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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Adjuvant Effects On Herbicide Absorption And Translocation

Dodds, Darrin Matthew 15 December 2007 (has links)
Bispyribac-sodium is an acetolactate synthase (ALS) inhibiting herbicide introduced for control of grasses, broadleaves, and sedges in rice and turf. However, Mississippi and Arkansas rice producers have reported inconsistent barnyardgrass (Echinochloa crus-galli Beauv.) control with bispyribac-sodium. Experiments were conducted to determine if inconsistent barnyardgrass control with bispyribac-sodium could be alleviated through adjuvant technology. Absorption of 14C-bispyribac-sodium was greatest with a proprietary blend of methylated seed oil/organosilicone (MSO/OSL) (0.37 L ha-1) plus urea ammonium nitrate (UAN) (2% v/v) and the proprietary blend of MSO/OSL/UAN (2% v/v) at 80 and 74% of applied 14C-bispyribac-sodium, respectively. The addition of 32% UAN to MSO/OSL and non-ionic organosilicone (OSL/NIS) adjuvant systems resulted in a four- to fiveold increase in absorption compared to treatments without UAN. Maximum absorption was achieved 12 h after application and therefore, bispyribac-sodium should be rainfast at this time. MSO/OSL adjuvants supplied from multiple manufacturers were also examined to determine which provided the highest levels of 14C-bispyribac-sodium absorption as well as herbicidal efficacy and rainfastness. The addition of Rivet® plus UAN or Sil-MES 100® plus UAN to 14C-bispyribac-sodium resulted in the highest levels of absorption among adjuvants supplied. Bispyribac-sodium applied with no adjuvant or with 32% UAN only resulted in significant reductions in control compared to MSO/OSL adjuvant formulations. Addition of MSO or MSO/OSL adjuvants and UAN to bispyribac-sodium resulted in greater than 85% freshweight reduction of barnyardgrass. Bispyribac-sodium applied with MSO or Dyne-A-Pak® was rainfast by two and four hours after application, respectively. Addition of Sil-MES 100® plus UAN or Inergy® plus UAN to bispyribac-sodium reduced the rainfastness interval to 30 minutes and one hour after herbicide application, respectively. Further experiments were conducted to determine if individual components of 32% UAN as well as ammonium sulfate (AMS) would provide control similar to that of 32% UAN. The addition of ammonium chloride, calcium nitrate, and ammonium sulfate at selected rates provided barnyardgrass control similar to that of 32% UAN.
2

EFEITO DO RAINFASTNESS E ADJUVANTE NA APLICAÇÃO DE FUNGICIDAS FOLIARES EM CULTIVARES DE SOJA / EFFECT OF RAINFASTNESS AND ADJUVANTS IN THE FUNGICIDES APPLICATION ON SOYBEANS CULTIVARS

