Resumo A cultura do milho, por sua fácil adaptação aos mais diversos agroecossistemas, se espalha por diferentes regiões do mundo, tornando-se uma das mais importantes culturas agrícolas. Nesta cultura, os insetos-praga se destacam por causar prejuízos tanto no campo quanto nos armazéns. A aplicação de óleos essenciais pode ser uma importante técnica a ser investigada no manejo de insetos devido à sua conhecida atividade inseticida e baixo risco o meio ambiente. O objetivo do deste trabalho foi avaliar o efeito inseticida e repelente de óleos essenciais de capim-limão exótico (Cymbopogon citratus) e capim-limão nativo (Elionurus sp.) para o manejo do gorgulho do milho (Sitophilus zeamais (Mots., 1855, Coleoptera: Curculionidae). A análise química dos óleos feita por CG-MS mostrou que a composição química do capim-limão nativo e exótico é semelhante, entretanto, as espécies exóticas apresentaram maior número de compostos. Os óleos essenciais de capim-limão nativo e exótico têm eficiência na mortalidade do gorgulho do milho, e verifica-se que o aumento na dose aplicada reflete na redução do tempo de exposição do inseto até que ocorra a morte. O óleo essencial de ambas as espécies apresentou capacidade repelente em todos os momentos avaliados. Assim, pode-se afirmar que ambas as espécies possuem capacidade e potencial para serem utilizadas no manejo do gorgulho do milho, podendo ser uma alternativa para a agricultura familiar e produção orgânica.

Abstract Corn crop, due to its easy adaptation to the most diverse agroecosystems, spreads throughout the different regions of the world, making it one of the most important agricultural crops. In this crop, pest insects stand out for causing losses both in the field and in warehouses. The application of essential oils can be an important technique to be investigated in the management of insects due to its known insecticidal activity and low risk to the environment. The objective of the work was to value the insecticide and repellent effect of essential oils of exotic lemongrass (Cymbopogon citratus) and native lemongrass (Elionurus sp.) for the management of maize weevil (Sitophilus zeamais (Mots., 1855, Coleoptera: Curculionidae)). The chemical analysis of the oils made by CG-MS showed that the chemical composition of the native and exotic lemongrass is similar, however, the exotic species presented a greater number of compounds. The essential oils of native and exotic lemon grass have efficiency on maize weevil mortality, and it is verified that the increase in the applied dose reflects in a reduction in the insect's exposure time for death to occur. The essential oil of both species showed repellent capacity at all times evaluated. Thus, it can be said that both species have the capacity and potential to be used in the management of corn weevil, and can be an alternative for smallhorders farmers and organic production.

ABSTRACT Three-dimensional (3D) printing is the construction of a solid structure from a digital model. 3D reconstruction was performed using contrast-enhanced computed tomography scan, and 3D-printed models were built based on the main anatomic structures of the liver. 3D-printed models were used in two patients with indication of surgery; one woman with inherited thrombocytopenia and liver metastases from colorectal adenocarcinoma with no response to chemotherapy, and one man with chronic liver infection and hepatocellular carcinoma. The implementation of 3D printing technology was very useful, as it facilitated the understanding of the spatial relationships among the anatomical structures in both cases. In our experience, the use of 3D-printed models was very useful for preoperative planning and for understanding the anatomic landmarks. The model was built in 7 days, with a cost of 380 dollars which is elevated in our environment.

RESUMEN La impresión de modelos tridimensionales (M3D) implica obtener una estructura sólida y formada a partir de un modelo digital. Para la reconstrucción 3D se utilizó tomografía computarizada contrastada, realizándose impresión de modelos sobre la base de las principales estructuras anatómicas hepáticas. Se utilizaron M3D en dos pacientes con indicación quirúrgica, una mujer con trombocitopenia familiar y metástasis hepática de adenocarcinoma rectal, sin respuesta a quimioterapia, y un hombre con hepatopatía infecciosa crónica y diagnóstico de carcinoma hepatocelular. La aplicación de M3D resultó de gran utilidad, pues permitió un mejor entendimiento de la relación espacial de las estructuras anatómicas en ambos casos. En nuestra experiencia, la aplicación de M3D fue muy útil para planificar la cirugía y dar una aproximación más certera de los reparos anatómicos. El modelo se obtuvo en 7 días y costó 380 dólares, un valor elevado para nuestro medio.

