Field and greenhouse studies were conducted in 2007 and 2008 to evaluate the foliar efficacy of saflufenacil on horseweed (Conyza canadensis (L.) Cronq.). In the field, saflufenacil applied alone at the lowest rate (25 g/ha) resulted in less control than all other herbicide treatments that included saflufenacil. The addition of glyphosate to 25 g/ha of saflufenacil increased the level of control over either herbicide applied alone. However, the addition of glyphosate to 50 g/ha of saflufenacil or greater was not beneficial because saflufenacil alone provided at least 95% control. Overall, horseweed height at the time of herbicide application had very little effect on the efficacy of saflufenacil applied alone or in combination with glyphosate. Application variables can enhance the foliar activity of saflufenacil. In the greenhouse, saflufenacil combined with glyphosate provided greater control than saflufenacil applied alone on both glyphosate-susceptible and -resistant horseweed populations. Regardless of horseweed population or glyphosate, saflufenacil had greater activity when crop oil concentrate rather than nonionic surfactant was used as the adjuvant. Decreasing light level within 24 hours of herbicide application resulted in greater saflufenacil activity. Applying saflufenacil in a pH 5 spray solution resulted in greater activity than pH 7 or pH 9. Although effects from saflufenacil applied under different temperatures were evident in early timings, there were no lasting effects on the efficacy of saflufenacil. Saflufenacil had significant activity on both glyphosate-susceptible and -resistant horseweed. Under certain conditions when complete control of horseweed is not achieved, such as low application rates, large target weeds, and varying environmental conditions, application variables including glyphosate tank-mixtures, crop oil concentrate, low spray solution pH, and low light level may increase the level of horseweed control from saflufenacil.

Field and greenhouse experiments were conducted in 2008, 2009, and 2010 to evaluate the efficacy of glyphosate combined with other broadleaf herbicides on herbicide-resistant and -susceptible weeds in Illinois. In the field, the addition of lactofen or fomesafen to glyphosate provided the greatest consistency and control of problematic target weeds including common waterhemp and giant ragweed. Applications of glyphosate tank-mixtures at EPOST provided 10% greater control of giant ragweed compared with the same treatments at POST. The addition of a tank-mix herbicide with glyphosate provided the greatest impact on weed control when applied to glyphosate-resistant common waterhemp with control increasing by 67% compared with glyphosate applied alone. The addition of a tank-mix herbicide with glyphosate had little impact on control of PPO-resistant and herbicide-susceptible common waterhemp. Generally, the addition of an adjuvant to herbicide mixtures with glyphosate did not influence weed control 14 DAT compared with no additional adjuvant. However, the addition of PO-HSOC and SO-HSOC to glyphosate tank-mixtures containing fomesafen and cloransulam increased annual morningglory control compared with no additional adjuvant. In the greenhouse, PPO-inhibiting herbicides (fomesafen, lactofen, flumiclorac, fluthiacet) applied with glyphosate resulted in additive and antagonistic responses depending on the PPO-inhibitor used and the common waterhemp biotype. Generally, glyphosate tank-mixtures applied to PPO-resistant and herbicide-susceptible common waterhemp biotypes resulted in a greater frequency of antagonism than that of a glyphosate-resistant biotype. The efficacy of glyphosate tank-mixtures was also influenced by environmental conditions shortly before and after the herbicide application. Glyphosate tank-mixtures usually resulted in greater efficacy on common waterhemp when applied at 24 C with 75% RH than at 32 C with 40% RH, regardless of tank-mix herbicide or common waterhemp biotype. Although this research supports an improvement in control of glyphosate-resistant common waterhemp with the addition of PPO-inhibiting herbicides to glyphosate, the overall herbicide efficacy was still somewhat variable with evidence for environmental conditions that may alter efficacy of the tank mixtures. Thus, the use of preemergence, soil residual herbicides are still justified to reduce reliance on these postemergence herbicide mixtures for weed control in soybean and ultimately deter further selection of common waterhemp populations resistant to glyphosate and PPO-inhibiting herbicides.

