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1

Umeda, K., and N. Lund. "Effect of Prowl and Prefar Herbicides on Onions." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2001. http://hdl.handle.net/10150/214935.

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Significant onion height reduction was observed when Prowl (pendimethalin) and Prefar (bensulide) herbicide combinations were applied preemergence (PREE). The onions resumed growth but the height was still slightly reduced later in the growing season compared to the handweeded check and the standard herbicide treatment, Dacthal (DCPA). The onion crop stand emerged initially but later in the season, a significant crop stand reduction was observed for the higher rate of Prowl at 0.5 lb AI/A plus Prefar. A lower rate of Prowl at 0.25 lb AI/A plus Prefar also caused a reduction of the onion stand compared to the handweeded check or Dacthal.
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2

Bevilaqua, Natalia da Cunha. "Dinâmica e ação do nicosulfuron em híbridos de milho /." Botucatu, 2019. http://hdl.handle.net/11449/181829.

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Orientador: Caio Antonio Carbonari
Banca: 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 ...
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3

Castro, Edicarlos Batista de [UNESP]. "Dinâmica de glyphosate em plantas de eucalipto." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/131956.

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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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4

Castro, Edicarlos Batista de 1987. "Dinâmica de glyphosate em plantas de eucalipto /." Botucatu, 2015. http://hdl.handle.net/11449/131956.

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Orientador: Caio Antonio Carbonari
Banca: 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 ...
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5

Clifford, Philip A. (Philip Alan). "Validation of a Coupled Herbicide Fate and Target Plant Species Effects Model." Thesis, University of North Texas, 1989. https://digital.library.unt.edu/ark:/67531/metadc332422/.

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A series of experiments provided data to parameterize and validate a coupled herbicide fate and target plant species effects model. This simulation model is currently designed to predict responses of water hyacinth populations to treatments of the dimethylamine formulation of 2,4- dichloro-phenoxy acetic acid (2,4-D -DMA). Experiments investigated 1) the response of water hyacinth to varying exposures of 2,4-D (DMA); 2) the role of water hyacinth density and herbicide interception in treatment effectiveness using 2,4-D (DMA); and 3) the importance of root exposure to obtain control of water hyacinth using 2,4- D (DMA). Results demonstrated the importance of leaf or canopy interception of 2,4-D (DMA) sprays in obtaining control of water hyacinth populations. The critical threshold plant tissue concentration of 2,4-D (DMA) required to elicit maximum mortality (98%) was estimated to be approximately 12 mg 2,4-D per kg water hyacinth tissue (wet weight). Root uptake apparently plays little or no role in the effectiveness of this herbicide for controlling water hyacinth growth. Validation trials illustrated the efficacy of the current model. The model was validated with data from a field operation. This research has provided considerable insight into optimal use of this auxin-type herbicide for control of water hyacinth, a monocotyledon.
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6

Ingratta, William J. "Effects of preplant herbicides on the establishment of Vaccinium Angustifolium Ait." Thesis, McGill University, 1986. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65398.

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7

SATTI, MOHAMED AHMED EISA. "THE MECHANISM OF ACTION OF FLUAZIFOP-BUTYL, HALOXYFOP-METHYL, AND SETHOXYDIM HERBICIDES ON WHEAT (TRITICUM AESTIVUM L.) SEEDLINGS (CHLOROPLAST DEVELOPMENT)." Diss., The University of Arizona, 1985. http://hdl.handle.net/10150/188097.

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Haloxyfop-methyl 2-[4-[ [3-chloro-5-(trifluoromethyl)-2-pyridinyl] oxy] phenoxy] propanoate, fluazifop-butyl (±)-2-[4-[ [5-(trifluoromethyl)-2-pyridinyl] oxy] phenoxy] propanoate, and sethoxydim 2- [1-(ethoxyimino)butyl]-5- [2-(ethylthio)propyl] -3-hydroxy-2-cyclohexen-1-one modified chloroplast pigment, growth, anatomy, and ultrastructure of pre- and postemergent-treated wheat (Triticum aestivum 'Pavon 76') seedlings. Seedlings were grown under 16 h photoperiod (105 μE/M²/S) at 32/24 C day/night temperature. Pigment, growth and anatomical studies were made on pre- and postemergent-treated seedlings. Postemergent treatments were applied to 6-day-old seedlings. Carotenoid levels were reduced by 90 to 94% in preemergent-treated seedlings at 5 x 10⁻⁵ M for each herbicide. Postemergent application of 10⁻³ M haloxyfop-methyl and sethoxydim caused a reduction of 11 and 15% in carotenoid concentration than the control, respectively. Also, they produced a significant reduction in chlorophyll a and total chlorophyll concentration. Preemergent treatment with 5 x 10⁻⁶ M of each herbicide caused a reduction of 78 to 91% in leaf fresh weight and 72 to 84% reduction in root dry weight as compared to the control. Height of the seedlings was reduced by 79 to 86% of the control. Postemergent treatments with 10⁻³ M of each herbicide reduced the length of the second leaf by 98%, whereas length of the first leaf was reduced by 36% following haloxyfop-methyl treatment and 45% following fluazifop-butyl or sethoxydim treatments. Fresh weight of leaf tissue treated with 10⁻³ M of each herbicide was reduced by 40%. Preemergent treatment of the seedlings with 3 x 10⁻⁶ and 5 x 10⁻⁶ M haloxyfop-methyl or with 5 x 10⁻⁶ M fluazifop-butyl or sethoxydim caused 35 to 50% enlargement of mesophyll cells as compared to the control. These cells appeared to contain less cytoplasm. Post- emergent application of 10⁻³ M of each herbicide caused swelling of mesophyll cells. Ultrastructural studies showed that plastids of seedlings germinated in 5 x 10⁻⁶ M of each herbicide were disrupted, swollen, and lacked internal thylakoids but contained masses of plastoglobuli. The chloroplasts of postemergent-treated seedlings had fewer granal and intergranal thylakoids, but the injury to plastids was less severe than in preemergent treatments.
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8

Xavier, Elouize. "Mecanismos de resistência e resposta aos herbicidas inibidores da ALS e da PROTOX em Euphorbia heterophylla L." Universidade Tecnológica Federal do Paraná, 2014. http://repositorio.utfpr.edu.br/jspui/handle/1/858.

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Euphorbia heterophylla (EPHHL) é uma importante planta daninha na agricultura mundial, e a resistência aos herbicidas dificulta ainda mais o seu controle. Assim, conhecer o nível de resistência, os seus mecanismos e a persistência destas populações resistentes nas lavouras é fundamental para o estabelecimento de estratégias de prevenção e manejo. Foram realizados experimentos, objetivando estudar a resistência de EPHHL aos herbicidas inibidores da ALS e PROTOX nos níveis bioquímico, de planta e populacional. O capítulo I objetivou confirmar a ocorrência de resistência aos inibidores da ALS e determinar se existe resistência cruzada aos herbicidas dos grupos químicos das imidazolinona, sulfoniluréia, pirimidil-benzoato e sulfonanilida em biótipos de EPHHL com resistência múltipla (ALS e PROTOX). O capítulo II objetivou confirmar a existência de novos biótipos de EPHHL com resistência a PROTOX nos estados do Paraná e Rondônia e determinar se existe resistência cruzada aos herbicidas dos grupos químicos difeniléteres, ftalamida, triazolinona, oxadiazol e pirimidinedione. O capítulo III objetivou comparar a atividade da enzima ALS de biótipos com resistência múltipla com biótipo suscetível, na ausência e na presença dos herbicidas inibidores enzimáticos imazapyr, imazethapyr e nicosulfuron. O capítulo IV objetivou caracterizar as atividades das enzimas peroxidase, catalase e superóxido dismutase, em biótipos de EPHHL suscetível e com resistência múltipla, pela aplicação de herbicidas inibidores da PROTOX. E o capítulo V objetivou identificar a persistência de populações resistentes aos inibidores da ALS de EPHHL em lavouras da região Sudoeste e Oeste do Paraná que apresentavam resistência em levantamento prévio e verificar a existência de resistência de EPHHL ao glifosato nestas lavouras. Os resultados destes capítulos confirmaram que os biótipos de EPHHL Bom Sucesso do Sul, Vitorino, Vilhena e Medianeira, com suspeita de resistência múltipla aos inibidores da ALS e PROTOX, apresentam a resistência aos herbicidas inibidores da ALS e da PROTOX e esta sendo cruzada aos 4 grupos químicos dos inibidores da ALS e aos 5 grupos químicos dos inibidores da PROTOX, testados. A resistência dos biótipos de EPHHL aos inibidores da ALS é atribuída à menor sensibilidade da enzima a estes herbicidas. A atividade das enzimas antioxidantes superóxido dismutase, peroxidase e catalase, para os biótipos resistentes e suscetível é dependente do herbicida e da dose utilizada e pode ser um dos mecanismos envolvidos na resistência aos inibidores da PROTOX. Os biótipos de EPHHL resistentes aos herbicidas inibidores da ALS permanecem nas áreas mesmo após longo período de constatação da resistência. Plantas de EPHHL com resistência aos inibidores da PROTOX também permanecem nas áreas, no entanto em menor frequência.
Euphorbia heterophylla (EPHHL) is an important weed species in world agriculture and its control becomes difficult due to herbicide resistance. To develop proper EPHHL management strategies it is important to know the level and the mechanisms of resistance and persistence of resistant populations in the fields. Experiments were carried out to study the resistance of EPHHL to ALS and PROTOX inhibitors at biochemical, plant and population levels. The objectives on chapter I are to confirm the occurrence of resistance to ALS inhibitors and to determine whether there is cross resistance to other chemical groups, such as imidazolinone, sulfonylurea, pyrimidinyl (thio) benzoates and triazolopyrimidines in biotypes of EPHHL with multiple resistance (ALS and PROTOX). The objectives on chapter II are to confirm the existence of new EPHHL biotypes with resistance PROTOX in the states of Paraná and Rondônia and to determine whether there is cross resistance to other chemical group, such as diphenyl ethers, N-phenyl-phthalimide, triazolinone, oxadiazole and pyrimidinedione. The objectives on chapter III are to evaluate the activity of the ALS enzyme from biotypes with multiple resistance and to compare it to the enzyme activity of susceptible population in the absence and in the presence of the herbicides imazapyr, imazethapyr and nicosulfuron. The objectives on chapter IV is to characterize the activity of several antioxidant enzymes, such as peroxidase, catalase and superoxide dismutase in EPHHL biotypes treated with PROTOXinhibiting herbicides. The objective on chapter V are to identify the persistence of EPHHL populations resistant to ALS inhibitors on fields from Southwest and Western Paraná that were resistant in a previous survey and check for resistance to glyphosate in EPHHL these crops. The results support the hypothesis that EPHHL biotypes from Bom Sucesso do Sul, Vitorino, Vilhena and Medianeira have multiple resistance to ALS and PROTOX inhibitors. Four EPHHL biotypes are cross-resistant to all ALS chemical groups and five populations are cross-resistant to the PROTOX inhibitors tested. The resistance to ALS inhibitors on the EPHHL biotypes evaluated is attributed to the lower sensitivity of the herbicide target enzyme. The activity of all antioxidant enzymes, both on the resistant and susceptible biotypes, is dependent of the herbicide and on the dose used and can be one of the mechanisms of resistance to PROTOX inhibitors. The biotypes of EPHHL resistant to ALS-inhibiting herbicides remain in the area even after long-term observation of resistance. The resistance to PROTOX inhibitors also remains in areas, but less frequently.
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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.

