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.

Improvement of Soybean (Glycine max L. Yield with Urea Foliar Application at Growth Stages

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Mahmood Tohidi

2017-07-01

Full Text Available To investigate the effects of nitrogen foliar application at different growth stages of soybean on the yield and yield components this experiment was performed in Shush, north of Khuzestan, Iran, during growing season of 2014. The experiment was in split plot based on randomized complete block design with three replications. Experimental treatments consisted of four levels of nitrogen fertilizer foliar applications as control (no nitrogen foliar application, 25, 50 and 75 kg/ha pure nitrogen from urea source (46% pure nitrogen assigned to the main plots and spraying times in three levels, at vegetative stage, flowering stage and podding stage to the subplots. Results showed that the effects of nitrogen foliar application on traits measured in this experiment like leaf area index, number of pod per plant, number of seeds per pod, thousand seed weight, seed yield, biologic yield, harvest index, protein percent and protein yield and also interaction of different levels of nitrogen foliar application and different growth stages, were significant. Oil percent and yield were only significant under the effect of nitrogen foliar application treatments at different growth stages while the interaction of different levels of nitrogen foliar application and different growth stages, were not significant. In this experiment nitrogen foliar application increased seed yield. The highest seed yield amounted to 2466 kg/ha when 50kg/ha of foliar nitrogen applied at vegetative growth stage and lowest seed yield amounted to 1295 kg/ha in the control treatment at the stage of podding. In general, results demonstrated that 50 kg/ha treatment could be considered as the best management option of nitrogen foliar application for soybean at vegetative growth stage.

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

International Nuclear Information System (INIS)

Mamy, Laure; Gabrielle, Benoit; Barriuso, 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 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.

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.

Foliar Desiccators Glyphosate, Carfentrazone, and Paraquat Affect the Technological and Chemical Properties of Cowpea Grains.

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Lindemann, Igor da Silva; Lang, Gustavo Heinrich; Hoffmann, Jessica Fernanda; Rombaldi, Cesar Valmor; de Oliveira, Maurício; Elias, Moacir Cardoso; Vanier, Nathan Levien

2017-08-16

The effects of the use of glyphosate (GLY), glyphosate plus carfentrazone (GLY/CAR), and paraquat (PAR) as plant desiccators on the technological and chemical properties of cowpea grains were investigated. All studied desiccants provided lower cooking time to freshly harvested cowpea. However, the coat color of PAR- and GLY/CAR-treated cowpea was reddish in comparison to the control treatment. Principal component analysis (PCA) from liquid chromatography-mass spectrometry (LC-MS) data sets showed a clear distinction among cowpea from the different treatments. Catechin-3-glucoside and epicatechin significantly contributed for discriminating GLY-treated cowpea, while citric acid was responsible for discriminating GLY/CAR-treated cowpea. Quercetin derivative and gluconic acid were responsible for discriminating control treatment. Residual glyphosate and paraquat content was higher than the maximum limits allowed by Codex Alimentarius and the European Union Commission. Improvements in the technological and chemical properties of cowpea may not be overlapped by the risks that those desiccants exhibit when exceeding the maximum limits of tolerance in food.

Consequences of phosphate application on glyphosate uptake by roots: Impacts for environmental management practices.

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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. Copyright © 2015. Published by Elsevier B.V.

Foliar application of two silica sols reduced cadmium accumulation in rice grains

International Nuclear Information System (INIS)

Liu Chuanping; Li Fangbai; Luo Chunling; Liu Xinming; Wang Shihua; Liu Tongxu; Li Xiangdong

2009-01-01

In the present study, pot experiments were conducted to investigate the effects of foliar application of two silica (Si) sols on the alleviation of cadmium (Cd) toxicity in contaminated soil to rice. Results showed that the foliar application of Si sols significantly increased the dry weight of grains (without husk) and shoots in rice grown in Cd contaminated soil, whereas the Cd concentration in the grains and shoots decreased obviously. The total accumulation of Cd in rice grains also decreased with the application of both of the Si sols, but no significant effect was found on the Cd accumulation in the shoots. For the optimal effect, Si-sol-B should be foliar applied at the tillering-stage during rice growth. The mechanism of Si foliar application to alleviate the toxicity and accumulation of Cd in grains of rice may be related to the probable Cd sequestration in the shoot cell walls

Location, Root Proximity, and Glyphosate-use History Modulate the Effects of Glyphosate on Fungal Community Networks of Wheat

Science.gov (United States)

Glyphosate is the most-used herbicide worldwide and an essential tool for weed control in no-till cropping systems. However, concerns have been raised regarding the long-term effects of glyphosate on soil microbial communities. We examined the impact of repeated glyphosate application on bulk and rh...

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

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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.

Effects of Formulated Glyphosate and Adjuvant Tank Mixes on Atomization from Aerial Application Flat Fan Nozzles

Science.gov (United States)

2012-01-01

Bradley K. Fritz,1 W. Clint Hoffmann,1 and W. E. Bagley2 Effects of Formulated Glyphosate and Adjuvant Tank Mixes on Atomization from Aerial...Application Flat Fan Nozzles REFERENCE: Fritz, Bradley K., Hoffmann, W. Clint, and Bagley, W. E., “Effects of Formulated Glyphosate and Adjuvant Tank Mixes on...factors. Twelve spray-solution treatments were evaluated, ten of which contained a formulated glyphosate product and nine of these con- tained an

Glyphosate-resistant goosegrass from Mississippi

Science.gov (United States)

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

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

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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.

The Effect of Zinc Sulfate Different Amount Soil and Foliar Application on Correlated Grain Characters in Sweet Corn

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J. Mahmoodi,

2013-06-01

Full Text Available This research was conducted to evaluate the effects different concentrations of zinc sulfate applications at different growth stages on sweet corn at the Research Station of Faculty of Agriculture in Islamic Azad University, Tabriz branch in 2012. The study was conducted in split plot experiment based on Randomized Complete Block Design with three replications. Treatments were seven levels of zinc sulfate application methods: (control, soil application, foliar application at 6-8 leaf growth stage, tasseling, grain filling stage, foliar application at three stages, soil application with foliar application at three stages as main plot, three levels of foliar and soil application of zinc sulfate: (0.003, 0.005 and 0.007 for foliar application and 15, 25 and 35 kg/ha for soil application as sub plot. Results showed that the highest grain yield correlated characters were obtained in foliar application at three stages and soil application with foliar application at three stages. In these conditions increasing of dry grain yield and ear were more than 50%. The higher values for grain production were obtained in Zn foliar application with 0.005 concentration (25 kg/ha soil application. Zinc sulfate increased Zn content of grains produced more than 100%. Thus, using Zn not only increases sweet corn grain and ear yield but also increased quality of products.

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

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P.C. Magalhães

2001-08-01

Full Text Available A aplicação de herbicidas, seja para a dissecação de culturas ou para o controle de plantas daninhas, vem crescendo, devido a expansão da fronteira agrícola brasileira. Esse fato aumenta os riscos de ocorrência de deriva acidental em culturas vizinhas suscetíveis. As perdas em produtividade são desconhecidas em muitas situações de ocorrência de deriva de herbicidas. O objetivo deste trabalho foi avaliar a possível toxicidade causada pela deriva de doses reduzidas de dois herbicidas (glyphosate e paraquat no período inicial de desenvolvimento da cultura do milho. Foram utilizadas cinco doses simulando deriva - 2, 4, 6, 8 e 12% da dose recomendada (1.440 g ha-1 de glyphosate e 400 g ha-1 de paraquat - sobre o cultivar de milho híbrido triplo BRS 3123. No florescimento, foram avaliados altura da planta, área foliar, peso da matéria seca, teor de clorofila e sintomas visuais de injúria. Na colheita, avaliaram-se estande final, peso de espigas, peso de 1.000 grãos e produção de grãos. A altura das plantas, a área foliar e o peso da matéria seca não foram afetados pelo efeito das derivas nos dois anos agrícolas (1996/97 e 1997/98, exceto pela área foliar, que em 1997/98 sofreu redução, sobretudo no tratamento com 12% da dose normal de glyphosate. De maneira geral, os resultados obtidos para as demais características foram semelhantes nos dois anos de condução do ensaio. O teor de clorofila nas folhas e o estande final não foram afetados pelas doses reduzidas. O grau de toxicidade, avaliado por meio de plantas injuriadas pela deriva, aos 7, 14 e 21 dias após a aplicação dos herbicidas, apresentou diferenças significativas. Os maiores danos foram observados com a maior subdose simulando deriva dos herbicidas. O peso de 1.000 grãos não foi afetado, ao passo que a produção de espigas e de grãos foi severamente prejudicada. Observou-se que a deriva simulada dos herbicidas em altas concentrações afetou o

Soil microbial communities and glyphosate decay in soils with different herbicide application history.

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Guijarro, Keren Hernández; Aparicio, Virginia; De Gerónimo, Eduardo; Castellote, Martín; Figuerola, Eva L; Costa, José Luis; Erijman, Leonardo

2018-04-11

This study evaluates the glyphosate dissipation under field conditions in three types of soil, and aims to determine the importance of the following factors in the environmental persistence of herbicide: i) soil bacterial communities, ii) soil physicochemical properties, iii) previous exposure to the herbicide. A soil without previous record of GP application (P0) and two agricultural soils, with 5 and >10years of GP exposure (A5 and A10) were subjected to the application of glyphosate at doses of 3mg·kg -1 . The concentration of GP and AMPA was determined over time and the dynamics of soil bacterial communities was evaluated using 16S ARN ribosomal gene amplicon-sequencing. The GP exposure history affected the rate but not the extent of GP biodegradation. The herbicide was degraded rapidly, but P0 soil showed a dissipation rate significantly lower than soils with agricultural history. In P0 soil, a significant increase in the relative abundance of Bacteroidetes was observed in response to herbicide application. More generally, all soils displayed shifts in bacterial community structure, which nevertheless could not be clearly associated to glyphosate dissipation, suggesting the presence of redundant bacteria populations of potential degraders. Yet the application of the herbicide prompted a partial disruption of the bacterial association network of unexposed soil. On the other hand, higher values of linear (Kd) and nonlinear (Kf) sorption coefficient in P0 point to the relevance of cation exchange capacity (CEC), clay and organic matter to the capacity of soil to adsorb the herbicide, suggesting that bioavailability was a key factor for the persistence of GP and AMPA. These results contribute to understand the relationship between bacterial taxa exposed to the herbicide, and the importance of soil properties as predictors of the possible rate of degradation and persistence of glyphosate in soil. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of Foliar Application of Micro Nutrients on Physiological Growth Indices and Total Dry Matter Yield of Forage Corn

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A. Soleymani

2012-04-01

Full Text Available In order to evaluate the effect of foliar application of micro nutrients on physiological growth indices and total dry matter yield of forage corn. Field experiment was conducted in 2006 at Bersian village Isfahan. A randomized complete block design with four replications was used. Plant treated with 8 foliar application treatments (Fe, Zn, Cu, Mn, Fe + Mn, Cu + Zn, Fe + Mn + Cu + Zn and control. The responses to foliar application in total dry weight, LAI and CGR appeared to differ between the treatments, but there is no significant difference in NAR between the treatments. Maximum leaf area index gained in foliar application of Fe but there is significant difference between this treatment and other treatments except foliar application of Zn and Fe + Mn. Foliar application of Fe and Fe + Mn result to maximum total dry weight, but there is no significant difference between these treatments and foliar application of Zn, Mn, Mn + Cu and Fe + Zn + Cu +Mn. Maximum and minimum NAR gained in foliar application of Mn and control treatments respectively. Maximum CGR gained in foliar application of Zn, there is significant difference between this treatment and others. Control treatment in comparison with others shows minimum value in all measured factors. The results indicate that foliar application of micro nutrients particularly Fe and Fe+Mn may be suitable to product maximum total dry matter yield under similar condition.

Response of French Bean (Phaseolus vulgaris L. Cultivars to Foliar Applications of Magnesium

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Michele Pisante

2011-02-01

Full Text Available Magnesium deficiencies have been shown to be particularly dangerous to short cycled crops, both on sandy and clay soils. Such deficiencies may be corrected by foliar fertilisations, but in French bean (Phaseolus vulgaris L. no experimental data may be found to support this hypothesis. Therefore this paper was aimed at studying the effect of foliar Mg-applications (56, 112 and 224 g ha-1 in single application at flowering or splitted half dose at 4-leaf stage and half at flowering alone and with Zn (200 g ha-1 on yield and quality of two French bean genotypes (Bronco, Cadillac. Foliar Mg-applications significantly increased pod yield and, considering the highest rate with respect to the untreated, such an increase was 78% and 32% for Bronco and Cadillac, respectively. Split applications were also more effective, with yield increases of 109% and 50% for the two genotypes. Concerning quality, foliar Mg applications showed a significant effect particularly on sugars, calcium, phosphate, sulphate and Mg contents in pods. On the other hand, a significant effect on the accumulation of nitrates was noted, especially with split applications (144% increase vs. unfertilised and, in some cases, an antagonistic effect on K content (10-20% decrease on average. Foliar Mg fertilisation of French bean seemed to be a promising practice with reference to human health and nutrition, tough some care is needed to avoid the accumulation of nitrates in pods. Split applications seemed to be more effective, while the addition of Zn to the fertiliser mix did not give any relevant effect.

Impacts of Repeated Glyphosate Use on Wheat-Associated Bacteria Are Small and Depend on Glyphosate Use History.

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Schlatter, Daniel C; Yin, Chuntao; Hulbert, Scot; Burke, Ian; Paulitz, Timothy

2017-11-15

Glyphosate is the most widely used herbicide worldwide and a critical tool for weed control in no-till cropping systems. However, there are concerns about the nontarget impacts of long-term glyphosate use on soil microbial communities. We investigated the impacts of repeated glyphosate treatments on bacterial communities in the soil and rhizosphere of wheat in soils with and without long-term history of glyphosate use. We cycled wheat in the greenhouse using soils from 4 paired fields under no-till (20+-year history of glyphosate) or no history of use. At each cycle, we terminated plants with glyphosate (2× the field rate) or by removing the crowns, and soil and rhizosphere bacterial communities were characterized. Location, cropping history, year, and proximity to the roots had much stronger effects on bacterial communities than did glyphosate, which only explained 2 to 5% of the variation. Less than 1% of all taxa were impacted by glyphosate, more in soils with a long history of use, and more increased than decreased in relative abundance. Glyphosate had minimal impacts on soil and rhizosphere bacteria of wheat, although dying roots after glyphosate application may provide a "greenbridge" favoring some copiotrophic taxa. IMPORTANCE Glyphosate (Roundup) is the most widely used herbicide in the world and the foundation of Roundup Ready soybeans, corn, and the no-till cropping system. However, there have been recent concerns about nontarget impacts of glyphosate on soil microbes. Using next-generation sequencing methods and glyphosate treatments of wheat plants, we described the bacterial communities in the soil and rhizosphere of wheat grown in Pacific Northwest soils across multiple years, different locations, and soils with different histories of glyphosate use. The effects of glyphosate were subtle and much less than those of drivers such as location and cropping systems. Only a small percentage of the bacterial groups were influenced by glyphosate, and most of

Glyphosate Effects on Plant Mineral Nutrition, Crop Rhizosphere Microbiota, and Plant Disease in Glyphosate-Resistant Crops

Science.gov (United States)

2012-01-01

Claims have been made recently that glyphosate-resistant (GR) crops sometimes have mineral deficiencies and increased plant disease. This review evaluates the literature that is germane to these claims. Our conclusions are: (1) although there is conflicting literature on the effects of glyphosate on mineral nutrition on GR crops, most of the literature indicates that mineral nutrition in GR crops is not affected by either the GR trait or by application of glyphosate; (2) most of the available data support the view that neither the GR transgenes nor glyphosate use in GR crops increases crop disease; and (3) yield data on GR crops do not support the hypotheses that there are substantive mineral nutrition or disease problems that are specific to GR crops. PMID:23013354

Dissipation of glyphosate from grapevine soils in Sonora, Mexico

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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.

How glyphosate affects plant disease development: it is more than enhanced susceptibility.

Science.gov (United States)

Hammerschmidt, Ray

2018-05-01

Glyphosate has been shown to affect the development of plant disease in several ways. Plants utilize phenolic and other shikimic acid pathway-derived compounds as part of their defense against pathogens, and glyphosate inhibits the biosynthesis of these compounds via its mode of action. Several studies have shown a correlation between enhanced disease and suppression of phenolic compound production after glyphosate. Glyphosate-resistant crop plants have also been studied for changes in resistance as a result of carrying the glyphosate resistance trait. The evidence indicates that neither the resistance trait nor application of glyphosate to glyphosate-resistant plants increases susceptibility to disease. The only exceptions to this are cases where glyphosate has been shown to reduce rust diseases on glyphosate-resistant crops, supporting a fungicidal role for this chemical. Finally, glyphosate treatment of weeds or volunteer crops can cause a temporary increase in soil-borne pathogens that may result in disease development if crops are planted too soon after glyphosate application. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Effects of Zn, macronutrients, and their interactions through foliar applications on winter wheat grain nutritional quality.

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Shaoxia Wang

Full Text Available Although application of Zn combined with macronutrients (K, P, and N can be used to fortify wheat grain with Zn, little is known about their interactions when foliar application is employed or the influences of common soil fertility management practices (e.g. N and straw management on their efficiency. Therefore, the effects of foliar-applied Zn and N, P, or K on grain nutritional quality (especially Zn were investigated in wheat grown under different soil N rates at two sites with (Sanyuan or without (Yangling employing straw return. A 4-year-long field experiment was also conducted to evaluate the environmental stability of the foliar formulations. Across 6 site-years, foliar Zn application alone or combined with N, P, or K fertilizers resulted in 95.7%, 101%, 67.9% and 121% increases in grain Zn concentration, respectively. In terms of increasing grain Zn concentration, foliar-applied Zn positively interacted with N (at Sanyuan and K (at Yangling, but negatively interacted with P at any condition tested, suggesting depressive effects of foliarly-applied P on physiological availability of Zn. Although these interaction effects were the major factor that governing the efficiency of foliar-applied Zn combined with N, P, or K on grain Zn concentration, the magnitude of the increase/decrease in grain Zn (-3.96~5.71 mg kg-1 due to these interactions was much less than the average increases following Zn+K (31.3, Zn+P (18.7, and Zn+N (26.5 mg kg-1 treatments relative to that observed in foliar Zn-only treatment. The combined foliar application of Zn with N, P, or K did not cause any adverse impact on grain yield and other nutritional quality and in some cases slightly increased grain yield and macronutrient concentrations. Grain phytic acid:Zn molar ratios were respectively 52.0%, 53.1%, 43.4% and 63.5% lower in the foliar Zn, Zn+N, Zn+P and Zn+K treatments than in the control treatment. These effects were consistent over four years and across three

Effects of Zn, macronutrients, and their interactions through foliar applications on winter wheat grain nutritional quality.

Science.gov (United States)

Wang, Shaoxia; Li, Meng; Liu, Ke; Tian, Xiaohong; Li, Shuo; Chen, Yanlong; Jia, Zhou

2017-01-01

Although application of Zn combined with macronutrients (K, P, and N) can be used to fortify wheat grain with Zn, little is known about their interactions when foliar application is employed or the influences of common soil fertility management practices (e.g. N and straw management) on their efficiency. Therefore, the effects of foliar-applied Zn and N, P, or K on grain nutritional quality (especially Zn) were investigated in wheat grown under different soil N rates at two sites with (Sanyuan) or without (Yangling) employing straw return. A 4-year-long field experiment was also conducted to evaluate the environmental stability of the foliar formulations. Across 6 site-years, foliar Zn application alone or combined with N, P, or K fertilizers resulted in 95.7%, 101%, 67.9% and 121% increases in grain Zn concentration, respectively. In terms of increasing grain Zn concentration, foliar-applied Zn positively interacted with N (at Sanyuan) and K (at Yangling), but negatively interacted with P at any condition tested, suggesting depressive effects of foliarly-applied P on physiological availability of Zn. Although these interaction effects were the major factor that governing the efficiency of foliar-applied Zn combined with N, P, or K on grain Zn concentration, the magnitude of the increase/decrease in grain Zn (-3.96~5.71 mg kg-1) due to these interactions was much less than the average increases following Zn+K (31.3), Zn+P (18.7), and Zn+N (26.5 mg kg-1) treatments relative to that observed in foliar Zn-only treatment. The combined foliar application of Zn with N, P, or K did not cause any adverse impact on grain yield and other nutritional quality and in some cases slightly increased grain yield and macronutrient concentrations. Grain phytic acid:Zn molar ratios were respectively 52.0%, 53.1%, 43.4% and 63.5% lower in the foliar Zn, Zn+N, Zn+P and Zn+K treatments than in the control treatment. These effects were consistent over four years and across three soil N

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. ...

Comparative effects of glyphosate and atrazine in chloroplast ultrastructure of wheat and downy brome

International Nuclear Information System (INIS)

Auge, R.M.; Gealy, D.R.; Ogg, A.G.; Franceschi, V.R.

1987-01-01

Developing and mature leaves of winter wheat (Triticum aestivum L. var. Daws) and the weed species downy brome (Bromus tectorum L.) were subjected to 10 mM (foliar application) and 1 mM (root application) herbicide solutions. Glyphosate (N-(phosphonomethyl) glycine) and atrazine (2-chloro-4-(ethyl-amino)-6-(isopropylamino)-s-triazine) were prepared in a carrier composed of 5% soybean oil concentrate, 35% acetone and 60% water. Penetration experiments with 3 H-labelled herbicides assessed what percentage of herbicide entered leaves, and microautoradiography was used to determine qualitatively how much herbicide was present in the sections viewed with TEM. Tissue was excised at 4, 18, 62 and 200 hours, and then either freeze-substituted or fixed chemically. Ultrastructural effects of each herbicide on chloroplasts from leaves of newly-germinated seedlings and of well-tillered plants are depicted and discussed. Temporal differences in response of chloroplasts to each herbicide are noted

Effect of foliar nitrogen and sulphur application on aromatic expression of Vitis vinifera L. cv. Sauvignon blanc

Directory of Open Access Journals (Sweden)

Florian Lacroux

2008-09-01

Significance and impact of the study: Vine nitrogen deficiency can negatively impact on grape aroma potential. Soil nitrogen application can increase vine nitrogen status, but it has several drawbacks: it increases vigour and enhances Botrytis susceptibility. This study shows that foliar N and foliar N + S applications can improve vine nitrogen status and enhance aroma expression in Sauvignon blanc wines without the negative impact on vigour and Botrytis susceptibility. Although this study was carried out on Sauvignon blanc vines, it is likely that foliar N or foliar N + S applications will have similar effects on other grapevine varieties containing volatile thiols (Colombard, Riesling, Petit Manseng and Sémillon.

Effect of Nutrient Solution Concentration, Time and Frequency of Foliar Application on Growth of Leaf and Daughter Corms of Saffron (Crocus sativus L.

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R Khorasani

2015-07-01

Full Text Available In order to investigate the effect of different levels of nutrient solution concentration and times and frequencies of foliar applications on dry weight, nitrogen, phosphorus and potassium concentrations of leaf and corm of saffron, a pot experiment was conducted as a completely randomized design with factorial arrangement and three replications under open door conditions in research garden of ferdowsi university, faculty of agriculture. The experimental treatments were included 4 levels of solution concentration (0, 4, 8 and 12 per 1000 and 7 levels of time and frequency of foliar applications (F1: foliar application on 3th February, F2: foliar application on 18th February, F3: foliar application on 5th March, F4: foliar applications on 3th and 18th February, F5: foliar applications on 3th February and 5th March, F6: foliar applications on 18th February and 5th March, F7: foliar applications on 3th and 18th February and 5th March. Results of variance analysis showed that fresh and dry weight of corm and leaf were not influenced by concentration, time and frequency of foliar applications. Also, comparison of nitrogen, phosphorus and potassium concentrations of leaf and corm showed that there was no significant difference between levels of foliar treatments and control. Therefore, it seems that due attention to pattern of leaf and low nutrient demand of saffron, foliar applications in different levels of nutrient solution concentrations and times and frequencies of foliar applications could not increase vegetative growth and consequently, could not improve the growth and nutritional properties of saffron corms.

Improving hybrid seed production in corn with glyphosate-mediated male sterility.

Science.gov (United States)

Feng, Paul C C; Qi, Youlin; Chiu, Tommy; Stoecker, Martin A; Schuster, Christopher L; Johnson, Scott C; Fonseca, Augustine E; Huang, Jintai

2014-02-01

Hybrid corn varieties exhibit benefits associated with heterosis and account for most of the corn acreage in the USA. Hybrid seed corn is produced by crossing a female parent which is male-sterile and therefore incapable of self-pollination with a male parent as the pollen donor. The majority of hybrid seed corn is produced by mechanical detasseling which involves physically removing the tassel, a process that is laborious and costly. Glyphosate-resistant corn was developed via expression of a glyphosate insensitive 5-enolpyruvyl-shikimate 3-phosphate synthase enzyme (CP4-EPSPS). Experimentation with molecular expression elements resulted in selective reduction of CP4-EPSPS expression in male reproductive tissues. The resulting plant demonstrated sterile tassel following glyphosate application with little to no injury to the rest of the plant. Using (14)C-glyphosate as a marker, we also examined the translocation of glyphosate to the tassel via spray application in a track sprayer to simulate field application. The results allowed optimization of spray parameters such as dose, spray timing and target to maximize tassel delivery of glyphosate for efficient sterilization. The Roundup hybridization system (RHS) is a novel process for hybrid seed production based on glyphosate-mediated male sterility. RHS replaces mechanical detasseling with glyphosate spray and greatly simplifies the process of hybrid seed corn production. © 2013 Society of Chemical Industry.

The use of BMED for glyphosate recovery from glyphosate neutralization liquor in view of zero discharge.

Science.gov (United States)

Shen, Jiangnan; Huang, Jie; Liu, Lifen; Ye, Wenyuan; Lin, Jiuyang; Van der Bruggen, Bart

2013-09-15

Alkaline glyphosate neutralization liquors containing a high salinity pose a severe environmental pollution problem by the pesticide industry. However, there is a high potential for glyphosate recovery due to the high concentration of glyphosate in the neutralization liquors. In the study, a three-compartment bipolar membrane electrodialysis (BMED) process was applied on pilot scale for the recovery of glyphosate and the production of base/acid with high concentration in view of zero discharge of wastewater. The experimental results demonstrate that BMED can remove 99.0% of NaCl from the feed solution and transform this fraction into HCl and NaOH with high concentration and purity. This is recycled for the hydrolysis reaction of the intermediate product generated by the means of the Mannich reaction of paraformaldehyde, glycine and dimethylphosphite catalyzed by triethylamine in the presence of HCl and reclamation of the triethylamine catalyst during the production process of glyphosate. The recovery of glyphosate in the feed solution was over 96%, which is acceptable for industrial production. The current efficiency for producing NaOH with a concentration of 2.0 mol L(-1) is above 67% and the corresponding energy consumption is 2.97 kWh kg(-1) at a current density of 60 mA cm(-2). The current efficiency increases and energy consumption decreases as the current density decreases, to 87.13% and 2.37 kWh kg(-1), respectively, at a current density of 30 mA cm(-2). Thus, BMED has a high potential for desalination of glyphosate neutralization liquor and glyphosate recovery, aiming at zero discharge and resource recycling in industrial application. Copyright © 2013 Elsevier B.V. All rights reserved.

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)

Effect of foliar application of salicylic acid, hydrogen peroxide

Indian Academy of Sciences (India)

Home; Journals; Journal of Biosciences; Volume 42; Issue 2. Effect of foliar application of salicylic acid, hydrogen peroxide and a xyloglucan oligosaccharide on capsiate content and gene expression associatedwith capsinoids synthesis in Capsicum annuum L. AY ZUNUN-PÉREZ T GUEVARA-FIGUEROA SN ...

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

Directory of Open Access Journals (Sweden)

J.L. Pereira

2008-01-01

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

Interactions of glyphosate use with farm characteristics and cropping patterns in Central Europe.

Science.gov (United States)

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

2018-05-01

Although glyphosate is the most widely used herbicide in the European Union, little is known about the patterns of its usage in arable farming. Therefore, a nationwide survey of 2026 German farmers was analysed to obtain further knowledge about glyphosate applications in conventional European arable farming. Given its broad range of agri-environmental and farm-type conditions, Germany can be regarded as a suitable study region to represent Central European farming. The growing season 2013/2014 was set as a reference. Farmers who participated in the survey employ diverse patterns of glyphosate use. While 23% stated that they did not use glyphosate in the season in question, others applied glyphosate to their total arable area. However, most applications occurred on specific parts of the farm. Application patterns of oilseed rape, winter wheat, maize and sugar beet were studied in detail, and U-shaped distributions of glyphosate use intensity were observed. The effects of farm type and management practices on glyphosate use patterns were mixed in the various crops. Motivation for glyphosate use differs widely within the farming community. Agricultural researchers, extension services and policy makers are recommended to mitigate vulnerabilities associated with glyphosate use, such as routine spraying and practices that increase selection pressure for the evolution of glyphosate-resistant weeds. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

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.

The history and current status of glyphosate.

Science.gov (United States)

Duke, Stephen O

2018-05-01

Glyphosate is the only herbicide to target the enzyme 5-enolpyruvyl-3-shikimate phosphate synthase (EPSPS). It is a high use rate, non-selective herbicide that translocates primarily to metabolic sinks, killing meristematic tissues away from the application site. Its phloem-mobile properties and slow action in killing weeds allow the herbicide to move throughout the plant to kill all meristems, making it effective for perennial weed control. Since commercialization in 1974, its use has grown to dominate the herbicide market. Much of its use is on transgenic, glyphosate-resistant crops (GRCs), which have been the dominant transgenic crops worldwide. GRCs with glyphosate provided the most effective and inexpensive weed management technology in history for a decade or more. However, as a consequence of the rapid increase in glyphosate-resistant (GR) weeds, the effectiveness of glyphosate use in GRCs is declining. Critics have claimed that glyphosate-treated GRCs have altered mineral nutrition and increased susceptibility to plant pathogens because of glyphosate's ability to chelate divalent metal cations, but the complete resistance of GRCs to glyphosate indicates that chelating metal cations do not contribute to the herbicidal activity or significantly affect mineral nutrition. The rates of increases in yields of maize, soybean, and cotton in the USA have been unchanged after high adoption rates of GRCs. Glyphosate is toxic to some plant pathogens, and thereby can act as a fungicide in GRCs. Ultra-low doses of glyphosate stimulate plant growth in glyphosate-susceptible plants by unknown mechanisms. Despite rapid and widespread increases in GR weeds, glyphosate use has not decreased. However, as GR weeds increase, adoption of alternative technologies will eventually lead to decreased use. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. Published 2017. This article is a U.S. Government work and is in the public domain in

The effect of glyphosate application on soil microbial activities in ...

African Journals Online (AJOL)

In this study, glyphosate effects as N, P and C nutrient sources on microbial population and the effect of different concentration of it on dehydrogenease activity and soil respiration were investigated. The results show that in a soil with a long historical use of glyphosate (soil 1), the hetrotrophic bacterial population was ...

Identification of glyphosate resistance in Salsola tragus in north-eastern Oregon.

Science.gov (United States)

Barroso, Judit; Gourlie, Jennifer A; Lutcher, Larry K; Liu, Mingyang; Mallory-Smith, Carol A

2018-05-01

Farmers in the low-rainfall region of eastern Oregon rely on repeated applications of non-selective herbicides, predominately glyphosate, to control Salsola tragus in no-till fallow systems. Reports of poor glyphosate effectiveness have increased in recent years. Reduced efficacy is often attributed to dust, water stress, or generally poor growing conditions during application. Inadequate control also may be the result of the evolution of glyphosate resistance. Therefore, studies were undertaken to determine if glyphosate-resistant S. tragus populations occur in Oregon. Results from dose-response studies confirmed glyphosate resistance in three of 10 Oregon Salsola tragus populations. The ratio I 50R /I 50S from dose-response curves was, on average, 3.1 for the relative dry biomass per plant and 3.2 for the % of surviving plants per pot in these three populations. Plant mortality at recommended glyphosate doses for the resistant populations was less than 30% 3 weeks after treatment. Glyphosate resistance in S. tragus highlights the imperative need to diversify weed control strategies to preserve the longevity and sustainability of herbicides in semi-arid cropping systems of the Pacific Northwest. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Glyphosate

NARCIS (Netherlands)

A. Arcuri (Alessandra)

2017-01-01

markdownabstractGlyphosate is the rock star of pesticides, albeit a controversial one. With 6.1 billion kilograms applied globally in the last decade alone, it is the most widely used herbicide compound in the world. Glyphosate, is at the centre of an acrimonious controversy relating to whether the

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

Directory of Open Access Journals (Sweden)

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.

Recent advances in glyphosate biodegradation.

Science.gov (United States)

Zhan, Hui; Feng, Yanmei; Fan, Xinghui; Chen, Shaohua

2018-06-01

Glyphosate has emerged as the most widespread herbicide to control annual and perennial weeds. Massive use of glyphosate for decades has resulted in its ubiquitous presence in the environment, and poses a threat to humans and ecosystem. Different approaches such as adsorption, photocatalytic degradation, and microbial degradation have been studied to break down glyphosate in the environment. Among these, microbial degradation is the most effective and eco-friendly method. During its degradation, various microorganisms can use glyphosate as a sole source of phosphorus, carbon, and nitrogen. Major glyphosate degradation pathways and its metabolites have been frequently investigated, but the related enzymes and genes have been rarely studied. There are many reviews about the toxicity and fate of glyphosate and its major metabolite, aminomethylphosphonic acid. However, there is lack of reviews on biodegradation and bioremediation of glyphosate. The aims of this review are to summarize the microbial degradation of glyphosate and discuss the potential of glyphosate-degrading microorganisms to bioremediate glyphosate-contaminated environments. This review will provide an instructive direction to apply glyphosate-degrading microorganisms in the environment for bioremediation.

Effect of Foliar Application of Phosphorus and Water Deficit on Yield and Yield Components of Winter Wheat (Cultivar Alvand

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M. Vafapour

2011-04-01

Full Text Available In order to study the effects of foliar application of phosphorus (P and water deficit on yield and yield components of winter wheat (Triticum aestivum L., cv. Alvand, a split-plot experiment, with completely randomized blocks design and three replications, was carried out at the Research Farm of Boyer Ahmad Agricultural and Natural Resources Research Station, 13 km west of Yasouj, in 2008-2009. The main plots were irrigation at three levels (1- full irrigation (control, 2- deficit irrigation from the stem elongation to booting stage, and 3- deficit irrigation from booting stage to the end of growth period and the subplots were five levels of foliar application of P fertilizer (0, 3, 6, 9 and 12 kg/ha KH2PO4. The results showed that the effects of different irrigation regimes and foliar application of P were significant on all traits, and their interaction was significant on plant height, number of grain per spike, grain yield and biological yield. Full irrigation and foliar application of 6 kg/ha P produced the highest grain and biological yield (6000 and 14170 kg/ha, respectively and deficit irrigation from the stem elongation to booting stage without foliar application of P produced the lowest grain and biological yield (2920 and 8219 kg/ha, respectively. Foliar application of P affects significantly the evaluated traits only in drought-stress treatments and its effect was not significant in full irrigation treatment. In general, foliar application of 9 kg/ha P compensated the losses in wheat due to drought stress.

Aplicação foliar de fertilizantes organominerais em cultura de alface Foliar application of organic mineral fertilizer in lettuce

Directory of Open Access Journals (Sweden)

José Magno Q Luz

2010-09-01

Full Text Available A aplicação de fertilizantes organominerais tem permitido respostas positivas em diversas olerícolas. No presente trabalho avaliou-se a produção de mudas e produção comercial de alface, cultivar Vera, em função da aplicação foliar de fertilizantes organominerais líquidos, de outubro de 2005 a janeiro de 2006. A etapa de produção de mudas foi realizada em viveiro especializado na produção de mudas de hortaliças em Uberlândia e a condução da fase de campo foi realizada em área da Universidade Federal de Uberlândia. Analisou-se altura e número de folhas, massa fresca da parte aérea e diâmetro de raízes das mudas, massas fresca da parte aérea e de raízes das plantas na fase de campo. Foram empregados os fertilizantes organominerais Aminoagro Raiz, Aminoagro Folha Top, Aminoagro Mol, Nobrico Star, Aminolom Foliar e Lombrico Mol 75. O primeiro experimento utilizando mudas foi instalado em delineamento inteiramente casualizado com 15 repetições. O segundo experimento instalado a campo, foi feito em blocos ao acaso com 4 repetições. O uso exclusivo dos produtos organominerais líquidos, via aplicação foliar foi superior à testemunha para a maioria das variáveis avaliadas nas fases de muda e campo na alface, cultivar Vera.Biofertilizer application provides positive responses of several vegetable crops. The effect of foliar application of liquid biofertilizers on seedling and on commercial production of lettuce cultivar Vera were evaluated from October 2005 to January 2006. Seedling production was carried out in a nursery specialized in the production of vegetable seedlings, in Uberlandia, Minas Gerais State, Brazil, and the crop growing was carried out at a field of the Universidade Federal de Uberlandia. Plant height, number of leaves, aboveground part fresh weight and root diameter were evaluated on seedlings and fresh weight of the aboveground part and roots were evaluated on plants in the field. Aminoagro Raiz

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

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...

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

DEFF Research Database (Denmark)

Nørgaard, Trine; Møldrup, Per; Olsen, Preben

2013-01-01

applications in combination with the effect of precipitation events, drain water runoff, soil water content at 25 cm soil depth, management, and particle leaching patterns, and compares this with monitored field-scale glyphosate and AMPA leaching to a tile drainage system. Preliminary findings indicate...... that there is an accumulation of glyphosate and AMPA in the soil after the successive applications of glyphosate, as the level of the peaking concentrations right after applications increases. Furthermore, large precipitation events with subsequent high drain water runoff together with management, especially plowing...

Foliar nitrogen application in Cabernet Sauvignon vines: Effects on wine flavonoid and amino acid content.

Science.gov (United States)

Gutiérrez-Gamboa, Gastón; Garde-Cerdán, Teresa; Portu, Javier; Moreno-Simunovic, Yerko; Martínez-Gil, Ana M

2017-06-01

Wine quality greatly depends on its chemical composition. Among the most important wine chemical compounds, flavonoids are the major contributors to wine organoleptic properties while amino acids have a huge impact on fermentation development and wine volatile profile. Likewise, nitrogen applications are known to have an impact on wine composition. Therefore, the aim of this work was to study the effects of foliar nitrogen applications on wine flavonoid and amino acid composition. The experiment involved five foliar nitrogen applications at veraison time: urea (Ur), urea plus sulphur (Ur+S), arginine (Arg), and two commercial fertilizers Nutrimyr Thiols (NT) and Basfoliar Algae (BA). The results showed that nitrogen foliar treatments decreased wine flavonoid content although the effect varied according to each treatment. This could be related to a low vine nitrogen requirement, since must yeast assimilable nitrogen (YAN) was above acceptable threshold values for all samples. With regard to wine amino acid content, all treatments except for Ur increased its values after the applications. Finally, foliar nitrogen treatments greatly influenced wine composition. Among them, urea seemed to exert the most negative effect on both phenolics and amino acids. In addition, an inverse relationship between wine amino acid content and flavonol concentration was exhibited. Copyright © 2017. Published by Elsevier Ltd.

On glyphosate

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Tamas Komives

2016-11-01

Full Text Available This Editorial briefly discusses the current issues surrounding glyphosate - the most controversial pesticide active ingredient of our time. The paper pays special attention to the effects of glyphosate on plant-pathogen interactions.

Effects of Foliar Application of Nitrogen, Zinc and Manganese on Yield, Yield Components and Grain Quality of Chickpea in Two Growing Seasons

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B. Shirani

2015-09-01

Full Text Available To study the effects of foliar application of zinc, manganese and nitrogen on yield, yield components and grain quality of chickpea (Cicer arientinum L. two experiments, one in autumn and the other in spring were conducted at Research Farm, Shahrekord University in 2009-2010 growing season each as a randomized complete block design with three replications. The treatments were foliar application of zinc sulfate, manganese sulfate zinc sulfate and manganese sulfate mixture, nitrogen and distilled water (as control. The results showed that planting season had a significant effect on plant height, 100-seed weight and seed yield. All measured traits, except plant height, increased in winter compared to spring growing season. This increase was more than 12% for grain yield. Foliar application of nutrients significantly affected seed yield and seed yield components. Foliar application of nitrogen, presumably, through significant increase in number of pods per plant, number of seeds per plant and 100-seed weight, increased the grain yield by 6.2% compared to control. Foliar application × planting season interactions were significant for plant height and number of pods per plant. Foliar application of nitrogen caused a significant increase in grain yield and protein content. Foliar application of zinc sulphate significantly increased Zn content of grains however it did not affect seed yield. In conclusion, foliar application of nitrogen could be suggested for increasing protein and grain yield in chickpea under similar conditions to that of the present study.

Glyphosate, a chelating agent-relevant for ecological risk assessment?

Science.gov (United States)

Mertens, Martha; Höss, Sebastian; Neumann, Günter; Afzal, Joshua; Reichenbecher, Wolfram

2018-02-01

Glyphosate-based herbicides (GBHs), consisting of glyphosate and formulants, are the most frequently applied herbicides worldwide. The declared active ingredient glyphosate does not only inhibit the EPSPS but is also a chelating agent that binds macro- and micronutrients, essential for many plant processes and pathogen resistance. GBH treatment may thus impede uptake and availability of macro- and micronutrients in plants. The present study investigated whether this characteristic of glyphosate could contribute to adverse effects of GBH application in the environment and to human health. According to the results, it has not been fully elucidated whether the chelating activity of glyphosate contributes to the toxic effects on plants and potentially on plant-microorganism interactions, e.g., nitrogen fixation of leguminous plants. It is also still open whether the chelating property of glyphosate is involved in the toxic effects on organisms other than plants, described in many papers. By changing the availability of essential as well as toxic metals that are bound to soil particles, the herbicide might also impact soil life, although the occurrence of natural chelators with considerably higher chelating potentials makes an additional impact of glyphosate for most metals less likely. Further research should elucidate the role of glyphosate (and GBH) as a chelator, in particular, as this is a non-specific property potentially affecting many organisms and processes. In the process of reevaluation of glyphosate its chelating activity has hardly been discussed.

SE-ENRICHMENT OF CARROT AND ONION VIA FOLIAR APPLICATION

OpenAIRE

Kapolna, Emese; Laursen, Kristian H.; Hillestrøm, Peter; Husted, Søren; Larsen, Erik H.

2008-01-01

The aim of this work was to study the selenium accumulation in carrot and onion plants using foliar application by sodium selenite and sodium selenate. Furthermore, we aimed at identifying the Se species biosynthesised by onion and carrot plants. The results were used to prepare for production of 77Se enriched plants for an ongoing human absorption study.

The Effects Foliar Application of Methanol at Different Growth Stages on Kernel Related Traits in Chickpea var. ILC 482

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N. Naeimi,

2013-12-01

Full Text Available This research was conducted to evaluate the effects of foliar application of methanol on certain kernel related traits at different growth stages of pea var. ILC482 at the Research Station of Faculty of Agriculture in Islamic Azad University, Tabriz Branch in 2011. The study was conducted in split plot experiment based on Randomized Complete Block Design with three replications. Treatments were three levels methanol foliar application at different growth stages (vegetative, reproductive and foliar application at both two stages which considered as main factor, six levels of foliar application of methanol concentrations: (0 [control], 5, 10, 15, 20, 25, 30% as sub factor. Results showed that the interactions of methanol applications growth stages and its concentrations on grain number per plant, 100 kernel weight, grain yield, grain filing rate and harvest index were significantly different. Foliar application of methanol at reproductive stage decrease kernel related traits, but this application at both growth stages had positive effect on grain production and kernel related traits. This positive effect on number and 100 kernel weight were significant. The highest grain yield (2460 kg/ha was obtained by 20% concentration of methanol at both growth stages that increased grain yield above 13.5% compared to the control condition.

Foliar and soil application of 15N-labelled fertilizers in the cultivation of common bean and soybean

International Nuclear Information System (INIS)

Papanicolaou, E.P.; Skarlou, V.D.; Apostolakis, C.G.; Katranis, N.

1979-01-01

In two field experiments (one with beans and one with soybeans) during 1977, the influence of soil application of different nitrogen fertilizers and also of foliar application of the Hanway nutrient solution (N-P-K-S) on nitrogen fixation, grain yield and fertilizer utilization was studied. The nodule data for soybeans indicated that urea applied as starter, topdress or foliar spray adversely affected nodule number and weight. Starter (NH 4 ) 2 SO 4 had an effect similar to urea, while starter NH 4 NO 3 had slight or no adverse effect. Use of (NH 4 ) 2 SO 4 or NH 4 NO 3 in the Hanway solution had a strong adverse effect. Yield data of the soybean experiment indicated that urea, applied as starter or starter plus topdress, had no essential effect while foliar spray showed a clear adverse effect on the grain yield of soybean-nod. When (NH 4 ) 2 SO 4 or NH 4 NO 3 were used in the foliar spray, the adverse effect was more evident. Non-nod soybean showed slight yield response to topdress N and significant positive response to Hanway foliar spray. In the bean experiment some evidence of positive response to topdress N plus Hanway foliar spray was observed in the non-nod crop, but it was not significant. The utilization coefficient of the applied fertilizers varied with the treatments. The highest utilization coefficient (50-70%), for both experiments, was observed when urea was applied as foliar spray. Application of urea as starter gave low utilization while topdress application gave high utilization in the soybean experiment and low in that of common bean. Under the experimental conditions starter urea was better utilized than starter ammonium sulphate or nitrate. (author)

Glyphosate sustainability in South American cropping systems.

Science.gov (United States)

Christoffoleti, Pedro J; Galli, Antonio J B; Carvalho, Saul J P; Moreira, Murilo S; Nicolai, Marcelo; Foloni, Luiz L; Martins, Bianca A B; Ribeiro, Daniela N

2008-04-01

South America represents about 12% of the global land area, and Brazil roughly corresponds to 47% of that. The major sustainable agricultural system in South America is based on a no-tillage cropping system, which is a worldwide adopted agricultural conservation system. Societal benefits of conservation systems in agriculture include greater use of conservation tillage, which reduces soil erosion and associated loading of pesticides, nutrients and sediments into the environment. However, overreliance on glyphosate and simpler cropping systems has resulted in the selection of tolerant weed species through weed shifts (WSs) and evolution of herbicide-resistant weed (HRW) biotypes to glyphosate. It is a challenge in South America to design herbicide- and non-herbicide-based strategies that effectively delay and/or manage evolution of HRWs and WSs to weeds tolerant to glyphosate in cropping systems based on recurrent glyphosate application, such as those used with glyphosate-resistant soybeans. The objectives of this paper are (i) to provide an overview of some factors that influence WSs and HRWs to glyphosate in South America, especially in Brazil, Argentina and Paraguay soybean cropped areas; (ii) to discuss the viability of using crop rotation and/or cover crops that might be integrated with forage crops in an economically and environmentally sustainable system; and (iii) to summarize the results of a survey of the perceptions of Brazilian farmers to problems with WSs and HRWs to glyphosate, and the level of adoption of good agricultural practices in order to prevent or manage it. Copyright (c) 2008 Society of Chemical Industry.

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

2011-06-08

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.

Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate.

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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

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

Glyphosate Use and Cancer Incidence in the Agricultural Health Study.

Science.gov (United States)

Andreotti, Gabriella; Koutros, Stella; Hofmann, Jonathan N; Sandler, Dale P; Lubin, Jay H; Lynch, Charles F; Lerro, Catherine C; De Roos, Anneclaire J; Parks, Christine G; Alavanja, Michael C; Silverman, Debra T; Beane Freeman, Laura E

2018-05-01

Glyphosate is the most commonly used herbicide worldwide, with both residential and agricultural uses. In 2015, the International Agency for Research on Cancer classified glyphosate as "probably carcinogenic to humans," noting strong mechanistic evidence and positive associations for non-Hodgkin lymphoma (NHL) in some epidemiologic studies. A previous evaluation in the Agricultural Health Study (AHS) with follow-up through 2001 found no statistically significant associations with glyphosate use and cancer at any site. The AHS is a prospective cohort of licensed pesticide applicators from North Carolina and Iowa. Here, we updated the previous evaluation of glyphosate with cancer incidence from registry linkages through 2012 (North Carolina)/2013 (Iowa). Lifetime days and intensity-weighted lifetime days of glyphosate use were based on self-reported information from enrollment (1993-1997) and follow-up questionnaires (1999-2005). We estimated incidence rate ratios (RRs) and 95% confidence intervals (CIs) using Poisson regression, controlling for potential confounders, including use of other pesticides. All statistical tests were two-sided. Among 54 251 applicators, 44 932 (82.8%) used glyphosate, including 5779 incident cancer cases (79.3% of all cases). In unlagged analyses, glyphosate was not statistically significantly associated with cancer at any site. However, among applicators in the highest exposure quartile, there was an increased risk of acute myeloid leukemia (AML) compared with never users (RR = 2.44, 95% CI = 0.94 to 6.32, Ptrend = .11), though this association was not statistically significant. Results for AML were similar with a five-year (RRQuartile 4 = 2.32, 95% CI = 0.98 to 5.51, Ptrend = .07) and 20-year exposure lag (RRTertile 3 = 2.04, 95% CI = 1.05 to 3.97, Ptrend = .04). In this large, prospective cohort study, no association was apparent between glyphosate and any solid tumors or lymphoid malignancies overall, including NHL and

Residual effect of sugar cane ratoon of urea nitrogen foliar application to plant cane

International Nuclear Information System (INIS)

Trivelin, P.C.O.; Lara Cabezas, W.A.R.; Coleti, J.T.

