science.gov (United States)

    Wang, Cong; Lin, Xin; Li, Ling; Lin, Senjie

    2016-01-01

    Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P) nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta). Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP) conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum) could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella) could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana) and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina) regardless of DIP condition. Group V (Amphidinium carterae) exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine phytoplankton

  3. Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate.

    Science.gov (United States)

    Wang, Cong; Lin, Xin; Li, Ling; Lin, Senjie

    2016-01-01

    Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P) nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta). Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP) conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum) could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella) could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana) and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina) regardless of DIP condition. Group V (Amphidinium carterae) exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine phytoplankton

  4. Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate.

    Science.gov (United States)

    Wang, Cong; Lin, Xin; Li, Ling; Lin, Senjie

    2016-01-01

    Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P) nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta). Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP) conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum) could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella) could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana) and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina) regardless of DIP condition. Group V (Amphidinium carterae) exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine phytoplankton

  5. 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.

  6. 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

    Directory of Open Access Journals (Sweden)

    M.S. Moreira

    2010-01-01

    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.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 effective 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

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

    Directory of Open Access Journals (Sweden)

    F.A. Petter

    2007-01-01

    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 conditions 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.

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

    DEFF Research Database (Denmark)

    Rasmussen, F; Mikkelsen, D; Hancox, R J;

    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 (CR...... inflammation in young adulthood may lead to impaired lung function independently of the effects of smoking, obesity, cardiorespiratory fitness, asthma and eosinophilic inflammation....... 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...

  9. 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)

  10. Effects of the glyphosate active ingredient and a formulation on Lemna gibba L. at different exposure levels and assessment end-points.

    Science.gov (United States)

    Sobrero, M C; Rimoldi, F; Ronco, A E

    2007-11-01

    The use of formulations of the herbicide glyphosate in transgenic crops of the Pampa's plains of Argentina has extensively increased, though there is scarce information of its impact on non-target vascular plants from agro-ecosystem related surface waters. The sensitivity of a local clone of the macrophyte Lemna gibba L. to glyphosate active principle and Roundup Max formulation was studied in standardized laboratory conditions. Phytotoxic effects, considering the aquatic route, at a concentration range of glyphosate between 0.5 and 80 mg L(-1) as active ingredient during 10 days of exposure were assessed on plant population growth, frond growth, shape and number, total chlorophyll content and colony architecture. Exposure to 1 mg L(-1) of glyphosate (an expected environmental concentration) affects all the studied assessment endpoints, except for population growth and chlorophyll content. Equivalent concentrations of this herbicide as the active ingredient or RoundupMax indicate higher phytotocity of the formulation. Exposed plants at concentrations of herbicide between 1 and 7.5 mg L(-1) exhibit after two days a recovery of the multiplication rate. Frond aggregation and longer stipe was detected between 1 and 15 mg L(-1) of glyphosate, determining more open colony architecture. At higher concentrations of the herbicide fronds break-up. Comparisons with literature data indicate a higher sensitivity of the L. gibba local clone with respect to L. minor and algal species, and also a similar response to the herbicide in field experiments with the same species. PMID:17940715

  11. 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)

  12. Characterization of glyphosate resistance in cloned Amaranthus palmeri plants

    Science.gov (United States)

    Glyphosate resistant Palmer amaranth from Georgia (GA) possesses multiple copies of the target site, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) of this herbicide. Cloned plants of glyphosate-resistant Palmer amaranth biotypes from Mississippi (MS) were compared with GA populations using le...

  13. Uses of glyphosate in German arable farming – operational aspects

    Directory of Open Access Journals (Sweden)

    Wiese, Armin

    2016-02-01

    Full Text Available Glyphosate is the most frequently used herbicide active ingredient in Germany. Studies regarding its usage in non-GMO arable farming are still rare even though it plays an important role in several agronomic situations. Therefore, we conducted a comprehensive survey, which was carried out among conventional German farms in Winter 2014/2015. Based on the results of this survey we analyzed via cluster analysis how types of farms differ in terms of glyphosate usage. An illustration of seven clusters allows deep insights into arable farm structures. The farm types can be distinguished regarding their tillage system and similar to this differentiation also concerning their intensity of glyphosate application. Furthermore, it becomes obvious that farm clusters with a higher level of glyphosate usage are characterized by a lower number of labourers per hectare, more arable land and/or enhanced cover cropping. Moreover, groups of farmers who rely more on glyphosate are more likely to state that they need glyphosate for herbicide resistance management. Farmers’ assessments of the economic importance of glyphosate usage vary depending on the type of farm. By means of the farm clusters, the most important situations of glyphosate usage can be further analyzed economically and scenarios for impact assessments can be made.

  14. Hormesis with glyphosate depends on coffee growth stage

    Science.gov (United States)

    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 ...

  15. Economic assessment of alternatives for glyphosate application in arable farming

    Directory of Open Access Journals (Sweden)

    Kehlenbeck, Hella

    2016-02-01

    Full Text Available Application and sales of herbicides with glyphosate have strongly increased in Germany during the past 10 years. This has raised a number of questions and discussions concerning glyphosate use. Therefore, this paper identifies and evaluates alternatives with an efficacy almost equivalent to glyphosate for different treatmentareas in terms of economic consequences for farms in comparison to glyphosate use by way of example. With the help of exemplary crop rotations uses in arable farming for winter wheat, winter oilseed rape, winter barley, maize and summer barley were analyzed. Within a “worst case scenario” a complete abandonment of glyphosate applications was assumed. Different tillage systems (plough, no-plough were considered. The only alternatives with an efficacy almost equivalent to glyphosate were mechanical measures. For the analyzed treatment-areas (desiccation, pre-sowing, stubble no approved and efficient chemical alternative could be identified. The economic advantages and disadvantages of substituting glyphosate by mechanical alternatives were strongly depending on the treatment-area, the efficacy concerning yield expectations (in comparison to glyphosate use, the tillage system, the necessity of grain drying as well as further operational factors such as the availability of sufficient field work days and mechanical equipment.

  16. Glyphosate applications on arable fields considerably coincide with migrating amphibians.

    Science.gov (United States)

    Berger, Gert; Graef, Frieder; Pfeffer, Holger

    2013-01-01

    Glyphosate usage is increasing worldwide and the application schemes of this herbicide are currently changing. Amphibians migrating through arable fields may be harmed by Glyphosate applied to field crops. We investigated the population-based temporal coincidence of four amphibian species with Glyphosate from 2006 to 2008. Depending on a) age- and species-specific main migration periods, b) crop species, c) Glyphosate application mode for crops, and d) the presumed DT50 value (12 days or 47 days) of Glyphosate, we calculated up to 100% coincidence with Glyphosate. The amphibians regularly co-occur with pre-sowing/pre-emerging Glyphosate applications to maize in spring and with stubble management prior to crop sowing in late summer and autumn. Siccation treatment in summer coincides only with early pond-leaving juveniles. We suggest in-depth investigations of both acute and long-term effects of Glyphosate applications on amphibian populations not only focussed on exposure during aquatic periods but also terrestrial life stages.

  17. Soil Depth and Tillage Effects on Glyphosate Degradation

    Science.gov (United States)

    The use of glyphosate-resistant crops facilitated the widespread adoption of no-tillage (NT) cropping systems. The experimental objectives were to determine glyphosate sorption, mineralization, and persistence at two depths [0- to 2- cm (A) and 2- to 10-cm (B)] in a silt loam managed under long ter...

  18. 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...

  19. 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 1.35 million metric tons will be used annually by 2017. With the advent of glyphosate tolerant (GT) cropping more than 10 years 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.

  20. Dissipation of glyphosate from grapevine soils in Sonora, Mexico

    Directory of Open Access Journals (Sweden)

    Norma J. Salazar López

    2016-10-01

    Full Text Available Grapevine is one of the important crops in Sonora, due to revenue generation from its export to foreign countries. Among the most widely used herbicides for this crop is glyphosate, which is considered moderately toxic and persistent. The present research evaluates the dissipation of glyphosate in grapevine planted soil at three depths (5, 30 and 60 cm. Sampling was carried out before glyphosate application, and 5, 10, 18, 27, and 65 days after. Glyphosate was extracted from soil samples using ammonium hydroxide. The derivate extracts were partitioned with dichloromethane and analyzed using gas chromatography with pulsed flame photometric detector (PFPD. The results showed that average glyphosate residues are significantly greater at 5 cm (0.09 mg kg-1 than the other depths (30 and 60 cm, having a difference of 0.078 mg kg-1 between them (P < 0.03. Glyphosate concentration time profiles were similar; it reached maximum soil concentration in a range of 10 to 18 days after application. The half-life of glyphosate in soil has an average of 39 days at all depths. Our data suggests that the release in soil of glyphosate applied to weeds delays its transference to soil by 14 days, and extends residue half life to 55 days after application. These results could be the basis for further research, including more environmental parameters that could affect the dissipation or degradation process in soil.

  1. Reduced mtDNA copy number increases the sensitivity of tumor cells to chemotherapeutic drugs.

    Science.gov (United States)

    Mei, H; Sun, S; Bai, Y; Chen, Y; Chai, R; Li, H

    2015-04-02

    Many cancer drugs are toxic to cells by activating apoptotic pathways. Previous studies have shown that mitochondria have key roles in apoptosis in mammalian cells, but the role of mitochondrial DNA (mtDNA) copy number variation in the pathogenesis of tumor cell apoptosis remains largely unknown. We used the HEp-2, HNE2, and A549 tumor cell lines to explore the relationship between mtDNA copy number variation and cell apoptosis. We first induced apoptosis in three tumor cell lines and one normal adult human skin fibroblast cell line (HSF) with cisplatin (DDP) or doxorubicin (DOX) treatment and found that the mtDNA copy number significantly increased in apoptotic tumor cells, but not in HSF cells. We then downregulated the mtDNA copy number by transfection with shRNA-TFAM plasmids or treatment with ethidium bromide and found that the sensitivity of tumor cells to DDP or DOX was significantly increased. Furthermore, we observed that levels of reactive oxygen species (ROS) increased significantly in tumor cells with lower mtDNA copy numbers, and this might be related to a low level of antioxidant gene expression. Finally, we rescued the increase of ROS in tumor cells with lipoic acid or N-acetyl-L-cysteine and found that the apoptosis rate decreased. Our studies suggest that the increase of mtDNA copy number is a self-protective mechanism of tumor cells to prevent apoptosis and that reduced mtDNA copy number increases ROS levels in tumor cells, increases the tumor cells' sensitivity to chemotherapeutic drugs, and increases the rate of apoptosis. This research provides evidence that mtDNA copy number variation might be a promising new therapeutic target for the clinical treatment of tumors.

  2. Concerns over use of glyphosate-based herbicides and risks associated with exposures: a consensus statement.

    Science.gov (United States)

    Myers, John Peterson; Antoniou, Michael N; Blumberg, Bruce; Carroll, Lynn; Colborn, Theo; Everett, Lorne G; Hansen, Michael; Landrigan, Philip J; Lanphear, Bruce P; Mesnage, Robin; Vandenberg, Laura N; Vom Saal, Frederick S; Welshons, Wade V; Benbrook, Charles M

    2016-01-01

    The broad-spectrum herbicide glyphosate (common trade name "Roundup") was first sold to farmers in 1974. Since the late 1970s, the volume of glyphosate-based herbicides (GBHs) applied has increased approximately 100-fold. Further increases in the volume applied are likely due to more and higher rates of application in response to the widespread emergence of glyphosate-resistant weeds and new, pre-harvest, dessicant use patterns. GBHs were developed to replace or reduce reliance on herbicides causing well-documented problems associated with drift and crop damage, slipping efficacy, and human health risks. Initial industry toxicity testing suggested that GBHs posed relatively low risks to non-target species, including mammals, leading regulatory authorities worldwide to set high acceptable exposure limits. To accommodate changes in GBH use patterns associated with genetically engineered, herbicide-tolerant crops, regulators have dramatically increased tolerance levels in maize, oilseed (soybeans and canola), and alfalfa crops and related livestock feeds. Animal and epidemiology studies published in the last decade, however, point to the need for a fresh look at glyphosate toxicity. Furthermore, the World Health Organization's International Agency for Research on Cancer recently concluded that glyphosate is "probably carcinogenic to humans." In response to changing GBH use patterns and advances in scientific understanding of their potential hazards, we have produced a Statement of Concern drawing on emerging science relevant to the safety of GBHs. Our Statement of Concern considers current published literature describing GBH uses, mechanisms of action, toxicity in laboratory animals, and epidemiological studies. It also examines the derivation of current human safety standards. We conclude that: (1) GBHs are the most heavily applied herbicide in the world and usage continues to rise; (2) Worldwide, GBHs often contaminate drinking water sources, precipitation, and air

  3. Study of glyphosate transport through suspended particulate matter

    Science.gov (United States)

    Amiot, Audrey; Landry, David; Jadas-Hécart, Alain; La Jeunesse, Isabelle; Sourice, Stéphane; Ballouche, Aziz

    2014-05-01

    The results have been produced in a project aiming to improve the water quality of the Layon localy supported by stakeholders involved in the implementation of the Water Framework Directive as the SAGE-Layon Aubance. The study site is a small vineyard catchment (2.2 ha) of the Loire Valley. The slopes of the study site are between 8 and 40% resulting in strong erosive episodes during rainy event. The main objective is to understand the transfer of pesticide residues to stream. Preliminary results have shown glyphosate can be found with high concentrations during runoff. However this study was realized only in the dissolved phase. The objective is now to understand the glyphosate transport driven by SPM. The methodology developed has been (i) characterization and production of the erodible water fraction from soils aggregates; (ii) achievement of the adsorption of glyphosate on these erodible materials to compare this results with adsorption on soil sieved to 2 mm, (iii) achievement of the desorption of glyphosate on these erodible materials. Measurements have been performed on soil samples distinguishing weed or grassed soils. Soils are sieved to 2 mm or between 2 and 5 mm (to produce the erodible water fraction). Both fractions are then used to glyphosate sorption and desorption. The erodible fraction was produce with a wet sieving machine (eijkelkampt Method Kemper and Rosenau, 1986), using sieve porosity of 250 microns. The fraction obtained at 250 microns is considered to be the erodible water fraction and is used to study the adsorption and desorption of glyphosate. Kinetics has been first carried out then the isotherm to obtain the value of Kd. A ratio soil/solution of 1/5 was used. Successive desorption's method was chosen with a stirring time of 20 min, centrifugation at 6000 g and the supernatant in each desorption of 20 min is analyzed. This step is repeated 25 times. The main results of the study are: (i) adsorption of glyphosate is rapid and almost

  4. Assessing the Value of Glyphosate in the South African Agricultural Sector

    OpenAIRE

    Gouse, Marnus

    2014-01-01

    This study assessed the value of glyphosate in the South African agricultural sector with focus on the 2012/13 agricultural season. Glyphosate is the most used herbicide in South African and in 2012 more than 23 million litres of glyphosate was sold at an estimated value of R641 million. Glyphosate is a highly effective broad spectrum herbicide and the only herbicide on the market with a systemic mode of action. Glyphosate is considered to be, based on numerous scientific studies environmenta...

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

    OpenAIRE

    Alexa, Ersilia; 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...

  6. Rhizosphere processes as determinants for glyphosate damage of non-target plants

    OpenAIRE

    Bott, Sebastian

    2010-01-01

    Due to low production costs and high herbicidal efficiency, glyphosate is the most widely used wide-spectrum herbicide. Glyphosate acts as a non-selective, total herbicide by inhibiting the biosynthesis of aromatic amino acids. Apart from glyphosate drift contamination, risks of glyphosate toxicity to crop plants and other non-target organisms are generally considered as marginal, because glyphosate is almost instantaneously inactivated by adsorption to the soil matrix and rapid microbial/che...

  7. Effect of different doses of glyphosate in soybean

    Directory of Open Access Journals (Sweden)

    S. A. Gomes

    2013-07-01

    Full Text Available Abstract: Brazil ranks second in production of conventional soybeans and third in production of transgenic soybeans. The main advantage of transgenic soybean is resistant to the herbicide glyphosate, but the continued use of exaggeration and even of the same herbicide on soybean can significantly decrease acquired resistance. This work aimed to evaluate the effects of different doses of glyphosate can result in soybean. The experiment was conducted in a greenhouse on the Campus of UFMT in Sinop-MT, and evaluated five doses of glyphosate in transgenic soybeans intercropped with two conventional soybeans. The characters were evaluated for phytotoxicity scores and length of the root system. It was found that, regardless of the amount of glyphosate applied occur symptoms of phytotoxicity in conventional and transgenic soybean. Whereas the most damage will be in conventional soybean, and transgenic soybean little affected by the action of the herbicide.Key words: Glycine max, glyphosate, phytotoxicity

  8. Identification of Glyphosate Resistance in Lolium rigidum Gaudin

    Directory of Open Access Journals (Sweden)

    Danijela Pavlović

    2011-01-01

    Full Text Available Glyphosate resistance was found in Lolium rigidum Gaudin (Rigid ryegrass, LOLRI inSouth Africa. Suspected glyphosate-resistant L. rigidum populations were collected andgrown under greenhouse conditions. The plants were sprayed with a range of doses of glyphosate35 days after planting and shoot dry biomass was determined 17 days after herbicidetreatment. Based on the dose-response experiment conducted in the greenhouse,one population of L. rigidum suspected to be resistant to glyphosate was approximately 5.3fold more resistant than susceptible population. The other population was 2.8 fold moreresistant than susceptible population. Difference between the two suspected resistant populationswas 1.9 fold. All plants were treated with glyphosate (1000 g a.i. ha-1 and shikimicacid was extracted 2, 4 and 6 days after treatment. The plants of susceptible populationsaccumulated more shikimic acid than other two populations.

  9. 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)

  10. Reduced Cortical Thickness as an Outcome of Differential Sensitivity to Environmental Risks in Schizophrenia

    NARCIS (Netherlands)

    Habets, Petra; Marcelis, Machteld; Gronenschild, Ed; Drukker, Marian; van Os, Jim

    2011-01-01

    Background: The etiology of schizophrenia is thought to involve differential likely genetically mediated sensitivity to environmental exposures. However, examination of differential sensitivity in models of psychopathologic constructs is subject to bias because psychopathology itself may distort exp

  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

  12. Changes in rhizosphere bacterial gene expression following glyphosate treatment.

    Science.gov (United States)

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

    2016-05-15

    In commercial agriculture, populations and interactions of rhizosphere microflora are potentially affected by the use of specific agrichemicals, possibly by affecting gene expression in these organisms. To investigate this, we examined changes in bacterial gene expression within the rhizosphere of glyphosate-tolerant corn (Zea mays) and soybean (Glycine max) in response to long-term glyphosate (PowerMAX™, Monsanto Company, MO, USA) treatment. A long-term glyphosate application study was carried out using rhizoboxes under greenhouse conditions with soil previously having no history of glyphosate exposure. Rhizosphere soil was collected from the rhizoboxes after four growing periods. Soil microbial community composition was analyzed using microbial phospholipid fatty acid (PLFA) analysis. Total RNA was extracted from rhizosphere soil, and samples were analyzed using RNA-Seq analysis. A total of 20-28 million bacterial sequences were obtained for each sample. Transcript abundance was compared between control and glyphosate-treated samples using edgeR. Overall rhizosphere bacterial metatranscriptomes were dominated by transcripts related to RNA and carbohydrate metabolism. We identified 67 differentially expressed bacterial transcripts from the rhizosphere. Transcripts downregulated following glyphosate treatment involved carbohydrate and amino acid metabolism, and upregulated transcripts involved protein metabolism and respiration. Additionally, bacterial transcripts involving nutrients, including iron, nitrogen, phosphorus, and potassium, were also affected by long-term glyphosate application. Overall, most bacterial and all fungal PLFA biomarkers decreased after glyphosate treatment compared to the control. These results demonstrate that long-term glyphosate use can affect rhizosphere bacterial activities and potentially shift bacterial community composition favoring more glyphosate-tolerant bacteria. PMID:26901800

  13. Changes in rhizosphere bacterial gene expression following glyphosate treatment.

    Science.gov (United States)

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

    2016-05-15

    In commercial agriculture, populations and interactions of rhizosphere microflora are potentially affected by the use of specific agrichemicals, possibly by affecting gene expression in these organisms. To investigate this, we examined changes in bacterial gene expression within the rhizosphere of glyphosate-tolerant corn (Zea mays) and soybean (Glycine max) in response to long-term glyphosate (PowerMAX™, Monsanto Company, MO, USA) treatment. A long-term glyphosate application study was carried out using rhizoboxes under greenhouse conditions with soil previously having no history of glyphosate exposure. Rhizosphere soil was collected from the rhizoboxes after four growing periods. Soil microbial community composition was analyzed using microbial phospholipid fatty acid (PLFA) analysis. Total RNA was extracted from rhizosphere soil, and samples were analyzed using RNA-Seq analysis. A total of 20-28 million bacterial sequences were obtained for each sample. Transcript abundance was compared between control and glyphosate-treated samples using edgeR. Overall rhizosphere bacterial metatranscriptomes were dominated by transcripts related to RNA and carbohydrate metabolism. We identified 67 differentially expressed bacterial transcripts from the rhizosphere. Transcripts downregulated following glyphosate treatment involved carbohydrate and amino acid metabolism, and upregulated transcripts involved protein metabolism and respiration. Additionally, bacterial transcripts involving nutrients, including iron, nitrogen, phosphorus, and potassium, were also affected by long-term glyphosate application. Overall, most bacterial and all fungal PLFA biomarkers decreased after glyphosate treatment compared to the control. These results demonstrate that long-term glyphosate use can affect rhizosphere bacterial activities and potentially shift bacterial community composition favoring more glyphosate-tolerant bacteria.

  14. Enhanced sensitivity in H photofragment detection by two-color reduced-Doppler ion imaging

    Science.gov (United States)

    Epshtein, Michael; Portnov, Alexander; Kupfer, Rotem; Rosenwaks, Salman; Bar, Ilana

    2013-11-01

    Two-color reduced-Doppler (TCRD) and one-color velocity map imaging (VMI) were used for probing H atom photofragments resulting from the ˜243.1 nm photodissociation of pyrrole. The velocity components of the H photofragments were probed by employing two counterpropagating beams at close and fixed wavelengths of 243.15 and 243.12 nm in TCRD and a single beam at ˜243.1 nm, scanned across the Doppler profile in VMI. The TCRD imaging enabled probing of the entire velocity distribution in a single pulse, resulting in enhanced ionization efficiency, as well as improved sensitivity and signal-to-noise ratio. These advantages were utilized for studying the pyrrole photodissociation at ˜243.1 and 225 nm, where the latter wavelength provided only a slight increase in the H yield over the self-signal from the probe beams. The TCRD imaging enabled obtaining high quality H+ images, even for the low H photofragment yields formed in the 225 nm photolysis process, and allowed determining the velocity distributions and anisotropy parameters and getting insight into pyrrole photodissociation.