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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 ...
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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.

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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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11

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.

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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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12

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.

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Orientador: Caio Antonio Carbonari
Banca: 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
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13

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.

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Orientador: Carlos Gilberto Raetano
Banca: 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.
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14

Moraes, Carolina Pucci de 1989. "Controle e hormesis de glyphosate em Brachiaria decumbens /." Botucatu, 2016. http://hdl.handle.net/11449/143503.

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Orientador: Edivaldo Domingues Velini
Banca: 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)
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15

Silva, Ferdinando Marcos Lima 1981. "Hormesis de herbicidas em soja /." Botucatu :, 2014. http://hdl.handle.net/11449/110940.

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Orientador: Edivaldo Domingues Velini
Coorientador: 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 ...
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16

Krolikowski, Valquiria. "Comportamento morfo-fisiológico de Commelina benghalensis em resposta a herbicidas aplicados em pós-emergência /." Ilha Solteira, 2015. http://hdl.handle.net/11449/124429.

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Orientador: Fernando Tadeu de Carvalho
Banca: Edson Lazarini
Banca: Gustavo Pavan Mateus
Resumo: 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
Abstract: 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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17

Santos, Izabela Thais dos. "Método para estudar a dinâmica de herbicidas em palha /." Botucatu, 2019. http://hdl.handle.net/11449/183491.

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Orientador: Edivaldo Domingues Velini
Coorientador: Ivana Paula Ferraz Santos de Brito
Banca: Caio Antonio Carbonari
Banca: Leandro Tropaldi
Resumo: Com a proibição da realização de queimadas para a colheita da cana-de-açúcar, e a implantação da colheita mecanizada, foi originado o sistema de produção denominado cana crua. Nele há o acúmulo de grandes quantidades de resíduos na superfície do solo após a colheita, sendo a cultura implantada sobre essa palhada. Nesse sistema a camada de palha pode interferir na dinâmica dos herbicidas, pois é uma barreira a ser transposta até atingir o solo. Visando obter informações acerca da dinâmica de diferentes produtos, o objetivo desse trabalho foi avaliar a transposição de herbicidas simulando aplicações direto na palha e diluída na água de chuva em palha de cana- de-açúcar. O estudo realizado no NUPAM, visando determinar a dinâmica de transposição dos herbicidas atrazine, diuron, fomesafen, glyphosate, haloxyfop-p- methyl, hexazinone, indaziflam, S-metolachlor e sulfentrazone em palha de cana-de- açúcar. Utilizou-se delineamento inteiramente ao acaso, com quatro repetições, sendo a palha utilizada cortada em 0,5 x 0,5 cm e acondicionada em cápsulas de polietileno. Tendo 9 tratamentos x 3 épocas experimentais x 2 condições. Sendo a primeira condição, a simulação da chegada do herbicida na superfície da palha após a aplicação direta da calda com pipeta de repetição de 40 μL do volume de calda de cada produto por unidade experimental, enquanto na segunda condição, foi simulada a chegada do herbicida na palha após a ocorrência de chuvas, com 40 μL do volume de calda de cada produto apl... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: With the burning fires prohibition for the sugarcane harvesting, and the mechanized harvest implantation, the production system called raw cane was originated. There is accumulation of large amounts of residues on the soil surface after harvest, and the crop is implanted on this straw. In this system the straw layer may interfere with herbicide dynamics, since it is a barrier to be transposed until reaching the ground, and in order to obtain information about the dynamics of different products, the objective of this work was to evaluate the herbicides transposition simulating direct applications in straw and diluted in rainwater in sugarcane straw. The study was carried out at NUPAM, aimed to determine the transposition dynamics of the herbicides atrazine, diuron, fomesafen, glyphosate, haloxyfop-p-methyl, hexazinone, indaziflam, S- metolachlor and sulfentrazone in sugarcane straw. A completely randomized design with four replications was used, the straw being cut into 0.5 x 0.5 cm and packed in polyethylene capsules. Having 9 treatments x 3 times experimental x 2 conditions. Being the first condition, the simulation of herbicide arrival on the straw surface after the direct application of the syrup with a 40 μL repeating pipette of each product volume per experimental unit, while in the second condition, the herbicide arrival was simulated in the straw after the occurrence of rain, with 40 μL of the volume of syrup of each product applied per experimental unit during the 25 mm rainfall simulation. Soon after, 25, 50, 75 and 100 mm accumulated rain blades and 50, 75 and 100 mm were simulated for the first and second experiments, respectively. The herbicides determination in the solutions was performed by means of chromatographic analyzes using the LCMS / MS system. Data were submitted to normality and homogeneity tests and were subsequently submitted to variance analysis by the F test, with the ...
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18

Giovanelli, Bruno Flaibam. "Seletividade de herbicidas sobre milho EnList /." Botucatu, 2019. http://hdl.handle.net/11449/183406.

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Orientador: Caio Antonio Carbonari
Banca: Edivaldo Domingues Velini
Banca: Ricardo Victória Filho
Resumo: A tecnologia EnList foi desenvolvida pela empresa Corteva Agriscience, e permite a aplicação dos herbicidas 2,4-D e haloxyfop-methyl sobre o milho, devido à presença do gene aad-1, além da resistência ao glyphosate e amônio glufosinato. O objetivo deste trabalho foi avaliar a seletividade de diferentes herbicidas sobre a cultura do milho com a tecnologia EnList. Os experimentos foram conduzidos em campo e casa de vegetação. Os herbicidas aplicados foram: haloxyfop-methyl, 2,4-D, e glyphosate. Os ensaios realizados em casa-de-vegetação foram organizados em delineamento inteiramente casualisado, constituídos por cinco repetições. Os herbicidas foram aplicados em pós-emergência (V4), e obteve-se as seguintes variáveis: taxa de transporte de elétrons do Fotossistema II (Electron Transport Rate - ETR), injúria visual, e altura aos 7, 14, 21 e 28 dias após aplicação (DAA). Aos 28 DAA, foram coletadas as plantas para a obtenção da massa seca final. Os experimentos 1 e 2 corresponderam a aplicação de todos os herbicidas acima, tanto de forma isolada como em misturas. Neste mesmo estudo, foi instalado um ensaio adicional a campo para testar os parâmetros produtivos, porém com a adição de amônio-glufosinato. Os demais experimentos constituíram-se de ensaios de dose-resposta para cada um dos três herbicidas estudados, comparando-se um material com a tecnologia EnList, e sua isolinha sem o gene aad-1. Portanto, os ensaios 3 e 4 se referiram a aplicação de doses crescentes de 2,4-D, que f... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The EnListTM traits were developed by Corteva Agriscience, and provide both 2,4-D and haloxyfop-methyl resistance for maize due to the aad-1 gene. In addition, it presents glyphosate and ammonium-glufosinate resistance. The objective of this research was to assess the selectivity of different herbicides for EnListTM maize. The experiments were conducted both in the field and in greenhouse. The herbicides applied were: haloxyfop-methyl, 2,4-D, and glyphosate. The greenhouse treatments were arranged in a completely randomized design and consisted of five replications. The herbicides were applied in post-emergence (V4), and the variables obtained were: Electron transport rate of photosystem II (Electron Transport Rate - ETR), visual injury, and plant height at 7, 14, 21 and 28 days after application (DAA). At 28 DAA, the plants were cut for obtaining the final dry mass. The experiments 1 and 2 corresponded to the application of all the herbicides cited above, both alone and in mixtures. In this same study, an additional field trial was conducted for testing the production parameters, adding ammonium-glufosinate to some treatments. The other experiments consisted of dose-response assays for each of the herbicides cited, comparing a material with the EnListTM technology, and its isoline (non aad-1 material). The experiments 3 and 4 referred to increasing doses of 2,4-D application, which were: 0; 456; 912; 1.824; 3,648 and 7,296 g a.e ha-1. Experiments 5 and 6 corresponded to the following doses of haloxyfop-methyl: 0; 63; 126; 252; 504 and 1.008 g a.i ha-1, and in addition to the variables above, the total lipid content was analyzed by ethereal extract analysis. In experiment 7, six doses of glyphosate (0; 480; 960; 1,920; 3,840; 5,760 g a.a ha-1) were tested for each material. In the first study, the applications did not result on visual injuries or decrease of the other parameters, such as yield ...
Mestre
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19

Maliphant, Paula. "The effect of pesticide stress on diatoms." Thesis, University of Hertfordshire, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309720.

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20

Haas, John Kade Patterson Michael Gene. "Effect of weed management on fruiting position and yieldof Roundup Ready Flex cotton." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/HAAS_JOHN_45.pdf.

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21

Souza, Fabiany Lilyani Gonçalves [UNESP]. "Qualidade de sementes de soja convencional e transgênica em função da dessecação das plantas com glyphosate." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/110942.