Abstract The exponential advance of information technologies and the increasing use of the Internet in everyday life, especially for the storage of material that may or may not be of a patrimonial nature, coupled with an archaic regulatory system regarding inheritance law, both in Brazil and Spain, has brought constant problems of practical order regarding the destination of the “virtual goods and rights” of the “de whose”. Thus, the objective is to briefly analyze the Spanish and Brazilian regulatory systems regarding the 'digital inheritance', finding that the current rules are innocuous for an adequate practical solution. The theoretical and historical method was used, which consists of consulting works, journal articles, electronic documents, as well as legislation pertinent to the subject in both countries. We also analyzed how digital law emerges as a new branch of law and which assets can be inherited, never leaving aside privacy in the digital age, human dignity, and the rights of personality, intrinsic to the owner of the digital asset, which endure even after his death.

Resumo O exponencial avanço das tecnologias de informação e o uso cada vez maior da internet no cotidiano, principalmente na guarda de material que, pode ou não ter cunho patrimonial, aliado a um arcaico sistema normativo no que concerne o direito sucessório, tanto no Brasil quanto na Espanha, tem trazido constantes problemas de ordem prática quanto a destinação dos “bens e direitos virtuais” do de cujos. Assim, o objetivo é analisar brevemente o sistema normativo espanhol e brasileiro no tocante à ‘herança digital’, constatando que as normas vigentes são inócuas para uma solução prática adequada. Foi utilizado o método teórico e histórico que consiste na consulta de obras, artigos de periódicos, documentos eletrônicos, bem como da legislação pertinente ao tema de ambos os países. Também se analisou como o direito digital surge como um novo ramo do direito e quais são os bens passíveis de serem herdados, nunca deixando de lado a privacidade na era digital, a dignidade da pessoa humana e os direitos da personalidade, intrínsecos ao proprietário do bem digital, que se perduram mesmo após a sua morte.

Abstract Fatty acid synthase (FASN) is the rate-limiting enzyme for the de novo synthesis of fatty acids in the cytoplasm of tumour cells. Many tumour cells express high levels of FASN, and its expression is associated with a poorer prognosis. Cervical cancer is a major public health problem, representing the fourth most common cancer affecting women worldwide. To date, only a few in silico studies have correlated FASN expression with cervical cancer. This study aimed to investigate in vitro FASN expression in premalignant lesions and cervical cancer samples and the effects of a FASN inhibitor on cervical cancer cells. FASN expression was observed in all cervical cancer samples with increased expression at more advanced cervical cancer stages. The FASN inhibitor (orlistat) reduced the in vitro cell viability of cervical cancer cells (C-33A, ME-180, HeLa and SiHa) in a time-dependent manner and triggered apoptosis. FASN inhibitor also led to cell cycle arrest and autophagy. FASN may be a potential therapeutic target for cervical cancer, and medicinal chemists, pharmaceutical researchers and formulators should consider this finding in the development of new treatment approaches for this cancer type.

RESUMO - RACIONAL: Múltiplas são as propostas de reconstrução do trânsito digestivo após as pancreadoduodenectomias. A anastomoses biliar posicionada antes da anastomose gástrica oferece argumentos de evitar refluxo e colangite pós-operatória. OBJETIVOS: apresentar a técnica de continuidade gástrica e biliar com sequência anatômica após pancreatoduodenectomia em portadores de adenocarcinoma de pâncreas e avaliar os resultados em uma série inicial de casos. MÉTODOS: Foram utilizadas duas técnicas, uma com reconstrução em Y de Roux e pancreaticojejunostomia e outra com alça única de jejuno e pancreatogastroanastomose. Em ambos, a anastomose gástrica foi colocada antes da biliar. E análise de dados demográficos, dilatação do ducto de Wirsung e ducto biliar comum, uso de drenagem percutânea e complicações pós-operatórias. RESULTADOS: Foram operados 7 doentes: 4 homens e 3 mulheres, com média de idade de 62 anos. Todos os casos apresentavam dilatação do ducto de Wirsung e ducto biliar comum. Em 4 dos casos foi realizada drenagem biliar externa percutânea. Ocorreram 3 complicações pós-operatórias, 1 esvaziamento gástrico retardado e 2 infecções de ferida operatória. Durante o acompanhamento médio de 12 meses, não foram registrados episódios de colangite. CONCLUSÕES: Porcentagens elevadas de colangite são relatadas nas diferentes reconstruções após pancreatodudenectomias, sendo difícil atribuir de forma absoluta o refluxo como a principal etiologia. As reconstruções gástrica e biliar propostas são mais harmoniosas, além de facilitar o acesso endoscópico posterior. Seguimento tardio e número maior de casos, pode esclarecer se a etiologia da colangite pós-operatória pode ser o refluxo ou a outros fatores não relacionados à ordem das anastomoses.

