Letteratura scientifica selezionata sul tema "Plants, Effect of herbicides on"
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Articoli di riviste sul tema "Plants, Effect of herbicides on"
1
Swanson, Bert T., e James B. Calkins. "Weed Control Strategies for Field- and Container-grown Herbaceous Perennials". HortScience 30, n. 4 (luglio 1995): 894E—894. http://dx.doi.org/10.21273/hortsci.30.4.894e.
Testo completoAbstract (sommario):
Fourteen herbicides or herbicide combinations, a wood chip mulch, a chipped rubber tire mulch, and a newspaper mulch were evaluated for weed control efficacy and potential phytotoxicity using 12 species of herbaceous perennials under field-growing conditions. Nineteen herbicides or herbicide combinations were similarly evaluated under container-growing conditions using 11 species of herbaceous perennials. The effect of herbicide application time also was monitored through application of herbicides to dormant and actively growing plants. Herbicides and mulch treatments were compared to weeded and nonweeded controls. Herbicide phytotoxicity effects were dependent on the age and species of the herbaceous perennial and herbicide application timing. Herbicide injury was generally greater for newly established plants compared to established plants. Although injury was usually reduced when herbicides were applied to dormant plants, injury was sometimes greater when herbicides were applied in early spring compared to applications made in late spring after complete herbaceous perennial emergence. This effect resulted in injury to young shoots that had emerged before the earliest possible time that herbicides could be applied in early spring. A wood chip mulch provided the most effective weed control and highest quality plants under field growing conditions. Several of the herbicides evaluated demonstrated potential for weed control in both field and container herbaceous perennial production systems and landscape plantings.
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Guralchuk, Zh Z., A. M. Sychuk e O. V. Gumenyuk. "Influence of herbicide on plants in connection with formation of arbuscular mycorrhizal symbiosis". Faktori eksperimental'noi evolucii organizmiv 23 (9 settembre 2018): 369–73. http://dx.doi.org/10.7124/feeo.v23.1043.
Testo completoAbstract (sommario):
Aim. The aim of the work is to analyze the available literature data on the effect of herbicides on the formation of mycorrhizal symbiosis. Results. The article gives a brief overview of the influence of herbicides with different mechanism of action on the formation and functioning of arbuscular mycorrhizal symbiosis. The direct and indirect effects of herbicides on the AM fungi, the different selectivity of AM fungi to herbicides and other factors influencing the effect of herbicides on biodiversity of AM fungi and the formation of mycorrhizal symbiosis are considered. Conclusions. Herbicides with different mechanism of action can have a significant effect on the diversity of AM fungi present in the soil, the formation and functioning of mycorrhizal symbiosis. Their effect on the AM fungi can be either direct or indirect due to the influence on the host plant. AM fungi, in turn, can also influence the selectivity of the plant to herbicides. Studies on the effect of herbicides on mycorrhizal symbiosis may be important for increasing the herbicide efficiency.
Keywords: herbicides, arbuscular mycorrhizal fungi, mycorrhizal symbiosis.
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Dear, BS, GA Sandral e NE Coombes. "Change in stomatal resistance and water use in subterranean clover (Trifolium subterraneum L.) in response to broadleaf herbicides". Australian Journal of Agricultural Research 47, n. 4 (1996): 625. http://dx.doi.org/10.1071/ar9960625.
Testo completoAbstract (sommario):
The effect of 5 broadleaf herbicides on the water use and stomatal resistance of 2 cultivars of subterranean clover (Trifolium subterraneum L.) was examined in a glasshouse study. The herbicide treatments 2,4-DB, MCPA, bromoxynil, MCPA+terbutryn, and MCPA+diuron were applied at 6 rates at 2 times (14 May, 14 June) to plants at 2 leaf stages (3-4 and 8-10 leaves). Each of the herbicides reduced water use by the clover within 24 h, the size of the reduction increasing with the rate of herbicide applied. The herbicide treatments MCPA+terbutryn, MCPA+diuron, and bromoxynil caused the largest reductions (44-52%) in total water use over the 30-day period when applied at the recommended rate, and MCPA and 2,4-DB the least reduction (16-22%). Stomatal resistance increased substantially within 2 days of application of each of the herbicides. The magnitude of the change differed with herbicide and increased with herbicide rate. The effect of the herbicides on stomatal resistance declined 10-20 days after herbicide application in all treatments except 2,4-DB, but stomatal resistance of all herbicide-treated plants was still higher than the control 30 days after herbicide application. The herbicides LICPA+terbutryn and LlCPA+diuron and bromoxynil caused the largest increase in stomatal resistance and 2,4-DB the least. Stomatal resistance was found to be highly negatively correlated with daily water use by the clover plants at 2 days (r = -0.84, P < 0.01) and 30 days (r = -0.88, P < 0.01) after herbicide application. All of the herbicides reduced the LA1 of the plants, the effect increasing as the herbicide rate increased. Herbicide and herbicide rate had the largest effect on both water use and stomatal resistance; the effect of cultivar, leaf stage, and spraying time accounted for a relatively small proportion of the variance. The findings support the hypothesis that some broadleaf herbicides can result in a water-saving effect in subterranean clover swards through increasing stomatal resistance and decreasing the LAI, thereby potentially reducing moisture stress during seed set.
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Elezovic, Ibrahim, Dragana Bozic e Sava Vrbnicanin. "Absorption, translocation and metabolism of the sulfonylurea herbicides in plants". Pesticidi 18, n. 4 (2003): 205–22. http://dx.doi.org/10.2298/pif0304205e.
Testo completoAbstract (sommario):
Absorption, translocation and metabolism are processes affecting the efficacy of sulfonylurea herbicides. These processes contribute significantly to selectivity but are also known to effect the development of plant resistance to this group of herbicides. Sulfonylureas may be absorbed by both ground and above ground plant parts. The level of absorption depends on numerous factors such as: development stage of the plant, ambient temperature, soil humidity, fertilizers added to herbicides, application in combination with other herbicides, sufactants, plant cultivars, mode of herbicide application, various additives. Having been absorbed, the herbicide moves to the place of action whereby the direction of translocation depends on the mode of absorption. Foliary absorbed sulfonylureas are primarily basipetally translocated. Acropetal translocation is correlated to root absorption. In addition, some herbicides belonging to this group are translocated in both directions. The level and rate of translocation depend on: soil humidity, antagonistic effect of other herbicides (in case of application of herbicide combinations), additives, fertilizers etc. Sulfonylureas in plants are subjected to different metabolic changes which mostly contribute to the inactivation. These transformations are considered to be catalyzed by the cytochrom P-450 monooxigenase enzymic system. Eventually, this process is also known to be affected by numerous factors such as: temperature, soil humidity, plant cultivars, mixtures with other pesticides etc.
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Brant, V., J. Pivec, K. Hamouzová, P. Zábranský, J. Satrapová e M. Škeříková. "Determination of the influence of herbicides on dicotyledons plant transpiration using the sap flow method". Plant, Soil and Environment 60, No. 12 (28 novembre 2014): 562–68. http://dx.doi.org/10.17221/655/2014-pse.
Testo completoAbstract (sommario):
Physiological parameters are sensitive and provide information on the toxicity of herbicides in plants. The impact of herbicide application on plant transpiration was evaluated by the sap flow method during 2009–2011. The aim of this work was to verify the sap flow method for determining the effect of herbicides on the basis of continuous measurements of the transpiration flow. Helianthus annuus was used as a model plant species. The two different herbicides tested in this study differed by the effect of active ingredients bromoxynil and clopyralid. The water flow was measured using sap flow meter T4.2. The impact of herbicides was assessed by comparing measured transpiration rate (Q) after herbicide application with an extrapolation of transpiration rate of plants before herbicide treatment (Q<sub>calc</sub>). After treatment with bromoxynil the Q values decreased significantly compared to Q<sub>calc</sub>. For plants treated by clopyralid, the decline of actual transpiration (Q) compared with the modelled one (Q<sub>calc</sub>) was less substantial and the plants continued to transpire after the treatment. The effect of herbicides was also verified using infrared gas analyser and chlorophyll fluorescence meter.
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Lobachev, Yuriy Viktorovich, e Valeriy Tikonovich Krasilnikov. "The effect of new tank mixtures and herbicide compositions on economically useful indicators of soy". Agrarian Scientific Journal, n. 2 (19 febbraio 2020): 16–23. http://dx.doi.org/10.28983/asj.y2020i2pp16-23.
Testo completoAbstract (sommario):
The method of two-way analysis of variance in three field experiments in the conditions of the Right Bank of the Saratov Region studied the effect of four herbicides, two new tank mixtures and two new herbicide compositions on grain yield, number of plants per square meter, number of beans per plant, number of grains per plant, plant mass, the mass of beans from the plant, the mass of grain from the plant, the mass of 1000 grains, the protein content in the grain, the height of the plant, the height of attachment of the lower bean. The effectiveness of the herbicides was as follows: frontier optima - 72.5%, pulsar - 26.5%, gezagard - 71.2%, galaxy top - 11.7%, tank mixture frontier optima + gezagard - 86.4%, tank mixture pulsar + galaxy top - 23.0%, composition frontier optima + galaxy top - 73.8%, and composition gezagard + galaxy top - 85.1%. It was established a significant advantage in grain yield of only one new tank mixture of herbicides frontier optima + gezagard and two new compositions of herbicides frontier optima + galaxy top and gezagard + galaxy top. In the case of application of a tank mixture of herbicides, the frontier optima + hezagard yields of soybean grain significantly increased compared with the control by 377.0%, compared with herbicides the frontier optima and hezagard - by 154.0%. After the application of the herbicidal composition, the frontier optima + galaxi top soybean grain yield significantly increased compared with the control by 293.3%, compared with the herbicide frontier optima - by 120.1%, compared with the herbicide galaxy top - by 139.3%. After application of the hezagard + galaxy top herbicide composition, the soybean grain yield significantly increased compared with the control by 294.3%, compared with the hezagard herbicide - by 121.7%, compared with the galaxy top herbicide - by 141.1%.