  15. Enhanced sensitivity in H photofragment detection by two-color reduced-Doppler ion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Epshtein, Michael; Portnov, Alexander; Kupfer, Rotem; Rosenwaks, Salman; Bar, Ilana, E-mail: ibar@bgu.ac.il [Department of Physics, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)

    2013-11-14

    Two-color reduced-Doppler (TCRD) and one-color velocity map imaging (VMI) were used for probing H atom photofragments resulting from the ∼243.1 nm photodissociation of pyrrole. The velocity components of the H photofragments were probed by employing two counterpropagating beams at close and fixed wavelengths of 243.15 and 243.12 nm in TCRD and a single beam at ∼243.1 nm, scanned across the Doppler profile in VMI. The TCRD imaging enabled probing of the entire velocity distribution in a single pulse, resulting in enhanced ionization efficiency, as well as improved sensitivity and signal-to-noise ratio. These advantages were utilized for studying the pyrrole photodissociation at ∼243.1 and 225 nm, where the latter wavelength provided only a slight increase in the H yield over the self-signal from the probe beams. The TCRD imaging enabled obtaining high quality H{sup +} images, even for the low H photofragment yields formed in the 225 nm photolysis process, and allowed determining the velocity distributions and anisotropy parameters and getting insight into pyrrole photodissociation.

  16. 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.

  17. Side-Effects of Glyphosate to the Parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae).

    Science.gov (United States)

    Stecca, C S; Bueno, A F; Pasini, A; Silva, D M; Andrade, K; Filho, D M Z

    2016-04-01

    The aim of this study was to compare the side-effects of glyphosate to the parasitoid Telenomus remus Nixon (Hymenoptera: Platygastridae) when parasitoids were exposed to this chemical at the pupal (inside host eggs) and adult stages. Bioassays were conducted under laboratory conditions according to the International Organization for Biological Control (IOBC) standard methods for testing side-effects of pesticides to egg parasitoids. Different glyphosate-based pesticides (Roundup Original®, Roundup Ready®, Roundup Transorb®, Roundup WG®, and Zapp Qi®) were tested at the same acid equivalent concentration. Treatments were classified following the IOBC toxicity categories as (1) harmless, (2) slightly harmful, (3) moderately harmful, and (4) harmful. When tested against T. remus adults, Roundup Original®, Roundup Ready®, Roundup Transorb®, and Roundup WG® reduced parasitism 2 days after parasitoid emergence, being classified as slightly harmful. Differently, when tested against T. remus pupae, all tested glyphosate-based products did not differ in their lethal effect and therefore did not reduce T. remus adult emergence or parasitism capacity, being classified as harmless. However, differences on sublethal toxicity were found. Parasitism of individuals emerging from parasitized eggs sprayed at the pupal stage of T. remus with Zapp Qi® was lower compared to control, but parasitism was still higher than 66%, and therefore, Zapp Qi® was still classified as harmless. In conclusion, all tested glyphosate-based products can be used in agriculture without negative impact to T. remus as none was classified as harmful or moderately harmful to this parasitoid when exposure occurred at the pupal or adult stages. PMID:26842914

  18. Low doses of glyphosate change the response of soybean to later glyphosate exposures

    Science.gov (United States)

    The stimulatory effect of low doses of toxic substances is known as hormesis. Many herbicides that cause severe injury to plants at recommended rates, promote growth or have other stimulatory effects at very low doses. The objective of this study was to evaluate glyphosate-induced hormesis in soyb...

  19. 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

  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

    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

  1. 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.

  2. The EPSPS Pro106Ser substitution solely accounts for glyphosate resistance in a goosegrass (Eleusine indica) population from Tennessee, United States

    Institute of Scientific and Technical Information of China (English)

    Janel L Huffman; Chance W Riggins; Lawrence E Steckel; Patrick J Tranel

    2016-01-01

    Previous studies have documented the occurrence of glyphosate-resistant (GR) goosegrass (Eleusine indica (L.) Gaertn.) and, in at least some cases, resistance is due to an altered target site. Research was performed to determine if an altered target site was responsible for GR in a Tennessee, United States goosegrass population (TennGR). DNA sequencing revealed a mutation in TennGR plants conferring the Pro106Ser 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) substitution previously identiifed in other GR populations. F2 populations were derived from TennGR plants crossed with plants from a glyphosate-susceptible population (TennGS) and analyzed for their response to glyphosate and genotyped at the EPSPS locus. Plants from the F2 populations segregated 1:2:1 sensitive:intermediate:resistant in response to a selec-tive dose of glyphosate, and these responses co-segregated with the EPSPS genotypes (PP106, PS106, and SS106). To separately investigate the effect of the Pro106Ser substitution on GR, glyphosate dose-response curves and 50% effective dose (ED50) values were compared among the three genotypes and the two parental populations. The SS106 genotype was 3.4-fold resistant relative to the PP106 genotype, identical to the resistance level obtained when comparing the resistant and susceptible parental populations. We conclude that the mutation conferring a Pro106Ser EPSPS mutation is solely responsible for GR in the TennGR goosegrass population.

  3. 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, William A; Rice, Karen C; Focazio, Michael J; Salmons, Sue; Barry, Robert X

    2009-08-01

    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 (microg/l) in samples from Rands Ditch and Browns Ditch in DeSoto National Wildlife Refuge. Glyphosate was measured at the highest concentration (328 microg/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 microg/l. Aminomethylphosphonic acid, triclopyr, and nicosulfuron also were detected at concentrations greater than 3.0 microg/l. PMID:18677547

  4. 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

  5. Multiple resistance to glyphosate and pyrithiobac in Palmer amaranth (Amaranthus palmeri) from Mississippi and response to flumiclorac

    Science.gov (United States)

    Greenhouse and laboratory studies were conducted to confirm and quantify glyphosate resistance, to investigate interactions between flumiclorac and glyphosate mixtures on weed control, to determine patterns of absorption and translocation of glyphosate applied alone and in combination with flumiclor...

  6. Potential Accumulative Effect of the Herbicide Glyphosate on Glyphosate-Tolerant Maize Rhizobacterial Communities over a Three-Year Cultivation Period

    OpenAIRE

    Jorge Barriuso; Silvia Marín; Mellado, Rafael P.

    2011-01-01

    BACKGROUND: Glyphosate is a herbicide that is liable to be used in the extensive cultivation of glyphosate-tolerant cultivars. The potential accumulation of the relative effect of glyphosate on the rhizobacterial communities of glyphosate-tolerant maize has been monitored over a period of three years. METHODOLOGY/PRINCIPAL FINDINGS: The composition of rhizobacterial communities is known to vary with soil texture, hence, the analyses have been performed in two agricultural fields with a differ...

  7. 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; Ørsted, Michael

    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...... 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...

  8. 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.

  9. What have the mechanisms of resistance to glyphosate taught us?

    Science.gov (United States)

    Shaner, Dale L; Lindenmeyer, Richard Bradley; Ostlie, Michael H

    2012-01-01

    The intensive use of glyphosate alone to manage weeds has selected populations that are glyphosate resistant. The three mechanisms of glyphosate resistance that have been elucidated are (1) target-site mutations, (2) gene amplification and (3) altered translocation due to sequestration. What have we learned from the selection of these mechanisms, and how can we apply those lessons to future herbicide-resistant crops and new mechanisms of action? First, the diversity of glyphosate resistance mechanisms has helped further our understanding of the mechanism of action of glyphosate and advanced our knowledge of plant physiology. Second, the relatively rapid evolution of glyphosate-resistant weed populations provides further evidence that no herbicide is invulnerable to resistance. Third, as new herbicide-resistant crops are developed and new mechanisms of action are discovered, the weed science community needs to ensure that we apply the lessons we have learned on resistance management from the experience with glyphosate. Every new weed management system must be evaluated during development for its potential to select for resistance, and stewardship programs should be in place when the new program is introduced.

  10. Glyphosate in Runoff Waters and in the Root-Zone: A Review

    Directory of Open Access Journals (Sweden)

    Lyndsay E. Saunders

    2015-11-01

    Full Text Available Glyphosate is the most commonly-used herbicide in the world. The present review summarizes the discovery, prevalence, chemical and physical properties, mode of action and effects in plants, glyphosate resistance and the environmental fate of glyphosate. Numerous studies are reviewed that demonstrate that glyphosate may run off of fields where it is applied, while other studies provide evidence that plant roots can take up glyphosate. Non-target vegetation may be exposed to glyphosate in the root-zone, where it has the potential to remove aqueous glyphosate from the system. Further study on the effects of root-zone glyphosate on non-target vegetation is required to develop best management practices for land managers seeking to ameliorate the effects of root-zone glyphosate exposure.

  11. 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

  12. Glyphosate Control of Orange and Brown Rusts in Glyphosate-Sensitive Sugarcane Cultivars

    Science.gov (United States)

    Technical Abstract: Brown and orange rust diseases cause substantial yield reductions on sugarcane (Saccharum spp.) in Florida and other regions where sugarcane is grown. Brown rust caused by Puccinia melanocephala Syd. & P. Syd has been present in Florida since 1978 and orange rust caused by Pucci...

  13. 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...

  14. 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

  15. Glyphosate on digestive enzymes activity in piava (Leporinus obtusidens

    Directory of Open Access Journals (Sweden)

    Joseânia Salbego

    2014-09-01

    Full Text Available The effects of glyphosate, a nonselective herbicide (1.0 or 5.0mg L-1 on digestive enzymes activity (stomach and intestine were evaluated in juveniles of piava (Leporinus obtusidens after 90 days of exposure. The activity of acid protease, trypsin, chymotrypsin and amylase increased with the increase of glyphosate concentration. These results indicate that glyphosate affects digestive enzyme activities in this species, and may be an indicator of poor nutrient availability when fish survive in herbicide-contaminated water.

  16. Characterization of Halomonas Varabilis Strain HTG7 Conferring Glyphosate Resistance

    Institute of Scientific and Technical Information of China (English)

    Liu Zhu(刘柱); Liang Aimin; Ping Shuzhen; Zhang Wei; Chen Ming; Yang Zhirong; Lin Min

    2004-01-01

    Bcterial strain HTG7 is isolated from extremely glyphosate-polluted soil. It is identified as Halomonas Varabilis. It can tolerate in 500 m mol/L glyphosate concentration. Physiological characterization of strain HTG7 shows that the optimum pH and temperature are 7.0 and 30℃, respectively. It grows well in the NaCl concentrations ranging from 0% to 10%. A plasmid pACYC184 carrying a 3.5 kb DNA fragment, which confers increased glyphosate tolerance, is cloned. The DNA fragment is able to complement with an E.coli auxotrophic aroA mutant.

  17. 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.

  18. 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

    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.

  19. α-Lipoic Acid Reduces Hypertension and Increases Baroreflex Sensitivity in Renovascular Hypertensive Rats

    OpenAIRE

    Queiroz, Thyago; Guimarães, Drielle; Mendes-Junior, Leônidas; Braga, Valdir

    2012-01-01

    Renovascular hypertension has robust effects on control of blood pressure, including an impairment in baroreflex mechanisms, which involves oxidative stress. Although α-lipoic acid (LA) has been described as a potent antioxidant, its effect on renovascular hypertension and baroreflex sensitivity (BRS) has not been investigated. In the present study we analyzed the effects caused by chronic treatment with LA on blood pressure, heart rate and baroreflex sensitivity (sympathetic and parasympathe...

  20. Reduced thermal sensitivity and Nav1.8 and TRPV1 channel expression in sensory neurons of aged mice

    OpenAIRE

    Wang, Shuying; Davis, Brian M.; Zwick, Melissa; Waxman, Stephen G.; Albers, Kathryn M.

    2005-01-01

    Sensory neurons in aging mammals undergo changes in anatomy, physiology and gene expression that correlate with reduced sensory perception. In this study we compared young and aged mice to identify proteins that might contribute to this loss of sensation. We first show using behavioral testing that thermal sensitivity in aged male and female mice is reduced. Expression of sodium channel (Nav1.8 and Nav1.9) and transient receptor potential vanilloid (TRPV) channels in DRG and peripheral nerves...

  1. High mobility group A1 protein expression reduces the sensitivity of colon and thyroid cancer cells to antineoplastic drugs

    OpenAIRE

    D’Angelo, Daniela; Mussnich, Paula; De Rosa, Roberta; Bianco, Roberto; Tortora, Giampaolo; Fusco, Alfredo

    2014-01-01

    Background Development of resistance to conventional drugs and novel biological agents often impair long-term chemotherapy. HMGA gene overexpression is often associated with antineoplastic drug resistance and reduced survival. Inhibition of HMGA expression in thyroid cancer cells reduces levels of ATM protein, the main cellular sensor of DNA damage, and enhances cellular sensitivity to DNA-damaging agents. HMGA1 overexpression promotes chemoresistance to gemcitabine in pancreatic adenocarcino...

  2. Photosynthetic activity of coffee after application of glyphosate subdoses - doi: 10.4025/actasciagron.v35i1.15440

    Directory of Open Access Journals (Sweden)

    Felipe Paolinelli de Carvalho

    2012-08-01

    Full Text Available 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.

  3. Intercropping frost-sensitive legume crops with winter oilseed rape reduces weed competition, insect damage, and improves nitrogen use efficiency

    OpenAIRE

    Cadoux Stéphane; Sauzet Gilles; Valantin-Morison Muriel; Pontet Célia; Champolivier Luc; Robert Céline; Lieven Jean; Flénet Francis; Mangenot Olivier; Fauvin Pascal; Landé Nathalie

    2015-01-01

    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 ...

  4. Regional differences in time to pregnancy among fertile women from five Colombian regions with different use of glyphosate.

    Science.gov (United States)

    Sanin, Luz-Helena; Carrasquilla, Gabriel; Solomon, Keith R; Cole, Donald C; Marshall, E J P

    2009-01-01

    The objective of this study was to test whether there was an association between the use of glyphosate when applied by aerial spray for the eradication of illicit crops (cocaine and poppy) and time to pregnancy (TTP) among fertile women. A retrospective cohort study (with an ecological exposure index) of first pregnancies was undertaken in 2592 fertile Colombian women from 5 regions with different uses of glyphosate. Women were interviewed regarding potential reproductive, lifestyle, and work history predictors of TTP, which was measured in months. Fecundability odds ratios (fOR) were estimated using a discrete time analogue of Cox's proportional hazard model. There were differences in TTP between regions. In the final multivariate model, the main predictor was the region adjusted by irregular relationship with partner, maternal age at first pregnancy, and, marginally, coffee consumption and self-perception of water pollution. Boyaca, a region with traditional crops and. recently, illicit crops without glyphosate eradication spraying (manual eradication), displayed minimal risk and was the reference region. Other regions, including Sierra Nevada (control area, organic agriculture), Putumayo and Narino (illicit crops and intensive eradication spray program), and Valle del Cauca, demonstrated greater risk of longer TTP, with the highest risk for Valle del Cauca (fOR 0.15, 95% CI 0.12, 0.18), a sugar-cane region with a history of use of glyphosate and others chemicals for more than 30 yr. The reduced fecundability in some regions was not associated with the use of glyphosate for eradication spraying. The observed ecological differences remain unexplained and may be produced by varying exposures to environmental factors, history of contraceptive programs in the region, or psychological distress. Future studies examining these or other possible causes are needed. PMID:19672763

  5. Evolved glyphosate-resistant weeds around the world: lessons to be learnt.

    Science.gov (United States)

    Powles, Stephen B

    2008-04-01

    Glyphosate is the world's most important herbicide, with many uses that deliver effective and sustained control of a wide spectrum of unwanted (weedy) plant species. Until recently there were relatively few reports of weedy plant species evolving resistance to glyphosate. Since 1996, the advent and subsequent high adoption of transgenic glyphosate-resistant crops in the Americas has meant unprecedented and often exclusive use of glyphosate for weed control over very large areas. Consequently, in regions of the USA where transgenic glyphosate-resistant crops dominate, there are now evolved glyphosate-resistant populations of the economically damaging weed species Ambrosia artemissifolia L., Ambrosia trifida L., Amaranthus palmeri S Watson, Amaranthus rudis JD Sauer, Amaranthus tuberculatus (Moq) JD Sauer and various Conyza and Lolium spp. Likewise, in areas of transgenic glyphosate-resistant crops in Argentina and Brazil, there are now evolved glyphosate-resistant populations of Sorghum halepense (L.) Pers and Euphorbia heterophylla L. respectively. As transgenic glyphosate-resistant crops will remain very popular with producers, it is anticipated that glyphosate-resistant biotypes of other prominent weed species will evolve over the next few years. Therefore, evolved glyphosate-resistant weeds are a major risk for the continued success of glyphosate and transgenic glyphosate-resistant crops. However, glyphosate-resistant weeds are not yet a problem in many parts of the world, and lessons can be learnt and actions taken to achieve glyphosate sustainability. A major lesson is that maintenance of diversity in weed management systems is crucial for glyphosate to be sustainable. Glyphosate is essential for present and future world food production, and action to secure its sustainability for future generations is a global imperative.

  6. Glyphosate-resistant weeds of South American cropping systems: an overview.

    Science.gov (United States)

    Vila-Aiub, Martin M; Vidal, Ribas A; Balbi, Maria C; Gundel, Pedro E; Trucco, Frederico; Ghersa, Claudio M

    2008-04-01

    Herbicide resistance is an evolutionary event resulting from intense herbicide selection over genetically diverse weed populations. In South America, orchard, cereal and legume cropping systems show a strong dependence on glyphosate to control weeds. The goal of this report is to review the current knowledge on cases of evolved glyphosate-resistant weeds in South American agriculture. The first reports of glyphosate resistance include populations of highly diverse taxa (Lolium multiflorum Lam., Conyza bonariensis L., C. canadensis L.). In all instances, resistance evolution followed intense glyphosate use in fruit fields of Chile and Brazil. In fruit orchards from Colombia, Parthenium hysterophorus L. has shown the ability to withstand high glyphosate rates. The recent appearance of glyphosate-resistant Sorghum halepense L. and Euphorbia heterophylla L. in glyphosate-resistant soybean fields of Argentina and Brazil, respectively, is of major concern. The evolution of glyphosate resistance has clearly taken place in those agroecosystems where glyphosate exerts a strong and continuous selection pressure on weeds. The massive adoption of no-till practices together with the utilization of glyphosate-resistant soybean crops are factors encouraging increase in glyphosate use. This phenomenon has been more evident in Argentina and Brazil. The exclusive reliance on glyphosate as the main tool for weed management results in agroecosystems biologically more prone to glyphosate resistance evolution.

  7. 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.

  8. Uses of glyphosate in German arable farming – operational aspects

    OpenAIRE

    Wiese, Armin; Schulte, Michael; Theuvsen, Ludwig; Steinmann, Horst-Henning

    2016-01-01

    Glyphosate is the most frequently used herbicide active ingredient in Germany. Studies regarding its usage in non-GMO arable farming are still rare even though it plays an important role in several agronomic situations. Therefore, we conducted a comprehensive survey, which was carried out among conventional German farms in Winter 2014/2015. Based on the results of this survey we analyzed via cluster analysis how types of farms differ in terms of glyphosate usage. An illustration of seven clus...

  9. MON 79351 – a novel liquid glyphosate herbicide

    OpenAIRE

    Kiepe, Björn; Ophoff, Holger; Voegler, Wolfgang

    2012-01-01

    MON 79351 is a novel liquid glyphosate herbicide which represents the improved product generation within the Roundup® product family. Containing 480 g/l active ingredient, this liquid formulation exceeds our current distributed soluble concentrates in Germany. MON 79351 is formulated as a potassium salt and offers product advantages in contrast to conventional glyphosate products. In product development trials, MON 79351 provides an excellent efficacy against mono- and dicotyledonous annual a...

  10. 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

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

    DEFF Research Database (Denmark)

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

    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 cirrh...

  12. Strategies for reducing potentially avoidable hospitalizations for ambulatory care-sensitive conditions

    NARCIS (Netherlands)

    Freund, T.; Campbell, S.M.; Geissler, S.; Kunz, C.U.; Mahler, C.; Peters-Klimm, F.; Szecsenyi, J.

    2013-01-01

    PURPOSE: Hospitalizations for ambulatory care-sensitive conditions (ACSCs) are seen as potentially avoidable with optimal primary care. Little is known, however, about how primary care physicians rate these hospitalizations and whether and how they could be avoided. This study explores the complex c

  13. Children with a History of SLI Show Reduced Sensitivity to Audiovisual Temporal Asynchrony: An ERP Study

    Science.gov (United States)

    Kaganovich, Natalya; Schumaker, Jennifer; Leonard, Laurence B.; Gustafson, Dana; Macias, Danielle

    2014-01-01

    Purpose: The authors examined whether school-age children with a history of specific language impairment (H-SLI), their peers with typical development (TD), and adults differ in sensitivity to audiovisual temporal asynchrony and whether such difference stems from the sensory encoding of audiovisual information. Method: Fifteen H-SLI children, 15…

  14. Characterization of a new highly sensitive immunometric assay for thyroglobulin with reduced interference from autoantibodies.

    Science.gov (United States)

    Broughton, Marianne Nordlund; Nome, Ragnhild; Sandven, Ingvill; Paus, Elisabeth; Bjøro, Trine

    2016-06-01

    Measurements of serum thyroglobulin (Tg) with sensitive immunoassays are of great importance for the management of patients with differentiated thyroid carcinomas. However, interference of circulating autoantibodies to Tg (hTgAb) hampers the usefulness of most assays. We have produced a panel of monoclonal antibodies (mAbs) selected to bind Tg in the presence of Tg autoantibodies and developed a sensitive immunoassay for Tg with minor interference by hTgAbs. The antibodies were characterized by cross-inhibition and immunoassay combination studies, as well as affinity estimation. The within-run and total imprecision of the assay were determined with 2664 samples in 60 separate runs. The most sensitive assay combination with superior protection against autoantibodies consisted of two solid phase mAbs and two tracer mAbs with distinct binding sites. The assay was linear and displayed a wide dynamic range up to 1342 μg/l with a functional sensitivity of 0.1 μg/l and a total imprecision of less than 10 %. There was good agreement between the new high sensitive immunofluorometric assay (IFMA) and two well-established Tg assays from Brahms Kryptor and Roche Diagnostics. Mean difference between the new IFMA and the Kryptor assay was 0.059 μg/l with a 95 % confidence interval of -0.032 to 0.151 μg/l, whereas the mean difference between the new IFMA and the Roche assay was -0.80 μg/l with a 95 % confidence interval of -1.24 to -0.35 μg/l.

  15. Effects of glyphosate and the glyphosate based herbicides Roundup Original(®) and Roundup Transorb(®) on respiratory morphophysiology of bullfrog tadpoles.

    Science.gov (United States)

    Rissoli, Rafael Zanelli; Abdalla, Fabio Camargo; Costa, Monica Jones; Rantin, Francisco Tadeu; McKenzie, David John; Kalinin, Ana Lucia

    2016-08-01

    Glyphosate-based herbicides are widely used in agriculture and are commonly found in water bodies. Roundup Original(®) (RO) contains an isopropylamine glyphosate (GLY) salt containing the surfactant POEA, while Roundup Transorb R(®) (RTR) contains a potassium salt of GLY with unknown surfactants. Both contain different compositions of so-called "inert" ingredients, more toxic than glyphosate. Amphibian tadpoles often experience variations in O2 availability in their aquatic habitats; an ability to tolerate hypoxia can condition their survival and fitness. We evaluated the impacts of sublethal concentrations of GLY (1 mg L(-1)), RO (1 mg L(-1) GLY a.e) and RTR (1 mg L(-1) GLY a.e) on metabolic rate (V·O2 - mLO2 Kg1 h(-1)) of bullfrog tadpoles during normoxia and graded hypoxia, and related this to morphology of their skin, their major site of gas exchange. In control (CT) V·O2 remained unaltered from normoxia until 40 mmHg, indicating a critical O2 tension between 40 and 20 mmHg. GLY significantly reduced V·O2, possibly due to epidermal hypertrophy, which increased O2 diffusion distance to O2 uptake. In contrast, RTR increased V·O2 during hypoxia, indicating an influence of "inert" compounds and surfactants. V·O2 of RO did not differ from CT, suggesting that any increase in V·O2 caused by exposure was antagonized by epidermal hypertrophy. Indeed, all herbicides caused marked alterations in skin morphology, with cell and epithelium wall presenting hyperplasia or hypertrophy and chromatid rupture. In summary, GLY, RO and RTR exert different effects in bullfrog tadpoles, in particular the surfactants and inert compounds appear to influence oxygen uptake.