1984-01-01

The residual effect of urea - N, foliar applied to plant cane, on sugar cane ratoon is studied. Setts grown in drums containing washed sand are used. 180 days from planting, foliar fertilizer (43.5% urea solution) labelled with 3.95 atom % 15 N is applied. The first harvest is made 7 days after application and final harvest of resprouting at 123 days. (M.A.C.) [pt

Impact of Potassium Foliar Application in Alleviating the Harmful Effects of Salinity in Spinach

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Amirhooshang jalali

2017-02-01

Full Text Available Introduction: Spinach is an important leafy vegetable in the cold season, and despite the fact that is considered as low-calorie food source contains significant amount of minerals such as iron, and vitamin A and C. According to the University of Utah 3.8 dS m-1 is salinity tolerance threshold for the spinach and yield decrease that have been reported by 10%, 25% and 50% at 5.5, 7 and 8 dS m-1 salinity. The necessity to supply adequate potassium has been demonstrated in salinity conditions. In salt stress conditions, foliar application of K in spinach, reduces the harmful effects of salt and increase the ratio of potassium to sodium (1.61 to 2.72. Foliar application of K with prevent of potassium transfer from root to shoot is causing continuation of photosynthesis and reduce the effects of salinity. Absorption of potassium from the leaves depends on the type of used compound. In this context, characteristics of plant (leaves with a waxy composition, duration of growth and leaf area are important. 100 kg ha-1 of potassium in salt stress conditions by reducing the absorption of sodium, increased salt tolerance on the sunflower. Materials and Methods: In order to evaluate the foliar application of K on the yield and yield components of spinach in salt stress condition, a study was conducted in 2012 by using split plot randomized based on complete block design with four replications at Isfahan Agricultural and Natural Resources Research Station. Three levels of irrigation water salinity consisted of a control (2 dS m-1, well water with salinity (4 dS m-1 and well water with salinity (8dS m-1 arranged in main plots and two levels of control and foliar applications of potassium fertilizer containing potassium oxide solubility in water (2.5 ml per liter arranged in subplots. Statistical analysis was conducted by using SAS software and statistical tests were compared with Duncan at 5 percent. Result and Discussions: The results showed that the yield of

DISPERSION OF GLYPHOSATE IN SOILS UNDERGOING EROSION

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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

Uses of glyphosate in German arable farming – operational aspects

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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.

Effect of formulations on the absorption and translocation of glyphosate in transgenic soybean

International Nuclear Information System (INIS)

Santos, J.B.; Ferreira, E.A.; Silva, A.A.; Oliveira, J.A.; Fialho, C.M.T.

2007-01-01

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)

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.

Foliar absorption of 15N labeled urea by tea plant

International Nuclear Information System (INIS)

Hoshina, Tsuguo; Kozai, Shuji; Ishigaki, Kozo

1978-01-01

The effect of foliar application on the nitrogen nutrient status of tea shoots has been studied using 15 N labelled urea. Furthermore, the difference in nitrogen utilization by tea plant between foliar applied and top dressed nitrogen was investigated using 15 N labelled urea and ammonium sulfate. The foliar application of urea increased the amount of chlorophyll and total nitrogen in the new shoot, and the foliar application was more effective under shading condition. The urea sprayed upon old leaves prior to the opening of new leaf translocated to the new shoots. However, the foliar application after the opening of new leaf was more effective on nitrogen absorption by new shoots than one prior to that, and rather than top dressing for new shoots. It could be recognized that the foliar application of urea raises the nitrogen nutrient status of tea leaves in summer. (author)

Foliar K application delays leaf senescence of winter rape-seed (Brassica napus L.) under waterlogging

Institute of Scientific and Technical Information of China (English)

Lin Wan; Chao Hu; Chang Chen; Liyan Zhang; Ni Ma; Chunlei Zhang

2017-01-01

To better understand waterlogging effect on leaf senescence in winter rapseed (Brassica napus L.) during flowering stage, experiments were designed to explore foliar K application influences on adverse effects of waterlogging stress. Winter rapeseed was sprayed with K after waterlogging at initial flowering stage. Results indicated that waterlog-ging significantly decreased leaf net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci) and transpiration rate (Tr). It also declined maximum quantum yield of PS II (Fv/Fm), quantum yield of electron transport (ΦPS II) and pho-tochemical quenching (qP), but increased leaf non-photochemical quenching (NPQ) and minimal fluorescence (Fo). Interestingly, exogenous application of K significantly alleviated waterlogging-induced photosynthesis inhibition. Foliar K application increased RuBisCO activation, chlorophyll and soluble protein contents, while significantly decreased MDA con-tent under waterlogging stress. Moreover, K supplementation improved accumulation of K+, Ca2+, Mg2+, N, Zn2+, Mn2+, Fe2+ in leaves. In general, foliar K application is effective in alleviating deleterious effects of waterlogging stress and delays leaf senescence of winter rapeseed.

Molecular basis of glyphosate resistance: Different approaches through protein engineering

Science.gov (United States)

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-resistant plants were introduced thus allowing the application of the herbicide to the crop (post-emergence) to remove emerged weeds without crop damage. This review focuses on the evolution of 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 rationale for the means by which the modifications made have had their intended effect. PMID:21668647

Glyphosate resistance: state of knowledge

Science.gov (United States)

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 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. PMID:25180399

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-...

Effects of soil and foliar applications of iron and zinc on flowering and essential oil of chamomile at greenhouse conditions

Directory of Open Access Journals (Sweden)

Yousef NASIRI

2015-11-01

Full Text Available In order to study the effects of soil and foliar applications of iron (Fe and zinc (Zn on flowering, flower yield and essential oil production of German chamomile a pot experiment was conducted under greenhouse conditions at the Faculty of Agriculture, University of Tabriz, Iran in 2012. The experiment was arranged as completely randomized design with 12 treatments and three replications. Treatments were as follow: T1: control – without Fe or Zn fertilizers, T2: 30 mg FeSO4.7H2O kg-1 dry soil, T3: 22 mg ZnSO4.7H2O kg-1 dry soil, T4: 30 mg FeSO4.7H2O + 22 mg ZnSO4.7H2O kg-1 dry soil, T5: foliar spraying of FeSO4.7H2O (3.5 g L-1, T6: foliar spraying of FeSO4.7H2O (7.0 g L-1, T7: foliar spraying of ZnSO4.7H2O (2.5 g L-1, T8: foliar spraying of ZnSO4.7H2O (5.0 g L-1, T9: T5+T7, T10: T5+T8, T11: T6+T7, T12: T6+T8. The foliar spraying was done two times during the growing period. The results revealed that the flower number, flower yield, essential oil content and essential oil yield were significantly increased by soil and foliar applications of Fe + Zn, compared with the control (untreated. The highest flower number (477 plant-1, flower yield (11.6 g pot-1, essential oil content (0.88 % and essential oil yield (119 mg pot-1 were recorded for the soil application of Fe + Zn (T4 by 58, 68, 21.4 and 105 % increment compared to the control, respectively. Foliar application of Fe + Zn (T12 was placed at the next rank; however this treatment had no significant difference with the soil application of Fe + Zn (T4. Other treatments did not show significant differences with the control. Generally, the results showed that soil or foliar application of Fe + Zn can be effective on increase or improve of quantity and quality of chamomile yield. Moreover, use of foliar application as a low cost method especially in areas with alkaline or calcareous soils can be recommended.

Aldo-keto reductase enzymes detoxify glyphosate and improve herbicide resistance in plants.

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Vemanna, Ramu S; Vennapusa, Amaranatha Reddy; Easwaran, Murugesh; Chandrashekar, Babitha K; Rao, Hanumantha; Ghanti, Kirankumar; Sudhakar, Chinta; Mysore, Kirankumar S; Makarla, Udayakumar

2017-07-01

In recent years, concerns about the use of glyphosate-resistant crops have increased because of glyphosate residual levels in plants and development of herbicide-resistant weeds. In spite of identifying glyphosate-detoxifying genes from microorganisms, the plant mechanism to detoxify glyphosate has not been studied. We characterized an aldo-keto reductase gene from Pseudomonas (PsAKR1) and rice (OsAKR1) and showed, by docking studies, both PsAKR1 and OsAKR1 can efficiently bind to glyphosate. Silencing AKR1 homologues in rice and Nicotiana benthamiana or mutation of AKR1 in yeast and Arabidopsis showed increased sensitivity to glyphosate. External application of AKR proteins rescued glyphosate-mediated cucumber seedling growth inhibition. Regeneration of tobacco transgenic lines expressing PsAKR1 or OsAKRI on glyphosate suggests that AKR can be used as selectable marker to develop transgenic crops. PsAKR1- or OsAKRI-expressing tobacco and rice transgenic plants showed improved tolerance to glyphosate with reduced accumulation of shikimic acid without affecting the normal photosynthetic rates. These results suggested that AKR1 when overexpressed detoxifies glyphosate in planta. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Physiological and Biochemical Responses of Lavandula angustifolia to Salinity Under Mineral Foliar Application

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Chrysargyris, Antonios; Michailidi, Evgenia; Tzortzakis, Nikos

2018-01-01

Saline water has been proposed as a solution to partially cover plant water demands due to scarcity of irrigation water in hot arid areas. Lavender (Lavandula angustifolia Mill.) plants were grown hydroponically under salinity (0–25–50–100 mM NaCl). The overcome of salinity stress was examined by K, Zn, and Si foliar application for the plant physiological and biochemical characteristics. The present study indicated that high (100 mM NaCl) salinity decreased plant growth, content of phenolics and antioxidant status and essential oil (EO) yield, while low-moderate salinity levels maintained the volatile oil profile in lavender. The integrated foliar application of K and Zn lighten the presumable detrimental effects of salinity in terms of fresh biomass, antioxidant capacity, and EO yield. Moderate salinity stress along with balanced concentration of K though foliar application changed the primary metabolites pathways in favor of major volatile oil constituents biosynthesis and therefore lavender plant has the potential for cultivation under prevalent semi-saline conditions. Zn and Si application, had lesser effects on the content of EO constituents, even though altered salinity induced changings. Our results have demonstrated that lavender growth/development and EO production may be affected by saline levels, whereas mechanisms for alteration of induced stress are of great significance considering the importance of the oil composition, as well. PMID:29731759

Effect of Nitrogen Foliar Application on Canola Yield (Brassica napus L. and Nitrogen Efficiency across Different Sowing Dates

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S Doori

2016-12-01

Full Text Available Introduction Between oil seeds, from the quality, quantity and nutrition index point of view, canola has the top level . Because of the solubility of N fertilizers, the time of urea application, is very important and one of the main reasons of the reduction in N application efficiency is utilization of urea in an inappropriate time. By precisely foliar application of nitrogen, the efficiency of nitrogen transformation to the grain will be very high because in this method the leaf is considered the main organ of nitrogen uptake and a low amount of absorbed nitrogen was transferred to the root and entered the soil. The more division of N application in growth stages and in accordance with plant need and foliar application result in increasing nitrogen use efficiency. The delay in sowing will result in the reduction of yield and this is due to low LAI, and thus low radiation absorb in vegetable phase and shorter reproductive phase with high temperature in flowering and subsequent stages that result in low prolific silique and make disorder in transferring stored material to grain. In this experiment using N foliar application to decrease the adverse effect of delay in sowing is objective. Materials and Methods The experiment was conducted in 2013-2014 in Ramin Agriculture and Natural Resource University of Khuzestan. Experiment was conducted as split plots in a randomized complete blocks design with three replications. In this experiment sowing date]optimum sowing (27 November, 17 December and late sowing (30 December [were assigned to main plots and several time of N-foliar application with 5 percent density from urea (20 liter per ha, ]TO (control, T1 (foliar N application in rosette stage, T2 (foliar N application in budding stage, T3 (foliar N application in flowering stage[ were placed in sub-plots in randomized way. Fertilizing was based on the results of soil examination. Therefore, 162 kg ha-1 of pure nitrogen (from resource urea in the way

Glyphosate and Roundup® alter morphology and behavior in zebrafish.

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Bridi, Daiane; Altenhofen, Stefani; Gonzalez, Jonas Brum; Reolon, Gustavo Kellermann; Bonan, Carla Denise

2017-12-01

Glyphosate has become the most widely used herbicide in the world, due to the wide scale adoption of transgenic glyphosate resistant crops after its introduction in 1996. Glyphosate may be used alone, but it is commonly applied as an active ingredient of the herbicide Roundup ® . This pesticide contains several adjuvants, which may promote an unknown toxicity. The indiscriminate application poses numerous problems, both for the health of the applicators and consumers, and for the environment, contaminating the soil, water and leading to the death of plants and animals. Zebrafish (Danio rerio) is quickly gaining popularity in behavioral research, because of physiological similarity to mammals, sensitivity to pharmacological factors, robust performance, low cost, short spawning intervals, external fertilization, transparency of embryos through larval stages, and rapid development. The aim of this study was evaluate the effects of glyphosate and Roundup ® on behavioral and morphological parameters in zebrafish larvae and adults. Zebrafish larvae at 3days post-fertilization and adults were exposed to glyphosate (0.01, 0.065, and 0.5mg/L) or Roundup ® (0.01, 0.065, and 0.5mg/L) for 96h. Immediately after the exposure, we performed the analysis of locomotor activity, aversive behavior, and morphology for the larvae and exploratory behavior, aggression and inhibitory avoidance memory for adult zebrafish. In zebrafish larvae, there were significant differences in the locomotor activity and aversive behavior after glyphosate or Roundup ® exposure when compared to the control group. Our findings demonstrated that exposure to glyphosate at the concentration of 0.5mg/L, Roundup ® at 0.065 or 0.5mg/L reduced the distance traveled, the mean speed and the line crossings in adult zebrafish. A decreased ocular distance was observed for larvae exposed at 0.5mg/L of glyphosate. We verified that at 0.5mg/L of Roundup ® -treated adult zebrafish demonstrated a significant

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

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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.

Correlation of leaf damage with uptake and translocation of glyphosate in velvetleaf (Abutilon theophrasti)

International Nuclear Information System (INIS)

Feng, P.C.C.; Ryerse, J.S.; Sammons, R.D.

1998-01-01

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)

Identifying Chloris Species from Cuban Citrus Orchards and Determining Their Glyphosate-Resistance Status

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Enzo R. Bracamonte

2017-11-01

Full Text Available The Chloris genus is a C4 photosynthetic species mainly distributed in tropical and subtropical regions. Populations of three Chloris species occurring in citrus orchards from central Cuba, under long history glyphosate-based weed management, were studied for glyphosate-resistant status by characterizing their herbicide resistance/tolerance mechanisms. Morphological and molecular analyses allowed these species to be identified as C. ciliata Sw., Chloris elata Desv., and Chloris barbata Sw. Based on the glyphosate rate that causes 50% mortality of the treated plants, glyphosate resistance (R was confirmed only in C. elata, The R population was 6.1-fold more resistant compared to the susceptible (S population. In addition, R plants of C. elata accumulated 4.6-fold less shikimate after glyphosate application than S plants. Meanwhile, populations of C. barbata and C. ciliata with or without glyphosate application histories showed similar LD50 values and shikimic acid accumulation rates, demonstrating that resistance to glyphosate have not evolved in these species. Plants of R and S populations of C. elata differed in 14C-glyphosate absorption and translocation. The R population exhibited 27.3-fold greater 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS activity than the S population due to a target site mutation corresponding to a Pro-106-Ser substitution found in the EPSPS gene. These reports show the innate tolerance to glyphosate of C. barbata and C. ciliata, and confirm the resistance of C. elata to this herbicide, showing that both non-target site and target-site mechanisms are involved in its resistance to glyphosate. This is the first case of herbicide resistance in Cuba.

Effects of EPSPS Copy Number Variation (CNV and Glyphosate Application on the Aromatic and Branched Chain Amino Acid Synthesis Pathways in Amaranthus palmeri

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Manuel Fernández-Escalada

2017-11-01

Full Text Available A key enzyme of the shikimate pathway, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19, is the known target of the widely used herbicide glyphosate. Glyphosate resistance in Amaranthus palmeri, one of the most troublesome weeds in agriculture, has evolved through increased EPSPS gene copy number. The aim of this work was to study the pleiotropic effects of (i EPSPS increased transcript abundance due to gene copy number variation (CNV and of (ii glyphosate application on the aromatic amino acid (AAA and branched chain amino acid (BCAA synthesis pathways. Hydroponically grown glyphosate sensitive (GS and glyphosate resistant (GR plants were treated with glyphosate 3 days after treatment. In absence of glyphosate treatment, high EPSPS gene copy number had only a subtle effect on transcriptional regulation of AAA and BCAA pathway genes. In contrast, glyphosate treatment provoked a general accumulation of the transcripts corresponding to genes of the AAA pathway leading to synthesis of chorismate in both GS and GR. After chorismate, anthranilate synthase transcript abundance was higher while chorismate mutase transcription showed a small decrease in GR and remained stable in GS, suggesting a regulatory branch point in the pathway that favors synthesis toward tryptophan over phenylalanine and tyrosine after glyphosate treatment. This was confirmed by studying enzyme activities in vitro and amino acid analysis. Importantly, this upregulation was glyphosate dose dependent and was observed similarly in both GS and GR populations. Glyphosate treatment also had a slight effect on the expression of BCAA genes but no general effect on the pathway could be observed. Taken together, our observations suggest that the high CNV of EPSPS in A. palmeri GR populations has no major pleiotropic effect on the expression of AAA biosynthetic genes, even in response to glyphosate treatment. This finding supports the idea that the fitness cost associated

Formulants of glyphosate-based herbicides have more deleterious impact than glyphosate on TM4 Sertoli cells.

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Vanlaeys, Alison; Dubuisson, Florine; Seralini, Gilles-Eric; Travert, Carine

2018-05-15

Roundup and Glyphogan are glyphosate-based herbicides containing the same concentration of glyphosate and confidential formulants. Formulants are declared as inert diluents but some are more toxic than glyphosate, such as the family of polyethoxylated alkylamines (POEA). We tested glyphosate alone, glyphosate-based herbicide formulations and POEA on the immature mouse Sertoli cell line (TM4), at concentrations ranging from environmental to agricultural-use levels. Our results show that formulations of glyphosate-based herbicides induce TM4 mitochondrial dysfunction (like glyphosate, but to a lesser extent), disruption of cell detoxification systems, lipid droplet accumulation and mortality at sub-agricultural doses. Formulants, especially those present in Glyphogan, are more deleterious than glyphosate and thus should be considered as active principles of these pesticides. Lipid droplet accumulation after acute exposure to POEA suggests the rapid penetration and accumulation of formulants, leading to mortality after 24 h. As Sertoli cells are essential for testicular development and normal onset of spermatogenesis, disturbance of their function by glyphosate-based herbicides could contribute to disruption of reproductive function demonstrated in mammals exposed to these pesticides at a prepubertal stage of development. Copyright © 2017. Published by Elsevier Ltd.

Effects of the herbicide glyphosate on non-target plant native species from Chaco forest (Argentina).

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Florencia, Ferreira María; Carolina, Torres; Enzo, Bracamonte; Leonardo, Galetto

2017-10-01

Agriculture based on transgenic crops has expanded in Argentina into areas formerly occupied by Chaco forest. Even though glyphosate is the herbicide most widely used in the world, increasing evidence indicates severe ecotoxicological effects on non-target organisms as native plants. The aim of this work is to determine glyphosate effects on 23 native species present in the remaining Chaco forests immersed in agricultural matrices. This is a laboratory/greenhouse approach studying acute effects on seedlings after 21 days. A gradient of glyphosate rates (525, 1050, 2100, 4200, and 8400g ai/Ha; recommended field application rate (RFAR) = 2100g ai/Ha) was applied on four-week seedlings cultivated in a greenhouse and response variables (phytotoxicity, growth reduction, and sensitivity to the herbicide) were measured. This gradient of herbicide rates covers realistic rates of glyphosate applications in the crop field and also those that can reach vegetation of forest relicts by off-target drift and overspray. Testing was performed following guidelines for vegetative vigour (post-germination spray). All species showed lethal or sublethal effects after the application of the 25% of RFAR (50% of species showed severe phytotoxicity or death and 70% of species showed growth reduction). The results showed a gradient of sensitivity to glyphosate by which some of the studied species are very sensitive to glyphosate and seedlings died with 25% of RFAR while other species can be classified as herbicide-tolerant. Thus, the vegetation present in the forest relicts could be strongly affected by glyphosate application on crops. Lethal and sublethal effects of glyphosate on non-target plants could promote both the loss of biodiversity in native forest relicts immersed in the agroecosystems and the selection of new crop weeds considering that some biotypes are continuously exposed to low doses of glyphosate. Copyright © 2017 Elsevier Inc. All rights reserved.

Glyphosate

OpenAIRE

Arcuri, Alessandra

2017-01-01

markdownabstractGlyphosate is the rock star of pesticides, albeit a controversial one. With 6.1 billion kilograms applied globally in the last decade alone, it is the most widely used herbicide compound in the world. Glyphosate, is at the centre of an acrimonious controversy relating to whether the substance is carcinogenic to humans and toxic for the environment. The controversy took a sharp legal turn when, in March 2015, the International Agency for Research on Cancer (IARC), which is the ...

Improvement of growth and productivity of cotton (Gossypium hirsutum L. through foliar applications of naphthalene acetic acid

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Shazia Parveen

2017-05-01

Full Text Available Plant growth regulators like naphthalene acetic acid (NAA positively affect the growth and yield of crop plants. An experiment was conducted to check the foliar application of NAA on growth and yield components of cotton variety Bt.121 under field condition at research area of agriculture farm near Cholistan Institute of Desert Studies (CIDS, The Islamia University of Bahawalpur, Pakistan. The experiment was comprised of foliar application of NAA (1% viz. T0 (control, T1 (One spray of NAA, T2 (Two sprays of NAA, T3 (Three sprays of NAA, T4 (Four sprays of NAA. The first foliar spray was applied at 45 days after sowing (DAS and later on it was continued with 15 days interval with skilled labour by hand pump sprayer. The experiment was laid out in randomized complete block design and each treatment was replicated three times. Data recorded on growth, chlorophyll contents, yield and yield components showed a significant increase with the application of NAA. Furthermore, earliness index, mean maturity date and production rate index were also influenced with foliar application of NAA. On the basis of growth and yield parameters it can be concluded that four spray of NAA (1% can be applied commercially under field conditions.

Concentração foliar de manganês e zinco em laranjeiras adubadas com óxidos e carbonatos via foliar Leaf concentrations of manganese and zinc in the orange fertilized via foliar application with oxides and carbonates

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Leandro José Grava de Godoy

2013-09-01

Full Text Available Dentre os micronutrientes, o Zn e o Mn limitam a produção dos citros, no Brasil. A aplicação foliar tem sido a forma tradicional de fornecimento, contudo, a eficiência desta adubação depende de uma série de fatores, entre eles o tipo de fertilizante. Foram realizados dois experimentos em pomar com laranjeiras Pêra, enxertadas em limão cravo, com sete anos de idade, em Botucatu, SP. No primeiro experimento foram avaliadas três fontes de Mn via foliar: carbonato de manganês A, carbonato de manganês B e sulfato manganoso, em duas doses para cada fertilizante, correspondente a 250 e 500 g ha-1 de Mn, mais o controle, pulverizado somente com água. No segundo experimento foram testadas três fontes de Zn para aplicação foliar: óxido de zinco A, óxido de zinco B e sulfato de zinco, em duas doses para cada fertilizante, correspondente a 375 e 750 g ha-1 de Zn, mais o controle. As amostragens de folhas foram realizadas mensalmente, iniciando aos 30 dias após aplicação dos tratamentos. A aplicação foliar com carbonato de manganês B, na dose de 500 g ha-1 Mn, e com óxido de zinco B, na dose de 750 g ha-1, proporcionaram, respectivamente, níveis nutricionais adequados de Mn e Zn nas folhas de laranjeira. Na ausência de chuvas, os teores adequados de Mn e Zn no solo, não permitem suprir satisfatoriamente as laranjeiras Pêra enxertadas em limoeiro cravo.Among micronutrients, Zn and Mn limit the production of citrus in Brazil. Foliar application has been the traditional form of supply, however the efficiency of this type of fertilization depends on a number of factors, including the type of fertilizer used. Two experiments were conducted in an orchard of seven year old Pêra orange, grafted onto Rangpur lime, in Botucatu, São Paulo. In the first experiment three sources of Mn, applied via foliar application, were evaluated: manganese carbonate A, manganese carbonate B and manganese sulphate, at two rates per fertilizer

Competition between rice (Oryza sativa L.) and (barnyardgrass (Echinochloa crus-galli (L.) P. Beauv.) as affected by methanol foliar application.

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Rezaeieh, Alireza D; Aminpanah, Hashem; Sadeghi, Seyed M

2015-01-01

Pot experiment was conducted in Iran, to evaluate the effect of methanol on competition between rice (Oryza sativa) and barnyardgrass (Echinochloa crus-galli). The experiment was conducted as a randomized complete block design with a factorial treatment arrangement and three replicates. Factors were two aqueous methanol foliar applications (0, and 14% v/v) and five rice: barnyardgrass ratios (100:0, 75:25, 50:50, 25:6, and 0:100). Replacement series diagrams for aboveground dry weight illustrated that 'Shiroudi' was more competitive than barnyardgrass as averaged across methanol foliar applications. When methanol was not sprayed, the lines for 'Shiroudi' and barnyardgrass intersected at 75:25 rice: barnyardgrass ratio, but when methanol was sprayed at 14% v/v, the lines for 'Shiroudi' and barnyardgrass intersect at the left of the 75:25 rice: barnyardgrass mixture proportion. These indicate that methanol application reduced competitive ability of 'Shiroudi' against barnyardgrass for aboveground biomass accumulation. At the same time, Methanol foliar application significantly reduced the relative crowding coefficient of 'Shiroudi' while simultaneously it significantly increased the relative crowding coefficient of barnyard grass. This indicates that methanol foliar application reduced the competitive ability of 'Shiroudi' against barnyardgrass for shoot biomass accumulation. This experiment illustrated that foliar spray of aqueous methanol can not be recommended for rice under weedy conditions.

Resposta de diferentes populações de Digitaria insularis ao herbicida glyphosate Response of different Digitaria insularis populations to glyphosate

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N.M Correia

2010-12-01

, research and production farm of UNESP, Jaboticabal-SP; a grain production area located in the agricultural area of Campo Florido, MG, and Rio Verde, GO; citrus production area located in the agricultural area of Matão, SP, and an area without previous glyphosate application (Jaboticabal-SP. Glyphosate (0D, 1/4D, 1/2D, D, 2D, 4D and 8D, where D is the recommended rate of 1.5 kg ha-1 of acid equivalent and its associations [glyphosate plus fluazifop-p-butyl (1.5 plus 0.25 kg ha-1 and glyphosate (1.5 kg ha-1 in sequence with diuron plus paraquat (0.20 plus 0.40 kg ha-1 plus 0.2% of surfactant] were sprayed on the 7-8 tiller plants with average height of 20 cm. Campo Florido, MG and Rio Verde, GO sourgrass populations were considered susceptible; those of Jaboticabal-SP and Matão,SP were found to be tolerant and those from the nonagricultural area were considered of intermediate sensitivity. The association of glyphosate with fluazifop, or its application in sequence with diuron plus paraquat, were efficient in the control of sourgrass tolerant populations.

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.

[Poisonings with the herbicides glyphosate and glyphosate-trimesium].

Science.gov (United States)

Mortensen, O S; Sørensen, F W; Gregersen, M; Jensen, K

2000-08-28

Generally the herbicide glyphosate is considered harmless to humans. Glyphosate-trimesium is labelled harmful (Xn), whereas glyphosate-isopropylamine carries no warning sign. As cases of serious poisoning have emerged contacts to the Poison Information Centre have been reviewed. The persons exposed were mainly smaller children and adults 20 to 59 years of age. Oral exposure was recorded in 47 persons, inhalation exposure in 24 and topical contact in 42. About one fourth of the exposed persons were asymptomatic. Most of the symptomatic poisonings demonstrated complaints from the mouth, the gastrointestinal tract and the airways. Eleven patients were admitted to hospital. Two died, one of them having ingested the isopropylamine salt, the other the trimesium salt. Death ensued quickly in the latter patient. A similar fate was observed in a child--not included in the present material--who had also ingested the trimesium compound.

Physiological responses of Tillandsia albida (Bromeliaceae) to long-term foliar metal application

International Nuclear Information System (INIS)

Kováčik, Jozef; Klejdus, Bořivoj; Štork, František; Hedbavny, Josef

2012-01-01

Highlights: ► Impact of foliar Cd, Ni and Cd + Ni application on Tillandsia albida was studied. ► Cd caused visible damage and enhanced stress parameters in combined treatment. ► Nitrogenous compounds were slightly affected but phenols were up- and down-regulated. ► Mineral nutrients (K, Ca, Na, Mg, Fe, and Zn) were not affected by any of treatments. ► Total Cd or Ni reached ca. 0.04% and Ni was more absorbed than Cd. - Abstract: The impact of 2-month foliar application of cadmium, nickel and their combination (10 μM) on Tillandsia albida was studied. Cadmium caused damage of tissue but assimilation pigments were depressed in Cd + Ni variant only. Stress-related parameters (ROS and peroxidase activities) were elevated by Cd and Cd + Ni while MDA content remained unaffected. Free amino acids accumulated the most in Ni alone but soluble proteins were not influenced. Among phenolic acids, mainly vanillin contributed to increase of their sum in all variants while soluble phenols even decreased in Cd + Ni and flavonols slightly increased in Cd variants. Phenolic enzymes showed negligible responses to almost all treatments. Mineral nutrients (K, Ca, Na, Mg, Fe, and Zn) were not affected by metal application but N content increased. Total Cd or Ni amounts reached over 400 μg g −1 DW and were not affected if metal alone and combined treatment is compared while absorbed content differed (ca. 50% of total Cd was absorbed while almost all Ni was absorbed). These data indicate tolerance of T. albida to foliar metal application and together with strong xerophytic morphology, use for environmental studies is recommended.

Influence of foliar fertilization on walnut foliar zinc levels and nut production in black walnut

Science.gov (United States)

William R. Reid; Andrew L. Thomas

2013-01-01

The impact of foliar zinc fertilizer application on nut-bearing black walnut (Juglans nigra L.) trees was studied. Foliar sprays were applied three times per season on two cultivars during four growing seasons by wetting the foliage of the entire crown using a tank mix containing 500 ppm zinc, starting at leaf burst and continuing at 2 week intervals...

Glyphosate resistance in Ambrosia trifida: Part 1. Novel rapid cell death response to glyphosate.

Science.gov (United States)

Van Horn, Christopher R; Moretti, Marcelo L; Robertson, Renae R; Segobye, Kabelo; Weller, Stephen C; Young, Bryan G; Johnson, William G; Schulz, Burkhard; Green, Amanda C; Jeffery, Taylor; Lespérance, Mackenzie A; Tardif, François J; Sikkema, Peter H; Hall, J Christopher; McLean, Michael D; Lawton, Mark B; Sammons, R Douglas; Wang, Dafu; Westra, Philip; Gaines, Todd A

2018-05-01

Glyphosate-resistant (GR) Ambrosia trifida is now present in the midwestern United States and in southwestern Ontario, Canada. Two distinct GR phenotypes are known, including a rapid response (GR RR) phenotype, which exhibits cell death within hours after treatment, and a non-rapid response (GR NRR) phenotype. The mechanisms of resistance in both GR RR and GR NRR remain unknown. Here, we present a description of the RR phenotype and an investigation of target-site mechanisms on multiple A. trifida accessions. Glyphosate resistance was confirmed in several accessions, and whole-plant levels of resistance ranged from 2.3- to 7.5-fold compared with glyphosate-susceptible (GS) accessions. The two GR phenotypes displayed similar levels of resistance, despite having dramatically different phenotypic responses to glyphosate. Glyphosate resistance was not associated with mutations in EPSPS sequence, increased EPSPS copy number, EPSPS quantity, or EPSPS activity. These encompassing results suggest that resistance to glyphosate in these GR RR A. trifida accessions is not conferred by a target-site resistance mechanism. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

influence of foliar applications of calcium chloride and borax on fruit

African Journals Online (AJOL)

Dr. A Rab

2011-12-16

Dec 16, 2011 ... The influence of foliar application of calcium chloride and borax calcium on fruit skin strength and cracking incidence in litchi (Litchi chinensis Sonn.) fruit was investigated at 25 days interval and also the evaluation of fruit skin calcium and boron contents, skin strength, ion leakage from skin discs and.

DIFFERENTIAL RESPONSE OF CLONES OF EUCALYPT TO GLYPHOSATE1

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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.

Avaliação do uso de glyphosate em soja geneticamente modificada e sua relação com o ácido chiquímico Evaluation of glyphosate application on transgenic soybean and its relationship with shikimic acid

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D.A.S. Franco

2012-09-01

plantas de soja transgênica no campo quando tratadas de forma isolada com glyphosate. Os resultados também mostraram exsudação radicular do glyphosate por soja transgênica, com posterior absorção por soja convencional. Foram detectados resíduos de glyphosate e ácido aminometilfosfônico na solução nutritiva.Glyphosate [N-(phosphonomethyl glycine]-resistant crops (GRC are the transgenic crops most extensively grown worldwide, with soybean being the major GRC. It is important to evaluate the impact of glyphosate on transgenic soybean and its relationship with shikimic acid. A field experiment was conducted at Engenheiro Coelho-SP, Brazil, during the agricultural year 2007/2008 to evaluate the effect of glyphosate on the growth, development, and seed quality of GRC soybean variety BRS Valiosa RR. A randomized block design was used with four replications. Glyphosate was applied at 720 and 960 g a.e. ha-1 (acid equivalent and in sequence at the doses 720/720, 960/720, and 960/720/720 g a.e. ha-1 (acid equivalent. To evaluate transfer from GRC soybean to non GRC soybean cultivated in nutrient solution, a pot experiment was conducted at Instituto Biológico, SP, Brazil. Glyphosate was applied on the GRC soybean (M8045RR at 2,400 g a.e. ha-1. Both GRC soybean and non GRC soybean were sown in the same box with nutrient solution. At 0, 1, 3, 7, and 10 days after application, shikimic acid was measured by HPLC and the glyphosate and aminomethylphosphonic acid (AMPA levels in nutrient solution were determined by GC-MS. The results showed that yield, plant height, seed oil, and protein contents were not affected by glyphosate application. GRC soybean accumulated shikimic acid in the field. Glyphosate and AMPA were released through the roots of GRC soybean, and subsequently taken up by non-GRC soybean, exerting inhibitory effects on their shikimic pathway.

Foliar application of calcium chloride and borax affects the fruit skin ...

African Journals Online (AJOL)

The influence of foliar application of calcium chloride and borax calcium on fruit skin strength and cracking incidence in litchi (Litchi chinensis Sonn.) fruit was investigated at 25 days interval and also the evaluation of fruit skin calcium and boron contents, skin strength, ion leakage from skin discs and fruit cracking in four ...

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

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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

Herbicide Glyphosate Impact to Earthworm (E. fetida

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Greta Dajoraitė

2016-10-01

Full Text Available Glyphosate is a broad spectrum weed resistant herbicide. Glyphosate may pose negative impact on land ecosystems because of wide broad usage and hydrofilic characteristic. The aim of this study was to investigate negative effects of glyphosate on soil invertebrate organisms (earthworm Eisenia fetida. The duration of experiment was 8 weeks. The range of the test concentrations of glyphosate were: 0,1, 1, 5, 10, 20 mg/kg. To investigate the glyphosate impact on earthworm Eisenia fetida the following endpoints were measured: survival, reproduction and weight. The exposure to 20 mg/kg glyphosate has led to the 100% mortality of earthworms. Glyphosate has led to decreased E. fetida reproduction, the cocoons were observed only in the lowest concentration (0,1 mg/kg. In general: long-term glyphosate toxicity to earthworms (E. fetida may be significant.

Manutenção da área foliar e produtividade de arroz irrigado com a aplicação de fertilizantes foliares no estádio de emborrachamento Foliar area maintenance and yield with application of foliar fertilizers on booting stage of irrigated rice

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Edinalvo Rabaioli Camargo

2008-08-01

Full Text Available A utilização de fertilizantes foliares, aplicados ao final do ciclo da cultura do arroz irrigado, pode proporcionar complementação nutricional para a planta e proteção contra patógenos com reflexos na produtividade. O objetivo do estudo foi avaliar a utilização de fertilizantes foliares, aplicados no estádio de emborrachamento, sobre a produtividade do arroz irrigado. O experimento foi conduzido no ano agrícola 2005/2006, em área experimental de várzea do Departamento de Fitotecnia da Universidade Federal de Santa Maria. O delineamento experimental utilizado foi o de blocos ao acaso com quatro repetições. Os tratamentos foram compostos por 10 fertilizantes foliares, dois produtos aplicados via sementes, um fungicida e a testemunha. Os fertilizantes não influenciaram qualquer parâmetro avaliado. As condições climáticas e o manejo da adubação anterior à aplicação dos tratamentos foliares propiciaram condições favoráveis para o arroz expressar o seu potencial produtivo, em torno de 10.000kg ha-1. Neste nível de produtividade, os produtos utilizados não aumentaram a produtividade do arroz irrigado.The use of foliar fertilizers applied to the reproductive phase of rice can improve the plant nutrition and protect the field against foliar diseases with gains in yield. The objective of this experiment was to evaluate the use of the foliar fertilizers applied to the booting stage in order to verify the irrigated rice yield. The experiment was carried out in 2005/06 in a lowland area in Santa Maria-RS, Brazil. The treatments, arranged in a randomized block design with four replications, were constituted by 10 foliar fertilizers available in the market, two products applied to seeds, a fungicide, and a check treatment. The treatments presented no effects on any of the variables studied. The suitable climatic conditions and the fertilizer management carried out before the application of the foliar treatments led to the

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

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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

Glyphosate efficacy on sourgrass biotypes with suspected resistance collected in GR-crop fields

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Hellen Martins da Silveira

2017-11-01

Full Text Available In Brazil, infestations of crop areas with glyphosate-resistant (GR sourgrass (Digitaria insularis (L. Fedde biotypes has risen significantly, increasing crop production costs. Glyphosate efficacy on three biotypes (GO, BA and MT of sourgrass with suspected resistance was evaluated. A susceptible biotype (MG was used as the control. The results confirmed that the MG and GO biotypes were susceptible to glyphosate (control > 90%. The MG biotype exhibited growth reduction and mortality by 50% (GR50 and LD50, respectively with mean glyphosate doses of 243.7 and 431.6 g ae ha-1. The resistance index of the biotypes with suspected resistance ranged from 2.8 to 6.1 in relation to GR50 and between 1.4 to 26.7 in relation to LD50. The glyphosate susceptibility ranking of the sourgrass biotypes was MG < GO < MT < BA. The MT and BA biotypes demonstrated high glyphosate resistance levels, and the GO biotype had a high potential to develop resistance. Farmers should avoid the application of glyphosate overdoses to minimize the selection pressure on weeds.

Simulating changes in cropping practises in conventional and glyphosate-tolerant maize. I. Effects on weeds.

Science.gov (United States)

Colbach, Nathalie; Fernier, Alice; Le Corre, Valérie; Messéan, Antoine; Darmency, Henri

2017-04-01

Herbicide-tolerant (HT) crops such as those tolerant to glyphosate simplify weed management and make it more efficient, at least at short-term. Overreliance on the same herbicide though leads to the spread of resistant weeds. Here, the objective was to evaluate, with simulations, the impact on the advent of glyphosate resistance in weeds of modifications in agricultural practises resulting from introducing HT maize into cropping systems. First, we included a single-gene herbicide resistance submodel in the existing multispecific FLORSYS model. Then, we (1) simulated current conventional and probable HT cropping systems in two European regions, Aquitaine and Catalonia, (2) compared these systems in terms of glyphosate resistance, (3) identified pertinent cultural practises influencing glyphosate resistance, and (4) investigated correlations between cultural practises and species traits, using RLQ analyses. The simulation study showed that, during the analysed 28 years, (1) glyphosate spraying only results in glyphosate resistance in weeds when combined with other cultural factors favouring weed infestation, particularly no till; (2) pre-sowing glyphosate applications select more for herbicide resistance than post-sowing applications on HT crops; and (3) glyphosate spraying selects more for species traits avoiding exposure to the herbicide (e.g. delayed early growth, small leaf area) or compensating for fitness costs (e.g. high harvest index) than for actual resistance to glyphosate, (4) actual resistance is most frequent in species that do not avoid glyphosate, either via plant size or timing, and/or in less competitive species, (5) in case of efficient weed control measures, actual resistance proliferates best in outcrossing species. An advice table was built, with the quantitative, synthetic ranking of the crop management effects in terms of glyphosate-resistance management, identifying the optimal choices for each management technique.

Physiological responses of Tillandsia albida (Bromeliaceae) to long-term foliar metal application

Energy Technology Data Exchange (ETDEWEB)

Kovacik, Jozef, E-mail: jozkovacik@yahoo.com [Institute of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, 613 00 Brno (Czech Republic); CEITEC - Central European Institute of Technology, Mendel University in Brno, Zemedelska 1, 613 00 Brno (Czech Republic); Klejdus, Borivoj [Institute of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, 613 00 Brno (Czech Republic); CEITEC - Central European Institute of Technology, Mendel University in Brno, Zemedelska 1, 613 00 Brno (Czech Republic); Stork, Frantisek [Department of Botany, Institute of Biology and Ecology, Faculty of Science, P. J. Safarik University, Manesova 23, 041 67 Kosice (Slovakia); Hedbavny, Josef [Institute of Chemistry and Biochemistry, Faculty of Agronomy, Mendel University in Brno, Zemedelska 1, 613 00 Brno (Czech Republic)

2012-11-15

Highlights: Black-Right-Pointing-Pointer Impact of foliar Cd, Ni and Cd + Ni application on Tillandsia albida was studied. Black-Right-Pointing-Pointer Cd caused visible damage and enhanced stress parameters in combined treatment. Black-Right-Pointing-Pointer Nitrogenous compounds were slightly affected but phenols were up- and down-regulated. Black-Right-Pointing-Pointer Mineral nutrients (K, Ca, Na, Mg, Fe, and Zn) were not affected by any of treatments. Black-Right-Pointing-Pointer Total Cd or Ni reached ca. 0.04% and Ni was more absorbed than Cd. - Abstract: The impact of 2-month foliar application of cadmium, nickel and their combination (10 {mu}M) on Tillandsia albida was studied. Cadmium caused damage of tissue but assimilation pigments were depressed in Cd + Ni variant only. Stress-related parameters (ROS and peroxidase activities) were elevated by Cd and Cd + Ni while MDA content remained unaffected. Free amino acids accumulated the most in Ni alone but soluble proteins were not influenced. Among phenolic acids, mainly vanillin contributed to increase of their sum in all variants while soluble phenols even decreased in Cd + Ni and flavonols slightly increased in Cd variants. Phenolic enzymes showed negligible responses to almost all treatments. Mineral nutrients (K, Ca, Na, Mg, Fe, and Zn) were not affected by metal application but N content increased. Total Cd or Ni amounts reached over 400 {mu}g g{sup -1} DW and were not affected if metal alone and combined treatment is compared while absorbed content differed (ca. 50% of total Cd was absorbed while almost all Ni was absorbed). These data indicate tolerance of T. albida to foliar metal application and together with strong xerophytic morphology, use for environmental studies is recommended.

Effect of polybag size and foliar application of urea on cocoa ...

African Journals Online (AJOL)

The effects of different polybag sizes and foliar application of urea on the growth of cocoa seedlings in the nursery were studied at the Cocoa Research Institute of Ghana substation at Afosu in the Eastern Region of Ghana between June 2004 and May 2005. Hybrid cocoa seeds were sown in polybags measuring 17.5 cm ...

Effect of Foliar Application of Chitosan on Growth and Biochemical Characteristics of Safflower (Carthamus tinctorius L. under Water Deficit Stress

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batool mahdavi

2014-09-01

Full Text Available In order to study the effects of water deficit stress and foliar application of chitosan in safflower (Carthamus tinctorius L., a pot experiment was conducted in 2009. Experimental design was a randomized complete block in factorial arrangement with three replications. Experimental factors were water deficit levels (unstressed (control and 70% available water depletion from soil (water deficit stress, chitosan concentrations (0, 0.05, 0.1%, all dissolved in 1% acetic acid along with an additional treatment of distilled water and foliar application times (before and during stem elongation. The results showed that water deficit stress reduced plant height, leaf area, shoot and root dry weight, root height and volume. Whereas, foliar application of chitosan increased mentioned traits. In addition, water deficit stress decreased chlorophyll fluorescence, chlorophyll concentration and relative water content. Carotenoid, proline and malondialdehyde (MDA content were increased in response to stress. Foliar application of chitosan increased chlorophyll fluorescence, relative water content (68.77% and chlorophyll b in the water deficit stressed plants, whereas decreased MDA content. The results of the present study indicate that application of chitosan can reduce the harmful effects of water deficit and improve plant growth.

Foliar additional nutrition in the fruit growing field

International Nuclear Information System (INIS)

Soare, M.; Borlan, Z.; Gavriluta, I.; Budoi, G.; Marinca, C.; Bandu, G.G.

1999-01-01

This paper presents data concerning the influence of foliar application of some types of complex foliar fertilizers under the conditions of SCPP Caransebes (Caras-Severin district). The composition of these nutrients fulfils the nutritional needs of the fruit growing species on the fruit yield obtained in orchards. The application of different types of foliar nutrients on plants teguments resulted in some significant yield increases for the two species that were studied: apple and plum tree. The novelty of this paper is represented by the apparent degrees of productive use in yields of the macro and micronutrients from foliar fertilizers, as well as the productive use degrees of nutrients present in soil and of the nutrients applied in soil (we took into account the mean values for the studied years). The apparent degrees of productive use (in yield increases) of the nutrients from complex foliar fertilizers applied on apple-trees and plum-trees generally exceed 100 %. They determine high levels of productive use of the nutrients from soil and foliar nutrients applied. The experimental data emphasize the ecological protection effect of the supplementary foliar fertilization for the yield stimulation especially on soils with light texture and sloping soils. Refs. 6 (author)

Overview of glyphosate-resistant weeds worldwide.

Science.gov (United States)

Heap, Ian; Duke, Stephen O

2018-05-01

Glyphosate is the most widely used and successful herbicide discovered to date, but its utility is now threatened by the occurrence of several glyphosate-resistant weed species. Glyphosate resistance first appeared in Lolium rigidum in an apple orchard in Australia in 1996, ironically the year that the first glyphosate-resistant crop (soybean) was introduced in the USA. Thirty-eight weed species have now evolved resistance to glyphosate, distributed across 37 countries and in 34 different crops and six non-crop situations. Although glyphosate-resistant weeds have been identified in orchards, vineyards, plantations, cereals, fallow and non-crop situations, it is the glyphosate-resistant weeds in glyphosate-resistant crop systems that dominate the area infested and growing economic impact. Glyphosate-resistant weeds present the greatest threat to sustained weed control in major agronomic crops because this herbicide is used to control weeds with resistance to herbicides with other sites of action, and no new herbicide sites of action have been introduced for over 30 years. Industry has responded by developing herbicide resistance traits in major crops that allow existing herbicides to be used in a new way. However, over reliance on these traits will result in multiple-resistance in weeds. Weed control in major crops is at a precarious point, where we must maintain the utility of the herbicides we have until we can transition to new weed management technologies. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

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

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 ...

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

content at the time of application and the level of the groundwater table relative to the drain depth was essential for whether solutes were detected in the drainage runoff. We present a leaching risk chart to illustrate the dependence of glyphosate, AMPA, and soil particle leaching based on precipitation......, 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...

Effect of Foliar Application of Iron, Zinc and Manganese on Quantitative and Qualitative Characteristics of Two Varieties of Grain Millet

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H. Javadi

2016-12-01

Full Text Available In order to study the effect of foliar application of Fe, Zn and Mn on yield, yield components and protein content of two varieties of grain millet an experiment was conducted as factorial based on randomized complete block design with three replications in research field of Birjand branch, Islamic Azad University at 2010.  In this study two millet varieties including Bastan (Setaria italica and Pishahang (Panicum miliaceum, and six levels of foliar micronutrient fertilizer including control, Fe, Zn, Mn, (Fe+Zn, (Fe+Zn+Mn were investigated. The results indicated that, panicle length, 1000 grain weight and panicle number per m2 were higher in Pishahang than Bastan, but grain yield, number of seeds per panicle, harvest index and protein yield were higher in Bastan. Characteristics such as panicle length, biological yield and harvest index and protein percentage were affected by foliar micronutrient fertilizer but grain yield remained unchanged. Foliar application with (Fe+Zn+Mn increased protein content compared to the control, but it did not affect protein yield. According to the results of this experiment, Bastan millet variety and foliar application of Zn is potent to produce the maximum grain yield, albeit it warrants further studies.

FOLIAR APPLICATION OF SILICON ON YIELD COMPONENTS OF WHEAT CROP

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THOMAS NEWTON MARTIN

2017-01-01

Full Text Available Wheat is a major winter crop in southern Brazil. To maximize its productivity, there should be no biotic or abiotic restrictions that can affect the yield components. Thus, the objective was to evaluate the changes caused in the wheat crop yield components by silicon foliar application. The experiment was conducted in two growing seasons. In the first year, five wheat cultivars (Quartzo, Campo Real, Onix and Fundacep Lineage were assessed and in the second year four were assessed (Mirante, Campo Real, Horizonte and Quartzo. In both years the crops were subjected to three doses of silicon (0, 3 and 6 L of silicon ha -1. The silicon was applied during the tillering, booting and anthesis stages. The yield components assessed were the number of plants, number of ears, number of fertile tillers, dry matter per plant, hectoliter weight, number of spikelets, number of grains per spike, weight of hundred grains, grain yield and harvest index. Most yield components did not respond to the silicon foliar application. The harvest index (first year and the number of tillers (second year however presented a quadratic relationship with the supply of silicon. The remaining differences were attributed to variations among the wheat cultivars.