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A máxima qualidade das sementes de soja é expressa na maturidade fisiológica, mas, a colheita nesse estádio fenológico não é recomendada, devido ao elevado teor de água nas sementes e o excesso de folhas e hastes verdes nas plantas. Com o intuito de antecipar a colheita, a prática da dessecação química, com o herbicida glyphosate, vem sendo estudada em soja e requer alguns procedimentos, visando a preservação da qualidade fisiológica das sementes no campo. Desse modo, o trabalho teve como objetivo avaliar a qualidade fisiológica de sementes de soja de cultivares convencionais e transgênicas, oriundas de plantas dessecadas com herbicida glyphosate, em diversas épocas de dessecação. A dessecação química com o herbicida glyphosate (2,0 L.ha-1) foi realizada quando os estádios fenológicos R6.0, R7.1, R7.2 e R7.3 das plantas das cultivares BRS 133, Conquista, BRS 243RR e BRS 246RR foram atingidos. As determinações e testes para avaliação da qualidade das sementes foram: teor de água, massa de 100 sementes, germinação, primeira contagem de germinação, envelhecimento acelerado, emergência de plântulas no campo, índice de velocidade de emergência de plântulas no campo, condutividade elétrica, comprimento de plântulas e massa de matéria seca de plântulas. O delineamento experimental adotado foi o de blocos casualizados, dispostos em esquema de parcelas subdivididas, com quatro repetições, totalizando 20 tratamentos. As parcelas constaram de quatro cultivares (BRS 133, Conquista, BRS 243RR e BRS 246RR) e as subparcelas corresponderam a quatro épocas de dessecação, que corresponderam a quatro estádios da cultura (R6.0, R7.1, R7.2 e R7.3) e uma testemunha para cada cultivar (sem dessecação). Os tratamentos foram dispostos em esquema fatorial com 4 cultivares x 4 épocas de dessecação, mais as testemunhas e as médias foram comparadas pelo teste de ...
The maximum quality of soybean seeds is expressed in physiological maturity, but, harvest is not recommended in this phase, due to the high water content in seeds and excess leaves and green stems on the plants. With the aim of anticipating the harvest, the practice of chemical desiccation, with the herbicide glyphosate, has been studied in soybean and requires some procedures, aiming at the preservation of the physiological quality of seeds in the field. In this way, the work aimed to evaluate the physiological quality of soybean seeds of conventional and transgenic cultivars from desiccated plants with herbicide glyphosate, in various periods of desiccation. Chemical desiccation with the herbicide glyphosate (2,0L.ha-1) was performed when the phenological stages R6.0, R7.1, R7.2 and R7.3 plants of cultivars BRS 133, Conquista, BRS 243RR and BRS 246RR were achieved. Tests for evaluation of the quality of the seeds were: water content, mass of 100 seeds, germination, first count of germination, accelerated aging, emergence of seedlings in the field, speed index of seedling emergence in the field, electrical conductivity, seedling length and mass of the dry matter of seedlings. The experimental design was randomized block, arranged in plots scheme subdivided, with four repetitions, totaling 20 treatments. The parcels consisted of four cultivars (BRS 133, Conquista, BRS 243RR and BRS 246RR) and the subplots corresponded to four periods of desiccation, which corresponded to four stages of culture (R6.0, R7.1, R7.2 and R7.3) and a witness to every cultivar (without desiccation). Treatments were arranged in factorial scheme 4 cultivars x 4 times of desiccation, more witnesses and the averages were compared by t test the probability 5. The application of glyphosate in phenological stages R6.0 and R7.1 of soybean plants, conventional cultivars BRS 133 and Conquista, negatively influences the physiological ...
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22

Souza, Fabiany Lilyani Gonçalves 1979. "Qualidade de sementes de soja convencional e transgênica em função da dessecação das plantas com glyphosate /." Botucatu :, 2013. http://hdl.handle.net/11449/110942.

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Orientador: Cláudio Cavariani
Banca: Edvaldo Aparecido Amaral da Silva
Banca: Silvio José Bicudo
Banca: Ricardo Augusto Dias Kanthack
Banca: Mariana Zampar Toledo
Resumo: A máxima qualidade das sementes de soja é expressa na maturidade fisiológica, mas, a colheita nesse estádio fenológico não é recomendada, devido ao elevado teor de água nas sementes e o excesso de folhas e hastes verdes nas plantas. Com o intuito de antecipar a colheita, a prática da dessecação química, com o herbicida glyphosate, vem sendo estudada em soja e requer alguns procedimentos, visando a preservação da qualidade fisiológica das sementes no campo. Desse modo, o trabalho teve como objetivo avaliar a qualidade fisiológica de sementes de soja de cultivares convencionais e transgênicas, oriundas de plantas dessecadas com herbicida glyphosate, em diversas épocas de dessecação. A dessecação química com o herbicida glyphosate (2,0 L.ha-1) foi realizada quando os estádios fenológicos R6.0, R7.1, R7.2 e R7.3 das plantas das cultivares BRS 133, Conquista, BRS 243RR e BRS 246RR foram atingidos. As determinações e testes para avaliação da qualidade das sementes foram: teor de água, massa de 100 sementes, germinação, primeira contagem de germinação, envelhecimento acelerado, emergência de plântulas no campo, índice de velocidade de emergência de plântulas no campo, condutividade elétrica, comprimento de plântulas e massa de matéria seca de plântulas. O delineamento experimental adotado foi o de blocos casualizados, dispostos em esquema de parcelas subdivididas, com quatro repetições, totalizando 20 tratamentos. As parcelas constaram de quatro cultivares (BRS 133, Conquista, BRS 243RR e BRS 246RR) e as subparcelas corresponderam a quatro épocas de dessecação, que corresponderam a quatro estádios da cultura (R6.0, R7.1, R7.2 e R7.3) e uma testemunha para cada cultivar (sem dessecação). Os tratamentos foram dispostos em esquema fatorial com 4 cultivares x 4 épocas de dessecação, mais as testemunhas e as médias foram comparadas pelo teste de ...
Abstract: The maximum quality of soybean seeds is expressed in physiological maturity, but, harvest is not recommended in this phase, due to the high water content in seeds and excess leaves and green stems on the plants. With the aim of anticipating the harvest, the practice of chemical desiccation, with the herbicide glyphosate, has been studied in soybean and requires some procedures, aiming at the preservation of the physiological quality of seeds in the field. In this way, the work aimed to evaluate the physiological quality of soybean seeds of conventional and transgenic cultivars from desiccated plants with herbicide glyphosate, in various periods of desiccation. Chemical desiccation with the herbicide glyphosate (2,0L.ha-1) was performed when the phenological stages R6.0, R7.1, R7.2 and R7.3 plants of cultivars BRS 133, Conquista, BRS 243RR and BRS 246RR were achieved. Tests for evaluation of the quality of the seeds were: water content, mass of 100 seeds, germination, first count of germination, accelerated aging, emergence of seedlings in the field, speed index of seedling emergence in the field, electrical conductivity, seedling length and mass of the dry matter of seedlings. The experimental design was randomized block, arranged in plots scheme subdivided, with four repetitions, totaling 20 treatments. The parcels consisted of four cultivars (BRS 133, Conquista, BRS 243RR and BRS 246RR) and the subplots corresponded to four periods of desiccation, which corresponded to four stages of culture (R6.0, R7.1, R7.2 and R7.3) and a witness to every cultivar (without desiccation). Treatments were arranged in factorial scheme 4 cultivars x 4 times of desiccation, more witnesses and the averages were compared by t test the probability 5. The application of glyphosate in phenological stages R6.0 and R7.1 of soybean plants, conventional cultivars BRS 133 and Conquista, negatively influences the physiological ...
Doutor
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23

Westwell, Jane Marie. "Effect of spore immobilisation of the pathogenicity of a Cochliobolus isolate." Thesis, University of Westminster, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240167.

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24

Macedo, Gabrielle de Castro. "Crescimento, desenvolvimento e produtividade de arroz submetido a baixas doses de glyphosate /." Botucatu, 2018. http://hdl.handle.net/11449/154314.

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Orientador: Caio Antonio Carbonari
Banca: Edivaldo Domingues Velini
Banca: Marcelo de Almeida Silva
Banca: Natália Corniani
Banca: Marcelo Rocha Corrêa
Resumo: O emprego de substâncias tóxicas as plantas, como o glyphosate, em doses muito menores que as recomendadas comercialmente pode ocasionar alterações em varáveis como crescimento, acúmulo de biomassa, altura, conteúdo de proteína e resistência a doenças. Desta forma, os objetivos deste trabalho foram realizar estudos para uma melhor compreensão das alterações bioquímicas, fisiológicas e fenológicas do arroz causadas por subdoses de glyphosate. O experimento 1 foi realizado à campo, na Fazenda Experimental Lageado, pertencente à Faculdade de Ciências Agronômicas, FCA/UNESP, Botucatu/SP, nos anos agrícolas de 2015/2016 e 2016/2017. O delineamento experimental utilizado foi o de blocos casualizados, arranjado em esquema fatorial 2x7, sendo o primeiro fator época de aplicação do glyphosate (V3 ou R1) e, o segundo, as doses do herbicida (0; 7,5; 15; 30; 60; 120 e 240 g e.a. ha-1), com quatro repetições. Foram avaliados a produtividade, o comprimento de panículas, número de perfilhos por m², peso de 1000 grãos, número de grãos por panícula, a fertilidade de espiguetas e o número de dias entre a aplicação e o início de cada fase fenológica. Os experimentos 2 e 3 foram realizados em casa de vegetação, no Núcleo de Pesquisas Avançadas em Matologia (NUPAM), pertecentente à Faculdade de Ciências Agronômicas, FCA/UNESP, Botucatu/SP. O experimento 2 seguiu delineamento inteiramente casualizado em esquema fatorial (7x3) com cinco repetições. Os tratamentos foram constituídos por sete doses d... (Resumo completo, clicar acesso eletrônico abaixo)
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Doutor
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25

Tickes, Barry. "The Effect of Irrigation Practices on the Performance of Lettuce Herbicides." College of Agriculture, University of Arizona (Tucson, AZ), 1999. http://hdl.handle.net/10150/219955.

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The herbicides used in lettuce have changed little in more than 30 years. Poast was registered for grass control in the 1980's although preemergent applications of Kerb, Balan and Prefar have been the principal herbicides used in lettuce production since the mid 1960's. Balan was changed from a 1.5 lb./gal. Emulsifiable concentrate to a 60% dry flowable formulation in the mid 80's, Kerb has always been a 50% wettable powder and Prefar is still a 4 lb./gal. emulsifiable concentrate. Growers are constantly changing cultural practices to improve production or to become more efficient. The change in one cultural practice can, and often does, effect other cultural practices. The use of sprinklers to establish lettuce has become increasingly widespread in the Yuma area over the past 20 years. Kerb and Prefar can be mechanically incorporated into shaped beds although both are commonly incorporated with irrigation water. The change in irrigation practices during stand establishment from furrow irrigation to sprinklers has effected the performance of both Kerb and Prefar. Balan is normally disced into the soil prior to bed formation and is not as effected by irrigation practices during stand establishment. Four tests are presented in this paper that help explain the effect of irrigation practices on the performance of Kerb and Prefar.
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26

Zama, Paul. "Studies on the mechanisms of action of the herbicide safener CGA- 92194." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/49970.