Debortoli, Monica Paula 27 February 2008 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Deposition, distribution and tenacity on the leaf surface can influence the efficacy of the fungicide. The effect of rainfall after the spray might run out fungicides of contact from leaf surface. It can also remove the systemic fungicides, if the spray occurs right after the fungicide application. The goals of this work were (i) performance of fungicides due to the drop spectrum under simulated conditions of rainfall on soybean rust control and (ii) determine the interference of rainfall on the biological efficacy of fungicides in different of soybean cultivars to control Phakopsora pachyrhizi. Two experiments were run out in greenhouse conditions. Experiment 1 studied three spray nozzles (twin flat spray - TJ60 11002; extended range flat spray - XR 11002 and wide angle flat spray - TT 11002), spray a fungicide with and without adjuvant, and four intervals of rain after spraying (0, 30, 60 and 120 minutes); two control treatments (without chemical spray and without rain). Experiment 2 rated the performance of four fungicides (Azoxystrobin + Cyproconazol; Pyraclostrobin + Epoxyconazol, Pycoxistrobin + Cyproconazol and Tebuconazol 250 EC) sprayed on seven cultivars (Coodetec 214 RR, Coodetec 219 RR, Monsoy 8000 RR, Monsoy 8080 RR, Fundacep 56 RR, FMT Tabarana and Nidera 7636 RR). Treatments were exposed to simulated rain at intervals of 0, 30, 60, 120 and 240 minutes after spray. The fungicides were sprayed with CO2 pressurized sprayer. The simulated rain produced a precipitation intensity of 20 mm/4min. The simulated rain caused negative effect on the performance of spraying nozzles and the effectiveness of Phakopsora pachyrhizi and powdery mildew control. Fungicide application with no addition of adjuvant affected the efficacy of soybean rust control due to the occurrence of rain immediately after the spraying. The drops produced by the nozzles XR showed the best drop deposition to the control of the soybean rust. In the absence of adjuvant it was observed less negative effect caused by the rain. When the adjuvant was added to the fungicide, it provided less control than the nozzle TT at 0 and 30 minutes after spraying. It was observed relationship between influences of the rainfastness on the efficiency of disease control provided by fungicides in different levels for the seven cultivars tested. The cultivars Msoy 8000 and Nidera 7636 were more showed higher product washing soon after spraying showing AUCPD superior to the other cultivars when sprayed azoxystrobin + cyproconazol. However the cultivars CD 214, CD 219 and FMT Tabarana suffered minor effect due to the rainfastness. It showed significant differences from the other cultivars as much to the final severity of rust as the AUCPD for the same fungicide. Occurrence of rain immediately after the spraying of pyraclostrobin + epoxyconazol was observed superiority in the disease control of the cultivars Cep 56, Nidera 7636 and CD 219 with smaller values of severity and final AUCPD. The efficiency of control of the fungicide pycoxistrobin + cyproconazol was less affected in cultivars Cep 56 and Nidera 7636 by rainfastness. The fungicide tebuconazol was little affected by rainfastness when sprayed in cultivars Cep 56 and CD 219, but in the CD 214 and Nidera 7636 was negative effect of rain. Yield per plant and weight of a thousand grains showed similar trend considering the final severity and AUCPD of the soybean rust. / A deposição, distribuição e tenacidade na superfície foliar influenciam a eficiência de um fungicida. A ação da chuva, logo após a pulverização, pode remover principalmente fungicidas de contato e também os sistêmicos das superfícies foliares das culturas. O presente trabalho teve por objetivos (i) avaliar o desempenho de pontas de pulverização no controle de doenças da soja em condições de chuva simulada e (ii) determinar impacto da chuva na eficiência biológica de fungicidas em variedades de soja para controle da ferrugem asiática. Foram instalados dois experimentos em casa de vegetação no município de Itaara/RS, no experimento 1 foram testadas três pontas de pulverização (jato plano duplo TJ60 11002; jato leque plano de uso ampliado XR 11002 e leque plano defletor TT 11002), um fungicida com e sem adjuvante e quatro intervalos de chuva após a aplicação (0, 30, 60 e 120 minutos); mais dois tratamentos testemunhas, uma sem controle químico e outra sem chuva. No experimento 2 foi avaliado o comportamento de quatro fungicidas (Azoxistrobina + Ciproconazol + Nimbus; Piraclostrobina + Epoxiconazol, Picoxistrobina + Ciproconazol + Nimbus e Tebuconazole 250 CE) aplicados em sete cultivares (Coodetec 214 RR, Coodetec 219 RR, Monsoy 8000 RR, Monsoy 8080 RR, Fundacep 56 RR, FMT Tabarana e Nidera 7636 RR) quando submetidos à chuva simulada aos 0, 30, 60, 120 e 240 minutos após a aplicação. A aplicação dos tratamentos fungicidas foi realizada com auxílio de pulverizador costal pressurizado à CO2. A chuva simulada foi obtida através de equipamento mecânico munido de aspersor Vejeet 80100, produzindo precipitação de intensidade de 20 mm. Os resultados obtidos mostraram que a chuva causou efeito negativo no desempenho das pontas de pulverização e na eficiência de controle de ferrugem asiática e oídio no experimento 1. Quando não foi utilizado adjuvante em combinação com o fungicida a eficiência de controle foi prejudicada pela ocorrência de chuva logo após a aplicação. A ponta XR apresentou o melhor desempenho no controle da ferrugem da soja quando sem adição de adjuvante, apresentando menor efeito negativo da chuva. Quando foi adicionado adjuvante à calda essa ponta proporcionou controle inferior a TT aos 0 e 30 minutos após a aplicação. No experimento 2 foi verificado que a rainfastness influenciou a eficiência de controle proporcionado pelos fungicidas, em diferentes magnitudes para as sete cultivares testadas. As cultivares Msoy 8000 e Nidera 7636 foram mais suscetíveis a lavagem do fungicida logo após a aplicação apresentando AACPF superior às demais cultivares quando aplicado Azoxistrobina + Ciproconazol, já as cultivares CD 214, CD 219 e FMT Tabarana foram as que sofreram menor impacto da rainfastness com diferenças significativas das outras cultivares tanto na severidade final da ferrugem como na AACPF para o mesmo fungicida. Com ocorrência de chuva logo após a aplicação de piraclostrobina + epoxiconazol foi observada superioridade no controle da doença nas cultivares Cep 56, Nidera 7636 e CD 219 que apresentaram menores valores de severidade final e AACPF. A eficiência de controle do fungicida picoxistrobina + ciproconazol foi menos afetada nas cultivares Cep 56 e Nidera 7636 pela rainfastness. O fungicida tebuconazol foi pouco afetado pela rainfastness quando aplicado nas cultivares Cep 56 e CD 219, já na CD 214 e Nidera 7636 ocorreu impacto negativo da chuva. Para peso de grãos por planta e peso de mil grãos foi observada a mesma tendência de resposta verificada para severidade final e AACP da ferrugem da soja.
3

Evaluation of the rainfastness of selected insecticides in cotton

Barrett, Sara Inez 30 April 2021 (has links)
Rainfastness of insecticides is an understudied aspect of agricultural research. Little is known about the residual of commonly used products for key pests of cotton, as well as their residual after a rainfall event. This project was designed to evaluate the impact of rainfall on the performance of commonly used insecticides for tobacco thrips, Frankliniella fusca (Hinds); tarnished plant bug, Lygus lineolaris (Palisot de Beauvois); and bollworm, Helicoverpa zea (Boddie), management in cotton. Laboratory and field experiments suggest that rainfall occurring within 16 hours after application had a negative impact on the performance of most insecticides. Chemical analyses of leaf tissue using a mass spectrometer confirmed what was observed with field and laboratory experiments. Although direct comparisons between insecticides cannot be made, results from this study suggest that spinosyns and insect growth regulators appeared to have the longest residual after a rainfall event.
4