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Demidova, V. N., T. I. Smetanina e M. A. Kuznetsova. "Reduction of Herbicidal Toxicoses on Plants Using Berkana and Izabion Organomineral Fertilizers". IOP Conference Series: Earth and Environmental Science 901, n. 1 (1 novembre 2021): 012071. http://dx.doi.org/10.1088/1755-1315/901/1/012071.
Testo completoAbstract (sommario):
Abstract Today herbicidal treatments become an obligatory component of agrotechnical activities required for plant cultivation. At the same time, being biologically active compounds, herbicides may negatively influence on plants during crop rotation. In this study the experimental data confirmed the negative effect of a metribuzin-based herbicide applied on potato towards the next crops (cucumber and lentil). Treatment of these crops with amino acid-based bioorganic fertilizers (Berkana and Izabion) in a seedling stage reduced the manifestations of the negative aftereffect of the herbicidal stress on the tested plants.
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Wang, Pei, Hui Li, Weidong Jia, Yin Chen e Roland Gerhards. "A Fluorescence Sensor Capable of Real-Time Herbicide Effect Monitoring in Greenhouses and the Field". Sensors 18, n. 11 (5 novembre 2018): 3771. http://dx.doi.org/10.3390/s18113771.
Testo completoAbstract (sommario):
Herbicide resistant weeds need to be identified early so that yield loss can be avoided by applying proper field management strategies. A novel chlorophyll-fluorescence-imaging sensor has been developed to conduct real-time herbicide effect evaluation. In this research, greenhouse and field experiments were conducted to calibrate the capability of the sensor in monitoring herbicide effects on different biotypes of two grass weeds (Alopecurus myosuroides, Apera spica-venti) in southwestern Germany. Herbicides with different modes of action were applied for the effect monitoring. Chlorophyll fluorescence yield of the plants was measured 3–15 days after treatment (DAT) using the new fluorescence sensor. Visual assessment of the weeds was carried out on 21 DAT. The results showed that the maximal PS II quantum yield (Fv/Fm) of herbicide sensitive weeds was significantly lower than the values of resistant populations in 5 DAT. The new technology was capable of quickly identifying the herbicide’s effect on plants. It can be used to optimize management strategies to control herbicide resistant weeds.
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Gettys, Lyn A., e William T. Haller. "Effect of Herbicide-Treated Irrigation Water on Four Vegetables". Weed Technology 26, n. 2 (giugno 2012): 272–78. http://dx.doi.org/10.1614/wt-d-11-00120.1.
Testo completoAbstract (sommario):
Bodies of water that are treated with herbicides for aquatic weed control are often used as a source of irrigation water by landowners near the water body, but there is little information regarding the effects of experimental aquatic herbicides on common garden plants. Therefore, the goal of these experiments was to identify phytotoxicity of four herbicides on vegetables frequently cultivated by home gardeners. Sweet pepper, zucchini, tomato, and bush bean were irrigated with water containing bispyribac-sodium, quinclorac, topramezone, and trifloxysulfuron-sodium to identify the herbicide concentrations that damage these garden vegetables. Experiments were conducted during 2009 and repeated in 2010. Plants were irrigated four times during an 11-d period with the equivalent of 1.27 cm of treated water during each irrigation, then irrigated with well water until they were harvested 41 d after the first herbicide treatment. Values of the concentration of herbicide expected to reduce treated plants by 10% compared with control plants (EC10) were calculated from components of nonlinear regression. Analysis of visual quality and dry weight data revealed that bush bean was the most sensitive of the vegetable plants to bispyribac-sodium, trifloxysulfuron-sodium, and topramezone, whereas the species most sensitive to quinclorac was zucchini. Exposure of bush bean to 7.1, 0.9, and 1.2 parts per billion (ppb) of bispyribac-sodium, trifloxysulfuron-sodium, and topramezone, respectively, would be expected to cause 10% reductions compared with control plants, whereas exposure of zucchini to as little as 11.0 ppb of quinclorac would be expected to cause a 10% reduction in dry weight.
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Calkins, James B., Bert T. Swanson e Debra L. Newman. "Weed Control Strategies for Field Grown Herbaceous Perennials". Journal of Environmental Horticulture 14, n. 4 (1 dicembre 1996): 221–27. http://dx.doi.org/10.24266/0738-2898-14.4.221.
Testo completoAbstract (sommario):
Abstract Fourteen herbicides or herbicide combinations, wood chip mulch, chipped rubber tire mulch, and newspaper mulch were evaluated for weed control efficacy and phytotoxicity using 12 species of herbaceous perennials under field growing conditions. The effect of herbicide application time was monitored by applying herbicides to dormant and actively growing plants. Herbicide and mulch treatments were compared to weeded and non-weeded controls. Herbicide phytotoxicity was dependent on age and species of herbaceous perennial and time of herbicide application. Herbicide injury was generally greater for young plants compared to established plants and phytotoxicity was usually reduced when herbicides were applied to dormant rather than actively growing plants. Injury was sometimes greater when herbicides were applied in early spring compared to applications made after complete herbaceous perennial emergence. Injury to young shoots that had emerged prior to the earliest possible time that herbicides could be applied in the spring was probably involved. Applying herbicides in the fall may avoid such injury. Mulching field grown perennials with wood chips provided the most effective weed control and often the best quality plants. With the exceptions of Hemerocallis ‘After Dark’ and Phlox maculata ‘Omega’, the herbaceous perennials evaluated were tolerant of most of the herbicides applied. Several herbicides, including Balan 2.5G at 3.36 kg ai/ha (3.0 lb ai/A), Snapshot 80DF at 4.48 kg ai/ha (4.0 lb ai/A), and Stomp 60WDG at 4.48 kg ai/ha (4.0 lb ai/A), demonstrated potential for weed control in herbaceous perennial production systems and landscape plantings. Goal 1.6EC at 1.68 kg ai/ha (1.5 lb ai/A) and Ronstar 50WP at 3.92 kg ai/ha (3.5 lb ai/A) were often phytotoxic when applied to herbaceous perennials.
Tesi sul tema "Plants, Effect of herbicides on"
1
Bevilaqua, Natalia da Cunha. "Dinâmica e ação do nicosulfuron em híbridos de milho /". Botucatu, 2019. http://hdl.handle.net/11449/181829.
Testo completoAbstract (sommario):
Orientador: Caio Antonio CarbonariBanca: Edivaldo Domingues Velini
Banca: Natália Corniani
Resumo: O herbicida nicosulfuron se destaca entre os principais utilizados em pós-emergência na cultura do milho. Dentre as tecnologias disponíveis no mercado, alguns híbridos podem ser considerados tolerantes ao nicosulfuron, e essa sensibilidade diferencial está relacionada com o ambiente, o estádio de desenvolvimento da planta e a dose de herbicida utilizada. A seletividade de herbicidas é geralmente determinada em função da fitointoxicação e do efeito do produto nas características morfológicas e fisiológicas das plantas. De modo que o objetivo do trabalho foi determinar a sensibilidade de híbridos de milho ao herbicida nicosulfuron por meio de marcadores bioquímicos. O primeiro experimento foi conduzido em casa-de-vegetação com delineamento experimental inteiramente casualizado com 4 repetições em esquema fatorial 4 x 2 (híbridos x doses), o herbicida foi aplicado nas doses 0 e 120 g i.a. ha-1 quando as plantas se encontravam no estádio fenológico V3. Foram realizadas avaliações da taxa de transporte de elétrons (ETR), fitointoxicação e altura aos 1, 3, 7 e 14 dias após a aplicação (DAA). Aos 14 DAA as plantas foram coletadas para determinação da massa seca. Dentre os híbridos utilizados selecionou-se o mais sensível e o mais tolerante para a realização de análises de determinação dos teores do ácido aminobutírico, e dos aminoácidos valina, leucina e isoleucina, nesses mesmos períodos de avaliação. O segundo experimento foi disposto em delineamento inteiramente casualizado com 5... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Nicosulfuron stands out among the principal post-emergent herbicides used in the maize crop. Among the commercial technologies available, there are some hybrids considered tolerant to this molecule and can present a differential sensitivity, process which is related to the environment, growth stage and herbicide dose. The objective of the study was to determine the sensitivity of corn hybrids to the herbicide nicosulfuron by means of biochemical markers. The first experiment was carried out under greenhouse conditions in a completely randomized design with four replications in a factorial scheme 4 x 2 (hybrids x doses). The herbicide was applied at 0 and 120 g a.i. ha-1, when the plants were in the V3 stage. Electron transport rate (ETR), phytointoxication and plant height were evaluated at 1, 3, 7 and 14 days after treatment (DAT). Plants were collected at 14 DAT to determine its dry weight. The most sensitive and tolerant hybrids were selected to determinate the content of 2-aminobutyric acid and valine, leucine and isoleucine amino acids, in the same evaluation period. The second experiment was arranged in a completely randomized design with five replications in a factorial scheme 8 x 2 (hybrids x doses), the nicosulfuron was applied at 0 and 120 g a.i. ha-1. The experiment was conducted in different periods, for V2 and V6 maize growing stage. One day after the herbicide application, the plants were collected to determine the content of nicosulfuron, 2-aminobutyric and quinic acid, as well as valine, leucine and isoleucine amino acids. During the experiment, the ETR was evaluated at 1, 7, 10, 14, 21 and 28 DAT, and the variables plant height and phytointoxication at 7, 14, 21 and 28 DAT. At 7 DAT the chlorophyll content was determined. Plants were collected at 28 DAT to determine the shoot dry weight. In the first experiment, the collection of the plants one day after application was considered the ...