Foliar application effects of beet vinasse on rice yield and chemical composition

International Nuclear Information System (INIS)

Tejada, M.; Garcia-Martinez, A. M.; Benitez, C.; Gonzalez, J. L.; Bautista, J.; Parrado, J.

2009-01-01

This study presents an account of rice (oriza sativa cv. Puntal) yield quality parameters as influenced by the foliar application of an industrial byproduct (beet vinasse). Beet (Beta vulgaris L. Subsp.vurgaris) vinasse is a product of great agricultural interest, because of its organic matter content, N and K concentrations. (Author)

Studies on transfer, bioaccumulation and disappearance of glyphosate in the aquatic ecosystem by utilizing 14C tracer technique

International Nuclear Information System (INIS)

Zhu Guonian; Guo Jiangfeng; Sun Jinhe

2002-01-01

Studies on transfer, bioaccumulation and disappearance of glyphosate in the aquatic environment were conducted with methods of model tests and outdoor trials in the aquatic ecosystem. The result showed that glyphosate transferred rapidly into sediment and hormwort (Ceratopyllum demersum L.) after applied; and then, it was taken up faster and accumulated more by topmouth gudgeon (Psudorasobora parva) 5-10 days after application. The partitioning coefficient (sediment-water) and bioconcentration factors of glyphosate were 8.59, 27.96 and 45.79, respectively, in day 20. The concentration of glyphosate residue in the aquatic ecosystem followed the order of topmouth gudgeon > hormwort > sediment > water. And it was also indicated that glyphosate transferred and disappeared extremely fast in both pond and river after application

Effect of foliar application of chitosan and salicylic acid on the growth of soybean (Glycine max (L.) Merr.) varieties

Science.gov (United States)

Hasanah, Y.; Sembiring, M.

2018-02-01

Elicitors such as chitosan and salicylic acid could be used not only to increase isoflavone concentration of soybean seeds, but also to increase the growth and seed yield. The objective of the present study was to determine the effects of foliar application of elicitor compounds (i.e. chitosan, and salicylic acid)on the growth of two soybean varieties under dry land conditions. Experimental design was a randomized block design with 2 factors and 3 replications. The first factor was soybean varieties (Wilis and Devon). The second factor was foliar application of elicitors consisted of without elicitor; chitosan at V4 (four trifoliate leaves are fully developed); chitosan at R3 (early podding); chitosan at V4 and R3; salicylic acid at V4; salicylic acid at R3 and salicylic acid at V4 and R3. Parameters observed was plant height at 2-7 week after planting (WAP), shoot dry weight and root dry weight. The results suggest that the Wilis variety had higher plant height 7 WAP than Devon. The foliar application of chitosan increased the plant height at 7 WAP, shoot dry weight and root dry weight. The foliar application of chitosan at V4 and R3 on Devon variety increased shoot dry weight.

Does nitrogen fertilization history affects short-term microbial responses and chemical properties of soils submitted to different glyphosate concentrations?

Directory of Open Access Journals (Sweden)

Elodie Nivelle

Full Text Available The use of nitrogen (N fertilizer and glyphosate-based herbicides is increasing worldwide, with agriculture holding the largest market share. The agronomic and socioeconomic utilities of glyphosate are well established; however, our knowledge of the potential effects of glyphosate applied in the presence or absence of long-term N fertilization on microbial functional activities and the availability of soil nutrients remains limited. Using an ex situ approach with soils that did (N+ or did not (N0 receive synthetic N fertilization for 6 years, we assessed the impact of different rates (no glyphosate, CK; field rate, FR; 100 × field rate, 100FR of glyphosate application on biological and chemical parameters. We observed that, after immediate application (1 day, the highest dose of glyphosate (100FR negatively affected the alkaline phosphatase (AlP activity in soils without N fertilization history and decreased the cation exchange capacity (CEC in N0 compared to CK and FR treatments with N+. Conversely, the 100FR application increased nitrate (NO3- and available phosphorus (PO43- regardless of N fertilization history. Then, after 8 and 15 days, the N+\\100FR and N+\\FR treatments exhibited the lowest values for dehydrogenase (DH and AlP activities, respectively, while urease (URE activity was mainly affected by N fertilization. After 15 days and irrespective of N fertilization history, the FR glyphosate application negatively affected the degradation of carbon substrates by microbial communities (expressed as the average well color development, AWCD. By contrast, the 100FR treatment positively affected AWCD, increasing PO43- by 5 and 16% and NO3- by 126 and 119% in the N+ and N0 treatments, respectively. In addition, the 100FR treatment resulted in an increase in the average net nitrification rate. Principal component analysis revealed that the 100FR glyphosate treatment selected microbial communities that were able to metabolize amine substrates

Induction of drought tolerance in zea mays l. by foliar application of triacontanol

International Nuclear Information System (INIS)

Perveen, S.; Iqbal, M.; Nawaz, A.

2016-01-01

In the present study, we assessed the effect of foliar application of triacontanol (TRIA) on various growth and physiochemical parameters of two maize (Zea mays L.) cultivars (cv. MMRI-Yellow and cv. Hybrid S-515) under different irrigation levels i.e., normal watering (control) and watering at 60% of the field capacity (drought). Seeds of the two maize cultivars were sown in plastic pots filled with sandy loam soil (2 kg in each). Foliar application of TRIA (0, 2 and 5 micro M) was performed after two weeks of drought stress to 28-day-old plants. Data of 58-day-old maize plants was collected for analysis of various growth and physiochemical attributes. Drought stress significantly decreased growth and superoxide dismutase (SOD) activity while increased the activities of catalase (CAT) and peroxidase (POD) and the contents of total phenolics, total soluble proteins, glycinebetaine (GB) and free proline. Foliar treatment with TRIA further increased CAT and POD activities whereas decreased the contents of hydrogen peroxide (H/sub 2/O/sub 2/), malondialdehyde (MDA), total phenolics and GB in the maize plants when under drought stress. Of the two maize cultivars, cv. MMRI-Yellow excelled the growth under both normal and drought stress (60% of the field capacity). Overall, TRIA (5 micro M) was much more effective in modulating various growth and physiochemical attributes, and thus improving drought tolerance in maize plants. (author)

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.

76 FR 27268 - Glyphosate; Pesticide Tolerance

Science.gov (United States)

2011-05-11

... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 180 [EPA-HQ-OPP-2010-0938; FRL-8872-6] Glyphosate... regulation increases the established tolerance for residues of glyphosate in or on corn, field, forage... tolerance for residues of the herbicide glyphosate, N-(phosphonomethyl) glycine, in or on corn, field...

Zinc complexed chitosan/TPP nanoparticles: A promising micronutrient nanocarrier suited for foliar application.

Science.gov (United States)

Deshpande, Paresh; Dapkekar, Ashwin; Oak, Manoj D; Paknikar, Kishore M; Rajwade, Jyutika M

2017-06-01

Cultivation of cereals in zinc deficient soils leads to declined nutritional quality of grain. Zinc deficiency in humans is a consequence of consumption of micronutrient deficient cereals as staple food. To achieve an increase in zinc density in grain, we evaluated zinc complexed chitosan nanoparticles (Zn-CNP) as a potential 'nanocarrier' suited for foliar fertilization. Zn-CNP were synthesized using tri-polyphosphate as a cross-linker. Spherical Zn-CNP (diameter 250-300nm) were positively charged (zeta potential, +42.34mV) and contained ∼20mg Zn/g (w/w). Plant growth in zinc deficient sand media, followed by foliar application of Zn-CNP (twice-a-week, for 5 weeks) after anthesis resulted in 27 and 42% increase in grain zinc content of MACS 3125 and UC1114 (durum wheat cultivars) respectively. Translocation of zinc ions from foliar applied Zn-CNP into the leaf and seed tissue was demonstrated using zinquin and dithizone stains, respectively. The study indicates the suitability of chitosan-based nanocarriers in agronomic biofortification. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of glyphosate on the microbial activity of two Romanian soils.

Science.gov (United States)

Sumalan, R M; Alexa, E; Negrea, M; Sumalan, R L; Doncean, A; Pop, G

2010-01-01

Glyphosate applied to soils potentially affect microbial activity. A series of field and laboratory experiments assessed the effect of this herbicide on soil microorganisms. The aim of experiments was to evaluate the effect of glyphosate application on the soil microbial community structure, function and their activity. We studied "in vitro", changes in the microbial activity of typical Chernozem and Gleysol soils, with and without applied glyphosate. The herbicide was applied at a rate of 2, respectively 4 mg kg(-1) of soil and microbial activity were measured by fluorescein diacetate (FDA) hydrolysis. We found an increase of 9 to 13% in FDA hydrolyses in the presence of glyphosate in rate of 2 mg kg (-1) compared with the same type of soil which had never received herbicide. The double quantity of glyphosate decrease soil microbial activity; the amount of hydrolyzed fluorescein is lower than the addition of 2 ppm. The greater decrease was observed in the Gleysol type where the fluorescein hydrolyzed is with 4, 85% lower than version control without glyphosate. Chemical characters of soil, influence soil biological activity when herbicide is added. In Chemozem case, rich in humus, whose predominant micro flora is represented by actinomycetes through glyphosate treatment these organisms growths of as major producers of antibiotics actinomycetes determine an inhibitory effect on eubacteria and micromycetes growth, which is highlighted by estimating a relatively small number of them. After 10 days, once with decreasing of glyphosate content in soil, decreases the number of active actinomycetes, therefore we are witnessing to a numerical growth of bacterial population. In Gleysol type the indigenous micro flora is represented by eubacteria, so when the glyphosate is added it was registered a high growth of these organisms fraction.

Effect of two doses of urea foliar application on leaves and grape nitrogen composition during two vintages.

Science.gov (United States)

Pérez-Álvarez, Eva P; Garde-Cerdán, Teresa; García-Escudero, Enrique; Martínez-Vidaurre, José María

2017-06-01

Nitrogen affects grapevine growth and also yeast metabolism, which have a direct influence on fermentation kinetics and the formation of different volatile compounds. Throughout the grapevine cycle, soil nitrogen availability and grape nitrogen composition can vary because of different factors. Nitrogen foliar applications can contribute toward enhancing grapevine nitrogen status and minimize the problem of leaching that traditional nitrogen-soil applications can provoke. The present study aimed to evaluate the influence of urea foliar applications on grapevine nitrogen status and grape amino acid content. Accordingly, two different doses of urea were applied over the leaves of a 'Tempranillo' vineyard. The highest urea doses affected nitrogen content on blade leaf tissues after veraison. Must amino acid profiles were modified by urea application and some of the compounds increased their concentrations. The effect of year on the increase of must total amino acid concentrations was more important than the effect of the doses applied. Urea foliar applications can be an interesting tool for decreasing grapevine nitrogen deficiencies. This method of nitrogen implementation in the vineyard could avoid sluggish fermentation problems during winemaking, enhance must nitrogen composition, and contribute to improving wine quality. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Costs and benefits of insecticide and foliar nutrient applications to huanglongbing-infected citrus trees.

Science.gov (United States)

Tansey, James A; Vanaclocha, Pilar; Monzo, Cesar; Jones, Moneen; Stansly, Philip A

2017-05-01

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Psyllidae), vectors Candidatus Liberibacter asiaticus, which causes huanglongbing (HLB). In Florida, HLB incidence is approaching 100% statewide. Yields have decreased and production costs have increased since 2005. Despite this, some growers are maintaining a level of production and attribute this in part to aggressive psyllid control and foliar nutrition sprays. However, the value of these practices is debated. A replicated field study was initiated in 2008 in a commercial block of 'Valencia' sweet orange trees to evaluate individual and combined effects of foliar nutrition and ACP control. Results from 2012-2016 are presented. Insecticides consistently reduced ACP populations. However, neither insecticide nor nutrition applications significantly influenced HLB incidence or PCR copy number in mature trees. In reset trees, infection continued to build and reached 100% in all treatments. Greatest yields (kg fruit ha -1 ) and production (kg solids ha -1 ) were obtained from trees receiving both insecticides and foliar nutrition. All treatments resulted in production and financial gains relative to controls. However, material and application costs associated with the nutrition component offset these gains, resulting in lesser benefits than insecticides applied alone. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

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

Is it time to reassess current safety standards for glyphosate-based herbicides?

Science.gov (United States)

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

2017-06-01

Use of glyphosate-based herbicides (GBHs) increased ∼100-fold from 1974 to 2014. Additional increases are expected due to widespread emergence of glyphosate-resistant weeds, increased application of GBHs, and preharvest uses of GBHs as desiccants. Current safety assessments rely heavily on studies conducted over 30 years ago. We have considered information on GBH use, exposures, mechanisms of action, toxicity and epidemiology. Human exposures to glyphosate are rising, and a number of in vitro and in vivo studies challenge the basis for the current safety assessment of glyphosate and GBHs. We conclude that current safety standards for GBHs are outdated and may fail to protect public health or the environment. To improve safety standards, the following are urgently needed: (1) human biomonitoring for glyphosate and its metabolites; (2) prioritisation of glyphosate and GBHs for hazard assessments, including toxicological studies that use state-of-the-art approaches; (3) epidemiological studies, especially of occupationally exposed agricultural workers, pregnant women and their children and (4) evaluations of GBHs in commercially used formulations, recognising that herbicide mixtures likely have effects that are not predicted by studying glyphosate alone. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Sources of aminomethylphosphonic acid (AMPA) in urban and rural catchments in Ontario, Canada: Glyphosate or phosphonates in wastewater?

International Nuclear Information System (INIS)

Struger, J.; Van Stempvoort, D.R.; Brown, S.J.

2015-01-01

Correlation analysis suggests that occurrences of AMPA in streams of southern Ontario are linked mainly to glyphosate in both urban and rural settings, rather than to wastewater sources, as some previous studies have suggested. For this analysis the artificial sweetener acesulfame was analyzed as a wastewater indicator in surface water samples collected from urban and rural settings in southern Ontario, Canada. This interpretation is supported by the concurrence of seasonal fluctuations of glyphosate and AMPA concentrations. Herbicide applications in larger urban centres and along major transportation corridors appear to be important sources of glyphosate and AMPA in surface water, in addition to uses of this herbicide in rural and mixed use areas. Fluctuations in concentrations of acesulfame and glyphosate residues were found to be related to hydrologic events. - Highlights: • Widespread occurrence of glyphosate and AMPA in surface waters of southern Ontario. • Linked to applications of glyphosate in urban and rural settings. • Supported by lack of correlation between AMPA and the wastewater tracer acesulfame. • Contrasts with view that AMPA found in the environment is derived from wastewater. • AMPA more persistent than glyphosate and both fluctuated with hydrological cycles. - The occurrence of AMPA in streams in southern Ontario is linked mainly to glyphosate rather than wastewater sources

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

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

Fate of glyphosate and degradates in cover crop residues and underlying soil: A laboratory study

Energy Technology Data Exchange (ETDEWEB)

Cassigneul, A. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France); INRA, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Benoit, P.; Bergheaud, V.; Dumeny, V.; Etiévant, V. [INRA, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Goubard, Y. [AgroParisTech, UMR 1402 ECOSYS, 78850 Thiverval-Grignon (France); Maylin, A. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France); Justes, E. [INRA, UMR 1248 AGIR Auzeville — BP 52 627, 31 326, Castanet-Tolosan cedex (France); Alletto, L. [Université de Toulouse — École d' ingénieurs de Purpan, UMR 1248 AGIR — 75, Voie du TOEC BP 57 611, 31 076, Toulouse cedex 3 (France)

2016-03-01

The increasing use of cover crops (CC) may lead to an increase in glyphosate application for their destruction. Sorption and degradation of {sup 14}C-glyphosate on and within 4 decaying CC-amended soils were compared to its fate in a bare soil. {sup 14}C-Glyphosate and its metabolites distribution between mineralized, water-soluble, NH{sub 4}OH-soluble and non-extractable fractions was determined at 5 dates during a 20 °C/84-d period. The presence of CC extends {sup 14}C-glyphosate degradation half-life from 7 to 28 days depending on the CC. {sup 14}C-Glyphosate dissipation occurred mainly through mineralization in soils and through mineralization and bound residue formation in decaying CC. Differences in sorption and degradation levels were attributed to differences in composition and availability to microorganisms. CC- and soil-specific dissipation patterns were established with the help of explicit relationships between extractability and microbial activity. - Highlights: • Glyphosate sorption on cover crop residues increases with their decomposition degree. • Glyphosate degradation and mineralization are lower in mulch than in soil. • Nonextractable residue formation is one of the main dissipation pathways of glyphosate in cover crop mulch.

Fate of glyphosate and degradates in cover crop residues and underlying soil: A laboratory study

International Nuclear Information System (INIS)

Cassigneul, A.; Benoit, P.; Bergheaud, V.; Dumeny, V.; Etiévant, V.; Goubard, Y.; Maylin, A.; Justes, E.; Alletto, L.

2016-01-01

The increasing use of cover crops (CC) may lead to an increase in glyphosate application for their destruction. Sorption and degradation of "1"4C-glyphosate on and within 4 decaying CC-amended soils were compared to its fate in a bare soil. "1"4C-Glyphosate and its metabolites distribution between mineralized, water-soluble, NH_4OH-soluble and non-extractable fractions was determined at 5 dates during a 20 °C/84-d period. The presence of CC extends "1"4C-glyphosate degradation half-life from 7 to 28 days depending on the CC. "1"4C-Glyphosate dissipation occurred mainly through mineralization in soils and through mineralization and bound residue formation in decaying CC. Differences in sorption and degradation levels were attributed to differences in composition and availability to microorganisms. CC- and soil-specific dissipation patterns were established with the help of explicit relationships between extractability and microbial activity. - Highlights: • Glyphosate sorption on cover crop residues increases with their decomposition degree. • Glyphosate degradation and mineralization are lower in mulch than in soil. • Nonextractable residue formation is one of the main dissipation pathways of glyphosate in cover crop mulch.

Glyphosate: too much of a good thing?

Directory of Open Access Journals (Sweden)

Marek eCuhra

2016-04-01

Full Text Available Although previously accepted as the less toxic alternative, with low impact on animals, farmers as well as consumers who are exposed to residues in food, glyphosate chemicals are now increasingly controversial as new evidence from research is emerging. We argue that specific aspects of the history, chemistry and safety of glyphosate and glyphosate-based herbicides should be thoroughly considered in present and future re-evaluations of these dominant agrochemicals:· Glyphosate is not a single chemical, it is a family of compounds with different chemical, physical and toxicological properties.· Glyphosate is increasingly recognized as having more profound toxicological effects than assumed from previous assessments.· Global use of glyphosate is continuously increasing and residues are detected in food, feed and drinking water. Thus, consumers are increasingly exposed to higher levels of glyphosate residues, and from an increasing number of sources.· Glyphosate regulation is predominantly still based on primary safety-assessment testing in various indicator organisms. However, archive studies indicate fraud and misbehavior committed by the commercial laboratories providing such research.We see emerging evidences from studies in test-animals, ecosystems indicators and studies in human health, which justify stricter regulatory measures. This implies revising glyphosate residue definitions and lowering Maximum Residue Limits (MRLs permissible in biological material intended for food and feed, as well as strengthening environmental criteria such as accepted residue concentrations in surface waters.It seems that although recent research indicates that glyphosates are less harmless than previously assumed and have complex toxicological potential, still regulatory authorities accept industry demands for approving higher levels of these residues in food and feed.

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 (pretention capacity in soils. Copyright © 2015. Published by Elsevier B.V.

Indirect glyphosate detection based on ninhydrin reaction and surface-enhanced Raman scattering spectroscopy

Science.gov (United States)

Xu, Meng-Lei; Gao, Yu; Li, Yali; Li, Xueliang; Zhang, Huanjie; Han, Xiao Xia; Zhao, Bing; Su, Liang

2018-05-01

Glyphosate is one of the most commonly-used and non-selective herbicides in agriculture, which may directly pollute the environment and threaten human health. A simple and effective approach to assessment of its damage to the natural environment is thus quite necessary. However, traditional chromatography-based detection methods usually suffer from complex pretreatment procedures. Herein, we propose a simple and sensitive method for the determination of glyphosate by combining ninhydrin reaction and surface-enhanced Raman scattering (SERS) spectroscopy. The product (purple color dye, PD) of the ninhydrin reaction is found to SERS-active and directly correlate with the glyphosate concentration. The limit of detection of the proposed method for glyphosate is as low as 1.43 × 10- 8 mol·L- 1 with a relatively wider linear concentration range (1.0 × 10- 7-1.0 × 10- 4 mol·L- 1), which demonstrates its great potential in rapid, highly sensitive concentration determination of glyphosate in practical applications for safety assessment of food and environment.

Physiological responses of Tillandsia albida (Bromeliaceae) to long-term foliar metal application.

Science.gov (United States)

Kováčik, Jozef; Klejdus, Bořivoj; Stork, František; Hedbavny, Josef

2012-11-15

The impact of 2-month foliar application of cadmium, nickel and their combination (10 μM) on Tillandsia albida was studied. Cadmium caused damage of tissue but assimilation pigments were depressed in Cd+Ni variant only. Stress-related parameters (ROS and peroxidase activities) were elevated by Cd and Cd+Ni while MDA content remained unaffected. Free amino acids accumulated the most in Ni alone but soluble proteins were not influenced. Among phenolic acids, mainly vanillin contributed to increase of their sum in all variants while soluble phenols even decreased in Cd+Ni and flavonols slightly increased in Cd variants. Phenolic enzymes showed negligible responses to almost all treatments. Mineral nutrients (K, Ca, Na, Mg, Fe, and Zn) were not affected by metal application but N content increased. Total Cd or Ni amounts reached over 400 μg g(-1) DW and were not affected if metal alone and combined treatment is compared while absorbed content differed (ca. 50% of total Cd was absorbed while almost all Ni was absorbed). These data indicate tolerance of T. albida to foliar metal application and together with strong xerophytic morphology, use for environmental studies is recommended. Copyright © 2012 Elsevier B.V. All rights reserved.

Crescimento diferencial de biótipos de Conyza SPP. resistente e suscetível ao herbicida glifosato Differential growth of glyphosate-resistant and susceptible biotypes of Conyza SPP

Directory of Open Access Journals (Sweden)

Murilo Sala Moreira

2010-01-01

Full Text Available Este trabalho foi realizado com o objetivo de comparar, em condição controlada e não-competitiva, o crescimento de biótipos de Conyza canadensis e C. bonariensis resistente e suscetível ao herbicida glifosato, a fim de quantificar os efeitos da pressão de seleção para resistência nos biótipos. Dois experimentos foram desenvolvidos com tratamentos organizados em esquema fatorial 9 x 2, com nove avaliações periódicas de crescimento e dois biótipos de cada espécie. As variáveis avaliadas por planta foram: área foliar; massa seca da parte aérea, das raízes e total, obtendo-se, a partir desta última, a taxa de crescimento absoluto. O biótipo de C. canadensis resistente ao glifosato possui crescimento mais lento, menor acúmulo de área foliar e de massa seca que o biótipo suscetível. Menores áreas foliar e massa seca também foram registradas para o biótipo de C. bonariensis resistente ao glifosato quando comparado ao suscetível, porém com diferenças mais sutis que aquelas constatadas para C. canadensis. O crescimento absoluto do biótipo suscetível foi superior ao do resistente em ambas as espécies. A pressão de seleção para resistência ao glifosato teve impactos negativos na habilidade de crescimento dos biótipos.This work was carried out with the objective of comparing, under controlled and non-competitive condition, the growth of glyphosate-resistant and susceptible biotypes of Conyza canadensis and C. bonariensis; to quantify the effects of resistance selection pressure on the biotypes. Two trials were developed with treatments organized according to a factorial scheme 9 x 2, where nine were periodical growth evaluations and two were biotypes of each species. The variables evaluated per plant were: leaf area and dry mass (shoot, root and total; to determine absolute growth rate from the total dry mass. The glyphosate-resistant biotype of C. canadensis exhibits slower growth and smaller accumulation of leaf area

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.

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

2014-01-01

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. PMID:25005713

Environmental and health effects of the herbicide glyphosate.

Science.gov (United States)

Van Bruggen, A H C; He, M M; Shin, K; Mai, V; Jeong, K C; Finckh, M R; Morris, J G

2018-03-01

The herbicide glyphosate, N-(phosphonomethyl) glycine, has been used extensively in the past 40years, under the assumption that side effects were minimal. However, in recent years, concerns have increased worldwide about the potential wide ranging direct and indirect health effects of the large scale use of glyphosate. In 2015, the World Health Organization reclassified glyphosate as probably carcinogenic to humans. A detailed overview is given of the scientific literature on the movement and residues of glyphosate and its breakdown product aminomethyl phosphonic acid (AMPA) in soil and water, their toxicity to macro- and microorganisms, their effects on microbial compositions and potential indirect effects on plant, animal and human health. Although the acute toxic effects of glyphosate and AMPA on mammals are low, there are animal data raising the possibility of health effects associated with chronic, ultra-low doses related to accumulation of these compounds in the environment. Intensive glyphosate use has led to the selection of glyphosate-resistant weeds and microorganisms. Shifts in microbial compositions due to selective pressure by glyphosate may have contributed to the proliferation of plant and animal pathogens. Research on a link between glyphosate and antibiotic resistance is still scarce but we hypothesize that the selection pressure for glyphosate-resistance in bacteria could lead to shifts in microbiome composition and increases in antibiotic resistance to clinically important antimicrobial agents. We recommend interdisciplinary research on the associations between low level chronic glyphosate exposure, distortions in microbial communities, expansion of antibiotic resistance and the emergence of animal, human and plant diseases. Independent research is needed to revisit the tolerance thresholds for glyphosate residues in water, food and animal feed taking all possible health risks into account. Copyright © 2017 Elsevier B.V. All rights reserved.

Lack of transgene and glyphosate effects on yield, and mineral and amino acid content of glyphosate-resistant soybean.

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Duke, Stephen O; Rimando, Agnes M; Reddy, Krishna N; Cizdziel, James V; Bellaloui, Nacer; Shaw, David R; Williams, Martin M; Maul, Jude E

2018-05-01

There has been controversy as to whether the glyphosate resistance gene and/or glyphosate applied to glyphosate-resistant (GR) soybean affect the content of cationic minerals (especially Mg, Mn and Fe), yield and amino acid content of GR soybean. A two-year field study (2013 and 2014) examined these questions at sites in Mississippi, USA. There were no effects of glyphosate, the GR transgene or field crop history (for a field with both no history of glyphosate use versus one with a long history of glyphosate use) on grain yield. Furthermore, these factors had no consistent effects on measured mineral (Al, As, Ba, Cd, Ca, Co, Cr, Cs, Cu, Fe, Ga, K, Li, Mg, Mn, Ni, Pb, Rb, Se, Sr, Tl, U, V, Zn) content of leaves or harvested seed. Effects on minerals were small and inconsistent between years, treatments and mineral, and appeared to be random false positives. No notable effects on free or protein amino acids of the seed were measured, although glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), were found in the seed in concentrations consistent with previous studies. Neither glyphosate nor the GR transgene affect the content of the minerals measured in leaves and seed, harvested seed amino acid composition, or yield of GR soybean. Furthermore, soils with a legacy of GR crops have no effects on these parameters in soybean. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

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

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S.J.P. Carvalho

2010-01-01

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

Circadian response of annual weeds to glyphosate and glufosinate.

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Martinson, Krishona B; Sothern, Robert B; Koukkari, Willard L; Durgan, Beverly R; Gunsolus, Jeffrey L

2002-03-01

Five field experiments were conducted in 1998 and 1999 in Minnesota to examine the influence of time of day efficacy of glyphosate [N-(phosphonomethyl)glycine] and glufosinate [2-amino-4-(hydroxymethyl-phosphinyl)butanoic acid] applications on the control of annual weeds. Each experiment was designed to be a randomized complete block with four replications using plot sizes of 3 x 9 m. Glyphosate and glufosinate were applied at rates of 0.421 kg ae/ha and 0.292 kg ai/ha, respectively, with and without an additional adjuvant that consisted of 20% nonionic surfactant and 80% ammonium sulfate. All treatments were applied with water at 94 L/ha. Times of day for the application of herbicide were 06:00h, 09:00h, 12:00h, 15:00h, 18:00h, 21:00h, and 24:00h. Efficacy was evaluated 14 d after application by visual ratings. At 14 d, a circadian response to each herbicide was found, with greatest annual weed control observed with an application occurring between 09:00h and 18:00h and significantly less weed control observed with an application at 06:00h, 21:00h, or 24:00h. The addition of an adjuvant to both herbicides increased overall efficacy, but did not overcome the rhythmic time of day effect. Results of the multiple regression analysis showed that after environmental temperature, time of day was the second most important predictor of percent weed kill. Thus, circadian timing of herbicide application significantly influenced weed control with both glyphosate and glufosinate.

Glyphosate toxicity and the effects of long-term vegetation control on soil microbial communities

Science.gov (United States)

Matt D. Busse; Alice W. Ratcliff; Carol J. Stestak; Robert F. Powers

2001-01-01

We assessed the direct and indirect effect of the herbicide glyphosate on soil microbial communities from soil bioassays at glyphosate concentrations up to 100-fold greater than expected following a single field application. Indirect effects on microbial biomass, respiration, and metabolic diversity (Biolog and catabolic response profile) were compared seasonally after...

The effect of glyphosate application on soil microbial activities in ...

African Journals Online (AJOL)

Yomi

2011-12-21

Dec 21, 2011 ... bacterial populations in the presence of glyphosate as P source was significantly (p<0.01) higher than N ... bes by transferring hydrogen or electrons from substrates .... of utilizing GP as carbon or other nutrient sources.

Effects of Vermi-compost Fertilizer Application and Foliar Spraying on Yield and Yield Component of Isabgol (Plantago ovate L. Medicinal Plant

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Asghar Rahimi

2017-12-01

Full Text Available Introduction Vermi-compost is the ability of some species of earthworms to consume and break down a wide range of organic residues such as sewage sludge, animal wastes, crop residues and industrial refuse. Vermi-composts are usually more stable than their parent materials with increased availability of nutrients and improved physicochemical and microbiological properties. Aerial compost tea contains high populations of live microorganism consisting of rhizobactria, trichoderma and pseudomonas species which increase the growth and yield of the plant. Acid humic is the main humic substance and the important ingredient of soil organic matter (humus which causes increase of yield and quality of crop. The aim of this research is evaluating the effect of vermi-compost and foliar application of compost tea and acid humic on yield, yield component and mucilage content of isabgol. Vermiwash as the extract of vermi-compost is liquid organic fertilizer obtained from unit of vermiculture and vermi-compost as drainage. It is used as a foliar spraying on the leaf. Vermiwash stimulate and increase the yield of crop products and foliar application of vermiwash can be caused of plant resistance to different factors and can prevent leaf necrosis. Material and Methods In order to study the effect of vermi-compost and foliar application of tea compost and acid humic on growth indices of isabgol (Plantago ovata, an experiment was conducted as a factorial based on complete randomized design with three replications in agricultural research farm at Vali-e-Asr University of Rafsanjan. Treatments were included application of vermi-compost (0 (control, 4, 8, 12 and 16 t.ha-1 and 3 levels of foliar application (distilled water as control, acid humic and compost tea. Samples for evaluating of yield, yield components and mucilage content were taken from 1 m2 area of each treatment. Tea compost solution prepared using mix of vermi-compost, acid humic, yeast and alga extract

Foliar application with nano-silicon alleviates Cd toxicity in rice seedlings.

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Wang, Shihua; Wang, Fayuan; Gao, Shuangcheng

2015-02-01

Nanofertilizers may be more effective than regular fertilizers in improving plant nutrition, enhancing nutrition use efficiency, and protecting plants from environmental stress. A hydroponic pot experiment was conducted to study the role of foliar application with 2.5 mM nano-silicon in alleviating Cd stress in rice seedlings (Oryza sativa L. cv Youyou 128) grown in solution added with or without 20 μM CdCl2. The results showed that Cd treatment decreased the growth and the contents of Mg, Fe, Zn, chlorophyll a, and glutathione (GSH), accompanied by a significant increase in Cd accumulation. However, foliar application with nano-Si improved the growth, Mg, Fe, and Zn nutrition, and the contents of chlorophyll a of the rice seedlings under Cd stress and decreased Cd accumulation and translocation of Cd from root to shoot. Cd treatment produced oxidative stress to rice seedlings indicated by a higher lipid peroxidation level (as malondialdehyde (MDA)) and higher activities of antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and a lower GSH content. However, those nano-Si-treated plants had lower MDA but higher GSH content and different antioxidant enzyme activities, indicating a higher Cd tolerance in them. The results suggested that nano-Si application alleviated Cd toxicity in rice by decreasing Cd accumulation, Cd partitioning in shoot and MDA level and by increasing content of some mineral elements (Mg, Fe, and Zn) and antioxidant capacity.

Absorção e redistribuição do nitrogênio aplicado via foliar em videiras jovens Uptake and redistribution of nitrogen in foliar application in young grapevines

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Gustavo Brunetto

2005-04-01

Full Text Available A aplicação de nitrogênio via foliar antes da senescência das folhas da videira pode ser uma estratégia para aumentar as reservas deste nutriente nas partes perenes, uma vez que as mesmas são disponibilizadas no início do crescimento vegetativo dos órgãos anuais. O objetivo deste trabalho foi de estimar a absorção e a redistribuição do N adicionado via foliar em videiras jovens. O experimento foi instalado em casa de vegetação na EMBRAPA-Uva e Vinho, no município de Bento Gonçalves (RS. Foram utilizadas as variedades Chardonnay e Riesling Itálico com porta-enxerto 101-14 Mgt. Foi cultivada uma planta por vaso contendo 10kg de solo Neossolo Litólico. A aplicação do N via foliar foi parcelada em três vezes, durante três dias sucessivos. Foram aplicados 84,84mg N planta-1 na forma de (15NH42SO4 . As plantas foram colhidas em sete épocas diferentes. Após a colheita, as plantas foram fracionadas em folhas, enxerto, porta-enxerto, raízes grossas (>2mm e raízes finas (The foliar application of nitrogen before the leaves senescence may be a strategy to increase the nutrient reserves in the perennial parts, being available in the beginning of the vegetative growth of the annual parts. The objective of this work was to estimate the uptake and redistribution of N applied by foliar way in young grapevines. The experiment was carried out in a greenhouse at EMBRAPA-Grape and Wine, Bento Gonçalves Southern Brazil. The cultivars used were Chardonnay and Riesling Italic grafted on rootstock 101-14 Mgt. It was cultivated one plant by vase with 10kg of soil Udorthent. The foliar application of N was parceled in three times during three successive days. It was applied 84,84mg N plant-1 using (15NH42SO4 . The plants were collected in seven times, during vegetative growth. The plants were fractionated in leaves, graft, carry-graft, thick roots (>2mm and fine roots (<2mm, oven-dried, weighted, and analyzed N-total and 15N contents. The

The pattern of shikimate pathway and phenylpropanoids after inhibition by glyphosate or quinate feeding in pea roots.

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Zabalza, Ana; Orcaray, Luis; Fernández-Escalada, Manuel; Zulet-González, Ainhoa; Royuela, Mercedes

2017-09-01

The shikimate pathway is a metabolic route for the biosynthesis of aromatic amino acids (AAAs) (i.e. phenylalanine, tyrosine, and tryptophan). A key enzyme of shikimate pathway (5-enolpyruvylshikimate-3-phosphate synthase, EPSPS) is the target of the widely used herbicide glyphosate. Quinate is a compound synthesized in plants through a side branch of the shikimate pathway. Glyphosate provokes quinate accumulation and exogenous quinate application to plants shows a potential role of quinate in the toxicity of the herbicide glyphosate. Based on this, we hypothesized that the role of quinate accumulation in the toxicity of the glyphosate would be mediated by a deregulation of the shikimate pathway. In this study the effect of the glyphosate and of the exogenous quinate was evaluated in roots of pea plants by analyzing the time course of a full metabolic map of several metabolites of shikimate and phenylpropanoid pathways. Glyphosate application induced an increase of the 3-deoxy-D-arabino-heptulosonate-7-phosphate synthase (DAHPS, first enzyme of the shikimate pathway) protein and accumulation of metabolites upstream of the enzyme EPSPS. No common effects on the metabolites and regulation of shikimate pathway were detected between quinate and glyphosate treatments, supporting that the importance of quinate in the mode of action of glyphosate is not mediated by a common alteration of the regulation of the shikimate pathway. Contrary to glyphosate, the exogenous quinate supplied was probably incorporated into the main trunk from the branch pathway and accumulated in the final products, such as lignin, concomitant with a decrease in the amount of DAHPS protein. Copyright © 2016 Elsevier B.V. All rights reserved.

Diagnosing foliar nutrient dynamics of Eucalyptus grandis in ...

African Journals Online (AJOL)

Fertilisation is one of the most cost-effective methods of increasing and maintaining the productivity of Eucalyptus grandis plantations in South Africa. This silvicultural practice can be optimised by using the foliar nutrient ratios measured in plants at maximum growth as a guideline for fertiliser application. The foliar nutrient ...

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

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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)

Controle químico de biótipos de buva (Conyza canadensis e Conyza bonariensis resistentes ao glyphosate Chemical Control of glyphosate-resistant horseweed (Conyza Canadensis and hairy fleabane (Conyza bonariensis biotypes

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Micheli Satomi Yamauti

2010-09-01

Full Text Available Estudos foram conduzidos na Estação Experimental de Citricultura de Bebedouro, SP para avaliar a resposta de biótipos de buva resistentes aos herbicidas glyphosate, bromacil + diuron, diuron e paraquat isolados e em mistura, e o efeito de uma aplicação seqüencial com glyphosate. O delineamento foi o de blocos casualizados com quatro repetições e sete tratamentos.. Os herbicidas foram aplicados com pulverizador costal, à pressão constante (mantido por CO2 comprimido, munido com barra com três bicos do tipo TT110015 com um consumo de calda equivalente a 150 L ha-1. O controle foi avaliado visualmente, através de escala percentual de notas. Para o controle geral das plantas daninhas os melhores resultados foram obtidos com diuron isolado e com glyphosate em mistura com bromacil + diuron, enquanto para o controle da buva não houve diferença entre os tratamentos. Depois da aplicação seqüencial, o melhor tratamento para o controle de buva foi com diuron e bromacil+diuron.Studies were conducted at Estação Experimental de Citricultura de Bebedouro, SP to evaluate the response of glyphosate-resistant horseweed and hairy fleabane biotypes to herbicides glyphosate, bromacil + diuron, diuron e paraquat isolated and in mixture and effect of a sequential application of glyphosate. The experimental design was of complete randomized blocks with four replication and seven treatments. The herbicides were applied with costal sprayer, constant pressure with three nozzles TT110015, the equivalent spray volume was 150 L ha-1. The control was visually evaluated, trough percentile note scale. The best results were obtained to general control of weed with diuron isolated and glyphosate in mixture with bromacil + diuron while to glyphosate-resistant horseweed and hairy fleabane there was no difference between the treatments. After sequential application to Conyza sp control, the best treatment was obtained associated with diuron and bromacil+diuron.

Metabolic profiling of goldfish (Carassius auratis) after long-term glyphosate-based herbicide exposure.

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Li, Ming-Hui; Ruan, Ling-Yu; Zhou, Jin-Wei; Fu, Yong-Hong; Jiang, Lei; Zhao, He; Wang, Jun-Song

2017-07-01

Glyphosate is an efficient herbicide widely used worldwide. However, its toxicity to non-targeted organisms has not been fully elucidated. In this study, the toxicity of glyphosate-based herbicide was evaluated on goldfish (Carassius auratus) after long-term exposure. Tissues of brains, kidneys and livers were collected and submitted to NMR-based metabolomics analysis and histopathological inspection. Plasma was collected and the blood biochemical indexes of AST, ALT, BUN, CRE, LDH, SOD, GSH-Px, GR and MDA were measured. Long-term glyphosate exposure caused disorders of blood biochemical indexes and renal tissue injury in goldfish. Metabolomics analysis combined with correlation network analysis uncovered significant perturbations in oxidative stress, energy metabolism, amino acids metabolism and nucleosides metabolism in glyphosate dosed fish, which provide new clues to the toxicity of glyphosate. This integrated metabolomics approach showed its applicability in discovering the toxic mechanisms of pesticides, which provided new strategy for the assessment of the environmental risk of herbicides to non-target organisms. Copyright © 2017 Elsevier B.V. All rights reserved.

Glyphosate-Resistant Goosegrass from Mississippi

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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.

Carfentrazone-ethyl, isolado e associado a duas formulações de glyphosate no controle de duas espécies de trapoeraba Carfentrazone-ethyl isolated and in mixture with two glyphosate formulations on the control of two dayflower species

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C.P. Ronchi

2002-04-01

parte aérea provocada pelos herbicidas.This research was conducted to evaluate the effectiveness of carfentrazone-ethyl, isolated and in mixture with to glyphosate or glyphosate-potassium salt, on controlling two dayflower species, Commelina diffusa and C. benghalensis. These species were grown from stem segments in 12 L pots filled with soil, during 120 days. A complete randomized block design with four replicates was performed for each species. The treatments were carfentrazone-ethyl (0, 10, 20, 30, 40 and 50 g ha-1, isolated and in mixture with glyphosate or glyphosate-potassium salt, these being applied at doses of 720 g ha-1. The percentages of weed control and shoot fresh weight (SFW were evaluated. C. diffusa was more tolerant to carfentrazone-ethyl alone or combined with both glyphosate and glyphosate-potassium salt than C. benghalensis. Both glyphosate and glyphosate-potassium salt were inefficient (control below 30% when applied isolated, regardless of the species. The efficiency of controlling herbicide mixtures was greater than their single applications, except for the carfentrazone-ethyl in doses above 30 g ha-1, with C. benghalensis, in which control was similar to the employed mixtures. Despite the reasonable control (from 71 to 80% for C. diffusa and the very good control (above 81% for C. benghalensis, obtained with carfentrazone-ethyl + glyphosate or carfentrazone-ethyl + glyphosate-potassium salt mixtures, a sole application did not decisively control Commelina spp. In effect, recovery of plants as seen through SFW evaluation took place irrespective of the species; moreover, for C. benghalensis, reinfestation from underground seeds that became viable after the shoot's death, due to herbicide application, was also found.

Foliar Application of Potassium Fertilizer to Reduce the Effects of Salinity in Potato

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H Molahoseini

2017-06-01

Full Text Available Introduction The potato of commerce (Solanum tuberosum L. is an annual dicot species. It is an autotetraploid with 4x=48 chromosomes. In Iran the consumption per capita of potato is over the 35 kg. Potato production is usually done without reducing yield in the irrigation water salinity 1-2 dS m-1, but 4.2 dS m-1 salinity reduces yield by 26 percent. 10, 25 and 50 percent yield reduction have been reported in soil electrical conductivity 2.5, 3.8 and 5.9 dS m-1, respectively . Between the ability of plant species to maintain potassium levels and their tolerance to salinity is positive correlation and on this basis nutritional irregularity due to increased salinity can be compensated by increasing of potassium fertilizer. In tolerant plant species, during times of increased salinity, selective absorption of potassium increased. The ability of plants to maintain a certain level of K/Na within the cell is essential for salt tolerance and sometimes of these ratios is used as indicators of salinity tolerance. Potato yield in response to salt stress, according to a variety of uses, can be reduced from 20 to 85 percent. Harmful effects of salinity in the beginning stages of tubers and tuber growth stage are important, therefore, tuber number and tuber size are two important components of yield which may reduce in the effect of salinity. Accelerate the aging process of the shoot, unwanted earliness, are of the reasons for the reduction in tuber size. Materials and Methods A field experiment was conducted in the agricultural and natural resources research center (31° 32´ N, 51° 51´ E, Isfahan, Islamic Republic of Iran. According to twenty years statistics, rainfall and temperature means for experiment location were 110 mm and 25 °C, respectively. The experiment was conducted as a factorial in a completely randomized block design with four replications. The treatments were three levels of foliar K application (control, K sulphate 10 ppm, and 2.5 ppm

Increasing Selenium and Yellow Pigment Concentrations in Foxtail Millet (Setaria italica L.) Grain with Foliar Application of Selenite.

Science.gov (United States)

Ning, Na; Yuan, Xiang-Yang; Dong, Shu-Qi; Wen, Yin-Yuan; Gao, Zhen-Pan; Guo, Mei-Jun; Guo, Ping-Yi

2016-03-01

Although addition of selenium (Se) is known to increase Se in crops, it is unclear whether exogenous Se is linked to nutritional and functional components in foxtail millet (Setaria italica L.). In this study, we examined the potential of increasing Se and yellow pigment (YP) in foxtail millet grain by foliar application of Se. Field experiments were conducted during the growing season of foxtail millet in 2013 and 2014 to assess the effects of foliar spray of sodium selenite (10-210 g Se ha(-1)) on the yield, Se uptake and accumulation, total YP, and microminerals in the grain. Average grain yields with Se application were 5.60 and 4.53 t ha(-1) in the 2 years, showing no significant differences from the unfertilized control. However, grain Se concentration increased linearly with Se application rate, by 8.92 and 6.09 μg kg(-1) in the 2 years with application of 1 g Se ha(-1) (maximum grain recovery rates of Se fertilizer, 52 and 28 %). Likewise, total grain YP concentration markedly increased by 0.038 and 0.031 mg kg(-1) in the 2 years with application of 1 g Se ha(-1). Grain Mn, Cu, Fe, and Zn concentrations were not significantly affected by Se application. This study indicated that foliar application of Se effectively and reliably increased the concentrations of Se and YP in foxtail millet grain without affecting the yield or mineral micronutrient concentrations. Thus, foliar-applied selenite has a significant potential to increase the concentrations of selenium and YP (putative lutein (Shen, J Cereal Sci 61:86-93, 2015; Abdel-Aal, Cereal Chem 79:455-457, 2002; Abdel-Aal, J Agric Food Chem 55:787-794, 2007)) of foxtail millet and, thus, the health benefits of this crop.

Effects of glyphosate acid and the glyphosate-commercial formulation (Roundup) on Dimorphandra wilsonii seed germination: Interference of seed respiratory metabolism.

Science.gov (United States)

Gomes, Marcelo Pedrosa; da Silva Cruz, Fernanda Vieira; Bicalho, Elisa Monteze; Borges, Felipe Viègas; Fonseca, Marcia Bacelar; Juneau, Philippe; Garcia, Queila Souza

2017-01-01

Glyphosate-formulations are widely used in the Brazilian Cerrado (neotropical savanna) with little or no control, threatening population of the endangered species Dimorphandra wilsonii. We investigated the toxicity of different concentrations (0, 5, 25 and 50 mg l -1 ) of glyphosate acid and one of its formulations (Roundup ® ) on seed germination in D. wilsonii. Glyphosate acid and Roundup drastically decreased seed germination by decreasing seed respiration rates. The activation of antioxidant enzymes, ascorbate peroxidase and catalase assure no hydrogen peroxide accumulation in exposed seeds. Glyphosate acid and the Roundup-formulation negatively affected the activities of enzymes associated with the mitochondrial electron transport chain (ETC), with Complex III as its precise target. The toxicity of Roundup-formulation was greater than that of glyphosate acid due to its greater effects on respiration. The herbicide glyphosate must impair D. wilsonii seed germination by disrupting the mitochondrial ETC, resulting in decreased energy (ATP) production. Our results therefore indicate the importance of avoiding (or closely regulating) the use of glyphosate-based herbicides in natural Cerrado habitats of D. wilsonni as they are toxic to seed germination and therefore threaten conservation efforts. It will likewise be important to investigate the effects of glyphosate on the seeds of other species and to investigate the impacts of these pesticides elsewhere in the world. Copyright © 2016 Elsevier Ltd. All rights reserved.

[Glyphosate--a non-toxic pesticide?].

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Pieniazek, Danuta; Bukowska, Bozena; Duda, Wirgiliusz

2003-01-01

Glyphosate is currently the most commonly applied herbicide and its use is still growing. Nowadays, over 50 commercial preparations containing this compound are used, and these formulations are much more toxic than their active compound, glyphosate, owing to the presence of many surfactants and carrier compounds. Toxicological investigations provide evidence that glyphosate is an extremely "safe" herbicide for animals. This is why its use in agriculture is universal. In June 1991, the Environmental Protection Agency (EPA) categorized this compound into class E (according to EPA there are five categories of carcinogenicity), which means that it is probably not carcinogenic to humans. Unfortunately, the study carried out by Swedish oncologists in 2001 showed that glyphosate may induce cancer of the lymphatic system. The results of the Swedish study have changed our opinion about "safety" of this herbicide. Investigations concerning both its accumulation and toxic effect in animals and plants are now under way in many laboratories.

Genotoxicity Expert Panel review: weight of evidence evaluation of the genotoxicity of glyphosate, glyphosate-based formulations, and aminomethylphosphonic acid.