Field and greenhouse experiments were conducted to determine barnyardgrass control as affected by glufosinate and graminicide tank-mixtures, application timing of tank-mixtures of graminicides plus glufosinate and application time of day of tank-mixtures of glufosinate and clethodim. When increased rates of graminicide were tank-mixed with glufosinate, barnyardgrass control was unaffected by quizalofop-P plus glufosinate; however, clethodim plus glufosinate control in the field indicated the potential for reduced barnyardgrass control. When evaluating increasing glufosinate rates tank-mixed with graminicides, barnyardgrass control was not negatively affected by the combination of glufosinate and graminicides. The difference in soybean yield among the graminicides may indicate that the cyclohexanedione herbicides had a slight yield advantage over the aryloxyphenoxypropionate herbicides due to potential increased levels of barnyardgrass control. Applications of glufosinate alone provide variable control throughout the growing season in both field and greenhouse experiments. Although barnyardgrass control in the field was not affected by glufosinate application timing, data from the greenhouse indicates potential exists for reduced control if glufosinate is applied 1 or 3 d before graminicides. Clethodim was unaffected by application time of day; however, glufosinate applications at midnight reduced barnyardgrass control compared to applications made at noon and 6 P.M. Applications at 6 A.M. also reduced barnyardgrass efficacy compared to applications at 6 P.M. Environmental factors such as temperature and light at the time of application are likely responsible for the time of day effects observed in these studies. For maximum benefit from incorporating graminicides into a glufosinate weed control system, fluazifop-P, quizalofop-P, clethodim and sethoxydim should be applied with glufosinate at 594 or 890 g ai ha-1. Sequential treatments of glufosinate should be applied 7 d prior to a graminicide application or 1, 3 or 7 d after a graminicide application. To optimize barnyardgrass efficacy with tank mixtures of glufosinate and clethodim, applications should be made at noon or early evening to avoid potential time of day effects.

Submitted by JAQUELINE FRANCIOSI DELLA VECHIA null (jaque_dellavechia@hotmail.com) on 2017-09-15T18:50:38Z No. of bitstreams: 1 dellavechia_jf_me_jabo.pdf: 2153516 bytes, checksum: d1e26e0ce1d7a5b2127705dc341206d5 (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-19T17:35:03Z (GMT) No. of bitstreams: 1 dellavechia_jf_me_jabo.pdf: 2153516 bytes, checksum: d1e26e0ce1d7a5b2127705dc341206d5 (MD5) / Made available in DSpace on 2017-09-19T17:35:03Z (GMT). No. of bitstreams: 1 dellavechia_jf_me_jabo.pdf: 2153516 bytes, checksum: d1e26e0ce1d7a5b2127705dc341206d5 (MD5) Previous issue date: 2017-07-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Com o aumento da incidência de insetos e ácaros vetores de doenças viróticas e bacterianas na citricultura brasileira, a combinação de produtos fitossanitários tem sido uma prática comum entre os citricultores, a fim de manter a capacidade operacional e a viabilidade econômica da cultura. Entretanto, é desconhecido o efeito da interação destes produtos sobre as espécies alvo. Neste contexto, o objetivo deste trabalho foi avaliar a interação entre inseticida e acaricida quanto às características físicas, compatibilidade das misturas e o efeito biológico sobre o ácaro Brevipalpus yothersi e o inseto Diaphorina citri. Experimentos foram conduzidos no Laboratório de Acarologia e no Núcleo de Estudo e Desenvolvimento em Tecnologia de Aplicação da UNESP, Câmpus de Jaboticabal. Os tratamentos foram constituídos da combinação do acaricida espirodiclofeno com os inseticidas lambda-cialotrina+tiamethoxam, fosmete e imidacloprido, um a um, além de cada produto isolado. Foram determinadas características de tensão superficial, ângulo de contato, e diâmetro de gotas das caldas. A eficiência de controle dos produtos isolados e em