INFLUÊNCIA DE ADJUVANTES NAS PROPRIEDADES FÍSICO-QUÍMICAS DA CALDA DE INSETICIDAS, NA FORMAÇÃO DE DEPÓSITOS, PENETRAÇÃO CUTICULAR E REMOÇÃO PELA CHUVA / ADJUVANTS INFLUENCE ON PHYSICAL AND CHEMICAL PROPERTIES OF INSECTICIDES SPRAY IN DEPOSIT FORMATION, CUTICULAR PENETRATION AND RAIN-INDUCED REMOVAL

Melo, Adriano Arrué 27 March 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The addition of adjuvants can improve the quality of agricultural chemical sprays and have been an usual practice on the last years. The work presents two papers aiming to study the influence of adjuvant apply on the agricultural spray. The first article, entitled "Influence of adjuvants on the physicochemical characteristics of insecticides spray solution and electron microscope images of the deposits on wheat and corn leaves" evaluate changes in physical and chemical characteristics of the spray solution with the insecticides Thiamethoxam, Imidacloprid and Lambda-cyhalothrin. Were measured the surface tension, droplet contact angle on wheat and maize leaf, droplet coverage and images were made with a scanning electron microscope to better understand the deposit of these insecticides. Adjuvants alter the spray solution physical characteristics improving its wettability, furthermore, the addition of adjuvants may interfere with the deposit characteristics of the tested insecticides. The second article entitled "Tank-mix-adjuvants might improve deposit formation and cuticular penetration, and reduce rain-induced removal of chlorantraniliprole", aimed to verify the interaction of clorantraniliprole insecticide with commercial adjuvants. In this assay, have been studied aspects as adjuvant effect on the deposits formation, cuticular penetration through apple cuticles, droplet coverage and rain effect on the removal of the insecticide in wheat and maize crops. The results showed that the adjuvants play a crucial role in the hydrophobic cover sheet by changing the characteristics of the spray solution, thereby improving the wettability. Furthermore, adjuvants may enhance the absorption of clorantraniliprole insecticide. / A adição de adjuvantes pode melhorar a qualidade das pulverizações agrícolas e tem sido uma prática usual nos últimos anos. O presente trabalho apresenta dois artigos que tem como objetivo, estudar a influencia da utilização de adjuvantes nas pulverizações. O primeiro artigo, intitulado Influência de adjuvantes nas características físico-químicas de caldas de pulverização de inseticidas e imagens de microscópio eletrônico dos depósitos em folhas de trigo e milho avaliou as mudanças nas características físicas e químicas da calda de pulverização com os inseticidas tiametoxam, Imidacloprido e lambda-cialotrina. Sendo mensurada a tensão superficial, o ângulo de contato da gota, em folhas de trigo e milho, a cobertura de gotas e realizadas imagens com microscópio eletrônico de varredura. Os adjuvantes alteram as características físicas da calda, melhorando a sua molhabilidade, além disso, a adição de adjuvantes pode interferir nas características de formação do depósito dos inseticidas testados. O segundo artigo intitulado Tank-mix-adjuvants might improve deposit formation and cuticular penetration, and reduce rain-induced removal of chlorantraniliprole , objetivou verificar a interação do inseticida clorantraniliprole com adjuvantes comerciais. Foram estudados aspectos como efeito dos adjuvantes na formação dos depósitos, penetração cuticular, por meio de cutículas de maça, cobertura de gotas e efeito da chuva na remoção do inseticida, nas culturas do trigo e milho. Os resultados mostraram que os adjuvantes tem um papel essencial na cobertura de folhas hidrofóbicas, alterando as características da calda de pulverização e melhorando assim a molhabilidade da mesma. Além disso, se pode concluir que os adjuvantes podem melhorar a absorção do inseticida clorantraniliprole.
5

Toxicidade residual de inseticidas utilizados para Spodoptera frugiperda (Lepidoptera: Noctuidae) em milho e Chrysodeixis includens (Lepidoptera: Noctuidae) em soja, e efeitos sobre o predador Doru luteipes (Dermaptera: Forficulidae) / Residual toxicity of insecticides used for Spodoptera frugiperda (Lepidoptera: Noctuidae) in corn and Chrysodeixis includens (Lepidoptera: Noctuidae) on soybean, and effects on the predator Doru luteipes (Dermaptera: Forficulidae)