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CGAr92194 {α-[1,3-dioxolan-2-yl-methoxy)imino]benzeneacetonitrile} is a herbicide safener that is used as a seed dressing agent (1.25 g ai/kg seeds) to protect grain sorghum [Sorghum bicolor (L.) Moench] against metolachlor [2-chloroi-N-(2-ethyl-6-methylphenyl-N-(2-methoxy1-methylethyl)acetamide] injury. The potential adverse phytotoxic effects and the mechanisms of the protective action of this safener were studied in laboratory experiments. Adverse phytotoxicity was assessed by comparing CGA-92194 and the herbicide safeners cyometrinil {(Z)-α[(cyanomethoxy)imino]benzeneacetonitrile} and flurazole [phenylmethyl 2-chloro-4-(trifluromethyl)-5-thiazolecarboxylate] for their effects on CO₂ fixation, protein, DNA, RNA and lipid syntheses of enzymatically isolated leaf cells of soybean [Clycine max (L.) Merr]. At physiological concentrations of less than 10 μM, CGA-92194, cyometrinil and flurazole were stimulatory of all metabolic processes. At 100 μM, the safeners were inhibitory of the five processes with flurazole being the most potent. The mechanisms of the safening action of CGA-92194 were studied by examining the potential interactions of this safener with metolachlor at the levels of uptake and macromolecular syntheses in enzymatically isolated leaf mesophyll protoplasts of grain sorghum. The influence of CGA-92194 on the in vitro reactivity of metolachlor with glutathione (GSH) and it metabolism by sorghum seedlings were also examined. When CGA-92194 and metolachlor were given simultaneously, CGA-92194 enhanced the uptake of ¹⁴C-metolachlor into the sorghum protoplasts in a concentration-dependent pattern. Thus, interference with herbicide uptake is not involved in the protective action of this safener Treatments with metolachlor and CGA-92194 in combination inhibited the incorporation of ¹⁴C-uracil, ³H-thymidine and ¹⁴C-acetate into sorghum protoplast macromolecules less than metolachlor given alone, suggesting the potential involvement of a competitive antagonism in the mechanism of action of CGA-92194. The metabolic activity and growth of sorghum seedlings grown from CGA-92194-pretreated seeds was significantly lower than that of seedlings grown from untreated seeds at 10 or 20 days after planting, The relationship of these effects of CGA-92194 to its safening action is unclear at the present time. CGA-92194 increased the in vitro chemica1 reactivity of metolachlor for GSH in a concentration-dependent pattern, Sorghum seedlings grown from safener-pretreated seeds enhanced ¹⁴C-metolachlor absorption and stimulated its metabolism via conjugation to GSH. This stimulation was reduced by tridiphane [2-(3,5-dichlorophenyl)-2-(2,2,2-trichloroethy1)- oxirane] a potent inhibitor of plant GSH-S-transference enzymes, These results indicate that a safener-induced stimulation of the spontaneous or enzymatic conjugation of metolachlor with GSH is most likely involved in the protective action of CGA-92194. It is suggested that the safening mechanism of action of CGA—92194 involves a sequence of multilevel interactions which together contribute to the overall protection of grain sorghum from metolachlor injury.
Ph. D.
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27

Hanlon, A. R. M. "The effect of simazine on chlorophyll a fluorescence in axenic diatom monocultures and in estuarine microphytobenthic biofilms." Thesis, University of Essex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390991.

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28

Nietschke, Brett Steven. "Integrated strategies for wild oat (Avena spp.) management in southern Australian farming systems." Title page, contents and abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09PH/09phn677.pdf.

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Bibliography: leaves 128-146. Study was undertaken to determine the occurence and species incidence of wild oats in a major cropping region of southern Australia. Population dynamic studies were undertaken at two sites to define the seed bank decline and emergence pattern of several wild oat populations over a three year period. Management studies were conducted to determine appropriate strategies for the control of wild oats in southern Australian farming systems.
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Latorre, Débora de Oliveira [UNESP]. "Intoxicação e alterações metabólicas do algodão sensível e resistente ao amônio glufosinate." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/110932.

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As cultivares de algodão Liberty Link ® são aquelas que resistem à aplicação do amônio glufosinate a uma dose que normalmente seria recomendada para os demais biótipos da espécie. Estas cultivares de algodão são constituídas geneticamente com um gene que codifica a produção da enzima fosfinotric ina acetil transferase (PAT), responsável pela acetilação do amônio glufosinate, inativando - o na planta. A cultivar de algodão FiberMax ® 975 WideStrike por também apresentar em seu DNA o gene PAT apresentaria o comportamento de seu metabolismo intermediário às cultivares convencional e Liberty Link ® . O objetivo do trabalho foi avaliar as alterações metabólicas e a intoxicação das plantas de algodão Wide Strike ® comparadas a plantas Liberty Link ® e convencionais, quando submetidos ao herbicida amônio glufosinate. Os es tudos foram conduzidos em casa de vegetação n a Faculdade de Ciências Agronômicas - FCA / UNESP - Campus de Botucatu (SP). Dois experimentos foram instalad os simultaneamente utilizand o cultivares as cultivares transgênicas e convencional , sendo o primeiro para avaliar a intoxicação e alterações na fotossíntese e o segundo para quantificar compostos relacionados a rota de ação do herbicida amônio glufosinate . Foram semeadas 5 sementes p or vaso de três cultivares de algodão FM 993 (convencional), FM 975WS ® (transgênica) e IMACD 6001LL ® (transgênica) e, aos 15 dias após a emergência (DAE) foi realizado o desbaste das plantas, mantendo duas plantas por vaso. Quando as plantas apresentaram 2 folhas verdadeiras (25 dias após emergência) realizou - se a primeira aplicação dos ...
The Liberty Link cotton cultivars are those that resist a dose of ammonium glufosinate application that normally would be recommended for other biotypes species .These cotton plants are constitute genetically with gene that encodes the production of enzyme phosphinothricin acetyl transferase (PAT) responsible for the acetylation of glufosinate ammonium, inactivating it in the plant. The cotton cultivar FiberMax® 975 WideStrike has present in i ts DNA the gene PAT and present intermediate metabolism to conve ntional cultivars and Liberty Link ®. The purpose of the study was to evaluate the metabolic changes and the intoxication of WideStrike®cotton plants compared with Liberty Link ® and conventional plants, when treated to ammonium glufosinate herbicide. The studies were carried out in a greenhouse at the Faculty of Agricultural Sciences, “Júlio de MesquitaFilho State University – Botucatu Campus (SP). Were conducted two experiments simultaneously using the transgenic and conventional cultivars, the first one to evaluate the toxicity and changes in photosynthesis and the secondto quantify compounds related to the herbicide ammonium glufosinate action route. Five seeds were sown of each cultivar per pot of the three cotton cultivars FM 993 (non - genetically modi fied), FM 975WS® (genetically modified) and IMACD 6001LL® (genetically modified) and at 15 days after emergence (DAE) was performed thinning of the plants, keeping two plants per pot. When the plants had two true leaves (25 days after emergence) held the ...
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30

Latorre, Débora de Oliveira 1986. "Intoxicação e alterações metabólicas do algodão sensível e resistente ao amônio glufosinate /." Botucatu :, 2014. http://hdl.handle.net/11449/110932.

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Orientador: Caio Antonio Carbonari
Coorientador: Anderson Luis Cavenaghi
Banca: Elza Alves Correa
Resumo: As cultivares de algodão Liberty Link ® são aquelas que resistem à aplicação do amônio glufosinate a uma dose que normalmente seria recomendada para os demais biótipos da espécie. Estas cultivares de algodão são constituídas geneticamente com um gene que codifica a produção da enzima fosfinotric ina acetil transferase (PAT), responsável pela acetilação do amônio glufosinate, inativando - o na planta. A cultivar de algodão FiberMax ® 975 WideStrike por também apresentar em seu DNA o gene PAT apresentaria o comportamento de seu metabolismo intermediário às cultivares convencional e Liberty Link ® . O objetivo do trabalho foi avaliar as alterações metabólicas e a intoxicação das plantas de algodão Wide Strike ® comparadas a plantas Liberty Link ® e convencionais, quando submetidos ao herbicida amônio glufosinate. Os es tudos foram conduzidos em casa de vegetação n a Faculdade de Ciências Agronômicas - FCA / UNESP - Campus de Botucatu (SP). Dois experimentos foram instalad os simultaneamente utilizand o cultivares as cultivares transgênicas e convencional , sendo o primeiro para avaliar a intoxicação e alterações na fotossíntese e o segundo para quantificar compostos relacionados a rota de ação do herbicida amônio glufosinate . Foram semeadas 5 sementes p or vaso de três cultivares de algodão FM 993 (convencional), FM 975WS ® (transgênica) e IMACD 6001LL ® (transgênica) e, aos 15 dias após a emergência (DAE) foi realizado o desbaste das plantas, mantendo duas plantas por vaso. Quando as plantas apresentaram 2 folhas verdadeiras (25 dias após emergência) realizou - se a primeira aplicação dos ...
Abstract: The Liberty Link cotton cultivars are those that resist a dose of ammonium glufosinate application that normally would be recommended for other biotypes species .These cotton plants are constitute genetically with gene that encodes the production of enzyme phosphinothricin acetyl transferase (PAT) responsible for the acetylation of glufosinate ammonium, inactivating it in the plant. The cotton cultivar FiberMax® 975 WideStrike has present in i ts DNA the gene PAT and present intermediate metabolism to conve ntional cultivars and Liberty Link ®. The purpose of the study was to evaluate the metabolic changes and the intoxication of WideStrike®cotton plants compared with Liberty Link ® and conventional plants, when treated to ammonium glufosinate herbicide. The studies were carried out in a greenhouse at the Faculty of Agricultural Sciences, "Júlio de MesquitaFilho" State University - Botucatu Campus (SP). Were conducted two experiments simultaneously using the transgenic and conventional cultivars, the first one to evaluate the toxicity and changes in photosynthesis and the secondto quantify compounds related to the herbicide ammonium glufosinate action route. Five seeds were sown of each cultivar per pot of the three cotton cultivars FM 993 (non - genetically modi fied), FM 975WS® (genetically modified) and IMACD 6001LL® (genetically modified) and at 15 days after emergence (DAE) was performed thinning of the plants, keeping two plants per pot. When the plants had two true leaves (25 days after emergence) held the ...
Mestre
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31

Cooley, William Edward. "Comparative studies on the modes of action of SC-0224 and glyphosate." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54493.