mistura foram determinados para B. yothersi e D. citri. Também foram realizadas avaliações de compatibilidade física das combinações, bem como do pH e condutividade elétrica das caldas. A combinação dos inseticidas lambda-cialotrina + thiametoxam, fosmete e imidacloprido com o acaricida espirodiclofeno interfere na cobertura do alvo, uma vez que reduz a tensão superficial das caldas, consequentemente o ângulo de contato das gotas formadas com a superfície da folha de laranja, aumentam o DMV, diminuem a % de gotas < 100 μm e o SPAN. A eficiência dos inseticidas lambda-cialotrina + thiametoxam, fosmete e imidacloprido utilizados no controle de D. citri não é afetada pela adição de espirodiclofeno. No entanto, a combinação de espirodiclofeno com fosmete e imidacloprido comprometem a eficiência do acaricida no controle de B. yothersi. / With the increase of the incidence of insects and mites vectors of viral and bacterial diseases in brazilian citriculture, the combination of pesticides has been a common practice among citrus growers in order to maintain the operating capacity and economic viability of the crop. However, the effect of the interaction of these products on target species is unknown. In this context, the objective of this work was to evaluate the interaction between the insecticide and the acaricide regarding the physical characteristics, the compatibility of the mixtures and the biological effect on the Brevipalpus yothersi mite and the Diaphorina citri insect. The experiments were conducted at the Laboratory of Acarology and at the Nucleus of Study and Development in Application Technology of UNESP, Jaboticabal Campus, SP, Brazil. The treatments consisted of the combination of the spirodiclofen acaricide with the lambda-cyhalothrin + thiamethoxam, phosmet and imidacloprid insecticides, one by one, in addition to each isolated product. Characteristics of surface tension, contact angle, and diameter of droplets were determined. The control efficiency of the isolated and mixture products were determined for B. yothersi and D. citri. It were also carried out physical compatibility evaluations of the combinations, as well as the pH and electrical conductivity of the spraying liquids. The combination of the lambda-cyhalothrin + thiametoxam, phosmet and imidacloprid insecticides with the spirodiclofen acaricide interfer on the coverage of the target, since it reduces the surface tension of the spraying liquid and, consequently, the contact angle of the droplets formed with the surface of the orange leaf, increases the VMD, decreases the % of droplets <100 μm and the SPAN. The efficiency of the lambdacyhalothrin + thiametoxam, phosmet and imidacloprid insecticides used in the control of D. citri was not affected by the addition of spirodiclofen. However, the combination of spirodiclofen with phosmet and imidacloprid compromises the efficiency of the acaricide in the control of B. yothersi. / CNPq: 134528/2015-8

Na literatura existe um consenso que os herbicidas glifosato (Gli) e 2,4-D interagem antagonicamente quando aplicados em combinação. No entanto, as bases bioquímicas e fisiológicas destes antagonismos são desconhecidas. Utilizou-se espectrometria de Ressonância Magnética Nuclear (RMN) para a caracterização de moléculas de Gli e 2,4-D em várias formulações analíticas, preparadas de maneira que os herbicidas fossem obtidos sem os ingredientes inertes das formulações comerciais. Não foram encontradas alterações significativas na conformação atômica do herbicida nos espectros de RMN entre as formulações analíticas de Gli isopropilamina, dimetilamina, potássio ou amônio; 2,4-D Dimetilamina ou colina, quando analisadas separadamente ou em mistura. Avaliando também formulações comerciais dos herbicidas, não foram encontradas diferenças significativas entre os espectros de RMN para a mistura entre Gli e 2,4-D. A formulação comercial de Gli amoníaco apresentou alterações na conformação molecular do Gli, principalmente na região P da molécula que mostrou maior deslocamento químico, mas