Silva, Kleber Batista da 13 November 2017 (has links)
O controle químico de pragas, para muitas culturas agrícolas é uma das principais táticas em programas de manejo integrado de pragas (MIP), trazendo benefícios reais e diminuindo as perdas por insetos-praga, além do aumento na produção de alimentos e fibras, proteção de produtos armazenados e proteção de pragas e doenças de seres humanos. O controle de pragas em soja e milho tem sido realizado, em sua maioria, utilizando-se plantas Bt e produtos químicos, este último, além das diversas vantagens citadas, pode ter desvantagens, principalmente quando utilizado de maneira inadequada, com potencial de causar diversos problemas no agroecossistema, além de desequilíbrios ambientais. Devido a importância da cultura da soja e do milho para o Brasil e para o mundo, como base da alimentação animal e humana, reconhecendo o grande uso e papel dos inseticidas como uma das principais táticas usadas para o controle de insetos-praga destas culturas, se faz necessário estudos que tratem da melhor forma de uso dos inseticidas e estudos que avaliem possíveis efeitos adversos destas moléculas em insetos benéficos, para que estejam de acordo com as premissas do MIP. Para viabilizar esta importante tática de controle, realizou-se estudos com os seguintes objetivos: 1) Estudar a toxicidade residual dos inseticidas indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) e teflubenzuron (Nomolt 150®) para C. includens em soja, em ensaio com e sem simulação de chuva; 2) Estudar a toxicidade residual dos inseticidas indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) e teflubenzuron (Nomolt 150®) para S. frugiperda em milho, em ensaio com e sem simulação de chuva; 3) Avaliar efeito letal e subletal de inseticidas recomendados para soja e milho sobre o predador Doru luteipes. Para o primeiro objetivo, teflubenzuron (15 g i. a. ha-1); spinosad (36 g i. a. ha-1); chlorantraniliprole (5, 10 e 20 g i. a. ha-1); indoxacarb (30, 60 e 90 g i. a. ha-1) não tiveram a eficácia afetada quando submetidos à simulação de chuva em todos os tempos avaliados. Quanto a toxicidade residual ao longo do tempo, teflubenzuron, chlorantraniliprole e indoxacarb, nas duas condições, com e sem simulação de chuva, tiveram redução da eficácia após o 5° dia. Diferentemente, os inseticidas spinosad (36 g i. a. ha-1) e indoxacarb (90 g i. a. ha-1), nas duas condições, não tiveram redução da eficácia até 15 dias após aplicação, e em todos os tempos avaliados foram mais eficazes do que os demais inseticidas. Para o segundo objetivo, spinosad (36 g i. a. ha-1) e chlorantraniliprole (10, 20 e 30 g i. a. ha-1) mantiveram a eficácia até o 15º dia após pulverização. Quanto aos efeito da simulação da chuva, spinosad (36 g i. a. ha-1), chlorantraniliprole (10, 20 e 30 g i. a. ha-1) e indoxacarb (90 g i. a. ha-1) mantiveram a eficácia. O inseticida chlorantraniliprole na maior dose utilizada e recomenda para o controle da praga na cultura foi o mais efetivo dentre todos, quanto a toxicidade residual e sob ação da simulação de chuva. Quanto ao terceiro objetivo, ensaio de efeito letal, Tracer, Premio e Avatar foram classificados como nocivos (classe 4), e somente Nomolt foi inócuo (classe 1). No ensaio de efeito subletal apenas o inseticida Nomolt teve parâmetros avaliados. Apesar disso, causou efeitos adversos ao predador, como: aumento do período de pré-oviposição; aumento do período embrionário e diminuição da fecundidade; não sendo, portanto, recomendado para utilização em programas de MIP, pois, altera a capacidade de desenvolvimento e reprodutiva da tesourinha predadora. Os resultados obtidos nesses estudos proveram importantes informações para o refinamento do uso de moléculas inseticidas e classificação desses quanto a seletividade ao predador generalista D. luteipes, agregando informações práticas para o manejo de pragas na cultura da soja e milho. / Chemical pest control for many agricultural crops is one of the main tactics in integrated pest management (IPM) programs, bringing real benefits and decreasing losses by pest insects, as well as increased food and fiber production, protection of stored products and protection of pests and diseases of humans. Pest control in soybean and corn has been mostly carried out using Bt plants and chemical products, for the latter, in addition to the several advantages cited, may have some disadvantages, especially when used improperly, with the potential to cause several problems in the agroecosystem, as well as environmental impacts. Owing to the importance of soybean and corn cultivation to Brazil and to the world, as a basis of animal and human feeding, recognizing the great use and role of insecticides as one of the main tactics used to control insect pests of these crops, it is necessary to study the best use of insecticides and studies that evaluate the possible adverse effects of these chemical molecules on beneficial insects, so that they are in accordance with the IPM premises. To enable this important control tactic, studies were carried out with the following objectives: 1) To study the residual toxicity of insecticides indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) and teflubenzuron (Nomolt 150®) for C. includens in soybeans, with and without rainfastness; 2) To study the residual toxicity of insecticides indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) and teflubenzuron (Nomolt 150®) for S. frugiperda in maize, with and without rainfastness; 3) To evaluate the lethal and sublethal effect of insecticides recommended for soybean and corn on the earwing predator Doru luteipes. For the first objective, teflubenzuron (15 g a. i. ha-1); spinosad (36 g a. i. ha-1); chlorantraniliprole (5, 10 and 20 g a. i. ha-1); indoxacarb (30, 60 and 90 g a. i. ha-1) were not affected when submitted to rainfastness at all evaluated times. Concerning for residual toxicity over time, teflubenzuron, chlorantraniliprole e indoxacarb, under both conditions, with and without rainfastness, had a reduction in efficacy after 5 day. In contrast, the insecticides spinosad (36 g a. i. ha-1) and indoxacarb (90 g a. i. ha-1), in both conditions had no efficacy reduction until 15 days after application and at all times evaluated were more effective than the other insecticides. For the second objective, spinosad (36 g a. i. ha-1) e chlorantraniliprole (10, 20 and 30 g a. i. ha-1) maintained efficacy until the 15th day after spraying. As for the effects of rainfastness, spinosad (36 g a. i. ha-1), chlorantraniliprole (10, 20 and 30 g a. i. ha-1) and indoxacarb (90 g a. i. ha-1) remained effective. The insecticide chlorantraniliprole at the highest dose used and recommended for the control of the pest in the crop was the most effective of all, regarding residual toxicity and under the action of the rainfastness. About the third objective, lethal effect bioassay, Tracer, Premio e Avatar were classified as harmful (class 4), and only Nomolt was innocuous (class 1). In the test of sublethal effect, just the insecticide Nomolt had parameters evaluated. Nevertheless, it caused adverse effects to the predator, such as: increased pre-oviposition period; increase in the embryonic period and decrease in fecundity; therefore, it is not recommended for use in IPM programs, because it modify the developmental and reproductive capacity of predatory earwings. The results obtained in these studies provided important information for the refinement of the use of insecticidal molecules and the classification of these as the selectivity to the generalist predator D. luteipes, adding practical information for pest management in soybean and corn crops.
6