  16. Effects of glyphosate and the glyphosate based herbicides Roundup Original(®) and Roundup Transorb(®) on respiratory morphophysiology of bullfrog tadpoles.

    Science.gov (United States)

    Rissoli, Rafael Zanelli; Abdalla, Fabio Camargo; Costa, Monica Jones; Rantin, Francisco Tadeu; McKenzie, David John; Kalinin, Ana Lucia

    2016-08-01

    Glyphosate-based herbicides are widely used in agriculture and are commonly found in water bodies. Roundup Original(®) (RO) contains an isopropylamine glyphosate (GLY) salt containing the surfactant POEA, while Roundup Transorb R(®) (RTR) contains a potassium salt of GLY with unknown surfactants. Both contain different compositions of so-called "inert" ingredients, more toxic than glyphosate. Amphibian tadpoles often experience variations in O2 availability in their aquatic habitats; an ability to tolerate hypoxia can condition their survival and fitness. We evaluated the impacts of sublethal concentrations of GLY (1 mg L(-1)), RO (1 mg L(-1) GLY a.e) and RTR (1 mg L(-1) GLY a.e) on metabolic rate (V·O2 - mLO2 Kg1 h(-1)) of bullfrog tadpoles during normoxia and graded hypoxia, and related this to morphology of their skin, their major site of gas exchange. In control (CT) V·O2 remained unaltered from normoxia until 40 mmHg, indicating a critical O2 tension between 40 and 20 mmHg. GLY significantly reduced V·O2, possibly due to epidermal hypertrophy, which increased O2 diffusion distance to O2 uptake. In contrast, RTR increased V·O2 during hypoxia, indicating an influence of "inert" compounds and surfactants. V·O2 of RO did not differ from CT, suggesting that any increase in V·O2 caused by exposure was antagonized by epidermal hypertrophy. Indeed, all herbicides caused marked alterations in skin morphology, with cell and epithelium wall presenting hyperplasia or hypertrophy and chromatid rupture. In summary, GLY, RO and RTR exert different effects in bullfrog tadpoles, in particular the surfactants and inert compounds appear to influence oxygen uptake. PMID:27160633

  17. Pool of resistance mechanisms to glyphosate in Digitaria insularis.

    Science.gov (United States)

    de Carvalho, Leonardo Bianco; Alves, Pedro Luis da Costa Aguiar; González-Torralva, Fidel; Cruz-Hipolito, Hugo Enrique; Rojano-Delgado, Antonia María; De Prado, Rafael; Gil-Humanes, Javier; Barro, Francisco; de Castro, María Dolores Luque

    2012-01-18

    Digitaria insularis biotypes resistant to glyphosate have been detected in Brazil. Studies were carried out in controlled conditions to determine the role of absorption, translocation, metabolism, and gene mutation as mechanisms of glyphosate resistance in D. insularis. The susceptible biotype absorbed at least 12% more (14)C-glyphosate up to 48 h after treatment (HAT) than resistant biotypes. High differential (14)C-glyphosate translocation was observed at 12 HAT, so that >70% of the absorbed herbicide remained in the treated leaf in resistant biotypes, whereas 42% remained in the susceptible biotype at 96 HAT. Glyphosate was degraded to aminomethylphosphonic acid (AMPA), glyoxylate, and sarcosine by >90% in resistant biotypes, whereas a small amount of herbicide (up to 11%) was degraded by the susceptible biotype up to 168 HAT. Two amino acid changes were found at positions 182 and 310 in EPSPS, consisting of a proline to threonine and a tyrosine to cysteine substitution, respectively, in resistant biotypes. Therefore, absorption, translocation, metabolism, and gene mutation play an important role in the D. insularis glyphosate resistance.

  18. 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

  19. Studies on a new group of biodegradable surfactants for glyphosate.

    Science.gov (United States)

    Haefs, Roland; Schmitz-Eiberger, Michaela; Mainx, Hans-G; Mittelstaedt, Werner; Noga, Georg

    2002-08-01

    The effectiveness of a homologous series of biodegradable rapeseed oil derivatives (triglyceride ethoxylates; Agnique RSO series containing an average of 5, 10, 30 and 60 units of ethylene oxide (EO) as adjuvants for foliage-applied, water-soluble, systemic active ingredients was evaluated employing glyphosate as an example. Previous experiments had revealed that the surfactants used are not phytotoxic at concentrations ranging from 1 to 10 g litre-1. The experiments were performed using Phaseolus vulgaris L and nine selected weed species, grown in a growth chamber at 25/20 (+/- 2) degrees C day/night temperature and 40/70 (+/- 10)% relative humidity. The surfactants were evaluated for enhancement of spray retention, and foliar penetration biological efficacy of glyphosate. Glyphosate was applied at a concentration of 43 mM. The surfactants were added at concentrations of 1 g litre-1. The commercial glyphosate 360 g AE litre-1 SL Roundup Ultra and unformulated glyphosate served as references. The surfactants used improved spray retention, foliar penetration and biological efficacy. Some of the formulations were comparable to the performance of Roundup Ultra in the aspects evaluated; some were even more effective in enhancing spray liquid retention and promoting glyphosate phytotoxicity in several plant species. In these studies Agnique RSO 60 generally was most effective. PMID:12192908

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

    Science.gov (United States)

    Mamy, Laure; Gabrielle, Benoît; Barriuso, Enrique

    2010-10-01

    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.

  1. Loss of glyphosate efficacy: a changing weed spectrum in Georgia cotton

    Science.gov (United States)

    Introduction of glyphosate resistance into crops through genetic modification has revolutionized crop protection. Glyphosate, the proverbial silver bullet, is a broad spectrum herbicide with favorable environmental characteristics and effective broad-spectrum weed control that has greatly improved ...

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

    OpenAIRE

    Mamy, Laure; Gabrielle, Benoit; Barriuso Benito, Enrique,

    2010-01-01

    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...

  3. 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...

  4. 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.

  5. 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.

  6. 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...

  7. Influencing factors on regional differences in glyphosate use in North German arable farming

    OpenAIRE

    Andert, Sabine; Bürger, Jana; Gerowitt, Bärbel

    2016-01-01

    Glyphosate is the worldwide mostly used herbicide substance. Glyphosate use in arable cropping is under strong discussion in scientific and public communities. In the present study, we investigated the use of glyphosate from 15 farms in four districts in North German arable farming from 2005 until 2014. Objective of our research is to reveal influencing factors on glyphosate use intensity. The farm structures differ between two West districts (Diepholz, Uelzen) and two East districts (Fläm...

  8. 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...

  9. The Economics of Glyphosate Resistance Management in Corn and Soybean Production

    OpenAIRE

    Livingston, Michael; Fernandez-Cornejo, Jorge; Unger, Jesse; Osteen, Craig; Schimmelpfennig, David; Park, Tim; Lambert, Dayton

    2015-01-01

    Glyphosate, known by many trade names, including Roundup, is a highly effective herbicide. Widespread glyphosate use for corn and soybean has led to glyphosate resistance, which is now documented in 14 weed species affecting U.S. cropland, and recent surveys suggest that acreage with glyphosate-resistant (GR) weeds is expanding. Data from USDA’s Agricultural Resource Management Survey (ARMS), along with the Benchmark Study (conducted independently by plant scientists), are used to address sev...

  10. Biodegradation of glyphosate herbicide by Salinicoccus spp isolated from Qom Hoze-soltan lake, Iran

    OpenAIRE

    Yaser Sharifi; Ahmad Ali Pourbabaei; Ali Javadi; Mohammad Hossein Abdolmohammadi; Mehri Saffari; Abbas Morovvati

    2015-01-01

    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 d...

  11. 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...

  12. Photo- and biophysical studies of lectin-conjugated fluorescent nanoparticles: reduced sensitivity in high density assays.

    Science.gov (United States)

    Wang, Yaqi; Gildersleeve, Jeffrey C; Basu, Amit; Zimmt, Matthew B

    2010-11-18

    Lectin-conjugated, fluorescent silica nanoparticles (fNP) have been developed for carbohydrate-based histopathology evaluations of epithelial tissue biopsies. The fNP platform was selected for its enhanced emissive brightness compared to direct dye labeling. Carbohydrate microarray studies were performed to compare the carbohydrate selectivity of the mannose-recognizing lectin Concanavalin A (ConA) before and after conjugation to fluorescent silica nanoparticles (ConA-fNP). These studies revealed surprisingly low emission intensities upon staining with ConA-fNP compared to those with biotin-ConA/Cy3-streptavidin staining. A series of photophysical and biophysical characterizations of the fNP and ConA-fNP conjugates were performed to probe the low sensitivity from fNP in the microarray assays. Up to 1200 fluorescein (FL) and 80 tetramethylrhodamine (TR) dye molecules were incorporated into 46 nm diameter fNP, yielding emissive brightness values 400 and 35 times larger than the individual dye molecules, respectively. ConA lectin conjugated to carboxylic acid surface-modified nanoparticles covers 15-30% of the fNP surface. The CD spectra and mannose substrate selectivity of ConA conjugated to the fNP differed slightly compared to that of soluble ConA. Although, the high emissive brightness of fNP enhances detection sensitivity for samples with low analyte densities, large fNP diameters limit fNP recruitment and binding to samples with high analyte densities. The high analyte density and nearly two-dimensional target format of carbohydrate microarrays make probe size a critical parameter. In this application, fNP labels afford minimal sensitivity advantage compared to direct dye labeling.

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

    DEFF Research Database (Denmark)

    Møller, Søren; Iversen, Jens S; Krag, Aleksander;

    2010-01-01

    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...... 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...

  14. 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

    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.

  15. Mechanism Of Resistance Of Evolved Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri L.)

    Science.gov (United States)

    Evolved glyphosate resistance in weedy species represents a challenge for the continued success and utility of glyphosate-resistant crops. The first case of evolved glyphosate resistance in Palmer amaranth was a population from the U.S. state of Georgia, which was previously reported to have amplif...

  16. 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...

  17. 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, ...

  18. 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...

  19. 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 l...

  20. Effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-jun; ZHOU Dong-mei; SUN Rui-juan

    2005-01-01

    Glyphosate (GPS) is a non-selective, post-mergence herbicide that is widely used throughout the world. Due to the similar molecular structures of glyphosate and phosphate, adsorption of glyphosate on soil is easily affected by coexisting phosphate, especially when phosphate is applied at a significant rate in farmland. This paper studied the effects of phosphate on the adsorption of glyphosate on three different types of Chinese soils including two variable charge soils and one permanent charge soil. The results indicated that Freundlich equations used to simulate glyphosate adsorption isotherms gave high correlation coefficients(0.990-0.998) with K values of 2751, 2451 and 166 for the zhuanhong soil(ZH soil, Laterite), red soil(RS, Udic Ferrisol) and Wushan paddy soil(WS soil, Anthrosol),respectively. The more the soil iron and aluminum oxides and clay contained, the more glyphosate adsorbed. The presence of phosphate significantly decreased the adsorption of glyphosate to the soils by competing with glyphosate for adsorption sites of soils. Meanwhile, the effects of phosphate on adsorption of glyphosate on the two variable charge soils were more significant than that on the permanent charge soil. When phosphate and glyphosate were added in the soils in different orders, the adsorption quantities of glyphosate on the soils were different, which followed GPS-soil>GPS-P-soil = GPS-soil-P > P-soil-GPS, meaning a complex interaction occurred among glyphosate,phosphate and the soils.

  1. Prowashonupana barley dietary fibre reduces body fat and increases insulin sensitivity in Caenorhabditis elegans model

    Science.gov (United States)

    Gao, Chenfei; King, Michael L.; Fitzpatrick, Zachary L.; Wei, Wenqian; King, Jason F.; Wang, Mingming; Greenway, Frank L.; Finley, John W.; Johnson, William D.; Keenan, Michael J.; Enright, Frederick M.; Martin, Roy J.; Zheng, Jolene

    2016-01-01

    Prowashonupana barley (PWB) is high in β-glucan with moderate content of resistant starch. PWB reduced intestinal fat deposition (IFD) in wild type Caenorhabditis elegans (C. elegans, N2), and in sir-2.1 or daf-16 null mutants, and sustained a surrogate marker of lifespan, pharyngeal pumping rate (PPR), in N2, sir-2.1, daf-16, or daf-16/daf-2 mutants. Hyperglycaemia (2% glucose) reversed or reduced the PWB effect on IFD in N2 or daf-16/daf-2 mutants with a sustained PPR. mRNA expression of cpt-1, cpt-2, ckr-1, and gcy-8 were dose-dependently reduced in N2 or daf-16 mutants, elevated in daf-16/daf-2 mutants with reduction in cpt-1, and unchanged in sir-2.1 mutants. mRNA expressions were increased by hyperglycaemia in N2 or daf-16/daf-2 mutants, while reduced in sir-2.1 or daf-16 mutants. The effects of PWB in the C. elegans model appeared to be primarily mediated via sir-2.1, daf-16, and daf-16/daf-2. These data suggest that PWB and β-glucans may benefit hyperglycaemia-impaired lipid metabolism.

  2. Lactococcus lactis NCC 2287 Alleviates Food Allergic Manifestations in Sensitized Mice by Reducing IL-13 Expression Specifically in the Ileum

    Directory of Open Access Journals (Sweden)

    Adrian W. Zuercher

    2012-01-01

    Full Text Available Objective. Utilizing a food allergy murine model, we have investigated the intrinsic antiallergic potential of the Lactococcus lactis NCC 2287 strain. Methods. BALB/c mice were sensitized at weekly intervals with ovalbumin (OVA plus cholera toxin (CT by the oral route for 7 weeks. In this model, an oral challenge with a high dose of OVA at the end of the sensitization period leads to clinical symptoms. Lactococcus lactis NCC 2287 was given to mice via the drinking water during sensitization (prevention phase or after sensitization (management phase. Results. Lactococcus lactis NCC 2287 administration to sensitized mice strikingly reduced allergic manifestations in the management phase upon challenge, when compared to control mice. No preventive effect was observed with the strain. Lactococcus lactis NCC 2287 significantly decreased relative expression levels of the Th-2 cytokine, IL-13, and associated chemokines CCL11 (eotaxin-1 and CCL17 (TARC in the ileum. No effect was observed in the jejunum. Conclusion/Significance. These results taken together designate Lactococcus lactis NCC 2287 as a candidate probiotic strain appropriate in the management of allergic symptoms.

  3. Degradation and Isotope Source Tracking of Glyphosate and Aminomethylphosphonic Acid.

    Science.gov (United States)

    Li, Hui; Joshi, Sunendra R; Jaisi, Deb P

    2016-01-27

    Glyphosate [N-(phosphonomethyl) glycine], an active ingredient of the herbicide Roundup, and its main metabolite, aminomethylphosphonic acid (AMPA), have been frequently reported to be present in soils and other environments and thus have heightened public concerns on their potential adverse effects. Understanding the fate of these compounds and differentiating them from other naturally occurring compounds require a toolbox of methods that can go beyond conventional methods. Here, we applied individual isotope labeling technique whereby each compound or mineral involved in the glyphosate and AMPA degradation reaction was either synthesized or chosen to have distinct (18)O/(16)O ratios so that the source of incorporated oxygen in the orthophosphate generated and corresponding isotope effect during C-P bond cleavage could be identified. Furthermore, we measured original isotope signatures of a few commercial glyphosate sources to identify their source-specific isotope signatures. Our degradation kinetics results showed that the rate of glyphosate degradation was higher than that of AMPA in all experimental conditions, and both the rate and extent of degradation were lowest under anoxic conditions. Oxygen isotope ratios (δ(18)OP) of orthophosphate generated from glyphosate and AMPA degradation suggested that one external oxygen atom from ambient water, not from dissolved oxygen or mineral, was incorporated into orthophosphate with the other three oxygen atoms inherited from the parent molecule. Interestingly, δ(18)OP values of all commercial glyphosate products studied were found to be the lightest among all orthophosphates known so far. Furthermore, isotope composition was found to be unaffected due to variable degradation kinetics, light/dark, and oxic/anoxic conditions. These results highlight the importance of phosphate oxygen isotope ratios as a nonconventional tool to potentially distinguish glyphosate sources and products from other organophosphorus compounds

  4. 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.

  5. 7-week aerobic exercise training reduces adipocyte area and improves insulin sensitivity in Wistar rats fed a highly palatable diet

    Directory of Open Access Journals (Sweden)

    Nádia F. Garcia

    2016-03-01

    Full Text Available Abstract The aim of this study was to evaluate the effect aerobic exercise training on fat pad mass, adipocyte size, leptin release and insulin sensitivity in rats fed with high fat-palatable diet. Twenty-four male Wistar rats (250-260g were divided into four groups: sedentary control (CTR/SD, trained control (CTR/TR, obese sedentary (OB/SD and obese trained (OB/TR. Obese groups were fed with high fat-palatable diet (27% of fat and control groups fed with AIN-93. Our results showed that aerobic exercise training was effective to reduce body weight and epididymal fat mass in CTR/TR and OB/TR. Insulin and glucose levels were increased in OB/TR compared with OB/SD. Aerobic exercise training reduced the average area of adipocytes in CTR/TR and OB/TR and it was associated with reduced plasma insulin and leptin. In conclusion, 7-week aerobic exercise training reduces adipocyte area and improves insulin sensitivity and leptin levels in high fat-palatable diet-fed Wistar rats.

  6. Amplified photoacoustic performance and enhanced photothermal stability of reduced graphene oxide coated gold nanorods for sensitive photoacoustic imaging.

    Science.gov (United States)

    Moon, Hyungwon; Kumar, Dinesh; Kim, Haemin; Sim, Changbeom; Chang, Jin-Ho; Kim, Jung-Mu; Kim, Hyuncheol; Lim, Dong-Kwon

    2015-03-24

    We report a strongly amplified photoacoustic (PA) performance of the new functional hybrid material composed of reduced graphene oxide and gold nanorods. Due to the excellent NIR light absorption properties of the reduced graphene oxide coated gold nanorods (r-GO-AuNRs) and highly efficient heat transfer process through the reduced graphene oxide layer, r-GO-AuNRs exhibit excellent photothermal stability and significantly higher photoacoustic amplitudes than those of bare-AuNRs, nonreduced graphene oxide coated AuNRs (GO-AuNRs), or silica-coated AuNR, as demonstrated in both in vitro and in vivo systems. The linear response of PA amplitude from reduced state controlled GO on AuNR indicates the critical role of GO for a strong photothermal effect of r-GO-AuNRs. Theoretical studies with finite-element-method lab-based simulation reveal that a 4 times higher magnitude of the enhanced electromagnetic field around r-GO-AuNRs can be generated compared with bare AuNRs or GO-AuNRs. Furthermore, the r-GO-AuNRs are expected to be a promising deep-tissue imaging probe because of extraordinarily high PA amplitudes in the 4-11 MHz operating frequency of an ultrasound transducer. Therefore, the r-GO-AuNRs can be a useful imaging probe for highly sensitive photoacoustic images and NIR sensitive therapeutics based on a strong photothermal effect.

  7. Rezistence turanky kanadské vůči účinné látce glyphosate

    OpenAIRE

    Jeřábková, Julie

    2013-01-01

    My thesis is called ,,Glyphosate resistance in Conyza canadensis‘‘ and deals with issues of evolved herbicide-resistant weeds, specifically glyphosate-resistant Conyza canadensis. The objective of this thesis was to assess the susceptibility of Conyza canadensis to glyphosate experimentally. The thesis starts with an overview of the discovery of glyphosate, development, applications, its properties and the development of transgenic glyphosate-resistant crops. The next chapters take a closer l...

  8. Herbicide-resistant weed management: focus on glyphosate.

    Science.gov (United States)

    Beckie, Hugh J

    2011-09-01

    This review focuses on proactive and reactive management of glyphosate-resistant (GR) weeds. Glyphosate resistance in weeds has evolved under recurrent glyphosate usage, with little or no diversity in weed management practices. The main herbicide strategy for proactively or reactively managing GR weeds is to supplement glyphosate with herbicides of alternative modes of action and with soil-residual activity. These herbicides can be applied in sequences or mixtures. Proactive or reactive GR weed management can be aided by crop cultivars with alternative single or stacked herbicide-resistance traits, which will become increasingly available to growers in the future. Many growers with GR weeds continue to use glyphosate because of its economical broad-spectrum weed control. Government farm policies, pesticide regulatory policies and industry actions should encourage growers to adopt a more proactive approach to GR weed management by providing the best information and training on management practices, information on the benefits of proactive management and voluntary incentives, as appropriate. Results from recent surveys in the United States indicate that such a change in grower attitudes may be occurring because of enhanced awareness of the benefits of proactive management and the relative cost of the reactive management of GR weeds.

  9. Skin decontamination of glyphosate from human skin in vitro.

    Science.gov (United States)

    Zhai, H; Chan, H P; Hui, X; Maibach, H I

    2008-06-01

    This study compared three model decontaminant solutions (tap water, isotonic saline, and hypertonic saline) for their ability to remove a model herbicide (glyphosate) from an in vitro human skin model. Human cadaver skin was dosed (approximately 375microg) of [14C]-glyphosate on 3cm2 per skin. After each exposure time (1, 3, and 30min post-dosing, respectively), the surface skin was washed three times (4ml per time) with each solution. After washing, the skin was stripped twice with tape discs. Lastly, the wash solutions, strippings, receptor fluid, and remainder of skin were liquid scintillation analyzer counted to determine the amount of glyphosate. There were no statistical differences among these groups at any time points. The total mass balance recovery at three time exposure points was between 94.8% and 102.4%. The wash off rates (glyphosate in wash solutions) at three different exposure times is 79-101.2%. Thus the three tested decontaminants possess similar effectiveness in removing glyphosate from skin. This in vitro model is not only economic and rapid, but also provides quantitative data that may aid screening for optimal decontaminants. PMID:18407393

  10. Effect of manure on glyphosate and trifluralin mineralization in soil.

    Science.gov (United States)

    Reimer, M; Farenhorst, A; Gaultier, J

    2005-01-01

    Manure additions to soil may alter soil chemical, physical, and biological characteristics, and thereby change pesticide fate processes in soil. This is the first study to examine the impact of liquid hog manure amendments on glyphosate and trifluralin mineralization in soil. Experiments were conducted in soil microcosms in the laboratory for a total of 332 (glyphosate) and 430 (trifluralin) days. The rate and amount of mineralization of both glyphosate and trifluralin were significantly influenced by the additions of fresh manure to soil in the laboratory and by the history of manure applications in the field. However, the maximum difference in herbicide mineralization between soils that were free of manure application and those amended with manure in the field or in the laboratory was only 6.1% and 7.3% of that initially applied, for trifluralin and glyphosate, respectively. Therefore, we conclude that liquid hog manure application to soil will have no significant effect on the mineralization of glyphosate and trifluralin under field conditions.