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Brusick, David; Aardema, Marilyn; Kier, Larry; Kirkland, David; Williams, Gary

2016-09-01

In 2015, the International Agency for Research on Cancer (IARC) published a monograph concluding there was strong evidence for genotoxicity of glyphosate and glyphosate formulations and moderate evidence for genotoxicity of the metabolite aminomethylphosphonic acid (AMPA). These conclusions contradicted earlier extensive reviews supporting the lack of genotoxicity of glyphosate and glyphosate formulations. The IARC Monograph concluded there was strong evidence of induction of oxidative stress by glyphosate, glyphosate formulations, and AMPA. The Expert Panel reviewed the genotoxicity and oxidative stress data considered in the IARC Monograph, together with other available data not considered by IARC. The Expert Panel defined and used a weight of evidence (WoE) approach that included ranking of studies and endpoints by the strength of their linkage to events associated with carcinogenic mechanisms. Importantly, the Expert Panel concluded that there was sufficient information available from a very large number of regulatory genotoxicity studies that should have been considered by IARC. The WoE approach, the inclusion of all relevant regulatory studies, and some differences in interpretation of individual studies led to significantly different conclusions by the Expert Panel compared with the IARC Monograph. The Expert Panel concluded that glyphosate, glyphosate formulations, and AMPA do not pose a genotoxic hazard and the data do not support the IARC Monograph genotoxicity evaluation. With respect to carcinogenicity classification and mechanism, the Expert Panel concluded that evidence relating to an oxidative stress mechanism of carcinogenicity was largely unconvincing and that the data profiles were not consistent with the characteristics of genotoxic carcinogens.

Transfer of glyphosate and its degradate AMPA to surface waters through urban sewerage systems.

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Botta, Fabrizio; Lavison, Gwenaëlle; Couturier, Guillaume; Alliot, Fabrice; Moreau-Guigon, Elodie; Fauchon, Nils; Guery, Bénédicte; Chevreuil, Marc; Blanchoud, Hélène

2009-09-01

A study of glyphosate and aminomethyl phosphonic acid (AMPA) transfer in the Orge watershed (France) was carried out during 2007 and 2008. Water samples were collected in surface water, wastewater sewer, storm sewer and wastewater treatment plant (WWTP). These two molecules appeared to be the most frequently detected ones in the rivers and usually exceeded the European quality standard concentrations of 0.1microg L(-1) for drinking water. The annual glyphosate estimated load was 1.9 kg year(-1) upstream (agricultural zone) and 179.5 kg year(-1) at the catchment outlet (urban zone). This result suggests that the contamination of this basin by glyphosate is essentially from urban origin (road and railway applications). Glyphosate reached surface water prevalently through storm sewer during rainfall event. Maximum concentrations were detected in storm sewer just after a rainfall event (75-90 microg L(-1)). High concentrations of glyphosate in surface water during rainfall events reflected urban runoff impact. AMPA was always detected in the sewerage system. This molecule reached surface water mainly via WWTP effluent and also through storm sewer. Variations in concentrations of AMPA during hydrological episodes were minor compared to glyphosate variations. Our study highlights that AMPA and glyphosate origins in urban area are different. During dry period, detergent degradation seemed to be the major AMPA source in wastewater.

Glyphosate catabolism by Pseudomonas sp

International Nuclear Information System (INIS)

Shinabarger, D.L.

1986-01-01

The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing [3- 14 C] glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO 2 . Fractionation of stationary phase cells labeled with [3- 14 C]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- 14 C]glyphosate revealed that [3- 14 C]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

Occurrence and fate of the herbicide glyphosate and its degradate aminomethylphosphonic acid in the atmosphere

Science.gov (United States)

Chang, Feng-Chih; Simcik, M.F.; Capel, P.D.

2011-01-01

This is the first report on the ambient levels of glyphosate, the most widely used herbicide in the United States, and its major degradation product, aminomethylphosphonic acid (AMPA), in air and rain. Concurrent, weekly integrated air particle and rain samples were collected during two growing seasons in agricultural areas in Mississippi and Iowa. Rain was also collected in Indiana in a preliminary phase of the study. The frequency of glyphosate detection ranged from 60 to 100% in both air and rain. The concentrations of glyphosate ranged from 3 and from <0.1 to 2.5 µg/L in air and rain samples, respectively. The frequency of detection and median and maximum concentrations of glyphosate in air were similar or greater to those of the other high-use herbicides observed in the Mississippi River basin, whereas its concentration in rain was greater than the other herbicides. It is not known what percentage of the applied glyphosate is introduced into the air, but it was estimated that up to 0.7% of application is removed from the air in rainfall. Glyphosate is efficiently removed from the air; it is estimated that an average of 97% of the glyphosate in the air is removed by a weekly rainfall ≥30 mm.

ASSOCIATION OF PESTICIDES WITH SOYBEAN LEAF MICRONUTRIENTS CONTENTS AND SEEDS YIELD AND PHYSIOLOGIC QUALITY ASSOCIAÇÃO DE AGROTÓXICOS AOS TEORES FOLIARES DE MICRONUTRIENTES E À PRODUTIVIDADE E QUALIDADE FISIOLÓGICA DE SEMENTES DE SOJA

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André Cabral França

2011-10-01

Full Text Available

Glyphosate effects on leaf micronutrients contents of transgenic soybean have been widely reported, however, little is known about these effects associated with other pesticides. The objective of this study was to evaluate the physiologic quality and yield of soybean seeds, as well as leaf micronutrients contents, according to weed control methods. Ten RBD treatments were arranged in a split-plot scheme with four replications. The application or non-application of endosulphan + tebuconazole was evaluated in the plots, while the weeds control methods were assessed in the subplots (weeded control; non-weeded control; single application of glyphosate (1,080 g ha^-1 and fomesafen + fluazifop-?-butil (180 + 225 g ha^-1, both at 15 DAE; and sequential application of glyphosate (1,080 g ha^-1 at 15, 30, and 45 DAE. After harvesting, the soybean seeds were sampled, in order to evaluate their germination, vigor, and yield. Copper and manganese contents were only influenced by the sequential application of glyphosate, associated with endosulphan + tebuconazole. The cold test germination was reduced in seeds of plants treated with fomesafen + fluazifop-p-butil associated with endosulphan + tebuconazole. Among the treatments without endosulphan + tebuconazole, the sequential application of glyphosate promoted the highest 100-seeds weight, as well as, when associated with endosulphan + tebuconazole, reduced the leaf concentrations of Cu and Mn, however, it improved seeds germination and showed no effects on seeds vigor, when compared with the weeded soybean.

Influence of palm oil on the efficacy of glyphosate in the control of Cyperus rotondus L

International Nuclear Information System (INIS)

Mohamad, R.B.; Dzolkhifli Omar

1998-01-01

The influence of the addition of palm oil to the formulation on the efficacy of glyphosate for the control of Cyperus rotundus was evaluated in the laboratory, glass-house and field. Triton X-100 failed to maintain a stable emulsion of palm oil in the formulation 10 minutes after mixing. In glass-house experiments adding mineral oil and palm oil to the glyphosate spray mixture did not increase the herbicidal efficacy. In general, glyphosate was more effective when sprayed at the volume application rate of 100 L/ha than at 400 L/ha. In contrast to the glass-house studies, in the field trial the addition of palm oil increased the efficacy of glyphosate. (author)

Electrochemical degradation and mineralization of glyphosate herbicide.

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Tran, Nam; Drogui, Patrick; Doan, Tuan Linh; Le, Thanh Son; Nguyen, Hoai Chau

2017-12-01

The presence of herbicide is a concern for both human and ecological health. Glyphosate is occasionally detected as water contaminants in agriculture areas where the herbicide is used extensively. The removal of glyphosate in synthetic solution using advanced oxidation process is a possible approach for remediation of contaminated waters. The ability of electrochemical oxidation for the degradation and mineralization of glyphosate herbicide was investigated using Ti/PbO 2 anode. The current intensity, treatment time, initial concentration and pH of solution are the influent parameters on the degradation efficiency. An experimental design methodology was applied to determine the optimal condition (in terms of cost/effectiveness) based on response surface methodology. Glyphosate concentration (C 0  = 16.9 mg L -1 ) decreased up to 0.6 mg L -1 when the optimal conditions were imposed (current intensity of 4.77 A and treatment time of 173 min). The removal efficiencies of glyphosate and total organic carbon were 95 ± 16% and 90.31%, respectively. This work demonstrates that electrochemical oxidation is a promising process for degradation and mineralization of glyphosate.

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

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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.

Efeito de formulações na absorção e translocação do glyphosate em soja transgênica Effect of formulations on the absorption and translocation of glyphosate in transgenic soybean

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J.B. Santos

2007-01-01

, 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.

Genetically transformed tobacco plants expressing synthetic EPSPS gene confer tolerance against glyphosate herbicide.

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Imran, Muhammad; Asad, Shaheen; Barboza, Andre Luiz; Galeano, Esteban; Carrer, Helaine; Mukhtar, Zahid

2017-04-01

Glyphosate quashes the synthesis of 5-enolpyruvylshikimate-3- phosphate synthase (EPSPS) enzyme which intercedes the functioning of shikimate pathway for the production of aromatic amino acids. Herbicide resistant crops are developed using glyphosate insensitive EPSPS gene isolated from Agrobacterium sp. strain CP4, which give farmers a sustainable weed control option. Intentions behind this study were to design and characterize the synthetic herbicide resistant CP4 - EPSPS gene in a model plant system and check the effectiveness of transformed tobacco against application of glyphosate. Putative transgenic plants were obtained from independent transformation events, and stable plant transformation, transgene expression and integration were demonstrated respectively by PCR, qRT-PCR and Southern hybridization. Gene transcript level and gene copy number (1-4) varied among the tested transgenic tobacco lines. Herbicide assays showed that transgenic plants were resistant to glyphosate after 12 days of spraying with glyphosate, and EPSPS activity remained at sufficient level to withstand the spray at 1000 ppm of the chemical. T 1 plants analyzed through immunoblot strips and PCR showed that the gene was being translated into protein and transmitted to the next generation successfully. This codon optimized synthetic CP4 - EPSPS gene is functionally equivalent to the gene for glyphosate resistance available in the commercial crops and hence we recommend this gene for transformation into commercial crops.

Glyphosate: cancerous or not? Perspectives from both ends of the debate

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Syeda Aamna Hassan

2017-08-01

Full Text Available Glyphosate is non-selective herbicide. Studies published in the last decade, point towards glyphosate toxicity. Shikimic acid pathway for the biosynthesis of folates and aromatic amino acids is inhibited by glyphosate. Glyphosate carcinogenicity is still considered to be a controversial issue. The World Health Organizations’ International Agency recently concluded that glyphosate is “probably carcinogenic to humans.” Some researchers believed that glyphosate is not linked with carcinogenicity.

Integrating soil conservation practices and glyphosate-resistant crops: impacts on soil.

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Locke, Martin A; Zablotowicz, Robert M; Reddy, Krishna N

2008-04-01

Conservation practices often associated with glyphosate-resistant crops, e.g. limited tillage and crop cover, improve soil conditions, but only limited research has evaluated their effects on soil in combination with glyphosate-resistant crops. It is assumed that conservation practices have similar benefits to soil whether or not glyphosate-resistant crops are used. This paper reviews the impact on soil of conservation practices and glyphosate-resistant crops, and presents data from a Mississippi field trial comparing glyphosate-resistant and non-glyphosate-resistant maize (Zea mays L.) and cotton (Gossypium hirsutum L.) under limited tillage management. Results from the reduced-tillage study indicate differences in soil biological and chemical properties owing to glyphosate-resistant crops. Under continuous glyphosate-resistant maize, soils maintained greater soil organic carbon and nitrogen as compared with continuous non-glyphosate-resistant maize, but no differences were measured in continuous cotton or in cotton rotated with maize. Soil microbial community structure based on total fatty acid methyl ester analysis indicated a significant effect of glyphosate-resistant crop following 5 years of continuous glyphosate-resistant crop as compared with the non-glyphosate-resistant crop system. Results from this study, as well as the literature review, indicate differences attributable to the interaction of conservation practices and glyphosate-resistant crop, but many are transient and benign for the soil ecosystem. Glyphosate use may result in minor effects on soil biological/chemical properties. However, enhanced organic carbon and plant residues in surface soils under conservation practices may buffer potential effects of glyphosate. Long-term field research established under various cropping systems and ecological regions is needed for critical assessment of glyphosate-resistant crop and conservation practice interactions. Copyright (c) 2008 by John Wiley & Sons

75 FR 24969 - Glyphosate From China

Science.gov (United States)

2010-05-06

... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-1178 (Preliminary)] Glyphosate From China AGENCY: United States International Trade Commission. ACTION: Notice of withdrawal of petition in... investigation concerning glyphosate from China (investigation No. 731-TA-1178 (Preliminary)) is discontinued...

75 FR 17768 - Glyphosate From China

Science.gov (United States)

2010-04-07

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

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

International Nuclear Information System (INIS)

Shieh, Wenjang; Geiger, D.R.

1990-01-01

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 14 CO 2 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 14 C 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

Determine the Optimal Levels of Bio-fertilizers and Foliar Application of Iron on Yield and Quality Indices of Roselle (Hibiscus sabdariffa L.

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zahra mir

2018-02-01

Full Text Available Introduction In conventional agricultural systems to obtain the highest performance continuous use of chemical fertilizers is inevitable. The health of the plant, soil and living matter depends on the rotation of food elements in the ecosystem. This cycle is disrupted as a result of the loss of soil fertility, its food imbalance and inappropriate cultivation practices. Bio-fertilizers are composed of beneficial microorganisms, each for a specific purpose, such as nitrogen fixation, release of phosphate ions, potassium, iron. It should be noted that most studies in the field for sour Roselle (Hibiscus sabdariffa are based on the use of various chemical fertilizers, but the reaction of this plant to bio-fertilizers and iron solubilization has not been considered. Therefore, this study aimed to investigate the effect of bio fertilizers and iron on yield and quality traits of Roselle in hot and dry weather conditions. Materials and Methods In order to investigate the effects of bio-fertilizers and foliar application iron on yield and quality indicators Roselle (Hibiscus sabdariffa experiment in Research field of Zabol University Agriculture Institute in 2015-2016 years was performed with split-plot based on completely randomized design and three replications. Treatments consisted of four levels of bio-fertilizers: control (without fertilizer, vermicompost, cow manure, seaweed and iron foliar applications include: lack of iron, foliar application at a rate of 3cc per thousand, 6cc per thousand was considered. As a source of bio-fertilizer treatments and foliar application iron levels were considered as sub plots. Before sowing Roselle seeds, vermicompost and manure were added to the soil and inoculation operation . Measurements were: economic yield, biological yield, harvest index, chlorophyll a, b and carotenoids, anthocyanins, carbohydrates and protein. Statistical analysis of data was done with SAS software version 9.1 and mean comparison with

Probability of foliar injury for Acer sp. based on foliar fluoride concentrations.

Science.gov (United States)

McDonough, Andrew M; Dixon, Murray J; Terry, Debbie T; Todd, Aaron K; Luciani, Michael A; Williamson, Michele L; Roszak, Danuta S; Farias, Kim A

2016-12-01

Fluoride is considered one of the most phytotoxic elements to plants, and indicative fluoride injury has been associated over a wide range of foliar fluoride concentrations. The aim of this study was to determine the probability of indicative foliar fluoride injury based on Acer sp. foliar fluoride concentrations using a logistic regression model. Foliage from Acer nedundo, Acer saccharinum, Acer saccharum and Acer platanoides was collected along a distance gradient from three separate brick manufacturing facilities in southern Ontario as part of a long-term monitoring programme between 1995 and 2014. Hydrogen fluoride is the major emission source associated with the manufacturing facilities resulting with highly elevated foliar fluoride close to the facilities and decreasing with distance. Consistent with other studies, indicative fluoride injury was observed over a wide range of foliar concentrations (9.9-480.0 μg F -  g -1 ). The logistic regression model was statistically significant for the Acer sp. group, A. negundo and A. saccharinum; consequently, A. negundo being the most sensitive species among the group. In addition, A. saccharum and A. platanoides were not statistically significant within the model. We are unaware of published foliar fluoride values for Acer sp. within Canada, and this research provides policy maker and scientist with probabilities of indicative foliar injury for common urban Acer sp. trees that can help guide decisions about emissions controls. Further research should focus on mechanisms driving indicative fluoride injury over wide ranging foliar fluoride concentrations and help determine foliar fluoride thresholds for damage.

Glyphosate in Irish adults - A pilot study in 2017.

Science.gov (United States)

Connolly, Alison; Leahy, Michelle; Jones, Kate; Kenny, Laura; Coggins, Marie A

2018-05-02

Glyphosate is the highest volume herbicide used globally and has recently been classified as a 2 A 'probably carcinogenic to humans' by the International Agency for Research on Cancer (IARC). There is limited data to evaluate the public health impacts from glyphosate exposure. The objective of this study is to conduct an exploratory glyphosate exposure assessment study among Irish adults, who were non-occupational users of glyphosate. A convenient sampling method was used, collecting one first morning void spot urine sample from each participant. A biomonitoring survey involving the collection and analysis of 20 ml spot urine samples from 50 Irish adults was conducted in June 2017. Participants completed a short questionnaire to collect information on demographics, dietary habits and lifestyle. Glyphosate was extracted using solid phase extraction (SPE) and analysed by liquid chromatography tandem mass spectrometry (LC-MC/MS). Of the 50 urine samples analysed, 10 (20%) contained detectable levels of glyphosate (0.80-1.35 µg L -1 ). Exposure concentrations are higher than those reported in comparable studies of European and American adults. Glyphosate was detectable in 20% of the samples collected from Irish adults. The low proportion of detectable glyphosate levels could be due to lower localised use of pesticides, having a small sample size or the higher analytical detection limit used in this study (0.5 µg L -1 ), which could underestimate the true exposure and warrants further investigation. Given the widespread use of glyphosate, further information on population exposure is required to advance our understanding of the relationship between chronic low dose exposure to glyphosate and human health risk. Copyright © 2018 Elsevier Inc. All rights reserved.

Mechanism of Resistance to Glyphosate in Lolium perenne from Argentina

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Marcos Yanniccari

2017-10-01

Full Text Available In Argentina, glyphosate resistance was reported in a Lolium perenne population after 12 years of successful herbicide use. The aim of the current paper was to put in evidence for the mechanism of glyphosate resistance of this weed. Susceptible leaves treated with different doses of glyphosate and incubated in vitro showed an accumulation of shikimic acid of around three to five times the basal level, while no changes were detected in leaves of glyphosate-resistant plants. The resistance mechanism prevents shikimate accumulation in leaves, even under such tissue-isolation conditions. The activity of the glyphosate target enzyme (EPSPS: 5-enolpyruvylshikimate-3-phosphate synthase was quantified at different herbicide concentrations. EPSPS from resistant plants showed no difference in glyphosate-sensitivity compared to EPSPS from susceptible plants, and, accordingly, no amino acid substitution causing mutations associated with resistance were found. While the glyphosate target enzymes were equally sensitive, the basal EPSPS activity in glyphosate resistant plants was approximately 3-fold higher than the EPSPS activity in susceptible plants. This increased EPSPS activity in glyphosate resistant plants was associated with a 15-fold higher expression of EPSPS compared with susceptible plants. Therefore, the over-expression of EPSPS appears to be the main mechanism responsible for resistance to glyphosate. This mechanism has a constitutive character and has important effects on plant fitness, as recently reported.

Glyphosate induces human breast cancer cells growth via estrogen receptors.

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Thongprakaisang, Siriporn; Thiantanawat, Apinya; Rangkadilok, Nuchanart; Suriyo, Tawit; Satayavivad, Jutamaad

2013-09-01

Glyphosate is an active ingredient of the most widely used herbicide and it is believed to be less toxic than other pesticides. However, several recent studies showed its potential adverse health effects to humans as it may be an endocrine disruptor. This study focuses on the effects of pure glyphosate on estrogen receptors (ERs) mediated transcriptional activity and their expressions. Glyphosate exerted proliferative effects only in human hormone-dependent breast cancer, T47D cells, but not in hormone-independent breast cancer, MDA-MB231 cells, at 10⁻¹² to 10⁻⁶M in estrogen withdrawal condition. The proliferative concentrations of glyphosate that induced the activation of estrogen response element (ERE) transcription activity were 5-13 fold of control in T47D-KBluc cells and this activation was inhibited by an estrogen antagonist, ICI 182780, indicating that the estrogenic activity of glyphosate was mediated via ERs. Furthermore, glyphosate also altered both ERα and β expression. These results indicated that low and environmentally relevant concentrations of glyphosate possessed estrogenic activity. Glyphosate-based herbicides are widely used for soybean cultivation, and our results also found that there was an additive estrogenic effect between glyphosate and genistein, a phytoestrogen in soybeans. However, these additive effects of glyphosate contamination in soybeans need further animal study. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of the herbicide glyphosate on the uptake of 239Pu and 241Am to vegetation

International Nuclear Information System (INIS)

Nisbet, A.F.; Shaw, S.

1990-01-01

Glyphosate (n-phosphonomethyl glycine) is a broad spectrum herbicide widely used in lowland agriculture, forestry and improved upland pastures. Although its metal chelating properties are well established, its interaction with radionuclides remains unknown. A pot experiment was conducted to determine the effect of soil applications of glyphosate on the uptake of 239 Pu and 241 Am to peas and carrots grown in loam, peat and sand soils. Soil-to-plant transfer factors were calculated for treated and untreated soils at harvest. The most marked effect was an increase in 241 Am uptake to crops grown in loam soil. Supplementary laboratory batch experiments were conducted by shaking radiolabelled soil and its associated soil solution with glyphosate. The activity concentration of 241 Am increased ten fold in the liquid phase of loam soils treated with glyphosate. It is postulated that this 241 Am desorption could have been mediated by the formation of a stable Am-glyphosate complex which was subsequently more available for crop uptake than Am alone. (author)

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

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O.M. Yamashita

2006-09-01

-month-old plants by observing plant toxicity, plant height, stem diameter, and leaf number. A control was also used without herbicide application to compare the effects. Under the conditions of this experiment, Varjão presented tolerance to and ability to recover from glyphosate up to the rate of 360 g ha-1. Higher rates delayed plant development. The damage caused by glyphosate drift in these plants was directly proportional to rate increase. The symptoms included leaf fall, compromising plant growth.

78 FR 60707 - Glyphosate; Pesticide Tolerances

Science.gov (United States)

2013-10-02

... chromatography/mass spectrometry/mass spectrometry Method 15444) is available to enforce the tolerance expression...) 566-1744, and the telephone number for the OPP Docket is (703) 305- 5805. Please review the visitor...-acetyl-glyphosate (expressed as glyphosate equivalents). VI. Statutory and Executive Order Reviews This...

Assessment of the levels of N- (Phosphonomethyl) glycine glyphosate in selected glyphosate-based herbicides on the Ghanaian market

International Nuclear Information System (INIS)

Iddrisu, Adisatu

2016-07-01

Sixty one (61) samples of Glyphosate based herbicides were collected from the central commercial hub of Kumasi (Kejetia) and ware houses of importers in Ashanti and Greater Accra regions of Ghana and analyzed using high performance liquid chromatography (HPLC). Information about the efficacy of the numerous Glyphosate herbicides on the market was also collected by way of questionnaire. Results of the analysis indicated that only ten (16.4 %) out of the sixty one samples met the Environmental Protection Agency’s requirement of ±5 % of the stated active ingredient concentration and 51 samples representing 83.6 % were all out of the acceptable range. Active ingredient was either understated or overstated. About 21.6 % of the samples that failed to meet requirements were overstated and 78.4 % were understated. Apart from a few of the samples that had concentrations higher than stated label claims with 69 g/L (19.2 %) highest, most samples were generally lower than stated label claims. Some (G09, G18 and G44) samples contained virtually no active ingredient with shortfalls as high as 98.6%. Some of these shortfalls explained findings from the field investigations where some respondents complained of Glyphosate not being efficacious. Farmers may follow the application and safety instructions but this only holds true as long as the herbicides provide efficient control of weed. This can only be achieved with products of consistently high quality. This study also discovered that, there was no possibility of adulteration of the herbicide along the value chain as results for products picked from ware houses of importers did not differ much from those picked from the open market. Results from the other method employed in Glyphosate determination was UV/VIV spectroscopy, this method is simpler and faster and readily available in most laboratories in Ghana. Results from UV/VIS were comparable to that of the HPLC with generally lower values for UV/VIS readings. It is therefore

Behavior of Foliares Applications of Humus Mixed with the NPK in Rice Cultivation (Oryza Sativa L..

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Rolando Saborit Reyes

2013-12-01

Full Text Available Taking into consideration the observation of one green yellowsh clorosis in the plantations of rice, after the cold campaings and the disminishing of the agricultural efficiency of the cerial in areas of Saint Elena Land belonging to the fortified cooperatove of credits and service (FCCS Camilo Cienfuegos in Las Nuevas, La Sierpe, Province of Sancti – Spiritus, were done foliars aplications with mineral fertilizing as, N.P.K to different doses and moments of applications, in order to obtain alternative of nutrition for the cultivation, the work was done on a green yellowish ferralitic ground since 2009 to 2011, using LP-5 cultivation doing the sowing by the method of transplantation, fertilization. It was done mixing 49L. ha-¹ of liquid warm humus with 0.35 Kg. ha-¹ of nitrogen, phosphorus and potassium. The results shown that the use of the foliar fertilization with liquid worm humus mixed with the N.P.K minerals, increased the efficiency, obtaining 5.3t. ha-¹ as an average in different variants used. The economic analysis showed that the treatment with 40% of nitrogen was reduced with seven foliars applications, it was highest to the witness N.P.K in 1.5t . ha-¹ of the grain obtaining a relative benefit of 4264.55 pesos by hectarea.

Airborne remote sensing assessment of the damage to cotton caused by spray drift from aerially applied glyphosate through spray deposition measurements

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Off-target drift of aerially applied glyphosate can cause plant injury, which is of great concern to farmers and aerial applicators. To determine the extent of crop injury due to near-field drift, an experiment was conducted with a single aerial application of glyphosate. For identification of the d...

Improving Glyphosate Oxidation Activity of Glycine Oxidase from Bacillus cereus by Directed Evolution

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Zhan, Tao; Zhang, Kai; Chen, Yangyan; Lin, Yongjun; Wu, Gaobing; Zhang, Lili; Yao, Pei; Shao, Zongze; Liu, Ziduo

2013-01-01

Glyphosate, a broad spectrum herbicide widely used in agriculture all over the world, inhibits 5-enolpyruvylshikimate-3-phosphate synthase in the shikimate pathway, and glycine oxidase (GO) has been reported to be able to catalyze the oxidative deamination of various amines and cleave the C-N bond in glyphosate. Here, in an effort to improve the catalytic activity of the glycine oxidase that was cloned from a glyphosate-degrading marine strain of Bacillus cereus (BceGO), we used a bacteriophage T7 lysis-based method for high-throughput screening of oxidase activity and engineered the gene encoding BceGO by directed evolution. Six mutants exhibiting enhanced activity toward glyphosate were screened from two rounds of error-prone PCR combined with site directed mutagenesis, and the beneficial mutations of the six evolved variants were recombined by DNA shuffling. Four recombinants were generated and, when compared with the wild-type BceGO, the most active mutant B3S1 showed the highest activity, exhibiting a 160-fold increase in substrate affinity, a 326-fold enhancement in catalytic efficiency against glyphosate, with little difference between their pH and temperature stabilities. The role of these mutations was explored through structure modeling and molecular docking, revealing that the Arg51 mutation is near the active site and could be an important residue contributing to the stabilization of glyphosate binding, while the role of the remaining mutations is unclear. These results provide insight into the application of directed evolution in optimizing glycine oxidase function and have laid a foundation for the development of glyphosate-tolerant crops. PMID:24223901

Improving glyphosate oxidation activity of glycine oxidase from Bacillus cereus by directed evolution.

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Tao Zhan

Full Text Available Glyphosate, a broad spectrum herbicide widely used in agriculture all over the world, inhibits 5-enolpyruvylshikimate-3-phosphate synthase in the shikimate pathway, and glycine oxidase (GO has been reported to be able to catalyze the oxidative deamination of various amines and cleave the C-N bond in glyphosate. Here, in an effort to improve the catalytic activity of the glycine oxidase that was cloned from a glyphosate-degrading marine strain of Bacillus cereus (BceGO, we used a bacteriophage T7 lysis-based method for high-throughput screening of oxidase activity and engineered the gene encoding BceGO by directed evolution. Six mutants exhibiting enhanced activity toward glyphosate were screened from two rounds of error-prone PCR combined with site directed mutagenesis, and the beneficial mutations of the six evolved variants were recombined by DNA shuffling. Four recombinants were generated and, when compared with the wild-type BceGO, the most active mutant B3S1 showed the highest activity, exhibiting a 160-fold increase in substrate affinity, a 326-fold enhancement in catalytic efficiency against glyphosate, with little difference between their pH and temperature stabilities. The role of these mutations was explored through structure modeling and molecular docking, revealing that the Arg(51 mutation is near the active site and could be an important residue contributing to the stabilization of glyphosate binding, while the role of the remaining mutations is unclear. These results provide insight into the application of directed evolution in optimizing glycine oxidase function and have laid a foundation for the development of glyphosate-tolerant crops.

Assessment of Paclobutrazol’s Time and Concentration of Foliar Application on Production and Germination of Potato (Solanum tuberosum L. Mini-tube

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B Saadatian

2018-02-01

Full Text Available Introduction Health and quality of potato (Solanum tuberosum L. seeds are important in the potato seed production technology. Moreover, the basic seed materials must be free of pathogens. Therefore tissue culture techniques are used at this stage in the laboratory to produce disease free seeds. Mini-tubers can be produced after acclimatization from plantlets as tissue culture which are planted at high densities in the greenhouse in beds or containers using different substrate mixtures, or even in hydroponic culture. Foliar application of growth regulators is a way to increase potato mini-tuber production. Growth regulators influence on potato mini-tuber dormancy. Triazoles, a family which Paclobutrazol belongs to them, have both fungitoxic and plant growth regulatory effects. In addition, they can also protect plants against various stresses. Therefore, the triazoles have been characterized as plant multi-protestants. Paclobutrazol changes the relationship between source and sink and by this way, affects plant production. Also, it can inhibit giberellic acid biosynthesis. Some morphological changes observed in paclobutrazol-treated plants include the inhibition of plant growth, decreased inter-nodal elongation and increased root to shoot ratios. Time of paclobutrazol foliar application is an important factor which changes plant characters (Lim et al., 2004. This study implemented to evaluate foliar application of paclobutrazol concentrations at different time on production and mini-tuber dormancy. Materials and Methods The factorial experiment based on randomized complete block design with four replications was conducted at the faculty of agriculture’s research greenhouse, Ferdowsi University of Mashhad, Iran, in 2013. Plantlets of Agria cv. produced from nodal tissue culture in Murashinge and Skoog (MS medium. After 25 days, plantlets of free disease and uniform exported to plastic pots with 12 cm diameter and 30 cm height. Perlite, cocopite

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

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Yang, Xiaomei; Wang, Fei; Bento, Célia P M; Xue, Sha; Gai, Lingtong; van Dam, Ruud; Mol, Hans; Ritsema, Coen J; Geissen, Violette

2015-04-15

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 acid (AMPA) related to soil erosion at two slope gradients (10 and 20°), two rates of pesticide with a formulation of glyphosate (Roundup®) application (360 and 720 mg m(-2)), and a rain intensity of 1.0 mm min(-1) for 1 h on bare soil in hydraulic flumes. Runoff and erosion rate were significantly different within slope gradients (psoil at the end of the experiment decreased significantly with depth (psoil layers, respectively. The risk of contamination in deep soil and the groundwater was thus low, but 5% of the initial application did reach the 2-10 cm soil layer. The risk of contamination of surface water through runoff and sedimentation, however, can be considerable, especially in regions where rain-induced soil erosion is common. Copyright © 2015 Elsevier B.V. All rights reserved.

Influence of foliar applications of humic acids on yield and fruit quality of table grape cv. Italia

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Giuseppe Ferrara

2008-06-01

Significance and impact of study: This study gives new information about the positive effects of foliar application of humic acids, active components of soil and compost organic matter, on yield and fruit quality of table grape. In organic viticulture humic acids may find a valid and appropriate application for a technical and economical use.

Glyphosate and AMPA, "pseudo-persistent" pollutants under real-world agricultural management practices in the Mesopotamic Pampas agroecosystem, Argentina.

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Primost, Jezabel E; Marino, Damián J G; Aparicio, Virginia C; Costa, José Luis; Carriquiriborde, Pedro

2017-10-01

In the Pampas, public concern has strongly risen because of the intensive use of glyphosate for weed control and fallow associated with biotech crops. The present study was aimed to evaluate the occurrence and concentration of the herbicide and its main metabolite (AMPA) in soil and other environmental compartments of the mentioned agroecosystem, including groundwater, in relation to real-world agricultural management practices in the region. Occurrence was almost ubiquitous in solid matrices (83-100%) with maximum concentrations among the higher reported in the world (soil: 8105 and 38939; sediment: 3294 and 7219; suspended particulate matter (SPM): 584 and 475 μg/kg of glyphosate and AMPA). Lower detection frequency was observed in surface water (27-55%) with maximum concentrations in whole water of 1.80 and 1.90 μg/L of glyphosate and AMPA, indicating that SPM analysis would be more sensitive for detection in the aquatic ecosystem. No detectable concentrations of glyphosate or AMPA were observed in groundwater. Glyphosate soil concentrations were better correlated with the total cumulative dose and total number of applications than the last spraying event dose, and an increment of 1 mg glyphosate/kg soil every 5 spraying events was estimated. Findings allow to infer that, under current practices, application rates are higher than dissipation rates. Hence, glyphosate and AMPA should be considered "pseudo-persistent" pollutants and a revisions of management procedures, monitoring programs, and ecological risk for soil and sediments should be also recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

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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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Glyphosate rodent carcinogenicity bioassay expert panel review.

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Williams, Gary M; Berry, Colin; Burns, Michele; de Camargo, Joao Lauro Viana; Greim, Helmut

2016-09-01

Glyphosate has been rigorously and extensively tested for carcinogenicity by administration to mice (five studies) and to rats (nine studies). Most authorities have concluded that the evidence does not indicate a cancer risk to humans. The International Agency for Research on Cancer (IARC), however, evaluated some of the available data and concluded that glyphosate probably is carcinogenic to humans. The expert panel convened by Intertek assessed the findings used by IARC, as well as the full body of evidence and found the following: (1) the renal neoplastic effects in males of one mouse study are not associated with glyphosate exposure, because they lack statistical significance, strength, consistency, specificity, lack a dose-response pattern, plausibility, and coherence; (2) the strength of association of liver hemangiosarcomas in a different mouse study is absent, lacking consistency, and a dose-response effect and having in high dose males only a significant incidence increase which is within the historical control range; (3) pancreatic islet-cell adenomas (non-significant incidence increase), in two studies of male SD rats did not progress to carcinomas and lacked a dose-response pattern (the highest incidence is in the low dose followed by the high dose); (4) in one of two studies, a non-significant positive trend in the incidence of hepatocellular adenomas in male rats did not lead to progression to carcinomas; (5) in one of two studies, the non-significant positive trend in the incidence of thyroid C-cell adenomas in female rats was not present and there was no progression of adenomas to carcinomas at the end of the study. Application of criteria for causality considerations to the above mentioned tumor types and given the overall weight-of-evidence (WoE), the expert panel concluded that glyphosate is not a carcinogen in laboratory animals.

The effect of soil and foliar applications of magnesium fertilisers on yields and quality of vine (Vitis vinifera, L. grapes

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Andrea Zatloukalová

2011-01-01

Full Text Available A one-year field trial was established with the vine variety Ryzlink vlašský (Riesling italico to evaluate the effect of spring soil applications and 5x repeated foliar application of magnesium fertilisers on yields and quality of grapes. On light soil of the experimental locality Žabčice (ca 25 km south of Brno visual symptoms of Mg deficiency on vine leaves had been monitored in the past. The experiment involved 4 treatments: 1 unfertilised control; 2 spring soil application of Kieserite – 20 kg Mg.ha−1; 3 5x foliar application of a 5% solution of Epso Combitop – Mg, S, Mn, Zn; 11.8 kg Mg.ha−1; 4 5x foliar applications of a 5% solution of Epso Top – Mg, S; 14.8 kg Mg.ha−1.No significant differences among the treatments were detected in the contents of K (1.40–1.67% and Ca (1.63–1.91% in leaves sampled after the applications. After foliar applications the contents of Mg and S significantly increased in treatments 3–4 to 0.42–0.49% and 0.34–0.40 %, respectively compared to treatments 1–2 (0.29–0.30% and 0.22%, respectively. The content of Zn (173–380 mg.kg−1 and Mn (90–551 mg.kg−1 increased significantly in treatment 3 compared to the other treatments. The chlorophyll index did not differ among the treatments. Grape yields (t.ha−1 in treatments 1–4 were the following: 7.04–8.16–7.51–7.26 t.ha−1, respectively. Only the soil-applied treatment 2 differed significantly from the other treatments. The content of sugar (16.5–17.9 °NM, titratable acids (12.78–13.25 g.l−1 and the pH of must (3.02–3.11 did not differ among the treatments.

Facilitated transport of diuron and glyphosate in high copper vineyard soils.

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Dousset, Sylvie; Jacobson, Astrid R; Dessogne, Jean-Baptiste; Guichard, Nathalie; Baveye, Philippe C; Andreux, Francis

2007-12-01

The fate of organic herbicides applied to agricultural fields may be affected by other soil amendments, such as copper applied as a fungicide. The effect of copper on the leaching of diuron and glyphosate through a granitic and a calcareous soil was studied in the laboratory using sieved-soil columns. Each soil was enriched with copper sulfate to obtain soil copper concentrations of 125, 250, 500, and 1000 mg kg(-1). Glyphosate leaching was influenced by soil pH and copper concentration, whereas diuron leaching was not. In the calcareous soil, glyphosate leaching decreased as copper levels increased from 17 mg kg(-1) (background) to 500 mg kg(-1). In the granitic soil, glyphosate leaching increased as copper levels increased from 34 mg kg(-1) (background) to 500 mg kg(-1). The shapes of the copper elution curves in presence of glyphosate were similar to shapes of the glyphosate curves, suggesting the formation of Cu-glyphosate complexes that leach through the soil. Soil copper concentration does not influence diuron leaching. In contrast, increasing copper concentrations reduces glyphosate leaching through calcareous soils, and conversely, increases glyphosate leaching through granitic soils. Our findings suggest that the risk of groundwater contamination by glyphosate increases in granitic soils with elevated copper concentrations.

Pattern of zinc-65 incorporation into soybean seeds by root absorption, stem injection, and foliar application

International Nuclear Information System (INIS)

Khan, A.; Weaver, C.M.

1989-01-01

The pattern of 65 Zn incorporation into soybean seeds of plants grown hydroponically and intrinsically labeled with 65 Zn by root absorption, stem injection, and foliar application was studied. Stem injection resulted in the greatest (64.5% of dose) accumulation of 65 Zn while incorporation of 65 Zn through root absorption was the least (23.4%) and through foliar application was intermediate (37.5%). Regardless of the labeling techniques, approximately 40-45% of the seed 65 Zn was associated with the subcellular organelles. The pattern of zinc incorporation did not change appreciably as a result of the labeling technique. The major portion of the soluble zinc was not associated with the major proteins (11S and 7S) of soybeans but either was free or was associated with very low molecular weight amino acids, peptides, or their complexes with phytic acid. Zinc in soybean seems to be ionically bound, and this association is affected by the pH of the extracting buffer

Foliar potassium nitrate application improves the tolerance of Citrus macrophylla L. seedlings to drought conditions.

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Gimeno, V; Díaz-López, L; Simón-Grao, S; Martínez, V; Martínez-Nicolás, J J; García-Sánchez, F

2014-10-01

Scarcity of water is a severe limitation in citrus tree productivity. There are few studies that consider how to manage nitrogen (N) nutrition in crops suffering water deficit. A pot experiment under controlled-environment chambers was conducted to explore if additional N supply via foliar application could improve the drought tolerance of Citrus macrophylla L. seedlings under dry conditions. Two-month-old seedlings were subjected to a completely random design with two water treatments (drought stress and 100% water/field capacity). Plants under drought stress (DS) received three different N supplies via foliar application (DS: 0, DS + NH4NO3: 2% NH4NO3, DS + KNO3: 2% KNO3). KNO3-spraying increased leaf and stem DW as compared with DS + NH4NO3 and DS treatments. Leaf water potential (Ψw) was decreased by drought stress in all the treatments. However, in plants from DS + NH4NO and DS + KNO3, this was due to a decrease in the leaf osmotic potential, whereas the decrease in those from the DS treatment was due to a decrease in the leaf turgor potential. These responses were correlated with the leaf proline and K concentrations. DS + KNO3-treated plants had a higher leaf proline and K concentration than DS-treated plants. In terms of leaf gas exchange parameters, it was observed that net assimilation of CO2 [Formula: see text] was decreased by drought stress, but this reduction was much lower in DS + KNO3-treated plants. Thus, when all results are taken into account, it can be concluded that a 2% foliar-KNO3 application can enhance the tolerance of citrus plants to water stress by increasing the osmotic adjustment process. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Degradation of 14C-glyphosate in compost amended soils.

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Alexa, E; Bragea, M; Sumalan, R; Negrea, M; Lazureanu, A

2009-01-01

Glyphosate (N-phosphonomethyl-glycine), the active ingredient in several herbicide formulations, is a non-selective, post-emergent herbicide used in a variety of crop and non-crop situations. Glyphosate is a non-volatile herbicide that is relatively immobile in soil. Its degradation is due to microbiological processes and most laboratory studies have been conducted with 14C-glyphosate with the rate of 14CO2 evolution being used as an indication of herbicide breakdown. In this paper we have studied the glyphosate degradation in compost amendment soils using Scientilator Liquid TRIATHLER and Glyphosate-phosphonomethyl-14C-labeled with specific activity 2,2mCi/mmol. Four types of soils have been taken under study: Black Chernozem, Vertisol, Gleysol and Phaeozem with different characteristics. For the each type of soil have been realized four experimental variants (glyphosate blind sample with 1,5 ppm, concentration, autoclaved soil, soil with glyphosate and addition of compost in field concentration of 40 t/ha, respectively 60 t/ha. The mineralization curves of 14CO2 accumulated were compared during of 40 days. All the mineralization curves for the soils exhibited same patterns, with only two phases, the initial rapid phase of degradation, for about 20 days, attributed to microbial action on the free glyphosate and the second slow phase, when the curves attained plateaus. Compost applied with different concentrations to Vertisol and Black Chernozem did not appear to stimulate the microbial degradation of glyphosate. In Gleysol and Phaeozem with lower humus content, the mineralization curve of 14C indicate the increase degradation capacity, expressed as accumulated 14CO2 as % total 14C, with the increase of compost concentration.

Foliar application of ascorbic acid mitigates sodium chloride induced stress in eggplant (solanum melongena l.)

International Nuclear Information System (INIS)

Jan, S.; Hamayun, M.

2016-01-01

The current work was designed to test the effect of sodium chloride on germination, seedling establishment, vegetative growth, yield, chemical contents and ionic composition of eggplant. The consequences of foliar application of ascorbic acid (AA) on mitigation of adverse effects of sodium chloride were also tested. The seeds of Solanum melongena were germinated using NaCl (60 mM, 100 mM) and ascorbic acid (100 and 200 mM). High levels of salinity significantly affected the seed germination and seedling fresh and dry weights. Plants grown under salinity stress with foliar application of ascorbic acid showed significant increase in germination percentage and seedlings growth as compare to control plants. Sodium chloride stress showed adverse effects on plant height, root length, number of leaves, leaf area, fresh and dry biomass, total chlorophyll, carbohydrates and proteins as compared to untreated plants. The relative water content, electrolyte leakage were increased and Na+ and K+ ions balance was disturbed in different plant parts. Ascorbic acid (100 and 200ppm) enhanced all the growth parameters affected adversely by sodium chloride stress. (author)

Estabelecimento de condições operacionais para o bico rotativo micromax na aplicação do herbicida glyphosate Establishment of operational conditions for micromax rotary atomizers in the application of glyphosate

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P. C. R. Oliveira

1984-01-01

Full Text Available Alguns parâmetros operaciona is do bico rotativo Micromax para apli cação do herbi cida glypho sate foram estudados em condições de laboratório. O bico Micromax a 1.600 rpm e vazão de 0,96 //min forneceu gotas com vmd de 280 μm e à vazão de 0,43 i/min , de 232 μm, sendo que em ambas as condições o coeficient e de dispersão (r = vmd/nmd foi inferior a 1,4, atendendo, portanto, às especificações para o processo CDA. A distância entre bicos a serem montadas numa barra foi determinada em mesa de estudo do padrão de deposição foi de 1,80 m para a vazão de 0,96 Z/min e concentração da formulação comercial do glyphosate entre 4% e 6%. Essa distancia foi de 1,40 m para vazão de 0,43 1/min e concentração de glyphosate entre 9% e 13%. Distancias fora dessas especificações produziram deposições bastante irregulares sob a barra de pulverização.Some operation al parameters of Micromax rotary atomizers in the application of glyphosate were studied under laboratory conditions. Micromax nozzle at 1.600 rpm and 0,96 1/min feed rate produced 280m vmd droplets and 0,43 1/min feed rate, produ ced 232 m vmd droplets. In both conditions the dispersion coefficien t (r = vmd/nmd was bellow 1,4, attending to the spedfication for CDA. Nozzl espacement between Micromax heads in a spray boom was estab lished as 1,80 m for 0,96 1/min feed rate using 4% to 6% glyphosate (commercia l solution and 1,40 m for 0,43 Z/min feed rate using 9% to 13% solution. Nozzle spacement out of these specifications produces very irregular deposition patterns.

A glyphosate-based pesticide impinges on transcription

International Nuclear Information System (INIS)

Marc, Julie; Le Breton, Magali; Cormier, Patrick; Morales, Julia; Belle, Robert; Mulner-Lorillon, Odile

2005-01-01

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

THE REMOVAL OF GLYPHOSATE FROM DRINKING WATER

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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...

Removal of glyphosate herbicide from water using biopolymer membranes.

Science.gov (United States)

Carneiro, Rafael T A; Taketa, Thiago B; Gomes Neto, Reginaldo J; Oliveira, Jhones L; Campos, Estefânia V R; de Moraes, Mariana A; da Silva, Camila M G; Beppu, Marisa M; Fraceto, Leonardo F

2015-03-15

Enormous amounts of pesticides are manufactured and used worldwide, some of which reach soils and aquatic systems. Glyphosate is a non-selective herbicide that is effective against all types of weeds and has been used for many years. It can therefore be found as a contaminant in water, and procedures are required for its removal. This work investigates the use of biopolymeric membranes prepared with chitosan (CS), alginate (AG), and a chitosan/alginate combination (CS/AG) for the adsorption of glyphosate present in water samples. The adsorption of glyphosate by the different membranes was investigated using the pseudo-first order and pseudo-second order kinetic models, as well as the Langmuir and Freundlich isotherm models. The membranes were characterized regarding membrane solubility, swelling, mechanical, chemical and morphological properties. The results of kinetics experiments showed that adsorption equilibrium was reached within 4 h and that the CS membrane presented the best adsorption (10.88 mg of glyphosate/g of membrane), followed by the CS/AG bilayer (8.70 mg of glyphosate/g of membrane). The AG membrane did not show any adsorption capacity for this herbicide. The pseudo-second order model provided good fits to the glyphosate adsorption data on CS and CS/AG membranes, with high correlation coefficient values. Glyphosate adsorption by the membranes could be fitted by the Freundlich isotherm model. There was a high affinity between glyphosate and the CS membrane and moderate affinity in the case of the CS/AG membrane. Physico-chemical characterization of the membranes showed low values of solubility in water, indicating that the membranes are stable and not soluble in water. The SEM and AFM analysis showed evidence of the presence of glyphosate on CS membranes and on chitosan face on CS/AG membranes. The results showed that the glyphosate herbicide can be adsorbed by chitosan membranes and the proposed membrane-based methodology was successfully used to

Levels of glyphosate in surface waters, sediments and soils associated with direct sowing soybean cultivation in north pampasic region of Argentina

Energy Technology Data Exchange (ETDEWEB)

Peruzzo, Pablo J. [Grupo Materiales Polimericos, INIFTA - Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas (UNLP-CONICET), Diag. 113 y 64, CC 16 Suc 4, 1900 La Plata (Argentina); Porta, Atilio A. [CIMA - Centro de Investigaciones del Medio Ambiente, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata (Argentina); Division Quimica Analitica, Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata (Argentina)], E-mail: aporta@quimica.unlp.edu.ar; Ronco, Alicia E. [CIMA - Centro de Investigaciones del Medio Ambiente, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata (Argentina)

2008-11-15

Levels of glyphosate were determined in water, soil and sediment samples from a transgenic soybean cultivation area located near to tributaries streams of the Pergamino-Arrecifes system in the north of the Province of Buenos Aires, Argentina. Field work took into account both the pesticide application and the rains occurring after applications. The pesticide was analysed by HPLC-UV detection, previous derivatization with 9-fluorenylmethylchloroformate (FMOC-Cl). In addition, SoilFug multimedia model was used to analyse the environmental distribution of the pesticides. In the field, levels of glyphosate in waters ranged from 0.10 to 0.70 mg/L, while in sediments and soils values were between 0.5 and 5.0 mg/Kg. Temporal variation of glyphosate levels depended directly on the time of application and the rain events. The results obtained from the application of the model are in accordance with the values found in the field. - Glyphosate concentrations in the environment from a region where little information exists about this and intensive cultivation activities predominate in large areas.

Levels of glyphosate in surface waters, sediments and soils associated with direct sowing soybean cultivation in north pampasic region of Argentina

International Nuclear Information System (INIS)

Peruzzo, Pablo J.; Porta, Atilio A.; Ronco, Alicia E.