Mestre
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Castro, Edicarlos Batista de [UNESP]. "Dinâmica de glyphosate em plantas de eucalipto". Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/131956.
Testo completoAbstract (sommario):
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000853172.pdf: 668118 bytes, checksum: 6bb014fda576f413445f741abae4b6a9 (MD5)O eucalipto é a espécie florestal mais utilizada em reflorestamento no país, em virtude do rápido crescimento das plantas, condições climáticas e tecnologias desenvolvidas. Porém, a interferência das plantas daninhas causa grandes prejuízos, decréscimo quantitativo e qualitativo da produção do eucalipto. Entre as possibilidades de manejo de plantas daninhas, o método químico é o mais utilizado, porém, poucos são os herbicidas registrados para a cultura do eucalipto, entre os quais o glyphosate é o mais usado por controlar um grande número de espécies. Existem poucos trabalhos a respeito dos efeitos diretos e indiretos do glyphosate nesta espécie florestal. Neste trabalho, clones de eucalipto urograndis foram submetidos ao contato direto com o glyphosate e indireto por meio de aplicação sobre plantas de Brachiaria decumbens, visando caracterizar o movimento do herbicida, exsudação radicular e seus efeitos na planta. Foram realizadas avaliações de intoxicação visual do eucalipto aos 7, 14 e 21 DAA e da massa da matéria seca das plantas aos 21 DAA. Também foram realizadas quantificações por cromatografia líquida de alta eficiência e espectrometria de massas (LC-MS/MS) em diferentes partes das plantas (superior e inferior) dos seguintes compostos: glyphosate, ácido amimetilfofônico (AMPA), ácido chiquímico, chiquimato-3-fosfato, fenilalanina, tirosina e triptofano. O glyphosate foi detectado nas plantas de eucalipto para os tratamentos com a aplicação direta e indireta do herbicida e houve translocação para os locais que não foram atingidos na aplicação, mesmo quando aplicado sobre a B. decumbens, entretanto o AMPA não foi. A presença de glyphosate nas plantas influenciou na alteração dos níveis de ácido chiquímico, fenilalanina, tirosina, triptofano e chiquimato-3-fosfato, além de causar níveis de intoxicação nas plantas de eucalipto e redução de ...
Eucalyptus is the most used forest species in reforestation in the country due to the rapid growth of plants, climatic conditions and developed technologies. However, interference by the weeds cause major damage, the quantitative and qualitative decrease in production of eucalyptus. Among the weed management possibilities, the chemical method is the most used, however, there are few herbicides registered for eucalyptus cultivation, in which glyphosate is most commonly used to control a large number of species. There are few studies regarding the direct and indirect effects of the glyphosate on this forest species. In this paper, Eucalyptus urograndis clones were subjected to direct contact with glyphosate and indirectly through application on Brachiaria decumbens plants, aiming to characterize the movement of the herbicide, root exudation and its effects on the plant. Visual evaluations were carried out through eucalyptus phytointoxication at 7, 14 and 21 DAA and of the dry mass of the plants at 21 DAA. Also, measurements were made on different parts of plants (top and bottom) of the following compounds by high-performance liquid chromatography and mass spectrometry (LC-MS / MS): glyphosate, aminomethylphosphonic acid (AMPA), shikimic acid, shikimate-3-phosphate, phenylalanine, tyrosine and tryptophan. Glyphosate was detected in eucalyptus plants for treatments with the direct and indirect application of herbicide and there was a translocation to sites that were not attain in the application, even when applied to the B. decumbens, however the AMPA was not. The presence of glyphosate on plants, influenced the change in the shikimic acid levels, phenylalanine, tyrosine, tryptophan, and shikimate- 3-phosphate, apart from causing intoxication in eucalyptus plants and reduction of dry mass. Glyphosate was detected in eucalyptus plants after application on the plants of B decumbens with low intoxicication ...
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Castro, Edicarlos Batista de 1987. "Dinâmica de glyphosate em plantas de eucalipto /". Botucatu, 2015. http://hdl.handle.net/11449/131956.
Testo completoAbstract (sommario):
Orientador: Caio Antonio CarbonariBanca: Edivaldo Domingues Velini
Banca: Leonardo David Tuffi Santos
Resumo: O eucalipto é a espécie florestal mais utilizada em reflorestamento no país, em virtude do rápido crescimento das plantas, condições climáticas e tecnologias desenvolvidas. Porém, a interferência das plantas daninhas causa grandes prejuízos, decréscimo quantitativo e qualitativo da produção do eucalipto. Entre as possibilidades de manejo de plantas daninhas, o método químico é o mais utilizado, porém, poucos são os herbicidas registrados para a cultura do eucalipto, entre os quais o glyphosate é o mais usado por controlar um grande número de espécies. Existem poucos trabalhos a respeito dos efeitos diretos e indiretos do glyphosate nesta espécie florestal. Neste trabalho, clones de eucalipto urograndis foram submetidos ao contato direto com o glyphosate e indireto por meio de aplicação sobre plantas de Brachiaria decumbens, visando caracterizar o movimento do herbicida, exsudação radicular e seus efeitos na planta. Foram realizadas avaliações de intoxicação visual do eucalipto aos 7, 14 e 21 DAA e da massa da matéria seca das plantas aos 21 DAA. Também foram realizadas quantificações por cromatografia líquida de alta eficiência e espectrometria de massas (LC-MS/MS) em diferentes partes das plantas (superior e inferior) dos seguintes compostos: glyphosate, ácido amimetilfofônico (AMPA), ácido chiquímico, chiquimato-3-fosfato, fenilalanina, tirosina e triptofano. O glyphosate foi detectado nas plantas de eucalipto para os tratamentos com a aplicação direta e indireta do herbicida e houve translocação para os locais que não foram atingidos na aplicação, mesmo quando aplicado sobre a B. decumbens, entretanto o AMPA não foi. A presença de glyphosate nas plantas influenciou na alteração dos níveis de ácido chiquímico, fenilalanina, tirosina, triptofano e chiquimato-3-fosfato, além de causar níveis de intoxicação nas plantas de eucalipto e redução de ...
Abstract: Eucalyptus is the most used forest species in reforestation in the country due to the rapid growth of plants, climatic conditions and developed technologies. However, interference by the weeds cause major damage, the quantitative and qualitative decrease in production of eucalyptus. Among the weed management possibilities, the chemical method is the most used, however, there are few herbicides registered for eucalyptus cultivation, in which glyphosate is most commonly used to control a large number of species. There are few studies regarding the direct and indirect effects of the glyphosate on this forest species. In this paper, Eucalyptus urograndis clones were subjected to direct contact with glyphosate and indirectly through application on Brachiaria decumbens plants, aiming to characterize the movement of the herbicide, root exudation and its effects on the plant. Visual evaluations were carried out through eucalyptus phytointoxication at 7, 14 and 21 DAA and of the dry mass of the plants at 21 DAA. Also, measurements were made on different parts of plants (top and bottom) of the following compounds by high-performance liquid chromatography and mass spectrometry (LC-MS / MS): glyphosate, aminomethylphosphonic acid (AMPA), shikimic acid, shikimate-3-phosphate, phenylalanine, tyrosine and tryptophan. Glyphosate was detected in eucalyptus plants for treatments with the direct and indirect application of herbicide and there was a translocation to sites that were not attain in the application, even when applied to the B. decumbens, however the AMPA was not. The presence of glyphosate on plants, influenced the change in the shikimic acid levels, phenylalanine, tyrosine, tryptophan, and shikimate- 3-phosphate, apart from causing intoxication in eucalyptus plants and reduction of dry mass. Glyphosate was detected in eucalyptus plants after application on the plants of B decumbens with low intoxicication ...
Mestre
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Silva, Ferdinando Marcos Lima [UNESP]. "Hormesis de herbicidas em soja". Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/110940.