  11. Herbicide-resistant weed management: focus on glyphosate.

    Science.gov (United States)

    Beckie, Hugh J

    2011-09-01

    This review focuses on proactive and reactive management of glyphosate-resistant (GR) weeds. Glyphosate resistance in weeds has evolved under recurrent glyphosate usage, with little or no diversity in weed management practices. The main herbicide strategy for proactively or reactively managing GR weeds is to supplement glyphosate with herbicides of alternative modes of action and with soil-residual activity. These herbicides can be applied in sequences or mixtures. Proactive or reactive GR weed management can be aided by crop cultivars with alternative single or stacked herbicide-resistance traits, which will become increasingly available to growers in the future. Many growers with GR weeds continue to use glyphosate because of its economical broad-spectrum weed control. Government farm policies, pesticide regulatory policies and industry actions should encourage growers to adopt a more proactive approach to GR weed management by providing the best information and training on management practices, information on the benefits of proactive management and voluntary incentives, as appropriate. Results from recent surveys in the United States indicate that such a change in grower attitudes may be occurring because of enhanced awareness of the benefits of proactive management and the relative cost of the reactive management of GR weeds. PMID:21548004

  12. 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

  13. 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.

  14. Reducing health disparities through culturally sensitive treatment for HIV+ adults in Haiti.

    Science.gov (United States)

    Devieux, Jessy G; Malow, Robert M; Jean-Gilles, Michele M; Samuels, Deanne M; Deschamps, Marie-Marcelle; Ascencio, Maxi; Jean-Baptiste, Larissa; Pape, Jean William

    2004-01-01

    There is a critical need to deliver empirically validated interventions to underserved populations. Haiti, the country most heavily affected by the AIDS epidemic in the Caribbean, accounts for approximately 50% of all cases in the region. Poverty, disparities in access to healthcare, and socio-political instability are among the reasons why the country has been ravaged by the disease. Ongoing projects in Haiti have shown that integrated prevention and care in resource poor settings are feasible and can be successful, as evidenced by a 50% drop in incidence among pregnant women since 1993. The AIDS prevention program has embarked on a comprehensive effort to culturally adapt a cognitive-behavioral stress management program for Haitian HIV+ individuals. The purpose of the program is to improve adherence to antiretroviral medication, reduce transmission to uninfected partners, and improve coping. This comprehensive approach is necessary to ensure the validity of the cross-cultural adaptation of this intervention.

  15. Evidence summary: which dental liners under amalgam restorations are more effective in reducing postoperative sensitivity?

    Science.gov (United States)

    Nasser, Mona

    2011-06-10

    Since August 2009, members of the Primary Care Dentistry Research Forum (www.dentistryresearch.org) have taken part in an online vote to identify questions in day-to-day practice that they felt most needed to be answered with conclusive research. The question that receives the most votes each month forms the subject of a critical appraisal of the relevant literature. Each month a new round of voting takes place to decide which further questions will be reviewed. Dental practitioners and dental care professionals are encouraged to take part in the voting and submit their own questions to be included in the vote by joining the website. The paper below details a summary of the findings of the ninth critical appraisal. In order to address the question raised by dentistry research forum, first a search was conducted for systematic reviews on the topic. There was one systematic review retrieved comparing bonded amalgam restorations versus non-bonded amalgam restorations. However, there was no other systematic review identified assessing the effectiveness of dental liners under amalgam restorations in general. Therefore, a search was conducted for any randomised controlled trial (RCT) comparing use of a lining under amalgam restorations versus no lining or RCTs comparing differing lining materials under amalgam against each other. There were eight relevant RCTs identified. Due to the low quality, small sample sizes or lack of adequate reporting of the outcome data, the evidence is inadequate to claim or refute a difference in postoperative sensitivity between different dental liners. Further well-conducted RCTs are needed to answer this question. These RCTs would be preferably included and synthesised in a systematic review.

  16. 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

  17. 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

  18. 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.

  19. How can we reduce phosphorus export from lowland polders? Implications from a sensitivity analysis of a coupled model.

    Science.gov (United States)

    Huang, Jiacong; Gao, Junfeng; Yan, Renhua

    2016-08-15

    Phosphorus (P) export from lowland polders has caused severe water pollution. Numerical models are an important resource that help water managers control P export. This study coupled three models, i.e., Phosphorus Dynamic model for Polders (PDP), Integrated Catchments model of Phosphorus dynamics (INCA-P) and Universal Soil Loss Equation (USLE), to describe the P dynamics in polders. Based on the coupled models and a dataset collected from Polder Jian in China, sensitivity analysis were carried out to analyze the cause-effect relationships between environmental factors and P export from Polder Jian. The sensitivity analysis results showed that P export from Polder Jian were strongly affected by air temperature, precipitation and fertilization. Proper fertilization management should be a strategic priority for reducing P export from Polder Jian. This study demonstrated the success of model coupling, and its application in investigating potential strategies to support pollution control in polder systems.

  20. How can we reduce phosphorus export from lowland polders? Implications from a sensitivity analysis of a coupled model.

    Science.gov (United States)

    Huang, Jiacong; Gao, Junfeng; Yan, Renhua

    2016-08-15

    Phosphorus (P) export from lowland polders has caused severe water pollution. Numerical models are an important resource that help water managers control P export. This study coupled three models, i.e., Phosphorus Dynamic model for Polders (PDP), Integrated Catchments model of Phosphorus dynamics (INCA-P) and Universal Soil Loss Equation (USLE), to describe the P dynamics in polders. Based on the coupled models and a dataset collected from Polder Jian in China, sensitivity analysis were carried out to analyze the cause-effect relationships between environmental factors and P export from Polder Jian. The sensitivity analysis results showed that P export from Polder Jian were strongly affected by air temperature, precipitation and fertilization. Proper fertilization management should be a strategic priority for reducing P export from Polder Jian. This study demonstrated the success of model coupling, and its application in investigating potential strategies to support pollution control in polder systems. PMID:27148646

  1. 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.

  2. 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

    2015-11-23

    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.

  3. Comparative toxicity of two glyphosate-based formulations to Eisenia andrei under laboratory conditions.

    Science.gov (United States)

    Piola, Lucas; Fuchs, Julio; Oneto, María Luisa; Basack, Silvana; Kesten, Eva; Casabé, Norma

    2013-04-01

    Glyphosate-based products are the leading post-emergent agricultural herbicides in the world, particularly in association with glyphosate tolerant crops. However, studies on the effects of glyphosate-based formulations on terrestrial receptors are scarce. This study was conducted to evaluate the comparative toxicity of two glyphosate-based products: Roundup FG (monoammonium salt, 72% acid equivalent, glyphosate-A) and Mon 8750 (monoammonium salt, 85.4% acid equivalent, glyphosate-B), towards the earthworm Eisenia andrei. Median lethal concentration (LC50) showed that glyphosate-A was 4.5-fold more toxic than glyphosate-B. Sublethal concentrations caused a concentration-dependent weight loss, consistent with the reported effect of glyphosate as uncoupler of oxidative phosphorylation. Glyphosate-A showed deleterious effects on DNA and lysosomal damage at concentrations close to the applied environmental concentrations (14.4 μg ae cm(-2)). With glyphosate-B toxic effects were observed at higher doses, close to its LC50, suggesting that the higher toxicity of formulate A could be attributed to the effects of some of the so-called "inert ingredients", either due to a direct intrinsic toxicity, or to an enhancement in the bioavailability and/or bioaccumulation of the active ingredient. Our results highlight the importance of ecotoxicological assessment not only of the active ingredients, but also of the different formulations usually employed in agricultural practices. PMID:23332878

  4. A novel P106L mutation in EPSPS and an unknown mechanism(s) act additively to confer resistance to glyphosate in a South African Lolium rigidum population.

    Science.gov (United States)

    Kaundun, Shiv S; Dale, Richard P; Zelaya, Ian A; Dinelli, Giovanni; Marotti, Ilaria; McIndoe, Eddie; Cairns, Andrew

    2011-04-13

    Glyphosate resistance evolution in weeds is a growing problem in world agriculture. Here, we have investigated the mechanism(s) of glyphosate resistance in a Lolium rigidum population (DAG1) from South Africa. Nucleotide sequencing revealed the existence of at least three EPSPS homologues in the L. rigidum genome and identified a novel proline 106 to leucine substitution (P106L) in 52% DAG1 individuals. This mutation conferred a 1.7-fold resistance increase to glyphosate at the whole plant level. Additionally, a 3.1-fold resistance increase, not linked to metabolism or translocation, was estimated between wild-type P106-DAG1 and P106-STDS sensitive plants. Point accepted mutation analysis suggested that other amino acid substitutions at EPSPS position 106 are likely to be found in nature besides the P106/S/A/T/L point mutations reported to date. This study highlights the importance of minor mechanisms acting additively to confer significant levels of resistance to commercial field rates of glyphosate in weed populations subjected to high selection pressure.

  5. Uses of glyphosate in German arable farming – aspects of weed management and arable practice

    Directory of Open Access Journals (Sweden)

    Wiese, Armin

    2016-02-01

    Full Text Available Data on glyphosate use, personal attitudes and farm characteristics were collected in a Germany-wide inventory from 2026 farms. About 1700 farms could be analyzed in detail. Categories of glyphosate users were split into: non-users, low proportion users and high proportion users. The latter apply glyphosate on > 20% of their arable land are characterized by a high amount of non-inversion tillage, low labor effort and aboveaverage farm size. Perennial weeds play a less important role for glyphosate use than managing weed populations that are regarded as less susceptible to regular herbicides. Non-users and users of glyphosate differ in their attitude towards the benefits of glyphosate and the amount of glyphosate use in agriculture.

  6. 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;

    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...

  7. mTOR Inhibition: Reduced Insulin Secretion and Sensitivity in a Rat Model of Metabolic Syndrome

    Science.gov (United States)

    Rovira, Jordi; Ramírez-Bajo, María Jose; Banon-Maneus, Elisenda; Moya-Rull, Daniel; Ventura-Aguiar, Pedro; Hierro-Garcia, Natalia; Lazo-Rodriguez, Marta; Revuelta, Ignacio; Torres, Armando; Oppenheimer, Federico; Campistol, Josep M.; Diekmann, Fritz

    2016-01-01

    Background Sirolimus (SRL) has been associated with new-onset diabetes mellitus after transplantation. The aim was to determine the effect of SRL on development of insulin resistance and β-cell toxicity. Methods Lean Zucker rat (LZR) and obese Zucker rat (OZR) were distributed into groups: vehicle and SRL (0.25, 0.5, or 1.0 mg/kg) during 12 or 28 days. Intraperitoneal glucose tolerance test (IPGTT) was evaluated at days 0, 12, 28, and 45. Islet morphometry, β-cell proliferation, and apoptosis were analyzed at 12 days. Islets were isolated to analyze insulin content, insulin secretion, and gene expression. Results After 12 days, SRL treatment only impaired IPGTT in a dose-dependent manner in OZR. Treatment prolongation induced increase of area under the curve of IPGTT in LZR and OZR; however, in contrast to OZR, LZR normalized glucose levels after 2 hours. The SRL reduced pancreas weight and islet proliferation in LZR and OZR as well as insulin content. Insulin secretion was only affected in OZR. Islets from OZR + SRL rats presented a downregulation of Neurod1, Pax4, and Ins2 gene. Genes related with insulin secretion remained unchanged or upregulated. Conclusions In conditions that require adaptive β-cell proliferation, SRL might reveal harmful effects by blocking β-cell proliferation, insulin production and secretion. These effects disappeared when removing the therapy. PMID:27500257

  8. Enhanced NH3-Sensitivity of Reduced Graphene Oxide Modified by Tetra-α-Iso-Pentyloxymetallophthalocyanine Derivatives

    Science.gov (United States)

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

    2015-09-01

    Three kinds of novel hybrid materials were prepared by noncovalent functionalized reduced graphene oxide (rGO) with tetra-α-iso-pentyloxyphthalocyanine copper (CuPc), tetra-α-iso-pentyloxyphthalocyanine nickel (NiPc) and tetra-α-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.

  9. Naringenin Inhibits Adipogenesis and Reduces Insulin Sensitivity and Adiponectin Expression in Adipocytes

    Directory of Open Access Journals (Sweden)

    Allison J. Richard

    2013-01-01

    Full Text Available Adipose tissue development and function are widely studied to examine the relationship between obesity and the metabolic syndrome. It is well documented that the inability of adipose tissue to properly increase its lipid storage capacity during the obese state can lead to metabolic dysfunction. In a blind screen of 425 botanicals, we identified naringenin as an inhibitor of adipocyte differentiation. Naringenin is one of the most abundant citrus flavonoids, and recent studies have demonstrated antihyperlipidemic capabilities. These studies have largely focused on the effects of naringenin on the liver. Our biochemical studies clearly demonstrate that naringenin inhibits adipogenesis and impairs mature fat cell function. Naringenin specifically inhibited adipogenesis in a dose-dependent fashion as judged by examining lipid accumulation and induction of adipocyte marker protein expression. In mature 3T3-L1 adipocytes, naringenin reduced the ability of insulin to induce IRS-1 tyrosine phosphorylation and substantially inhibited insulin-stimulated glucose uptake in a dose-dependent manner and over a time frame of 1.5 to 24 hours. Exposure to naringenin also inhibited adiponectin protein expression in mature murine and human adipocytes. Our studies have revealed that naringenin may have a negative impact on adipocyte-related diseases by limiting differentiation of preadipocytes, by significantly inducing insulin resistance, and by decreasing adiponectin expression in mature fat cells.

  10. Reduced sensitivity to contrast signals from the eye region in developmental prosopagnosia.

    Science.gov (United States)

    Fisher, Katie; Towler, John; Eimer, Martin

    2016-08-01

    Contrast-related signals from the eye region are known to be important for the processing of facial identity. Individuals with developmental prosopagnosia (DP) have severe face recognition problems, which may be linked to deficits in the perceptual processing of identity-related information from the eyes. We tested this hypothesis by measuring N170 components in DP participants and age-matched controls in response to face images where the contrast polarity of the eyes and of other face parts was independently manipulated. In different trials, participants fixated either the eye region or the lower part of a face. In the Control group, contrast-reversal of the eyes resulted in enhanced and delayed N170 components, irrespective of the contrast of other face parts and of gaze location. In the DP group, these effects of eye contrast on N170 amplitudes were strongly and significantly reduced, demonstrating that perceptual face processing in DP is less well tuned to contrast information from the eye region. Inverting the contrast of other parts of the face affected N170 amplitudes only when fixation was outside the eye region. This effect did not differ between the two groups, indicating that DPs are not generally insensitive to the contrast polarity of face images. These results provide new evidence that a selective deficit in detecting and analysing identity-related information provided by contrast signals from the eye region may contribute to the face recognition impairment in DP. PMID:27179151

  11. A cross-coupled-structure-based temperature sensor with reduced process variation sensitivity

    Institute of Scientific and Technical Information of China (English)

    Tie Meng; Cheng Xu

    2009-01-01

    An innovative,thermally-insensitive phenomenon of cascaded cross-coupled structures is found.And a novel CMOS temperature sensor based on a cross-coupled structure is proposed.This sensor consists of two different ring oscillators.The first ring oscillator generates pulses that have a period,changing linearly with temperature.Instead of using the system clock like in traditional sensors,the second oscillator utilizes a cascaded cross-coupled structure to generate temperature independent pulses to capture the result from the first oscillator.Due to the compensation between the two ring oscillators,errors caused by supply voltage variations and systematic process variations are reduced.The layout design of the sensor is based on the TSMC13G process standard cell library.Only three inverters are modified for proper channel width tuning without any other custom design.This allows for an easy integration of the sensor into cell-based chips.Post-layout simulations results show that an error lower than±1.1℃ can be achieved in the full temperature range from-40 to 120℃.As shown by SPICE simulations,the thermal insensitivity of the cross-coupled inverters can be realized for various TSMC technologies:0.25/μm,0.18μm,0.13μm,and 65 nm.

  12. Glyphosate in the rhizosphere-role of waiting times and different glyphosate binding forms in soils for phytotoxicity to non-target plants

    OpenAIRE

    Tesfamariam, Tsehaye; Bott, S.; ÇAKMAK, İsmail; Cakmak, Ismail; Roemheld, V.; Neumann, G.

    2009-01-01

    Glyphosate is the most widely used non-selective, systemic herbicide. It is easily translocated from shoot to roots and released into the rhizosphere, where it is immobilized at the soil matrix or microbially degraded. However, contradictory results are reported in the literature concerning the bio-availability of glyphosate residues in soils and the potential risks for intoxication of non-target organisms. This study addresses the question whether plant residues of glyphosate-treated weeds (...

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

    Directory of Open Access Journals (Sweden)

    Anthony Samsel

    2015-01-01

    Full Text Available 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.

  14. Glyphosate-resistant crops: history, status and future.

    Science.gov (United States)

    Dill, Gerald M

    2005-03-01

    The commercial launch of glyphosate-resistant soybeans in 1996 signaled the beginning of a new era in weed management in row crops. Today, over 80% of the soybeans grown in the USA are glyphosate resistant. Since that time, many crops have been transformed that have allowed crop applications of many classes of herbicide chemistries. Crops currently under production include maize, soybean, cotton and canola. Transformation technology and selection methods have improved and the rate of development as well as the breadth of crops being considered as commercial targets has increased. On the basis of recent adoption rates by growers around the world, it appears that glyphosate-resistant crops will continue to grow in number and in hectares planted. However, global public acceptance of biotechnology-derived products will continue to impact the rate of adoption of this and other new innovations derived from transformation technology.

  15. 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

    Directory of Open Access Journals (Sweden)

    R.S. Oliveira JR.

    2008-01-01

    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.Glyphosate

  16. Toxic effects and exposurerisk assessment of glyphosate%草甘膦的毒性作用及暴露风险评估

    Institute of Scientific and Technical Information of China (English)

    黄少文; 柳春红

    2015-01-01

    This paper summarized the toxiceffects, toxic mechanism andexposure risk assessment of glyphosate, and some suggestions for further research were presented.Glyphosate may cause an effect or damage to organisms in the use process, and cause acute toxicity effect. Target organ toxicity of glyphosate mainly includes liver toxicity, reproductive toxicity and neurotoxicity. Glyphosate can reduce P450 enzyme activity in rat liver cytochromes, which may have toxic effects on the liver, and the reproductive toxicity of glyphosate may be caused by inhibition of aromatase activity and oxidative damage. The neurotoxic effects of glyphosate may be caused by the decrease of 5-HT in the brain. The glyphosate exposure level of Chinese population is 73.23 µg/kg bw by point assessment, accounted for 7.32% of China ADI, glyphosate does not pose ahealth risk to humans. The exposure risk assessment of glyphosate is still controversial, although there is a large literature which found no significant association between glyphosate and cancers, but also some literature reported the significant association between glyphosate exposure and non Hodgkin's lymphoma.%本文就草甘膦的毒性作用及其机制研究进展进行综述,并对草甘膦暴露风险作出了评估,最后对该领域的研究方向提出了展望。草甘膦在使用过程中可能会对生物体造成影响或危害,继而发生急性中毒;草甘膦的靶器官毒性作用主要包括肝毒性、生殖毒性和神经毒性作用,草甘膦能降低鼠肝细胞色素 P450酶活性,从而可能对肝脏产生毒性作用;草甘膦的生殖毒性作用可能是通过抑制芳香化酶的活性、产生氧化损伤等方面造成;草甘膦的神经毒性作用则可能是通过降低脑中5-羟色氨酸含量引起的。通过初步的点评估发现中国人群的草甘膦暴露水平为73.23µg/kg bw,占中国ADI(1 mg/kg bw)的7.32%,暂时没有暴露风险,虽有大量的文献研究发现草甘露暴露和

  17. 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 (λ ≥ 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

  18. 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.

  19. Controle de Brachiaria brizantha com uso do glyphosate após o estabelecimento de Tifton 85 (Cynodon spp. Control of Brachiaria brizantha with glyphosate's after Tifton's 85 (Cynodon spp. establishment

    Directory of Open Access Journals (Sweden)

    M.V. Santos

    2006-12-01

    efficiency on Brachiaria control were evaluated. At 60 DAA, the plants were cut and dried in a greenhouse, and the sprouts evaluated 60 days after cut. Under 738.28 g ha-1 of glyphosate, 90% of the Brachiaria brizantha plants were controlled, while Tifton plant intoxication was observed only at 12.05%. At 60 DAA, Brachiaria dry matter production decreased from 90 g ha-1 , with total control of these plants being observed at the rate of 738.28 g ha-1. Rates higher than 720 g ha-1 reduced the growth and development of Tifton 85, affecting its production without, however, leading to death of the plants. The results evidenced good selectivity for glyphosate to Tifton 85 culture up to 720 g ha-1.

  20. Study on pretreatment of the glyphosate wastewater and its engineering application%草甘膦废水预处理研究与工程应用

    Institute of Scientific and Technical Information of China (English)

    梅荣武; 韦彦斐; 沈浙萍; 陈雳华

    2012-01-01

    某草甘膦废水处理站已无法达到处理要求,需要进行改造.为了减轻后续的生化处理负荷,强化对草甘膦废水的除磷预处理,选用电絮凝氧化、Fenton氧化和电磁-Fenton氧化3种工艺作为草甘膦废水预处理工艺,进行了比选试验.试验结果表明,Fenton氧化为本工程的草甘膦废水最佳预处理工艺,可达到预期效果.%Some glyphosate wastewater treatment station could not meet the treatment requirements and needed to be upgraded. To reduce the biological treatment load of the following process, the dephosphorization - pretreatment process for glyphosate wastewater was enhanced. Three processes, including electric flocculation-oxidation, Fenton oxidation, and electromagnetism-Fen-ton oxidation were tested and studied to select the best pretreatment for glyphosate wastewater. The results showed: as the pretreatment for glyphosate wastewater in this project, Fenton oxidation could meet the expected standards.

  1. Glyphosate inhibition of ferric reductase activity in iron deficient sunflower roots.

    Science.gov (United States)

    Ozturk, Levent; Yazici, Atilla; Eker, Selim; Gokmen, Ozgur; Römheld, Volker; Cakmak, Ismail

    2008-01-01

    Iron (Fe) deficiency is increasingly being observed in cropping systems with frequent glyphosate applications. A likely reason for this is that glyphosate interferes with root uptake of Fe by inhibiting ferric reductase in roots required for Fe acquisition by dicot and nongrass species. This study investigated the role of drift rates of glyphosate (0.32, 0.95 or 1.89 mm glyphosate corresponding to 1, 3 and 6% of the recommended herbicidal dose, respectively) on ferric reductase activity of sunflower (Helianthus annuus) roots grown under Fe deficiency conditions. Application of 1.89 mm glyphosate resulted in almost 50% inhibition of ferric reductase within 6 h and complete inhibition 24 h after the treatment. Even at lower rates of glyphosate (e.g. 0.32 mm and 0.95 mm), ferric reductase was inhibited. Soluble sugar concentration and the NAD(P)H oxidizing capacity of apical roots were not decreased by the glyphosate applications. To our knowledge, this is the first study reporting the effects of glyphosate on ferric reductase activity. The nature of the inhibitory effect of glyphosate on ferric reductase could not be identified. Impaired ferric reductase could be a major reason for the increasingly observed Fe deficiency in cropping systems associated with widespread glyphosate usage.