isso foi atribuído aos maiores teores de Na encontrados nessa formulação. Aplicando-se as diferentes formulações comerciais na espécie modelo de tomate Micro-Tom (MT), foram estudados os padrões de absorção dos herbicidas. A absorção de Gli radiomarcado pelas plantas de MT foi reduzida somente para a formulação Gli sal de amônio, independentemente da presença de 2,4-D. Neste trabalho, não se observou efeito antagônico na absorção entre Gli e 2,4-D. Por meio de um ensaio fatorial para determinar o efeito antagônico dos herbicidas em plantas de MT, observou-se que a dose de maior antagonismo para 2,4-D foi: 35 g i.a. ha-1 - 0,65 mM e para Gli, 70 g g i.a. ha-1 - 1,7 mM. A translocação do Gli radiomarcado foi significativamente reduzida em MT, quando aplicado com 2,4-D. Experimentos utilizando o marcador molecular GUS no gene DR5 do MT, mostraram que o Gli reduz a resposta de expressão gênica pelas vias de sinalização do 2,4-D. Os ensaios de quantificação de espécies reativas de oxigênio (EROs) induzidas pela atuação do 2,4-D, apresentaram menor produção na presença do Gli. O acúmulo de ácido chiquímico causado pelo Gli no MT foi maior quando aplicado sem mistura com 2,4-D. A interferência do 2,4-D na atuação do Gli foi confirmada nos mutantes insensíveis à auxina diageotropica (dgt) e Never ripe (Nr), em que a produção de EROs foi menor e a translocação do Gli foi mantida independente da aplicação com o 2,4-D. O acúmulo de ácido chiquímico na aplicação de Gli e a mistura dos herbicidas, foram semelhantes. O mutante yellow-green2 (yg2), menos sensível ao Gli, apresentou menor translocação do herbicida. O acúmulo de ácido chiquímico para este mutante foi menor quando aplicado com Gli, mas na mistura de Gli + 2,4-D, a quantidade do ácido aumentou. A insensibilidade ao Gli proporcionou o reestabelecimento da produção de EROs pelo 2,4-D na aplicação da mistura dos herbicidas. Neste trabalho, em contraposição ao conhecimento atual, não se observou qualquer efeito antagônico entre Gli e 2,4-D a nível químico, mas o antagonismo ocorreu por fatores da inter-relação dos mecanismos que cada herbicida induz nos níveis fisiológicos, bioquímicos e genéticos na biologia do organismo vegetal. / A consensus exists in literature that the herbicides glyphosate and 2,4-D interact antagonistically when applied in combination. However, the biochemical and physiological basis of this antagonism are unknown. It was used Nuclear Magnetic Resonance (NMR) spectrometry to characterize the molecules of glyphosate and 2,4-D prepared with high purity analytical compounds without the commercial formulations inert ingredients. No changes in atomic herbicide conformation ware found in NMR spectra of glyphosate formulations isopropylamine, dimethylamine, potassium or ammonium and 2,4-D dimethylamine or choline, when evaluated separately or in mixture. Analysing also the commercial herbicides formulations, no differences in NMR spectra for the mixture between glyphosate and 2,4-D ware found in chemical shift. The ammonium salt glyphosate formulations, presented changes in molecular conformation in P region of glyphosate showing higher chemical shift, which was attributed to higher levels of Na found in its composition. It was applied different commercial formulations in tomato cultivar Micro-Tom (MT) to study the pattern of herbicide absorption. The absorption of radiolabeled glyphosate by MT was reduced in the ammonium salt formulation, regardless of the 2,4-D\'s presence. In this work, no antagonistic effect in plant absorption was observed between glyphosate and 2,4-D. Factor assay was conducted using different concentrations of 2,4-D and glyphosate to determine the antagonistic effect on tomato plants. It was observed that the dose of greater antagonism to 2,4-D form 35 g a.i. ha-1 - 0.65 mM and for glyphosate, 70 g a.i. ha-1 - 1.7 mM. Assays using molecular reporter GUS in MT`s DR5 gene, showed that the glyphosate reduces gene expression responses through signalling pathways of the 2,4-D. The absorption of radiolabeled