2008-01-01

Levels of glyphosate were determined in water, soil and sediment samples from a transgenic soybean cultivation area located near to tributaries streams of the Pergamino-Arrecifes system in the north of the Province of Buenos Aires, Argentina. Field work took into account both the pesticide application and the rains occurring after applications. The pesticide was analysed by HPLC-UV detection, previous derivatization with 9-fluorenylmethylchloroformate (FMOC-Cl). In addition, SoilFug multimedia model was used to analyse the environmental distribution of the pesticides. In the field, levels of glyphosate in waters ranged from 0.10 to 0.70 mg/L, while in sediments and soils values were between 0.5 and 5.0 mg/Kg. Temporal variation of glyphosate levels depended directly on the time of application and the rain events. The results obtained from the application of the model are in accordance with the values found in the field. - Glyphosate concentrations in the environment from a region where little information exists about this and intensive cultivation activities predominate in large areas

Sorption and desorption of glyphosate, MCPA and tetracycline and their mixtures in soil as influenced by phosphate.

Science.gov (United States)

Munira, Sirajum; Farenhorst, Annemieke

2017-12-02

Phosphate fertilizers and herbicides such as glyphosate and MCPA are commonly applied to agricultural land, and antibiotics such as tetracycline have been detected in soils following the application of livestock manures and biosolids to agricultural land. Utilizing a range of batch equilibrium experiments, this research examined the competitive sorption interactions of these chemicals in soil. Soil samples (0-15 cm) collected from long-term experimental plots contained Olsen P concentrations in the typical (13 to 20 mg kg -1 ) and elevated (81 to 99 mg kg -1 ) range of build-up phosphate in agricultural soils. The elevated Olsen P concentrations in field soils significantly reduced glyphosate sorption up to 50%, but had no significant impact on MCPA and tetracycline sorption. Fresh phosphate additions in the laboratory, introduced to soil prior to, or at the same time with the other chemical applications, had a greater impact on reducing glyphosate sorption (up to 45%) than on reducing tetracycline (up to 13%) and MCPA (up to 8%) sorption. The impact of fresh phosphate additions on the desorption of these three chemicals was also statistically significant, but numerically very small namely glyphosate and tetracycline and 3% for MCPA. The presence of MCPA significantly reduced sorption and increased desorption of glyphosate, but only when MCPA was present at concentrations much greater than environmentally relevant and there was no phosphate added to the MCPA solution. Tetracycline addition had no significant effect on glyphosate sorption and desorption in soil. For the four chemicals studied, we conclude that when mixtures of phosphate, herbicides and antibiotics are present in soil, the greatest influence of their competitive interactions is phosphate decreasing glyphosate sorption and the presence of phosphate in solution lessens the potential impact of MCPA on glyphosate sorption. The presence of chemical mixtures in soil solution has an overall greater impact

Effects of additives on glyphosate activity in purple nutsedge

International Nuclear Information System (INIS)

Rungsit Suwanketnikom

1998-01-01

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 (NH 4 ) 2 SO 4 at 1.0% (v/v) + diesel oil at 1,0% (v/v) + Tendal at 1.0% (v/v) increased 14 C-glyphosate penetration into nutsedge leaves more than the addition of either one alone. (NH 4 ) 2 SO 4 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)

Epidemiologic studies of glyphosate and cancer: a review.

Science.gov (United States)

Mink, Pamela J; Mandel, Jack S; Sceurman, Bonnielin K; Lundin, Jessica I

2012-08-01

The United States Environmental Protection Agency and other regulatory agencies around the world have registered glyphosate as a broad-spectrum herbicide for use on multiple food and non-food use crops. Glyphosate is widely considered by regulatory authorities and scientific bodies to have no carcinogenic potential, based primarily on results of carcinogenicity studies of rats and mice. To examine potential cancer risks in humans, we reviewed the epidemiologic literature to evaluate whether exposure to glyphosate is associated causally with cancer risk in humans. We also reviewed relevant methodological and biomonitoring studies of glyphosate. Seven cohort studies and fourteen case-control studies examined the association between glyphosate and one or more cancer outcomes. Our review found no consistent pattern of positive associations indicating a causal relationship between total cancer (in adults or children) or any site-specific cancer and exposure to glyphosate. Data from biomonitoring studies underscore the importance of exposure assessment in epidemiologic studies, and indicate that studies should incorporate not only duration and frequency of pesticide use, but also type of pesticide formulation. Because generic exposure assessments likely lead to exposure misclassification, it is recommended that exposure algorithms be validated with biomonitoring data. Copyright © 2012 Elsevier Inc. All rights reserved.

Foliar applications of iron promote flavonoids accumulation in grape berry of Vitis vinifera cv. Merlot grown in the iron deficiency soil.

Science.gov (United States)

Shi, Pengbao; Song, Changzheng; Chen, Haiju; Duan, Bingbing; Zhang, Zhenwen; Meng, Jiangfei

2018-07-01

Flavonoids are important compounds for grape and wine quality. Foliar fertilization with iron compounds has been reported to have a substantial impact on grape composition in the grapevines growing in calcareous soil. However, much less is known about its real impact on flavonoid composition. In the present study, Ferric ethylenediamine di (O-hydroxyphenylacetic) acid (Fe-EDDHA) was foliar applied to Merlot (Vitis vinifera L.) grapevines growing in calcareous soil over two consecutive vintages in order to study its effect on grape flavonoid composition. Fe-EDDHA foliar supply tended to increase grape sugar, anthocyanin and flavonol content, decrease acid content and enhance the juice pH when compared to the control. Principal component analysis showed that the vintage also had influence on grape quality. The results suggested that Fe-EDDHA foliar application had an enhancement effect on grape secondary metabolism, and the effect increased the nutritional value of the consequent grapes and wines. Copyright © 2018 Elsevier Ltd. All rights reserved.

Soil Properties Control Glyphosate Sorption in Soils Amended with Birch Wood Biochar

DEFF Research Database (Denmark)

Kahawaththa Gamage, Inoka Damayanthi Kumari; Moldrup, Per; Paradelo, Marcos

2016-01-01

Abstract Despite a contemporary interest in biochar application to agricultural fields to improve soil quality and long-term carbon sequestration, a number of potential side effects of biochar incorporation in field soils remain poorly understood, e.g., in relation to interactions...... with agrochemicals such as pesticides. In a fieldbased study at two experimental sites in Denmark (sandy loam soils at Risoe and Kalundborg), we investigated the influence of birch wood biochar with respect to application rate, aging (7–19 months), and physico- chemical soil properties on the sorption coefficient......, Kd (L kg−1), of the herbicide glyphosate. We measured Kd in equilibrium batch sorption experiments with triplicate soil samples from 20 field plots that received biochar at different application rates (0 to 100 Mg ha−1). The results showed that pure biochar had a lower glyphosate Kd value as compared...

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.

Effect of 2,4-D and atrazine when applied with glyphosate ripener

Science.gov (United States)

Management of late-season morningglory infestations in sugarcane is accomplished with aerial applications of the postemergence herbicides 2,4-D, dicamba, or atrazine. Likewise, the aerial application of glyphosate prior to harvest to improve stalk sucrose levels is a common practice for many Louisia...

Foliar urea application affects nitric oxide burst and glycine betaine metabolism in two maize cultivars under drought

International Nuclear Information System (INIS)

Zhang, L.; Zhang, X.; Wang, K.; Zhao, Y.; Zhai, Y.; Gao, M.

2011-01-01

Foliar urea has been proved to act a better role in alleviation of the negative effects of drought stress (DS). However, the modulation mechanism of foliar urea are not conclusive in view of nitric oxide (NO) burst and glycine betaine metabolism and their relationship. Two maize ( Zea mays L.) cultivars (Zhengdan 958, JD958, Jundan 20, ZD20) were grown in hydroponic medium, which were treated with spraying of urea concentration of 15 g L/sup -1/ and two water regimes (non-stress and DS simulated by the addition of polyethylene glycol (PEG, 15% w/v, MW 6000). The ten-day DS treatment increased betaine aldehyde dehydrogenase (BADH) activity, choline content and nitric oxide (NO) content acted as the key enzyme, initial substrate and a nitrogenous signal substance respectively in GB synthesis metabolism, thus, induced to great GB accumulation. The accumulation of NO reached the summit earlier than that of GB. The more positive/less negative responses were recorded in JD958 as compared with ZD20 to DS. Addition of foliar ur ea could increase accumulation of choline and BADH activity as well as NO content, thereby, increase GB accumulation under DS. These positive effects of urea applying foliarly on all parameters measured were more pronounced in cultivar JD20 than those in ZD958 under drought. It is, therefore, concluded that increases of both BADH activity and choline content possibly resulted in enhancement of GB accumulation. Foliar urea application could provoke better GB accumulation by modulation of GB metabolism, possibly mediating by NO burst as a signal molecule during drought, especially in the drought sensitive maize cultivar. (author)

Glyphosate sorption/desorption on biochars - interactions of physical and chemical processes.

Science.gov (United States)

Hall, Kathleen E; Spokas, Kurt A; Gamiz, Beatriz; Cox, Lucia; Papiernik, Sharon K; Koskinen, William C

2018-05-01

Biochar, a carbon-rich product of biomass pyrolysis, could limit glyphosate transport in soil and remediate contaminated water. The present study investigates the sorption/desorption behavior of glyphosate on biochars prepared from different hardwoods at temperatures ranging from 350 to 900 °C to elucidate fundamental mechanisms. Glyphosate (1 mg L -1 ) sorption on biochars increased with pyrolysis temperature and was highest on 900 °C biochars; however, total sorption was low on a mass basis (glyphosate in soils, did not alter biochar sorption capacities. Glyphosate did not desorb from biochar with CaCl 2 solution; however, up to 86% of the bound glyphosate was released with a K 2 HPO 4 solution. Results from this study suggest a combined impact of surface chemistry and physical constraints on glyphosate sorption/desorption on biochar. Based on the observed phosphate-induced desorption of glyphosate, the addition of P-fertilizer to biochar-amended soils can remobilize the herbicide and damage non-target plants; therefore, improved understanding of this risk is necessary. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Response of Some Bread Wheat Cultivars to Foliar Application of Zn and Fe Different Forms in Two Locations with Different Soil Properties

Directory of Open Access Journals (Sweden)

E Arazmjoo

2018-05-01

Full Text Available Introduction Zinc (Zn and iron (Fe are essential mineral nutrients for plant and human growth, and dietary Zn and Fe deficiencies are a worldwide nutritional problem. The Recommended Dietary Allowance (RDA of Zn and Fe are 15 mg and 10 mg per day for human, respectively. However, micronutrient deficiencies affect more than half of the world’s population, especially women and preschool children. Iron is one of the most important micronutrients, and approximately two billion people suffer from iron deficiency worldwide. Zinc deficiency is also considered to be quite common and affects newborn, children, pregnant women and elderly. Micronutrient malnutrition in human in developing countries is derived from deficiencies of these elements in staple food. It is believed that increasing the micronutrient concentrations in these crops could increase the dietary intake of these elements in these regions significantly. More than 80% of arable soils in Iran are zinc-deficient with an average yield depression of around 50%. It is, therefore, highly important to develop cost-effective and quick solutions to the Zn and Fe deficiency problem. Materials and Methods In order to evaluate the effect of foliar application of zinc and iron different forms on yield components, phonological and morphological traits and grain yield of some wheat cultivars in two locations with different physico-chemical soil properties, two experiments in factorial arranged in randomized complete block design with three replications conducted during 2015-16 cropping season. Experimental treatments were included: wheat cultivars Roshan, Roshan Back cross (old cultivars, Bam and Ofogh (new cultivars, zinc application in three levels of foliar application of water (control, zinc sulfate and chelated zinc and iron application in three levels of foliar application of water (control, iron sulfate and chelated iron (equivalent to 2.5 kg ha-1. The first experiment was conducted at the

Subtle impacts of repeated glyphosate use on wheat-associated bacteria are small and depend on glyphosate use history

Science.gov (United States)

Glyphosate (Roundup) is the most widely used herbicide in the world and a critical tool for weed control in no-till wheat cropping systems. However, there are persistent concerns about non-target impacts of long-term glyphosate use on soil communities. We investigated the impacts of repeated glyphos...

Natural glyphosate tolerance in sweetvetch Hedysarum boreale

Science.gov (United States)

Sweetvetch (Hedysarum boreale Nutt.) a legume native to the western USA and Canada, is purported to have tolerance to glyphosate {N-(phosphonomethyl) glycine} herbide. Eight rates of glyphosate were tested for their effect on biomass yield (BMY) and survival of seedlings and mature plants. Treatme...

Glyphosate tolerance of soybean mutant gained after boarding on satellite

International Nuclear Information System (INIS)

Jiang Lingxue; Ren Honglei; Zhang Hongyan; Liu Zhangxiong; Jin Longguo; Guo Yong; Qiu Lijuan; Tao Bo

2011-01-01

Glyphosate-tolerant germplasm and genetic variation characteristics of SP 2 and SP 3 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 SP 3 of Zhongpin, and one glyphosate-resistance variant was screened from Zhongpin 661 SP 3 . 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)

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. Copyright © 2011 Society of Chemical Industry.

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

Glyphosate Dissipation in Different Soils Under No-Till and Conventional Till

Science.gov (United States)

Okada, Elena; Costa, Jose Luis; Francisco, Bedmar

2017-04-01

Glyphosate is the most used herbicide in Argentina, accounting for 62% of the commercialized pesticides in the market. It is used as a weed controller in chemical fallow under no-till systems, and it is also applied in various genetically modified crops (e.g. soybean, corn, cotton). Though it has a high solubility in water, it tends to adsorb and accumulate in agricultural soils. The description of glyphosate biodegradation in soils with a long term history under agricultural practices is of interest. The main objectives of this work were to compare the dissipation of glyphosate and the accumulation of its metabolite aminomethylphosphonic acid (AMPA) over time in three soils from Argentina. The studied soils belong to areas of high agronomic land use and different edaphoclimatic conditions, situated in Manfredi (MAN), Pergamino (PER) and Paraná (PAR). Soil samples were taken from long-term field trials with a history of more than 16 years under no-till and conventional tillage management. To study glyphosate dissipation in soil under controlled laboratory conditions, 400 g of dry soil sample were placed in 1.5 L flasks. A dose corresponding to 6 L ha-1 of commercial glyphosate ATANOR II® (35.6 % a.i.) was applied on day 0. The dose applied was equivalent to a final concentration in soil of 4000 μg Kg-1 of active ingredient. The moisture of the soil samples was kept at 60 % of the field capacity. Samples were incubated in the dark at a constant temperature of 22°C ± 1°C. A sub-sample of 5 g was taken from each flask at day 0 (after application), 1, 3, 7, 15, 20, 28, 44 and 62. Glyphosate and AMPA in soil samples was extracted with a strong basic solution (100 mM Na2B4O7•10H2O/ 100 mM K3PO4, pH=9) and then derivitazed with FMOC-Cl. Detection and quantification of the compounds was performed by ultra-performance liquid chromatography coupled with a mass spectrometer (UPLC MS/MS). The results showed that forty percent of the applied glyphosate was degraded

FOLIAR FERTILIZATION ON PINEAPPLE QUALITY AND YIELD ADUBAÇÃO FOLIAR NA QUALIDADE E PRODUTIVIDADE DE ABACAXI

Directory of Open Access Journals (Sweden)

Marcelo Carvalho Minhoto Teixeira Filho

2011-04-01

Full Text Available There are just a few studies using foliar sprays with micronutrients on pineapple crops. The objective of this study was to evaluate the B and Zn effect, as chelate, acid or salt, via foliar feeding, on fruit yield and quality. The experiment was carried out in Guaraçaí, São Paulo State, Brazil, in a loamy medium texture soil, by using Smooth Cayenne (Hawaiian pineapple seedlings. A randomized block design with four replications was adopted, with 110 g ha-1 of B and 250 g ha-1 of Zn for each application. Two foliar sprays were applied, at 7 and 9 months after planting. The B and Zn sources did not affect the total soluble solids contents, titratable acidity, average fruit diameter, fruit length without crown, and maturity index. Only the B, Zn, and K concentrations in the leaves were influenced by the application of micronutrients.

Poucos são os estudos desenvolvidos com a aplicação via foliar de micronutrientes, na cultura do abacaxi. Este trabalho teve como objetivo avaliar os efeitos de B e Zn, em forma de quelato, ácido ou sal, via foliar, buscando-se obter respostas sobre os efeitos na produtividade e qualidade dos frutos. O experimento foi realizado em Guaraçaí (SP, em solo com textura média. Foram utilizadas mudas tipo filhote, da cultivar Smooth Cayenne (Havaiano. O delineamento experimental adotado foi o de blocos ao acaso, com quatro repetições, utilizando-se fontes para fornecer, em cada aplicação, 110 g ha^-1 de B e 250 g ha^-1 de Zn. Foram realizadas duas pulverizações foliares, aos 7 e 9 meses após o plantio. As fontes de B e Zn não exerceram efeito nos teores de sólidos solúveis totais, acidez titulável, diâmetro médio do fruto, comprimento do fruto sem coroa e índice de maturação. Apenas os teores de B, Zn e K, na

Manejo de Conyza bonariensis resistente ao glyphosate: coberturas de inverno e herbicidas em pré-semeadura da soja Management of glyphosate resistant Conyza bonariensis: winter cover crops and herbicides in soybean pre-seeding

Directory of Open Access Journals (Sweden)

F.P. Lamego

2013-06-01

cover crops lopsided oat, radish, common vetch, Italian ryegrass, wheat, and fallow in the main plots, and in the subplots, the following burn-down treatments: glyphosate (720 g e.a ha-1, glyphosate (720 g e.a ha-1 + 2,4-D (1.050 g e.a ha-1, glyphosate (720 g e.a ha-1 + 2,4-D (1.050 g e.a ha‑1/paraquat (200 g i.a ha-1 + diuron (100 g i.a ha-1, glyphosate (720 g e.a ha-1 + chlorimuron-ethyl (80 g i.a ha-1, glyphosate (720 g e.a ha-1 + chlorimuron-ethyl (80 g i.a ha-1/paraquat (200 g i.a ha-1 + diuron (100 g i.a ha-1 and mowing. Radish was the cover crop species that produced the highest amount of shoot dry mass during the winter season, while common vetch had the highest suppressive effect on germination and initial development of C. bonariensis. Associations of glyphosate with 2,4-D or chlorimuron-ethyl, followed by the sequential application of paraquat + diuron, caused the highest reductions in C. bonariensis infestation.

Determination of glyphosate by high performance liquid ...

African Journals Online (AJOL)

The aim of this study was to design a glyphosate analysis method. This molecule is an organic pollutant from water and soil. We have developed a chromatographic method with phenylisothiocyanate. This molecule has allowed obtaining an intermediate molecule with the glyphosate being easily detectable in ...

150 ACUTE TOXICITY OF GLYPHOSATE ON CLARIAS ...

African Journals Online (AJOL)

The effects of glyphosate on mortality rate and behavioural responses of Clarias gariepinus fingerlings were investigated under laboratory conditions for 96 hours exposure period. The lethal concentration (LC50) value of glyphosate on fingerlings of Clarias gariepinus was 0.0018 ml/l for 96 hours of exposure.

EMERGÊNCIA E ESTABELECIMENTO DE PLANTAS CULTIVADAS APÓS APLICAÇÃO DE GLYPHOSATE

OpenAIRE

BELUCI, Lucas Ribeiro; AZANIA, Carlos Alberto Mathias; VITORINO, Renan; AZANIA, Andrea Padua; GARCIA, Julio César; SILVA, Danilo Manoel da

2014-01-01

The research aimed to study the effect glyphosate doses, used in the sugarcane chemical destruction, on the emergence and early development of soybean, corn and peanut, sown in succession. An experiment was conducted for each crop in pots using a randomized design with treatments arranged in a 2 x 6 factorial and four replications with seeding times (1 and 12 days after application) and glyphosate doses (0, 1440, 2160, 2880, 3600 and 4320 g ha-1). The experimental units consisted of plast...

Iron supply to soybean plants through the foliar application of IDHA/Fe3+: effect of plant nutritional status and adjuvants.

Science.gov (United States)

Rodríguez-Lucena, Patricia; Ropero, Edgar; Hernández-Apaolaza, Lourdes; Lucena, Juan J

2010-12-01

Synthetic Fe chelates are commonly used to overcome Fe deficiencies in crops, but most of them are scarcely biodegradable. Iminodisuccinic acid (IDHA) is a biodegradable chelating agent that is currently being evaluated as an alternative to EDTA. In this work, the efficacy of the foliar application of IDHA/Fe(3+) to soybean chlorotic plants under controlled conditions was studied, testing the influence of the adjuvant used and of the plant nutritional status. When IDHA/Fe(3+) was applied to soybean plants with severe Fe chlorosis and the foliar sprays were the sole source of Fe, this chelate behaved similarly to the EDTA/Fe(3+) and the recovery of the plants was slight in both cases. The same chelates were tested when foliar sprays were an additional source of Fe for mildly chlorotic plants, which were also being supplied with low concentrations of Fe applied to the nutrient solution. Then, plant recovery was appreciable in all cases, and the IDHA/Fe(3+) was as effective as EDTA/Fe(3+). Among the adjuvants studied, a urea-based product was the only one that did not damage the leaf surface and that could improve the efficiency of IDHA/Fe(3+) up tp the level of EDTA/Fe(3+). Thus, it was concluded the foliar application of IDHA/Fe(3+) can be an environmentally friendly alternative to the non-biodegradable chelate EDTA/Fe(3+) when the appropriate adjuvant is used. Copyright © 2010 Society of Chemical Industry.

Spatial glyphosate and AMPA redistribution on the soil surface driven by sediment transport processes - A flume experiment.

Science.gov (United States)

Bento, Célia P M; Commelin, Meindert C; Baartman, Jantiene E M; Yang, Xiaomei; Peters, Piet; Mol, Hans G J; Ritsema, Coen J; Geissen, Violette

2018-03-01

This study investigates the influence of small-scale sediment transport on glyphosate and AMPA redistribution on the soil surface and on their off-site transport during water erosion events. Both a smooth surface (T1) and a surface with "seeding lines on the contour" (T2) were tested in a rainfall simulation experiment using soil flumes (1 × 0.5 m) with a 5% slope. A dose of 178 mg m -2 of a glyphosate-based formulation (CLINIC ® ) was applied on the upper 0.2 m of the flumes. Four 15-min rainfall events (RE) with 30-min interval in between and a total rainfall intensity of 30 mm h -1 were applied. Runoff samples were collected after each RE in a collector at the flume outlet. At the end of the four REs, soil and sediment samples were collected in the application area and in four 20 cm-segments downslope of the application area. Samples were collected according to the following visually distinguished soil surface groups: light sedimentation (LS), dark sedimentation (DS), background and aggregates. Results showed that runoff, suspended sediment and associated glyphosate and AMPA off-site transport were significantly lower in T2 than in T1. Glyphosate and AMPA off-site deposition was higher for T2 than for T1, and their contents on the soil surface decreased with increasing distance from the application area for all soil surface groups and in both treatments. The LS and DS groups presented the highest glyphosate and AMPA contents, but the background group contributed the most to the downslope off-site deposition. Glyphosate and AMPA off-target particle-bound transport was 9.4% (T1) and 17.8% (T2) of the applied amount, while water-dissolved transport was 2.8% (T1) and 0.5% (T2). Particle size and organic matter influenced the mobility of glyphosate and AMPA to off-target areas. These results indicate that the pollution risk of terrestrial and aquatic environments through runoff and deposition can be considerable. Copyright © 2017 Elsevier Ltd

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

International Nuclear Information System (INIS)

Boerboom, C.M.

1989-01-01

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% (I 50 s 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 I 50 s of 0.7 kg/ha glyphosate. The selfed progeny ranged from highly tolerant (I 50 of 1.5 kg/ha) to susceptible (I 50 of 0.5 kg/ha). Spray retention, 14 C-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

Evaluating Maize Yield and the Quality of Response to Vermicompost, in Thiobacillus and Foliar Application of Fe and Zn

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Elnaz Davaran Hagh

2017-08-01

Full Text Available Introduction Half of the world's population suffers from micronutrients malnutrition. Use of bio-fertilizers in sustainable agricultural systems is important in production and enables plants to absorb more water from soil and improves plant nutrient uptake and photosynthesis. Benefits of vermicompost application in agriculture is due to its content of organic matter, plant nutrients and plant growth promotion. Vermicompost increases the absorption and transition of nutrients from soil to roots and improves plant growth (Simsek-Ersahin, 2011. Zn and Fe application is highly important; foliar application causes faster and higher absorption rate and cures deficiencies symptoms (Ghaffari et al., 2010. Thiobacillus is a chemolithotroph bacterium, receiving energy from sulfur oxidation. This bacterium acidifies microcites in the rhizosphere, increasing the availability of nutrients to plant roots (Kaya et al., 2009. Regarding the benefits of integrated nutrient management, this experiment was conducted with the aim of testing the effects of Fe and Zn foliar spraying, Thiobacillu sthiooxidans inoculation and vermicompost application on growth, yield and bio fortification of popcorn maize. Materials and methods This experiment was conducted in 2012 at the research field of Islamic Azad University, Tabriz branch, Iran. The experiment was conducted in factorial in the form of a randomized complete block design with three replications and four factors: vermicompost application in soil (0 and 2 t.ha-1, applied in strip form below the seeds before cultivation, inoculation with Thiobacillus thiooxidans, with a population of 108cfu.g-1. Sulfur was inoculated with T. thiooxidans prior to application. Fe chelate foliar application (without spraying and two times spraying of 0.002 concentration of 13% Fe chelate and Zn chelate foliar application (without spraying and two times spraying of 0.002 concentration of 15% Zn chelate. Maize seeds (Zea mays L. var

The Effects of Foliar Application of Methanol on Morphological Characteristics of Bean (Phaseolus vulgaris L. under Drought Stress Condition

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N. Armand

2016-02-01

Full Text Available Introduction Available water is an important factor for plant growth in arid environments. Results indicated that foliar application of methanol is believed to be more important than the drought tolerance in C3 plant. Since bean is a C3 plant, it performs light respiration under intense heat, light and water stress due to internal leaf CO2 concentration reduction and oxygen concentration increase. Light respiration can cause up to 20% loss of carbon in plants and decrease the yield. Increasing concentration of carbon dioxide can neutralize the effect caused by drought stress. Thus, the use of substances that can cause an increase in the concentration of carbon dioxide in the plant, leads to improving the yield under the drought conditions. One of the ways of increasing the concentration of carbon dioxide in plants is by using compounds such as methanol, ethanol, propanol, butanol as well as use of the amino acids of glycine, glutamate and aspartate. Plants can easily absorb methanol sprayed on leaves and use it as a carbon source added to atmospheric carbon. Methanol is relatively smaller compared to the CO2 molecules, so it can be easily absorbed and utilized by plants. Materials and Methods In order to evaluate the effects of foliar application of methanol on some morphological characteristics of bean under drought stress, a factorial experiment was conducted based on completely randomized block design with three replications in 2014 at the Khatam Alanbia University of Behbahan. The treatment of spraying methanol was at 4 levels include control (without spraying, 10, 20 and 30% v/v methanol which added 2 g l-1 glycine to each of solutions. Adding glycine to aqueous solution of methanol leads to prevention of damages caused by the toxicity of methanol. The drought factors including control (100% field of capacity, moderate drought stress (50% field of capacity and severe drought stress (25% field of capacity were considered. In this experiment

Complementary Evaluation of Iron Deficiency Root Responses to Assess the Effectiveness of Different Iron Foliar Applications for Chlorosis Remediation

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Marta Fuentes

2018-03-01

Full Text Available Iron deficiency in plants is caused by a low availability of iron in the soil, and its main visual symptom is leaf yellowing due to a decrease in chlorophyll content, along with a reduction in plant growth and fruit quality. Foliar sprays with Fe compounds are an economic alternative to the treatment with expensive synthetic Fe-chelates applied to the soil, although the efficacy of foliar treatments is rather limited. Generally, plant response to Fe-foliar treatments is monitored by measuring chlorophyll content (or related parameters as SPAD index. However, different studies have shown that foliar Fe sprays cause a local regreening and that translocation of the applied Fe within the plant is quite low. In this context, the aim of this study was to assess the effects of foliar applications of different Fe compounds [FeSO4, Fe(III-EDTA, and Fe(III-heptagluconate] on Fe-deficient cucumber plants, by studying the main physiological plant root responses to Fe deficiency [root Fe(III chelate reductase (FCR activity; acidification of the nutrient solution; and expression of the Fe deficiency responsive genes encoding FCR, CsFRO1, Fe(II root transporter CsIRT1, and two plasma membrane H+-ATPases, CsHA1 and CsHA2], along with SPAD index, plant growth and Fe content. The results showed that the overall assessment of Fe-deficiency root responses improved the evaluation of the efficacy of the Fe-foliar treatments compared to just monitoring SPAD indexes. Thus, FCR activity and expression of Fe-deficiency response genes, especially CsFRO1 and CsHA1, preceded the trend of SPAD index and acted as indicators of whether the plant was sensing or not metabolically active Fe due to the treatments. Principal component analysis of the data also provided a graphical tool to evaluate the evolution of plant responses to foliar Fe treatments with time.

Effect of glyphosate on wheat quality characteristics

Science.gov (United States)

Glyphosate is the most widely used herbicide in the world. It is a non-selective, broad spectrum, post-emergence herbicide, and therefore controls a wide range of different species. Although glyphosate is effective in weed control, side effects of this herbicide on the crop itself, micro and macro o...

Low doses of glyphosate enhance growth, CO2 assimilation, stomatal conductance and transpiration in sugarcane and eucalyptus.

Science.gov (United States)

Nascentes, Renan F; Carbonari, Caio A; Simões, Plinio S; Brunelli, Marcela C; Velini, Edivaldo D; Duke, Stephen O

2018-05-01

Sublethal doses of herbicides can enhance plant growth and stimulate other process, an effect known as hormesis. The magnitude of hormesis is dependent on the plant species, the herbicide and its dose, plant development stage and environmental parameters. Glyphosate hormesis is well established, but relatively little is known of the mechanism of this phenomenon. The objective of this study was to determine if low doses of glyphosate that cause growth stimulation in sugarcane and eucalyptus concomitantly stimulate CO 2 assimilation. Shoot dry weight in both species increased at both 40 and 60 days after application of 6.2 to 20.2 g a.e. ha -1 glyphosate. The level of enhanced shoot dry weight was 11 to 37%, depending on the time after treatment and the species. Concomitantly, CO 2 assimilation, stomatal conductance and transpiration were increased by glyphosate doses similar to those that caused growth increases. Glyphosate applied at low doses increased the dry weight of sugarcane and eucalyptus plants in all experiments. This hormetic effect was related to low dose effects on CO 2 assimilation rate, stomatal conductance and transpiration rate, indicating that low glyphosate doses enhance photosynthesis of plants. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

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 bioremediation of glyphosate-contaminated soils.

Caracteres anatômicos de duas espécies de trapoeraba e a eficiência do glyphosate Anatomical features of two dayflower species (Commelina spp. on glyphosate efficacy

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I.C. Santos

2002-04-01

Full Text Available O gênero Commelina engloba espécies de plantas daninhas de difícil controle em diversas culturas, principalmente onde o herbicida glyphosate tem sido utilizado com elevada freqüência. Este trabalho foi conduzido com o objetivo de avaliar diferenças entre caracteres anatômicos de Commelina benghalensis e Commelina diffusa, submetidas a crescimento sob condições de sol e sombra, que pudessem influenciar a absorção e translocação deste herbicida. O complexo estomático das duas espécies é semelhante e a folha é anfiestomática. O número de estômatos na epiderme foliar foi maior em C. diffusa (38/mm² em relação a C. benghalensis (33,66/mm², na epiderme abaxial (54,86/mm² em relação à adaxial (16,80/mm² e sob sol (37,89/mm² em relação a sombra (33,77/mm². A epiderme abaxial apresentou maior número de estômatos sob sol. Pêlos secretores, do mesmo tipo, estão presentes nas duas espécies, mas em maior número em C. diffusa. Somente C. benghalensis apresentou pêlos tectores, que são de dois tipos: longos com extremidade afilada e curtos com extremidade curva; os pêlos longos concentram-se na epiderme abaxial e os pêlos curtos, na epiderme adaxial. Apesar de a presença de pêlos na epiderme foliar ser freqüentemente associada à maior absorção de herbicidas, acredita-se que o fator determinante da maior suscetibilidade de C. benghalensis ao glyphosate, em relação a C. diffusa, esteja relacionado à reserva de amido no caule. Enquanto C. benghalensis apresenta poucos e pequenos grãos de amido no parênquima medular, C. diffusa apresenta grandes e numerosos grãos de amido, o que, possivelmente, torna mais lenta a translocação simplástica de herbicidas, reduzindo a quantidade de herbicida acumulada nos pontos de crescimento e permitindo que ela rebrote mesmo após a perda total das folhas.The genus Commelina includes weed species of difficult control in several crops, chiefly when the herbicide glyphosate is

The herbicide Glyphosate affects nitrification in the Elbe estuary, Germany

Science.gov (United States)

Sanders, Tina; Lassen, Stephan

2015-04-01

The Elbe River is one of the biggest European rivers discharging into the North Sea. It also transports high amounts of nutrients and pollutants like pesticides. Important source regions of both nutrients and pollutants are located within the river catchment, which is dominated by agricultural land-use. From these agricultural soils, pesticides can be carried via the river and estuary into the North Sea. Glyphosate (N-(phosphonomethyl) glycine) is the most commonly used herbicide worldwide and mainly used to regulate unwanted plant growth and for the expedition of crop ripening. In Germany, ~ 6000 tons of glyphosate are applied yearly in agriculture and private use. Glyphosate is degradable by microorganisms and has a half-life in water of 35 to 60 days. This herbicide specifically inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), an enzyme that catalyzes the biosynthesis of essential aromatic amino acids in plants, fungi, and bacteria. Nitrifying bacteria, which play an important role in the internal nitrogen cycling in the Elbe estuary, also possess this enzyme. The aim of our study was to quantify the concentration of glyphosate in water and sediment samples of the Elbe to get an overview about relevant environmental levels and to assess the impact of glyphosate on inhibition of nitrifying activities. To quantify the effect of glyphosate on nitrification activity, natural samples as well as pure cultures of Nitrosomonas europea (strain Nm50) were incubated with different concentrations of glyphosate over a period of some weeks. The nitrifying activity was determined according to changes of the nitrite and nitrate concentration as well as the cell number. Glyphosate was detectable in water and sediment samples in the Elbe estuary with up to 5 ppb mainly in the Port of Hamburg region. In both incubation experiments an inhibiting effect of glyphosate on nitrification could be shown. The incubated natural water sample was affected by a glyphosate

Efeitos da dessecação com glyphosate e chlorimuron-ethyl na comunidade infestante e na produtividade da soja Effects of dissection with glyphosate and chlorimuron-ethyl on weed community and soybean yield

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L.B Carvalho

2009-12-01

Full Text Available O efeito de dessecantes sobre o período anterior à interferência (PAI pode auxiliar na tomada de decisão para o manejo das plantas daninhas. O objetivo desta pesquisa foi verificar se a adição de chlorimuron-ethyl ao glyphosate, para dessecação em pré-semeadura, altera a extensão do PAI na soja. O experimento foi realizado em Jaboticabal-SP, Brasil, submetendo-se o cultivar Monsoy 7908RR a oito períodos de convivência com plantas daninhas, além de testemunhas no mato e no limpo, nos quais foram aplicados dois grupos de tratamentos: glyphosate e glyphosate + chlorimuron-ethyl. Em cada período, foram calculados o índice de importância relativa e os índices de diversidade e equitabilidade; por meio da análise de regressão dos dados de produtividade de grãos, determinou-se o PAI. Digitaria insularis, Acanthospermum hispidum, Raphanus raphanistrum e Commelina benghalensis apresentaram maior importância relativa. Os índices de diversidade e equitabilidade oscilaram durante os períodos, e a diferença entre as plantas daninhas fundamentou-se no acúmulo de massa seca. O PAI na soja no tratamento com glyphosate foi de 37 dias após a semeadura (DAS e de 51 DAS naquele com glyphosate + chlorimuron-ethyl. A adição de chlorimuron-ethyl ao glyphosate permite que a cultura conviva mais tempo com as plantas daninhas sem que ocorra redução significativa na produtividade.The effects of burndown herbicides on the period before weed interference (PBI may provide support to weed management decision-making. The objective of this research was to verify whether the PBI is affected by the application of glyphosate plus chlorimuron-ethyl to pre-sowing burndown in soybean. The experiment was carried out in Jaboticabal-SP, Brazil, submitting the cultivar Monsoy 7908RR to eight coexistence periods with weeds, maintaining weedy and-weed-free checks, which were applied to two groups of treatments: glyphosate and glyphosate + chlorimuron-ethyl. At

The Effect of Glyphosate on Human Sperm Motility and Sperm DNA Fragmentation

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George Anifandis

2018-05-01

Full Text Available Glyphosate is the active ingredient of Roundup®, which is one of the most popular herbicides worldwide. Although many studies have focused on the reproductive toxicity of glyphosate or glyphosate-based herbicides, the majority of them have concluded that the effect of the specific herbicide is negligible, while only a few studies indicate the male reproductive toxicity of glyphosate alone. The aim of the present study was to investigate the effect of 0.36 mg/L glyphosate on sperm motility and sperm DNA fragmentation (SDF. Thirty healthy men volunteered to undergo semen analysis for the purpose of the study. Sperm motility was calculated according to WHO 2010 guidelines at collection time (zero time and 1 h post-treatment with glyphosate. Sperm DNA fragmentation was evaluated with Halosperm® G2 kit for both the control and glyphosate-treated sperm samples. Sperm progressive motility of glyphosate-treated samples was significantly reduced after 1 h post-treatment in comparison to the respective controls, in contrast to the SDF of glyphosate-treated samples, which was comparable to the respective controls. Conclusively, under these in vitro conditions, at high concentrations that greatly exceed environmental exposures, glyphosate exerts toxic effects on sperm progressive motility but not on sperm DNA integrity, meaning that the toxic effect is limited only to motility, at least in the first hour.

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...

Evaluation of estrogen receptor alpha activation by glyphosate-based herbicide constituents.

Science.gov (United States)

Mesnage, Robin; Phedonos, Alexia; Biserni, Martina; Arno, Matthew; Balu, Sucharitha; Corton, J Christopher; Ugarte, Ricardo; Antoniou, Michael N

2017-10-01

The safety, including the endocrine disruptive capability, of glyphosate-based herbicides (GBHs) is a matter of intense debate. We evaluated the estrogenic potential of glyphosate, commercial GBHs and polyethoxylated tallowamine adjuvants present as co-formulants in GBHs. Glyphosate (≥10,000 μg/L or 59 μM) promoted proliferation of estrogen-dependent MCF-7 human breast cancer cells. Glyphosate also increased the expression of an estrogen response element-luciferase reporter gene (ERE-luc) in T47D-KBluc cells, which was blocked by the estrogen antagonist ICI 182,780. Commercial GBH formulations or their adjuvants alone did not exhibit estrogenic effects in either assay. Transcriptomics analysis of MCF-7 cells treated with glyphosate revealed changes in gene expression reflective of hormone-induced cell proliferation but did not overlap with an ERα gene expression biomarker. Calculation of glyphosate binding energy to ERα predicts a weak and unstable interaction (-4.10 kcal mol -1 ) compared to estradiol (-25.79 kcal mol -1 ), which suggests that activation of this receptor by glyphosate is via a ligand-independent mechanism. Induction of ERE-luc expression by the PKA signalling activator IBMX shows that ERE-luc is responsive to ligand-independent activation, suggesting a possible mechanism of glyphosate-mediated activation. Our study reveals that glyphosate, but not other components present in GBHs, can activate ERα in vitro, albeit at relatively high concentrations. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Phytotoxicity of glyphosate in the germination of and its effect on germinated seedlings

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Subinoy Mondal

2017-08-01

Full Text Available The present study evaluated the effects of glyphosate on Pisum sativum germination as well as its effect on the physiology and biochemistry of germinated seedlings. Different physico-chemical biomarkers, viz., chlorophyll, root and shoot length, total protein and soluble sugar, along with sodium and potassium concentration, were investigated in germinated seedlings at different glyphosate concentrations. This study reports the influence of different concentrations of glyphosate on pea seeds and seedlings. Physicochemical biomarkers were significantly changed by glyphosate exposure after 15 days. The germination of seedlings under control conditions (0 mg/L was 100% after 3 days of treatment but at 3 and 4 mg/L glyphosate, germination was reduced to 55 and 40%, respectively. Physiological parameters like root and shoot length decreased monotonically with increasing glyphosate concentration, at 14 days of observation. Average root and shoot length (n=30 in three replicates were reduced to 14.7 and 17.6%, respectively, at 4 mg/L glyphosate. Leaf chlorophyll content also decreased, with a similar trend to root and shoot length, but the protein content initially decreased and then increased with an increase in glyphosate concentration to 3 mg/L. The study suggests that glyphosate reduces the soluble sugar content significantly, by 21.6% (v/v. But internal sodium and potassium tissue concentrations were significantly altered by glyphosate exposure with increasing concentrations of glyphosate. Biochemical and physiological analysis also supports the inhibitory effect of glyphosate on seed germination and biochemical effects on seedlings.

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

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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

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

EPA's evaluation of the carcinogenic potential of glyphosate

Science.gov (United States)

Recently, several international agencies have evaluated the carcinogenic potential of glyphosate. In March 2015, the International Agency for Research on Cancer (IARC), a subdivision of the World Health Organization (WHO), determined that glyphosate was a probable carcinogen (gro...

Glyphosate in the general population and in applicators: a critical review of studies on exposures.

Science.gov (United States)

Solomon, Keith R

2016-09-01

The recent classification of glyphosate as a probable human carcinogen by the International Agency for Research on Cancer (IARC) was arrived at without a detailed assessment of exposure. Glyphosate is widely used as an herbicide, which might result in exposures of the general public and applicators. Exposures were estimated from information in the open literature and unpublished reports provided by Monsanto Company. Based on the maximum measured concentration in air, an exposure dose of 1.04 × 10  -   6  mg/kg body mass (b.m.)/d was estimated. Assuming consumption of surface water without treatment, the 90th centile measured concentration would result in a consumed dose of 2.25 × 10  -   5  mg/kg b.m./d. Estimates by the Food and Agriculture Organization of the United Nations (FAO) of consumed doses in food provided a median exposure of 0.005 mg/kg b.m./d (range 0.002-0.013). Based on tolerance levels, the conservative estimate by the US Environmental Protection Agency (US EPA) for exposure of the general population via food and water was 0.088 mg/kg b.m./d (range 0.058-0.23). For applicators, 90th centiles for systemic exposures based on biomonitoring and dosimetry (normalized for penetration through the skin) were 0.0014 and 0.021 mg/kg b.m./d, respectively. All of these exposures are less than the reference dose and the acceptable daily intakes proposed by several regulatory agencies, thus supporting a conclusion that even for these highly exposed populations the exposures were within regulatory limits.

[Mutual Effect on Determination of Gibberellins and Glyphosate in Groundwater by Spectrophotometry].

Science.gov (United States)

Zhang, Li; Chen, Liang; Liu, Fei

2015-04-01

In the present study, a spectrophotometry method for the simultaneous determination of gibberellins (GA3) and glyphosate in groundwater was established and optimized. In addition, the mutual effect on simultaneous determination of GA3 and glyphosate was studied. Based on the experiment, good linearity (R2 > 0.99) was obtained for GA3 in the range of 0-20 and 0-100 µg and for glyphosate in the range of 0-8 and 5-15 µg. The method's detection limit (MDL) of GA3 and glyphosate was 0.48 and 0.82 µg, respectively; and the recovery rates of 15 to 150 µg GA3 and 3 to 10 µg glyphosate in all samples at a spiked level were 71.3% ± 1.9% and 98.4% ± 8.1%, respectively. No obvious influence of glyphosate (0-100 mg · L(-1)) on the recovery rates of GA3 was observed, but the presence of glyphosate could cause slight determination precision decrease of GA3. Meanwhile, adding 2 mg · L(-1) GA3 can increase the recovery rate of glyphosate.

Estimating foliar nitrogen in Eucalyptus using vegetation indexes

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Luiz Felipe Ramalho de Oliveira

Full Text Available ABSTRACT Nitrogen (N has commonly been applied in Eucalyptus stands in Brazil and it has a direct relation with biomass production and chlorophyll content. Foliar N concentrations are used to diagnose soil and plant fertility levels and to develop N fertilizer application rates. Normally, foliar N is obtained using destructive methods, but indirect analyses using Vegetation Indexes (VIs may be possible. The aim of this work was to evaluate VIs to estimate foliar N concentration in three Eucalyptus clones. Lower crown leaves of three clonal Eucalyptus plantations (25 months old were classified into five color patterns using the Munsell Plant Tissue Color Chart. For each color, N concentration was determined by the Kjeldahl method and foliar reflectance was measured using a CI-710 Miniature Leaf Spectrometer. Foliar reflectance data were used to obtain the VIs and the VIs were used to estimate N concentrations. In the visible region, the relationship between N concentration and reflectance percentage was negative. The highest correlations between VIs and N concentrations were obtained by the Inflection Point Position (IPP, r = 0.97, Normalized Difference Red-Edge (reNDVI, r = 0.97 and Modified Red-Edge Normalized Difference Vegetation Index (mNDI, r = 0.97. Vegetation indexes on the red edge region provided the most accurate estimates of foliar N concentration. The reNDVI index provided the best N concentration estimates in leaves of different colors of Eucalyptus urophylla × grandis and Eucalyptus urophylla × urophylla (R2 = 0.97 and RMSE = 0.91 g kg−1.

Effects of Foliar Selenite on the Nutrient Components of Turnip (Brassica rapa var. rapa Linn.

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Xiong Li

2018-03-01

Full Text Available We administered foliar applications of 50, 100, and 200 mg L−1 selenium (Se, selenite on turnip (Brassica rapa var. rapa Linn. and detected the changes in the main nutrient components in fleshy roots. Results showed that the foliar application of Se (IV significantly increased the Se content in turnip, and Se (IV positively affected the uptake of several mineral elements, including magnesium, phosphorus, iron, zinc, manganese, and copper. Se (IV treatments also improved the synthesis of protein and multiple amino acids instead of crude fat and total carbohydrate in turnip, indicating that the foliar application of Se (IV could enhance Se biofortification in turnip and promote its nutritional value. We recommended 50–100 mg L−1 Se treatment for foliar application on turnip based on the daily intake of Se for adults (96–139 μg person−1 day−1 and its favorable effects on the nutrient components of turnip.

Effects of foliar selenite on the nutrient components of turnip (Brassica rapa var. rapa Linn.)

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Li, Xiong; Li, Boqun; Yang, Yongping

2018-03-01

We administered foliar applications of 50, 100 and 200 mg L‑1 selenium (Se, selenite) on turnip (Brassica rapa var. rapa Linn.) and detected the changes in the main nutrient components in fleshy roots. Results showed that the foliar application of Se (Ⅳ) significantly increased the Se content in turnip, and Se (Ⅳ) positively affected the uptake of several mineral elements, including magnesium, phosphorus, iron, zinc, manganese and copper. Se (Ⅳ) treatments also improved the synthesis of protein and multiple amino acids instead of crude fat and total carbohydrate in turnip, indicating that the foliar application of Se (Ⅳ) could enhance Se biofortification in turnip and promote its nutritional value. We recommended 50–100 mg L‑1 Se treatment for foliar application on turnip based on the daily intake of Se for adults (96–139 µg person‑1 day‑1) and its favourable effects on the nutrient components of turnip.

Glyphosate and aminomethylphosphonic acid are not detectable in human milk.

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McGuire, Michelle K; McGuire, Mark A; Price, William J; Shafii, Bahman; Carrothers, Janae M; Lackey, Kimberly A; Goldstein, Daniel A; Jensen, Pamela K; Vicini, John L

2016-05-01

Although animal studies have shown that exposure to glyphosate (a commonly used herbicide) does not result in glyphosate bioaccumulation in tissues, to our knowledge there are no published data on whether it is detectable in human milk and therefore consumed by breastfed infants. We sought to determine whether glyphosate and its metabolite aminomethylphosphonic acid (AMPA) could be detected in milk and urine produced by lactating women and, if so, to quantify typical consumption by breastfed infants. We collected milk (n = 41) and urine (n = 40) samples from healthy lactating women living in and around Moscow, Idaho and Pullman, Washington. Milk and urine samples were analyzed for glyphosate and AMPA with the use of highly sensitive liquid chromatography-tandem mass spectrometry methods validated for and optimized to each sample matrix. Our milk assay, which was sensitive down to 1 μg/L for both analytes, detected neither glyphosate nor AMPA in any milk sample. Mean ± SD glyphosate and AMPA concentrations in urine were 0.28 ± 0.38 and 0.30 ± 0.33 μg/L, respectively. Because of the complex nature of milk matrixes, these samples required more dilution before analysis than did urine, thus decreasing the sensitivity of the assay in milk compared with urine. No difference was found in urine glyphosate and AMPA concentrations between subjects consuming organic compared with conventionally grown foods or between women living on or near a farm/ranch and those living in an urban or suburban nonfarming area. Our data provide evidence that glyphosate and AMPA are not detectable in milk produced by women living in this region of the US Pacific Northwest. By extension, our results therefore suggest that dietary glyphosate exposure is not a health concern for breastfed infants. This study was registered at clinicaltrials.gov as NCT02670278. © 2016 American Society for Nutrition.

Root-Zone Glyphosate Exposure Adversely Affects Two Ditch Species

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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.

Sorption and desorption of glyphosate in Mollisols and Ultisols soils of Argentina.