  2. The effect of two glyphosate formulations on a small, diurnal lizard (Oligosoma polychroma).

    Science.gov (United States)

    Carpenter, Joanna K; Monks, Joanne M; Nelson, Nicola

    2016-04-01

    Formulations of glyphosate-based herbicides continue to dominate the global herbicide market, while there continue to be concerns regarding the impact of this herbicide on non-target organisms. Research also indicates that the additives within certain glyphosate formulations, such as surfactants, are actually more toxic than the glyphosate active ingredient alone. Concerns arise in particular when glyphosate formulations are proposed for vegetation control in areas inhabited by rare or threatened species. Although the effect of glyphosate on birds and mammals is well studied, reptiles remain neglected in ecotoxicological studies. We investigated whether dermal exposure to two different commercial glyphosate formulations affected performance measures in the New Zealand common skink (Oligosoma polychroma). Fifty-eight skinks were each placed in a box of straw to simulate field conditions and sprayed once with Agpro Glyphosate 360, Yates Roundup Weedkiller (both at the label-specified concentrations of 144 mg glyphosate per 1 L water), or water (control). Agpro Glyphosate 360 contained ethoxylated tallow amine at a concentration of <200 g/L, while the surfactant within Yates Roundup Weedkiller was unknown. Following treatment skinks were kept in captivity and sampled for selected temperature and mass over a four-week period. Neither glyphosate formulation had a significant impact on mass. However, skinks treated with Yates Roundup Weedkiller selected significantly higher temperatures across 3 weeks following exposure. This heat-seeking behaviour could be a fever response to increase metabolism and thereby counteract physiological stress. PMID:26841966

  3. The effect of two glyphosate formulations on a small, diurnal lizard (Oligosoma polychroma).

    Science.gov (United States)

    Carpenter, Joanna K; Monks, Joanne M; Nelson, Nicola

    2016-04-01

    Formulations of glyphosate-based herbicides continue to dominate the global herbicide market, while there continue to be concerns regarding the impact of this herbicide on non-target organisms. Research also indicates that the additives within certain glyphosate formulations, such as surfactants, are actually more toxic than the glyphosate active ingredient alone. Concerns arise in particular when glyphosate formulations are proposed for vegetation control in areas inhabited by rare or threatened species. Although the effect of glyphosate on birds and mammals is well studied, reptiles remain neglected in ecotoxicological studies. We investigated whether dermal exposure to two different commercial glyphosate formulations affected performance measures in the New Zealand common skink (Oligosoma polychroma). Fifty-eight skinks were each placed in a box of straw to simulate field conditions and sprayed once with Agpro Glyphosate 360, Yates Roundup Weedkiller (both at the label-specified concentrations of 144 mg glyphosate per 1 L water), or water (control). Agpro Glyphosate 360 contained ethoxylated tallow amine at a concentration of glyphosate formulation had a significant impact on mass. However, skinks treated with Yates Roundup Weedkiller selected significantly higher temperatures across 3 weeks following exposure. This heat-seeking behaviour could be a fever response to increase metabolism and thereby counteract physiological stress.

  4. Glyphosate-rich air samples induce IL-33, TSLP and generate IL-13 dependent airway inflammation.

    Science.gov (United States)

    Kumar, Sudhir; Khodoun, Marat; Kettleson, Eric M; McKnight, Christopher; Reponen, Tiina; Grinshpun, Sergey A; Adhikari, Atin

    2014-11-01

    Several low weight molecules have often been implicated in the induction of occupational asthma. Glyphosate, a small molecule herbicide, is widely used in the world. There is a controversy regarding a role of glyphosate in developing asthma and rhinitis among farmers, the mechanism of which is unexplored. The aim of this study was to explore the mechanisms of glyphosate induced pulmonary pathology by utilizing murine models and real environmental samples. C57BL/6, TLR4-/-, and IL-13-/- mice inhaled extracts of glyphosate-rich air samples collected on farms during spraying of herbicides or inhaled different doses of glyphosate and ovalbumin. The cellular response, humoral response, and lung function of exposed mice were evaluated. Exposure to glyphosate-rich air samples as well as glyphosate alone to the lungs increased: eosinophil and neutrophil counts, mast cell degranulation, and production of IL-33, TSLP, IL-13, and IL-5. In contrast, in vivo systemic IL-4 production was not increased. Co-administration of ovalbumin with glyphosate did not substantially change the inflammatory immune response. However, IL-13-deficiency resulted in diminished inflammatory response but did not have a significant effect on airway resistance upon methacholine challenge after 7 or 21 days of glyphosate exposure. Glyphosate-rich farm air samples as well as glyphosate alone were found to induce pulmonary IL-13-dependent inflammation and promote Th2 type cytokines, but not IL-4 for glyphosate alone. This study, for the first time, provides evidence for the mechanism of glyphosate-induced occupational lung disease.

  5. The Effects of Commercial Glyphosate Herbicide on the Seedlings of Transgenic Cotton with Glyphosate Resistance%市售草甘膦除草剂对转基因抗草甘膦棉花幼苗生长的影响

    Institute of Scientific and Technical Information of China (English)

    燕树锋; 陈进红; 梅磊; 周童童; 赵日峰; 祝水金

    2011-01-01

    以转基因抗草甘膦棉花种质系G6-7和G6-8及其非转基因遗传背景亲本对照中棉所49为材料,研究了市售10%草甘膦水剂和95%的草甘膦粉剂对抗草甘膦棉花种子萌发和幼苗生长的影响.结果表明,中棉所49对于两种类型的草甘膦均很敏感,幼苗喷施0.2 mmol· L-1的10%草甘膦水剂和95%草甘膦粉剂均全部死亡.转EPSPS-G6基因抗草甘膦棉对95%草甘膦粉剂的抗性较好,但对10%草甘膦水剂的抗性较弱.就转基因棉花对两种剂型草甘膦的反应看,喷施2.4 mmol- L-1的10%草甘膦水剂和95%草甘膦粉剂后,棉花幼苗全株鲜重、叶重、根重、下胚轴长、可溶性蛋白质增量和POD活性等各项指标在两种草甘膦制剂间的差异均达到显著水平.喷施12.0 mmol·L-1的10%草甘膦水剂,转基因抗草甘膦棉花的种子发芽率显著低于相同浓度的粉剂,两者之间的发芽率相差25%~75%.研究结果表明,10%的草甘膦水剂中可能含有对棉花幼苗生长发育有害的物质,影响抗草甘膦棉幼苗的生长,在转基因抗草甘膦棉花品种商业化应用时应谨慎使用.%The effects of two commercial glyphosates, 10% glyphosate aqueous solution and 95% glyphosate powder, on the seed germination and seedling growth of transgenic cotton with glyphosate resistance were studied, using the transgenic glyphosate-resistant cotton germplasm lines, G6-7 and G6-8, as the materials, and their non-transgenic genetic background culti-var, CCRI-49, as control. All the seedlings of CCRJ-49 died on the media with 0.2 mmol·L-1 10% glyphosate aqueous solution or 0.2 mmol·L-1 95% glyphosate powder, indicating that CCRI-49 is very sensitive to both types of glyphosate. The glyphosate resistant cotton germplasms with EPSPS-G6 gene expressed an excellent resistance to glyphosate when they were treated with 95% glyphosate powder, but were seriously damaged when treated with 10% glyphosate aqueous solution

  6. Adipose tissue dysregulation and reduced insulin sensitivity in non-obese individuals with enlarged abdominal adipose cells

    Directory of Open Access Journals (Sweden)

    Hammarstedt Ann

    2012-09-01

    Full Text Available Abstract Background Obesity contributes to Type 2 diabetes by promoting systemic insulin resistance. Obesity causes features of metabolic dysfunction in the adipose tissue that may contribute to later impairments of insulin action in skeletal muscle and liver; these include reduced insulin-stimulated glucose transport, reduced expression of GLUT4, altered expression of adipokines, and adipocyte hypertrophy. Animal studies have shown that expansion of adipose tissue alone is not sufficient to cause systemic insulin resistance in the absence of adipose tissue metabolic dysfunction. To determine if this holds true for humans, we studied the relationship between insulin resistance and markers of adipose tissue dysfunction in non-obese individuals. Method 32 non-obese first-degree relatives of Type 2 diabetic patients were recruited. Glucose tolerance was determined by an oral glucose tolerance test and insulin sensitivity was measured with the hyperinsulinaemic-euglycaemic clamp. Blood samples were collected and subcutaneous abdominal adipose tissue biopsies obtained for gene/protein expression and adipocyte cell size measurements. Results Our findings show that also in non-obese individuals low insulin sensitivity is associated with signs of adipose tissue metabolic dysfunction characterized by low expression of GLUT4, altered adipokine profile and enlarged adipocyte cell size. In this group, insulin sensitivity is positively correlated to GLUT4 mRNA (R = 0.49, p = 0.011 and protein (R = 0.51, p = 0.004 expression, as well as with circulating adiponectin levels (R = 0.46, 0 = 0.009. In addition, insulin sensitivity is inversely correlated to circulating RBP4 (R = −0.61, 0 = 0.003 and adipocyte cell size (R = −0.40, p = 0.022. Furthermore, these features are inter-correlated and also associated with other clinical features of the metabolic syndrome in the absence of obesity. No association could be found

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

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    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

  8. Foliar Potassium Fertilizer Additives Affect Soybean Response and Weed Control with Glyphosate

    Directory of Open Access Journals (Sweden)

    Kelly A. Nelson

    2012-01-01

    Full Text Available Research in 2004 and 2005 determined the effects of foliar-applied K-fertilizer sources (0-0-62-0 (%N-%P2O5-%K2O-%S, 0-0-25-17, 3-18-18-0, and 5-0-20-13 and additive rates (2.2, 8.8, and 17.6 kg K ha−1 on glyphosate-resistant soybean response and weed control. Field experiments were conducted at Novelty and Portageville with high soil test K and weed populations and at Malden with low soil test K and weed populations. At Novelty, grain yield increased with fertilizer additives at 8.8 kg K ha−1 in a high-yield, weed-free environment in 2004, but fertilizer additives reduced yield up to 470 kg ha−1 in a low-yield year (2005 depending on the K source and rate. At Portageville, K-fertilizer additives increased grain yield from 700 to 1160 kg ha−1 compared to diammonium sulfate, depending on the K source and rate. At Malden, there was no yield response to K sources. Differences in leaf tissue K (P=0.03, S (P=0.03, B (P=0.0001, and Cu (P=0.008 concentrations among treatments were detected 14 d after treatment at Novelty and Malden. Tank mixtures of K-fertilizer additives with glyphosate may provide an option for foliar K applications.

  9. Glyphosate sobre a resistência à ferrugem (Puccinia psidii do eucalipto Glyphosate on eucalyptus resistance to rust (Puccinia psidii

    Directory of Open Access Journals (Sweden)

    L.D. Tuffi Santos

    2007-03-01

    Full Text Available O glyphosate é o herbicida mais usado no controle de plantas daninhas em eucalipto, atuando diretamente na rota do ácido chiquímico, principal via de formação de compostos ligados aos mecanismos de defesa das plantas, como: lignina, ácido salicítico e fitoalexinas. Assim, o contato do glyphosate com as folhas do eucalipto pode levar a conseqüências importantes sobre a resistência a doenças. Objetivou-se neste estudo avaliar o envolvimento do glyphosate, via deriva, na severidade da ferrugem causada por Puccinia psidii em genótipos de eucalipto com diferentes níveis de resistência ao patógeno. Para isso, mudas de quatro clones - dois heterozigotos resistentes à ferrugem (UFV01 e UFV02 e dois homozigotos suscetíveis (UFV03 e UFV04 - foram submetidas às subdoses de 0 (testemunha; 28,8; 57,6; 86,4; e 115,2 g ha-1 de glyphosate, simulando deriva. Três dias após a aplicação do glyphosate, as plantas foram inoculadas com o isolado monopustular UFV1 de P. psidii, obtido de Eucalyptus grandis, na região de Itapetininga, SP. Aos 21 dias após a inoculação, foram avaliados a severidade de ferrugem, utilizando-se uma escala diagramática com quatro classes (S0 e S1 resistentes à ferrugem e S2 e S3 suscetíveis, o número de pústulas cm-2 de área foliar, a área foliar lesionada pela ferrugem, o número médio de urediniósporos cm-2 de área foliar, o número médio de urediniósporos/pústula e a porcentagem de intoxicação pelo glyphosate. O clone UFV04 foi o mais sensível ao glyphosate, enquanto o UFV01 apresentou maior tolerância ao herbicida. O glyphosate não alterou o nível de resistência à ferrugem nos genótipos resistentes (UFV01 e UFV02 que apresentaram ausência de pústulas nas folhas, tanto em plantas expostas à deriva quanto nas testemunhas. Para os demais clones, manteve-se a suscetibilidade à ferrugem, embora, com o aumento das doses de glyphosate, tenha se observado diminuição da severidade da doen

  10. Weed species shifts in glyphosate-resistant crops.

    Science.gov (United States)

    Owen, Micheal D K

    2008-04-01

    The adoption of glyphosate-based crop production systems has been one of the most important revolutions in the history of agriculture. Changes in weed communities owing to species that do not respond to current glyphosate-based management tactics are rapidly increasing. Clearly, glyphosate-resistant crops (GRCs) do not influence weeds any more than non-transgenic crops. For most crops, the trait itself is essentially benign in the environment. Rather, the weed control tactics imposed by growers create the ecological selection pressure that ultimately changes the weed communities. This is seen in the adoption of conservation tillage and weed management programs that focus on one herbicide mode of action and have hastened several important weed population shifts. Tillage (disturbance) is one of the primary factors that affect changes in weed communities. The intense selection pressure from herbicide use will result in the evolution of herbicide-resistant weed biotypes or shifts in the relative prominence of one weed species in the weed community. Changes in weed communities are inevitable and an intrinsic consequence of growing crops over time. The glyphosate-based weed management tactics used in GRCs impose the selection pressure that supports weed population shifts. Examples of weed population shifts in GRCs include common waterhemp [Amaranthus tuberculatus (Moq ex DC) JD Sauer], horseweed (Conyza canadensis L), giant ragweed (Ambrosia trifida L) and other relatively new weed problems. Growers have handled these weed population shifts with varying success depending on the crop. PMID:18232055

  11. Efficacy of glyphosate and five surfactants for controlling giant salvinia

    Science.gov (United States)

    Fairchild, J.F.; Allert, A.L.; Riddle, J.S.; Gladwin, D.R.

    2002-01-01

    Giant salvinia (Salvinia molesta Mitchell) is a non-native, invasive aquatic fern that was recently introduced to the southern United States. The aggressive nature of the species has led to concerns over its potential adverse impacts to native plants, fish, and invertebrates. We conducted a study to determine the efficacy of glyphosate [isopropylamine salt of N-(phosphono-methyl)glycine] and several surfactants for control of giant salvinia. Studies were conducted over a 42-day period using static renewals (twice weekly) with 4% Hoagland's medium (10 mg/L N equivalent) in replicated 2-L containers. Five concentrations of glyphosate (0, 0.45, 0.91, 1.82, and 3.60% v:v) and five surfactants (0.25% concentration, v:v; Optima???, Kinetic???, Mon 0818???, Cygnet Plus???, and LI-700???) were applied with a pressurized sprayer as a single surface application in a fully nested experimental design. Untreated giant salvinia grew rapidly and exhibited an increase of 800% wet weight biomass over the 42-day test duration. Glyphosate, with and without surfactants, exhibited efficacy at concentrations as low as 0.45% of the commercial formulation. Glyphosate with Optima was the only mixture that resulted in complete mortality of plants with no regrowth.

  12. Glyphosate resistant weeds - a threat to conservation agriculture

    Science.gov (United States)

    Glyphosate-resistant weeds are now present throughout the Southeast. Hundreds of thousands of conservation tillage cotton acres, some currently under USDA Natural Resources Conservation Service (NRCS) conservation program contracts, are at risk of being converted to higher-intensity tillage systems....

  13. Interactions between glyphosate, Fusarium infection of waterhemp, and soil microorganisms

    Science.gov (United States)

    Greenhouse and laboratory experiments were conducted on waterhemp (Amaranthus rudis Sauer) and soil collected from 144 soybean fields in Missouri that contained late-season waterhemp escapes. The objectives of these experiments were to: 1) determine the frequency and distribution of glyphosate res...

  14. Effect of incorporation of reduced graphene oxide on ZnO-based dye-sensitized solar cells

    Science.gov (United States)

    Song, Jun-Ling; Wang, Xiu

    2016-07-01

    Here, we demonstrate a facile method to improve the cell performance of ZnO-based dye sensitized solar cell by incorporating different amount of reduced graphene oxide (rGO). Overall photo-to-current conversion-efficiency (PCE) of the device 3 with 0.75 mL rGO exhibits a 1.3 times improvement compared to bare ZnO. The electrochemical impedance spectroscopy (EIS) measurements show that the enhancement could be attributed to the improvement of electron transport/injection and the decrease of the charge recombination in the device, which arise from the formation of rGO-based Schottky junction in ZnO-photoanode.

  15. 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

    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...... 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...

  16. Improved Selectivity and Sensitivity of Gas Sensing Using a 3D Reduced Graphene Oxide Hydrogel with an Integrated Microheater.

    Science.gov (United States)

    Wu, Jin; Tao, Kai; Miao, Jianmin; Norford, Leslie K

    2015-12-16

    Low-cost, one-step, and hydrothermal synthesized 3D reduced graphene oxide hydrogel (RGOH) is exploited to fabricate a high performance NO2 and NH3 sensor with an integrated microheater. The sensor can experimentally detect NO2 and NH3 at low concentrations of 200 ppb and 20 ppm, respectively, at room temperature. In addition to accelerating the signal recovery rate by elevating the local silicon substrate temperature, the microheater is exploited for the first time to improve the selectivity of NO2 sensing. Specifically, the sensor response from NH3 can be effectively suppressed by a locally increased temperature, while the sensitivity of detecting NO2 is not significantly affected. This leads to good discrimination between NO2 and NH3. This strategy paves a new avenue to improve the selectivity of gas sensing by using the microheater to raise substrate temperature. PMID:26630364

  17. Fabrication of highly oriented reduced graphene oxide microbelts array for massive production of sensitive ammonia gas sensors

    Science.gov (United States)

    Zhang, Jia; Zhang, Rongfu; Wang, Xiaona; Feng, Wei; Hu, PingAn; O'Neill, William; Wang, Zhenlong

    2013-09-01

    Patterning oriented reduced graphene oxide (rGO) into functional structures is significant for its application in electronics and sensors. A large array of highly oriented rGO microbelts are prepared by a soft lithography process. These rGO microbelts have a uniform structure that enables the massive production of graphene electronics using a simple mask shielding process. A high performance NH3 sensor array which was fabricated from rGO microbelts exhibits a reproducible performance with the relative resistance response (ΔR/R0) reaching 0.35, whilst offering a large concentration range response of 10 ppm ˜38%, showing these sensors to be both highly sensitive and responsive. The impact of working temperature on the response to NH3 in low and high concentration ranges of NH3 is also discussed.

  18. 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.

  19. Development of highly glyphosate-tolerant tobacco by coexpression of glyphosate acetyltransferase gat and EPSPS G2-aroA genes

    Institute of Scientific and Technical Information of China (English)

    Baoqing; Dun; Xujing; Wang; Wei; Lu; Ming; Chen; Wei; Zhang; Shuzhen; Ping; Zhixing; Wang; Baoming; Zhang; Min; Lin

    2014-01-01

    The widely used herbicide glyphosate targets 5-enolpyruvylshikimate-3-phosphate synthase(EPSPS).Glyphosate acetyltransferase(GAT)effectively detoxifies glyphosate by N-acetylation.With the aim of identifying a new strategy for development of glyphosate-tolerant crops,the plant expression vector pG2-GAT harboring gat and G2-aroA(encoding EPSPS)has been transformed into tobacco(Nicotiana tabacum)to develop novel plants with higher tolerance to glyphosate.Results from Southern and Western blotting analyses indicated that the target genes were integrated into tobacco chromosomes and expressed effectively at the protein level.Glyphosate tolerance was compared among transgenic tobacco plants containing gat,G2-aroA,or both genes.Plants containing both gat and G2-aroA genes were the most glyphosate-tolerant.This study has shown that a combination of different strategies may result in higher tolerance in transgenic crops,providing a new approach for development of glyphosate-tolerant crops.

  20. Highly sensitive electrochemical determination of Sunset Yellow based on the ultrafine Au-Pd and reduced graphene oxide nanocomposites.

    Science.gov (United States)

    Wang, Jin; Yang, Beibei; Zhang, Ke; Bin, Duan; Shiraishi, Yukihide; Yang, Ping; Du, Yukou

    2016-11-01

    A sensitive and novel electrochemical sensor with Au-Pd and reduced graphene oxide (RGO) nanocomposites modified glassy carbon electrode (Au-Pd-RGO/GCE) was successfully fabricated by one-step synthesis method for the detection of Sunset Yellow. The as-prepared composites were uniformly dispersed on the surface of electrode with an average diameter of approximately 3.44nm, and the ultrafine nanoparticles effectively enhanced the electrochemical active surface area of GCE. The modified electrode had been characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and electrochemical tests. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) results showed high stability and outstanding electrocatalytic activity of Au-Pd-RGO/GCE for the detection of SY with low detection limits (1.5 nM, S/N=3) and wide concentration ranges (0.686-331.686μM). The Au-Pd-RGO/GCE was further applied to detect SY in real samples with good recovery. Herein, the fabricated Au-Pd-RGO/GCE showed excellent sensitivity, stability and repeatability for the detection of SY and will be a promising application in electrochemical sensor. PMID:27475710

  1. Highly sensitive nonenzymatic glucose sensor based on nickel nanoparticle-attapulgite-reduced graphene oxide-modified glassy carbon electrode.

    Science.gov (United States)

    Shen, Zongxu; Gao, Wenyu; Li, Pei; Wang, Xiaofang; Zheng, Qing; Wu, Hao; Ma, Yuehui; Guan, Weijun; Wu, Songmei; Yu, Yu; Ding, Kejian

    2016-10-01

    In this article, a fast and sensitive nonenzymatic glucose sensor is reported utilizing a glassy carbon electrode modified by synthesizing nanocomposites of nickel nanoparticle-attapulgite-reduced graphene oxide (Ni NPs/ATP/RGO). A facile one-step electrochemical co-deposition approach is adopted to synthesize Ni NPs-ATP-RGO nanocomposites via electrochemical reduction of mixed precursor solution containing graphene oxide (GO), attapulgite (ATP) and nickel cations (Ni(2+)) at the cathode potentials. This strategy results in simultaneous depositions of ATP, cathodic reduction of Ni(2+) into nickel nanoparticles under acidic conditions, and in situ reduction of GO. The as-prepared NiNPs/ATP/RGO-based glucose sensor exhibits outstanding performance for enzymeless glucose sensing with sensitivity (1414.4 μAmM(-1)cm(-2)), linear range (1-710μM) and detection limit (0.37μM). What is more, the sensor has excellent stability and selectivity against common interferences in real sample. PMID:27474298

  2. Reducing Production Basis Risk through Rainfall Intensity Frequency (RIF) Indexes: Global Sensitivity Analysis' Implication on Policy Design

    Science.gov (United States)

    Muneepeerakul, Chitsomanus; Huffaker, Ray; Munoz-Carpena, Rafael

    2016-04-01

    The weather index insurance promises financial resilience to farmers struck by harsh weather conditions with swift compensation at affordable premium thanks to its minimal adverse selection and moral hazard. Despite these advantages, the very nature of indexing causes the presence of "production basis risk" that the selected weather indexes and their thresholds do not correspond to actual damages. To reduce basis risk without additional data collection cost, we propose the use of rain intensity and frequency as indexes as it could offer better protection at the lower premium by avoiding basis risk-strike trade-off inherent in the total rainfall index. We present empirical evidences and modeling results that even under the similar cumulative rainfall and temperature environment, yield can significantly differ especially for drought sensitive crops. We further show that deriving the trigger level and payoff function from regression between historical yield and total rainfall data may pose significant basis risk owing to their non-unique relationship in the insured range of rainfall. Lastly, we discuss the design of index insurance in terms of contract specifications based on the results from global sensitivity analysis.