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The biological actions of the herbicides SC-0224 (trimethylsulfonium carboxymethylaminomethylphosphonate) and glyphosate [N-(phosphonomethyl)glycine] (PMG) were compared. In each study trimethylsulfonium iodide (TMS-I) was included as a treatment because the trimethylsulfonium ion is a constituent of the SC-0224 molecular structure. In inflated duckweed (Lemna gibba L.), both formulated and technical grade forms of SC-0224 were found to be much more phytotoxic to duckweed than either formulated or technical grade forms of glyphosate. The growth inhibition caused by glyphosate was partially prevented by different combinations of the aromatic amino acids phenylalanine, tyrosine, and tryptophan; whereas, the duckweed growth inhibition caused by SC-0224 could not be reduced by the same amino acid combinations. TMS-I and SC-0224 were found to be equally phytotoxic to duckweed. SC-0224 caused larger increases than glyphosate in the pool levels of amino acids; the increases caused by SC-0224 were similar, however, to those caused by trimethylsulfonium iodide. Expressed on a per gram fresh weight basis none of the chemical treatments caused significant changes in soluble protein or the incorporation of ¹⁴C-leucine into soluble protein. On a per flask basis (allowing for decreased growth in treated flasks), both herbicides and TMS-I caused significant decreases in soluble protein and ¹⁴C-leucine incorporation. SC-0224 and TMS-I caused larger decreases than glyphosate in both cases but the SC-0224 and TMS-I treatments were not significantly different. These data indicate that differences in the phytotoxicity of SC-0224 .and glyphosate may be due to the action of the trimethylsulfonium ion of the SC-0224 structure. The effects of these herbicides on the conversion of shikimate to anthranilate in a cell-free extract of Klebsiella pneumoniae ATCC 25306 were also compared. SC-0224 and glyphosate equally inhibited the production of anthranilate indicating that SC-0224 has action similar to glyphosate on the shikimate pathway. The effects of these herbicides on photosynthetic electron transport (the Hill reaction) was determined using isolated thylakoids from Alaska pea (Pisum sativum L.). The action of SC-0224 was compared with the action of glyphosate, TMS-I and diuron [3-(3,4-dichorophenyl)-1,1-dimethylurea]. SC-0224, glyphosate and TMS-I did not inhibit the Hill reaction at concentrations up to 10 mM; whereas, diuron caused an almost total inhibition at 0.10 mM. The results of this study indicate that SC-0224 is not an inhibitor of photosynthetic electron transport. These studies indicate that both constituents of the SC-0224 structure, TMS and PMG, are phytotoxic and may act independently.
Ph. D.
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32

Rademacher, William Hale. "Effects of prometryn applied in irrigation water on furrow irrigated cotton and residue persistence." Thesis, The University of Arizona, 1985. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1985_193_sip1_w.pdf&type=application/pdf.

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33

Mansooji, Ali Mohammad. "Herbicide resistance in wild oats, Avena spp." Title page, contents and abstract only, 1993. http://web4.library.adelaide.edu.au/theses/09PH/09phm289.pdf.

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34

Maneechote, Chanya. "Mechanisms of herbicide resistance in wild oats (Avena spp.)." Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phm274.pdf.

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Bibliography : leaves 159-184. This study found at least three mechanisms of resistance to the acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides. A modified target -site was responsible for moderate and high resistance to herbicides at the whole plant level. Enhanced herbicide metabolism and reduced translocation of herbicide to the target site was observed in one resistant biotype each.
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35

Nelson, J. M., D. A. Dierig, and G. L. Hart. "Effect of Planting Date, Nitrogen Fertility and Postemergence Herbicides on Lesquerella Production." College of Agriculture, University of Arizona (Tucson, AZ), 1994. http://hdl.handle.net/10150/201436.

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Lesquerella is a potential crop plant that produces seeds containing hydroxy fatty acids similar to those in castor beans. An important step in the commercialization of this plant for Arizona farms is the development of an efficient agronomic production system. Research on cultural practices for lesquerella was conducted during the 1991-92 and 1992-93 seasons. Results of planting date experiments indicate that early fall planting dates are superior to late fall or winter dates in terms of dry matter production and seed yield. Lesquerella produced a marked response to nitrogen (N) in tests comparing different N rates. In a postemergence weed control test, several herbicides gave good control of small winter weeds.
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36

Dias, Roque de Carvalho 1990. "Seletividade de herbicidas aplicados em pós-emergência em espécies de grama /." Botucatu, 2018. http://hdl.handle.net/11449/153643.

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Orientador: Edivaldo Domingues Velini
Coorientador: Ivana Paula Ferraz Santos de Brito
Banca: Caio Antonio Carbonari
Banca: Leandro Tropaldi
Resumo: As plantas daninhas interferem nos gramados, prejudicando a sua formação, estabelecimento, qualidade e estética. Destaca-se dentre as diversas técnicas o uso de herbicidas, entretanto, são escassas as informações referentes a seletividade desses produtos em gramados. Desse modo, o objetivo desse trabalho foi avaliar a seletividade de herbicidas aplicados em pós-emergência sobre as espécies Axonopus compressus (grama São Carlos), Paspalum notatum (grama Batatais), Zoysia japonica (grama Esmeralda) Cynodon dactylon x Cynodon transvaalensis (grama Bermuda - Tifton 419). Foram realizados dois experimentos, todos em casa de vegetação e repetidos em diferentes momentos. As quatro espécies de grama foram transplantadas em vasos com capacidade de 2 L e aos 40 dias após o transplantio foram realizadas as aplicações dos tratamentos. Os tratamentos constituíram-se pela aplicação de 13 herbicidas (g i.a. ha-1): chlorimuron-ethyl (15); halosulfuron (112,5); imazapyr (125,0); metsulfuron-methyl (2,4); dicamba (288); triclopyr (600); 2,4-D (2010); clomazone nas formulações convencional e microencapsulada (1200); atrazine (1250); bentazon (600); flumioxazin (30); sulfentrazone (600), além de tratamento controle (sem aplicação de herbicida) para cada espécie estudada. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições. As avaliações da taxa de cobertura verde (TCV) das espécies de gramas foram realizadas aos 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 41, 48, 55 ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Weeds interfere with turfgrass, hampering their formation, establishment, quality and aesthetics. Among the several techniques, the use of herbicides stands out, however, the information regarding the selectivity of these products in turfgrass is scarce. Thus, the aim of this work was to evaluate the selectivity of herbicides applied in post-emergence on the species Axonopus compressus (broadleaf carpetgrass), Paspalum notatum (bahiagrass), Zoysia japonica (japanese lawn grass), Cynodon dactylon x Cynodon transvaalensis (bermudagrass -Tifton 419). Two studies were conducted, all in a greenhouse and repeated at different times. The four turfgrass species were transplanted in vessels with a capacity of 2 L and at 40 days after transplanting the applications of the treatments. The treatments consisted of the application of 13 herbicides (g i.a. ha-1): chlorimuron-ethyl (15); halosulfuron (112.5); imazapyr (125.0); metsulfuron-methyl (2.4); dicamba (288); triclopyr (600); 2,4-D (2010); clomazone in conventional and microencapsulated formulations (1200); atrazine (1250); bentazon (600); flumioxazin (30); sulfentrazone (600), in addition to control treatment (without herbicide application) for each species studied. The experimental design was completely randomized with four replicates. The green cover rate (TCV) evaluations of the turfgrass species were performed at 0, 3, 6, 9, 12, 15, 18, 21, 24, 27, 41, 48, 55 and 62 days after application (DAA); and height and phytointoxication, in the same TCV period, except for 0 DAA. The levels of total chlorophyll and carotenoids were evaluated at 9, 18 and 27 DAA and dry biomass of the shavings at 27 and 62 DAA. The obtained data were submitted to analysis of variance by the F test, being the total chlorophyll content and dry biomass of the chips, compared to the Tukey test (p≤0.05). On the other hand, the results of TCV, phytotoxification and herbicide ...
Mestre
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37

Marchesi, Bruna Barboza. "Efeitos de formulações e intervalos sem chuva na absorção, translocação e eficácia de Glyphosate e 2,4-D /." Botucatu, 2016. http://hdl.handle.net/11449/136291.

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Orientador: Edivaldo Domingues Velini
Banca: Ulisses Rocha Antuniassi
Banca: Pedro Luis da Costa Aguiar Alves
Resumo: Com o objetivo de avaliar os efeitos de formulações e de intervalos sem chuva três experimentos foram conduzidos afim de se obter informações sobre a deposição, absorção, translocação e eficácia dos herbicidas 2,4-D e glyphosate, isolados e em mistura, em plantas de Conyza canadensis. Todos os estudos foram realizados em casa-de-vegetação em delineamento inteiramente casualizado e em esquema fatorial, com 6 herbicidas (780 g e.a. ha-1 do herbicida EnlistTM; 780 + 820 g e.a. ha-1 da mistura formulada EnlistDuoTM; 780 g e.a. ha-1 de DMA 806 BR; 820 g e.a. ha-1 de Glizmax®Prime; 780 + 820 g e.a. ha-1 da mistura dos herbicidas DMA 806 BR + Glizmax®Prime e 780 + 820 g e.a. ha-1 da mistura de EnlistTM + Glizmax®Prime). Para o estudo de absorção o fatorial foi 6X4, com os 6 herbicidas e 4 intervalos de lavagem, com 5 repetições; para os de deposição e translocação o fatorial foi 6X2, sendo os 6 herbicidas e 2 regiões (ápice e base), com 6 repetições; e para o de eficácia, 6X5, os 6 herbicidas e 5 intervalos de chuva, com 4 repetições. No estudo de absorção foram quantificados os teores dos herbicidas internos e externos às plantas. Nos de deposição e translocação a quantificação dos herbicidas internos às plantas foi realizada para ambos, sendo que no de translocação a quantificação foi realizada aos 2 e 4 dias após a aplicação (DAA). No de eficácia foi realizada a avaliação visual de fitointoxicação aos 7, 14, 21 e 28 DAA e a massa seca aos 28 DAA. A mistura de 2,4-D e glyphosate, sendo ela formulada ou em tanque, aumentou a absorção e a eficácia do 2,4-D no controle de Conyza canadensis. A absorção de 2,4-D foi contínua ao longo das primeiras 24 horas com aumento dos teores internos e da porcentagem de controle com o avanço dos intervalos sem chuva ou lavagem. As folhas da base de Conyza canadensis receberam as maiores deposições de 2,4-D ...
Abstract: With the objective to evaluate the effects of formulations and rainless intervals three experimentes were done in order to obtain information about deposition, absorption, translocation and efficacy of the herbicides 2,4-D and glyphosate, alone or in mixture, in Conyza canadensis plants. All studies were performed in green house in a completely randomized design and in a factorial with 6 herbicides (780 g a.i. ha-1 of the herbicide EnlistTM; 780 + 820 g a.i. ha-1 of the formulated mixture EnlistDuoTM; 780 g a.i. ha-1 of DMA 806 BR; 820 g a.i. ha-1 of Glizmax®Prime; 780 + 820 g a.i. ha-1 of the herbicides mixtures DMA 806 BR + Glizmax®Prime and 780 + 820 g a.i. ha-1 of the mixture EnlistTM + Glizmax®Prime). To the absorption study the fatorial was 6X4, with 6 herbicides and 4 washing intervals, with 5 repititions; to the deposition and translocation study, the factorial was 6x2, with 6 herbicides and 2 regions (apex and base), with 6 repetitions; and to the efficacy study, 6X5, with the 6 herbicides and 5 rain intervals, with 4 repetitions. In the absorption study were quantified the levels of internal and external herbicides to plants. In the deposition and translocation, quantifying the internal herbicides to plants was conducted for both and to translocation the quantification performed at 2 and 4 days after application (DAA). For the efficacy study it was conducted a visual evaluation of injury at 7, 14, 21 and 28 DAA and dry mass at 28 DAA. The mixture of 2,4-D and glyphosate, formulated or in a tank mix, increased the absorption and the efficacy of 2,4-D in control of Conyza canadensis. The 2,4-D absorption was uniform throughout the first 24 hours with increasing internal levels and the percentage of control with the advance of intervals without rain or washing. The base leaves of Conyza canadensis received the biggest deposition of 2,4-D and glyphosate, mainly responsible for the ...
Mestre
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38