glyphosate was significantly reduced in MT, when it was applied with 2,4-D. In trials that it was quantified production of reactive oxygen species (ROS) on MT induced by 2,4-D performance, lower production were found when 2,4-D ware applied with glyphosate. The shikimic acid accumulation affected by glyphosate action in MT was higher when applied without 2,4-D mixture. The interference of 2,4-D in glyphosate`s actions was confirmed in auxin insensitive mutants diageotropica (dgt) and Never ripe (Nr), which ROS production was lower. In those mutants, glyphosate translocation was maintained regardless 2,4-D application and shikimic acid accumulation between glyphosate treatment and herbicide mixture were similar. The yellow-green2 (yg2) mutant was less sensitive to glyphosate, presenting low translocation to the herbicide. The shikimic acid accumulation for yg2 mutant was lower when applied with glyphosate, but when it was treated with glyphosate + 2,4-D, the amount of acid was increased. The insensitivity of glyphosate provided reestablishment of ROS production by 2,4-D, when the mixture of herbicides were applied. In this paper it was show that, in contrast to current knowledge, there was no antagonistic effect between glyphosate and 2,4-D in chemical level, but the antagonism occurred by factors of the interrelationship of the mechanisms that each herbicide induces in the physiological, biochemical and genetic levels in the biology of the plant organism.

Na literatura existe um consenso que os herbicidas glifosato (Gli) e 2,4-D interagem antagonicamente quando aplicados em combinação. No entanto, as bases bioquímicas e fisiológicas destes antagonismos são desconhecidas. Utilizou-se espectrometria de Ressonância Magnética Nuclear (RMN) para a caracterização de moléculas de Gli e 2,4-D em várias formulações analíticas, preparadas de maneira que os herbicidas fossem obtidos sem os ingredientes inertes das formulações comerciais. Não foram encontradas alterações significativas na conformação atômica do herbicida nos espectros de RMN entre as formulações analíticas de Gli isopropilamina, dimetilamina, potássio ou amônio; 2,4-D Dimetilamina ou colina, quando analisadas separadamente ou em mistura. Avaliando também formulações comerciais dos herbicidas, não foram encontradas diferenças significativas entre os espectros de RMN para a mistura entre Gli e 2,4-D. A formulação comercial de Gli amoníaco apresentou alterações na conformação molecular do Gli, principalmente na região P da molécula que mostrou maior deslocamento químico, mas isso foi atribuído aos maiores teores de Na encontrados nessa formulação. Aplicando-se as diferentes formulações comerciais na espécie modelo de tomate Micro-Tom (MT), foram estudados os padrões de absorção dos herbicidas. A absorção de Gli radiomarcado pelas plantas de MT foi reduzida somente para a formulação Gli sal de amônio, independentemente da presença de 2,4-D. Neste trabalho, não se observou efeito antagônico na absorção entre Gli e 2,4-D. Por meio de um ensaio fatorial para determinar o efeito antagônico dos herbicidas em plantas de MT, observou-se que a dose de maior antagonismo para 2,4-D foi: 35 g i.a. ha-1 - 0,65 mM e para Gli, 70 g g i.a. ha-1 - 1,7 mM. A translocação do Gli radiomarcado foi significativamente reduzida em MT, quando aplicado com 2,4-D. Experimentos utilizando o marcador molecular GUS no gene DR5 do MT, mostraram que o Gli reduz a resposta de expressão gênica pelas vias de sinalização do 2,4-D. Os ensaios de quantificação de espécies reativas de oxigênio (EROs) induzidas pela atuação do 2,4-D, apresentaram menor produção na presença do Gli. O acúmulo de ácido chiquímico causado pelo Gli no MT foi maior quando aplicado sem mistura com 2,4-D. A interferência do 2,4-D na atuação do Gli foi confirmada nos mutantes insensíveis à auxina diageotropica (dgt) e Never ripe (Nr), em que a produção de EROs foi menor e a translocação do Gli foi mantida independente da aplicação com o 2,4-D. O acúmulo de ácido chiquímico na aplicação de Gli