  3. Evidence of heterosynaptic LTD in the human nociceptive system: superficial skin neuromodulation using a matrix electrode reduces deep pain sensitivity.

    Directory of Open Access Journals (Sweden)

    Martin Mücke

    Full Text Available Long term depression (LTD is a neuronal learning mechanism after low frequency stimulation (LFS. This study compares two types of electrodes (concentric vs. matrix and stimulation frequencies (4 and 30 Hz to examine homo- and heterosynaptic effects indirectly depicted from the somatosensory profile of healthy subjects. Both electrodes were compared in a prospective, randomized, controlled cross-over study using 4 Hz as the conditioning LFS compared to 30 Hz (intended sham condition. Quantitative sensory testing (QST was used to examine 13 thermal and mechanical detection and pain thresholds. Sixteen healthy volunteers (10 women, age 31.0 ± 12.7 years were examined. Depending on the electrodes and frequencies used a divergent pattern of sensory minus signs occurred. Using LFS the concentric electrode increased thermal thresholds, while the matrix electrode rather increased mechanical including deep pain thresholds. Findings after cutaneous neuromodulation using LFS and a matrix electrode are consistent with the concept of heterosynaptic LTD in the human nociceptive system, where deep pain sensitivity was reduced after superficial stimulation of intraepidermal nerve fibres. Cutaneous neuromodulation using LFS and a matrix electrode may be a useful tool to influence deep pain sensitivity in a variety of chronic pain syndromes.

  4. Glyphosate, other herbicides, and transformation products in Midwestern streams, 2002

    Science.gov (United States)

    Battaglin, W.A.; Kolpin, D.W.; Scribner, E.A.; Kuivila, K.M.; Sandstrom, M.W.

    2005-01-01

    The use of glyphosate has increased rapidly, and there is limited understanding of its environmental fate. The objective of this study was to document the occurrence of glyphosate and the transformation product aminomethylphosphonic acid (AMPA) in Midwestern streams and to compare their occurrence with that of more commonly measured herbicides such as acetochlor, atrazine, and metolachlor. Water samples were collected at sites on 51 streams in nine Midwestern states in 2002 during three runoff events: after the application of pre-emergence herbicides, after the application of post-emergence herbicides, and during harvest season. All samples were analyzed for glyphosate and 20 other herbicides using gas chromatography/mass spectrometry or high performance liquid chromatography/mass spectrometry. The frequency of glyphosate and AMPA detection, range of concentrations in runoff samples, and ratios of AMPA to glyphosate concentrations did not vary throughout the growing season as substantially as for other herbicides like atrazine, probably because of different seasonal use patterns. Glyphosate was detected at or above 0.1 μg/1 in 35 percent of pre-emergence, 40 percent of post-emergence, and 31 percent of harvest season samples, with a maximum concentration of 8.7 μg/1. AMPA was detected at or above 0.1 μg/1 in 53 percent of pre-emergence, 83 percent of post-emergence, and 73 percent of harvest season samples, with a maximum concentration of 3.6 μg/1. Glyphosate was not detected at a concentration at or above the U.S. Environmental Protection Agency's maximum contamination level (MCL) of 700 μg/1 in any sample. Atrazine was detected at or above 0.1 μg/1 in 94 percent of pre-emergence, 96 percent of post-emergence, and 57 percent of harvest season samples, with a maximum concentration of 55 μg/1. Atrazine was detected at or above its MCL (3 μg/1) in 57 percent of pre-emergence and 33 percent of post-emergence samples

  5. Dexamethasone reduces sensitivity to cisplatin by blunting p53-dependent cellular senescence in non-small cell lung cancer.

    Directory of Open Access Journals (Sweden)

    Haiyan Ge

    Full Text Available INTRODUCTION: Dexamethasone (DEX co-treatment has proved beneficial in NSCLC patients, improving clinical symptoms by the reduction of side effects after chemotherapy. However, recent studies have shown that DEX could render cancer cells more insensitive to cytotoxic drug therapy, but it is not known whether DEX co-treatment could influence therapy-induced senescence (TIS, and unknown whether it is in a p53-dependent or p53-independent manner. METHODS: We examined in different human NSCLC cell lines and detected cellular senescence after cisplatin (DDP treatment in the presence or absence of DEX. The in vivo effect of the combination of DEX and DDP was assessed by tumor growth experiments using human lung cancer cell lines growing as xenograft tumors in nude mice. RESULTS: Co-treatment with DEX during chemotherapy in NSCLC resulted in increased tumor cell viability and inhibition of TIS compared with DDP treated group. DEX co-treatment cells exhibited the decrease of DNA damage signaling pathway proteins, the lower expression of p53 and p21(CIP1, the lower cellular secretory program and down-regulation of NF-κB and its signaling cascade. DEX also significantly reduced DDP sensitivity in vivo. CONCLUSIONS: Our results underscore that DEX reduces chemotherapy sensitivity by blunting therapy induced cellular senescence after chemotherapy in NSCLC, which may, at least in part, in a p53-dependent manner. These data therefore raise concerns about the widespread combined use of gluocorticoids (GCs with antineoplastic drugs in the clinical management of cancer patients.

  6. l-Isocorypalmine reduces behavioral sensitization and rewarding effects of cocaine in mice by acting on dopamine receptors*

    Science.gov (United States)

    Xu, Wei; Wang, Yujun; Ma, Zhongze; Chiu, Yi-Ting; Huang, Peng; Rasakham, Khampaseuth; Unterwald, Ellen; Lee, David Y.-W.; Liu-Chen, Lee-Yuan

    2013-01-01

    Background We previously reported isolation of l-isocorypalmine (l-ICP), a mono-demethylated analog of l-tetrahydropalmatine (l-THP), from the plant Corydalis yanhusuo. Here we characterized its in vitro pharmacological properties and examined its effects on cocaine-induced behaviors in mice. Methods Receptor binding, cAMP and [35S]GTPγS assays were used to examine pharmacological actions of l-ICP in vitro. Effects of I-ICP on cocaine-induced locomotor hyperactivity and sensitization and conditioned place preference (CPP) in mice were investigated. HPLC was employed to analyze metabolites of I-ICP in mouse serum. Results Among more than 40 targets screened, l-ICP and l-THP bound only to dopamine (DA) receptors. l-ICP was a high-affinity partial agonist of D1 and D5 receptors and a moderate-affinity antagonist of D2, D3 and D4 receptors, whereas l-THP bound to only D1 and D5 receptors, with lower affinities than l-ICP. At 10 mg/kg (i.p.), l-ICP inhibited spontaneous locomotor activity for a shorter time than l-THP. Pretreatment with l-ICP reduced cocaine-induced locomotor hyperactivities. Administration of l-ICP before cocaine once a day for 5 days reduced cocaine-induced locomotor sensitization on days 5 and 13 after 7 days of withdrawal. Pretreatment with l-ICP before cocaine daily for 6 days blocked cocaine-induced CPP, while l-ICP itself did not cause preference or aversion. HPLC analysis showed that l-ICP was the main compound in mouse serum following i.p. injection of l-ICP. Conclusions l-ICP likely acts as a D1 partial agonist and a D2 antagonist to produce its in vivo effects and may be a promising agent for treatment of cocaine addiction. PMID:24080315

  7. 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

  8. 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)

  9. 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.

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

    Directory of Open Access Journals (Sweden)

    Marcos Altomani Neves Dias

    2015-09-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Marcos Altomani Neves Dias

    2015-01-01

    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.

  12. The effect of glyphosate on potential pathogens and beneficial members of poultry microbiota in vitro.

    Science.gov (United States)

    Shehata, Awad A; Schrödl, Wieland; Aldin, Alaa A; Hafez, Hafez M; Krüger, Monika

    2013-04-01

    The use of glyphosate modifies the environment which stresses the living microorganisms. The aim of the present study was to determine the real impact of glyphosate on potential pathogens and beneficial members of poultry microbiota in vitro. The presented results evidence that the highly pathogenic bacteria as Salmonella Entritidis, Salmonella Gallinarum, Salmonella Typhimurium, Clostridium perfringens and Clostridium botulinum are highly resistant to glyphosate. However, most of beneficial bacteria as Enterococcus faecalis, Enterococcus faecium, Bacillus badius, Bifidobacterium adolescentis and Lactobacillus spp. were found to be moderate to highly susceptible. Also Campylobacter spp. were found to be susceptible to glyphosate. A reduction of beneficial bacteria in the gastrointestinal tract microbiota by ingestion of glyphosate could disturb the normal gut bacterial community. Also, the toxicity of glyphosate to the most prevalent Enterococcus spp. could be a significant predisposing factor that is associated with the increase in C. botulinum-mediated diseases by suppressing the antagonistic effect of these bacteria on clostridia.

  13. 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 π electron rich biochar surface via π-π 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.

  14. 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.

  15. 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

  16. 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.

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

    OpenAIRE

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

    2015-01-01

    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. T...

  18. Growth stage influences level of resistance in glyphosate-resistant horseweed

    OpenAIRE

    Shrestha, Anil; Hembree, Kurt J; Va, Neil

    2007-01-01

    While glyphosate-resistant horseweed has not previously been reported in California, we suspected that it might exist, especially in noncrop areas. We collected horseweed seeds from two locations in the San Joaquin Valley and treated greenhouse-grown plants at different stages with different amounts of glyphosate. This study showed that a glyphosate-resistant biotype of horseweed exists in the noncrop areas of Dinuba, in Tulare County, and that the level of resistance may be influenced by the...

  19. Review of GMO safety assessment studies: glyphosate residues in Roundup Ready crops is an ignored issue

    OpenAIRE

    Cuhra, Marek

    2015-01-01

    Published version, also available at http://dx.doi.org/10.1186/s12302-015-0052-7 Background Genetically modified glyphosate-tolerant cultivar varieties have been a commercial success widely known as Roundup Ready plants. As new glyphosate-tolerant varieties are introduced to satisfy agriculture demand, it is relevant to review the scientific evidence that documents the quality and safety of such biotechnology. Assessments of genetically modified glyphosate-tolerant plants are partly ba...

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

    OpenAIRE

    Changpeng Zhang; Xiuqing Hu; Jinyan Luo; Zhiyi Wu; Li Wang; Bin Li,; Yanli Wang; Guochang Sun

    2015-01-01

    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...

  1. Uses of glyphosate in German arable farming – aspects of weed management and arable practice

    OpenAIRE

    Wiese, Armin; Schulte, Michael; Theuvsen, Ludwig

    2016-01-01

    Data on glyphosate use, personal attitudes and farm characteristics were collected in a Germany-wide inventory from 2026 farms. About 1700 farms could be analyzed in detail. Categories of glyphosate users were split into: non-users, low proportion users and high proportion users. The latter apply glyphosate on > 20% of their arable land are characterized by a high amount of non-inversion tillage, low labor effort and aboveaverage farm size. Perennial weeds play a less important role for glyph...

  2. 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...

  3. Annual Glyphosate Treatments Alter Growth of Unaffected Bentgrass (Agrostis) Weeds and Plant Community Composition

    OpenAIRE

    Ahrens, Collin W.; Carol A Auer

    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 ...

  4. Losses of glyphosate and AMPA via drainflow in a typical Belgian residential area

    Science.gov (United States)

    Tang, Ting; Boënne, Wesley; van Griensven, Ann; Seuntjens, Piet; Bronders, Jan; Desmet, Nele

    2014-05-01

    Urban hard surfaces are considered as important facilitators for pesticide transport into urban streams. To obtain concurrent high-resolution data for a detailed investigation on the losses of pesticide runoff from hard surfaces, a monitoring campaign was performed in a typical Belgian residential area (9.5 ha) between 7 May and 7 August, 2013. The campaign yielded a concurrent dataset of rainfall (1-mm rainfall interval), discharge (1-min interval), glyphosate application by the residents and the occurrences of glyphosate and its major degradation product - aminomethylphosphonic acid (AMPA) in the separated storm drainage outflow during 12 rainfall events. In addition, detailed information was obtained on the spatial characteristics of the study area. The resulting dataset allows us to investigate the relevance of catchment hydrology, urban surface properties and pesticide application to the transport and losses of glyphosate in a residential environment. During the campaign, glyphosate was only applied by local residents, mainly on their private driveways. As a result of their continuous use, both glyphosate and AMPA were detected in all analysed outflow samples, with maximum concentrations of 6.1 μg/L and 5.8 μg/L, respectively. Overall, the storm drainage system collected 0.43% of the applied amount of glyphosate. However, this loss rate varied considerably among rainfall events, ranging from 0.04% to 23.36%. According to statistical analysis of the 12 rainfall events, the loss rate was significantly correlated with three factors: the application amount prior to a rainfall event (p glyphosate application and the start of the rainfall event (negatively, p glyphosate. Furthermore, three types of glyphosate runoff were classified by a clustering analysis based on these factors: events dominated by runoff availability (runoff-limited), dominated by glyphosate availability (pesticide-limited) and controlled by both runoff and glyphosate availability. To sum up

  5. 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...

  6. Alteração das características biológicas dos biótipos de azevém (Lolium multiflorum ocasionada pela resistência ao herbicida glyphosate Change in the biological characteristics of ryegrass (Lolium multiflorum biotypes caused by resistance to the herbicide glyphosate

    Directory of Open Access Journals (Sweden)

    L. Vargas

    2005-03-01

    accumulation by the biotype were assessed. In the second experiment different rates of glyphosate and grass herbicides were tested: glyphosate, haloxyfop-r, diclofop, fluazifop-p, fenoxaprop-p and paraquat. A third experiments was carried out under glasshouse conditions to determine the curve of dry matter accumulation. The results showed GR50 of 287.5 and 4,833.5 g e. a. ha-1 of glyphosate for the sensitive and resistant biotypes, respectively. The results showed that the resistant factor (RF was 16.8 and that the resistance mechanism alters the biological characteristics of the resistant biotype affecting its sensitivity to grass herbicides.

  7. Establishment of PCR-ELISA for Detecting Glyphosate Resistant Transgenic Soybean

    Institute of Scientific and Technical Information of China (English)

    Yuan Qiang; Wei Yun-min; Fu Ming-ming; Qiu You-wen; Wen Hong-tao; Zhang Ming-hui; Liu Ying; Ao Jin-xia

    2016-01-01

    A PCR-ELISA method for detecting the glyphosate resistant transgenic soybean was established and optimized. The results showed that the key parameters of PCR-ELISA were as follows: the concentration of digoxin tag probe was 0.5 μmol• L-1, the time of hybridization reaction was 15 min and the chromogenic reaction should last for 30 min. The sensitivity and the repeatability of our PCR-ELISA method were evaluated, and the results showed that it could be detected when the concentration of DNA template from transgenic soybean samples was 0.01% or higher, and the coefficient of variation of this method was less than 5% in our research condition. These results suggested that PCR-ELISA method establishment in this study had good repeatability and high precision for detecting the transgenic soybean samples.

  8. Thrombospondin1 deficiency reduces obesity-associated inflammation and improves insulin sensitivity in a diet-induced obese mouse model.

    Directory of Open Access Journals (Sweden)

    Yanzhang Li

    Full Text Available BACKGROUND: Obesity is prevalent worldwide and is associated with insulin resistance. Advanced studies suggest that obesity-associated low-grade chronic inflammation contributes to the development of insulin resistance and other metabolic complications. Thrombospondin 1 (TSP1 is a multifunctional extracellular matrix protein that is up-regulated in inflamed adipose tissue. A recent study suggests a positive correlation of TSP1 with obesity, adipose inflammation, and insulin resistance. However, the direct effect of TSP1 on obesity and insulin resistance is not known. Therefore, we investigated the role of TSP1 in mediating obesity-associated inflammation and insulin resistance by using TSP1 knockout mice. METHODOLOGY/PRINCIPAL FINDINGS: Male TSP1-/- mice and wild type littermate controls were fed a low-fat (LF or a high-fat (HF diet for 16 weeks. Throughout the study, body weight and fat mass increased similarly between the TSP1-/- mice and WT mice under HF feeding conditions, suggesting that TSP1 deficiency does not affect the development of obesity. However, obese TSP1-/- mice had improved glucose tolerance and increased insulin sensitivity compared to the obese wild type mice. Macrophage accumulation and inflammatory cytokine expression in adipose tissue were reduced in obese TSP1-/- mice. Consistent with the local decrease in pro-inflammatory cytokine levels, systemic inflammation was also decreased in the obese TSP1-/- mice. Furthermore, in vitro data demonstrated that TSP1 deficient macrophages had decreased mobility and a reduced inflammatory phenotype. CONCLUSION: TSP1 deficiency did not affect the development of high-fat diet induced obesity. However, TSP1 deficiency reduced macrophage accumulation in adipose tissue and protected against obesity related inflammation and insulin resistance. Our data demonstrate that TSP1 may play an important role in regulating macrophage function and mediating obesity-induced inflammation and insulin

  9. Reduced sensitivity to both positive and negative reinforcement in mice over-expressing the 5-hydroxytryptamine transporter.

    Science.gov (United States)

    Line, Samantha J; Barkus, Chris; Rawlings, Nancy; Jennings, Katie; McHugh, Stephen; Sharp, Trevor; Bannerman, David M

    2014-12-01

    The 5-hydroxytryptamine (5-HT) transporter (5-HTT) is believed to play a key role in both normal and pathological psychological states. Much previous data suggest that the s allele of the polymorphic regulatory region of the 5-HTT gene promoter is associated with reduced 5-HTT expression and vulnerability to psychiatric disorders, including anxiety and depression. In comparison, the l allele, which increases 5-HTT expression, is generally considered protective. However, recent data link this allele to both abnormal 5-HT signalling and psychopathic traits. Here, we studied the processing of aversive and rewarding cues in transgenic mice that over-express the 5-HTT (5-HTTOE mice). Compared with wild-type mice, 5-HTTOE mice froze less in response to both a tone that had previously been paired with footshock, and the conditioning context. In addition, on a decision-making T-maze task, 5-HTTOE mice displayed reduced preference for a larger, delayed reward and increased preference for a smaller, immediate reward, suggesting increased impulsiveness compared with wild-type mice. However, further inspection of the data revealed that 5-HTTOE mice displayed a relative insensitivity to reward magnitude, irrespective of delay. In contrast, 5-HTTOE mice appeared normal on tests of spatial working and reference memory, which required an absolute choice between options associated with either reward or no reward. Overall, the present findings suggest that 5-HTT over-expression results in a reduced sensitivity to both positive and negative reinforcers. Thus, these data show that increased 5-HTT expression has some maladaptive effects, supporting recent suggestions that l allele homozygosity may be a potential risk factor for disabling psychiatric traits.

  10. Tolerance of Glyphosate-Resistant Maize to Glyphosate Plus MCPA Amine Is Influenced by Dose and Timing

    Directory of Open Access Journals (Sweden)

    Nader Soltani

    2015-01-01

    Full Text Available There is little information on tolerance of glyphosate-resistant maize to glyphosate plus MCPA amine as influenced by dose and timing under Ontario environmental conditions. A total of seven field trials were conducted at various locations in Ontario, Canada, in 2011–2013 to evaluate tolerance of field maize to tank mixes of glyphosate (900 g a.e./ha plus MCPA amine (79, 158, 315, 630, 1260, 2520, or 5040 g a.e./ha at either the 4- or 8-leaf stage. The predicted dose of MCPA amine that caused 5, 10, and 20% injury was 339, 751, and 1914 g a.e./ha when applied to 4-leaf maize but only 64, 140, and 344 g a.e./ha when applied to 8-leaf maize, respectively. The predicted dose of MCPA amine that caused 5, 10, and 20% reduction in shoot dry weight of maize was 488, 844, and 1971 g a.e./ha when applied to 4-leaf maize and only 14, 136, and 616 g a.e./ha when applied to 8-leaf maize, respectively. The predicted dose of MCPA amine that caused 5, 10, and 20% yield reduction was 2557, 4247, and >5040 g a.e./ha when applied to 4-leaf maize and 184, 441, and 1245 g a.e./ha when applied to 8-leaf maize, respectively. Based on these results, glyphosate plus MCPA amine applied at the manufacturer’s recommended dose of 630 g a.e./ha applied to 4-leaf maize has potential to cause injury but the injury is transient with no significant reduction in yield. However, when glyphosate plus MCPA amine is applied to 8-leaf maize it has the potential to cause significant injury and yield loss in maize.

  11. 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.

  12. Glyphosate Utilization as the Source of Carbon: Isolation and Identification of new Bacteria

    Directory of Open Access Journals (Sweden)

    M. Mohsen Nourouzi

    2011-01-01

    Full Text Available Mixed bacteria from oil palm plantation soil (OPS were isolated to investigate their ability to utilize glyphosate as carbon source. Results showed that approximately all of the glyphosate was converted to aminomethyl-phosphonic acid (AMPA (99.5%. It is worthy to note that mixed bacteria were able to degrade only 2% of AMPA to further metabolites. Two bacterial strains i.e. Stenotrophomonas maltophilia and Providencia alcalifaciens were obtained from enrichment culture. Bacterial isolates were cultured individually on glyphosate as a sole carbon source. It was observed that both isolates were able to convert glyphosate to AMPA.

  13. Effects of glyphosate on soil microbial communities and its mineralization in a Mississippi soil.

    Science.gov (United States)

    Weaver, Mark A; Krutz, L Jason; Zablotowicz, Robert M; Reddy, Krishna N

    2007-04-01

    Transgenic glyphosate-resistant (GR) soybean [Glycine max (L.) Merr.] has enabled highly effective and economical weed control. The concomitant increased application of glyphosate could lead to shifts in the soil microbial community. The objective of these experiments was to evaluate the effects of glyphosate on soil microbial community structure, function and activity. Field assessments on soil microbial communities were conducted on a silt loam soil near Stoneville, MS, USA. Surface soil was collected at time of planting, before initial glyphosate application and 14 days after two post-emergence glyphosate applications. Microbial community fatty acid methyl esters (FAMEs) were analyzed from these soil samples and soybean rhizospheres. Principal component analysis of the total FAME profile revealed no differentiation between field treatments, although the relative abundance of several individual fatty acids differed significantly. There was no significant herbicide effect in bulk soil or rhizosphere soils. Collectively, these findings indicate that glyphosate caused no meaningful whole microbial community shifts in this time period, even when applied at greater than label rates. Laboratory experiments, including up to threefold label rates of glyphosate, resulted in up to a 19% reduction in soil hydrolytic activity and small, brief (glyphosate was mineralized when applied at threefold field rates, with about 9% forming bound residues. These results indicate that glyphosate has only small and transient effects on the soil microbial community, even when applied at greater than field rates.