Testo completoAbstract (sommario):
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000791298.pdf: 1255629 bytes, checksum: 167ceaa2fd11583895b9a2aee9dab019 (MD5)O efeito benéfico de subdoses de substâncias tóxicas é conhecido há muito tempo e este fenômeno é chamado de hormesis. Em agricultura, muitos são os casos de herbicidas que em doses normais causam severas injurias nas plantas, mas que em doses muito baixas promovem o crescimento de estruturas das plantas ou promovem outros efeitos benéficos, como aumento do teor de proteína em plantas. Objetivou-se com este trabalho avaliar o efeito de hormesis dos herbicidas glyphosate, amicarbazone, mesotrione, imazapic e carfentrazone em soja, além de explorar se o efeito de hormesis na soja é afetado por um pré-tratamento com baixas doses de glyphosate e mais tarde exposta as mesmas doses ou doses maiores. Para isso, três experimentos distintos foram conduzidos, sendo que no primeiro, sete doses do herbicida glyphosate (0; 1,8; 3,6; 7,2; 36; 180 e 720 g e.a.ha-1 ) foram aplicadas sobre as plantas de soja e avaliadas quanto à taxa de transporte de elétrons (ETR), acúmulo de compostos químicos alterados em função da ação do glyphosate (ácido chiquímico, ácido benzoico, ácido salicílico, AMPA, fenilalanina, tirosina e triptofano) e massa de matéria seca das plantas. No segundo experimento, foi feito um pré-tratamento das plantas com subdoses do glyphosate (0; 1,8; 3,6 e 7,2 g e.a. ha-1 ) no estádio V2 e 14 dias após esta aplicação, as plantas receberam uma segunda aplicação de diferentes doses do glyphosate (0; 1,8; 3,6; 7,2; 36; 180 e 720 g e.a. ha-1 ) e posteriormente avaliadas quanto ao acúmulo de massa de matéria seca e ácido chiquímico. No terceiro experimento, foram testadas uma completa curva de dose-resposta dos herbicidas amicarbazone, ...
The beneficial effect of low doses of toxic substances is known a long time and this phenomenon is called hormesis. In agriculture, there are many cases of herbicides that in normal rates cause severe injuries in plants, but in very low doses promote the growth of plant structures or other beneficial effect such as increase in the protein content in plants. The objective of this study was to evaluate the effect of hormesis of glyphosate, amicarbazone, mesotrione, imazapic and carfentrazone in soybean, in addition to exploring if the effect of hormesis in soybeans is affected by a pretreatment with low doses of glyphosate and later expose to the same doses or higher. For this, three separate experiments were carried out, and on the first one seven doses of glyphosate (0; 1.8; 3.6; 7.2; 36; 180 and 720 g a.e.ha-1 ) were applied to the soybean plants and evaluated the electron transport rate (ETR), the chemical compounds resulting from the action of glyphosate (shikimic acid, benzoic acid, salicylic acid, AMPA , phenylalanine, tyrosine and tryptophan) and hormesis effect on the dry weight of plants. The second experiment was made a pretreatment of soybean plants with low doses of glyphosate (0; 1.8; 3.6 and 7.2 g a.e.ha-1) in the V2 stage and 14 days later the plants received a second application of different doses of glyphosate (0; 1.8; 3.6; 7.2; 36; 180 e 720 g a.e.ha-1 ) and subsequently evaluated the dry weight of plants and shikimic acid. In the third experiment, was tested a full dose-response of the herbicides amicarbazone, mesotrione, imazapic and carfentrazone on soybean plants and evaluated the ETR and dry weight. The results indicated that at low doses glyphosate stimulated ETR and increased biomass. The compounds from shikimic acid pathway such as benzoic and salicylic acids had respective increases of 203 and 170% in the dose of 3.6 g a.e. ha-1of glyphosate and the amino ...
5
Silva, Breno Araguaia Souza [UNESP]. "Influência de diferentes períodos de chuva após a aplicação de Clethodim, Quizalofope - P- Metilico e Haloxifope em pós emergência no controle de plantas daninhas". Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/113795.
Testo completoAbstract (sommario):
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000806747.pdf: 942149 bytes, checksum: 75e0218de7b7a904e05815a10bd22002 (MD5)O trabalho teve por objetivo avaliar a influência de diferentes intervalos de tempo de chuva após a aplicação dos herbicidas clethodim, quizalofope -p- metilico e haloxifope em pós-emergência no controle de quatro espécies de plantas daninhas: B. decumbens, B. plantaginea, Cenchrus echinatus e Zea mays na cultura da soja. O delineamento experimental adotado foi inteiramente ao acaso e os tratamentos distribuídos em esquema fatorial 3 x 6 (três herbicidas e seis intervalos de tempo de chuva), totalizando dezoito tratamentos e quatro repetições, para cada espécie de planta daninha. Quatro experimentos foram conduzidos em casa de vegetação com duas plantas por vaso, no município de Pereiras, SP. As aplicações dos herbicidas foram realizadas em horários diferentes no decorrer do dia, de modo a obter os diferentes intervalos de tempo para simulação de chuva sobre as plantas. Foram realizadas avaliações de controle aos dias 3, 7, 14, 21 e 28 dias após a aplicação (DAA) dos herbicidas. Após a aplicação dos herbicidas as plantas daninhas foram submetidas a uma lâmina de chuva de 20 mm em cinco intervalos de tempo (15, 30, 60, 120 e 240 min.) e sem chuva (tratamento herbicida controle), mais o tratamento adicional sem chuva e sem aplicação de herbicida (testemunha). Ao final de cada avaliação para cada espécie vegetal foi determinado o acúmulo de biomassa das plantas. Diante do exposto verificou-se que os intervalos de chuva interferem negativamente na ação dos herbicidas para o controle da plantas e que os herbicidas quizalofope-p-metilico e haloxifope foram os que mais se destacaram no controle das plantas.
The study aimed to evaluate the influence of different time intervals of rainfall after the application of herbicide clethodim, haloxyfope and quizalofope-p-methyl, in post-emergence control of four weed species: B. decumbens, B. plantaginea, Cenchrus echinatus and Zea mays on soybeans. The experimental design was completely randomized and treatments arranged in a factorial scheme 3 x 6 (three herbicides and six time intervals of rain), totaling eighteen treatments and four replications for each weed species. Four experiments were conducted at a greenhouse with two plants per pot in the municipality of Pereiras, SP. Herbicide applications were made at different times during the day, in order to obtain different time intervals to simulate rain on the plants. Control evaluations at days 3, 7, 14, 21 and 28, were performed after application (DAA) of herbicides. After herbicide application the weeds were submitted to a slide of rain of 20 mm in five time intervals (15, 30, 60, 120 and 240 min) and no rain (herbicide treatment control), plus an additional treatment with no rain and without herbicide (control). At the end of each assessment for each species was determined the accumulation of plant biomass. With the results above it was found that the ranges of rain negatively interferes with the action of herbicides to control plants and herbicide quizalofope-p-methyl and haloxyfope were the most outstanding in plants control.
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Krolikowski, Valquiria [UNESP]. "Comportamento morfo-fisiológico de Commelina benghalensis em resposta a herbicidas aplicados em pós-emergência". Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/124429.
Testo completoAbstract (sommario):
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000834972.pdf: 477804 bytes, checksum: 750acca241c14ddab63e55869dabb5d2 (MD5)Do gênero Commelina, as trapoerabas são consideradas plantas daninhas em todas culturas no mundo. Além de prejudicar lavouras, as trapoerabas também infestam quintas e terrenos baldios em todo o país. Dificuldades no controle de Commelina benghalensis com os herbicidas existentes estão sendo observados em campo, portanto, este trabalho teve como objetivo de avaliar o controle de C. benghalensis, após a aplicação de diferentes herbicidas em cinco estádios fenológicos. As plantas foram cultivadas em vasos de 2 L contendo substrato Bioplant e solo, sendo mantidas durante todo experimento em casa de vegetação da Universidade estadual Paulista Julio Mesquita Filho - Faculdade de Engenharia. O delineamento experimental utilizado foi inteiramente casualizado com 4 repetições, em esquema fatorial 8 x 5, ou seja 7 herbicidas em doses comerciais atrazina, carfentrazone, flumioxazin, glyphosate, metanoarseniato ácido monossódico (MSMA), nicosulfuron, paraquat e uma testemunha, aplicados em 5 estádios fenológicos ajustados à escala BBCH (duas folhas verdadeiras ou cartucho foliar não distendido - BBCH 11; três folhas verdadeiras ou cartucho foliar não distendido - BBCH 12; Primeiro caule lateral visível - BBCH 21; Dois caules laterais visíveis - BBCH 22 e início de florescimento, com vinte perfilhos - BBCH 51). Observou-se que o estádio fenológico das plantas tem influência na eficiência do controle químico. Plantas em estádios iniciais de desenvolvimento (BBCH 11 e 12) mostraram-se mais suscetíveis aos herbicidas, no entanto ocorrendo controle em sua totalidade somente com os herbicidas atrazina, carfentrazone, MSMA e paraquat. Apesar de sofrer fortes injúrias a C. beghalensis apresentou tolerância a dose aplicada nos demais tratamentos
The genus Commelina, the spiderwort are considered weeds in all cultures in the world. Besides harming crops, the spiderwort also infest farms and vacant lots across the country. Difficulties in control of Commelina benghalensis with existing herbicides are observed in the field, so this study aimed to assess the control of C. benghalensis, after application of herbicides in five stages. The plants were grown in pots containing 2 L Bioplant substrate and soil being maintained throughout the experiment in a greenhouse of the Paulista State University Julio Mesquita Filho - Faculty of Engineering. The experimental design was completely randomized with four replications in factorial 8 x 5, so 7 herbicides in recommended commercial rates (atrazine, carfentrazone, flumioxazin, glyphosate, metanoarseniato ácido monossodico (MSMA),, nicosulfuron, paraquat and a control applied 5 in phenological stages adjusted the BBCH scale (two true leaves or leaf cartridge not distended - BBCH 11, three true leaves or leaf cartridge not distended - BBCH 12; First stem visible side - BBCH 21; Two visible side stems - BBCH 22 and early flowering, with twenty tillers - BBCH 51). It was observed that the growth stage of the plants affects the efficiency of chemical control. Plants in the early stages of development (BBCH 11 and 12) were more susceptible to herbicides, however occurring control in its entirety only with atrazine herbicides, carfentrazone, MSMA and paraquat. Despite suffering heavy injuries C. beghalensis have tolerance compared of another treatments
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Anunciato, Vitor Muller 1991. "Efeitos do glyphosate no crescimento e reprodução de biótipos de digitaria insularis resistente ou suscetível a este herbicida /". Botucatu, 2018. http://hdl.handle.net/11449/153658.