ABSTRACT - BACKGROUND: Several methods have been proposed for the reconstruction of digestive transit after pancreatoduodenectomy. Biliary anastomosis positioned before gastric anastomosis helps reduce postoperative reflux and cholangitis. AIMS: The objective of this study was to present the anatomical sequence of gastric and biliary continuity after pancreatoduodenectomy in patients with pancreatic tumor and to evaluate the short- and long-term results in an initial series of cases. METHODS: Two techniques were used: one with Roux-en-Y reconstruction and pancreaticojejunostomy and the other with a single jejunal loop and pancreatogastroanastomosis. In both the cases, the gastric anastomosis was placed performed before the biliary one. An analysis of demographic data, Wirsung’s duct and common bile duct dilatation, the use of percutaneous drainage, and postoperative complications was carried out. RESULTS: A total of seven patients (four men and three women), with a mean age of 62 years, underwent surgery. All cases had Wirsung’s duct and common bile duct dilatation. A percutaneous external biliary drainage was performed in four patients. There were three postoperative complications: one related to delayed gastric emptying and two related to wound infections. During a median follow-up of 12 months, no episode of cholangitis was recorded. CONCLUSIONS: Elevated percentages of cholangitis are reported in different reconstructions after pancreatoduodenectomy, and it is difficult to conclude reflux as the main etiology. The proposed gastric and biliary reconstructions show conforming results, facilitating posterior endoscopic access. Late follow-up and large number of cases may help assess whether the etiology of postoperative cholangitis is reflux or other factors unrelated to the order of the anastomoses.

ABSTRACT Caroli’s disease is a rare condition, and its diagnosis requires high level of suspicion. The disease may affect one segment, one lobe or the entire liver, and may result in repeated episodes of cholangitis. The disease can be managed using different therapeutic approaches ranging from medical treatment to liver transplantation. In this paper we report 3 cases with review of the literature and propose a modification of the classification by Alonso-Lej modified by Todani which we believe may be useful to guide treatment.

RESUMEN La enfermedad de Caroli es una enfermedad infrecuente que requiere un alto índice de sospecha para su diagnóstico. Puede afectar un segmento hepático, un lóbulo o todo el hígado; suele generar episodios repetidos de colangitis. Existe una amplia gama de propuestas terapéuticas que oscilan desde el tratamiento médico hasta el trasplante de hígado. En este trabajo presentamos 3 casos, realizamos una revisión de la literatura y proponemos una ampliación de la clasificación de Alonso-Lej modificada por Todani que, a nuestra manera de ver, tiene implicaciones a la hora de seleccionar un tratamiento.

ABSTRACT Since the development of fast-track programs in colorectal surgery with promising results, many centers started with these programs, and improved them. These programs were applied to different organs with the same results observed in colorectal surgery. Liver resections were not excluded from enhanced recovery programs, with a significant reduction in length of hospital stay and costs. Adequate patient information and commitment, multimodal analgesia, fluid therapy and early oral intake are the most important items of these programs.

RESUMEN Desde la aparición de un programa de Fast Track en cirugía colónica con resultados alentadores, muchos centros se abocaron a su aplicación y mejoramiento. El uso de estos programas en diferentes órganos trajo aparejados los mismos resultados que en cirugía colónica. Las resecciones hepáticas no quedaron excluidas de su uso. En ellas se logró una importante reducción de los días de estancia hospitalaria y de los costos. Entre los puntos que componen estos programas, una adecuada información al paciente y un compromiso de parte de este, la analgesia multimodal, la fluidoterapia y un inicio temprano de la alimentación parecen ser los más importantes.