  14. Glyphosate inhibition of ferric reductase activity in iron deficient sunflower roots

    OpenAIRE

    Öztürk, Levent; Ozturk, Levent; Yazıcı, Mustafa Atilla; Yazici, Mustafa Atilla; Eker, Selim; Gökmen, Özay Özgür; Gokmen, Ozay Ozgur; Römheld, Volker; Romheld, Volker; ÇAKMAK, İsmail; Cakmak, Ismail

    2007-01-01

    Iron (Fe) deficiency is increasingly being observed in cropping systems with frequent glyphosate applications. A likely reason for this is that glyphosate interferes with root uptake of Fe by inhibiting ferric reductase in roots required for Fe acquisition by dicot and nongrass species. This study investigated the role of drift rates of glyphosate (0.32, 0.95 or 1.89 mM glyphosate corresponding to 1, 3 and 6% of the recommended herbicidal dose, respectively) on ferric reductase activity of...

  15. 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...

  16. 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 μm 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...

  17. Inheritance of Evolved Glyphosate Resistance in a North Carolina Palmer Amaranth (Amaranthus palmeri) Biotype

    OpenAIRE

    Aman Chandi; Susana R. Milla-Lewis; Darci Giacomini; Philip Westra; Christopher Preston; Jordan, David L.; Alan C. York; James D. Burton; Jared R. Whitaker

    2012-01-01

    Inheritance of glyphosate resistance in a Palmer amaranth biotype from North Carolina was studied. Glyphosate rates for 50% survival of glyphosate-resistant (GR) and glyphosate-susceptible (GS) biotypes were 1288 and 58 g ha−1, respectively. These values for F1 progenies obtained from reciprocal crosses (GR×GS and GS×GR were 794 and 501 g ha−1, respectively. Dose response of F1 progenies indicated that resistance was not fully dominant over susceptibility. Lack of significant differences betw...

  18. The Research Progress of Glyphosate Resistance%草甘膦抗性研究进展

    Institute of Scientific and Technical Information of China (English)

    武骁

    2014-01-01

    草甘膦抗性研究集中在2个方面:抗草甘膦作物的研究、杂草对草甘膦抗性的研究。结合草甘膦的开发与发展,论述了这2种抗性的发展及相关研究。%Glyphosate resistance study concentrated on two aspects: glyphosate-tolerant crop, resistance weeds to glyphosate. Combined with the development and evolution of glyphosate, the development and related research of these resistances discusses in this paper.

  19. Growth and Reproduction of Glyphosate-Resistant and Susceptible Populations of Kochia scoparia

    OpenAIRE

    Vipan Kumar; Prashant Jha

    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-sus...

  20. Direct determination of glyphosate and its major metabolite, aminomethylphosphonic acid, in fruits and vegetables by mixed-mode hydrophilic interaction/weak anion-exchange liquid chromatography coupled with electrospray tandem mass spectrometry.

    Science.gov (United States)

    Chen, Ming-Xue; Cao, Zhao-Yun; Jiang, Yan; Zhu, Zhi-Wei

    2013-01-11

    A novel method was developed for the direct, sensitive, and rapid determination of glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), in fruit and vegetable samples by mixed-mode hydrophilic interaction/weak anion-exchange liquid chromatography (HILIC/WAX) coupled with electrospray tandem mass spectrometry (ESI-MS/MS). Homogenized samples were extracted with water, without derivatization or further clean-up, and the extracts were injected directly onto the Asahipak NH2P-50 4E column (250 mm × 4.6 mm i.d., 5 μm). The best results were obtained when the column was operated under mixed-mode HILIC/WAX elution conditions. An initial 10-min washing step with acetonitrile/water (10:90, v/v) in HILIC mode was used to remove potentially interfering compounds, and then the analytes were eluted in WAX mode with acetonitrile and water containing 0.1 molL(-1) ammonium hydroxide under gradient elution for the ESI analysis in negative ion mode. Limits of quantification of glyphosate and AMPA were 5 μgkg(-1) and 50 μgkg(-1), respectively, with limits of detection as low as 1.2 μgkg(-1) for glyphosate and 15 μgkg(-1) for AMPA. The linearity was satisfactory, with correlation coefficients (r)>0.9966. Recovery studies were carried out on spiked matrices (6 vegetables, 3 fruits) with glyphosate at four concentrations and AMPA at three concentrations. The mean recoveries for glyphosate and AMPA were 75.3-110% and 76.1-110%, respectively, with relative standard deviations in the range of 1.1-13.8%. The intra-day precision (n=7) for glyphosate and AMPA in vegetable and fruit samples spiked at an intermediate level between 5.9% and 7.5%, and the inter-day precision over 11 days (n=11) was between 7.0% and 13%.

  1. 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.

  2. 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 De 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...

  3. 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...

  4. Glutamate Cysteine Ligase—Modulatory Subunit Knockout Mouse Shows Normal Insulin Sensitivity but Reduced Liver Glycogen Storage

    KAUST Repository

    Lavoie, Suzie

    2016-04-21

    Glutathione (GSH) deficits have been observed in several mental or degenerative illness, and so has the metabolic syndrome. The impact of a decreased glucose metabolism on the GSH system is well-known, but the effect of decreased GSH levels on the energy metabolism is unclear. The aim of the present study was to investigate the sensitivity to insulin in the mouse knockout (KO) for the modulatory subunit of the glutamate cysteine ligase (GCLM), the rate-limiting enzyme of GSH synthesis. Compared to wildtype (WT) mice, GCLM-KO mice presented with reduced basal plasma glucose and insulin levels. During an insulin tolerance test, GCLM-KO mice showed a normal fall in glycemia, indicating normal insulin secretion. However, during the recovery phase, plasma glucose levels remained lower for longer in KO mice despite normal plasma glucagon levels. This is consistent with a normal counterregulatory hormonal response but impaired mobilization of glucose from endogenous stores. Following a resident-intruder stress, during which stress hormones mobilize glucose from hepatic glycogen stores, KO mice showed a lower hyperglycemic level despite higher plasma cortisol levels when compared to WT mice. The lower hepatic glycogen levels observed in GCLM-KO mice could explain the impaired glycogen mobilization following induced hypoglycemia. Altogether, our results indicate that reduced liver glycogen availability, as observed in GCLM-KO mice, could be at the origin of their lower basal and challenged glycemia. Further studies will be necessary to understand how a GSH deficit, typically observed in GCLM-KO mice, leads to a deficit in liver glycogen storage.

  5. 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

  6. Controllable Electrochemical Synthesis of Reduced Graphene Oxide Thin-Film Constructed as Efficient Photoanode in Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Soon Weng Chong

    2016-01-01

    Full Text Available A controllable electrochemical synthesis to convert reduced graphene oxide (rGO from graphite flakes was introduced and investigated in detail. Electrochemical reduction was used to prepare rGO because of its cost effectiveness, environmental friendliness, and ability to produce rGO thin films in industrial scale. This study aimed to determine the optimum applied potential for the electrochemical reduction. An applied voltage of 15 V successfully formed a uniformly coated rGO thin film, which significantly promoted effective electron transfer within dye-sensitized solar cells (DSSCs. Thus, DSSC performance improved. However, rGO thin films formed in voltages below or exceeding 15 V resulted in poor DSSC performance. This behavior was due to poor electron transfer within the rGO thin films caused by poor uniformity. These results revealed that DSSC constructed using 15 V rGO thin film exhibited high efficiency (η = 1.5211% attributed to its higher surface uniformity than other samples. The addition of natural lemon juice (pH ~ 2.3 to the electrolyte accelerated the deposition and strengthened the adhesion of rGO thin film onto fluorine-doped tin oxide (FTO glasses.

  7. Reducing the risk of sensitivity and pulpal complications after the placement of crowns and fixed partial dentures.

    Science.gov (United States)

    Brännström, M

    1996-10-01

    Sensitivity after cementation of a crown with glass-ionomer cement is often attributed to an adverse effect on the pulp by the luting agent. Most permanent restorative materials in common use today do not tend to irritate the pulp; the main cause of pulpal damage is infection, the bacteria originating in the smear layer or deep in the dental tubules, inaccessible to caries-excavating procedures. A poorly fitting provisional crown may expose cut dentin to the oral fluids, and mechanical trauma caused by frictional heat during preparation may also damage the pulp. The following precautions are recommended during precementation procedures to reduce the risk of an inflammatory response in the pulp: (1) The provisional crown should be well fitting, covering cervical dentin but not impinging on the periodontal tissues. The permanent crown should be cemented as soon as possible. (2) The superficial smear layer should be removed and the dentinal surface should be treated with an antibacterial solution before the provisional crown is placed. (3) To decrease dentinal permeability under the provisional crown, the dentinal surface should be covered with a liner that can be easily removed before final cementation. (4) to ensure optimal mircomechanical bonding, the dentinal surface should be thoroughly cleaned, and the dentin should be kept moist until cementation. (5) The occlusion should be carefully checked before cementation of the crown. PMID:9180403

  8. Electrocatalytic oxidation of nitrite using metal-free nitrogen-doped reduced graphene oxide nanosheets for sensitive detection.

    Science.gov (United States)

    Chen, Dong; Jiang, Jingjing; Du, Xuezhong

    2016-08-01

    Nitrite can become poisonous to animals and human beings as it can lead to generation of carcinogenic N-nitrosamines. Metal-free nitrogen-doped reduced graphene oxide (NrGO) exhibited a good electrocatalytic activity toward oxidation of nitrite with the relatively low oxidation potential of 0.68V (v.s. saturated calomel electrode), thus, a facile electrochemical sensor based on metal-free NrGO was fabricated for sensitive detection of nitrite for the first time. The novel sensor showed a wide linear concentration range from 0.5 to 5000μM and a low detection limit of 0.2μM at the signal-to-noise ratio of 3 with good selectivity, stability, and reproducibility. This fabricated sensor was used for the determination of nitrite in pickled garlic and river water. These results demonstrate that the facile metal-free NrGO-modified electrochemical sensor has promising applications for the determination of nitrite in food and environment. PMID:27216690

  9. 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.

  10. Trefoil factor 3 (TFF3) enhances the oncogenic characteristics of prostate carcinoma cells and reduces sensitivity to ionising radiation.

    Science.gov (United States)

    Perera, Omesha; Evans, Angharad; Pertziger, Mikhail; MacDonald, Christa; Chen, Helen; Liu, Dong-Xu; Lobie, Peter E; Perry, Jo K

    2015-05-28

    Trefoil factor 3 (TFF3) is a secreted protein which functions in mucosal repair of the gastrointestinal tract. This is achieved through the combined stimulation of cell migration and prevention of apoptosis and anoikis, thus facilitating repair. Deregulated TFF3 expression at the gene and protein level is implicated in numerous cancers. In prostate cancer TFF3 has previously been reported as a potential biomarker, overexpressed in a subset of primary and metastatic cases. Here we investigated the effect of increased TFF3 expression on prostate cancer cell behaviour. Oncomine analysis demonstrated that TFF3 mRNA expression was upregulated in prostate cancer compared to normal tissue. Forced-expression models were established in the prostate cancer cell lines, DU145 and PC3, by stable transfection of an expression vector containing the TFF3 cDNA. Forced expression of TFF3 significantly increased total cell number and cell viability, cell proliferation and cell survival. In addition, TFF3 enhanced anchorage independent growth, 3-dimensional colony formation, wound healing and cell migration compared to control transfected cell lines. We also observed reduced sensitivity to ionising radiation in stably transfected cell lines. In dose response experiments, forced expression of TFF3 significantly enhanced the regrowth of PC3 cells following ionising radiation compared with control transfected cells. In addition, TFF3 enhanced clonogenic survival of DU145 and PC3 cells. These studies indicate that targeting TFF3 for the treatment of prostate cancer warrants further investigation.

  11. Decrease of back recombination rate in CdS quantum dots sensitized solar cells using reduced graphene oxide

    Institute of Scientific and Technical Information of China (English)

    Ali Badawi

    2015-01-01

    The photovoltaic performance of CdS quantum dots sensitized solar cells (QDSSCs) using the 0.2 wt%of reduced graphene oxide and TiO2 nanoparticles (RGO+TiO2 nanocomposite) photoanode is investigated. CdS QDs are adsorbed onto RGO+TiO2 nanocomposite films by the successive ionic layer adsorption and reaction (SILAR) technique for several cycles. The current density–voltage (J–V ) characteristic curves of the assembled QDSSCs are measured at AM1.5 sim-ulated sunlight. The optimal photovoltaic performance for CdS QDSSC was achieved for six SILAR cycles. Solar cells based on the RGO+TiO2 nanocomposite photoanode achieve a 33%increase in conversion efficiency (η) compared with those based on plain TiO2 nanoparticle (NP) photoanodes. The electron back recombination rates decrease significantly for CdS QDSSCs based on RGO+TiO2 nanocomposite photoanodes. The lifetime constant (τ) for CdS QDSSC based on the RGO+TiO2 nanocomposite photoanode is at least one order of magnitude larger than that based on the bare TiO2NPs photoanode.

  12. Quantum dots sensitized titanium dioxide decorated reduced graphene oxide for visible light excited photoelectrochemical biosensing at a low potential.

    Science.gov (United States)

    Zeng, Xianxiang; Bao, Jianchun; Han, Min; Tu, Wenwen; Dai, Zhihui

    2014-04-15

    A low potential and competitive photoelectrochemical biosensing platform was developed using quantum dots sensitized titanium dioxide decorated reduced graphene oxide (TiO2-RGO) nanocomposites. The nanocomposites were prepared through electrostatic interaction between mercaptoacetic acid wrapped CdSe quantum dots with negative charge and TiO2-RGO hybrids with positive charge obtained via ultrasonic and acid treatments. Electron microscopes and spectroscopes were used to characterize the functionalized nanocomposites films of CdSe/TiO2-RGO, and the fabrication process of the photoelectrochemical biosensor. Based on the high photovoltaic conversion efficiency of CdSe/TiO2-RGO nanocomposites films, after introducing biological recognition and competitive immunoreaction, a low potential and competitive photoelectrochemical biosensor for carcinoembryonic antigen (CEA) detection was fabricated. The synergic effect of horseradish peroxide and benzo-4-chlorohexadienone decreased the background signal, leading to signal amplification. Under the light irradiation of 430 nm and the applied potential of 0 V, the biosensor detected CEA with a linear range from 0.003 to 100 ng mL(-1) and the detection limit was estimated to be 1.38 pg mL(-1) at a S/N of 3. It was satisfactory for clinical sample detection. The proposed competitive and low potential photoelectrochemical biosensor under irradiation of visible light exhibited good performance, which has a promising prospect in clinical diagnose.

  13. 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

  14. 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)

  15. Functional genomics analysis of horseweed (Conyza canadensis) with special reference to the evolution of non-target-site glyphosate resistance

    Science.gov (United States)

    The evolution of glyphosate resistance in weedy species places an environmentally benign herbicide in peril. The first report of a dicot plant with evolved glyphosate resistance was horseweed, which occurred in 2001. Since then, several species have evolved glyphosate resistance and genomic informat...

  16. 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...

  17. Development of Novel Glyphosate-Tolerant Japonica Rice Lines: A Step Toward Commercial Release

    Science.gov (United States)

    Cui, Ying; Huang, Shuqing; Liu, Ziduo; Yi, Shuyuan; Zhou, Fei; Chen, Hao; Lin, Yongjun

    2016-01-01

    Glyphosate is the most widely used herbicide for its low cost and high efficiency. However, it is rarely applied directly in rice field due to its toxicity to rice. Therefore, glyphosate-tolerant rice can greatly decrease the cost of rice production and provide a more effective weed management strategy. Although, several approaches to develop transgenic rice with glyphosate tolerance have been reported, the agronomic performances of these plants have not been well evaluated, and the feasibility of commercial production has not been confirmed yet. Here, a novel glyphosate-tolerant gene cloned from the bacterium Isoptericola variabilis was identified, codon optimized (designated as I. variabilis-EPSPS*), and transferred into Zhonghua11, a widely used japonica rice cultivar. After systematic analysis of the transgene integration via PCR, Southern blot and flanking sequence isolation, three transgenic lines with only one intact I. variabilis-EPSPS* expression cassette integrated into intergenic regions were identified. Seed test results showed that the glyphosate tolerance of the transgenic rice was about 240 times that of wild type on plant medium. The glyphosate tolerance of transgenic rice lines was further evaluated based on comprehensive agronomic performances in the field with T3 and T5generations in a 2-year assay, which showed that they were rarely affected by glyphosate even when the dosage was 8400 g ha−1. To our knowledge, this is the first demonstration of the development of glyphosate-tolerant rice lines based on a comprehensive analysis of agronomic performances in the field. Taken together, the results suggest that the selected glyphosate-tolerant rice lines are highly tolerant to glyphosate and have the possibility of commercial release. I. variabilis-EPSPS* also can be a promising candidate gene in other species for developing glyphosate-tolerant crops. PMID:27625652

  18. 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.

  19. Development of Novel Glyphosate-Tolerant Japonica Rice Lines: A Step Toward Commercial Release.

    Science.gov (United States)

    Cui, Ying; Huang, Shuqing; Liu, Ziduo; Yi, Shuyuan; Zhou, Fei; Chen, Hao; Lin, Yongjun

    2016-01-01

    Glyphosate is the most widely used herbicide for its low cost and high efficiency. However, it is rarely applied directly in rice field due to its toxicity to rice. Therefore, glyphosate-tolerant rice can greatly decrease the cost of rice production and provide a more effective weed management strategy. Although, several approaches to develop transgenic rice with glyphosate tolerance have been reported, the agronomic performances of these plants have not been well evaluated, and the feasibility of commercial production has not been confirmed yet. Here, a novel glyphosate-tolerant gene cloned from the bacterium Isoptericola variabilis was identified, codon optimized (designated as I. variabilis-EPSPS (*)), and transferred into Zhonghua11, a widely used japonica rice cultivar. After systematic analysis of the transgene integration via PCR, Southern blot and flanking sequence isolation, three transgenic lines with only one intact I. variabilis-EPSPS (*) expression cassette integrated into intergenic regions were identified. Seed test results showed that the glyphosate tolerance of the transgenic rice was about 240 times that of wild type on plant medium. The glyphosate tolerance of transgenic rice lines was further evaluated based on comprehensive agronomic performances in the field with T3 and T5generations in a 2-year assay, which showed that they were rarely affected by glyphosate even when the dosage was 8400 g ha(-1). To our knowledge, this is the first demonstration of the development of glyphosate-tolerant rice lines based on a comprehensive analysis of agronomic performances in the field. Taken together, the results suggest that the selected glyphosate-tolerant rice lines are highly tolerant to glyphosate and have the possibility of commercial release. I. variabilis-EPSPS (*) also can be a promising candidate gene in other species for developing glyphosate-tolerant crops.

  20. 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.

  1. Glyphosate, pathways to modern diseases II: Celiac sprue and gluten intolerance.

    Science.gov (United States)

    Samsel, Anthony; Seneff, Stephanie

    2013-12-01

    Celiac disease, and, more generally, gluten intolerance, is a growing problem worldwide, but especially in North America and Europe, where an estimated 5% of the population now suffers from it. Symptoms include nausea, diarrhea, skin rashes, macrocytic anemia and depression. It is a multifactorial disease associated with numerous nutritional deficiencies as well as reproductive issues and increased risk to thyroid disease, kidney failure and cancer. Here, we propose that glyphosate, the active ingredient in the herbicide, Roundup(®), is the most important causal factor in this epidemic. Fish exposed to glyphosate develop digestive problems that are reminiscent of celiac disease. Celiac disease is associated with imbalances in gut bacteria that can be fully explained by the known effects of glyphosate on gut bacteria. Characteristics of celiac disease point to impairment in many cytochrome P450 enzymes, which are involved with detoxifying environmental toxins, activating vitamin D3, catabolizing vitamin A, and maintaining bile acid production and sulfate supplies to the gut. Glyphosate is known to inhibit cytochrome P450 enzymes. Deficiencies in iron, cobalt, molybdenum, copper and other rare metals associated with celiac disease can be attributed to glyphosate's strong ability to chelate these elements. Deficiencies in tryptophan, tyrosine, methionine and selenomethionine associated with celiac disease match glyphosate's known depletion of these amino acids. Celiac disease patients have an increased risk to non-Hodgkin's lymphoma, which has also been implicated in glyphosate exposure. Reproductive issues associated with celiac disease, such as infertility, miscarriages, and birth defects, can also be explained by glyphosate. Glyphosate residues in wheat and other crops are likely increasing recently due to the growing practice of crop desiccation just prior to the harvest. We argue that the practice of "ripening" sugar cane with glyphosate may explain the recent

  2. 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

  3. Development of Novel Glyphosate-Tolerant Japonica Rice Lines: A Step Toward Commercial Release.

    Science.gov (United States)

    Cui, Ying; Huang, Shuqing; Liu, Ziduo; Yi, Shuyuan; Zhou, Fei; Chen, Hao; Lin, Yongjun

    2016-01-01

    Glyphosate is the most widely used herbicide for its low cost and high efficiency. However, it is rarely applied directly in rice field due to its toxicity to rice. Therefore, glyphosate-tolerant rice can greatly decrease the cost of rice production and provide a more effective weed management strategy. Although, several approaches to develop transgenic rice with glyphosate tolerance have been reported, the agronomic performances of these plants have not been well evaluated, and the feasibility of commercial production has not been confirmed yet. Here, a novel glyphosate-tolerant gene cloned from the bacterium Isoptericola variabilis was identified, codon optimized (designated as I. variabilis-EPSPS (*)), and transferred into Zhonghua11, a widely used japonica rice cultivar. After systematic analysis of the transgene integration via PCR, Southern blot and flanking sequence isolation, three transgenic lines with only one intact I. variabilis-EPSPS (*) expression cassette integrated into intergenic regions were identified. Seed test results showed that the glyphosate tolerance of the transgenic rice was about 240 times that of wild type on plant medium. The glyphosate tolerance of transgenic rice lines was further evaluated based on comprehensive agronomic performances in the field with T3 and T5generations in a 2-year assay, which showed that they were rarely affected by glyphosate even when the dosage was 8400 g ha(-1). To our knowledge, this is the first demonstration of the development of glyphosate-tolerant rice lines based on a comprehensive analysis of agronomic performances in the field. Taken together, the results suggest that the selected glyphosate-tolerant rice lines are highly tolerant to glyphosate and have the possibility of commercial release. I. variabilis-EPSPS (*) also can be a promising candidate gene in other species for developing glyphosate-tolerant crops. PMID:27625652

  4. Glyphosate resistance in tall waterhemp (Amaranthus tuberculatus) from Mississippi is due to both altered target-site and nontarget-site mechanisms

    Science.gov (United States)

    A tall waterhemp population in a glyphosate-resistant soybean field, Washington County, Missisippi, was suspected to be resistant to glyphosate. Glyphosate dose response experiments resulted in GR50 (glyphosate dose required to cause a 50% reduction in growth of treated plants) values of 1.28 and 0....