e a mistura dos herbicidas, foram semelhantes. O mutante yellow-green2 (yg2), menos sensível ao Gli, apresentou menor translocação do herbicida. O acúmulo de ácido chiquímico para este mutante foi menor quando aplicado com Gli, mas na mistura de Gli + 2,4-D, a quantidade do ácido aumentou. A insensibilidade ao Gli proporcionou o reestabelecimento da produção de EROs pelo 2,4-D na aplicação da mistura dos herbicidas. Neste trabalho, em contraposição ao conhecimento atual, não se observou qualquer efeito antagônico entre Gli e 2,4-D a nível químico, mas o antagonismo ocorreu por fatores da inter-relação dos mecanismos que cada herbicida induz nos níveis fisiológicos, bioquímicos e genéticos na biologia do organismo vegetal. / A consensus exists in literature that the herbicides glyphosate and 2,4-D interact antagonistically when applied in combination. However, the biochemical and physiological basis of this antagonism are unknown. It was used Nuclear Magnetic Resonance (NMR) spectrometry to characterize the molecules of glyphosate and 2,4-D prepared with high purity analytical compounds without the commercial formulations inert ingredients. No changes in atomic herbicide conformation ware found in NMR spectra of glyphosate formulations isopropylamine, dimethylamine, potassium or ammonium and 2,4-D dimethylamine or choline, when evaluated separately or in mixture. Analysing also the commercial herbicides formulations, no differences in NMR spectra for the mixture between glyphosate and 2,4-D ware found in chemical shift. The ammonium salt glyphosate formulations, presented changes in molecular conformation in P region of glyphosate showing higher chemical shift, which was attributed to higher levels of Na found in its composition. It was applied different commercial formulations in tomato cultivar Micro-Tom (MT) to study the pattern of herbicide absorption. The absorption of radiolabeled glyphosate by MT was reduced in the ammonium salt formulation, regardless of the 2,4-D\'s presence. In this work, no antagonistic effect in plant absorption was observed between glyphosate and 2,4-D. Factor assay was conducted using different concentrations of 2,4-D and glyphosate to determine the antagonistic effect on tomato plants. It was observed that the dose of greater antagonism to 2,4-D form 35 g a.i. ha-1 - 0.65 mM and for glyphosate, 70 g a.i. ha-1 - 1.7 mM. Assays using molecular reporter GUS in MT`s DR5 gene, showed that the glyphosate reduces gene expression responses through signalling pathways of the 2,4-D. The absorption of radiolabeled glyphosate was significantly reduced in MT, when it was applied with 2,4-D. In trials that it was quantified production of reactive oxygen species (ROS) on MT induced by 2,4-D performance, lower production were found when 2,4-D ware applied with glyphosate. The shikimic acid accumulation affected by glyphosate action in MT was higher when applied without 2,4-D mixture. The interference of 2,4-D in glyphosate`s actions was confirmed in auxin insensitive mutants diageotropica (dgt) and Never ripe (Nr), which ROS production was lower. In those mutants, glyphosate translocation was maintained regardless 2,4-D application and shikimic acid accumulation between glyphosate treatment and herbicide mixture were similar. The yellow-green2 (yg2) mutant was less sensitive to glyphosate, presenting low translocation to the herbicide. The shikimic acid accumulation for yg2 mutant was lower when applied with glyphosate, but when it was treated with glyphosate + 2,4-D, the amount of acid was increased. The insensitivity of glyphosate provided reestablishment of ROS production by 2,4-D, when the mixture of herbicides were applied. In this paper it was show that, in contrast to current knowledge, there was no antagonistic effect between glyphosate and 2,4-D in chemical level, but the antagonism occurred by factors of the interrelationship of the mechanisms that each herbicide induces in the physiological, biochemical and genetic levels in the biology of the plant organism.