Testo completoAbstract (sommario):
Orientador: Caio Antonio CarbonariBanca: Edivaldo Domingues Velini
Banca: Leandro Tropaldi
Resumo: Muito já foi e ainda vem sendo estudado sobre os efeitos clássicos de dose-resposta dos herbicidas e uma outra vertente que vem surgindo são as respostas bifásicas, que incluem hormesis, caracterizada por doses baixas de um herbicida que causa estímulo e inibição em dose elevada. Assim como o estímulo pode ser benéfico na agricultura em algumas aplicações, porem quando ocorre em plantas não alvo, o efeito de hormesis pode-se tornar um problema. Nesse trabalho foram realizados quatro experimentos. Um experimento de curva dose-resposta para biótipo resistente e suscetível de Digitaria insularis, resistente ao herbicida glyphosate, avaliando-se altura das plantas, massa fresca e seca e fitotoxicidade (%) aos 7, 14 e 21 dias após a aplicação. Houve também a repetição do mesmo, um experimento com subdosagem de glyphosate para averiguar o efeito das subdosagens no florescimento, avaliando-se o número de panículas emitidos após a aplicação dos tratamentos e o quarto experimento que foi a verificação da germinação, índice de velocidade de germinação e peso de sementes provindas do terceiro experimento. O efeito de estímulo das subdoses foram constatados em todos os experimentos sendo que diferentes faixas de doses causaram o efeito de hormesis nos biótipos de D.insularis, resistente e suscetível havendo aumento de altura, massa, peso de sementes e velocidade de germinação e diminuição do tempo necessário para emissão das inflorescências. Esses efeitos podem conceder uma grande vantag... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Currently much has been studied about the classic dose-response effects of herbicides and another aspect that is emerging are the biphasic responses, which include hormesis, a biphasic dose-response phenomenon characterized by low dose stimulation and high dose inhibition. Just as the stimulus may be beneficial in agriculture in several applications, when this stimulus occurs in non-target plants, the effect of hormesis can become a problem. In this work, a dose-response curve experiment was performed for resistant and susceptible biotypes of Digitaria insularis, resistant to the glyphosate herbicide and evaluating plant height, fresh and dry mass and phytotoxicity (%) at 7, 14 and 21 days after application. The second experiment was the repetition of the firs. An experiment with subdoses of glyphosate are performed to investigate the effect of the subdoses on flowering, evaluating the number of panicles emitted after the application of the treatments and the fourth experiment that was the verification of the germination, germination speed index and seed weight from the third experiment. The effect of subdoses stimulation was observed in all the experiments, with different dose ranges causing the stimulus in the D.insularis biotypes, resistant and susceptible, increasing height, mass, seed weight and germination speed and reduced the time required for inflorescence emission. These effects can give a great advantage to the spread of this species, helping to change the flora of weeds
Mestre
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Silva, Breno Araguaia Souza 1989. "Influência de diferentes períodos de chuva após a aplicação de Clethodim, Quizalofope - P- Metilico e Haloxifope em pós emergência no controle de plantas daninhas /". Botucatu, 2014. http://hdl.handle.net/11449/113795.
Testo completoAbstract (sommario):
Orientador: Carlos Gilberto RaetanoBanca: Marcelo Rocha Correa
Banca: Elza Alves Correa
Resumo: O trabalho teve por objetivo avaliar a influência de diferentes intervalos de tempo de chuva após a aplicação dos herbicidas clethodim, quizalofope -p- metilico e haloxifope em pós-emergência no controle de quatro espécies de plantas daninhas: B. decumbens, B. plantaginea, Cenchrus echinatus e Zea mays na cultura da soja. O delineamento experimental adotado foi inteiramente ao acaso e os tratamentos distribuídos em esquema fatorial 3 x 6 (três herbicidas e seis intervalos de tempo de chuva), totalizando dezoito tratamentos e quatro repetições, para cada espécie de planta daninha. Quatro experimentos foram conduzidos em casa de vegetação com duas plantas por vaso, no município de Pereiras, SP. As aplicações dos herbicidas foram realizadas em horários diferentes no decorrer do dia, de modo a obter os diferentes intervalos de tempo para simulação de chuva sobre as plantas. Foram realizadas avaliações de controle aos dias 3, 7, 14, 21 e 28 dias após a aplicação (DAA) dos herbicidas. Após a aplicação dos herbicidas as plantas daninhas foram submetidas a uma lâmina de chuva de 20 mm em cinco intervalos de tempo (15, 30, 60, 120 e 240 min.) e sem chuva (tratamento herbicida controle), mais o tratamento adicional sem chuva e sem aplicação de herbicida (testemunha). Ao final de cada avaliação para cada espécie vegetal foi determinado o acúmulo de biomassa das plantas. Diante do exposto verificou-se que os intervalos de chuva interferem negativamente na ação dos herbicidas para o controle da plantas e que os herbicidas quizalofope-p-metilico e haloxifope foram os que mais se destacaram no controle das plantas.
Abstract: The study aimed to evaluate the influence of different time intervals of rainfall after the application of herbicide clethodim, haloxyfope and quizalofope-p-methyl, in post-emergence control of four weed species: B. decumbens, B. plantaginea, Cenchrus echinatus and Zea mays on soybeans. The experimental design was completely randomized and treatments arranged in a factorial scheme 3 x 6 (three herbicides and six time intervals of rain), totaling eighteen treatments and four replications for each weed species. Four experiments were conducted at a greenhouse with two plants per pot in the municipality of Pereiras, SP. Herbicide applications were made at different times during the day, in order to obtain different time intervals to simulate rain on the plants. Control evaluations at days 3, 7, 14, 21 and 28, were performed after application (DAA) of herbicides. After herbicide application the weeds were submitted to a slide of rain of 20 mm in five time intervals (15, 30, 60, 120 and 240 min) and no rain (herbicide treatment control), plus an additional treatment with no rain and without herbicide (control). At the end of each assessment for each species was determined the accumulation of plant biomass. With the results above it was found that the ranges of rain negatively interferes with the action of herbicides to control plants and herbicide quizalofope-p-methyl and haloxyfope were the most outstanding in plants control.
Mestre
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Moraes, Carolina Pucci de 1989. "Controle e hormesis de glyphosate em Brachiaria decumbens /". Botucatu, 2016. http://hdl.handle.net/11449/143503.
Testo completoAbstract (sommario):
Orientador: Edivaldo Domingues VeliniBanca: Caio Atonio Carbonari
Banca: Luciano Soares de Souza
Resumo: O efeito de estímulo de uma característica biológica por baixas dosesde um composto considerado tóxico, mas que em altas doses tem efeito inibitório édenominado efeito hormesis. Estímulos de crescimento em plantas têm sido verificados apósa aplicação de subdoses de alguns herbicidas, incluindo o glyphosate. Nesse contexto, opresente trabalho teve por objetivo avaliar as respostas de crescimento de plantas deBrachiaria decumbens submetidas a diferentes doses de glyphosate. Foram realizados doisestudos em casa de vegetação, ambos em delineamento inteiramente casualizado (DIC). Noprimeiro estudo foram realizados três experimentos com seis repetições, sendo noexperimento 1 testada uma curva de dose-resposta com nove doses do herbicida glyphosate(0; 22,5; 45; 90; 180; 360; 720; 1440 e 2880 g e.a. ha-1). Nos experimentos dois e três foramaplicadas onze doses do herbicida glyphosate (0; 2,8125; 5,625; 11,25; 22,5; 45; 90; 180;360; 720 e 1440 g e.a. ha-1). No estudo 2 para a avaliação de subdoses com efeito hormesisrealizou-se quatro experimentos, em DIC com oito repetições e dois tratamentos (testemunhae dose de 11,25 g e.a. ha-1). Para ambos os estudos foram coletadas oito plantas de vasos semaplicação para a determinação da biomassa inicial dos experimentos. Nos experimentos doestudo 1 foram realizadas avaliações de fitointoxicação aos 0, 7, 14 e 21 dias após a aplicação(DAA), além da coleta de oito plantas por vaso de cada tratamento para determina... (Resumo completo, clicar acesso eletrônico abaixo)
Mestre
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Silva, Ferdinando Marcos Lima 1981. "Hormesis de herbicidas em soja /". Botucatu :, 2014. http://hdl.handle.net/11449/110940.