RESUMO Racional: O uso do protocolo Recuperação Otimizada Após Cirurgia (ERAS/ACERTO) com sucesso na cirurgia colorretal favoreceu a aplicação dele em outros órgãos; as ressecções hepáticas não foram excluídas dessa tendência. Alguns autores sugerem que a abordagem laparoscópica é elemento central para a obtenção de melhores resultados. Objetivo: Comparar as ressecções hepáticas laparoscópicas e abertas dentro de um ACERTO para avaliar se existem diferenças entre as duas técnicas. Métodos: Estudo descritivo comparando 80 ressecções hepáticas divididas em dois grupos, as realizadas por laparoscopia e aquelas por laparotomia. Foram analisados dados demográficos, referentes à hepatectomia e ao ACERTO. Resultados: Foram realizadas 47 ressecções por laparotomia e o restante por laparoscopia; houve apenas uma conversão para laparotomia no grupo da laparoscopia. Do total, 17 ressecções foram hepatectomias maiores e em 18 ressecções simultâneas. Não houve diferenças entre os procedimentos quanto ao tempo de internação e número de complicações. Houve maior adesão ao ACERTO (p=0,046) e deambulação mais rápida (p=0,001) na operação aberta. Conclusão: O procedimento, seja laparotômico ou laparoscópico nas ressecções hepáticas, não parece mostrar diferenças em uma avaliação ERAS/ACERTO.

ABSTRACT Background: The use of a successful Enhanced Recovery After Surgery (ERAS) in colorectal surgery favored its application in other organs, and hepatic resections were not excluded from this tendency. Some authors suggest that the laparoscopic approach is a central element to obtain better results. Aim: To compare the laparoscopic vs. open hepatic resections within an ERAS to evaluate if there are any differences between them. Methods: In a descriptive study 80 hepatic resections that were divided into two groups, regarding to whether they were submitted to laparoscopy or open surgery. Demographic data, those referring to the hepatectomy and the ERAS was analyzed. Results: Forty-seven resections were carried out in open surgery and the rest laparoscopically; in the first group there was only one conversion to open surgery. Of the total, 17 resections were major hepatectomies and in 18 simultaneous resections. There were no differences between procedures regarding hospital stay and number of complications. There was a greater adherence to the ERAS (p=0.046) and a faster ambulation (p=0.001) in the open surgery. Conclusion: The procedure, whether open or laparoscopically done in hepatic resections, does not seem to show differences in an ERAS evaluation.

Resumo Objetivos: avaliar a associação entre o consumo alimentar gestacional com diferentes condições clínicas das gestantes (hipertensão, diabete, tabagismo, restrição de crescimento intrauterino e um grupo controle) e os demais fatores associados. Métodos: pesquisa transversal aninhada em estudo de coorte realizado de 2011 a2016 em três hospitais de Porto Alegre (Brasil). Foram analisadas, por um questionário estruturado, as condições sociodemográficas e o pré-natal; e práticas alimentares gestacionais pelo Questionário de Frequência Alimentar (QFA). Para o cálculo do percentual calórico referente ao processamento, os itens alimentares foram categorizados em: in natura ou minimamente processados, processados e ultraprocessados. O teste de Kruskal-Wallis com post-hoc de Dunn comparou o consumo alimentar entre os grupos e a regressão de Poisson, a associação entre as variáveis. Resultados: não houve diferença de consumo calórico entre as 303 mães dos diferentes grupos pesquisados, porém as gestantes diabéticas apresentaram menor valor de contribuição vinda dos alimentos ultraprocessados. Além disso, as gestantes de todos os grupos apresentaram consumo adequado em relação ao percentual de contribuição calórica de macronutrientes no valor energético total. Conclusões: não foi encontrada associação entre consumo alimentar e diferentes condições clínicas gestacionais. Nas gestantes diabéticas, tabagistas e hipertensas foram observadas associações da ingestão energética total com diferentes fatores sociodemográficos entre os grupos.

Abstract Objectives: to evaluate the association between dietary intake during pregnancy and different gestational clinical conditions (hypertensive, diabetics, smokers, having intrauterine growth restriction and a control group) and associated factors. Methods: cross-sectional study nested in a cohort study from 2011 to 2016 that occurred in three hospitals in Porto Alegre (Brazil). Sociodemographic conditions and prenatal were investigated and maternal feeding practices were analyzed by the Food Frequency Questionnaire. To calculate the caloric percentage from food groups, food items were categorized into:unprocessed or minimally processed, processed and ultra-processed foods. The Kruskal-Wallis test with Dunn's post-hoc compared food consumption between the groups and the Poisson regression evaluated the association between the variables. Results: there was no statistical difference in food intake among 303 mothers of different gestational clinical conditions, but diabetic pregnant women had lower caloric contribution value of ultra-processed foods. In addition, pregnant women from all groups showed adequate consumption in relation to the percentage of caloric contribution of macronutrients in the total energy value. Conclusions: there was no difference in energy consumption according to different gestational clinical conditions.In diabetic, smokers and hypertensive pregnant women, associations between total energy intake and different sociodemographic factors were observed between the groups.