Anderson, Annette. "The effects of acetolactate synthase (ALS) inhibiting herbicides on the growth, yield, nodulation and nitrogen fixation of selected legumes." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09pha545.pdf.

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Bibliography: leaves 251-268. The main aim of this thesis is to determine the effects of sulfonylurea residues and in-crop usage of selected ALS-inhibiting herbicides on the growth, yield, nodulation and nitrogen fixation of legumes under alkaline conditions. Reviews literature concerning ALS-inhibiting herbicides, nitrogen fixation and the effects of herbicides on legumes, rhizobia, nodulation and nitrogen fixation; Glasshouse trial investigating the effects of flumetsulam on biomass and nodulation of chickpea; Field trail investigating the effects of sulfonylurea residues and 'in crop' usage of flumetsulam on medic shoot biomass and seed yield and the effects of chlorsulfuron residues and 'in crop' usage of flumetsulam and imazethapyr on chickpea shoot biomass, grain yield and nitrogen fixation; develops methodologies for experiments investigating the effects of ALS-inhibiting herbicides on nodulation of chickpea.
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39

Matos, Ana Karollyna Alves de 1991. "Uniformidade na deposição e dinâmica de formulações de diuron e sulfentrazone em solo, palha e plantas de cana-de-açúcar /." Botucatu, 2018. http://hdl.handle.net/11449/154466.

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Orientador: Caio Antonio Carbonari
Banca: Edivaldo Domingues Velini
Banca: Marcus Barifouse Matallo
Banca: Leandro Tropaldi
Banca: Natalia Corniani
Resumo: A mistura de herbicidas é uma prática recorrente em diversos países do mundo, e proporciona vários benefícios para o manejo de plantas daninhas. Contudo, em virtude das possíveis interações entre os herbicidas que compõem uma mistura, é necessário o conhecimento dos efeitos da mistura de herbicidas, a fim de determinar os seus possíveis efeitos nas plantas e na dinâmica dos produtos. Diante disso, o objetivo desse trabalho foi avaliar os efeitos da aplicação em mistura comercial e mistura em tanque dos herbicidas diuron e sulfentrazone, na dinâmica dos herbicidas em solos e na palha; deposição em campo, e o comportamento em variedades de cana-de-açúcar. Em todos os experimentos foi realizada a aplicação da mistura comercial (Stone®) e mistura em tanque (Herburon 500 BR® + Boral 500 SC®) dos herbicidas diuron e sulfentrazone, nas doses de 1750 g i.a. ha-1 e 875 g i.a. ha-1, respectivamente. No primeiro estudo, avaliou-se os efeitos das formulações na lixiviação dos herbicidas diuron e sulfentrazone em solos com diferentes texturas. Em cada experimento, foi utilizado um solo (textura argilosa, arenosa e média) para preencher as colunas, que após a aplicação das formulações foram submetidas a simulação de diferentes lâminas de chuva (40, 80 e 120 mm). As soluções lixiviadas foram coletadas para posterior detecção e quantificação dos herbicidas, por cromatografia líquida e espectrometria de massas (LC-MS/MS). Para o estudo de dinâmica em palha foram utilizadas cápsulas de laminad... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract:The mixture of herbicides is a recurrent practice in different countries of the world, and provides several benefits for the weed management. However, because of possible interactions between herbicides that compose a mixture, knowledge of the effects of the herbicides mixture is necessary to determine its possible effects on plants and products dynamics. Therefore, the objective of this work was to evaluate the effects of the application in commercial mixture and tank mixture of the herbicides diuron and sulfentrazone, the dynamics of herbicides in soils and straw; deposition on the field, and behavior in sugarcane varieties. In all experiments, the commercial mixture (Stone®) and tank mixture (Herburon 500 BR® + Boral 500 SC®) of the herbicides diuron and sulfentrazone were applied at doses of 1750 g a.i. ha-1 and 875 g a.i. ha-1, respectively. In the first study, were evaluated the effects of the formulations on the leaching of the diuron and sulfentrazone herbicides in soils with different textures. In each experiment, a soil (clayey, sandy and medium texture) was used to fill the columns that after the application of the formulations were submitted to simulation of different rainfalls (40, 80 and 120 mm). The leached solutions were collected for further detection and quantification of the herbicides, by liquid chromatography and mass spectrometry (LC-MS/MS). For the study of dynamics in straw were used polypropylene laminated capsules filled with sugarcane straw (equivalent to 10 tons ha-1). In the capsules submitted to the application of the herbicides was carried out in the periods 1, 15 and 30 days after application (DAA) the simulation of different rainfalls (5, 10, 20, 50 and 100 mm) and collected leachate water for further chromatographic quantification. The spray solutions used were stored for further determination of the surface tension. The deposition experiment was carried out in the ...
Doutor
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40

Yenne, Samuel P. "Investigations on the mechanism of action of the oxime ether safeners for the protection of grain sorghum against metolachlor." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54821.

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Herbicide safeners (protectants, antidotes) are used to protect crop plants from herbicide injury. Currently our understanding of the mechanisms involved in the protection of plants by safeners is not well defined; therefore, investigations were conducted to elucidate the mechanism(s) of action of the oxime ether safeners. Molecular comparisons of selected herbicide-safener combinations using computer-aided molecular modeling revealed that the chemical structures of safeners and herbicides are very similar at the molecular level; and, indicate that these compounds could bind at the same active site of the target protein or they may serve as inducers of metabolic enzymes which detoxify herbicides. Metolachlor at 10 μM and seed-applied CGA-133205 had no effect on germination while treatment with seed-applied oxabetrinil significantly reduced germination of grain sorghum. Results from experiments on ¹⁴C-acetate incorporation into lipids indicate that metolachlor and the oxime ether safeners influence lipid metabolism causing a redistribution of carbon in the lipid fractions of germinating sorghum roots. Results from studies with acetyl-CoA carboxylase indicate that this enzyme is not a target site for either metolachlor or the oxime ether safeners. Metolachlor and the oxime ether safeners enhanced glutathione levels in grain sorghum seedlings at 12 to 48 hr after imbibition was initiated with oxabetrinil being more stimulatory than metolachlor or CGA-133205. Glutathione reductase activity was also stimulated in safener-treated grain sorghum seedlings. Both safeners slightly enhanced nonenzymatic and enzymatic conjugation of metolachlor with reduced glutathione. Oxabetrinil conjugated enzymatically or nonenzymatically with reduced glutathione at a slow rate, but CGA-133205 did not. These data suggest that during the early stages of seed germination and seedling development of grain sorghum, safeners can enhance the detoxication of metolachlor by enhancing glutathione levels and enzymatic and nonenzymatic conjugation of metolachlor with glutathione. It appears that oxabetrinil and CGA-133205 are conferring protection to grain sorghum by increasing the rate of metolachlor metabolism.
Ph. D.
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41

Fajri, Abolhassan. "Nitrogen fixation by pasture legumes : effects of herbicides and defoliation." Title page, table of contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phf1755.pdf.

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Bibliography: leaves 209-254. Experiments detailed in this thesis, evaluate the impact of various herbicides and herbicide mixtures on the growth, nodulation and nitrogen fixation of annual pasture legumes, the efficacy of the herbicides for weed control, and the potential role of mechanical defoliation to replace herbicides, leading to lower cost and more sustainable farming systems.
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42

Somireddy, Upender Reddy. "Effect of Herbicide-Organic Mulch Combinations on Weed Control and Herbicide Persistence." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1325255792.

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43

Diagonel, Guilherme. "Efeito de herbicidas a base de glifosato sobre as respostas fotossintéticas de macrófitas de ecossistemas lóticos tropicais /." Assis, 2019. http://hdl.handle.net/11449/182312.