Testo completoAbstract (sommario):
Orientador: Edivaldo Domingues VeliniCoorientador: Stephen O.Duke
Coorientador: Franck E.Dayan
Banca: Caio Antonio Carbonari
Banca: Antonio Luiz Cerdeira
Banca: Marcelo de Almeda Silva
Banca: Sidnei Douglas Cavalieri
Resumo: O efeito benéfico de subdoses de substâncias tóxicas é conhecido há muito tempo e este fenômeno é chamado de hormesis. Em agricultura, muitos são os casos de herbicidas que em doses normais causam severas injurias nas plantas, mas que em doses muito baixas promovem o crescimento de estruturas das plantas ou promovem outros efeitos benéficos, como aumento do teor de proteína em plantas. Objetivou-se com este trabalho avaliar o efeito de hormesis dos herbicidas glyphosate, amicarbazone, mesotrione, imazapic e carfentrazone em soja, além de explorar se o efeito de hormesis na soja é afetado por um pré-tratamento com baixas doses de glyphosate e mais tarde exposta as mesmas doses ou doses maiores. Para isso, três experimentos distintos foram conduzidos, sendo que no primeiro, sete doses do herbicida glyphosate (0; 1,8; 3,6; 7,2; 36; 180 e 720 g e.a.ha-1 ) foram aplicadas sobre as plantas de soja e avaliadas quanto à taxa de transporte de elétrons (ETR), acúmulo de compostos químicos alterados em função da ação do glyphosate (ácido chiquímico, ácido benzoico, ácido salicílico, AMPA, fenilalanina, tirosina e triptofano) e massa de matéria seca das plantas. No segundo experimento, foi feito um pré-tratamento das plantas com subdoses do glyphosate (0; 1,8; 3,6 e 7,2 g e.a. ha-1 ) no estádio V2 e 14 dias após esta aplicação, as plantas receberam uma segunda aplicação de diferentes doses do glyphosate (0; 1,8; 3,6; 7,2; 36; 180 e 720 g e.a. ha-1 ) e posteriormente avaliadas quanto ao acúmulo de massa de matéria seca e ácido chiquímico. No terceiro experimento, foram testadas uma completa curva de dose-resposta dos herbicidas amicarbazone, ...
Abstract: The beneficial effect of low doses of toxic substances is known a long time and this phenomenon is called hormesis. In agriculture, there are many cases of herbicides that in normal rates cause severe injuries in plants, but in very low doses promote the growth of plant structures or other beneficial effect such as increase in the protein content in plants. The objective of this study was to evaluate the effect of hormesis of glyphosate, amicarbazone, mesotrione, imazapic and carfentrazone in soybean, in addition to exploring if the effect of hormesis in soybeans is affected by a pretreatment with low doses of glyphosate and later expose to the same doses or higher. For this, three separate experiments were carried out, and on the first one seven doses of glyphosate (0; 1.8; 3.6; 7.2; 36; 180 and 720 g a.e.ha-1 ) were applied to the soybean plants and evaluated the electron transport rate (ETR), the chemical compounds resulting from the action of glyphosate (shikimic acid, benzoic acid, salicylic acid, AMPA , phenylalanine, tyrosine and tryptophan) and hormesis effect on the dry weight of plants. The second experiment was made a pretreatment of soybean plants with low doses of glyphosate (0; 1.8; 3.6 and 7.2 g a.e.ha-1) in the V2 stage and 14 days later the plants received a second application of different doses of glyphosate (0; 1.8; 3.6; 7.2; 36; 180 e 720 g a.e.ha-1 ) and subsequently evaluated the dry weight of plants and shikimic acid. In the third experiment, was tested a full dose-response of the herbicides amicarbazone, mesotrione, imazapic and carfentrazone on soybean plants and evaluated the ETR and dry weight. The results indicated that at low doses glyphosate stimulated ETR and increased biomass. The compounds from shikimic acid pathway such as benzoic and salicylic acids had respective increases of 203 and 170% in the dose of 3.6 g a.e. ha-1of glyphosate and the amino ...
Doutor
Libri sul tema "Plants, Effect of herbicides on"
1
D, Dodge A., e Society for Experimental Biology (Great Britain). Plant Metabolism Group., a cura di. Herbicides and plant metabolism. Cambridge: Cambridge University Press, 1989.
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2
R, Baker N., e Percival M. P, a cura di. Herbicides. Amsterdam: Elsevier, 1991.
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3
Herbicides and plant physiology. London: Chapman & Hall, 1992.
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4
Cobb, Andrew. Herbicides and plant physiology. 2a ed. Ames, Iowa: Blackwell Pub., 2010.
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5
P, Sharma M. Recognizing Herbicide Action & Injury. 2a ed. Vegreville, Alt: Alberta Environmental Centre, 1986.
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Voskoboĭnikov, V. V. Gerbit͡s︡idy v drevesnykh i plodovo-i͡a︡godnykh nasazhdenii͡a︡kh Donbassa. Kiev: Nauk. dumka, 1991.
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de, Prado R., Jorŕin J, García-Torres L e International Symposium on Weed and Crop Resistance to Herbicides (1995 : Córdoba, Spain), a cura di. Weed and crop resistance to herbicides. Dordrecht: Kluwer Academic, 1997.
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H, Reade John P., a cura di. Herbicides and plant physiology. 2a ed. Ames, Iowa: Blackwell Pub., 2010.
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Mallory-Smith, Carol. Herbicide-resistant weeds and their management. [Moscow, Idaho]: University of Idaho Cooperativae Extension System, 1993.
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Mallory-Smith, Carol. Herbicide-resistant weeds and their management. [Moscow, Idaho]: University of Idaho Cooperativae Extension System, 1993.
Cerca il testo completoCapitoli di libri sul tema "Plants, Effect of herbicides on"
1
Strandberg, Beate, Céline Boutin, Solvejg K. Mathiassen, Christian Damgaard, Yoko L. Dupont, David J. Carpenter e Per Kudsk. "Effects of Herbicides on Non-Target Terrestrial Plants". In ACS Symposium Series, 149–66. Washington, DC: American Chemical Society, 2017. http://dx.doi.org/10.1021/bk-2017-1249.ch011.
Testo completo
2
Sławomir, Stankowski, e Maciorowski Robert. "Successive Effect of Herbicides on Triticale Seed Germination and Plant Growth". In Triticale: Today and Tomorrow, 743–47. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-0329-6_98.
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3
Monteiro, A., I. Moreira e E. Sousa. "Effect of prior common reed (Phragmites australis) cutting on herbicide efficacy". In Biology, Ecology and Management of Aquatic Plants, 305–8. Dordrecht: Springer Netherlands, 1999. http://dx.doi.org/10.1007/978-94-017-0922-4_44.
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Matoušková, Martina, Jan Nauš e Marie Flašarová. "Response of Maize Plants to Pre-Emergence Application of Herbicides Monitored by Fast Chlorophyll Fluorescence Induction". In Photosynthesis: Mechanisms and Effects, 3893–96. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-3953-3_908.
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Rodrigues, G. C., M. A. K. Jansen, M. E. Van den Noort e J. J. S. Van Rensen. "Effects of UV-B Radiation on Photosynthesis in Leaves of Chenopodium Album Plants Resistant or Sensitive to Triazine Herbicides". In Photosynthesis: Mechanisms and Effects, 2401–4. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-3953-3_564.
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Piñol, R., e E. Simón. "Protective effects of brassinosteroids against herbicides". In Brassinosteroids: A Class of Plant Hormone, 309–44. Dordrecht: Springer Netherlands, 2010. http://dx.doi.org/10.1007/978-94-007-0189-2_11.
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Garcia, I., M. Rodgers, R. Pépin, Tzung-Fu Hsieh e M. Matringe. "Plant P-Hydroxyphenylpyruvate Dioxygenase: A Target for New Bleaching Herbicides". In Photosynthesis: Mechanisms and Effects, 3861–64. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-3953-3_900.
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O’Keefe, Daniel P., James A. Romesser e Kenneth J. Leto. "Plant and Bacterial Cytochromes P-450: Involvement in Herbicide Metabolism". In Phytochemical Effects of Environmental Compounds, 151–73. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4613-1931-3_6.
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Karapetyan, N. V. "Photosynthesis and Herbicides: Effects of Pyridazinones on Chloroplast Function and Biogenesis". In Photosynthesis: Photoreactions to Plant Productivity, 181–98. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-2708-0_7.
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Pace, E., D. Esposito, M. Rizzuto, L. Pompili e MT Giardi. "3H-Leucine Incorporation in Short and Long-Term Herbicide Treatments in Variously Tolerant Higher Plants". In Photosynthesis: Mechanisms and Effects, 3881–84. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-3953-3_905.
Testo completoAtti di convegni sul tema "Plants, Effect of herbicides on"
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Timergalin, M. D., A. V. Feoktistova, T. V. Rameev, S. P. Chetverikov e Z. R. Sultangazin. "Wheat yields of herbicide treatment along with auxin-producing bacteria Pseudomonas sp. DА1.2". In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.246.
Testo completoAbstract (sommario):
The effect of the identified auxin-producing strain of bacteria on wheat plants when treated with the herbicides Chistalan and Nanometh in the field was studied. The ability of bacterial treatment to increase wheat yield under herbicidal stress due to the positive effect of bacteria on plant growth and development at early stages of development is shown.
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Kudryavtsev, N. A., L. A. Zaitseva e Z. K. Kurbanova. "ECOLOGIZATION OF MEASURES A PROTECTIVE – STIMULATING AND HERBICIDES EFFECTS ON SEDS AND CROPS OF FLAX AND OTHER PLANTS". In STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS. DSTU-PRINT, 2020. http://dx.doi.org/10.23947/interagro.2020.1.626-629.