Remoção pela chuva de diferentes formulações de flutriafol aplicada em soja, com e sem a adição de óleo mineral na calda

Oliveira, Maria Aparecida Peres de [UNESP] 11 December 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:35Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-12-11Bitstream added on 2014-06-13T18:42:24Z : No. of bitstreams: 1 oliveira_map_dr_botfca.pdf: 804551 bytes, checksum: 700238b1422e359e397bc2e36724e08e (MD5) / Outros / O presente trabalho teve por objetivos verificar o efeito da remoção pela chuva de diferentes formulações de flutriafol, em condições de laboratório, aplicadas com e sem a adição de óleo na calda de pulverização, assim como verificar a influencia do óleo no espectro de gotas. O experimento considerou dez caldas resultantes da interação de cinco tratamentos contendo o flutriafol (quatro formulações de flutriafol isolado e uma mistura de flutriafol com tebuconazole), todas aplicadas com e sem óleo mineral. As dez caldas foram aplicadas sobre plantas de soja que receberam posteriormente lavagem por chuva simulada em laboratório com quatro intervalos de tempo entre a aplicação e a chuva. As chuvas foram simuladas em duas etapas, sendo uma lâmina inicial de 5 mm seguida de uma lâmina complementar de 15 mm. As coletas foram realizadas com quatro repetições, sendo cada uma delas constituída de um vaso com quatro plantas. A avaliação da concentração de flutriafol nas soluções resultantes da lavagem das plantas foi realizada através da quantificação dos resíduos do fungicida na água pelo método de cromatografia gasosa e espectrometria de massa (GCMS). Após a aplicação das caldas, as plantas foram retiradas do laboratório e deixadas à temperatura ambiente, a espera do tempo decorrido para a simulação da chuva, de acordo com cada tratamento. Após a simulação das lâminas de chuva as plantas foram cortadas dos vasos e lavadas em saco plástico contendo 200 mL de água destilada. Todas as lavagens foram realizadas em 4 intervalos: 0 h (no momento da aplicação), 1 h, 2 h e 48 h após a aplicação. Para o cálculo do percentual extraído, as quantidades de flutriafol nas soluções de lavagem foram comparadas à quantidade total depositada nas plantas, a qual foi representada... / The present study had for objectives to verify the effect of rainfastness of different flutriafol formulations, in laboratory conditions, applied with and without the oil adjuvant in the spray solution, as well as to verify the influence of the oil on the droplet spectrum. The experiment considered ten spray solutions related to five treatments containing flutriafol (four formulations of flutriafol and a flutriafol mixture with tebuconazole), all applied with and without mineral oil. The ten solutions were applied on soybean plants that were washed by simulated rainfall in laboratory with four time intervals between the application and the rainfall. Rainfall was simulated by one initial precipitation of 5 mm followed by a complementary 15 mm rainfall. Each vase with four plants was considered one replication. The washing solutions from the vases were collected and the flutriafol concentration on those solutions was evaluated through the quantification of the residues of the fungicide in the water using the Gas Chromatography-Mass Spectrometry (GC-MS). After the spray application the plants were removed of the laboratory and left to room temperature, the wait of the time elapsed for the simulation of the rain, in agreement with each treatment.After the simulated rain the plants were cut out of the vases and washed by immersion in plastic sack containing 200 mL of distilled water. All of the washing solutions (from the rain and the immersion process) were accomplished in 4 intervals: 0 h (in the moment of the spray application), 1 h, 2 h and 48 h after the application. For the calculation of the flutriafol extracted, the amounts of fungicide in the wash solutions were compared to the total amount deposited in the plants, which was represented by the sum of the amounts of the assets recovered in the washing... (Complete abstract click electronic access below)
7

Remoção pela chuva de diferentes formulações de flutriafol aplicada em soja, com e sem a adição de óleo mineral na calda /