  5. Toxicity on the Interaction of Aluminum and Glyphosate to Greengrocery%铝与除草剂草甘膦的交互作用对青菜的毒理作用

    Institute of Scientific and Technical Information of China (English)

    贺根和; 钟文军; 谢坤

    2011-01-01

    The interaction toxicity of aluminum and glyphosate to greengrocery germination, sprout length and root elongation was studied. The results indicated that aluminum and glyphosate significantly affected growth of greengrocery. Low concentration of aluminum decreased the glyphosate's toxicity to germination, sprout length and root elongation of greengrocery to some extent,while low concentration of glyphosate could reduce aluminum's toxicity to sprout length. The toxicity of mixture of aluminum and glyphosate could be found as joint action at high concentration, and the strongest toxicity was showed when the highest aluminum and glyphosate concentration were added.%以青菜为供试材料,研究铝与除草荆草甘膦的交互作用时青菜种子的发芽势以及发芽后青菜种子的根长和芽长的影响.结果表明,铝与草甘膦对青菜表现比较明显的生长抑制作用,低浓度的铝能在一定程度上缓解草甘膦对青菜种子的发芽势、根长和芽长的抑制作用,而低浓度的草甘膦在一定程度上降低了铝对青菜种子发芽势和芽长的毒性.在高浓度下,两者均表现出对青菜种子的发芽势、根长和芽长的联合毒性,并在最高处理浓度时,毒性最强.

  6. 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

    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.

  7. Identification of geneticaly modified soybean seeds resistant to glyphosate

    OpenAIRE

    Tillmann Maria Ângela André; West Shirlie

    2004-01-01

    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 ...

  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.

  9. Toxicity of the herbicide glyphosate to Chordodes nobilii (Gordiida, Nematomorpha).

    Science.gov (United States)

    Achiorno, Cecilia L; Villalobos, Cristina de; Ferrari, Lucrecia

    2008-05-01

    Nematomorpha (horsehair worms) is a poorly known group of worm-like animals similar to nematodes. Adults are free-living and reproduction takes place in freshwater environments, where preparasitic larvae undergo development. All species have a parasitic juvenil stage and infection may result in the host's death, insects being the most frequent host. Most of the life cycle occurs in freshwater environments, which are often contaminated by different pollutants. Based on the lack of information on the toxicity of herbicides to horsehair worms, the objective of this study is to evaluate the effect of different concentrations of glyphosate (technical grade and formulated product) on Chordodes nobilii (Gordiida, Nematomorpha). Bioassays were performed with embryos and larvae (preparasitic stages), and adults (postparasitic stage). Test organisms were exposed for a short period of time to concentrations ranging between 0.1 and 8 mga.e.l(-1) of glyphosate (technical and formulated). Although embryo development was not inhibited, there was a significant decrease in the infective capacity of larvae derived from eggs that had been exposed to >or= 0.1mg/l. Similar results were obtained for directly exposed larvae. No differences in toxicity were detected between the active ingredient and formulated product. Adult exposed for 96 h to 1.76 mgl(-1) formulated Gly shown a mortality of 50%. Results indicate that C. nobilii is affected at glyphosate concentrations lower than those expected to be found in freshwater environments and those specified in the legislation.

  10. 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.

  11. Annual glyphosate treatments alter growth of unaffected bentgrass (Agrostis) weeds and plant community composition.

    Science.gov (United States)

    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 application. Five field plots were studied in habitats commonly inhabited by weedy bentgrasses including an agricultural hayfield, natural meadow, and wasteland. Results showed that annual glyphosate treatment improved bentgrass survivorship, vegetative growth, and reproductive potential compared with bentgrass in unsprayed subplots. In the second year of growth, RT plants had an 86-fold increase in flower number in glyphosate-treated subplots versus controls, while CB plants had a 20-fold increase. At the end of the three year study, plant community composition had changed in glyphosate-treated subplots in hayfield and meadow plots compared to controls. Soils in subplots receiving glyphosate had higher nitrate concentrations than controls. This is the first study to mimic the GR trait in bentgrass plants with the goal of quantifying bentgrass response to glyphosate selection pressure and understanding the impacts on surrounding plant communities.

  12. Mechanism of resistance of evolved glyphosate-resistant Palmer amaranth (Amaranthus palmeri).

    Science.gov (United States)

    Gaines, Todd A; Shaner, Dale L; Ward, Sarah M; Leach, Jan E; Preston, Christopher; Westra, Philip

    2011-06-01

    Evolved glyphosate resistance in weedy species represents a challenge for the continued success and utility of glyphosate-resistant crops. Glyphosate functions by inhibiting the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS). The resistance mechanism was determined in a population of glyphosate-resistant Palmer amaranth from Georgia (U.S.). Within this population, glyphosate resistance correlates with increases in (a) genomic copy number of EPSPS, (b) expression of the EPSPS transcript, (c) EPSPS protein level, and (d) EPSPS enzymatic activity. Dose response results from the resistant and an F(2) population suggest that between 30 and 50 EPSPS genomic copies are necessary to survive glyphosate rates between 0.5 and 1.0 kg ha(-1). These results further confirm the role of EPSPS gene amplification in conferring glyphosate resistance in this population of Palmer amaranth. Questions remain related to how the EPSPS amplification initially occurred and the occurrence of this mechanism in other Palmer amaranth populations and other glyphosate-resistant species.

  13. Differential susceptibility and resistance to glyphosate in annual ryegrass and wavy-leaved fleabane

    Directory of Open Access Journals (Sweden)

    Flávia Regina da Costa

    2014-09-01

    Full Text Available Annual ryegrass (Lolium multiflorum and wavy-leaved fleabane (Conyza bonariensis were tested, aiming to investigate the dose-response of biotypes of both species to glyphosate. Glyphosate herbicide at doses varying from 0 up to 1.440 g e.a. ha-1 was sprayed onto annual ryegrass plants showed four leaves and wavy-leaved fleabane showed three pair of leaves. The fresh weight of shoot was obtained at 21 days after herbicide application. The response of biotypes of L. multiflorum and C. bonariensis to glyphosate was clearly different. For L. multiflorum, the S2, R1, and R3 biotypes supported glyphosate doses 1.5, 3.0, and 8.3 times higher than the biotype S1. For C. bonariensis, the S2 and R biotypes supported glyphosate doses 2.0 and 15.5 times higher than the biotype S1. We found a low glyphosate-resistant (R1 and a high glyphosate-resistant (R2 biotypes of L. multiflorum, in agricultural regions where other biotypes had been found. In addition, a high glyphosate-resistant (R biotype of C. bonariensis was identified in an agricultural area of Santa Catarina State, Brazil, where weed resistant was not previously found.

  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. Involvement of facultative apomixis in inheritance of EPSPS gene amplification in glyphosate-resistant Amaranthus palmeri

    Science.gov (United States)

    The inheritance of glyphosate resistance in two Amaranthus palmeri populations (R1 and R2) was examined in reciprocal crosses (RC) and second reciprocal crosses (2RC) between glyphosate-resistant (R) and -susceptible (S) parents of this dioecious species. R populations and Female-R × Male-S crosses...

  16. 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...

  17. 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...

  18. 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...

  19. Stimulation of bacteria and protists in rhizosphere of glyphosate-treated barley

    DEFF Research Database (Denmark)

    Imparato, Valentina; Santos, Susana; Johansen, Anders;

    2016-01-01

    treatments with no effect on total abundance. Also the abundance of culturable protists increased as an effect of glyphosate and the bacterial genetic diversity as revealed by 16S rDNA DGGE analysis was affected. Overall, the results indicate that when barley leaves are treated with glyphosate...

  20. 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.

  1. 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)

  2. Goss’s wilt incidence in sweet corn is independent of transgenic traits and glyphosate

    Science.gov (United States)

    Recently claims have been made that the use of glyphosate and transgenic crop traits increases the risk of plant diseases. Transgenic traits used widely for years in dent corn are now available in commercial sweet corn cultivars, specifically, the combination of glyphosate resistance (GR) and Lepid...

  3. Short-term transport of glyphosate with erosion in Chinese loess soil - a flume experiment

    NARCIS (Netherlands)

    Yang, X.; Wang, Fei; Martins Bento, Celia; Xue, Sha; Gai, L.; Dam, van R.C.J.; Mol, J.G.J.; Ritsema, C.J.; Geissen, V.

    2015-01-01

    Repeated applications of glyphosate may contaminate the soil and water and threaten their quality both within the environmental system and beyond it through water erosion related processes and leaching. In this study, we focused on the transport of glyphosate and its metabolite aminomethylphosphonic

  4. Decay characteristics and erosion-related transport of glyphosate in Chinese loess soil under field conditions

    NARCIS (Netherlands)

    Yang, X.; Wang, Fei; Martins Bento, Celia; Meng, L.; Dam, van R.C.J.; Mol, J.G.J.; Liu, Guobin; Ritsema, C.J.; Geissen, V.

    2015-01-01

    The decay characteristics and erosion-related transport of glyphosate and aminomethylphosphonic acid (AMPA) were monitored for 35 d at different slope gradients and rates of application in plots with loess soil on the Loess Plateau, China. The initial glyphosate decayed rapidly (half-life of 3.5 d)

  5. Fate and transport of glyphosate and aminomethylphosphonic acid in surface waters of agricultural basins

    Science.gov (United States)

    Coupe, R.H.; Kalkhoff, S.J.; Capel, P.D.; Gregoire, C.

    2012-01-01

    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. Results: Glyphosate and AMPA were frequently detected in the surface waters of four agricultural basins. The frequency and magnitude of detections varied across basins, and the load, as a percentage of use, ranged from 0.009 to 0.86% and could be related to three general characteristics: source strength, rainfall runoff and flow route. Conclusions: Glyphosate use in a watershed results in some occurrence in surface water; however, the watersheds most at risk for the offsite transport of glyphosate are those with high application rates, rainfall that results in overland runoff and a flow route that does not include transport through the soil. ?? 2011 Society of Chemical Industry.

  6. Annual glyphosate treatments alter growth of unaffected bentgrass (Agrostis weeds and plant community composition.

    Directory of Open Access Journals (Sweden)

    Collin W Ahrens

    Full Text Available 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 application. Five field plots were studied in habitats commonly inhabited by weedy bentgrasses including an agricultural hayfield, natural meadow, and wasteland. Results showed that annual glyphosate treatment improved bentgrass survivorship, vegetative growth, and reproductive potential compared with bentgrass in unsprayed subplots. In the second year of growth, RT plants had an 86-fold increase in flower number in glyphosate-treated subplots versus controls, while CB plants had a 20-fold increase. At the end of the three year study, plant community composition had changed in glyphosate-treated subplots in hayfield and meadow plots compared to controls. Soils in subplots receiving glyphosate had higher nitrate concentrations than controls. This is the first study to mimic the GR trait in bentgrass plants with the goal of quantifying bentgrass response to glyphosate selection pressure and understanding the impacts on surrounding plant communities.

  7. 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...

  8. 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 ...

  9. Inheritance of Evolved Glyphosate Resistance in a North Carolina Palmer Amaranth (Amaranthus palmeri Biotype

    Directory of Open Access Journals (Sweden)

    Aman Chandi

    2012-01-01

    Full Text Available Inheritance of glyphosate resistance in a Palmer amaranth biotype from North Carolina was studied. Glyphosate rates for 50% survival of glyphosate-resistant (GR and glyphosate-susceptible (GS biotypes were 1288 and 58 g ha−1, respectively. These values for F1 progenies obtained from reciprocal crosses (GR×GS and GS×GR were 794 and 501 g ha−1, respectively. Dose response of F1 progenies indicated that resistance was not fully dominant over susceptibility. Lack of significant differences between dose responses for reciprocal F1 families suggested that genetic control of glyphosate resistance was governed by nuclear genome. Analysis of F1 backcross (BC1F1 families showed that 10 and 8 BC1F1 families out of 15 fitted monogenic inheritance at 2000 and 3000 g ha−1 glyphosate, respectively. These results indicate that inheritance of glyphosate resistance in this biotype is incompletely dominant, nuclear inherited, and might not be consistent with a single gene mechanism of inheritance. Relative 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS copy number varied from 22 to 63 across 10 individuals from resistant biotype. This suggested that variable EPSPS copy number in the parents might be influential in determining if inheritance of glyphosate resistance is monogenic or polygenic in this biotype.

  10. Glyphosate: environmental contamination, toxicity and potential risks to human health via food contamination.

    Science.gov (United States)

    Bai, Shahla Hosseini; Ogbourne, Steven M

    2016-10-01

    Glyphosate has been the most widely used herbicide during the past three decades. The US Environmental Protection Agency (EPA) classifies glyphosate as 'practically non-toxic and not an irritant' under the acute toxicity classification system. This classification is based primarily on toxicity data and due to its unique mode of action via a biochemical pathway that only exists in a small number of organisms that utilise the shikimic acid pathway to produce amino acids, most of which are green plants. This classification is supported by the majority of scientific literature on the toxic effects of glyphosate. However, in 2005, the Food and Agriculture Organisation (FAO) reported that glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), are of potential toxicological concern, mainly as a result of accumulation of residues in the food chain. The FAO further states that the dietary risk of glyphosate and AMPA is unlikely if the maximum daily intake of 1 mg kg(-1) body weight (bw) is not exceeded. Research has now established that glyphosate can persist in the environment, and therefore, assessments of the health risks associated with glyphosate are more complicated than suggested by acute toxicity data that relate primarily to accidental high-rate exposure. We have used recent literature to assess the possible risks associated with the presence of glyphosate residues in food and the environment.

  11. Resistência de genótipos de soja ao herbicida glyphosate Resistance of soybean genotypes to glyphosate

    Directory of Open Access Journals (Sweden)

    E Matsuo

    2009-12-01

    Full Text Available Avaliou-se a resistência de dez genótipos de soja (Glycine max ao herbicida glyphosate. Foi adotado o esquema fatorial 10 x 4, no delineamento em blocos casualizados, com quatro repetições. O fator A foi composto por dez genótipos de soja, e o B, por quatro doses de glyphosate. A aplicação do herbicida foi realizada no momento em que as plantas de soja apresentavam a segunda folha trifoliolada completamente desenvolvida. Avaliaramse os caracteres: intoxicação das plantas, número de nós da haste principal, altura das plantas e massa seca das plantas. Na avaliação da intoxicação de plantas, tanto aos quatro dias após a aplicação (DAA do herbicida quanto aos 28 DAA, os genótipos convencionais apresentaram médias superiores estatisticamente em comparação com genótipos resistentes ao glyphosate (RR. Verificou-se que, nas avaliações realizadas ao 0 DAA ou aos 28 DAA sob 0,0 g e.a. ha¹, as respostas dos genótipos foram diferentes em todos os caracteres avaliados, com exceção do número de nós aos 28 DAA. Essas diferenças podem ser atribuídas aos efeitos fisiológicos e ambientais ou a características do próprio material. Nas demais doses, os genótipos RR comportaram-se de maneira desejável em detrimento dos genótipos convencionais. Ao considerar todos os caracteres avaliados, pode-se afirmar que Valiosa RR, BCR945G110, BCR945G114, BCR892G132, BCR892G140, BCR1067G210, BCR1070G244 e M-SOY 8008RR comportaram-se de forma semelhante quanto à resistência ao glyphosate quando submetidos até a dose de 2.160 g e.a. ha-1 .Resistance of ten soybean genotypes (Glycine max to the herbicide glyphosate was evaluated. The randomized block experimental design was used under factorial scheme 10 x 4 and four replicates. Factor A was composed of 10 soybean genotypes and factor B of four glyphosate doses. The herbicide was applied when the second trifoliate leaf of the soybean plants was completely developed. The following characters

  12. Effect of glyphosate-boron application on seed composition and nitrogen metabolism in glyphosate-resistant soybean.

    Science.gov (United States)

    Bellaloui, Nacer; Abbas, Hamed K; Gillen, Anne M; Abel, Craig A

    2009-10-14

    The objective of this study was to evaluate the effects of foliar application of glyphosate (Gly) alone, boron (B) alone, and Gly-B combined on seed composition and nitrogen metabolism in glyphosate-resistant soybean (Glycine max (L.) Merr.). No Gly and no B application plants were used as control (C). Results showed that Gly, Gly-B, or B applications increased protein, oleic acid, and total amino acid concentrations in seed. However, oil and linolenic acid concentrations decreased under those treatments compared with the nontreated control. Gly-B combined or B treatments increased B concentration in leaves and seed, nitrate reductase activity (NRA), and nitrogenase activity and resulted in a significant positive correlation between B concentration in leaves and NRA (r = 0.54; P application alters seed composition, nitrogen metabolism, and B status in leaves and seed.

  13. Determination of glyphosate and its metabolite in emergency room in Korea.

    Science.gov (United States)

    Han, Joseph; Moon, Hantae; Hong, Youngki; Yang, Songhee; Jeong, Won-Joon; Lee, Kwang-Sik; Chung, Heesun

    2016-08-01

    The number of glyphosate intoxication cases has been increased after the regulation of paraquat. Unfortunately, there are no reports on the potential concentration of glyphosate for those acute intoxicated patients admitted to emergency rooms and the correlation between the concentration of glyphosate and clinical symptoms in Korea up to our knowledge. As a nonselective herbicide, analysis of glyphosate requires derivatization because of its amphoteric and strongly polar nature. In order to develop a method to determine the concentration of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA) in blood samples without derivatization, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was utilized with a hydrophilic interaction chromatography (HILIC) column. The validation of this method showed that the limits of detection (LODs) and limits of quantitation (LOQs) for glyphosate and AMPA were 50 and 100ng/mL, respectively. In addition, matrix effect, recovery rate, and accuracy and precision in intra and inter-day were evaluated during the validation study of this method. Blood samples acquired from five glyphosate intoxicated patients were analyzed to investigate the correlation between the concentration of glyphosate and clinical symptoms. These patients were previously admitted to the emergency room at a University Hospital in Korea after glyphosate was self-administered in suicide attempts or by accident. As results of blood sample study, the concentration of glyphosate and AMPA were found in the range of 1.0-171.1 and 0.2-2.6μg/mL, respectively. The concentration ratio of glyphosate to AMPA was 55-71. According to the clinical reports for those patients, they were in the age between 47 and 82 years old and administered about 50-400mL. The blood samples were collected within 2-5h after administration of glyphosate. Among the intoxicated patients, the most common clinical symptom was metabolic acidosis, identified in four patients

  14. Determination of glyphosate and its metabolite in emergency room in Korea.

    Science.gov (United States)

    Han, Joseph; Moon, Hantae; Hong, Youngki; Yang, Songhee; Jeong, Won-Joon; Lee, Kwang-Sik; Chung, Heesun

    2016-08-01

    The number of glyphosate intoxication cases has been increased after the regulation of paraquat. Unfortunately, there are no reports on the potential concentration of glyphosate for those acute intoxicated patients admitted to emergency rooms and the correlation between the concentration of glyphosate and clinical symptoms in Korea up to our knowledge. As a nonselective herbicide, analysis of glyphosate requires derivatization because of its amphoteric and strongly polar nature. In order to develop a method to determine the concentration of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA) in blood samples without derivatization, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was utilized with a hydrophilic interaction chromatography (HILIC) column. The validation of this method showed that the limits of detection (LODs) and limits of quantitation (LOQs) for glyphosate and AMPA were 50 and 100ng/mL, respectively. In addition, matrix effect, recovery rate, and accuracy and precision in intra and inter-day were evaluated during the validation study of this method. Blood samples acquired from five glyphosate intoxicated patients were analyzed to investigate the correlation between the concentration of glyphosate and clinical symptoms. These patients were previously admitted to the emergency room at a University Hospital in Korea after glyphosate was self-administered in suicide attempts or by accident. As results of blood sample study, the concentration of glyphosate and AMPA were found in the range of 1.0-171.1 and 0.2-2.6μg/mL, respectively. The concentration ratio of glyphosate to AMPA was 55-71. According to the clinical reports for those patients, they were in the age between 47 and 82 years old and administered about 50-400mL. The blood samples were collected within 2-5h after administration of glyphosate. Among the intoxicated patients, the most common clinical symptom was metabolic acidosis, identified in four patients

  15. WEED CONTROL IN GENETICALLY MODIFIED GLYPHOSATE-TOLERANT SOYBEAN MANEJO DE PLANTAS DANINHAS EM SOJA GENETICAMENTE MODIFICADA TOLERANTE AO GLYPHOSATE

    OpenAIRE

    Júlio Cezar Durigan; Núbia Maria Correia; Melina Espanhol

    2011-01-01

    The transgenic production systems, as well as conventional systems, require, in addition to chemical control, the adoption of other weed management strategies. This study was developed to evaluate the weed chemical control in glyphosate tolerant soybean, associated to cover crops cultivated in the autumn/winter. The experiment was carried out under field conditions at the FCAV/Unesp, Jaboticabal, São Paulo State, Brazil. A randomized split-plot block design was used, with four replications. S...

  16. 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.

  17. Molecular basis of glyphosate resistance-different approaches through protein engineering.

    Science.gov (United States)

    Pollegioni, Loredano; Schonbrunn, Ernst; Siehl, Daniel

    2011-08-01

    Glyphosate (N-phosphonomethyl-glycine) is the most widely 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 attributable to the high specificity of glyphosate for the plant enzyme enolpyruvyl shikimate-3-phosphate synthase in the shikimate pathway, leading to the biosynthesis of aromatic amino acids. Starting in 1996, transgenic glyphosate-resistant plants were introduced, thus allowing application of the herbicide to the crop (post-emergence) to remove emerged weeds without crop damage. This review focuses on mechanisms of resistance to glyphosate as obtained through natural diversity, the gene-shuffling approach to molecular evolution, and a rational, structure-based approach to protein engineering. In addition, we offer a rationale for the means by which the modifications made have had their intended effect.

  18. Glyphosate impacts on polyphenolic composition in grapevine (Vitis vinifera L.) berries and wine.

    Science.gov (United States)

    Donnini, Silvia; Tessarin, Paola; Ribera-Fonseca, Alejandra; Di Foggia, Michele; Parpinello, Giuseppina Paola; Rombolà, Adamo Domenico

    2016-12-15

    Glyphosate is the most widespread herbicide for weed management, being extensively used in viticulture. In this study we tested, under field conditions, the effects of glyphosate applications on the quality of berry and wine, from cv. Ancellotta (Vitis vinifera L.), with particular regard to anthocyanin concentration and composition. Ripening and growth were monitored by analyzing berry technological parameters and weight. Additionally, microvinifications were performed, in order to analyze the concentration of anthocyanins, other flavonoids and phenolic acids in wine. Our findings indicated that, at harvest, both pH and anthocyanin concentration were significantly lower and titratable acidity higher in berries collected from vines of plots under glyphosate-treatment compared with those of non-treated parcels. Data suggest that treatment with glyphosate did not change the concentration of anthocyanins, other flavonoids and phenolic acids in the wine. Our results indicate that treatment with glyphosate may affect fruit metabolism and nutritional value in non-target plants.

  19. New bacterial strain of the genus Ochrobactrum with glyphosate-degrading activity.

    Science.gov (United States)

    Hadi, Faranak; Mousavi, Amir; Noghabi, Kambiz Akbari; Tabar, Hadi Ghaderi; Salmanian, Ali Hatef

    2013-01-01

    Thirty bacterial strains with various abilities to utilize glyphosate as the sole phosphorus source were isolated from farm soils using the glyphosate enrichment cultivation technique. Among them, a strain showing a remarkable glyphosate-degrading activity was identified by biochemical features and 16S rRNA sequence analysis as Ochrobactrum sp. (GDOS). Herbicide (3 mM) degradation was induced by phosphate starvation, and was completed within 60 h. Aminomethylphosphonic acid was detected in the exhausted medium, suggesting glyphosate oxidoreductase as the enzyme responsible for herbicide breakdown. As it grew even in the presence of glyphosate concentrations as high as 200 mM, Ochrobactrum sp. could be used for bioremediation purposes and treatment of heavily contaminated soils.

  20. 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.