Testo completoAbstract (sommario):
When testing a protective – stimulating and herbicides means acceptable to the technology of cultivation flax, it is established that the growth regulators – Lostor and Artaphit – effective against bacterioosis (Bacillus macerans Schr.), аnthracnose (Colletotrichum lini Manns et Bolley), mottle /ozoniose/ (Ozonium vinogradovi Kudr.) flax and contribute increasing the yild of flax and hemp. New biological product developed by us (mix the inoculum of smut /uroczistose/ qack grass (Urocystis agropyri /P./S.) and fragrant rust (Puccinia suaveollens /Pers./) bristly Thistle – reduced contamination of crops called weeds of flax and hemp.
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Feoktistova, A. V., M. D. Timergalin, T. V. Rameev e S. P. Chetverikov. "The role of auxin-producing bacteria in the formation of a growth response in wheat plants under herbicidal stress". In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.073.
Testo completoAbstract (sommario):
The paper presents the results of the effect of treatment with bacteria on the growth and hormonal balance of wheat plants with simultaneous exposure to the herbicide Chistalan. It is shown that herbicide stress is leveled by bacteria.
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Bakaeva, M. D., S. P. Chetverikov, D. V. Chetverikova e A. A. Kendzhieva. "Promising microorganisms for coping herbicide stress in plants". In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.032.
Testo completoAbstract (sommario):
Herbicide-resistant strains of Pseudomonas and Achromobacter have been isolated. Theу are diazotrophic, can mobilize phosphorus from insoluble compounds and synthesize phytohormones in the presence of herbicides.
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Mandrik-Litvinkovich, M. N., P. I. Orlovskaya, P. M. Kislushko e E. I. Kalamiyets. "Microbial preparation for soil bioremediation and crop yield increase". In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.161.
Testo completoAbstract (sommario):
A microbial preparation based on bacteria with enzymatic, antimicrobial and growth-stimulating activities effectively reduces residual amounts of herbicides of sulfonylurea series and imidazolinones and promotes productivity of agricultural crops.
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Nimaeva, O. D., E. V. Pradedova e R. K. Salyaev. "Activation of oxidative processes in isolated plastids, mitochondria and vacuoles under the action of herbicides". In IX Congress of society physiologists of plants of Russia "Plant physiology is the basis for creating plants of the future". Kazan University Press, 2019. http://dx.doi.org/10.26907/978-5-00130-204-9-2019-315.
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Raza, S., K. A. Sallam e S. L. Post. "The Effect of Crosswind Velocity on the Spray Drift of Flat Fan Nozzle". In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-12049.
Testo completoAbstract (sommario):
Abstract The objective of this research project is to eliminate the spray drift caused by crosswind. Spray drift is an important problem for the agricultural industry. Some herbicides (e.g. Dicamba) can cause serious damage if it drifts to nearby crops that are not genetically modified to withstand those herbicides. Our hypothesis is that the nozzle geometry and the injection angle can be actively/passively controlled to compensate for the crosswind velocity and effectively deliver the herbicides to the target area. The measurements include the breakup regime transitions, the droplet sizes, and the droplets trajectory as function of the wind speed and the injection angle. The current results show that the crosswind modifies the primary breakup mechanism from sheet breakup regime (i.e. thinning and fragmentation of the liquid sheet into ligaments) to bag breakup regime (i.e. the formation bags along the downstream side of liquid sheet) resulting in smaller drop sizes and an increased drift flux. Techniques to eliminate the bag breakup regime are presented.
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Kalabashkina, E. V., V. A. Tsymbalova, S. V. Uldina, L. P. Abramkina, A. V. Mednov, N. A. Yashina e L. I. Mavlutova. "Anti-slag herbicides on Agata spring wheat". In Растениеводство и луговодство. Тимирязевская сельскохозяйственная академия, 2020. http://dx.doi.org/10.26897/978-5-9675-1762-4-2020-172.
Testo completoAbstract (sommario):
results of research on the effect of anti-slag herbicides: Axial, CE, Verdict, VDG, Lastik exstra, EС, Pallas 45, MD on spring wheat Agata in the Moscow region are presented. The research was performed in 2019 on the fields of the Nemchinovka research center. Infestation was represented by two types of monocotyledonous weeds from the Bluegrass family (Grasses): annual bluegrass (Póa Annua) and barn grass (Echinóchloa crus-gálli). The use of anti-slag herbicides reduces the number of weeds in the experiment and their air-dry mass. Herbicide treatment increased the wheat grain yield by 1.19-1.67 t / ha and increased protein by 0.5-3.3%.
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Cristea, Nicolae Ionut, Valentina Andreea Petre, Iuliana Paun e Florentina Laura Chiriac. "ASSESSMENT OF SIX HERBICIDES FROM VARIOUS CLASSES IN PLANTS BODY PARTS BY A NOVEL GC-MS/MS METHOD". In International Symposium "The Environment and the Industry". National Research and Development institute for Industrial Ecology, 2022. http://dx.doi.org/10.21698/simi.2022.ab25.
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Gulueva, L. R. "The unit for the trunk processing of seedlings". In Agrobiotechnology-2021. Publishing house of RGAU - MSHA, 2021. http://dx.doi.org/10.26897/978-5-9675-1855-3-2021-14.
Testo completoAbstract (sommario):
The article presents the materials of scientific developments on the local introduction of herbicides into the trunk zone of seedlings based on the cultivator KCHG-2.4, which replaces manual weeding of rows of plants, excluding the ingress of herbicide on the leaf-stem apparatus. The unit allows you to save stubble up to 51%, which reliably protects the soil from water erosion when destroying weed vegetation up to 94%.
Rapporti di organizzazioni sul tema "Plants, Effect of herbicides on"
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Mudge, Christopher R., Kurt D. Getsinger e Benjamin P. Sperry. Simulated Herbicide Spray Retention on Floating Aquatic Plants as Affected by Carrier Volume and Adjuvant Type. U.S. Army Engineer Research and Development Center, giugno 2022. http://dx.doi.org/10.21079/11681/44540.
Testo completoAbstract (sommario):
Foliar delivery of herbicides is a common means for plant management in aquatic environments. Though this technique is decades old, little is known about vegetative spray retention relative to this application method. A more complete understanding of maximizing herbicide retention could lead to improved plant management while simultaneously decreasing pesticide load in aquatic environments. Therefore, outdoor mesocosm experiments were conducted in 2020 to evaluate the effect of adjuvant type on foliar spray retention in waterhyacinth [Eichhornia crassipes (Mart.) Solms]. Additionally, the effect of carrier volume on spray retention in waterhyacinth, waterlettuce (Pistia stratiotes L.), and giant salvinia (Salvinia molesta D.S. Mitchell) was documented. Spray deposition did not differ among the nine adjuvants tested; however, spray retention was reduced 6% to 11% when an adjuvant was excluded from the spray solution. The effect of carrier volume on spray retention in waterhyacinth, waterlettuce, and giant salvinia was also investigated. Decreases in spray retention were most sensitive to increased carrier volume in waterhyacinth, followed by giant salvinia and waterlettuce. Among species, spray retention potential, as determined by intercept estimates, was greatest in waterlettuce and giant salvinia regardless of carrier volume. Asymptotes estimates for waterhyacinth, waterlettuce, and giant salvinia were 33%, 46%, and 79% spray retention, respectively. In other words, spray retention was the lowest and remained relatively constant at these values for the high carrier volumes tested (935 and 1,870 L ha⁻¹), which were likely due to the presence of pubescence on leaves and flatter leaf architecture represented by waterlettuce and giant salvinia compared to the glabrous vertical leaves of waterhyacinth. Future research will evaluate these concepts under field condition.
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Mudge, Christopher, e Kurt Getsinger. Comparison of generic and proprietary aquatic herbicides for control of invasive vegetation; part 3 : submersed plants. Engineer Research and Development Center (U.S.), settembre 2021. http://dx.doi.org/10.21079/11681/42061.
Testo completoAbstract (sommario):
Herbicide selection is key to efficiently managing nuisance vegetation in our nation’s waterways. After selecting the active ingredient, there still remains multiple proprietary and generic products to choose from. Recent small-scale research has been conducted to compare the efficacy of these herbicides against floating and emergent species. Therefore, a series of mesocosm and growth chamber trials were conducted to evaluate subsurface applications of the following herbicides against submersed plants: diquat versus coontail (Ceratophyllum demersum L.), hydrilla (Hydrilla verticillata L.f. Royle), southern naiad (Najas guadalupensis (Sprengel) Magnus), and Eurasian watermilfoil (Myriophyllum spicatum L.); flumioxazin versus coontail, hydrilla, and Eurasian watermilfoil; and triclopyr against Eurasian watermilfoil. All active ingredients were applied at concentrations commonly used to manage these species in public waters. Visually, all herbicides within a particular active ingredient performed similarly with regard to the onset and severity of injury symptoms throughout the trials. All trials, except diquat versus Eurasian watermilfoil, resulted in no differences in efficacy among the 14 proprietary and generic herbicides tested, and all herbicides provided 43%–100% control, regardless of active ingredient and trial. Under mesocosm and growth chamber conditions, the majority of the generic and proprietary herbicides evaluated against submersed plants provided similar control.
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Mudge, Christopher, e Kurt Getsinger. Comparison of generic and proprietary aquatic herbicides for control of invasive vegetation : part 1. floating plants. Engineer Research and Development Center (U.S.), settembre 2019. http://dx.doi.org/10.21079/11681/34183.
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Mudge, Christopher R., e Kurt D. Getsinger. Comparison of Generic and Proprietary Aquatic Herbicides for Control of Invasive Vegetation : Part 2. Emergent Plants. Engineer Research and Development Center (U.S.), novembre 2021. http://dx.doi.org/10.21079/11681/39679.