Oliveira, Maria Aparecida Peres de, 1981- January 2009 (has links)
Orientador: Ulissses Rocha Antuniasi / Banca: Otavio Jorge Grigoli Abi Saab / Banca: Marco Antonio Gandolfo / Banca: Edivaldo Domingues Velini / Banca: Wellington P.A.de Carvalho / Resumo: O presente trabalho teve por objetivos verificar o efeito da remoção pela chuva de diferentes formulações de flutriafol, em condições de laboratório, aplicadas com e sem a adição de óleo na calda de pulverização, assim como verificar a influencia do óleo no espectro de gotas. O experimento considerou dez caldas resultantes da interação de cinco tratamentos contendo o flutriafol (quatro formulações de flutriafol isolado e uma mistura de flutriafol com tebuconazole), todas aplicadas com e sem óleo mineral. As dez caldas foram aplicadas sobre plantas de soja que receberam posteriormente lavagem por chuva simulada em laboratório com quatro intervalos de tempo entre a aplicação e a chuva. As chuvas foram simuladas em duas etapas, sendo uma lâmina inicial de 5 mm seguida de uma lâmina complementar de 15 mm. As coletas foram realizadas com quatro repetições, sendo cada uma delas constituída de um vaso com quatro plantas. A avaliação da concentração de flutriafol nas soluções resultantes da lavagem das plantas foi realizada através da quantificação dos resíduos do fungicida na água pelo método de cromatografia gasosa e espectrometria de massa (GCMS). Após a aplicação das caldas, as plantas foram retiradas do laboratório e deixadas à temperatura ambiente, a espera do tempo decorrido para a simulação da chuva, de acordo com cada tratamento. Após a simulação das lâminas de chuva as plantas foram cortadas dos vasos e lavadas em saco plástico contendo 200 mL de água destilada. Todas as lavagens foram realizadas em 4 intervalos: 0 h (no momento da aplicação), 1 h, 2 h e 48 h após a aplicação. Para o cálculo do percentual extraído, as quantidades de flutriafol nas soluções de lavagem foram comparadas à quantidade total depositada nas plantas, a qual foi representada... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract : The present study had for objectives to verify the effect of rainfastness of different flutriafol formulations, in laboratory conditions, applied with and without the oil adjuvant in the spray solution, as well as to verify the influence of the oil on the droplet spectrum. The experiment considered ten spray solutions related to five treatments containing flutriafol (four formulations of flutriafol and a flutriafol mixture with tebuconazole), all applied with and without mineral oil. The ten solutions were applied on soybean plants that were washed by simulated rainfall in laboratory with four time intervals between the application and the rainfall. Rainfall was simulated by one initial precipitation of 5 mm followed by a complementary 15 mm rainfall. Each vase with four plants was considered one replication. The washing solutions from the vases were collected and the flutriafol concentration on those solutions was evaluated through the quantification of the residues of the fungicide in the water using the Gas Chromatography-Mass Spectrometry (GC-MS). After the spray application the plants were removed of the laboratory and left to room temperature, the wait of the time elapsed for the simulation of the rain, in agreement with each treatment.After the simulated rain the plants were cut out of the vases and washed by immersion in plastic sack containing 200 mL of distilled water. All of the washing solutions (from the rain and the immersion process) were accomplished in 4 intervals: 0 h (in the moment of the spray application), 1 h, 2 h and 48 h after the application. For the calculation of the flutriafol extracted, the amounts of fungicide in the wash solutions were compared to the total amount deposited in the plants, which was represented by the sum of the amounts of the assets recovered in the washing... (Complete abstract click electronic access below) / Doutor
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Toxicidade residual de inseticidas utilizados para Spodoptera frugiperda (Lepidoptera: Noctuidae) em milho e Chrysodeixis includens (Lepidoptera: Noctuidae) em soja, e efeitos sobre o predador Doru luteipes (Dermaptera: Forficulidae) / Residual toxicity of insecticides used for Spodoptera frugiperda (Lepidoptera: Noctuidae) in corn and Chrysodeixis includens (Lepidoptera: Noctuidae) on soybean, and effects on the predator Doru luteipes (Dermaptera: Forficulidae)