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Gómez Ortiz, Ana Maria; Okada, Elena; Bedmar, Francisco; Costa, José Luis

2017-10-01

In Argentina, glyphosate use has increased exponentially in recent years as a result of the widespread adoption of no-till management combined with genetically modified glyphosate-resistant crops. This massive use of glyphosate has created concern about its potential environmental impact. Sorption-desorption of glyphosate was studied in 3 Argentinean soils with contrasting characteristics. Glyphosate sorption isotherms were modeled using the Freundlich equation to estimate the sorption coefficient (K f ). Glyphosate sorption was high, and the K f varied from 115.6 to 1612 mg 1-1/n L 1/n /kg. Cerro Azul soil had the highest glyphosate sorption capacity as a result of a combination of factors such as higher clay content, cation exchange capacity, total iron, and aluminum oxides, and lower available phosphorus and pH. Desorption isotherms were also modeled using the Freundlich equation. In general, desorption was very low (glyphosate strongly sorbs to the soils and that it is almost an irreversible process. Anguil soil had a significantly higher desorption coefficient (K fd ) than the other soils, associated with its lower clay content and higher pH and phosphorus. Glyphosate high sorption and low desorption to the studied soils may prevent groundwater contamination. However, it may also affect its bioavailability, increasing its persistence and favoring its accumulation in the environment. The results of the present study contribute to the knowledge and characterization of glyphosate retention in different soils. Environ Toxicol Chem 2017;36:2587-2592. © 2017 SETAC. © 2017 SETAC.

Circular RNA expression profiles in hippocampus from mice with perinatal glyphosate exposure.

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Yu, Ning; Tong, Yun; Zhang, Danni; Zhao, Shanshan; Fan, Xinli; Wu, Lihui; Ji, Hua

2018-05-19

Glyphosate is the active ingredient in numerous herbicide formulations. The roles of glyphosate in embryo-toxicity and neurotoxicity have been reported in human and animal models. Recently, several studies have reported evidence linking neurodevelopmental disorders (NDDs) with gestational glyphosate exposure. However, the role of glyphosate in neuronal development is still not fully understood. Our previous study found that perinatal glyphosate exposure resulted in differential microRNA expression in the prefrontal cortex of mouse offspring. However, the mechanism of glyphosate-induced neurotoxicity in the developing brain is still not fully understood. Considering the pivotal role of Circular RNAs (circRNAs) in the regulation of gene expression, a circRNA microarray method was used in this study to investigate circRNA expression changes in the hippocampus of mice with perinatal glyphosate exposure. The circRNA microarrays revealed that 663 circRNAs were significantly altered in the perinatal glyphosate exposure group compared with the control group. Among them, 330 were significantly upregulated, and the other 333 were downregulated. Furthermore, the relative expression levels of mmu-circRNA-014015, mmu-circRNA-28128 and mmu-circRNA-29837 were verified using quantitative real-time polymerase chain reaction (qRT-PCR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses demonstrated that stress-associated steroid metabolism pathways, such as aldosterone synthesis and secretion pathways, may be involved in the neurotoxicity of glyphosate. These results showed that circRNAs are aberrantly expressed in the hippocampus of mice with perinatal glyphosate exposure and play potential roles in glyphosate-induced neurotoxicity. Copyright © 2018 Elsevier Inc. All rights reserved.

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

Science.gov (United States)

Samsel, Anthony

2013-01-01

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

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

Evaluation of estrogen receptor alpha activation by glyphosate-based herbicide constituents

OpenAIRE

Mesnage, Robin; Phedonos, Alexia; Biserni, Martina; Arno, Matthew; Balu, Sucharitha; Corton, J. Christopher; Ugarte, Ricardo; Antoniou, Michael N.

2017-01-01

The safety, including endocrine disruptive capability, of glyphosate-based herbicides (GBHs) is a matter of intense debate. We evaluated the estrogenic potential of glyphosate, commercial GBHs and polyethoxylated tallowamine adjuvants present as co-formulants in GBHs. Glyphosate (≥10,000 μg/L or 59 μM) promoted proliferation of estrogen-dependent MCF-7 human breast cancer cells. Glyphosate also increased expression of an estrogen response element-luciferase reporter gene (ERE-luc) in T47D-KBl...

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

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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.

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

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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.

EFFECTIVENESS OF GLYPHOSATE AND 2.4 D AMIN HERBICIDES TO CONTROL WEEDS UNDER Shorea selanica Bl. PLANTATION IN CARITA TRIAL GARDEN, BANTEN

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Ari Wibowo

2007-03-01

Full Text Available A trial was carried out in Carita, West Java, to identify the effectiveness of Glyphosate and 2.4 D Amin Herbicide to control weeds under Shorea selanica Bl. plantation. The trial was conducted through the application of Glyphosate and 2.4 D Amin Herbicide with dosages of 5, 6, 7, 8 and 9 liter per ha and compared with Glyphosate herbicide 5 liter per ha, manual treatment, and control (no treatment. The result showed that Glyphosate and 2.4 D Amin Herbicide could be used to control weeds in order to maintaining S. selanica Bl. plantation. Minimum dosage of 6 liter/ha was effective to control weeds such as Chromolaena odorata DC, Mikania micrantha Will, Lantana camara L, Imperata cylindrica Beauv., Melastoma malabathricum L, and Boreria latifolia Bl. Furthermore, there was no symptom of poison on S. selanica Bl. plantation after herbicide application with all dosages applied.

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

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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.

PVP capped silver nanocubes assisted removal of glyphosate from water-A photoluminescence study.

Science.gov (United States)

Sarkar, Sumit; Das, Ratan

2017-10-05

Glyphosate [N-phosphono-methylglycine (PMG)] is the most used herbicide worldwide and it has been reported very recently that Glyphosate is very harmful and can produce lots of diseases such as alzheimer and parkinson's disease, depression, cancer, infertility including genotoxic effects. As it is mostly present in stable water body and ground water system, its detection and removal is very important. Here, we have shown a fluorescence technique for the removal of glyphosate from water using chemically synthesized polyvinylpyrrolidone (PVP) silver nanocrystals. Transmission Electron Microscopy (TEM) study shows the average size of silver nanocrystals of 100nm approximately with a morphology of cubic shape. Glyphosate does not show absorption in the visible region. But both glyphosate and silver nanocrystals show strong fluorescence in the visible region. So, photoluminescence study has been successfully utilized to detect the glyphosate in water samples and on treating the glyphosate contaminated water sample with silver nanocrystals, the sample shows no emission peak of glyphosate at 458nm. Thus, this approach is a promising and very rapid method for the detection and removal of glyphosate from water samples on treatment with silver nanocubes. NMR spectra further confirms that the silver nanocrystals treated contaminated water samples are glyphosate free. Copyright © 2017 Elsevier B.V. All rights reserved.

The different behaviors of glyphosate and AMPA in compost-amended soil.

Science.gov (United States)

Erban, Tomas; Stehlik, Martin; Sopko, Bruno; Markovic, Martin; Seifrtova, Marcela; Halesova, Tatana; Kovaricek, Pavel

2018-05-04

The broad-spectrum herbicide glyphosate is one of the most widely used pesticides. Both glyphosate and its major metabolite, aminomethylphosphonic acid (AMPA), persist in waters; thus, their environmental fates are of interest. We investigated the influence of compost dose, sampling depth, moisture and saturated hydraulic conductivity (K s ) on the persistence of these substances. The amounts of AMPA quantified by triple quadrupole liquid chromatography-mass spectrometry (LC-QqQ-MS/MS) using isotopically labeled extraction standards were higher than those of glyphosate and differed among the samples. Both glyphosate and AMPA showed gradually decreasing concentrations with soil depth, and bootstrapped ANOVA showed significant differences between the contents of glyphosate and AMPA and their behavior related to different compost dosages and sampling depths. However, the compost dose alone did not cause significant differences among samples. Bayesian statistics revealed that the amounts of glyphosate and AMPA were both dependent on the sampling depth and compost dose, but differences were found when considering the physical factors of K s and moisture. Glyphosate was influenced by moisture but not K s , whereas AMPA was influenced by K s but not moisture. Importantly, we found behavioral differences between glyphosate and its major metabolite, AMPA, related to the physical properties of K s and moisture. Copyright © 2018 Elsevier Ltd. All rights reserved.

EPSPS variability, gene expression, and enzymatic activity in glyphosate-resistant biotypes of Digitaria insularis.

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Galeano, E; Barroso, A A M; Vasconcelos, T S; López-Rubio, A; Albrecht, A J P; Victoria Filho, R; Carrer, H

2016-08-12

Weed resistance to herbicides is a natural phenomenon that exerts selection on individuals in a population. In Brazil, glyphosate resistance was recently detected in Digitaria insularis. The objective of this study was to elucidate mechanisms of weed resistance in this plant, including genetic variability, allelism, amino acid substitutions, gene expression, and enzymatic activity levels. Most of these have not previously been studied in this species. D. insularis DNA sequences were used to analyze genetic variability. cDNA from resistant and susceptible plants was used to identify mutations, alleles, and 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) expression, using real-time quantitative reverse transcription-polymerase chain reaction. In addition, EPSPS activity was measured. We found a decrease in genetic variability between populations related to glyphosate application. Substitutions from proline to threonine and tyrosine to cysteine led to a decrease in EPSPS affinity for the glyphosate. In addition, the EPSPS enzymatic activity was slightly higher in resistant plants, whereas EPSPS gene expression was almost identical in both biotypes, suggesting feedback regulation at different levels. To conclude, our results suggest new molecular mechanisms used by D. insularis to increase glyphosate resistance.

Foliar glyphosate treatment alters transcript and hormone profiles in crown buds of leafy spurge and induces dwarfed and bushy phenotypes throughout its perennial life cycle

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Leafy spurge (Euphorbia esula) is an invasive weed of North America and its perennial nature is attributed to underground adventitious buds (UABs) that undergo seasonal cycles of para-, endo- and eco-dormancy. Recommended field rates of glyphosate (~1 kg/ha) destroys above-ground shoots of leafy spu...

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. Copyright © 2013 SETAC.

Comparative Metabolomic Analyses of Ipomoea lacunosa Biotypes with Contrasting Glyphosate Tolerance Captures Herbicide-Induced Differential Perturbations in Cellular Physiology.

Science.gov (United States)

Maroli, Amith S; Nandula, Vijay K; Duke, Stephen O; Gerard, Patrick; Tharayil, Nishanth

2018-02-28

Glyphosate-tolerant Ipomoea lacunosa is emerging as a problematic weed in the southeastern United States. Metabolomic profiling was conducted to examine the innate physiology and the glyphosate induced perturbations in two biotypes of I. lacunosa (WAS and QUI) that had contrasting glyphosate tolerance. Compared to the less tolerant QUI-biotype, the innate metabolism of the more tolerant WAS-biotype was characterized by a higher abundance of amino acids, and pyruvate; whereas the sugar profile of the QUI biotype was dominated by the transport sugar sucrose. Glyphosate application (80 g ae/ha) caused similar shikimate accumulation in both biotypes. Compared to QUI, in WAS, the content of aromatic amino acids was less affected by glyphosate treatment, and the content of Ala, Val, Ile, and Pro increased. However, the total sugars decreased by ∼75% in WAS, compared to ∼50% decrease in QUI. The innate, higher proportional abundance, of the transport-sugar sucrose in QUI coud partly explain the higher translocation and greater sensitivity of this biotype to glyphosate. The decrease in sugars, accompanied by an increase in amino acids could delay feedback regulation of upstream enzymes of the shikimate acid pathway in WAS, which could contribute to a greater glyphosate tolerance. Our study, through a metabolomics approach, provides complementary data that elucidates the cellular physiology of herbicide tolerance in Ipomoea lacunosa biotypes.

Studies on the effects of application of different foliar fertilizer materials, crop residue and inter cropping on Banana plants

Energy Technology Data Exchange (ETDEWEB)

Hassan, Yusuf Munim [Faculty of Agriculture, University of Khartoum, Khartoum (Sudan)

1997-12-31

Five separate experiments were conducted at university of Khartoum demonstration farm during 1993 to 1995 under both orchard and nursery conditions to evaluate the effect of foliar application of different fertilizers, use of crop residue and intercropping on banana (dwarf cavendish). In the first experiment, the effects of foliar application of different concentrations of potassium solution (38%) were studied. The results indicated that application of all concentrations resulted in greater increases in overall growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the second experiment, the effects of three different foliar fertilizers, namely, compound cryst, fetrilon comb-2 and x-garden were investigated. The results revealed that all fertilizers gave greater values of all growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the third experiment, the effect of four different fertilizer materials containing different combinations of NPK on growth parameters and nutrient elements contents of leaves of banana suckers grown under nursery conditions was evaluated. The results revealed that all fertilizer materials gave greater increases of growth parameters over the control as well as higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents. In the fourth experiment, the effect of different concentrations of N{sub 19}, P{sub 19}, K{sub 19} fertilizers on growth characteristics and nutrient elements contents of leaves of banana

Studies on the effects of application of different foliar fertilizer materials, crop residue and inter cropping on Banana plants

International Nuclear Information System (INIS)

Hassan, Yusuf Munim

1996-01-01

Five separate experiments were conducted at university of Khartoum demonstration farm during 1993 to 1995 under both orchard and nursery conditions to evaluate the effect of foliar application of different fertilizers, use of crop residue and intercropping on banana (dwarf cavendish). In the first experiment, the effects of foliar application of different concentrations of potassium solution (38%) were studied. The results indicated that application of all concentrations resulted in greater increases in overall growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the second experiment, the effects of three different foliar fertilizers, namely, compound cryst, fetrilon comb-2 and x-garden were investigated. The results revealed that all fertilizers gave greater values of all growth parameters, higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents, higher values of yield and yield components , finger length of both plant crop and the first ratoon crop and reduction of time from planting to flowering and from flowering to harvesting of both plant crop and the first crop compared to the control. In the third experiment, the effect of four different fertilizer materials containing different combinations of NPK on growth parameters and nutrient elements contents of leaves of banana suckers grown under nursery conditions was evaluated. The results revealed that all fertilizer materials gave greater increases of growth parameters over the control as well as higher leaf-N, P, K, Ca, Mg, Mn, Fe, Zn and Cu contents. In the fourth experiment, the effect of different concentrations of N 19 , P 19 , K 19 fertilizers on growth characteristics and nutrient elements contents of leaves of banana suckers was

Malabsorption of mineral nutrients and effects of foliar fertilization on continuously cropped capsicum annuum l. var. annuum

International Nuclear Information System (INIS)

Ye, X.H.; Zhao, Z.L.; Zhao, Z.L.; Zhao, H.B.

2014-01-01

Cayenne pepper (C. annuum var. annuum) cultivar known as line No. 5 was used to establish a reference baseline for fertilization experiments under conditions of continuous cropping versus crop rotation. The effects of continuous cropping on absorption of 11 essential nutrient elements and fruit yield were studied. Concurrently, we also examined the effects of foliar application of urea + KH/sub 2/ PO/sub 4/ and Fe + B + Zn + Mn on nutrient absorption due to continuous cropping. The results showed that, compared with peppers grown in rotation soil, continuous cropping affected the uptake of eight elements (P, K, Mg, Fe, B, Zn, Mn, Cu) and transport of these elements to the aerial parts of the plant, although the element concentrations in continuous cropping soil were not lower than those in rotation soil. Continuous cropping caused a decline in fruit yield. The impact of continuous cropping on the uptake of trace elements was greater than it was for macro elements. Foliar application of urea + KH/sub 2/ PO/sub 4/ significantly improved the P, Mg, Fe, and Mo content of continuously-cropped pepper plants, but did not significantly improve the content of N and K, and there was an antagonistic effect on Zn uptake. Foliar application of Fe + B + Zn + Mn, significantly increased the Fe, B, Zn, Mn, and P content in the plants; Ca uptake in the leaves and fruits was promoted to a certain degree, but there was obvious antagonism toward Mo and Cu uptake in the stems, leaves and fruits. Pepper fruit yields were significantly increased by foliar application of urea + KH/sub 2/ PO/sub 4/ or foliar application of Fe + B + Zn + Mn. However the effects of foliar application of Fe + B + Zn + Mn on increased production were significantly better than the effects of foliar application of urea + KH/sub 2/ PO/sub 4/. (author)

Improvement of antioxidant activities and yield of spring maize through seed priming and foliar application of plant growth regulators under heat stress conditions

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Ijaz Ahmad

2017-03-01

Full Text Available Heat stress during reproductive and grain filling phases adversely affects the growth of cereals through reduction in grain’s number and size. However, exogenous application of antioxidants, plant growth regulators and osmoprotectants may be helpful to minimize these heat induced yield losses in cereals. This two year study was conducted to evaluate the role of exogenous application of ascorbic acid (AsA, salicylic acid (SA and hydrogen peroxide (H2O2 applied through seed priming or foliar spray on biochemical, physiological, morphological and yield related traits, grain yield and quality of late spring sown hybrid maize. The experiment was conducted in the spring season of 2007 and 2008. We observed that application of AsA, SA and H2O2 applied through seed priming or foliar spray improved the physiological, biochemical, morphological and yield related traits, grain yield and grain quality of late spring sown maize in both years. In both years, we observed higher superoxide dismutase (SOD, catalase (CAT and peroxidase (POD activity in the plants where AsA, SA and H2O2were applied through seed priming or foliar spray than control. Membrane stability index (MSI, relative water contents (RWC, chlorophyll contents, grain yield and grain oil contents were also improved by exogenous application of AsA, SA and H2O2 in both years. Seed priming of AsA, SA and H2O2was equally effective as the foliar application. In conclusion, seed priming with AsA, SA and H2O2 may be opted to lessen the heat induced yield losses in late sown spring hybrid maize. Heat tolerance induced by ASA, SA and H2O2 may be attributed to increase in antioxidant activities and MSI which maintained RWC and chlorophyll contents in maize resulting in better grain yield in heat stress conditions.

A glyphosate micro-emulsion formulation displays teratogenicity in Xenopus laevis.

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Bonfanti, Patrizia; Saibene, M; Bacchetta, R; Mantecca, P; Colombo, A

2018-02-01

Glyphosate is the active ingredient in broad-spectrum herbicide formulations used in agriculture, domestic area and aquatic weed control worldwide. Its market is growing steadily concurrently with the cultivation of glyphosate-tolerant transgenic crops and emergence of weeds less sensitive to glyphosate. Ephemeral and lentic waters near to agricultural lands, representing favorite habitats for amphibian reproduction and early life-stage development, may thus be contaminated by glyphosate based herbicides (GBHs) residues. Previous studies on larval anuran species highlighted increased mortality and growth effects after exposure to different GBHs in comparison to glyphosate itself, mainly because of the surfactants such as polyethoxylated tallow amine present in the formulations. Nevertheless, these conclusions are not completely fulfilled when the early development, characterized by primary organogenesis events, is considered. In this study, we compare the embryotoxicity of Roundup ® Power 2.0, a new GBH formulation currently authorized in Italy, with that of technical grade glyphosate using the Frog Embryo Teratogenesis Assay-Xenopus (FETAX). Our results evidenced that glyphosate was not embryolethal and only at the highest concentration (50 mg a.e./L) caused edemas. Conversely, Roundup ® Power 2.0 exhibited a 96 h LC50 of 24.78 mg a.e./L and a 96 h EC50 of 7.8 mg a.e./L. A Teratogenic Index of 3.4 was derived, pointing out the high teratogenic potential of the Roundup ® Power 2.0. Specific concentration-dependent abnormal phenotypes, such as craniofacial alterations, microphthalmia, narrow eyes and forebrain regionalization defects were evidenced by gross malformation screening and histopathological analysis. These phenotypes are coherent with those evidenced in Xenopus laevis embryos injected with glyphosate, allowing us to hypothesize that the teratogenicity observed for Roundup ® Power 2.0 may be related to the improved efficacy in delivering

Uptake, Translocation, Metabolism, and Distribution of Glyphosate in Nontarget Tea Plant (Camellia sinensis L.).

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Tong, Mengmeng; Gao, Wanjun; Jiao, Weiting; Zhou, Jie; Li, Yeyun; He, Lili; Hou, Ruyan

2017-09-06

The uptake, translocation, metabolism, and distribution behavior of glyphosate in nontarget tea plant were investigated. The negative effects appeared to grown tea saplings when the nutrient solution contained glyphosate above 200 mg L -1 . Glyphosate was highest in the roots of the tea plant, where it was also metabolized to aminomethyl phosphonic acid (AMPA). The glyphosate and AMPA in the roots were transported through the xylem or phloem to the stems and leaves. The amount of AMPA in the entire tea plant was less than 6.0% of the amount of glyphosate. The glyphosate level in fresh tea shoots was less than that in mature leaves at each day. These results indicated that free glyphosate in the soil can be continuously absorbed by, metabolized in, and transported from the roots of the tea tree into edible leaves, and therefore, free glyphosate residues in the soil should be controlled to produce teas free of glyphosate.

MORPHOLOGICAL AND PHYSIOLOGICAL CHANGES ON Schizolobium parahybaVAR .Amazonicum(HUBER EX DUCKE BARNEBY PLANTS INTOXICATED BY GLYPHOSATE

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Kaléo Dias Pereira

2017-06-01

Full Text Available The objective of this study was to evaluate the morphological and physiological changes in paricá plants (Schizolobium parahyba var. amazonicum intoxicated by glyphosate. The experiment was conducted in a protected environment using paricá plants during their planting stage, which were intoxicated with increasing doses of glyphosate: 0 (control; 43.2; 86.2; 129.6 and 172.8 g.ha-1. At 7 and 21 days after the application of the herbicide, the photosynthesis, transpiration, stomatal conductance and leaf temperature were measured. The visual intoxication degree and the growth of the shoot and the root of the plants were evaluated 21 days after the application. Paricá shows symptoms of visual intoxication characterized by chlorosis/winding, evolving to necrosis/abscission of the youngest leaflets. The growth of the stem and the roots of the intoxicated plants is preserved; however, an expressive leaf loss occurs, and paricá may have adaptation mechanisms to tolerate the action of the herbicide molecule. The photosynthesis decrease promoted by an indirect action of glyphosate represents the main reduction on the growth of plants. The decrease on the stomatal conductance, which was the most sensitive physiological variable to glyphosate, resulted in lower transpiration rates, which, consequently, caused increases on the leaf temperature.

Facts and Fallacies in the Debate on Glyphosate Toxicity

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Robin Mesnage

2017-11-01

Full Text Available The safety profile of the herbicide glyphosate and its commercial formulations is controversial. Reviews have been published by individuals who are consultants and employees of companies commercializing glyphosate-based herbicides in support of glyphosate’s reapproval by regulatory agencies. These authors conclude that glyphosate is safe at levels below regulatory permissible limits. In contrast, reviews conducted by academic scientists independent of industry report toxic effects below regulatory limits, as well as shortcomings of the current regulatory evaluation of risks associated with glyphosate exposures. Two authors in particular (Samsel and Seneff have published a series of commentaries proposing that long-term exposure to glyphosate is responsible for many chronic diseases (including cancers, diabetes, neuropathies, obesity, asthma, infections, osteoporosis, infertility, and birth defects. The aim of this review is to examine the evidential basis for these claimed negative health effects and the mechanisms that are alleged to be at their basis. We found that these authors inappropriately employ a deductive reasoning approach based on syllogism. We found that their conclusions are not supported by the available scientific evidence. Thus, the mechanisms and vast range of conditions proposed to result from glyphosate toxicity presented by Samsel and Seneff in their commentaries are at best unsubstantiated theories, speculations, or simply incorrect. This misrepresentation of glyphosate’s toxicity misleads the public, the scientific community, and regulators. Although evidence exists that glyphosate-based herbicides are toxic below regulatory set safety limits, the arguments of Samsel and Seneff largely serve to distract rather than to give a rational direction to much needed future research investigating the toxicity of these pesticides, especially at levels of ingestion that are typical for human populations.

Facts and Fallacies in the Debate on Glyphosate Toxicity

Science.gov (United States)

Mesnage, Robin; Antoniou, Michael N.

2017-01-01

The safety profile of the herbicide glyphosate and its commercial formulations is controversial. Reviews have been published by individuals who are consultants and employees of companies commercializing glyphosate-based herbicides in support of glyphosate’s reapproval by regulatory agencies. These authors conclude that glyphosate is safe at levels below regulatory permissible limits. In contrast, reviews conducted by academic scientists independent of industry report toxic effects below regulatory limits, as well as shortcomings of the current regulatory evaluation of risks associated with glyphosate exposures. Two authors in particular (Samsel and Seneff) have published a series of commentaries proposing that long-term exposure to glyphosate is responsible for many chronic diseases (including cancers, diabetes, neuropathies, obesity, asthma, infections, osteoporosis, infertility, and birth defects). The aim of this review is to examine the evidential basis for these claimed negative health effects and the mechanisms that are alleged to be at their basis. We found that these authors inappropriately employ a deductive reasoning approach based on syllogism. We found that their conclusions are not supported by the available scientific evidence. Thus, the mechanisms and vast range of conditions proposed to result from glyphosate toxicity presented by Samsel and Seneff in their commentaries are at best unsubstantiated theories, speculations, or simply incorrect. This misrepresentation of glyphosate’s toxicity misleads the public, the scientific community, and regulators. Although evidence exists that glyphosate-based herbicides are toxic below regulatory set safety limits, the arguments of Samsel and Seneff largely serve to distract rather than to give a rational direction to much needed future research investigating the toxicity of these pesticides, especially at levels of ingestion that are typical for human populations. PMID:29226121

Effects of urea foliar application and of ammonium sulphate and urea applied to the soil on yield and N utilization by beans (Phaseolus vulgaris L.)

International Nuclear Information System (INIS)

Muraoka, T.; Victoria, R.L.; Oliveira, J.P.; Boaretto, A.E.

1984-01-01

The effects of nitrogen applied to the soil (as ammonium sulphate and urea) and foliar application of urea supplementing or not the soil application, on bean yield and nitrogen utilization are studied in a cerrado soil. Labelled ammonium sulphate is applied at the rate of 20Kg N/ha at seeding or 15 or 25 days after seeding and 40 Kg N/ha at seeding or in two different applications. Labelled urea is applied at the rate of 20kg N/ha at seeding and 40 Kg N/ha splitted. Foliar application is done at 15,22, 29,36 and 45 days after seeding, with 2% urea solution labelled with 10% 15 N. (M.A.C.) [pt

Effects of a combination of elicitation and precursor feeding on grape amino acid composition through foliar applications to Garnacha vineyard.

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Gutiérrez-Gamboa, Gastón; Portu, Javier; López, Rosa; Santamaría, Pilar; Garde-Cerdán, Teresa

2018-04-01

Vine foliar applications of phenylalanine (Phe) or methyl jasmonate (MeJ) could improve the synthesis of secondary metabolites. However, there are no reports focusing on the effects of elicitation supported by precursor feeding on must amino acid composition in grapevines. The aim of this research was to study the effect of the elicitation of methyl jasmonate (MeJ) supported by phenylalanine (Phe) as a precursor feeding (MeJ+Phe) and its application individually on must amino acid composition. Results showed that foliar Phe and MeJ treatments decreased the concentration of most of the studied amino acids with respect to the control (p≤0.05). MeJ+Phe treatment did not affect must nitrogen content. Musts obtained from MeJ+Phe showed higher concentration of several amino acids than samples from Phe and MeJ applications. Therefore, other sources of precursor feeding could support elicitation, to improve amino acid composition and be considered as a tool for viticulture. Copyright © 2017 Elsevier Ltd. All rights reserved.

Glyphosate Use in Forest Plantations Uso de Glifosato en Plantaciones Forestales

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Marcelo Kogan

2010-12-01

Full Text Available Under Chilean conditions the lack of weed control at forest tree establishment results in an average of at least 60% less biomass accumulation during the first year of growth of radiate pine or eucaliptus, and glyphosate offers a series of advantages in forestry weed management because its activity in both herbaceous weed groups, monocots and dicots, as well as annuals, biennials and perennials. Also, its efficacy in woody undesirable vegetation makes glyphosate a very important herbicide that can be applied to control herbaceous and woody weeds as pre-planting and during the second or third years of trees growth as strip applications. The aim of this review is to discuss the main uses of glyphosate in reforestation worldwide, during the first 2 yr after tree establishment, as broadcast application over the top of the forest trees and the most important factors that could affect glyphosate efficacy as a forest herbicide, like weed growth stage, application technique, volume and water quality, rainfastness, dew effect and the use of extra adjuvant with formulated glyphosate.Bajo las condiciones chilenas la falta de control de malezas al establecimiento de los árboles resulta en un promedio de al menos 60% menos acumulación de biomasa durante el primer año de crecimiento de pino radiata o eucalipto, y glifosato ofrece una serie de ventajas en el manejo de malezas forestales debido a su actividad en ambos grupos de malezas herbáceas, monocotiledóneas y dicotiledóneas, así como anuales, bianuales y perennes. Además, su eficacia en la vegetación leñosa indeseable hace al glifosato un herbicida muy importante que puede ser aplicado para controlar malezas herbáceas y leñosas en pre-plantación y durante el segundo o tercer año de crecimiento de los árboles como aplicaciones en franja. El objetivo de esta revisión es discutir los principales usos de glifosato en reforestación a lo largo del mundo, durante los primeros 2 años despu

Simulated drift effect of glyphosate in different parts of Eucalyptus grandis plantsEfeito da deriva simulada de glyphosate em diferentes partes da planta de Eucalyptus grandis

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Maria Renata Rocha Pereira

2012-10-01

Full Text Available The present work aimed to evaluate the effects of simulated drift of glyphoste on Eucalyptus grandis, through the application of low doses in different parts of the plant. The experimental design was a randomized block design with five replications. The treatments were glyphosate application at 0; 30; 60; 90 e 120 g a.e. ha-1 of the commercial formulation Scout®. Three forms of application were used: applying on leaf, on stem, and on the entire plant (leaf + stem. For leaf application, stems were covered with plastic ribbons to protect them from the solution; the same was made with plants that were sprayed on stems, covering leaf with plastic bag. The application was carried out in an armed stationary spray tips XR 11002 VS, with 183 KPa pressure in volume of 200 L ha-1. The eucalyptus plants receiving applications in leaves and whole plant (leaves + stem showing effects of intoxication are more intense about the plants that received the stem applications only. However, there may be increases in height growth and total dry mass of eucalyptus plants in applications of 30 g a.e. ha-1 glyphosate.No presente trabalho objetivou-se avaliar os efeitos da deriva simulada de glyphoste em plantas de Eucalyptus grandis, por meio da aplicação de doses reduzidas em diferentes partes da planta. Utilizouse o delineamento inteiramente casualizado, com cinco repetições. Os tratamentos foram constituídos da aplicação de 0; 30; 60; 90 e 120 g e.a.ha-1 de glyphosate, da formulação comercial Scout®. A aplicação foi realizada de três formas: aplicação sobre as folhas, no caule e na planta inteira (folha + caule. Para a aplicação nas folhas o caule foi coberto com fitas plásticas para evitar que fosse atingido pela solução, e o mesmo foi feito com as plantas que receberam pulverização no caule, cobrindo as folhas com saco plástico. A aplicação foi realizada em um pulverizador estacionário, munido de pontas XR 11002 VS, com pressão de 183

Glyphosate and AMPA in U.S. streams, groundwater, precipitation and soils

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Battaglin, William A.; Meyer, Michael T.; Kuivila, Kathryn; Dietze, Julie E.

2014-01-01

Herbicides containing glyphosate are used in more than 130 countries on more than 100 crops. In the United States (U.S.), agricultural use of glyphosate [N-(phosphonomethyl)glycine] has increased from less than 10,000 metric tons per year (active ingredient) in 1993 to more than 70,000 metric tons per year in 2006. In 2006, glyphosate accounted for about 20 percent of all herbicide use (by weight of active ingredient). Glyphosate formulations such as Roundup® are used in homes and in agriculture. Part of the reason for the popularity of glyphosate is the perception that it is an “environmentally benign” herbicide that has low toxicity and little mobility or persistence in the environment. The U.S. Geological Survey developed an analytical method using liquid chromatography/tandem mass spectrometry that can detect small amounts of glyphosate and its primary degradation product aminomethylphosphonic acid (AMPA) in water and sediment. Results from more than 2,000 samples collected from locations distributed across the U.S. indicate that glyphosate is more mobile and occurs more widely in the environment than was previously thought. Glyphosate and AMPA were detected (reporting limits between 0.1 and 0.02 micrograms per liter) in samples collected from surface water, groundwater, rainfall, soil water, and soil, at concentrations from less than 0.1 to more than 100 micrograms per liter. Glyphosate was detected more frequently in rain (86%), ditches and drains (71%), and soil (63%); and less frequently in groundwater (3%) and large rivers (18%). AMPA was detected more frequently in rain (86%), soil (82%), and large rivers (78%); and less frequently in groundwater (8%) and wetlands or vernal pools (37%). Most observed concentrations of glyphosate were well below levels of concern for humans or wildlife, and none exceeded the U.S. Environmental Protection Agency’s Maximum Contaminant Level of 700 micrograms per liter. However, the ecosystem effects of chronic low

[Study of the effect of occupational exposure to glyphosate on hepatorenal function].

Science.gov (United States)

Zhang, F; Pan, L P; Ding, E M; Ge, Q J; Zhang, Z H; Xu, J N; Zhang, L; Zhu, B L

2017-07-06

Objective: To explore the effect of occupational exposure to glyphosate on hepatorenal function. Methods: 526 workers who were occupationally exposed to glyphosate from 5 glyphosate-producing factories were selected as cases; and another 442 administrative staffs who were not exposed to glyphosate were selected as controls from April to November, 2014. All the subjects accepted occupational health examination. The concentration level of glyphosate in the air of workshop was detected and the time weighted average concentration (TWA) was calculated. And analyze the difference of hepatorenal fuction between case group and control group. Result: The age of the subjects in the case and control groups were separately (35.6±10.3), (34.3±9.7) years old, with the length of working for (6.5±5.7), (7.7±6.8) years. The TWA of glyphosate in the case group was between Glyphosate can affect the hepatic and renal function among occupational exposure population, and there was an association between the effect and the exposure dose.

Tolerância do Tifton 85 (Cynodon spp. e da Brachiaria brizantha ao glyphosate Tifton 85 (Cynodon spp. and Brachiaria brizantha tolerance to glyphosate

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M.V. Santos

2008-06-01

.440; 2.160; and 2.880 g ha-1 of glyphosate were tested in to an experiment arranged in a randomized block design, with four replicates divided into 3.5 m x 3.0 m, totaling 10.5 m², and only 7.5 m² of useful area. Herbicide efficiency in B. brizantha control and intoxication level on Tifton 85 plants were evaluated at 15, 30 and 60 days after application (DAA, following the scale from 0 (absence of control and/or intoxication to 100 (total control or plant death. At 300 DAA, the forage plants of both species were cut and dried to evaluate production and sprouting potential. Control superior to 90% of B. brizantha plants was observed from 1,473.75 and 1,721.25 g ha-1 of glyphosate rates, respectively at 30 and 60 DAA. The intoxication of Tifton 85 plants referring to B. brizantha control rates were 24.90 and 4.13%, respectively. At 60 DAA, 18.22% of Tifton 85 plants intoxication was observed at the highest rate evaluated (2.880 g ha-1 of glyphosate. Absence of B. brizantha dry matter production occurred at 300 DAA, at 2.160 g ha¹ herbicide rate as a result of efficient control. Results showed higher tolerance of Tifton 85 plants to glyphosate in relation to B. brizantha plants, allowing this species control in established Tifton 85 pasture, with no damage to the cultivated forage.

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

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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

Factors affecting the fate and transport of glyphosate and AMPA into surface waters of agricultural watersheds in the United States and Europe

Science.gov (United States)

Coupe, R.; Kalkhoff, S.; Capel, P.; Gregoire, C.

2012-04-01

Glyphosate [N-(phosphonomethyl)glycine] is a herbicide used extensively in almost all agricultural and urban areas of the United States and Europe. Although, glyphosate is used widely throughout the world in the production of many crops, it is predominately used in the United States on soybeans, corn, potatoes, and cotton that have been genetically modified to be tolerant to glyphosate. From 1992 to 2007, the agricultural use of glyphosate has increased from less than 10,000 Mg to more than 80,000 Mg, respectively. The greatest areal use is in the midwestern United States where glyphosate is applied on transgenic corn and soybeans. Because of the difficulty and expense in analyzing for glyphosate and AMPA (aminomethylphosphonic acid, a primary glyphosate degradate) in water, there have been only small scale studies on the fate and transport of glyphosate. The characterization of the transport of glyphosate and AMPA on a watershed scale is lacking. Glyphosate and AMPA were frequently detected in the surface waters of 4 agricultural watersheds in studies conducted by the U.S. Geological Survey in the United States and at the Laboratory of Hydrology and Geochemistry of Strasbourg. Two of these basins were located in the midwestern United States where the major crops are corn and soybean, the third is located the lower Mississippi River Basin where the major crops are soybean, corn, rice, and cotton, and the fourth was located near Strasbourg, France where the use of glyphosate was on a vineyard. The load as a percent of use ranged from 0.009 to 0.86 percent and could be related to 3 factors: source strength, hydrology, and flowpath. Glyphosate use in a watershed results in some occurrence in surface water at the part per billion level; however, those 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.

Non Target Site Tolerance Mechanisms Describe Tolerance to Glyphosate in Avena sterilis

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Pablo Tomas Fernandez-Moreno

2016-08-01

Full Text Available 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.

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.

Agricultural non-point source pollution of glyphosate and AMPA at a catchment scale

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Okada, Elena; Perez, Debora; De Geronimo, Eduardo; Aparicio, Virginia; Costa, Jose Luis

2017-04-01

can be attributed to deposition of soil particles that are washed from the field. On the other hand, more than 90 % of the soil samples had glyphosate and AMPA. The highest concentrations were found in the month of June, corresponding to the fallow period were glyphosate is applied as a chemical weed controller in no-till systems. Glyphosate and AMPA detection in groundwater samples was 24% and 35%, respectively. The highest glyphosate levels in groundwater also corresponded to the month of June. Glyphosate occurrence in groundwater was transient, that is, in most of the cases glyphosate was not detected in the subsequent sampling months. The contamination of shallow groundwater (application, that may contribute to groundwater contamination. This is of extreme relevance in the southeast of the Buenos Aires Province, since the main source of drinking water and irrigation is from groundwater resources

EPSPS gene amplification conferring resistance to glyphosate in windmill grass (Chloris truncata) in Australia.

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Ngo, The D; Malone, Jenna M; Boutsalis, Peter; Gill, Gurjeet; Preston, Christopher

2018-05-01

Five glyphosate-resistant populations of Chloris truncata originally collected from New South Wales were compared with one susceptible (S) population from South Australia to confirm glyphosate resistance and elucidate possible mechanisms of resistance. Based on the amounts of glyphosate required to kill 50% of treated plants (LD 50 ), glyphosate resistance (GR) was confirmed in five populations of C. truncata (A536, A528, T27, A534 and A535.1). GR plants were 2.4-8.7-fold more resistant and accumulated less shikimate after glyphosate treatment than S plants. There was no difference in glyphosate absorption and translocation between GR and S plants. The EPSPS gene did not contain any point mutation that had previously been associated with resistance to glyphosate. The resistant plants (A528 and A536) contained up to 32-48 more copies of the EPSPS gene than the susceptible plants. This study has identified EPSPS gene amplification contributing to glyphosate resistance in C. truncata. In addition, a Glu-91-Ala mutation within EPSPS was identified that may contribute to glyphosate resistance in this species. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Pro-106-Ser mutation and EPSPS overexpression acting together simultaneously in glyphosate-resistant goosegrass (Eleusine indica).

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Gherekhloo, Javid; Fernández-Moreno, Pablo T; Alcántara-de la Cruz, Ricardo; Sánchez-González, Eduardo; Cruz-Hipolito, Hugo E; Domínguez-Valenzuela, José A; De Prado, Rafael

2017-07-27

Glyphosate has been used for more than 15 years for weed management in citrus groves in the Gulf of Mexico, at up to 3-4 applications per year. Goosegrass (Eleusine indica (L.) Gaertn.) control has sometimes failed. In this research, the mechanisms governing three goosegrass biotypes (Ein-Or from an orange grove, and Ein-Pl1 and Ein-Pl2 from Persian lime groves) with suspected resistance to glyphosate were characterized and compared to a susceptible biotype (Ein-S). Dose-response and shikimate accumulation assays confirmed resistance of the resistant (R) biotypes. There were no differences in glyphosate absorption, but the R biotypes retained up to 62-78% of the herbicide in the treated leaf at 96 h after treatment (HAT), in comparison to the Ein-S biotype (36%). The 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) activity in the Ein-Or and Ein-S biotypes was over 100-fold lower than the Ein-Pl1 and Ein-Pl2 ones. The latter showed a high EPSPS-basal activity, a mutation at Pro-106-Ser position in the EPSPS gene, and EPSPS overexpression. The EPSPS basal and EPSPS overexpression were positively correlated. The R goosegrass biotypes displayed poor glyphosate translocation. Furthermore, this grassweed showed, for the first time, two mechanisms at the target-site level (Pro-106-Ser mutation + EPSPS overexpression) acting together simultaneously against glyphosate.

Sensibilidade de estirpes de Bradyrhizobium ao glyphosate

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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.

The effect of Saccharomyces cerevisiae on the stability of the herbicide glyphosate during bread leavening.

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Low, F L; Shaw, I C; Gerrard, J A

2005-01-01

To investigate the ability of baker's yeast (Saccharomyces cerevisiae) to degrade the herbicide glyphosate during the fermentation cycle of the breadmaking process. Aqueous glyphosate was added to bread ingredients and kneaded by commercially available breadmaking equipment into dough cultures. Cultures were incubated in the breadmaker throughout the fermentation cycle. The recovery of glyphosate levels following fermentation was determined, thus allowing an estimation of glyphosate degradation by yeast. It was shown, for the first time, that S. cerevisiae plays a role in metabolizing glyphosate during the fermentation stages of breadmaking. Approximately 21% was degraded within 1 h. As a result of projected increases in the glyphosate use on wheat and the role of bread as a dietary staple, this may contribute to more informed decisions being made relating to the use of glyphosate on glyphosate-resistant wheat, from a public health/regulatory perspective.

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...

Corn silage from corn treated with foliar fungicide and performance of Holstein cows.

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Haerr, K J; Lopes, N M; Pereira, M N; Fellows, G M; Cardoso, F C

2015-12-01

Foliar fungicide application to corn plants is used in corn aimed for corn silage in the dairy industry, but questions regarding frequency of application and its effect on corn silage quality and feed conversion when fed to dairy cows remain prevalent. The objective of this study was to evaluate the effects of various foliar fungicide applications to corn on dry matter intake (DMI), milk production, and milk composition when fed to dairy cows. Sixty-four Holstein cows with parity 2.5±1.5, 653±80kg of body weight, and 161±51d in milk were blocked and randomly assigned to 1 of 4 corn silage treatments (total mixed ration with 35% of the dry matter as corn silage). Treatments were as follows: control (CON), corn silage with no applications of foliar fungicide; treatment 1 (1X), corn silage from corn that received 1 application of pyraclostrobin (PYR) foliar fungicide (Headline; BASF Corp.) at corn vegetative stage 5; treatment 2 (2X), corn silage from corn that received the same application as 1X plus another application of a mixture of PYR and metconazole (Headline AMP; BASF Corp.) at corn reproductive stage 1 ("silking"); and treatment 3 (3X), corn silage from corn that received the same applications as 2X as well as a third application of PYR and metconazole at reproductive stage 3 ("milky kernel"). Corn was harvested at about 32% dry matter and 3/4 milk line stage of kernel development and ensiled for 200d. Treatments were fed to cows for 5wk, with the last week being used for statistical inferences. Week -1 was used as a covariate in the statistical analysis. Dry matter intake tended to be lower for cows fed corn silage treated with fungicide than CON (23.8, 23.0, 19.5, and 21.3kg for CON, 1X, 2X, and 3X, respectively). A linear treatment effect for DMI was observed, with DMI decreasing as foliar fungicide applications increased. Treatments CON, 1X, 2X, and 3X did not differ for milk yield (34.5, 34.5, 34.2, and 34.4kg/d, respectively); however, a trend for

WEED CONTROL IN GENETICALLY MODIFIED GLYPHOSATE-TOLERANT SOYBEAN MANEJO DE PLANTAS DANINHAS EM SOJA GENETICAMENTE MODIFICADA TOLERANTE AO GLYPHOSATE

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Júlio Cezar Durigan

2011-04-01

Full Text Available 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. St. Lucia Grass (Brachiaria brizantha ‘Marandu’, forage millet (Pennisetum americanum ‘BN2’, and a treatment with spontaneous growth vegetation were evaluated for plots, and, for subplots, the herbicides glyphosate, chlorimuron - ethyl plus lactofen, and fluazifop-p-butyl, in a sequential spraying, and two controls without any application. Grass cover contributed to the chemical control, suppressing weeds, and the single application of 720 g a.e. ha-1 of glyphosate, independently of the cover crop cultivated in the autumn/winter, was sufficient for adequately controlling Acanthospermum hispidum, Alternanthera tenella, Amaranthus sp., Bidens pilosa, Xanthium strumarium, Cenchrus echinatus, Digitaria sp., and Eleusine indica, with results similar to the treatment (chlorimuron-ethyl + lactofen + fluazifop-p-buthyl. When compared to the weeded control, the herbicides did not affect plants height, dry matter of the aerial parts, mass of 100 grains, and grain yield. Soybean plants grown over St. Lucia Grass and forage millet presented a higher height, however, no other feature was influenced by the cover crop.

KEY-WORDS: Brachiaria brizantha; Pennisetum americanum; no-tillage; Roundup Ready; spontaneous vegetation.

Os sistemas de produção transgênicos, assim como os

Identification and functional analysis of a new glyphosate resistance gene from a fungus cDNA library.

Science.gov (United States)

Tao, Bo; Shao, Bai-Hui; Qiao, Yu-Xin; Wang, Xiao-Qin; Chang, Shu-Jun; Qiu, Li-Juan

2017-08-01

Glyphosate is a widely used broad spectrum herbicide; however, this limits its use once crops are planted. If glyphosate-resistant crops are grown, glyphosate can be used for weed control in crops. While several glyphosate resistance genes are used in commercial glyphosate tolerant crops, there is interest in identifying additional genes for glyphosate tolerance. This research constructed a high-quality cDNA library form the glyphosate-resistant fungus Aspergillus oryzae RIB40 to identify genes that may confer resistance to glyphosate. Using a medium containing glyphosate (120mM), we screened several clones from the library. Based on a nucleotide sequence analysis, we identified a gene of unknown function (GenBank accession number: XM_001826835.2) that encoded a hypothetical 344-amino acid protein. The gene was named MFS40. Its ORF was amplified to construct an expression vector, pGEX-4T-1-MFS40, to express the protein in Escherichia coli BL21. The gene conferred glyphosate tolerance to E. coli ER2799 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

Foliar nitrogen and potassium applications improve photosynthetic activities and water relations in sunflower under moisture deficit condition

International Nuclear Information System (INIS)

Hussain, R.A.; Ahmad, R.

2016-01-01

This study investigated the influence of foliar supplementation of nitrogen (N) potassium (K) and their combination on photosynthetic activities, physiological indices and water relations of two sunflower (Helianthus annuus L.) hybrids Hysen-33 and LG-5551 under water deficit condition. Studies were conducted in a wire-house at Nuclear Institute for Agriculture and Biology, Faisalabad, Pakistan. Treatments were two water stress levels [100 (control) and 60% field capacity (water deficit)], six levels of foliar spray (no spray, water spray, 1% N, 1% K, 0.5% N + 0.5% K and 1% N + 1% K) and each treatment was replicated three times. Results showed that water stress reduced the photosynthetic activities: Pn (photosynthetic rate), E (rate of tanspiration) and gs (stomatal conductance) and water relations i.e., pie w (water potential), pie s (osmotic potential) and pie p (turgor potential) . Soil moisture deficit also significantly reduced the plant height, root length, fresh and dry matter which consequently affected the plant height stress tolerance index (PHSI), root length stress tolerance index (RLSI) and dry matter stress tolerance index (DMSI) in both sunflower hybrids. However, foliar supplementation with N and K or N+K improved the photosynthetic activities, water relations and physiological indices of both the sunflower hybrids. The findings of present study suggest that application of N+K is necessary to have high plant productivity. (author)

Influence of glyphosate in planktonic and biofilm growth of Pseudomonas aeruginosa

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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.

The effect of the herbicide glyphosate on non-target spiders: Part I. Direct effects on Lepthyphantes tenuis under laboratory conditions.

Science.gov (United States)

Haughton, A J; Bell, J R; Wilcox, A; Boatman, N D

2001-11-01

We examined the toxic effects of glyphosate to adult female Lepthyphantes tenuis (Araneae, Linyphiidae), a common spider of agricultural habitats. The overspray technique was used to investigate the effect of the herbicide on forty individuals in each of six glyphosate treatments (2160, 1440, 1080, 720, 360 and 180 g ha-1) and a distilled water control. Spiders collected from the wild were individually placed in exposure chambers and checked every 24 h over a 72-h experimental period. Mortality of L tenuis remained at less than 10% in all treatments at 24 and 48 h after spray application, and only increased marginally (to 13%) after 72 h. These results support other limited data which suggest that glyphosate is 'harmless' to non-target arthropods. More extended laboratory testing to investigate any side-effects of glyphosate on the life history of L tenuis and other non-beneficial invertebrates is required.

Early detection of crop injury from herbicide glyphosate by leaf biochemical parameter inversion

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Early detection of crop injury from 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-Resist...