Abstract Background: Laparoscopic procedures have gained popularity because they favor a faster recovery. In the same way, the establishment of an enhanced recovery after surgery (ERAS) program in major abdominal surgery has shortened the hospital stay. There are several studies that report the results on ERAS programs applied to open or laparoscopic hepatectomies or comparing one of them with the classic approach but few have compared the results between both within an ERAS program. Objective: To compare the results between open and laparoscopic hepatectomies in the same ERAS program. Method: Thirty-six patients undergoing hepatectomies were enrolled in this study and were either laparoscopically or open in an identical ERAS program. Hospital stay and the number of complications were taken as primary end points. Results: There were no significant differences between both groups in terms of hospital stay or number of complications. The differences were in a shorter time of surgery and an earlier ambulation in favor of open surgery and a better full recovery in favor of the laparoscopic approach. Conclusions: Initial data suggest that there would be no benefits in terms of hospital stay and complication rate of laparoscopic hepatectomies over open ones within an ERAS program.

Resumen Antecedentes: Los procedimientos laparoscópicos ganaron popularidad porque favorecen una recuperación rápida. El establecimiento de programas ERAS (Enhanced Recovery After Surgery) en cirugía mayor abdominal ha acortado la estancia hospitalaria independientemente de la vía de abordaje. Varios trabajos informan los resultados sobre programas ERAS aplicados a hepatectomías abiertas o laparoscópicas, o comparando una de ellas con el abordaje clásico, pero pocos han comparado los resultados entre ambas dentro de un programa ERAS. Objetivo: Comparar, dentro un mismo programa ERAS, los resultados entre hepatectomías abiertas y laparoscópicas. Método: Se incorporaron a este estudio 36 pacientes sometidos a hepatectomías que fueron abordados por vía laparoscópica o abierta dentro de un programa ERAS. Los objetivos primarios fueron la estancia hospitalaria y el número de complicaciones. Resultados: No hubo diferencias significativas entre ambos grupos en cuanto a estancia hospitalaria ni número de complicaciones. Las diferencias radicaron en un menor tiempo de cirugía y una deambulación más precoz a favor de la cirugía abierta, y una recuperación total mejor a favor del abordaje laparoscópico. Conclusiones: Los datos iniciales sugieren que no habría beneficios en cuanto a estancia hospitalaria e índice de complicaciones de las hepatectomías laparoscópicas sobre las abiertas dentro de un programa ERAS.

Background: Background: Fast-track programs in liver surgery offer advantages over traditional perioperative management, particularly in terms of reducing length of hospital stay and hospital costs. Material and methods: We conducted an observational and descriptive analysis of patients undergoing open liver resections as part of an enhanced recovery program. Adherence to the program, full recovery of the patients, complications and length of hospital stay were assessed. Results: A total of 32 liver resections were performed in 30 patients, 27 with cancer. The adherence to the program was 78.1% and full recovery on discharge was 75%. The incidence of complications was 12.5%; most of them were not severe but two patients required rehospitalization. Mean length of hospital stay was 3.4 days and 3.6 days when readmissions were considered. Conclusion: The implementation of an ERP after liver resections is feasible and offers advantages in terms of reducing length of hospital stay and hospital costs. We do not think that ERP improves morbidity in these patients.