Kleber Batista da Silva 13 November 2017 (has links)
O controle químico de pragas, para muitas culturas agrícolas é uma das principais táticas em programas de manejo integrado de pragas (MIP), trazendo benefícios reais e diminuindo as perdas por insetos-praga, além do aumento na produção de alimentos e fibras, proteção de produtos armazenados e proteção de pragas e doenças de seres humanos. O controle de pragas em soja e milho tem sido realizado, em sua maioria, utilizando-se plantas Bt e produtos químicos, este último, além das diversas vantagens citadas, pode ter desvantagens, principalmente quando utilizado de maneira inadequada, com potencial de causar diversos problemas no agroecossistema, além de desequilíbrios ambientais. Devido a importância da cultura da soja e do milho para o Brasil e para o mundo, como base da alimentação animal e humana, reconhecendo o grande uso e papel dos inseticidas como uma das principais táticas usadas para o controle de insetos-praga destas culturas, se faz necessário estudos que tratem da melhor forma de uso dos inseticidas e estudos que avaliem possíveis efeitos adversos destas moléculas em insetos benéficos, para que estejam de acordo com as premissas do MIP. Para viabilizar esta importante tática de controle, realizou-se estudos com os seguintes objetivos: 1) Estudar a toxicidade residual dos inseticidas indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) e teflubenzuron (Nomolt 150®) para C. includens em soja, em ensaio com e sem simulação de chuva; 2) Estudar a toxicidade residual dos inseticidas indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) e teflubenzuron (Nomolt 150®) para S. frugiperda em milho, em ensaio com e sem simulação de chuva; 3) Avaliar efeito letal e subletal de inseticidas recomendados para soja e milho sobre o predador Doru luteipes. Para o primeiro objetivo, teflubenzuron (15 g i. a. ha-1); spinosad (36 g i. a. ha-1); chlorantraniliprole (5, 10 e 20 g i. a. ha-1); indoxacarb (30, 60 e 90 g i. a. ha-1) não tiveram a eficácia afetada quando submetidos à simulação de chuva em todos os tempos avaliados. Quanto a toxicidade residual ao longo do tempo, teflubenzuron, chlorantraniliprole e indoxacarb, nas duas condições, com e sem simulação de chuva, tiveram redução da eficácia após o 5° dia. Diferentemente, os inseticidas spinosad (36 g i. a. ha-1) e indoxacarb (90 g i. a. ha-1), nas duas condições, não tiveram redução da eficácia até 15 dias após aplicação, e em todos os tempos avaliados foram mais eficazes do que os demais inseticidas. Para o segundo objetivo, spinosad (36 g i. a. ha-1) e chlorantraniliprole (10, 20 e 30 g i. a. ha-1) mantiveram a eficácia até o 15º dia após pulverização. Quanto aos efeito da simulação da chuva, spinosad (36 g i. a. ha-1), chlorantraniliprole (10, 20 e 30 g i. a. ha-1) e indoxacarb (90 g i. a. ha-1) mantiveram a eficácia. O inseticida chlorantraniliprole na maior dose utilizada e recomenda para o controle da praga na cultura foi o mais efetivo dentre todos, quanto a toxicidade residual e sob ação da simulação de chuva. Quanto ao terceiro objetivo, ensaio de efeito letal, Tracer, Premio e Avatar foram classificados como nocivos (classe 4), e somente Nomolt foi inócuo (classe 1). No ensaio de efeito subletal apenas o inseticida Nomolt teve parâmetros avaliados. Apesar disso, causou efeitos adversos ao predador, como: aumento do período de pré-oviposição; aumento do período embrionário e diminuição da fecundidade; não sendo, portanto, recomendado para utilização em programas de MIP, pois, altera a capacidade de desenvolvimento e reprodutiva da tesourinha predadora. Os resultados obtidos nesses estudos proveram importantes informações para o refinamento do uso de moléculas inseticidas e classificação desses quanto a seletividade ao predador generalista D. luteipes, agregando informações práticas para o manejo de pragas na cultura da soja e milho. / Chemical pest control for many agricultural crops is one of the main tactics in integrated pest management (IPM) programs, bringing real benefits and decreasing losses by pest insects, as well as increased food and fiber production, protection of stored products and protection of pests and diseases of humans. Pest control in soybean and corn has been mostly carried out using Bt plants and chemical products, for the latter, in addition to the several advantages cited, may have some disadvantages, especially when used improperly, with the potential to cause several problems in the agroecosystem, as well as environmental impacts. Owing to the importance of soybean and corn cultivation to Brazil and to the world, as a basis of animal and human feeding, recognizing the great use and role of insecticides as one of the main tactics used to control insect pests of these crops, it is necessary to study the best use of insecticides and studies that evaluate the possible adverse effects of these chemical molecules on beneficial insects, so that they are in accordance with the IPM premises. To enable this important control tactic, studies were carried out with the following objectives: 1) To study the residual toxicity of insecticides indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) and teflubenzuron (Nomolt 150®) for C. includens in soybeans, with and without rainfastness; 2) To study the residual toxicity of insecticides indoxacarb (Avatar®), chlorantraniliprole (Premio®), spinosad (Tracer®) and teflubenzuron (Nomolt 150®) for S. frugiperda in maize, with and without rainfastness; 3) To evaluate the lethal and sublethal effect of insecticides recommended for soybean and corn on the earwing predator Doru luteipes. For the first objective, teflubenzuron (15 g a. i. ha-1); spinosad (36 g a. i. ha-1); chlorantraniliprole (5, 10 and 20 g a. i. ha-1); indoxacarb (30, 60 and 90 g a. i. ha-1) were not affected when submitted to rainfastness at all evaluated times. Concerning for residual toxicity over time, teflubenzuron, chlorantraniliprole e indoxacarb, under both conditions, with and without rainfastness, had a reduction in efficacy after 5 day. In contrast, the insecticides spinosad (36 g a. i. ha-1) and indoxacarb (90 g a. i. ha-1), in both conditions had no efficacy reduction until 15 days after application and at all times evaluated were more effective than the other insecticides. For the second objective, spinosad (36 g a. i. ha-1) e chlorantraniliprole (10, 20 and 30 g a. i. ha-1) maintained efficacy until the 15th day after spraying. As for the effects of rainfastness, spinosad (36 g a. i. ha-1), chlorantraniliprole (10, 20 and 30 g a. i. ha-1) and indoxacarb (90 g a. i. ha-1) remained effective. The insecticide chlorantraniliprole at the highest dose used and recommended for the control of the pest in the crop was the most effective of all, regarding residual toxicity and under the action of the rainfastness. About the third objective, lethal effect bioassay, Tracer, Premio e Avatar were classified as harmful (class 4), and only Nomolt was innocuous (class 1). In the test of sublethal effect, just the insecticide Nomolt had parameters evaluated. Nevertheless, it caused adverse effects to the predator, such as: increased pre-oviposition period; increase in the embryonic period and decrease in fecundity; therefore, it is not recommended for use in IPM programs, because it modify the developmental and reproductive capacity of predatory earwings. The results obtained in these studies provided important information for the refinement of the use of insecticidal molecules and the classification of these as the selectivity to the generalist predator D. luteipes, adding practical information for pest management in soybean and corn crops.
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Controlled Release from Agricultural Spray Deposits