High permeation rates in liposome systems explain rapid glyphosate biodegradation associated with strong isotope fractionation.

Science.gov (United States)

Ehrl, Benno; Mogusu, Emmanuel O; Kim, Kyoungtea; Hofstetter, Heike; Pedersen, Joel A; Elsner, Martin

2018-05-23

Bacterial uptake of charged organic pollutants such as the widely used herbicide glyphosate is typically attributed to active transporters, whereas passive membrane permeation as an uptake pathway is usually neglected. For 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) liposomes, pH-dependent membrane permeation coefficients (Papp) of glyphosate, determined by nuclear magnetic resonance (NMR) spectroscopy, varied from Papp(pH 7.0) = 3.7 (+/-0.3) × 10-7 m∙s-1 to Papp(pH 4.1) = 4.2 (+/-0.1) × 10-6 m∙s-1. This surprisingly rapid membrane permeation depended on glyphosate speciation and was, at physiological pH, in the range of polar, non-charged molecules suggesting that passive membrane permeation is a potential uptake pathway during glyphosate biodegradation. To test this hypothesis, a Gram-negative glyphosate degrader, Ochrobactrum sp. FrEM, was isolated from glyphosate-treated soil and glyphosate permeation rates inferred from the liposome model were compared to bacterial degradation rates. Estimated maximum permeation rates were, indeed, two orders of magnitudes higher than glyphosate degradation rates. Moreover, biodegradation of millimolar glyphosate concentrations gave rise to pronounced carbon isotope fractionation with an apparent kinetic isotope effect of AKIEcarbon= 1.014 ± 0.003. This value is consistent with unmasked enzymatic isotope fractionation demonstrating that glyphosate biodegradation was little mass transfer-limited and glyphosate exchange across the cell membrane was rapid relative to enzymatic turnover.

Improvement of wheat yield grown under drought stress by boron foliar application at different growth stages

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F.M.F. Abdel-Motagally

2018-04-01

Full Text Available Two field experiments were conducted to determine the effect of boron foliar application and water stress on yield of wheat plant grown in calcareous soil during 2013/2014 and 2014/2015 seasons. The highest mean values obtained against boron application time were potential contributor to total grains mass by improving the plant height (99.42 and 98.32 cm, spike length (11.86 and 11.72 cm, number of spikelets m−2 (332.65 and 324.35, grain yield plant−1 (21.56 and 20.26 g, 1000-grain weight (35.2 and 37.4 g and grain yield (1.87 and 1.85 ton fed.−1, which were recorded at normal irrigation level (100% from the amount of water consumption for wheat with boron spraying at booting stage (B1 in the first and second seasons, respectively. Furthermore, boron application significantly enhanced all studied growth traits under water stress levels (50% from the amount of water consumption for wheat compared to B-untreated plants. Boron spraying at booting stage enhances also plant pigments contents recording its highest mean values under normal water level (100% from the amount of water consumption for wheat. The reduction in stress markers (proline and H2O2 and the enhancement of plant pigments content under water stress levels (50% from the amount of water consumption for wheat by B spraying suggests an alleviating effect of boron foliar application to water stress in the test plant. This alleviating effect was more pronounced when B applied at booting stage. Therefore, booting stage was found to be the best time for boron application to get higher grains production and consequently, better economic returns of wheat. Keywords: Wheat, Growth stages, Boron application time, Water stress, Crop yield, Plant pigments, Proline, H2O2

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

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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.

Alteration of plant physiology by glyphosate and its by-product aminomethylphosphonic acid: an overview.

Science.gov (United States)

Gomes, Marcelo P; Smedbol, Elise; Chalifour, Annie; Hénault-Ethier, Louise; Labrecque, Michel; Lepage, Laurent; Lucotte, Marc; Juneau, Philippe

2014-09-01

It is generally claimed that glyphosate kills undesired plants by affecting the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) enzyme, disturbing the shikimate pathway. However, the mechanisms leading to plant death may also be related to secondary or indirect effects of glyphosate on plant physiology. Moreover, some plants can metabolize glyphosate to aminomethylphosphonic acid (AMPA) or be exposed to AMPA from different environmental matrices. AMPA is a recognized phytotoxin, and its co-occurrence with glyphosate could modify the effects of glyphosate on plant physiology. The present review provides an overall picture of alterations of plant physiology caused by environmental exposure to glyphosate and its metabolite AMPA, and summarizes their effects on several physiological processes. It particularly focuses on photosynthesis, from photochemical events to C assimilation and translocation, as well as oxidative stress. The effects of glyphosate and AMPA on several plant physiological processes have been linked, with the aim of better understanding their phytotoxicity and glyphosate herbicidal effects. © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Comparison between Seed and Foliar Treatment as a Tool in Integrated Pest Management.

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Matyjaszczyk, Ewa

2017-08-02

A study into doses of seed treatments and foliar plant protection products containing an identical active substance registered to control the same pest in the same crops was carried out in the European Union. The results show that, for fungicides, the use of seed treatment is often connected with a significantly lower release of active substance per hectare when compared to foliar treatments. In 11 of 13 cases, the difference was 8-fold or higher. For insecticides, in most of the cases, the consumption of an active substance was several times higher for seed treatment, in one case for foliar application.

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.

Mutations and amplification of EPSPS gene confer resistance to glyphosate in goosegrass (Eleusine indica).

Science.gov (United States)

Chen, Jingchao; Huang, Hongjuan; Zhang, Chaoxian; Wei, Shouhui; Huang, Zhaofeng; Chen, Jinyi; Wang, Xu

2015-10-01

Field-evolved resistance of goosegrass to glyphosate is due to double or single mutation in EPSPS , or amplification of EPSPS leads to increased transcription and protein levels. Glyphosate has been used widely in the south of China. The high selection pressure from glyphosate use has led to the evolution of resistance to glyphosate in weeds. We investigated the molecular mechanisms of three recently discovered glyphosate-resistant Eleusine indica populations (R1, R2 and R3). The results showed that R1 and R2 had double Thr102Ile and Pro106Ser mutation and a single mutation of Pro106Leu in the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene, respectively. Escherichia coli containing the mutated EPSPS genes was tolerant to glyphosate. EPSPS activity in R1 and R2 plants was higher than in the sensitive plants. There was no amino acid substitution in EPSPS gene in R3. However, expression of EPSPS in R3 plants was higher than in glyphosate-susceptible (S) population (13.8-fold) after glyphosate treatment. EPSPS enzyme activity in both R3 and S plants was inhibited by glyphosate, while shikimate accumulation in R3 was significantly lower than for the S population. Further analysis revealed that the genome of R3 contained 28.3-fold more copies of the EPSPS gene than that of susceptible population. EPSPS expression was positively correlated with copy number of EPSPS. In conclusion, mutation of the EPSPS gene and increased EPSPS expression are part of the molecular mechanisms of resistance to glyphosate in Eleusine indica.

Is the growth stimulation by low doses of glyphosate sustained over time?

International Nuclear Information System (INIS)

Cedergreen, Nina

2008-01-01

The herbicide, glyphosate, has been shown to stimulate growth in a range of species when applied at doses of 5-60 g a.e. ha -1 , corresponding to realistic spray drift events. This study investigates growth of shoot parameters over time to detect whether the glyphosate induced growth increase was sustained and had a final effect on reproduction. The results showed that an actual biomass growth rate increase took place within the first week after spraying with glyphosate doses -1 . This initial growth boost kept treated plants larger than untreated plants for up to six weeks, but at harvest there was no significant difference between control plants and treated plants. Possible effects of glyphosate hormesis on the competitive ability of spray drift affected plants are discussed. - Glyphosate induced hormesis in barley is not sustained over time

Is the growth stimulation by low doses of glyphosate sustained over time?

Energy Technology Data Exchange (ETDEWEB)

Cedergreen, Nina [Department of Agricultural Sciences, Faculty of Life Science, University of Copenhagen, Hojbakkegard Alle 13, 2630 Tastrup (Denmark)], E-mail: ncf@life.ku.dk

2008-12-15

The herbicide, glyphosate, has been shown to stimulate growth in a range of species when applied at doses of 5-60 g a.e. ha{sup -1}, corresponding to realistic spray drift events. This study investigates growth of shoot parameters over time to detect whether the glyphosate induced growth increase was sustained and had a final effect on reproduction. The results showed that an actual biomass growth rate increase took place within the first week after spraying with glyphosate doses <60 g a.e. ha{sup -1}. This initial growth boost kept treated plants larger than untreated plants for up to six weeks, but at harvest there was no significant difference between control plants and treated plants. Possible effects of glyphosate hormesis on the competitive ability of spray drift affected plants are discussed. - Glyphosate induced hormesis in barley is not sustained over time.

Adsorption-desorption, mobility and degradation of 14C-Glyphosate in two soil series

International Nuclear Information System (INIS)

Ismail, B. S.; Zaifah Abdul Kadir; Khairiah Jusoh; Nashriyah Mat

2002-01-01

The adsorption desorption and degradation of glyphosate (Roundup) have been studied using 14 C glyphosate in two soils, namely Serdang Series and Sungai Buloh Series. The percentage of adsorption was not significantly different (p 14 C- glyphosate was detected in 0-10 cm zone of the two soils studied. However, in Sungai Buloh Series, a significant amount of 14 C-glyphosate was detected in the 10-20 cm zone. A small amount of 14 C radioactivity was also detected in the leachate of the two soils. The percentage of degradation in the Sungai Buloh and Serdang Series soils was higher at 10 μg/ml and 50 μg/ml, concentration, respectively. At 50 μg/ml concentration the Sungai Buloh Series soil showed higher glyphosate residue (83%) as compared to Serdang Series (48%). In contrast, the glyphosate residue was found to be higher in the Serdang Series (73916) as compared to the Sungai Buloh Series (30%) at 10 μg/ml concentration. (Author)

The Effects of Foliar Application of Urea, Calcium Nitrate and Boric Acid on Growth and Yield of Greenhouse Cucumber (cv. Khassib

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Naser Nasrolahzadehasl

2017-10-01

Full Text Available Introduction: Cucumis sativus L. is one of the most eminent and consuming vegetables which is widely cultivated in the Middle East. Using the controlled and greenhouse cultivation is one of the most appropriate methods to increase production per unit area. In this method, controlling the effective factors of production such as plant nutrition is the important factor to achieve high performance. Besides the accuracy applied in nutritional regulation of plant roots (both in soil and hypothermic environments, in many cases, foliar nutrition is considered by breeder of greenhouse productions. Foliar nutrition is more effective on young leaves, and deficiency of macro and micro nutrients can be removed by this factor. Khassib is one of the most important cultivar of greenhouse cucumber which is widely cultivated in Iran. The present study was conducted to evaluate the effect of foliar application on greenhouse cucumber. Materials and Methods: The experiment was performed on greenhouse cucumber (cv. Khassib for five months (from March 2007 to July 2008 in Ziba Dasht Technical Instruction Center which is located near Karaj, Iran. For this reason the experiment was conducted based on split-split-plot design with three replications. Eight experimental treatments were applied for foliar application including U1C1B1: urea + calcium nitrate +boric acid, U1C1B0: urea + calcium nitrate, U1C0B1: urea + boric acid, U1C0B0: urea, U0C1B1: calcium nitrate + boric acid, U0C1B0: calcium nitrate, U0C0B1: boric acid, U0C0B0: control. The effects of urea, calcium nitrate and boric acid in concentrations 3, 10 and 0.5 (gL-1 respectively on qualitative and quantitative characteristics of greenhouse cucumber, including fruit yield, yield of first class fruit, number of fruits, percentage of first class fruit, fruits T.S.S, plant length, percentage of leaf dry matter, and leaf weight ratio were studied. Results and Discussion: The results showed that calcium nitrate had a

Influence of foliar riboflavin applications to vineyard on grape amino acid content.

Science.gov (United States)

González-Santamaría, Rosario; Ruiz-González, Rubén; Nonell, Santi; Garde-Cerdán, Teresa; Pérez-Álvarez, Eva P

2018-02-01

Nitrogen is an important element for grapevine and winemaking, which affects plant development, grape juice fermentation and has a potential effect in modulating wine quality. The aim was to study the influence of foliar applications of riboflavin (vitamin B2) to vineyard on grape nitrogen composition. This vitamin has a reported capacity to protect different plant species, but its application to favor grape and grape juice quality had not previously been studied. This work reports the oenological properties and the effect on amino acid concentration of grape juices obtained from grapes treated with riboflavin at two different doses compared to control. Results showed that probable alcohol, malic acid, color intensity and hue had significant differences when the riboflavin treatments were applied. Most of the amino acids presented the highest concentrations when the lowest riboflavin dose was used. These results are promising in terms of fermentation development and grape juice nitrogen composition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Foliar Epidermal Studies of Plants in Euphorbiaceae

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H. A. Thakur

2014-03-01

Full Text Available This paper describes foliar epidermal structure in 17 species belonging to 17 genera of the family Euphoprbiaceae. Anomocytic stomata is predominant, rarely they are anisocytic, paracytic on the same foliar surface with different combinations. Leaves are hypostomatic and rarely amphistomatic. The foliar surface is smooth, rarely striated. The foliar epidermal cell walls are straight or undulate. Distribution of stomata, stomatal index, stomatal frequency, stomatal size and other cell wall contours are described in detail.

Glyphosate Shapes a Dinoflagellate-Associated Bacterial Community While Supporting Algal Growth as Sole Phosphorus Source

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Cong Wang

2017-12-01

Full Text Available Glyphosate is a widely used herbicide that can potentially be a phosphorus (P source for phytoplankton and microbes when discharged into the coastal ocean. In contrast to bacteria, few eukaryotic phytoplankton species appear capable of directly utilizing glyphosate. In this study, we observed, after a long delay (>60 days, Prorocentrum donghaiense, a dinoflagellate known to cause major harmful algal blooms in the East China Sea, could grow in a medium with glyphosate as the sole P source; suggesting that P. donghaiense growth was through bacterial mediation. To understand how the bacteria community might respond to glyphosate, we analyzed the 16S rRNA genes of the microbial community present in P. donghaiense cultures when grown under lower (36 μM and higher (360 μM glyphosate concentrations. Based on both Sanger and Illumina high throughput sequencing, we obtained more than 55,323 good-quality sequences, which were classified into six phyla. As the concentration of glyphosate rose, our results showed a significant increase in the phyla Proteobacteria and Firmicutes and a decrease in the phylum Bacteroidetes. Further qPCR (Quantitative PCR analysis showed higher abundances of two specific phylotypes in the higher-glyphosate P. donghaiense cultures when compared to the lower-glyphosate and no-glyphosate cultures. Correspondingly, qPCR displayed the same trend for the abundance of a gammaproteobacterial type of phnJ, a gene encoding Alpha-D-ribose 1-methylphosphonate 5-phosphate C-P lyase, which is responsible for phosphonate degradation. In addition, Tax4Fun analysis based on our 16S rRNA gene sequences results in higher predicted abundances of phosphonate metabolizing genes in glyphosate-treated cultures. This study demonstrates that glyphosate could selectively promote the growth of particular groups of bacteria within an algal culture and in glyphosate enriched coastal waters, this interaction may potentially further facilitate the growth of

Aplicações de fertilizantes foliares na nutrição e na produção do pimentão e do tomateiro Foliar fertilizer applications on nutrition and yield of sweet pepper and tomato

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Hamilton S. Pereira

2002-12-01

Full Text Available Avaliou-se a eficiência de fertilizantes foliares, contendo Ca e B, na nutrição e produção do pimentão cv. Mayata e do tomate cv. Carmem, cultivados em estufas. O delineamento experimental foi de blocos ao acaso com seis tratamentos, três e quatro repetições, respectivamente, para o tomateiro e pimentão. Os tratamentos foram a água de retortagem de xisto (100; 78; 3,0; 12,5; 3,0; 12,5; 4,0 e 0,2 g.L-1 de N, K, S, Ca, Mg, B, Mn e Mo, respectivamente a 0,1; 0,25; 0,5 e 1%; os sais ácido bórico (170 g.kg-1 de B a 0,15% mais cloreto de cálcio a 0,15% e o quelato de cálcio (200 g.kg-1 de Ca a 0,1% e boro orgânico (10 g.kg-1 de B a 0,15%. A aplicação de água de retortagem de xisto a 0,5% via foliar aumentou em 27,4% a produção de frutos de pimentão e os teores foliares de Mg e S em relação à aplicação desse fertilizante a 0,1%. Para o tomateiro, as pulverizações com água de retortagem de xisto a 0,5 e 1% elevaram em 60,5 e 93,8% a produção de frutos em comparação à menor dose desse fertilizante. Os maiores teores de B nas folhas de pimentão e de tomate foram obtidos com as aplicações de sais e resultaram em sintomas visuais de toxicidade de B no início do desenvolvimento das culturas.The efficiency of foliar fertilizers was evaluated on nutrition and yield of sweet pepper cv. Mayata and tomato cv. Carmem, cultivated in plastic greenhouse. For the two experiments the experimental design consisted of randomized blocks with three and four replications for tomato and sweet pepper, respectively, and six treatments (schist retortage water 0.1; 0.25; 0.5 and 1%; boric acid 0.15% plus clorate calcium 0.15% and quelate Ca 0.1% plus organic B 0.15%. The foliar application of schist retortage water 0.5% increased 27.4% the sweet pepper fruit yield and foliar concentrations of Mg and S compared to this fertilizer 0.1%. For tomato, the application of schist retortage water 0.5 and 1% increased 60.5 and 93.8% the fruit yield

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

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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.

Glyphosate-Induced Specific and Widespread Perturbations in the Metabolome of Soil Pseudomonas Species

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Ludmilla Aristilde

2017-06-01

Full Text Available Previous studies have reported adverse effects of glyphosate on crop-beneficial soil bacterial species, including several soil Pseudomonas species. Of particular interest is the elucidation of the metabolic consequences of glyphosate toxicity in these species. Here we investigated the growth and metabolic responses of soil Pseudomonas species grown on succinate, a common root exudate, and glyphosate at different concentrations. We conducted our experiments with one agricultural soil isolate, P. fluorescens RA12, and three model species, P. putida KT2440, P. putida S12, and P. protegens Pf-5. Our results demonstrated both species- and strain-dependent growth responses to glyphosate. Following exposure to a range of glyphosate concentrations (up to 5 mM, the growth rate of both P. protegens Pf-5 and P. fluorescens RA12 remained unchanged whereas the two P. putida strains exhibited from 0 to 100% growth inhibition. We employed a 13C-assisted metabolomics approach using liquid chromatography-mass spectrometry to monitor disruptions in metabolic homeostasis and fluxes. Profiling of the whole-cell metabolome captured deviations in metabolite levels involved in the tricarboxylic acid cycle, ribonucleotide biosynthesis, and protein biosynthesis. Altered metabolite levels specifically in the biosynthetic pathway of aromatic amino acids (AAs, the target of toxicity for glyphosate in plants, implied the same toxicity target in the soil bacterium. Kinetic flux experiments with 13C-labeled succinate revealed that biosynthetic fluxes of the aromatic AAs were not inhibited in P. fluorescens Pf-5 in the presence of low and high glyphosate doses but these fluxes were inhibited by up to 60% in P. putida KT2440, even at sub-lethal glyphosate exposure. Notably, the greatest inhibition was found for the aromatic AA tryptophan, an important precursor to secondary metabolites. When the growth medium was supplemented with aromatic AAs, P. putida S12 exposed to a lethal

Improving growth and yield of cowpea by foliar application of ...

African Journals Online (AJOL)

Water stress impaired cowpea plant growth and decreased ion percentage and chlorophyll and carbohydrate concentration in the shoot as well as yield and its quality. Foliar-applied chitosan, in particular 250 mg/l, increased plant growth, yield and its quality as well as physiological constituents in plant shoot under stressed ...

Importance of Foliar Nitrogen Concentration to Predict Forest Productivity in the Mid-Atlantic Region

Science.gov (United States)

Yude Pan; John Hom; Jennifer Jenkins; Richard Birdsey

2004-01-01

To assess what difference it might make to include spatially defined estimates of foliar nitrogen in the regional application of a forest ecosystem model (PnET-II), we composed model predictions of wood production from extensive ground-based forest inventory analysis data across the Mid-Atlantic region. Spatial variation in foliar N concentration was assigned based on...

Exposure assessment using human biomonitoring for glyphosate and fluroxypyr users in amenity horticulture.

Science.gov (United States)

Connolly, Alison; Jones, Kate; Galea, Karen S; Basinas, Ioannis; Kenny, Laura; McGowan, Padraic; Coggins, Marie

2017-08-01

Pesticides and their potential adverse health effects are of great concern and there is a dearth of knowledge regarding occupational exposure to pesticides among amenity horticulturalists. This study aims to measure occupational exposures to amenity horticuturalists using pesticides containing the active ingredients, glyphosate and fluroxypyr by urinary biomonitoring. A total of 40 work tasks involving glyphosate and fluroxypyr were surveyed over the period of June - October 2015. Workers used a variety of pesticide application methods; manual knapsack sprayers, controlled droplet applicators, pressurised lance applicators and boom sprayers. Pesticide concentrations were measured in urine samples collected pre and post work tasks using liquid chromatography tandem mass spectrometry (LC-MS/MS). Differences in pesticide urinary concentrations pre and post work task, and across applications methods were analysed using paired t-tests and linear regression. Pesticide urinary concentrations were higher than those reported for environmental exposures and comparable to those reported in some agricultural studies. Log-transformed pesticide concentrations were statistically significantly higher in post-work samples compared to those in pre-work samples (paired t-test, p<0.001; for both μgL -1 and μmol/mol creatinine). Urinary pesticide concentrations in post-work samples had a geometric mean (geometric standard deviation) of 0.66 (1.11) μgL -1 for glyphosate and 0.29 (1.69) μgL -1 for fluroxypyr. Linear regression revealed a statistically significant positive association to exist between the time-interval between samples and the log-transformed adjusted (i.e. post- minus pre-task) pesticide urinary concentrations (β=0.0039; p<0.0001). Amenity horticulturists can be exposed to pesticides during tasks involving these products. Further research is required to evaluate routes of exposure among this occupational group. Crown Copyright © 2017. Published by Elsevier GmbH. All

Glyphosate Accumulation and Detrimental Effects on Coffea Arabica

DEFF Research Database (Denmark)

Schrübbers, Lars Christoph

and the MS/MS system provided a limit of quantification (LOQ) below 0.1 mg/kg; the commonly used maximum residue limit (MRL) for glyphosate in plant derived food products. Glyphosate was found in all samples analyzed from different coffee fields, regardless of management practices. AMPA was not detected......Coffee is one of the most popular beverages worldwide and a highly traded commodity. In order to maintain a high yield of the perennial crop, weed competition for resources needs to be reduced. For this purpose herbicides are commonly applied, with glyphosate being one of the most prominent...

Glyphosate: useful, dangerous? To license or to phase out?

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Karl Ernst v. Mühlendahl, Matthias Otto

2016-12-01

Full Text Available Glyphosate, a herbicide blocking an enzyme essential for all plants, but not for animals and humans, has certain advantages as compared to other plant protection products. It is not persistent. Due to the production and application of more than 700.000 tons per year, large portions of mankind are exposed. The International Agency on Research on Cancer (IARC of the World Health Organisation (WHO has looked more closely on glyphosate and has classified it as “probably carcinogenic for humans (2A” The German Bundesamt für Risikobewertung (BfR and the European Food Safety Authority (EFSA have analysed the data and contradict the IARC classification. In this paper, the process of decision finding and essential arguments for the contradictory classification are commented. In the ensuing public discussions, conflicts could have been rationalized if the BfR and the EFSA had offered more transparency regarding their evaluation and had restricted their opinions and their proposals to their genuine task: to propose regulations concerning the risks (which follow from possible hazards.

Effects of glyphosate herbicide on the gastrointestinal microflora of Hawaiian green turtles (Chelonia mydas) Linnaeus.

Science.gov (United States)

Kittle, Ronald P; McDermid, Karla J; Muehlstein, Lisa; Balazs, George H

2018-02-01

In Hawaii, glyphosate-based herbicides frequently sprayed near shorelines may be affecting non-target marine species. Glyphosate inhibits aromatic amino acid biosynthesis (shikimate pathway), and is toxic to beneficial gut bacteria in cattle and chickens. Effects of glyphosate on gut bacteria in marine herbivorous turtles were assessed in vitro. When cultures of mixed bacterial communities from gastrointestinal tracts of freshly euthanized green turtles (Chelonia mydas), were exposed for 24h to six glyphosate concentrations (plus deionized water control), bacterial density was significantly lower at glyphosate concentrations≥2.2×10 -4 gL -1 (absorbance measured at 600nm wavelength). Using a modified Kirby-Bauer disk diffusion assay, the growth of four bacterial isolates (Pantoea, Proteus, Shigella, and Staphylococcus) was significantly inhibited by glyphosate concentrations≥1.76×10 -3 gL -1 . Reduced growth or lower survival of gut bacteria in green turtles exposed to glyphosate could have adverse effects on turtle digestion and overall health. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fate of the herbicides glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron in two Finnish arable soils.

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Laitinen, Pirkko; Siimes, Katri; Eronen, Liisa; Rämö, Sari; Welling, Leena; Oinonen, Seija; Mattsoff, Leona; Ruohonen-Lehto, Marja

2006-06-01

The fate of five herbicides (glyphosate, glufosinate-ammonium, phenmedipham, ethofumesate and metamitron) was studied in two Finnish sugar beet fields for 26 months. Soil types were sandy loam and clay. Two different herbicide-tolerant sugar beet cultivars and three different herbicide application schedules were used. Meteorological data were collected throughout the study and soil properties were thoroughly analysed. An extensive data set of herbicide residue concentrations in soil was collected. Five different soil depths were sampled. The study was carried out using common Finnish agricultural practices and represents typical sugar beet cultivation conditions in Finland. The overall observed order of persistence was ethofumesate > glyphosate > phenmedipham > metamitron > glufosinate-ammonium. Only ethofumesate and glyphosate persisted until the subsequent spring. Seasonal variation in herbicide dissipation was very high and dissipation ceased almost completely during winter. During the 2 year experiment no indication of potential groundwater pollution risk was obtained, but herbicides may cause surface water pollution. Copyright (c) 2006 Society of Chemical Industry

Foliar phosphite application has minor phytotoxic impacts across a diverse range of conifers and woody angiosperms.

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Scott, Peter; Bader, Martin Karl-Friedrich; Williams, Nari Michelle

2016-10-01

Phytophthora plant pathogens cause tremendous damage in planted and natural systems worldwide. Phosphite is one of the only effective chemicals to control broad-scale Phytophthora disease. Little work has been done on the phytotoxic effects of phosphite application on plant communities especially in combination with plant physiological impacts. Here, we tested the phytotoxic impact of phosphite applied as foliar spray at 0, 12, 24 and 48 kg a.i. ha(-1) . Eighteen-month-old saplings of 13 conifer and angiosperm species native to New Zealand, and two exotic coniferous species were treated and the development of necrotic tissue and chlorophyll-a-fluorescence parameters (optimal quantum yield, Fv /Fm ; effective quantum yield of photosystem II, ΦPSII ) were assessed. In addition, stomatal conductance (gs ) was measured on a subset of six species. Significant necrosis assessed by digital image analysis occurred in only three species: in the lauraceous canopy tree Beilschmiedia tawa (8-14%) and the understory shrub Dodonaea viscosa (5-7%) across phosphite concentrations and solely at the highest concentration in the myrtaceous pioneer shrub Leptospermum scoparium (66%). In non-necrotic tissue, Fv /Fm , ΦPSII and gs remained unaffected by the phosphite treatment. Overall, our findings suggest minor phytotoxic effects resulting from foliar phosphite application across diverse taxa and regardless of concentration. This study supports the large-scale use of phosphite as a management tool to control plant diseases caused by Phytophthora pathogens in plantations and natural ecosystems. Long-term studies are required to ascertain potential ecological impacts of repeated phosphite applications. © 2016 Scandinavian Plant Physiology Society.

Non-point source pollution of glyphosate and AMPA in a rural basin from the southeast Pampas, Argentina.

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Okada, Elena; Pérez, Débora; De Gerónimo, Eduardo; Aparicio, Virginia; Massone, Héctor; Costa, José Luis

2018-05-01

We measured the occurrence and seasonal variations of glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in different environmental compartments within the limits of an agricultural basin. This topic is of high relevance since glyphosate is the most applied pesticide in agricultural systems worldwide. We were able to quantify the seasonal variations of glyphosate that result mainly from endo-drift inputs, that is, from direct spraying either onto genetically modified (GM) crops (i.e., soybean and maize) or onto weeds in no-till practices. We found that both glyphosate and AMPA accumulate in soil, but the metabolite accumulates to a greater extent due to its higher persistence. Knowing that glyphosate and AMPA were present in soils (> 93% of detection for both compounds), we aimed to study the dispersion to other environmental compartments (surface water, stream sediments, and groundwater), in order to establish the degree of non-point source pollution. Also, we assessed the relationship between the water-table depth and glyphosate and AMPA levels in groundwater. All of the studied compartments had variable levels of glyphosate and AMPA. The highest frequency of detections was found in the stream sediments samples (glyphosate 95%, AMPA 100%), followed by surface water (glyphosate 28%, AMPA 50%) and then groundwater (glyphosate 24%, AMPA 33%). Despite glyphosate being considered a molecule with low vertical mobility in soils, we found that its detection in groundwater was strongly associated with the month where glyphosate concentration in soil was the highest. However, we did not find a direct relation between groundwater table depth and glyphosate or AMPA detections. This is the first simultaneous study of glyphosate and AMPA seasonal variations in soil, groundwater, surface water, and sediments within a rural basin.

Possible effects of glyphosate on Mucorales abundance in the rumen of dairy cows in Germany.

Science.gov (United States)

Schrödl, Wieland; Krüger, Susanne; Konstantinova-Müller, Theodora; Shehata, Awad A; Rulff, Ramon; Krüger, Monika

2014-12-01

Glyphosate (N-phosphonomethyl glycine) is registered as a herbicide for many food and non-food crops, as well as non-crop areas where total vegetation control is desired. Glyphosate influences the soil mycobiota; however, the possible effect of glyphosate residues in animal feed (soybean, corn, etc.) on animal mycobiota is almost unknown. Accordingly, the present study was initiated to investigate the mycological characteristics of dairy cows in relationship to glyphosate concentrations in urine. A total of 258 dairy cows on 14 dairy farms in Germany were examined. Glyphosate was detected in urine using ELISA. The fungal profile was analyzed in rumen fluid samples using conventional microbiological culture techniques and differentiated by MALDI-TOF mass spectrometry. LPS-binding protein (LBP) and antibodies (IgG1, IgG2, IgA, and IgM) against fungi were determined in blood using ELISA. Different populations of Lichtheimia corymbifera, Lichtheimia ramosa, Mucor, and Rhizopus were detected. L. corymbifera and L. ramosa were significantly more abundant in animals containing high glyphosate (>40 ng/ml) concentrations in urine. There were no significant changes in IgG1 and IgG2 antibodies toward isolated fungi that were related to glyphosate concentration in urine; however, IgA antibodies against L. corymbifera and L. ramosa were significantly lower in the higher glyphosate groups. Moreover, a negative correlation between IgM antibodies against L. corymbifera, L. ramosa, and Rhizopus relative to glyphosate concentration in urine was observed. LBP also was significantly decreased in animals with higher concentrations of glyphosate in their urine. In conclusion, glyphosate appears to modulate the fungal community. The reduction of IgM antibodies and LBP indicates an influence on the innate immune system of animals.

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

Does foliar application of salicylic acid protects nitrate reductase and ...

African Journals Online (AJOL)

The present study was conducted to assess whether exogenous applied salicylic acid (SA) as a foliar spray could ameliorate the adverse effects of virus infection in two maize cultivars (maize cv. sabaini and maize cv. Nab El-gamal). The plants were grown under normal field conditions for two weeks in sand clay soil, and ...

Clastogenic Effects of Glyphosate in Bone Marrow Cells of Swiss Albino Mice

International Nuclear Information System (INIS)

Prasad, S.; Srivastava, S.; Singh, M.; Shukla, Y.

2009-01-01

Glyphosate (N-(phosphonomethyl) glycine, C 3 H 8 NO 5 P), a herbicide, used to control unwanted annual and perennial plants all over the world. Nevertheless, occupational and environmental exposure to pesticides can pose a threat to nontarget species including human beings. Therefore, in the present study, genotoxic effects of the herbicide glyphosate were analyzed by measuring chromosomal aberrations (CAs) and micronuclei (MN) in bone marrow cells of Swiss albino mice. A single dose of glyphosate was given intraperitoneally (i.p) to the animals at a concentration of 25 and 50 mg/kg b.wt. Animals of positive control group were injected i.p. benzo(a)pyrene (100 mg/kg b.wt., once only), whereas, animals of control (vehicle) group were injected i.p. dimethyl sulfoxide (0.2 mL). Animals from all the groups were sacrificed at sampling times of 24, 48, and 72 hours and their bone marrow was analyzed for cytogenetic and chromosomal damage. Glyphosate treatment significantly increases CAs and MN induction at both treatments and time compared with the vehicle control (P<.05). The cytotoxic effects of glyphosate were also evident, as observed by significant decrease in mitotic index (MI). The present results indicate that glyphosate is clastogenic and cytotoxic to mouse bone marrow.

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.

Effects of spray drift of glyphosate on nontarget terrestrial plants-A critical review.

Science.gov (United States)

Cederlund, Harald

2017-11-01

Glyphosate is a widely used broad-spectrum postemergent herbicide used for weed control in both agricultural and nonagricultural settings. Spray drift of glyphosate can pose a risk to nontarget terrestrial plants and plant communities outside the intended area of application, but the lack of a well-established predicted-no-effect drift rate makes properly assessing such risk difficult. For this reason, a literature review and meta-analysis was carried out with the aim to determine the level of drift that is likely to cause harm to plants and to explore what spray-reducing targets would be sufficiently protective. No-observed-adverse effect rates, lowest-observed-adverse effect rates, and effect rates giving 10, 25, and 50% effects were extracted from a total of 39 different publications. The data were combined per species, and species sensitivity distributions were constructed and fitted with a log-logistic model to assess protectiveness. No systematic differences were detected between the responses of monocotyledons or dicotyledons, but wild plants were found to be generally less sensitive to glyphosate drift than domesticated plants. The results indicate that restricting spray drift to a level below 5 g a.e./ha would protect approximately 95% of all higher plant species against minor adverse effects of glyphosate drift and that rates below 1 to 2 g a.e./ha would be almost completely protective. No studies were encountered that evaluated effects of spray drift against nonvascular plants, and therefore, the conclusions are only valid for vascular plants. Environ Toxicol Chem 2017;36:2879-2886. © 2017 SETAC. © 2017 SETAC.

Physiological responses to glyphosate are dependent on Eucalyptus urograndis genotype

Science.gov (United States)

Two experiments were conducted to evaluate the response of Eucalyptus urograndis genotypes (C219 and GG100) to glyphosate in growth chambers. As glyphosate dose increased (18 up to 720 g ae ha-1), CO2 assimilation rate, transpiration rate, and stomatal conductance decreased fastest and strongest in ...

Weed infestation of a winter wheat canopy under the conditions of application of different herbicide doses and foliar fertilization

Directory of Open Access Journals (Sweden)

Piotr Kraska

2012-12-01

Full Text Available The present study was carried out in the years 2006-2008 in the Bezek Experimental Farm (University of Life Sciences in Lublin. A two-factor field experiment was set up according to a randomized block design, in three replications. The experimental field was situated on medium heavy mixed rendzina developed from chalk rock with medium dusty loam granulometric composition. The soil was characterised by neutral pH, a very high content of P (342.1 and K (278.9 along with a very low level of magnesium (16.0 mg × kg-1 of soil and organic carbon (over 3.5%. The aim of this research was to compare the effect of three herbicide doses and two foliar fertilizers applied in a winter wheat canopy on weed infestation. The herbicides Mustang 306 SE 0.4 l × ha-1 and Attribut 70 WG 60 g × ha-1 were applied at full recommended doses as well as at doses reduced to 75% and 50%. Foliar fertilizers Insol 3 (1 1 × ha-1 and FoliCare (20 kg × ha-1 were applied at full recommended doses twice in the growing season BBCH* development stage 23-25* and 33-35*. The control was not treated with the herbicides and foliar fertilizers. The weed infestation level was determined by means of the quantitative gravimetric method at two dates: the first one 6 weeks after herbicide application and the second one - before harvest. The number of weed individuals was counted; species composition and air-dry biomass of aboveground parts were estimated from randomly selected areas of 1 m × 0.25 m at four sites on each plot. Galium aparine and Apera spica-venti plants were sampled for molecular analysis 6 weeks after herbicide application (the treatments with the full herbicide dose, a 50% dose and the control without herbicides. The density of weeds and weed air-dry weight were statistically analysed by means of variance analysis, and the mean values were estimated with Tukey's confidence intervals (p=0.05. It was found that the number of weeds and air-dry weight of weeds in the

Effects of interactions between Collembola and soil microbial community on the degradation of glyphosate-based herbicide

Science.gov (United States)

Wee, J.; Lee, Y. S.; Son, J.; Kim, Y.; Nam, T. H.; Cho, K.

2017-12-01

Glyphosate is the most widely used herbicide because of its broad spectrum activity and effectiveness, however, little is known about adverse effects on non-target species and their interactions. Therefore, in this study, we investigated the effects of glyphosate on interactions between Collembola and soil microbial community and the effect of Collembola on degradation of glyphosate. The experiment carried out in PS container filled with 30g of soil according to OECD 232 guidelines. Investigating the effects of soil microbial community and Collembola on degradation of glyphosate, we prepared defaunated field soil (only maintaining soil microbial community, sampling in May and September, 2016.) and autoclaved soil with 0, 10, 30 adults of Paronychiurus kimi (Collembola) respectively. Survived adults and hatched juveniles of P. kimi were counted after 28-day exposures in both soils spiked with 100 mg/kg of glyphosate. Glyphosate in soil of 7, 14, 21, 28 days after spiking of glyphosate based herbicide was analyzed by spectrophotometer (Jan et al., 2009). Also soil microbial community structure was investigated using phospholipid fatty acids (PLFAs) composition analysis of soils following the procedures given by the Sherlock Microbial Identification System (MIDI Inc., Newark, DE). Glyphosate (100mg/kg soil) has no effects on reproduction and survival of P. kimi in any soils. Also, glyphosate in soils with Collembola was more rapidly degraded. Rapid increase of soil microbial biomass(PLFAs) was shown in soil with Collembola addition. This result showed that glyphosate affected interactions between Collembola and soil microorganisms, and also soil microbial community affected by Collembola changed degradation of glyphosate.

Effects of Foliar Applications of Sulfur, Nitrogen and Phosphorus on Castor Bean (Ricinus cmmunis L. Seed Yield and its Components under Water Deficit Conditions

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M. Mosavi

2015-08-01

Full Text Available To determine the effects of foliar applications of some macroelements on castor seed yield and its components under drought stress conditions, an experiment was conducted at the Agricultural Research Center of East Azerbaijan province. A factorial experiment, based on randomized complete block design with three replications, was carried out during 2013 growing season. Treatment factors consisted of irrigations with two levels (no water deficit and water deficit during grain filling stage and of foliar applications of macroelements with four levels [control, wettable sulfur (0.2 percent, nitrogen (urea: 0.6 percent and phosphor (super phosphate triple: 0.4 percent. Traits studied were: plant height, number of inflorescence, number of lateral branches, number of leaves, leaf temperature, relative water content, number of seeds per plant, 1000-kernal weight and seed yield. All traits, except number of inflorescence, were affected significantly by drought stress. Water deficit reduced plant height, number of leaves, number of seeds per plant, 1000-kernal weight, seed yield, relative water content, while it increased leaf temperature. Number of lateral branches was affected significantly by interaction between factors. Maximum latral branches (1.86 were obtained under non-stress treatment with nitrogen foliar application. Moderate drought stress had significant effect on leaf temperature and relative water content. It seems that, these traits can be used in determination of water deficit effects on castor bean.

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...

Foliar Absorption, Translocation and Utilization of Zn-65 by Mango Seedlings

International Nuclear Information System (INIS)

Mohamed, F.A.; Sharaf, A.N.M.; Awad, S.M.; Abu EL Azm, S.K.

2001-01-01

Greenhouse experiment was designed using ZnSO 4 at rates of 0.125,0.25 and 0.50%. Solutions were adjusted to ph 6.0 and Tween-20 was added as a surfactant. The prepared solutions were labelled with carrier-free Zn-65. Six-month old mango seedlings were arranged in a complete block design to study the foliar absorption,translocation and percentage use of Zn-65 as influenced by soil application of phosphorus. The total absorption of Zn-65 by mango leaves was affected by spraying treatment of Zn-65 and soil application of phosphorus. In this respect increasing the rates of labelled Zn solution resulted in a great increment in the total absorption of in total absorption of Zn-65 by mango leaves was observed due to increasing P rates as a soil application from 0.0 up to 100 ppm. Translocation of the absorbed Zn-65 either in upward or downward direction was positively related to the absorbed amount. The percentage use of Zn-65 by mango leaves was reduced by increasing foliar Zn rates. On the contrary, it was slightly increased as a result of increasing soil application rate of P. Generally, the percentage use of Zn-65 mango leaves was ranged between 8.7 and 16.87 under the conditions of this experiment. Therefore, foliar application of ZnSO 4 could be recommended as a good source of Zn for mango nutrition in particular with addition of high rates of phosphorus as a soil application

Epidemiologic studies of glyphosate and non-cancer health outcomes: a review.

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Mink, Pamela J; Mandel, Jack S; Lundin, Jessica I; Sceurman, Bonnielin K

2011-11-01

The United States (US) Environmental Protection Agency (EPA) and other regulatory agencies around the world have registered glyphosate as a broad-spectrum herbicide for use on multiple food and non-food use crops. To examine potential health risks in humans, we searched and reviewed the literature to evaluate whether exposure to glyphosate is associated causally with non-cancer health risks in humans. We also reviewed biomonitoring studies of glyphosate to allow for a more comprehensive discussion of issues related to exposure assessment and misclassification. Cohort, case-control and cross-sectional studies on glyphosate and non-cancer outcomes evaluated a variety of endpoints, including non-cancer respiratory conditions, diabetes, myocardial infarction, reproductive and developmental outcomes, rheumatoid arthritis, thyroid disease, and Parkinson's disease. Our review found no evidence of a consistent pattern of positive associations indicating a causal relationship between any disease and exposure to glyphosate. Most reported associations were weak and not significantly different from 1.0. Because accurate exposure measurement is crucial for valid results, it is recommended that pesticide-specific exposure algorithms be developed and validated. Copyright © 2011 Elsevier Inc. All rights reserved.

The need for independent research on the health effects of glyphosate-based herbicides.

Science.gov (United States)

Landrigan, Philip J; Belpoggi, Fiorella

2018-05-29

Glyphosate, formulated as Roundup, is the world's most widely used herbicide. Glyphosate is used extensively on genetically modified (GM) food crops designed to tolerate the herbicide, and global use is increasing rapidly. Two recent reviews of glyphosate's health hazards report conflicting results. An independent review by the International Agency for Research on Cancer (IARC) found that glyphosate is a "probable human carcinogen". A review by the European Food Safety Agency (EFSA) found no evidence of carcinogenic hazard. These differing findings have produced regulatory uncertainty. Reflecting this regulatory uncertainty, the European Commission on November 27 2017, extended authorization for glyphosate for another 5 years, while the European Parliament opposed this decision and issued a call that pesticide approvals be based on peer-reviewed studies by independent scientists rather than on the current system that relies on proprietary industry studies. The Ramazzini Institute has initiated a pilot study of glyphosate's health hazards that will be followed by an integrated experimental research project. This evaluation will be independent of industry support and entirely sponsored by worldwide crowdfunding. The aim of the Ramazzini Institute project is to explore comprehensively the effects of exposures to glyphosate-based herbicides at current real-world levels on several toxicological endpoints, including carcinogenicity, long-term toxicity, neurotoxicity, endocrine disrupting effects, prenatal developmental toxicity, the microbiome and multi-generational effects.

Glyphosate (Ab)sorption by Shoots and Rhizomes of Native versus Hybrid Cattail (Typha).

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Zheng, Tianye; Sutton, Nora B; de Jager, Pim; Grosshans, Richard; Munira, Sirajum; Farenhorst, Annemieke

2017-11-01

Wetlands in the Prairie Pothole Region of North America are integrated with farmland and contain mixtures of herbicide contaminants. Passive nonfacilitated diffusion is how most herbicides can move across plant membranes, making this perhaps an important process by which herbicide contaminants are absorbed by wetland vegetation. Prairie wetlands are dominated by native cattail (Typha latifolia) and hybrid cattail (Typha x glauca). The objective of this batch equilibrium study was to compare glyphosate absorption by the shoots and rhizomes of native versus hybrid cattails. Although it has been previously reported for some pesticides that passive diffusion is greater for rhizome than shoot components, this is the first study to demonstrate that the absorption capacity of rhizomes is species dependent, with the glyphosate absorption being significantly greater for rhizomes than shoots in case of native cattails, but with no significant differences in glyphosate absorption between rhizomes and shoots in case of hybrid cattails. Most importantly, glyphosate absorption by native rhizomes far exceeded that of the absorption occurring for hybrid rhizomes, native shoots and hybrid shoots. Glyphosate has long been used to manage invasive hybrid cattails in wetlands in North America, but hybrid cattail expansions continue to occur. Since our results showed limited glyphosate absorption by hybrid shoots and rhizomes, this lack of sorption may partially explain the poorer ability of glyphosate to control hybrid cattails in wetlands.

Ex Vivo Application of Secreted Metabolites Produced by Soil-Inhabiting Bacillus spp. Efficiently Controls Foliar Diseases Caused by Alternaria spp.

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Ali, Gul Shad; El-Sayed, Ashraf S A; Patel, Jaimin S; Green, Kari B; Ali, Mohammad; Brennan, Mary; Norman, David

2016-01-15

Bacterial biological control agents (BCAs) are largely used as live products to control plant pathogens. However, due to variable environmental and ecological factors, live BCAs usually fail to produce desirable results against foliar pathogens. In this study, we investigated the potential of cell-free culture filtrates of 12 different bacterial BCAs isolated from flower beds for controlling foliar diseases caused by Alternaria spp. In vitro studies showed that culture filtrates from two isolates belonging to Bacillus subtilis and Bacillus amyloliquefaciens displayed strong efficacy and potencies against Alternaria spp. The antimicrobial activity of the culture filtrate of these two biological control agents was effective over a wider range of pH (3.0 to 9.0) and was not affected by autoclaving or proteolysis. Comparative liquid chromatography-mass spectrometry (LC-MS) analyses showed that a complex mixture of cyclic lipopeptides, primarily of the fengycin A and fengycin B families, was significantly higher in these two BCAs than inactive Bacillus spp. Interaction studies with mixtures of culture filtrates of these two species revealed additive activity, suggesting that they produce similar products, which was confirmed by LC-tandem MS analyses. In in planta pre- and postinoculation trials, foliar application of culture filtrates of B. subtilis reduced lesion sizes and lesion frequencies caused by Alternaria alternata by 68 to 81%. Taken together, our studies suggest that instead of live bacteria, culture filtrates of B. subtilis and B. amyloliquefaciens can be applied either individually or in combination for controlling foliar diseases caused by Alternaria species. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Glyphosate contaminated soil remediation by atmospheric pressure dielectric barrier discharge plasma and its residual toxicity evaluation.

Science.gov (United States)

Wang, Tiecheng; Ren, Jingyu; Qu, Guangzhou; Liang, Dongli; Hu, Shibin

2016-12-15

Glyphosate was one of the most widely used herbicides in the world. Remediation of glyphosate-contaminated soil was conducted using atmospheric pressure dielectric barrier discharge (DBD) plasma. The feasibility of glyphosate degradation in soil was explored, and the soil leachate toxicity after remediation was assessed via a seed germination test. The experimental results showed that approximately 93.9% of glyphosate was degraded within 45min of DBD plasma treatment with an energy yield of 0.47gkWh -1 , and the degradation process fitted the first-order kinetic model. Increasing the discharge voltage and decreasing the organic matter content of the soil were both found to facilitate glyphosate degradation. There existed appropriate soil moisture to realize high glyphosate degradation efficiency. Glyphosate mineralization was confirmed by changes of total organic carbon (TOC), chemical oxygen demand (COD), PO 4 3- and NO 3 - . The degradation intermediates including glycine, aminomethylphosphonic acid, acetic acid, formic acid, PO 4 3- and NO 3 - , CO 2 and CO were observed. A possible pathway for glyphosate degradation in the soil using this system was proposed. Based on the soil leachate toxicity test using wheat seed germination, the soil did not exhibit any hazardous effects following high-efficiency glyphosate degradation. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of foliar application of inactivated yeast on the phenolic composition of Vitis vinifera L. cv. Agiorgitiko grapes under different irrigation levels

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Kogkou C

2017-05-01

Full Text Available Charikleia Kogkou,1 Evangelia Chorti,2 Maria Kyraleou,1 Stamatina Kallithraka,1 Stefanos Koundouras,3 Gerard Logan,1 Ioannis Kanakis,4 Yorgos Kotseridis1 1Laboratory of Enology, Department of Food Science and Technology, Agricultural University of Athens, Athens, Greece; 2Cooperative Winery of Nemea, Nemea, Greece; 3Laboratory of Viticulture, School of Agriculture, Aristotle University of Thessaloniki, Thessaloniki, Greece; 4Fassoulis Grapevine Nurseries, Nemea, Greece Abstract: Recent climate changes have caused the rising of average growing season temperatures leading to the advancement of vine phenological stages and to earlier harvests. This could result in the production of grapes with advanced berry sugar accumulation, but incomplete phenolic ripeness, thereby jeopardizing wine quality. This study aims to evaluate the effects of the application of a new product consisting of yeast derivatives on the phenolic maturity and composition of Agiorgitiko grapes and wines, under contrasting water conditions. The experiment was arranged as a 2×2 factorial design in a commercial vineyard situated in southern Greece, combining foliar spraying with LalVigne® Mature (two applications after veraison and an untreated control and water conditions (deficit irrigation and nonirrigated. Irrigation accelerated berry sugar accumulation, increased berry weight and anthocyanin content, and decreased skin tannin concentration. Spraying with yeast derivatives did not affect phenolic content of berry components, and it had no effect on must attributes. Foliar application of yeast derivatives resulted in a higher phenolic potential of the produced wines, only when combined with irrigation. Keywords: foliar spray, deficit irrigation, phenolic maturity, anthocyanins, tannins

Effects of glyphosate-based herbicides on survival, development and growth of invasive snail (Pomacea canaliculata).