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Orientador: Ciro Cesar Zanini Branco
Banca: Rosana Marta Kolb
Banca: Régis de Campos Oliveira
Resumo: Vários estudos observacionais sobre macrófitas de ecossistemas lóticos têm contribuído com o aumento do conhecimento ecológico destes organismos nestes ambientes. Entretanto, ainda persistem lacunas importantes neste conhecimento, entre as quais estão as relações de causa e efeito que potencialmente existem entre perturbações provocadas pela atividade antrópica e aspectos da fisiologia e da ecologia destes organismos. Com o objetivo de superar, obviamente em parte, esta lacuna, o presente estudo propõe, através de experimentos laboratoriais, avaliar os efeitos de resíduos de herbicidas usados nas lavouras agrícolas, em especial aqueles a base de glifosato (Roundup®) e seu metabólito (AMPA), sobre parâmetros fotossintéticos de espécies de angiospermas aquáticas típicas de ecossistemas lóticos tropicais. As avaliações das taxas fotossintéticas e de respiração no escuro foram realizadas através da evolução do oxigênio dissolvido, aplicando-se a técnica das garrafas claras e escuras e da fluorescência de clorofila a, que foi avaliada com o fluorômetro subaquático Diving-PAM. Os valores dos parâmetros fotossintéticos medidos/calculados para cada tratamento avaliado foram submetidos à estatística descritiva e as eventuais diferenças entre eles foram avaliadas através da análise de variância utilizando o teste de Scott-Knott e o t-Student. Foram observados alguns poucos efeitos fitotóxicos associados às espécies de macrófitas estudadas, porém, quase nenhuma diferença... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Even with many observational studies regarding lotic ecosystems, macrophytes that have contributed with great knowledge about the ecology of these organisms in these environments. However, there are still important gaps in this knowledge, among which are the cause and effect relationships that potentially exist between disturbances caused by anthropic activity and aspects of the physiology and ecology of these organisms. With the objective of overcoming, in part, this gap, the present study proposes, through laboratory experiments, to evaluate the effects of herbicide residues used in agricultural crops, especially those based on glyphosate (Roundup®) and your metabolite (AMPA) on photosynthetic parameters of aquatic angiosperm species typical of tropical lotic ecosystems. The evaluation of photosynthetic rates and respiration in the dark were performed through the evolution of dissolved oxygen, applying the light and dark bottle technique and chlorophyll a fluorescence, which was evaluated with the Diving-PAM underwater fluorometer. The values of the photosynthetic parameters measured / calculated for each evaluated treatment were submitted to descriptive statistics and any differences between them were evaluated through analysis of variance using the Scott-Knott and t-Student test. In spite of this global pattern, species responded specificially to exposure to Roundup® and AMPA, and Egeria densa was the one that registered the greatest susceptibility to the loss of... (Complete abstract click electronic access below)
Mestre
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44

Vallotton, Nathalie. "Effect assessment of fluctuating exposure of herbicides with different modes of action on algae /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17461.

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45

Rumpa, Mafia Mahabub. "EFFECT OF PPO-INHIBITING HERBICIDES ON MALE-TO-FEMALE SEX RATIO OF AMARANTHUS PALMERI." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2259.

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TITLE: EFFECT OF PPO-INHIBITING HERBICIDES ON MALE-TO-FEMALE SEX RATIO OF AMARANTHUS PALMERI Background: Amaranthus palmeri S. Wats. (Palmer amaranth) is a dicotyledonous, dioecious species having separate male and female plants that forces outcrossing, ensures genetic diversity, and is recognized as one of the most noxious, invasive agricultural weed pests in the Mid-West. It can be characterized by extended emergence periodicity, aggressive growth habit, high fecundity, and high water use efficiency as well as high competitive ability. Fisher (1930) predicted 1: 1 primary sex ratios after the period of parental investment, but initial field studies indicated that A. palmeri populations were female-biased, departing from the expected 1:1 sex ratio. Therefore, managing population sex ratios would be an important consideration for controlling A. palmeri populations, as this species has become resistant to several herbicide modes of action. Objective: This study was conducted to investigate the male-to-female sex ratio of Amaranthus palmeri following exposure to PPO-inhibiting herbicides, to gain a better understanding of potential effects of herbicide application on the population sex ratio. Methods: A greenhouse experiment and a two-year field experiment were conducted at the Horticultural Research Center, Southern Illinois University Carbondale in spring 2016 and Collinsville, Illinois in the summer season of 2015 and 2016, respectively. The greenhouse experiment was conducted by applying two protoporphyrinogen oxidase (PPO)-inhibiting herbicide treatments of either lactofen (Cobra) or fomesafen (Flexstar) on four different Illinois populations (Cahokia, Collinsville, Rend Lake, and Massac). The field experiment was conducted for two years in a soybean field throughout the growing season of 2015 and 2016 in Collinsville, Illinois, USA. This study included 12 pre- and post-emergence PPO-inhibiting herbicide treatments of 10 herbicides with 3 replicates to investigate the variation among sex ratios by treatment. Results: For the greenhouse experiment, depending on the population, herbicide treatments expressed a male-to-female sex ratio of either 1:1 or male-biased in contrast to the female-biased field observations. This study also suggested that these PPO-inhibiting herbicide treatments may have an influence on the growth and sex ratio of A. palmeri populations. The field experiment indicated that A. palmeri populations have a female-biased sex ratio in untreated controls. The pre-emergence application of sulfentrazone (Spartan) at rates of 226.8 to 340.19 g a.i./ha provided the highest control efficacy, as compared to other treatments. Post-emergence-only applications provided limited control over the population. Fomesafen (Flexstar) was the only PPO-inhibiting herbicide which led to a male-based population in both years. In the future, and with increased understanding of the mechanism behind sex expression in A. palmeri, knowledge of plant-environment relationships such as these could provide an opportunity to reduce seed production in populations by favoring the production of males.
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46

Dadazio, Tais Santo 1989. "Obtenção e análise de espectros de absorção de luz por herbicidas /." Botucatu, 2018. http://hdl.handle.net/11449/180635.

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Orientador: Edivaldo Domingues Velini
Coorientador: Leandro Tropaldi
Banca: Caio Antonio Carbonari
Banca: Fernando Tadeu de Carvalho
Banca: Luiz Lonardoni Foloni
Banca: Ferdinando Lima Silva
Resumo: Cada substância apresenta um padrão de resposta específico quando submetidas à radiação solar. No entanto, estudos que comparam diferentes moléculas, a fim de identificarem padrões de comportamento são escassos. Portanto, estudos que relacionam o padrão de absorbância com a radiação solar disponível, buscando estimar o potencial de fotodegradação de defensivos, são inexistentes na literatura. Nesse contexto, esse trabalho estudou a absorção de luz por diferentes herbicidas e metabólitos com o objetivo de prever a sensibilidade desses compostos à fotólise em condições de campo e a necessidade de utilizar manejos ou tecnologias que possam reduzir a degradação por efeito da luz. Foram investigadas 36 substâncias, correspondendo a herbicidas e seus metabólitos. Cada solução foi analisada por meio de varredura das absorbâncias das substâncias na faixa de 185 a 900nm (Ultravioleta (UV)/ Visível (VIS)/Infra vermelho(IF)). Posteriormente, o potencial de cada comprimento de onda em promover a fotólise de um composto específico foi determinado multiplicando-se a disponibilidade de luz no espectro solar padrão e a absorbância observada na solução padronizada desse composto no mesmo comprimento de onda. De acordo com os resultados, cada substância apresentou faixas de comprimento de ondas com maior potencial de absorção, especialmente na região do VIS e com outros estudos permitirão avaliar quais compostos podem ser utilizados para protegê-las. Assim, foi possível agrupar as substancias ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Each substance has a specific response pattern when subjected to solar radiation. However, studier comparing differente molecules in order do identify behavior patterns are scarce. Therefore, studies that relate the absorbance pattern to the available solar radiation, seeking to estimate the photodegradation potential of pesticides are not available in the literature. In this context, this work studied the absorption of light by different herbicides and metabolites in order to predict the sensitivity of these compounds to photolysis underf field conditions and the need to use care or technologies that can reduce light degradation. There were investigated 36 substances, corresponding to herbicides and thei metabolites. Each solution was analyzed by scanning the absorbances of substances in the range of 185 to 900 nm (UV/VIS/IF). Subsequently, the potential of each wavelength promoting the photolysis of a specific compound was determined by multiplying the light availability in the standard solar spectrum and the observed absorbance in the standard solution of that compound at the same wavelenght. According to the results, each substance showed wavelenght ranges with greater absorption potential, and with other studier, it will be possible to evaluate which compounds can be used to protect them. Thus, it was possible to group the substances in relation to the photodegradation index in descending order in the UVA, UVB and UVC radiation range. The herbicides pendimenthalin and trifluralin stand out by expressively absorbing visible light (400 to 700 nm)
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47

Upham, Brad Luther. "Interactions of paraquat and nitrodiphenylether herbicides with the chloroplast photosynthetic electron transport in the activation of toxic oxygen species." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/82614.