Testo completoAbstract (sommario):
Aquatic herbicides are one of the most effective and widespread ways to manage nuisance vegetation in the US After the active ingredient is selected, often there are numerous proprietary and generic branded products to select from. To date, limited efforts have been made to compare the efficacy of brand name and generic herbicides head to head; therefore, at tot al of 20 mesocosm trials were conducted to evaluate various 2,4 -D, glyphosate, imazapyr, and triclopyr products against alligatorweed (Alternanthera philoxeroides (Mart.) Griseb.), southern cattail (hereafter referred to as cattail, Typha domingensis Pers.), and creeping water primrose (hereafter referred as primrose, Ludwigia peploides (Kunth) P.H. Raven). All active ingredients were applied to foliage at broadcast rates commonly used in applications to public waters. Proprietary and generic 2,4 -D, glyphosate, imazapyr, and triclopyr were efficacious and provided 39 to 99% control of alligatorweed, cattail and primrose in 19 of the 20 trials. There were no significant differences i n product performance except glyphosate vs. alligatorweed (trial 1, Rodeo vs. Roundup Custom) and glyphosate vs. cattail (trial 1, Rodeo vs. Glyphosate 5.4). These results demonstrate under small -scale conditions, the majority of the generic and proprietary herbicides provided similar control of emergent vegetation, regardless of active ingredient
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Westerdahl, Howard E., e Kurt D. Getsinger. Aquatic Plant Control Research Program: Aquatic Plant Identification and Herbicide Use Guide. Volume 2. Aquatic Plants and Susceptibility to Herbicides. Fort Belvoir, VA: Defense Technical Information Center, novembre 1988. http://dx.doi.org/10.21236/ada203243.
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Kirova, Elisaveta. Effect of Nitrogen Nutrition Source on Antioxidant Defense System of Soybean Plants Subjected to Salt Stress. "Prof. Marin Drinov" Publishing House of Bulgarian Academy of Sciences, febbraio 2020. http://dx.doi.org/10.7546/crabs.2020.02.09.
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García Victoria, Nieves, Esteban Baeza Romero, Geert Franken, Silke Hemming e Gert Vletter. Effect of high scattering lamellae on growthand photosynthesis of young tomato plants : smart materials crop experiments. Bleiswijk: Stichting Wageningen Research, Wageningen Plant Research, Business Unit Greenhouse Horticulture, 2020. http://dx.doi.org/10.18174/564877.
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Palukaitis, Peter, Amit Gal-On, Milton Zaitlin e Victor Gaba. Virus Synergy in Transgenic Plants. United States Department of Agriculture, marzo 2000. http://dx.doi.org/10.32747/2000.7573074.bard.
Testo completoAbstract (sommario):
Transgenic plants expressing viral genes offer novel means of engendering resistance to those viruses. However, some viruses interact synergistically with other viruses and it is now known that transgenic plants expressing particular genes of one virus may also mediate synergy with a second virus. Thus, our specific objectives were to (1) determine if transgenic plants resistant to one virus showed synergy with another virus; (2) determine what viral sequences were essential for synergy; and (3) determine whether one of more mechanisms were involved i synergy. This project would also enable an evaluation of the risks of synergism associated with the use of such transgenic plants. The conclusion deriving from this project are as follows: - There is more than one mechanism of synergy. - The CMV 2b gene is required for synergistic interactions. - Synergy between a potyvirus and CMV can break natural resistance limiting CMV movement. - Synergy operates at two levels - increase in virus accumulation and increase in pathology - independently of each other. - Various sequences of CMV can interact with the host to alter pathogenicity and affect virus accumulation. - The effect of synergy on CMV satellite RNA accumulatio varies in different systems. - The HC-Pro gene may only function in host plant species to induce synergy. - The HC-Pro is a host range determinant of potyviruses. - Transgenic plants expressing some viral sequences showed synergy with one or more viruses. Transgenic plants expressing CMV RNA 1, PVY NIb and the TMV 30K gene all showed synergy with at least one unrelated virus. - Transgenic plants expressing some viral sequences showed interference with the infection of unrelated viruses. Transgenic plants expressing the TMV 30K, 54K and 126K genes, the PVY NIb gene, or the CMV 3a gene all showed some level of interference with the accumulation (and in some cases the pathology) of unrelated viruses. From our observations, there are agricultural implications to the above conclusions. It is apparent that before they are released commercially, transgenic plants expressing viral sequences for resistance to one virus need to be evaluated fro two properties: - Synergism to unrelated viruses that infect the same plant. Most of these evaluations can be made in the greenhouse, and many can be predicted from the known literature of viruses known to interact with each other. In other cases, where transgenic plants are being generated from new plant species, the main corresponding viruses from the same known interacting genera (e.g., potexviruses and cucumoviruses, potyviruses and cucumoviruses, tobamoviruses and potexviruses, etc.) should be evaluated. - Inhibition or enhancement of other resistance genes. Although it is unlikely that plants to be released would be transformed with HC-Pro or 2b genes, there may be other viral genes that can affect the expression of plant genes encoding resistance to other pathogens. Therefore, transgenic plants expressing viral genes to engender pathogen-derived resistance should be evaluated against a spectrum of other pathogens, to determine whether those resistance activities are still present, have been lost, or have been enhanced!
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Miles, Gaines E., Yael Edan, F. Tom Turpin, Avshalom Grinstein, Thomas N. Jordan, Amots Hetzroni, Stephen C. Weller, Marvin M. Schreiber e Okan K. Ersoy. Expert Sensor for Site Specification Application of Agricultural Chemicals. United States Department of Agriculture, agosto 1995. http://dx.doi.org/10.32747/1995.7570567.bard.
Testo completoAbstract (sommario):
In this work multispectral reflectance images are used in conjunction with a neural network classifier for the purpose of detecting and classifying weeds under real field conditions. Multispectral reflectance images which contained different combinations of weeds and crops were taken under actual field conditions. This multispectral reflectance information was used to develop algorithms that could segment the plants from the background as well as classify them into weeds or crops. In order to segment the plants from the background the multispectrial reflectance of plants and background were studied and a relationship was derived. It was found that using a ratio of two wavelenght reflectance images (750nm and 670nm) it was possible to segment the plants from the background. Once ths was accomplished it was then possible to classify the segmented images into weed or crop by use of the neural network. The neural network developed for this work is a modification of the standard learning vector quantization algorithm. This neural network was modified by replacing the time-varying adaptation gain with a constant adaptation gain and a binary reinforcement function. This improved accuracy and training time as well as introducing several new properties such as hill climbing and momentum addition. The network was trained and tested with different wavelength combinations in order to find the best results. Finally, the results of the classifier were evaluated using a pixel based method and a block based method. In the pixel based method every single pixel is evaluated to test whether it was classified correctly or not and the best weed classification results were 81% and its associated crop classification accuracy is 57%. In the block based classification method, the image was divided into blocks and each block was evaluated to determine whether they contained weeds or not. Different block sizes and thesholds were tested. The best results for this method were 97% for a block size of 8 inches and a pixel threshold of 60. A simulation model was developed to 1) quantify the effectiveness of a site-specific sprayer, 2) evaluate influence of diffeent design parameters on efficiency of the site-specific sprayer. In each iteration of this model, infected areas (weed patches) in the field were randomly generated and the amount of required herbicides for spraying these areas were calculated. The effectiveness of the sprayer was estimated for different stain sizes, nozzle types (conic and flat), nozzle sizes and stain detection levels of the identification system. Simulation results indicated that the flat nozzle is much more effective as compared to the conic nozzle and its relative efficiency is greater for small nozzle sizes. By using a site-specific sprayer, the average ratio between the spraying areas and the stain areas is about 1.1 to 1.8 which can save up to 92% of herbicides, especially when the proportion of the stain areas is small.
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Citovsky, Vitaly, e Yedidya Gafni. Nuclear Import of the Tomato Yellow Curl Leaf Virus in Tomato Plants. United States Department of Agriculture, settembre 1994. http://dx.doi.org/10.32747/1994.7568765.bard.
Testo completoAbstract (sommario):
Tomato yellow leaf curl geminivirus (TYLCV) is a major pathogen of cultivated tomato, causing up to 100% crop loss in many parts of the world. In Israel the disease is well known and has an economic significance. In recent years viral symptoms were found in countries of the "New World" and since 1997, in Florida. Surprisingly, little is known about the molecular mechanisms of TYLCV interaction with the host plant cells. This proposal was aimed at expanding our understanding of the molecular mechanisms by which TYLCV enters the host cell nucleus. The main objective was to elucidate the TYLCV protein(s) involved in transport of the viral genomic DNA into the host cell nucleus. This goal was best served by collaboration between our laboratories one of which (V.C.) was already investigating the nuclear import of the T-DNA ofAgrobacterium tumefaciens, and the other (Y.G.) was studying the effect of TYLCV capsid protein (CP) in transgenic plants, hypothesizing its involvement in the viral nuclear entry. Three years of our collaborative work have provided signifcant data that strongly support our original hypothesis of the involvement of TYLCtr CP in viral nuclear import. Furthermore, our results have laid a foundation to study fundamental, but as yet practically unresolved, questions about the role ofthe host cell factors in the nuclear import of geminiviruses within their host plant. As a result, this research may lead to development of new approaches for plant protection based on control of TYLCV import to the host plant cell nucleus.