Science.gov (United States)

Xu, Yanggui; Li, Adela Jing; Li, Kaibin; Qin, Junhao; Li, Huashou

2017-12-01

This study tests the hypotheses that whether environmental relevance of glyphosate would help control spread of the invasive snail Pomacea canaliculata, or benefit its population growth worldwide. Our results showed that glyphosate induced acute toxicity to the snail only at high concentrations (96h LC50 at 175mg/L) unlikely to occur in the environment. Long-term exposures to glyphosate at sublethal levels (20 and 120mg/L) caused inhibition of food intake, limitation of growth performance and alterations in metabolic profiles of the snail. It is worth noting that glyphosate at 2mg/L benefited growth performance in P. canaliculata. Chronic exposures of glyphosate significantly enhanced overall metabolic rate and altered catabolism from protein to carbohydrate/lipid mode. Cellular responses in enzyme activities showed that the exposed snails could increase tolerance by their defense system against glyphosate-induced oxidative stress, and adjustment of metabolism to mitigate energy crisis. Our study displayed that sublethal concentrations of glyphosate might be helpful in control of the invasive species by food intake, growth performance and metabolic interruption; whether environmental relevance of glyphosate (≤2mg/L) benefits population growth of P. canaliculata is still inconclusive, which requires further field study. Copyright © 2017 Elsevier B.V. All rights reserved.

The intensity of non-target site mechanisms influences the level of resistance of sourgrass to glyphosate

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Flávia Regina da Costa

2014-02-01

Full Text Available 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 pattern of absorption was observed between S (susceptible and R2 from 12 up to 48 hours after treatment with glyphosate (HAT, and between S and R1 just at 12 HAT. The initial difference in glyphosate absorption among the biotypes did not maintained at 96 HAT and afterwards. Smaller amount of herbicide left the treated leaf into the rest of shoot and roots in R2 (25% than in S (58% and R1 (52%. In addition, slight difference in glyphosate translocation was observed between S and R1. We found high percentage (81% of glyphosate in the S biotype up to 168 HAT, while just 44% and 2% of glyphosate was recovered from R1 and R2 plant tissues. In addition, high percentage of glyphosate metabolites was found in R2 (98% and R1 (56% biotypes, while a very low percentage (11% was found in the S biotype. As previous studies indicated resistant factors of 3.5 and 5.6 for R1 and R2, respectively, we conclude that the differential response of sourgrass biotypes is derived from the intensity of the non-target site mechanisms involved in the resistance to glyphosate.

Foliar-applied urea modulates nitric oxide synthesis metabolism and glycinebetaine accumulation in drought-stressed maize

International Nuclear Information System (INIS)

Zhang, L.; Tian, L.; Lai, J.; Zheng, P.; Liang, Z.; Alva, A

2014-01-01

Foliar urea has been proved to play a better positive role in enhancing accumulation of nitric oxide (NO) and glycinebetaine (GB) in maize (Zea mays L.) under drought stress (DS). However, it is unclear how foliar urea affects biosynthetic metabolism of NO and its relationship with GB accumulation. This study was on investigating the effect of foliar- applied urea on seedlings of maize cultivar Zhengdan 958 grown in a hydroponic medium under DS or No DS. Contents of NO and GB and nitric oxide synthase (NOS) activity increased and peaked 12 h after the treatment. Nitrate reductase activity (NRA) followed the similar pattern 6h after the treatment. Under DS foliar urea application increased NR and NOS activity and, thereby, increased NO formation. Therefore, enhancement in activities of both NRA and NOS resulted in an increase of NO accumulation. Foliar- applied urea could induce an increased NO burst by enhanced NO synthesis metabolism as a nitrogen signal, possibly resulting in GB accumulation under DS. (author)

Interactions of calcium ions with weakly acidic active ingredients slow cuticular penetration: a case study with glyphosate.

Science.gov (United States)

Schönherr, Jörg; Schreiber, Lukas

2004-10-20

Potassium and calcium salts of glyphosate were obtained by titrating glyphosate acid with the respective bases to pH 4.0, and rates of penetration of these salts across isolated astomatous cuticular membranes (CMs) were measured at 20 degrees C and 70, 80, 90, and 100% humidity. K-glyphosate exhibited first-order penetration kinetics, and rate constants (k) increased with increasing humidity. Ca-glyphosate penetrated only when the humidity above the salt residue was 100%. At 90% humidity and below, Ca-glyphosate formed a solid residue on the CMs and penetration was not measurable. With Ca-glyphosate, the k value at 100% humidity decreased with time and the initial rates were lower than for K-glyphosate by a factor of 3.68. After equimolar concentrations of ammonium oxalate were added to Ca-glyphosate, high penetration rates close to those measured with K-glyphosate were measured at all humidities. Adding ammonium sulfate or potassium carbonate also increased rates between 70 and 100% humidity, but they were not as high as with ammonium oxalate. The data indicate that at pH 4.0 one Ca2+ ion is bound to two glyphosate anions. This salt has its deliquescence point near 100% humidity. Therefore, it is a solid at lower humidity and does not penetrate. Its molecular weight is 1.82 times larger than that of K-glyphosate, and this greatly slows down rates of penetration, even at 100% humidity. The additives tested have low solubility products and form insoluble precipitates with Ca2+ ions, but only ammonium oxalate binds Ca2+ quantitatively. The resulting ammonium salt of glyphosate penetrates at 70-100% humidity and at rates comparable to K-glyphosate. The results contribute to a better understanding of the hard water antagonism observed with glyphosate. It is argued that other pesticides and hormones with carboxyl functions are likely to respond to Ca2+ ions in a similar fashion. In all of these cases, ammonium oxalate is expected to overcome hard water antagonism

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

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E.A.S. Cícero

2007-09-01

. Plant samples were collected in 12 water bodies in different regions in Brazil (Americana-AMC, Cambaratiba-CBT, Curitiba-CRB, Itapura-ITP, Jaboticabal-JBT, Lagoa Santa-LST, Piraí-PRI, Rio Grande-RGD, Rubinéia-RBN, Salto Grande-SGD, Santa Gertrudes-SGT and Três Lagoas-TLG. The accesses were characterized by the use of RAPD markers (Random Amplified Polymorphic DNA, whose unspecific starters allowed the analysis of polymorphic loci, which evidenced the distribution of the accesses into two groups, with high genetic similarity inside the sub-groups, but with high genetic divergence between them. The use of the RAPD technique evidenced the existence of genetic differences between the accesses. Plants growing in plastic pots (5 L were sprayed with glyphosate at the concentrations of 0.0, 0.6, 1.2, 1.8, 2.4 kg ha-1. Herbicide effects were evaluated on the 7th, 14th, and 21st days after application (DAA with control note attributions (0% without control and 100% leading to the complete death of the plants. No correspondence was observed between the structure of the access groups by the grouping multi-varied analysis using the RAPD technique and water lettuce susceptibility to glyphosate.

Controle de plantas daninhas na cultura de soja resistente ao glyphosate

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Núbia Maria Correia

2010-01-01

Full Text Available O objetivo da pesquisa foi avaliar o controle de plantas daninhas em área cultivada com soja resistente ao herbicida glyphosate, sem a utilização de práticas complementares de manejo de plantas daninhas. Foram desenvolvidos experimentos, em condições de campo, nos anos agrícolas 2005/2006 e 2006/2007 em Jaboticabal (SP. Foram avaliadas duas cultivares de soja resistentes ao glyphosate (CD 214 RR e M-SOY 8008 RR, oito tratamentos de herbicidas (glyphosate, em aplicação única, nas doses de 0,48; 0,72; 0,96 e 1,20 kg ha-1 de equivalente ácido, associadas ou não a aplicação sequencial na dose de 0,48 kg ha-1, além de duas testemunhas, uma capinada e outra mantida infestada. As cultivares de soja influenciaram na infestação das espécies de plantas daninhas na área. Sem a aplicação de glyphosate, houve o predomínio de X. strumarium na área, desfavorecendo a ocorrência de outras espécies. Quando utilizado glyphosate, independentemente da dose, a infestação contabilizada aos 35 e 40 dias após a primeira aplicação, no primeiro e segundo ano, respectivamente, foi baixa. O controle de plantas daninhas na cultura da soja transgênica é diretamente influenciado pela dose de glyphosate, havendo controle satisfatório com a aplicação única de 0,96 kg ha-1 ou a sequencial de 0,48 + 0,48 kg ha-1 de glyphosate. Em situação de menor infestação (2006/2007, a aplicação única de 0,48 kg ha-1 de glyphosate é suficiente para o controle das plantas daninhas. As cultivares de soja transgênica CD 214 RR e M-SOY 8008 RR influenciam diferencialmente a dinâmica das espécies de plantas daninhas, sendo o controle químico mais efetivo na situação de cultivo de M-SOY 8008 RR, em que houve menor diversidade e desenvolvimento das plantas daninhas.

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...

Toxicity of glyphosate as Glypro and LI700 to red-eared slider (trachemys scripta elegans) embryos and early hatchlings.

Science.gov (United States)

Sparling, Donald W; Matson, Cole; Bickham, John; Doelling-Brown, Paige

2006-10-01

More than 8.2 billion ha of cropland, gardens, and forests are treated with the herbicide glyphosate each year. Whereas the toxicity of glyphosate and associated adjuvants has been measured in other vertebrates, few, if any, studies have looked at their effects in reptiles. In some instances, management of turtle habitat requires control of successional stages through application of herbicides. Adults and juvenile turtles may be exposed directly, whereas embryos may contact the chemicals through the soil. In the present study, we exposed eggs of red-eared sliders (Trachemys scripta elegans) to single applications of herbicide ranging from 0 to 11,206 ppm wet weight of glyphosate in Glypro and 0 to 678 ppm of the surfactant, LI700. Hatching success at the highest concentration was significantly lower (73%) than in other treatments (80-100%). At hatch, turtles at the highest concentration weighed less than those at other concentrations. During a 14-d holding period, we observed dose-response relationships in the ability of hatchlings to right themselves when turned on their backs. At the end of the holding period, hatchlings at the highest dose level were still lighter, and somatic indices were lower, than those in other treatments. Genetic damage, as measured by flow cytometry, increased with treatment concentration except for the highest dose. We conclude that because of the high concentrations needed to produce effects and the protection offered by several centimeters of soil or sediment, glyphosate with LI700 poses low levels of risk to red-eared slider embryos under normal field operations with regards to the endpoints measured in the present study. Carelessness in handling glyphosate or failure to follow label directions may produce adverse effects. There also is a risk that the health of turtle embryos may be affected in ways not measured in the present study.

A novel 5-enolpyruvylshikimate-3-phosphate synthase shows high glyphosate tolerance in Escherichia coli and tobacco plants.

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Gaoyi Cao

Full Text Available A key enzyme in the shikimate pathway, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS is the primary target of the broad-spectrum herbicide glyphosate. Identification of new aroA genes coding for EPSPS with a high level of glyphosate tolerance is essential for the development of glyphosate-tolerant crops. In the present study, the glyphosate tolerance of five bacterial aroA genes was evaluated in the E. coli aroA-defective strain ER2799 and in transgenic tobacco plants. All five aroA genes could complement the aroA-defective strain ER2799, and AM79 aroA showed the highest glyphosate tolerance. Although glyphosate treatment inhibited the growth of both WT and transgenic tobacco plants, transgenic plants expressing AM79 aroA tolerated higher concentration of glyphosate and had a higher fresh weight and survival rate than plants expressing other aroA genes. When treated with high concentration of glyphosate, lower shikimate content was detected in the leaves of transgenic plants expressing AM79 aroA than transgenic plants expressing other aroA genes. These results suggest that AM79 aroA could be a good candidate for the development of transgenic glyphosate-tolerant crops.

The rise of glyphosate and new opportunities for biosentinel early-warning studies.

Science.gov (United States)

Kissane, Zoe; Shephard, Jill M

2017-12-01

Glyphosate has become the most commonly used herbicide worldwide and is reputedly environmentally benign, nontoxic, and safe for use near wildlife and humans. However, studies indicate its toxicity is underestimated and its persistence in the environment is greater than once thought. Its actions as a neurotoxin and endocrine disruptor indicate its potential to act in similar ways to persistent organic pollutants such as the organochlorines dichlorodiphenyltrichloroethane (DDT) and dioxin. Exposure to glyphosate and glyphosate-based herbicides for both wildlife and people is likely to be chronic and at sublethal levels, with multiple and ongoing exposure events occurring in urban and agricultural landscapes. Despite this, there has been little research on the impact of glyphosate on wildlife populations, and existing studies appear in the agricultural, toxicology, and water-chemistry literature that may have limited visibility among wildlife biologists. These studies clearly demonstrate a link between chronic exposure and neurotoxicity, endocrine disruption, cell damage, and immune suppression. There is a strong case for the recognition of glyphosate as an emerging organic contaminant and substantial potential exists for collaborative research among ecologists, toxicologists, and chemists to quantify the impact of glyphosate on wildlife and to evaluate the role of biosentinel species in a preemptive move to mitigate downstream impacts on people. There is scope to develop a decision framework to aid the choice of species to biomonitor and analysis methods based on the target contaminant, spatial and temporal extent of contamination, and perceived risk. Birds in particular offer considerable potential in this role because they span agricultural and urban environments, coastal, inland, and wetland ecosystems where glyphosate residues are known to be present. © 2017 Society for Conservation Biology.

Drought Impact Is Alleviated in Sugar Beets (Beta vulgaris L.) by Foliar Application of Fullerenol Nanoparticles.

Science.gov (United States)

Borišev, Milan; Borišev, Ivana; Župunski, Milan; Arsenov, Danijela; Pajević, Slobodanka; Ćurčić, Živko; Vasin, Jovica; Djordjevic, Aleksandar

2016-01-01

Over the past few years, significant efforts have been made to decrease the effects of drought stress on plant productivity and quality. We propose that fullerenol nanoparticles (FNPs, molecular formula C60(OH)24) may help alleviate drought stress by serving as an additional intercellular water supply. Specifically, FNPs are able to penetrate plant leaf and root tissues, where they bind water in various cell compartments. This hydroscopic activity suggests that FNPs could be beneficial in plants. The aim of the present study was to analyse the influence of FNPs on sugar beet plants exposed to drought stress. Our results indicate that intracellular water metabolism can be modified by foliar application of FNPs in drought exposed plants. Drought stress induced a significant increase in the compatible osmolyte proline in both the leaves and roots of control plants, but not in FNP treated plants. These results indicate that FNPs could act as intracellular binders of water, creating an additional water reserve, and enabling adaptation to drought stress. Moreover, analysis of plant antioxidant enzyme activities (CAT, APx and GPx), MDA and GSH content indicate that fullerenol foliar application could have some beneficial effect on alleviating oxidative effects of drought stress, depending on the concentration of nanoparticles applied. Although further studies are necessary to elucidate the biochemical impact of FNPs on plants; the present results could directly impact agricultural practice, where available water supplies are often a limiting factor in plant bioproductivity.

Phytoplankton growth and PSII efficiency sensitivity to a glyphosate-based herbicide (Factor 540®).

Science.gov (United States)

Smedbol, Élise; Lucotte, Marc; Labrecque, Michel; Lepage, Laurent; Juneau, Philippe

2017-11-01

The use of glyphosate-based herbicides in agriculture has increased steadily since the mid 90's and there is now evidence of glyphosate leaching and contamination of aquatic ecosystems. The aim of this study was to evaluate the effects of a glyphosate-based herbicide (Factor 540 ® ) on growth and photosynthetic capacity of algae and cyanobacteria. Six algal and three cyanobacterial species/strains, of three different taxonomic groups, were exposed to five glyphosate concentrations (10, 50, 100, 500 and 1000μgl -1 ) during 48h. All species have significant growth inhibition at concentrations varying between 50 and 500μgl -1 . The photosynthetic response, after glyphosate exposure, varied among species, but a general pattern has emerged. There was an increase in the amount of photons absorbed (ABS/RC), in dissipated (DI O /RC) and trapped (TR O /RC) energy in the photosystem II reaction centers, along with a decreased of the maximum photosystem II quantum yield (F V /F M ) and electron transport per reaction center (ET O /RC). The EC 50 and LOEC values for growth and photosynthesis were calculated and established that growth was the most affected parameter by glyphosate-based herbicide, while parameter TR O /RC was the least affected. All species showed reduced growth at glyphosate concentrations lower than the Canadian standard for the protection of aquatic life, set at 800μgl -1 or the American aquatic life benchmark for acute toxicity in non vascular plants of 12 100μgl -1 questioning the validity of these thresholds in assessing the risks related to the presence of glyphosate and glyphosate-based herbicides in aquatic systems. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Combining glyphosate with burning or mowing improves control of Yellow Bluestem (Bothriochloa ischaemum)

Science.gov (United States)

Robertson, S.; Hickman, Karen R.; Harmoney, Keith R.; Leslie,, David M.

2013-01-01

The invasive yellow bluestem (Bothriochloa ischaemum [L.] Keng) threatens native biodiversity, and its control is of interest to land managers involved in restoration of invaded grasslands. We used single, double, and triple applications of glyphosate (2.125 kg ai.ha-1.application-1) over the course of one growing season in combinations at different timings (early, middle, late season) with and without a mechanical treatment of mowing or burning to determine the most effective control method. One year after treatment, burning and mowing prior to a mid-season single or double early, middle, and/or late season herbicide application resulted in a similar level of control of yellow bluestem relative to a triple herbicide application, all of which had greater control relative to herbicide treatment alone. Reproductive tiller density and visual obstruction increased 2 yr after treatment with two herbicide treatments applied either early and middle season or early and late season, but it was prevented with burning and mowing prior to herbicide application. With the exception of three herbicide applications, combining burning or mowing with herbicide applications provided more effective control of yellow bluestem than any individual herbicide applications. Burning or mowing likely improves glyphosate effectiveness by altering the invasive grass structure so that plants are clear of standing dead and have shorter, active regrowth to enhance herbicide effectiveness. During restoration projects requiring control of invasive yellow bluestem, an effective management option is a combination of mechanical and chemical control.

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. Copyright © 2015 Elsevier Inc. All rights reserved.

Analysis of glyphosate residues in cereals using liquid chromatography-mass spectrometry (LC-MS/MS)

DEFF Research Database (Denmark)

Granby, Kit; Johannesen, S.; Gabrielsen, Martin Vahl

2003-01-01

A fast and specific method for the determination of glyphosate in cereals is described. The method is based on extraction with water by ultrasonication. The samples are cleaned up and separated by high-performance liquid chromatography on a polystyrene-based reverse-phase column (clean-up) in ser......A fast and specific method for the determination of glyphosate in cereals is described. The method is based on extraction with water by ultrasonication. The samples are cleaned up and separated by high-performance liquid chromatography on a polystyrene-based reverse-phase column (clean...... monitored m/z 168--> 150 (glyphosate) and 170-->152 (internal standard 2- 13 (CN)-N-15-glyphosate) for quantification. The mean recovery was 85% ( n =32) at spiking levels from 0.03 to 0.33 mg kg(-1) . From 1998 to 2001, from the analysis of about 50 samples per annum, a reduction in the glyphosate residues...... was observed owing to a Danish trade decision not to use grain with glyphosate residues for milling or bread production....

Glyphosate resistance in common ragweed (Ambrosia artemisiifolia L.)from Mississippi, USA

Science.gov (United States)

Glyphosate is one of the most commonly used broad-spectrum herbicides over the last 40 years. Due to widespread adoption of glyphosate-resistant (GR) crop technology, especially, corn, cotton, and soybean, several weed species in agronomic situations have developed resistance to this herbicide. Rese...

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 ...

Potential use of Lemna minor for the phytoremediation of isoproturon and glyphosate.

Science.gov (United States)

Dosnon-Olette, Rachel; Couderchet, Michel; Oturan, Mehmet A; Oturan, Nihal; Eullaffroy, Philippe

2011-07-01

Pesticides are being detected in water bodies on an increasingly frequent basis. The present study focused on toxicity and phytoremediation potential of aquatic plants to remove phytosanitary products from contaminated water. We investigated the capacity of Lemna minor (L. minor) to eliminate two herbicides isoproturon and glyphosate from their medium. Since phytoremediation relies on healthy plants, pesticide toxicity was evaluated by exposing plants to 5 concentrations (0-20 microg L(-1) for isoproturon and 0-120 microg L(-1) for glyphosate) in culture media for 4 d using growth rate and chlorophyll a fluorescence as endpoints. At exposure concentrations of 10 microg x L(-1) for isoproturon and 80 microg x L(-1) for glyphosate, effects on growth rate and chlorophyll fluorescence were minor (isoproturon and glyphosate, respectively.

Determination of the Optimum Concentration and Time of Salicylic Acid Foliar Application for Improving Barley Growth under Non-Saline and Saline Conditions

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GH. Ranjbar

2017-02-01

Full Text Available In a 2yrs field study the effect of concentration and time of salicylic acid (SA foliar application on growth of barley under non-saline and saline (2 and 12 dS m-1 of NaCl, respectively conditions was evaluated in National Salinity Research Center of Iran, Yazd, central Iran during 2012-2014 growing seasons. The treatments of SA (11 treatments included without SA and SA foliar application at 0.0, 0.35, 0.70, 1.05, 1.40 and 1.75 mM applied at tillering + stem elongation + ear emergence or stem elongation + ear emergence. Salt stress led to significant decreases in seed yield and yield components; however, grain yield of barley plants were considerably increased when subjected to SA. This positive impact of SA was due probably to its effect on grain number. Average of grain yield in 0.0, 0.35, 0.70, 1.05, 1.40 and 1.75 mM SA concentrations were 496.1, 539.7, 538.5, 553.8, 517.4 and 501.3 g m-2 under non-saline and 189.2, 212.5, 219.1, 206.9, 200.3 and 182.3 g m-2 under saline conditions, respectively. Considering the negative correlation between sodium concentration in shoot and grain yield, modulating role of exogenous SA on adverse effect of salinity might be related to a SA-induced lowered Na+ concentration in such organs. The appropriate treatment seems to be SA foliar application at 1.05 mM for non-saline and 0.70 mM for saline conditions applied at stem elongation + ear emergence, as they increased grain yield by 16.6% and 18.6%, respectively. The result of this study revealed that higher concentration or frequency of SA application could be associated with negative impacts on barley.

The fate of glyphosate in water hyacinth and its physiological and biochemical influences on growth of algae

International Nuclear Information System (INIS)

Tsai, Baolong.

1989-01-01

Absorption, translocation, distribution, exudation, and guttation of 14 C-glyphosate in water hyacinth (Eichhornia crassipes) were studied. Glyphosphate entered the plant by foliage and solution treatment. Plants were harvested and separated into the following parts: treated leaf blade, treated leaf petiole, young leaf blade, young leaf petiole, old leak blade, old leaf petiole, and root. Each part was extracted with methanol. Treated leaves, which exist only in foliage treatment, were washed with water and chloroform to remove the glyphosate residues. All 14 C counting was made by liquid scintillation spectrometry. Autoradiography was used to locate 14 C-glyphosate after foliage treatment. Results indicated that glyphosate can be absorbed from the leaf surface and translocated rapidly through phloem tissues into the whole plant body. The roots of water hyacinth absorbed glyphosate without vertical transport. Guttation of glyphosate occurred in treated leaf tips. Exudation of glyphosate from roots of water hyacinth occurred within 8 hr after foliage treatment. Chlorella vulgaris, Chlamydomonas reihardii, Anabaena cylindrica, and Chroococcus turgidus were used to explore the physiological and biochemical effects of glyphosate on algae. Spectrophotometric assays were performed for algal growth, chlorophyll, carotenoids, phycobiliprotein, carbohydrate, and protein. TLC procedures and an image analyzer were used to detect the metabolites of glyphosate inside algal cells. The common visible symptom of glyphosate toxicity in all algal cells were bleaching effect and reduction of contents of carbohydrate, protein, and pigments. The results highly suggested that glyphosate injured the algal cells by destruction of photosynthetic pigments and resulted in lowering the contents of carbohydrate and protein in algal cells

Foliar application with nano-silicon reduced cadmium accumulation in grains by inhibiting cadmium translocation in rice plants.

Science.gov (United States)

Chen, Rui; Zhang, Changbo; Zhao, Yanling; Huang, Yongchun; Liu, Zhongqi

2018-01-01

Nano-silicon (Si) may be more effective than regular fertilizers in protecting plants from cadmium (Cd) stress. A field experiment was conducted to study the effects of nano-Si on Cd accumulation in grains and other organs of rice plants (Oryza sativa L. cv. Xiangzaoxian 45) grown in Cd-contaminated farmland. Foliar application with 5~25 mM nano-Si at anthesis stage reduced Cd concentrations in grains and rachises at maturity stage by 31.6~64.9 and 36.1~60.8%, respectively. Meanwhile, nano-Si application significantly increased concentrations of potassium (K), magnesium (Mg), and iron (Fe) in grains and rachises, but imposed little effect on concentrations of calcium (Ca), zinc (Zn), and manganese (Mn) in them. Uppermost nodes under panicles displayed much higher Cd concentration (4.50~5.53 mg kg -1 ) than other aerial organs. After foliar application with nano-Si, translocation factors (TFs) of Cd ions from the uppermost nodes to rachises significantly declined, but TFs of K, Mg, and Fe from the uppermost nodes to rachises increased significantly. High dose of nano-Si (25 mM) was more effective than low dose of nano-Si in reducing TFs of Cd from roots to the uppermost nodes and from the uppermost nodes to rachises. These findings indicate that nano-Si supply reduces Cd accumulation in grains by inhibiting translocation of Cd and, meanwhile, promoting translocation of K, Mg, and Fe from the uppermost nodes to rachises in rice plants.

The influence of organic matter on sorption and fate of glyphosate in soil - Comparing different soils and humic substances

Energy Technology Data Exchange (ETDEWEB)

Albers, Christian N., E-mail: calbers@ruc.d [Dept. of Geochemistry, Geological Survey of Denmark and Greenland, DK-1350 Copenhagen (Denmark); Dept. of Science, Systems and Models, Roskilde University, DK-4000 Roskilde (Denmark); Banta, Gary T. [Dept. of Environmental, Social and Spatial Change, Roskilde University, DK-4000 Roskilde (Denmark); Hansen, Poul Erik [Dept. of Science, Systems and Models, Roskilde University, DK-4000 Roskilde (Denmark); Jacobsen, Ole S. [Dept. of Geochemistry, Geological Survey of Denmark and Greenland, DK-1350 Copenhagen (Denmark)

2009-10-15

Soil organic matter (SOM) is generally believed not to influence the sorption of glyphosate in soil. To get a closer look on the dynamics between glyphosate and SOM, we used three approaches: I. Sorption studies with seven purified soil humic fractions showed that these could sorb glyphosate and that the aromatic content, possibly phenolic groups, seems to aid the sorption. II. Sorption studies with six whole soils and with SOM removed showed that several soil parameters including SOM are responsible for the strong sorption of glyphosate in soils. III. After an 80 day fate experiment, approx40% of the added glyphosate was associated with the humic and fulvic acid fractions in the sandy soils, while this was the case for only approx10% of the added glyphosate in the clayey soils. Glyphosate sorbed to humic substances in the natural soils seemed to be easier desorbed than glyphosate sorbed to amorphous Fe/Al-oxides. - Glyphosate was sorbed by purified humic substances and a significant amount of glyphosate was found to be associated with soil organic matter in whole soils.

The influence of organic matter on sorption and fate of glyphosate in soil - Comparing different soils and humic substances

International Nuclear Information System (INIS)

Albers, Christian N.; Banta, Gary T.; Hansen, Poul Erik; Jacobsen, Ole S.

2009-01-01

Soil organic matter (SOM) is generally believed not to influence the sorption of glyphosate in soil. To get a closer look on the dynamics between glyphosate and SOM, we used three approaches: I. Sorption studies with seven purified soil humic fractions showed that these could sorb glyphosate and that the aromatic content, possibly phenolic groups, seems to aid the sorption. II. Sorption studies with six whole soils and with SOM removed showed that several soil parameters including SOM are responsible for the strong sorption of glyphosate in soils. III. After an 80 day fate experiment, ∼40% of the added glyphosate was associated with the humic and fulvic acid fractions in the sandy soils, while this was the case for only ∼10% of the added glyphosate in the clayey soils. Glyphosate sorbed to humic substances in the natural soils seemed to be easier desorbed than glyphosate sorbed to amorphous Fe/Al-oxides. - Glyphosate was sorbed by purified humic substances and a significant amount of glyphosate was found to be associated with soil organic matter in whole soils.

Differential content of glyphosate and its metabolites in Digitaria insularis biotypes

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Leonardo Bianco de Carvalho

2013-07-01

Full Text Available Experiments were carried out in controlled conditions to analyze the role of metabolism of glyphosate in Digitaria insularis (sourgrass biotypes with differential response to the herbicide. Contents of glyphosate, aminomethylphosphonic acid (AMPA, glyoxylate, and sarcosine was detected in leaf tissues by using reversed-polarity capillarity electrophoresis. Glyphosate content in the A biotype increased from 19.7 up to 65.5 µg g fresh weight-1, whereas decreasing from 19.9 down to 5.0 µg g fresh weight-1 in the B biotype, from 48 up to 168 hours after treatment. At 168 hours after treatment, percentage of the sum of AMPA, glyoxylate, and sarcosine was > 56% in the B biotype, whereas a small percentage of metabolites (< 10% was found in the A biotype. Thus, the faster herbicide degradation in the B biotype is evidence that a differential metabolism of glyphosate can be conferring its lesser susceptibility to the herbicide.

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

DEFF Research Database (Denmark)

Vendelboe, Anders Lindblad; de Jonge, Hubert; Møldrup, Per

2012-01-01

Glyphosate is one of the world’s most extensively used weed control agents. Glyphosate, and its metabolite aminomethylphosphonic acid (AMPA), are suspected to be hazardous to human health and the aquatic environment. In Denmark, the extensive use has resulted in an increasing number of occurrences......Cell, will decrease the workload and number of samples freeing up funds for larger monitoring programs. When installed in a well the SorbiCell will continuously sample the water giving either a flux-weighed or time-weighted average measurement of the glyphosate/AMPA concentration throughout the sampling period....... It may therefore be possible to measure lower concentrations as the glyphosate/AMPA sorbed in the SorbiCell is an accumulated measurement. Also, glyphosate/AMPA associated with sudden flush events will be detected by the SorbiCells, while such events may pass between two consecutive grab samples...

Novel AroA from Pseudomonas putida Confers Tobacco Plant with High Tolerance to Glyphosate

Science.gov (United States)

Yan, Hai-Qin; Chang, Su-Hua; Tian, Zhe-Xian; Zhang, Le; Sun, Yi-Cheng; Li, Yan; Wang, Jing; Wang, Yi-Ping

2011-01-01

Glyphosate is a non-selective broad-spectrum herbicide that inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS, also designated as AroA), a key enzyme in the aromatic amino acid biosynthesis pathway in microorganisms and plants. Previously, we reported that a novel AroA (PpAroA1) from Pseudomonas putida had high tolerance to glyphosate, with little homology to class I or class II glyphosate-tolerant AroA. In this study, the coding sequence of PpAroA1 was optimized for tobacco. For maturation of the enzyme in chloroplast, a chloroplast transit peptide coding sequence was fused in frame with the optimized aroA gene (PparoA1optimized) at the 5′ end. The PparoA1optimized gene was introduced into the tobacco (Nicotiana tabacum L. cv. W38) genome via Agrobacterium-mediated transformation. The transformed explants were first screened in shoot induction medium containing kanamycin. Then glyphosate tolerance was assayed in putative transgenic plants and its T1 progeny. Our results show that the PpAroA1 from Pseudomonas putida can efficiently confer tobacco plants with high glyphosate tolerance. Transgenic tobacco overexpressing the PparoA1optimized gene exhibit high tolerance to glyphosate, which suggest that the novel PpAroA1 is a new and good candidate applied in transgenic crops with glyphosate tolerance in future. PMID:21611121

Foliar uptake of zinc by vascular plants. Radiometric study

International Nuclear Information System (INIS)

Maresova, J.; Remenarova, L.; Hornik, M.; Pipiska, M.; Augustin, J.; Lesny, J.

2012-01-01

The aim of this paper was to obtain quantitative data of foliar uptake kinetics and long distance transport of zinc in tobacco (Nicotiana tabacum L.) and hop (Humulus lupulus L.) plants. Zinc was used as a model of microelement and toxic metal, tobacco and hop as a representatives of agriculturally important plants. A tip of leaf blade was immersed in the solution spiked with 65 ZnCl 2 and foliar uptake and translocation to other parts of the plant grown in nutrient solution was measured by gamma-spectrometry and autoradiography. We found that foliar zinc uptake by both plants is dependent on the initial metal concentration within the range C 0 = 10-100 μmol dm -3 ZnCl 2 . Zinc is immobilized mainly in immersed part of the contact leaf and only 0 = 0.1 mmol dm -3 ZnCl 2 concentrations >2.5 mg/g Zn and 4.8 mg/g Zn (dry wt.) in immersed part of tobacco and hop leaf plant, respectively were found after 5 days of exposure. Low mobility of zinc entering the plant via the leaf surface can be attributed to the immobilization of zinc into Zn-ligand complexes with high stability constants log K at pH 6.0-8.0, such as the reaction products of Zn 2+ ions with citric acid, histidine or phosphates. Zinc can be extracted from dried leaves by the solutions of inorganic salts, carboxylic acids, amino acids and synthetic complexing ligands such as EDTA. Anionic (SDS) and non-ionic (Tween 40) surfactants causes the decrease of the Zn foliar uptake, but not translocation of Zn from the contact leaf area. Obtained data are discussed from the point of view of possible limited efficiency of liquid formulations designed for practical applications as Zn foliar fertilizers. (author)

Target-site mutations conferring resistance to glyphosate in feathertop Rhodes grass (Chloris virgata) populations in Australia.

Science.gov (United States)

Ngo, The D; Krishnan, Mahima; Boutsalis, Peter; Gill, Gurjeet; Preston, Christopher

2018-05-01

Chloris virgata is a warm-season, C 4 , annual grass weed affecting field crops in northern Australia that has become an emerging weed in southern Australia. Four populations with suspected resistance to glyphosate were collected in South Australia, Queensland and New South Wales, Australia, and compared with one susceptible (S) population to confirm glyphosate resistance and elucidate possible mechanisms of resistance. Based on the rate of glyphosate required to kill 50% of treated plants (LD 50 ), glyphosate resistance (GR) was confirmed in four populations of C. virgata (V12, V14.2, V14.16 and V15). GR plants were 2-9.7-fold more resistant and accumulated less shikimate after glyphosate treatment than S plants. GR and S plants did not differ in glyphosate absorption and translocation. Target-site EPSPS mutations corresponding to Pro-106-Leu (V14.2) and Pro-106-Ser (V15, V14.16 and V12) substitutions were found in GR populations. The population with Pro-106-Leu substitution was 2.9-4.9-fold more resistant than the three other populations with Pro-106-Ser substitution. This report confirms glyphosate resistance in C. virgata and shows that target-site EPSPS mutations confer resistance to glyphosate in this species. The evolution of glyphosate resistance in C. virgata highlights the need to identify alternative control tactics. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

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

Science.gov (United States)

Martínez Gil, Pablo; Laguarda-Miro, Nicolas; Camino, Juan Soto; Peris, Rafael Masot

2013-10-15

Pulsed voltammetry has been used to detect and quantify glyphosate on buffered water in presence of ammonium nitrate and humic substances. Glyphosate is the most widely used herbicide active ingredient in the world. It is a non-selective broad spectrum herbicide but some of its health and environmental effects are still being discussed. Nowadays, glyphosate pollution in water is being monitored but quantification techniques are slow and expensive. Glyphosate wastes are often detected in countryside water bodies where organic substances and fertilizers (commonly based on ammonium nitrate) may also be present. Glyphosate also forms complexes with humic acids so these compounds have also been taken into consideration. The objective of this research is to study the interference of these common pollutants in glyphosate measurements by pulsed voltammetry. The statistical treatment of the voltammetric data obtained lets us discriminate glyphosate from the other studied compounds and a mathematical model has been built to quantify glyphosate concentrations in a buffer despite the presence of humic substances and ammonium nitrate. In this model, the coefficient of determination (R(2)) is 0.977 and the RMSEP value is 2.96 × 10(-5) so the model is considered statistically valid. Copyright © 2013 Elsevier B.V. All rights reserved.

Foliar application of processed calcite particles improves leaf photosynthesis of potted Vitis vinifera L. (var. ‘Cot’ grown under water deficit

Directory of Open Access Journals (Sweden)

Faouzi Attia

2014-12-01

Significance and impact of the study: In the context of climate change, grapevine will most likely experience long periods of drought during its seasonal cycle. Foliar application of processed mineral particles is widely used to reduce heat stress in perennial fruit crops. Here, the micronized calcite Megagreen® does improve photosynthesis of water stressed grapevines.

Effects of glyphosate exposure on sperm concentration in rodents: A systematic review and meta-analysis.

Science.gov (United States)

Cai, Wenyan; Ji, Ying; Song, Xianping; Guo, Haoran; Han, Lei; Zhang, Feng; Liu, Xin; Zhang, Hengdong; Zhu, Baoli; Xu, Ming

2017-10-01

Correlation between exposure to glyphosate and sperm concentrations is important in reproductive toxicity risk assessment for male reproductive functions. Many studies have focused on reproductive toxicity on glyphosate, however, results are still controversial. We conducted a systematic review of epidemiological studies on the association between glyphosate exposure and sperm concentrations of rodents. The aim of this study is to explore the potential adverse effects of glyphosate on reproductive function of male rodents. Systematic and comprehensive literature search was performed in MEDLINE, TOXLINE, Embase, WANFANG and CNKI databases with different combinations of glyphosate exposure and sperm concentration. 8 studies were eventually identified and random-effect model was conducted. Heterogeneity among study results was calculated via chi-square tests. Ten independent experimental datasets from these eight studies were acquired to synthesize the random-effect model. A decrease in sperm concentrations was found with mean difference of sperm concentrations(MDsperm)=-2.774×10 6 /sperm/g/testis(95%CI=-0.969 to -4.579) in random-effect model after glyphosate exposure. There was also a significant decrease after fitting the random-effect model: MDsperm=-1.632×10 6 /sperm/g/testis (95%CI=-0.662 to -2.601). The results of meta-analysis support the hypothesis that glyphosate exposure decreased sperm concentration in rodents. Therefore, we conclude that glyphosate is toxic to male rodent's reproductive system. Copyright © 2017. Published by Elsevier B.V.

Manejo químico de plantas adultas de Digitaria insularis com glyphosate isolado e em mistura com chlorimuronethyl ou quizalofop-p-tefuril em área de plantio direto Chemical management of adult Digitaria insularis with glyphosate alone and mixture with chlorimuron-ethyl or quizalofop-p-tefuril in a no-tillage field

Directory of Open Access Journals (Sweden)

Núbia Maria Correia

2009-09-01

, resultaram em melhor controle da planta daninha.The objective of this work was to evaluate the efficiency of the herbicide glyphosate used alone, in combination with chlorimuron-ethyl and quizalofop-p-tefuril as well as the effect of the addition of mineral oil to control adult Digitaria insularis plants in a no-tillage field. Two experiments were conducted under field conditions from November 2005 to February 2006 and from November 2006 to January 2007, at Jaboticabal, São Paulo State, Brazil. Experiments were set in randomized blocks with four replications. In the first experiment (2005/06 it were tested eight combinations among glyphosate (0.72; 1.44; 2.16 and 2.88 kg ha-1, chlorimuron-ethyl (0 and 10 g ha-1 mineral oil (0; 0.5 and 1.0 L ha-1 and an infested, untreated control. In the second experiment (2006/07 it were tested six associations among glyphosate (1.44; 2.16 and 2.88 kg ha-1, quizalofop-p-tefuril (0 and 120 g ha-1, quizalofop-p-tefuril (120 g ha-1 alone and combined to three (0; 0.72 and 1.44 kg ha-1 glyphosate doses, sprayed 15 days after the first application, besides an infested and untreated control. In 2005/06, plants sprayed with higher glyphosate doses, alone or combined with chlorimuron, showed severe injuries, with a control classification ranging from good (71 to 80% to very good (81 to 90%. Over time plants tillered and showed their recovery potential and the inefficiency of the herbicides to control this weed species. The addition of mineral oil to glyphosate and chlorimuron solution did not entrance its efficiency. In the other experiment, the quizalofop alone or associated with glyphosate, combined to sequential application of glyphosate 1.44 kg ha-1, resulted in the best weed control.

Global research production in glyphosate intoxication from 1978 to 2015: A bibliometric analysis.

Science.gov (United States)

Zyoud, S H; Waring, W S; Al-Jabi, S W; Sweileh, W M

2017-10-01

Glyphosate (N-phosphonomethylglycine) has been used as a broad-spectrum herbicide that has been widely used in the agricultural industry and also available for home use. The main aim of this study is to present a general overview of glyphosate intoxication-related publications from its introducing since the early 1970s using bibliometric technique. On June 23, 2016, a literature search of the Scopus database was performed. We then extracted and analyzed the data using well-established qualitative and quantitative bibliometric indices: Publication year, affiliation, document type, country name, subject category, journal name, publishing language, and collaboration and citation patterns. We recognized a total of 3735 publications on glyphosate published between 1973 and 2015. There were 875 publications related to glyphosate intoxication in the Scopus database published between 1978 and 2015. Articles (757) comprised 86.5% of the total publications, followed by reviews (41; 4.7%). Most publications were published in English (87.9%), followed by Portuguese (6.6%). The number of publications related to glyphosate intoxication increased from 44 in 1978-1987 up to 152 in 1996-2005 and then quadrupled in 2006-2015. The United States was the leading country with 180 documents representing 20.6%, followed by Brazil (120; 13.7%), Canada (78; 8.9%), Argentina (61; 7.0%), and France (57; 6.5%). The 85.6% of the publications was cited, and the average of citation per document was 17.13 with h-index of 55. Furthermore, the United States achieved the highest h-index of 33. Most of the global international collaborations are made with researchers from the United States, who collaborated with 23 countries/territories in 44 publications. The trends in global glyphosate-related research between 1978 and 2015 were evaluated by a bibliometric technique. Results showed that English was the leading publishing language, and the major publication type was original article. Findings showed

14C-glyphosate mineralization and follow up of the dynamics of Pseudomonas sp. populations in three soils under different uses in Tolima (Colombia)

OpenAIRE

Liliana Figueroa del Castillo; Myriam Rocío Melgarejo P; Cilia L. Fuentes de Piedrahíta; Amanda Lozano de Yunda

2010-01-01

The capacity of Pseudomonas sp. to degrade different pesticides has been the object of numerous studies; due to this, its dynamics was evaluated and the effect of the application of glyphosate (Roundup®) in soils of Tolima, taxonomically classified as Entic haplustolls, Typic ustipsamments, and Inceptic haplustalfs with coverage of secondary forest, stubble and sorghum crop, respectively, through the in vitro 14C-glyphosate mineralization. These soils were subjected to presence/absence of hea...

Effect of foliar fertilizer and fungicidal protection against leaf spot diseases on winter wheat

Directory of Open Access Journals (Sweden)

Agnieszka Mączyńska

2012-12-01

Full Text Available Field experiments were carried out in the seasons 2000/2001 and 2001/2002 in Plant Protection Institute, Sooenicowice Branch to assess the influence of foliar fertilizers such as Ekolist PK 1, Ekolist Mg, Mikrosol Z and Urea on healthiness of winter wheat. Foliar fertilizers were mixed with fungicides. The fungicides were applied at full or half recommended doses. The effect of the disease on wheat leaves was evaluated three times in each vegetation season. Remaining green leaf area (GLA of leaves was also determined. GLA of the leaves F-1 was not significantly different for each combination with different fertilization and different levels of chemical treatment. The application of foliar fertilizer only had no effect on green leaf area (GLA. The results indicate that foliar fertilization of all experimental plots improved leaf condition and therefore halted the development of wheat leaf diseases. The increases of 1000 grain mass and yield was high for each plot where a fertilizer and a full or half dose of a fungicide was applied. Foliar fertilizing with no chemical control had no proven effect on studied parameters.

Glyphosate sorption and desorption in soils with distinct phosphorus levels

International Nuclear Information System (INIS)

Prata, Fabio; Cardinali, Vanessa Camponez do Brasil; Tornisielo, Valdemar Luiz; Regitano, Jussara Borges; Lavorenti, Arquimedes

2003-01-01

The sorption of glyphosate by soils occurs due to the inner sphere complex formation with metals of soil oxides, which are related to the soil phosphate adsorption capacity. The aim of this study was to evaluate the effects of increasing rates of phosphorus on sorption and desorption of glyphosate in three soils with different mineralogical attributes. Soils were a Rhodic Kandiudalf, an Anionic Acrudox and a Typic Humaquept. Soil samples were amended with Kh 2 PO 4 at equivalent rates of 0; 1,000; 5,000; 20,000 and 50,000 kg ha -1 of P 2 O 5 , which are high from the agricultural point of view, but necessary in order to perform sorption and desorption studies. The experimental design consisted of a completely randomized factorial: 2 soils x 5 phosphorus rates and 3 replicates. For the sorption experiments, five glyphosate solutions were employed (0.42; 0.84; 1.68; 3.36 and 6.72 mg L -1 ), with a 14 C radioactivity of 0.233 kBq mL -1 . Four steps of the desorption procedures withCaCl 2 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)

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.

DESEMPENHO DA APLICAÇÃO FOLIAR DE ZINCO EM FEIJOEIRO

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Hugo Alexandre Coelho

2010-06-01

Full Text Available The nutritional requirements of crops, in general, becomes more intense with the beginning of the reproductive phase, being more critical at the time of seed formation, when considerable amounts of nutrients are they translocation, this requirement should be increased to the fact that nutrients are essential to training and development of new bodies of booking. This study aimed to evaluate the agronomic efficiency of foliar application of zinc (zinc oxide Zn 700 g L-1 in bean plant, compared to leaf application of zinc sulphate (ZnSO4 and control (without application of Zn. The experiment was installed in the Faculty of Agricultural Sciences - UNESP / Campus de Botucatu-SP. Was placed in containers with a capacity of 20L of soil and leaf applications encompassing four schemes and two of rain, with 5 replicates per treatment, a total of 40 vessels. The results for the factorial design did not show in general, significantly different answers when evaluated on the simulation of rain or the lack of simulation. The treatment (700g L-1 of ZnO has demonstrated agronomic efficiency as its foliar application, with results equal or exceed the application of ZnSO4 and control when applied at the same dose of Zn.

Glyphosate sorption/desorption on biochars – Interactions of physical and chemical processes

Science.gov (United States)

BACKGROUND: Biochar, a carbon-rich product of biomass pyrolysis, could limit glyphosate transport in soil and remediate contaminated water. The present study investigates the sorption/desorption behavior of glyphosate on biochars prepared from different hardwoods at temperatures ranging from 350°C t...

Glyphosate and AMPA distribution in wind-eroded sediment derived from loess soil

NARCIS (Netherlands)

Martins Bento, Celia; Goossens, Dirk; Rezaei, Mahrooz; Riksen, M.J.P.M.; Mol, J.G.J.; Ritsema, C.J.; Geissen, V.

2017-01-01

Glyphosate is one of the most used herbicides in agricultural lands worldwide. Wind-eroded sediment and dust, as an environmental transport pathway of glyphosate and of its main metabolite aminomethylphosphonic acid (AMPA), can result in environmental- and human exposure far beyond the agricultural

PHYSIOLOGICAL MATURATION IN SEEDS OF SWEET SOGHUM FOR FOLIAR FERTILISATION WITH SILICATE

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BRUNO FRANÇA DA TRINDADE LESSA

2017-01-01

Full Text Available The aim of this study was to evaluate physiological quality in seeds of sweet sorghum grown under semi-arid conditions, and to determine the age of physiological maturity of the seeds as a function of the foliar application of potassium silicate. The experiment was carried out at the Curu Valley Experimental Farm, in Pentecoste in the state of Ceará, during the rainy seasons of 2014 and 2015. The BRS 506 and BRS 511 varieties were used, under foliar fertilisation with potassium silicate at doses of 500, 1000 and 1500 mL.ha -1, in addition to the control lots (with no application; harvesting was at four periods, 30, 37, 44 and 51 days after full bloom (DAB. The percentage and speed of germination were evaluated, together with the accelerated ageing test and seedling growth. The seeds presented greater than 90% germination from 37 DAB, reaching high seedling vigour at 51 DAB. Foliar fertilisation with potassium silicate under the conditions of the experiment resulted in an increase in the physiological quality of the seeds. The BRS 506 and BRS 511 cultivars displayed the highest physiological quality between 49 and 53 DAF.

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