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Abstract:
The interactions of paraquat (methylviologen) and diphenylether herbicides with the Mehler reaction as investigated. Sera from two different rabbits (RS1 & RS2) were examined for their patterns of inhibition of the photosynthetic electron transport (PET) system. Serum from RS2 was greatly hemolyzed. Fifty ul of RS1 serum were required for 100% inhibition of a H₂O → methylviologen(MV)/O₂ reaction, whereas only 10 µl of a 1:10 dilution of RS2 were needed for 100% inhibition. The γ-globulin fraction from purified rabbit serum (RS1) did not inhibit PET, indicating that the antibody fraction of the rabbit serum does not contain the inhibitor. It appears that the inhibitor is from the hemolyzed red blood cells. Rabbit sera, added to chloroplast preparations prior illumination, caused no inhibition of a H₂O → MV/O₂ reaction while addition of rabbit sera during illumination inhibited the H₂O → MV/O₂ reaction within 1-3 s. Various Hill reactions were used to determine the site of inhibition. Rabbit sera inhibited photosystem I (PSI) Hill reactions, but did not inhibit a photosystem II (PSI II) Hill reaction indicating that inhibition is on the reducing side of PSI. It would be expected that a H₂O → Ferredoxin (Fd)/NADP Hill reaction should also be blocked. Surprisingly, rabbit sera did not inhibit this reaction. These results were interpreted as supportive evidence for parallel (branched) electron transport on the reducing side of PSI. Six pyridyl derivatives {benzylviologen, 2-anilinopyridine, 1,2-bis(4-pyridyl)ethane, 1,2-bis(4-pyridyl)ethylene, 2-benzoylpyridine, and 2-benzylaminopyridine} and five heme-iron derivatives {hemoglobin, hemin, hematin, ferritin, and ferrocene} were screened for their potential to counteract paraquat toxicity on pea (Pisum sativum L. cv. Little Marvel) isolated chloroplasts. H₂O → MV/O₂ and H₂O → Fd/NADP+ were the two Hill reactions assayed with these compounds. Antagonists of paraquat toxicity should inhibit the first Hill reaction but not the latter. None of the pyridyl derivatives examined inhibited the reaction H₂O → MV/O₂. Ferritin and ferrocene were also ineffective as inhibitors of this reaction. Hemoglobin inhibited the reaction H₂O → MV/O₂ without inhibiting the reaction H₂O → Fd/NADP+, providing protection to pea chloroplasts against paraquat. Hemin and hematin inhibited both Hill reactions examined. Hemin and hematin also inhibited H₂O → diaminodurene (ox) and durohydroquinone → MV/O₂ Hill reactions but not the dichlorophenylindolphenol(red) → MV/O₂ and diaminodurene(red) → MV/O₂ Hill reactions. These results indicate that hemin and hematin are inhibiting photosynthetic electron transport in the plastoquinone pool region. Potential involvement of hydroxyl and alkoxyl radicals in the peroxidative action of the p-nitro diphenyl ether herbicides acifluorfen was evaluated under laboratory conditions. Methional was added to illuminated pea thylakoids and its oxidation to ethylene was used as an indicator of hydroxyl and alkoxyl radical synthesis. Oxyfluorfenstimulation of the rate of methional oxidation was dependent on light, photosynthetic electron transport and hydrogen peroxide since it was not observed under dark conditions or in the presence of DCMU and catalase. Addition of FeEDTA, a catalyst of the Fenton reaction, stimulated the oxyfluorfen-induced enhancement of methional oxidation six-fold suggesting that hydroxyl radicals are synthesized through a Fenton reaction. Acifluorfen, nitrofen and nitrofluorfen inhibited the rate of methional oxidation whereas, acifluorfen-methyl had no effect on the rate of methional oxidation even at high concentrations (1 mM). Nitrofluorfen at 1 mM was the only p-nitro diphenyl ether herbicide tested which inhibited photosynthetic electron transport of pea thylakoids. In experiments with pea leaf discs, acifluorfen at low concentrations stimulated the rate of methional oxidation, while acifluorfen-methyl, nitrofen and nitrofluorfen had no effect. These data indicate that hydroxyl and alkoxyl radicals could be involved in the mechanism of cellular damage caused by oxyfluorfen, but they are not important for the activity of the diphenyl ether herbicides acifluorfen, acifluorfen-methyl, nitrofen, and nitrofluorfen. Diethyldithiocarbamate (DEDTC) does not accept electrons from the photosynthetic electron transport (PET), but can donate electrons to a photosystem I (PSI) Mehler reaction in the presence of the following PET inhibitors: diuron, dibromothymoquinone, and bathophenanthroline. It cannot photoreduce PSI in the presence of cyanide, a PET inhibitor. These data indicate that the site of electron donation is after the plastoquinone pool. Ascorbate is not required for the ability of DEDTC to donate electrons to PSI. There is no photoreductant activity by DEDTC in a ferredoxin/NADP Hill reaction. Superoxide dismutase inhibits DEDTC/diuron or bathophenanthroline → MV/O₂ Mehler reaction. Catalase does not restore the consumed O₂ from a DEDTC/diuron → MV/O₂ Mehler reaction, indicating O₂- has not been dissmutating into H₂O₂. These results indicate that superoxide is required for DEDTC ability to donate electrons, therefore DEDTC is limited only to Mehler-type reactions.
Ph. D.
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48

Jean-Jean, Patricia. "Contribution à l'étude des herbicides des plantes médicinales." Lyon 1, 1985. http://www.theses.fr/1985LYO1W034.

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49

Nascimento, Alessandro. "Eficácia de herbicidas aplicados em pré-plantio incorporado na cultura da cana-de-açúcar /." Ilha Solteira, 2016. http://hdl.handle.net/11449/134297.

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Abstract:
Orientador: Fernando Tadeu de Carvalho
Banca: Marcelo Carvalho Minhoto Teixeira Filho
Banca: Marco Antonio de Souza Silva
Resumo: Para o controle eficaz de plantas daninhas na cultura da cana-de-açúcar é pouco provável que uma única aplicação de herbicida em pré-plantio incorporado seja suficiente para manter a cultura no limpo até o seu fechamento. O objetivo do trabalho foi averiguar a eficácia (ou ineficácia) de herbicidas aplicados uma única vez em pré-plantio-incorporado para o controle de plantas daninhas em cana-de-açúcar. O delineamento experimental utilizado foi o de blocos ao acaso, com oito tratamentos e quatro repetições com parcelas de 30 m2 . A eficiência dos herbicidas no controle das plantas daninhas foi avaliada aos 30, 60, 90, 120 e 150 dias após a aplicação (DAA), por meio de uma escala visual, onde 0% = nenhum controle e 100% = controle total das plantas daninhas, considerando-se como eficiente o controle igual ou superior a 80%. Concluiu-se que todos os tratamentos (s-metolachlor a 1,5 e 3,0 L p.c./ha; smetolachlor+atrazin a 1,5 e 3,0 + 3,0 L p.c./ha; trifluralin a 2,0 L p.c./ha e trifluralin+atrazin a 2,0 + 3,0 L p.c./ha) foram altamente seletivos para a cultura da cana-de-açúcar, variedade RB 86-5453 e foram ineficazes para as dicotiledôneas Calopogonium muconoides (aos 150 DAA) e Amaranthus deflexus (aos 120 DAA) e, os tratamentos s-metolachlor+atrazin (1,5 e 3,0 + 3,0 L p.c./ha) e trifluralin+atrazin (2,0 + 3,0 L p.c./ha) foram eficientes para a espécie Panicum maximum. Todos os tratamentos proporcionaram menor crescimento e produtividade da canade-açúcar em relação à testemunha no limpo. Entre as testemunhas observou-se reduções no crescimento e principalmente na produtividade (55%) da testemunha sem capina em relação à capinada. Uma única aplicação dos herbicidas trifluralin, s-metolachlor, atrazin e suas combinações em pré-plantio incorporado, não foram suficientes para manter a cultura de canade-açúcar livre de mato-competição até o seu fechamento, indicando...
Abstract: To the weeds control in the sugarcane is unlikely that a single application of herbicide in preplanting-incorporated is sufficient to maintain the culture in clean until its closing. The objective of the work was to determine the effectiveness (or ineffectiveness) of herbicides applied only once in pre-plant-incorporated for weed control in sugar cane. The experimental design was a randomized block with eight treatments and four replications with plots of 30 m2 . The herbicides efficiency in weed control was assessed at 30, 60, 90, 120 and 150 days after application, through a visual scale, where 0% = no control and 100% = full control of plants weeds, considering how efficient control than or equal to 80%.It was concluded that all treatments (1.5 and 3.0 Lc.p./ha of s-metolachlor; 1.5 and 3.0 L + 3.0 Lc.p./ha of smetolachlor+atrazin; 2.0 Lc.p./ha of trifluralin and 2.0+3.0 Lc.p./ha of trifluralin+atrazin) were highly selective for the culture of sugar cane, variety RB 86-5453 and were ineffective for the dicotyledons Calopogonium muconoides (at 150 DAA) and Amaranthus deflexus (at 120 DAA) and, the treatments s-metolachlor + atrazin (1.5 and 3.0 + 3.0 Lc.p./ha) and trifluralin + atrazin (2.0 L + 3.0 c.p./ha) were effective for the species Panicum maximum. All treatments showed lower growth and yield compared to the control in the clean. Among the controls was observed reductions in growth and 55% reduction in the productivity of the treatment without controlling weeds in relation to treatment weeded. A single application of trifluralin herbicides, smetolachlor, atrazine and their combinations in corporate pre-planting, were not enough to keep the culture of sugarcane free of weed competition until its closure, indicating a need for other methods subsequent control
Mestre
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50

Moreira, Caio Alexandre Ferreira 1987. "Espectro de gotas e deriva de diferentes formulações dos herbicidas 2,4-D e Glyphosate aplicadas com pontas de jato plano com e sem indução de ar /." Botucatu, 2016. http://hdl.handle.net/11449/183163.

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Abstract:
Orientador: Ulisses Rocha Antuniassi
Banca: Otavio Jorge Grigoli Abi-Saab
Banca: Caio Antonio Carbonari
Banca: Paulo Roberto Arbex Silva
Banca: Rone Batista de Oliveira
Resumo: A correta aplicação de produtos fitossanitários resulta em minimização de perdas, e mitigação de danos ambientais. A busca por uma operação de aplicação otimizada tornou a mistura em tanque de produtos fitossanitários uma prática comumente utilizada em todo o mundo. Entretanto, a mistura em tanque pode resultar em alterações físicas na calda, interferindo no espectro de gotas e no risco de deriva. Técnicas para redução de deriva devem ser utilizadas neste processo, especialmente na aplicação de herbicidas. Nesse contexto, este trabalho teve como objetivo avaliar o espectro de gotas e o potencial de deriva gerado por caldas contendo os herbicida 2,4-D e glyphosate em diferentes condições de misturas, aplicadas com duas pontas diferentes. Em uma formulação composta de herbicida 2,4-D sal colina incluindo uma tecnologia para redução da deriva. Esta formulação foi comparada a uma formulação convencional de 2,4-D sal dimetilamina (DMA) de maneira isolada e em pré mistura com glyphosate (sal potássico e sal dimetilamina) e uma mistura pronta (2,4-D sal colina + glyphosate sal dimetilamina). Para isto foram comparados vinte tratamentos, sendo cada tratamento representado por uma calda, constituídas das misturas ou não entre os herbicidas. As avaliações dos tratamentos foram realizadas em dois experimentos. O primeiro pulverizado com uma ponta de jato plano de uso estendido (Teejet XR 11002) e outro com uma ponta jato plano de indução de ar (Teejet AIXR 11002). A pressão de trabalho ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The correct application of pesticides results in loss minimization, and mitigation of environmental damage. The search for an optimal implementation of operation has the mixture in a practical defensive tank commonly used throughout the world. However, the tank-mix can result in physical changes in the spray solution, interferes with droplet spectrum and the risk of drift. Drift reduction techniques to be used in this process, including the application of herbicides. In this context, this study aims to evaluate the spectrum of drops and the potential drift generated by spraying solutions containing the herbicide 2,4-D and glyphosate in different conditions of mixtures applied with two different nozzles. A formulation containing 2,4-D salt choline including a technology for reduction of drift was used. This formulation was compared to a conventional formulation of 2,4-D dimethylamine salt (DMA) in isolation and premix with glyphosate (potassium salt and dimethylamine salt) and a ready mixed (2,4-D + glyphosate salt choline salt dimethylamine). Twenty treatments were compared, each treatment being represented by a spray solution consisting of mixtures of herbicides or not. The treatments were evaluated in two experiments. A sprayed with a jet nozzle extended use plan (Teejet XR 11002) and one with a nozzle jet air induction plan (Teejet AIXR 11002) both at 280 kPa. The Volumetric Median Diameter (VMD) and the percentage of droplets smaller than 105 µm (V105) were obtained from ... (Complete abstract click electronic access below)
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