Wang, Fengyan January 2020 (has links)
Copper chlorophyllin (CuChl) is an antioxidant from renewable sources, which has shown as a potential active ingredient in agricultural crop sprays. The major objectives of this thesis are to understand the colloidal and interfacial behaviors of CuChl, and to develop strategies for improving its effectiveness in field applications. In this project, the following three areas are examined and analyzed. In practice, CuChl-based formulations are sprayed directly onto a plant’s foliage. As such, there is a need to understand how CuChl interacts with relevant plant surfaces. To this end, quartz crystal microbalance with dissipation (QCM-D) was used to quantify the adsorption of CuChl aqueous solutions onto four model surfaces: polystyrene, cellulose, pullulan, and silica. The results showed that cellulose adsorbed the highest amount of CuChl, followed by polystyrene and pullulan. In addition, the results also showed that the surfactants, SDS or DTAB, could alter the binding of CuChl to cellulose when used in concentrations above the critical micelle concentration. CuChl is composed of water-soluble and dispersed components, therefore it is not intrinsically rainfast, which limits its field application. To immobilize CuChl on leaves, a polymer combination of CMC (carboxymethyl cellulose) and PAE (polyamidoamine-epichlorohydrin) was designed for use as a spray adjuvant. The release behaviors of CuChl from dried spray deposits were investigated using varied polymer compositions and concentrations and compared with those of a water-soluble dye, brilliant sulfaflavine (BSF). The results indicated that a small amount of CuChl was immediately released upon exposure to water whereas BSF’s release behavior was dependent on the square root of time. The unusual behavior of CuChl was attributed to the presence of particles in the solution. These nanoparticles were coated with CMC:PAE complex, with the result of being immobilized on parafilm. Suspoemulsion is the most complex agricultural formulation that is composed of both dispersed particles and emulsion droplets. The objective of this work is to understand the relationship between the solution properties of suspoemulsions and the resulting dried deposits on hydrophobic surfaces. The results showed that the distribution of polychlorinated Cu (II) phthalocyanine (PG7) particles in dried deposits was related to the extent to which PG7 particles were adsorbed on or entrained in oil droplets. The PG7 particles that mainly ended up in the center (dome) area after drying were bound to the oil/water interface in the suspoemulsion, whereas individually dispersed particles ended up in the annulus. / Thesis / Doctor of Philosophy (PhD) / Agricultural formulations have been developed and widely applied to crops in an effort to maximize yields to keep up with the food demands of the world’s ever-growing population. However, there are still many challenges associated with the application of these formulations, such as huge losses due to spray drift, wash-off, and degradation during spraying. These issues can reduce the formulation’s overall efficacy and pose serious risks to the environment and human health. The primary objective of this thesis is to explore the agricultural application of a new environmentally-friendly active ingredient, copper chlorophyllin (CuChl). To this end, this work begins by determining CuChl’s colloidal and adsorption behaviors, with a particular focus on its binding tendencies for relevant plant surfaces. Next, a polymer combination was designed as a spray adjuvant to enhance CuChl’s rainfastness performance and CuChl’s release from dried deposits was characterized. Finally, the distribution of dispersed particles in dried suspoemulsion deposits was determined.
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Characterization of Organosilicone Surfactants and Their Effects on Sulfonylurea Herbicide Activity

Sun, Jinxia 05 April 1996 (has links)
This research focused on the characterization of organosilicone surfactants and their effects on sulfonylurea herbicide activity. The project included efficacy tests, rainfastness studies in the greenhouse, radiotracer studies on herbicide uptake, fluorescent dye studies on surface deposition, and various measurements of physico-chemical properties. In measuring physico-chemical properties, a logistic dose response relationship was found between adjuvant concentration and contact angle on parafilm. An AsymSigR relationship existed between adjuvant concentration and surface tension for all the adjuvants. The organosilicones, Silwet L-77, Silwet 408, and Sylgard 309, and Kinetic (a blend of an organosilicone with a nonionic surfactant) gave equilibrium surface tension values around 20 dyne/cm and showed great spreading ability on the foliage of velvetleaf. With the conventional adjuvants, Agri-Dex, methylated soybean oil, Rigo oil concentration, and X-77, and Dyne-Amic (a blend of an organosilicone with a crop oil concentrate), surface tension was rarely below 28 dyne/cm and spreading ability was limited on velvetleaf. In addition, the organosilicone surfactant and Kinetic also lowered dynamic surface tension, which may improve droplet retention on leaf surfaces. The differences in physico-chemical properties between Kinetic and Dyne-Amic confirmed that carefully electing a co-adjuvant for an organosilicone blend is critical to avoid antagonism with trisiloxane molecules and retain the unique physico-chemical properties of organosilicone in the blends. Studies involving structurally-related organosilicones showed that the end structure in the trisiloxane hydrophilic group has little or no effect on surface tension, contact angle, spread pattern, herbicide uptake and translocation, and efficacy of primisulfuron on velvetleaf. It may be suggested that there is not a strict requirement to purify the end structure during the synthesis process, which is time consuming and expensive. When 14C-primisulfuron was combined with organosilicones or the blends, the uptake of 14C at 1 or 2 h after herbicide application was significantly higher than when combined with conventional adjuvants in velvetleaf. In the greenhouse, organosilicone surfactants greatly increased the rainfastness of primisulfuron in velvetleaf. The effect was immediate and dramatic, even when simulated rainfall was applied 0.25 h after treatment. In addition, herbicide efficacy on marginally susceptible weed species, velvetleaf and barnyardgrass, was significantly increased. A very complicated relationship exists between herbicides and adjuvants. The enhancement effects of adjuvants are often herbicide specific, weed species specific, and even environment specific. No one type of adjuvant functions well in all circumstances. Therefore, there is a need to understand the properties and functions of each class of adjuvants and locate the 'right' niche for each individual adjuvant. / Ph. D.

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