Antecedentes: los programas fast-track en cirugía hepática muestran ventajas con respecto al manejo perioperatorio tradicional al favorecer principalmente una disminución de la estancia hospitalaria y, por ende, de los costos hospitalarios. Material y métodos: en un estudio observacional y descriptivo se analizan resecciones hepáticas abiertas dentro de un programa de recuperación rápida, haciendo especial hincapié en la adherencia a este, la recuperación total de los enfermos, la morbilidad y la estancia hospitalaria. Resultados: se realizaron 32 hepatectomías en 30 pacientes, 27 de los cuales fueron oncológicos. La adherencia al programa utilizado fue del 78,1% y la recuperación total al momento del alta del 75%. La morbilidad fue del 12,5% y las complicaciones fueron de baja complejidad, aunque 2 pacientes necesitaron reingresar. La estancia hospitalaria tuvo una media de 3,4 días y, sumando los reingresos, de 3,6 días. Conclusión: la aplicación de un ERP en cirugía hepática no solo es factible sino trae aparejada como principal beneficio una disminución en la estancia hospitalaria y, por ende, de los costos. Pero no estamos convencidos de que un ERP mejore la morbilidad de los pacientes.

Civil construction seeks to increase the useful life of the facades of buildings. Installing a ventilated facade is one way to accomplish this due to aesthetic and technical advantages. Ceramic tiles are the main products used as the covering. To the back face of a tile, a bidirectional screen of glass fiber is adhered using epoxy resin. This set forms a composite for security reasons. During the last decade, there has been an increase in the substitution of composites of synthetic fibers with those of natural fibers. The present work compares the fire-resistant behavior of glass fiber with that of jute fiber applied to ceramics installed in ventilated facade. The following conjoint composites were produced: glazed porcelain tile, epoxy resin, glass fiber and jute fiber screens. In this work, it was verified that the jute fiber did not present advantages regarding the exposure to fire in comparison with the glass fiber.

Resumo: O objetivo deste trabalho foi avaliar a distribuição de populações de arroz-vermelho (Oryza sativa) resistente às imidazolinonas (R-IMI), a frequência dos alelos que conferem resistência às IMI, e a adoção de práticas agronômicas aplicadas ao controle do arroz-vermelho, em estações de cultivo e regiões produtoras de arroz do Estado do Rio Grande do Sul (RS), Brasil. No experimento, 1.008 populações de arroz-vermelho foram avaliadas quanto à resistência às IMI, 760 plantas de arroz-vermelho R-IMI foram genotipadas quanto aos alelos da acetolactato sintase (ALS) que conferem resistência às IMI, e 40 produtores de arroz 'Clearfield' foram entrevistados. As populações de arroz-vermelho R-IMI estavam amplamente distribuídas no RS, desde a época de cultivo em 2006/2007, com maior frequência inicial nas regiões orizícolas da Depressão Central e da Fronteira Oeste. A ocorrência de arroz-vermelho R-IMI variou de 1,6 a 3,5 anos após o lançamento do arroz 'Clearfield'. A mutação Gly654Glu da ALS foi mais frequente nas populações de arroz-vermelho R-IMI, o que indica a ocorrência de fluxo gênico da cultivar de arroz 'Clearfield' para as plantas de arroz-vermelho. A rotação de culturas e o uso de sementes certificadas foram adotados por apenas 30% dos produtores de arroz 'Clearfield' entrevistados, com menores percentagens nas regiões em que o arroz-vermelho R-IMI apareceu mais rápido.

Abstract: The objective of this work was to evaluate the distribution of imidazolinone-resistant (IMI-R) red rice (Oryza sativa) populations, the frequency of alleles conferring resistance to IMI, and the adoption of agronomic practices applied to red rice control, across growing seasons and production regions of the state of Rio Grande do Sul (RS), Brazil. In the experiment, 1,008 red rice populations were screened for resistance to IMI, 760 IMI-R red rice plants were genotyped for the acetolactate synthase (ALS) alleles conferring resistance to IMI, and 40 'Clearfield' rice growers were surveyed. IMI-R red rice populations were widespread throughout RS since the 2006/2007 growing season, with a higher initial frequency in the Depressão Central and Fronteira Sul production regions. The occurrence of IMI-R red rice ranged from 1.6 to 3.5 years after 'Clearfield' rice release. Gly654Glu was the most frequent ALS mutation in IMI-R red rice populations, which shows a gene flow from the most used 'Clearfield' rice cultivars to the red rice plants. Crop rotation systems and certified seed were used by only 30% of the surveyed growers of 'Clearfield' rice, with lower percentages in the production regions where IMI-R red rice appeared faster.

RESUMO: Cyhalofop-butyl destaca-se dentre os herbicidas usados no manejo de populações de capim-arroz resistente às imidazolinonas, mas nem sempre o orizicultor fica satisfeito com o resultado obtido com este herbicida. Objetivou-se avaliar a suscetibilidade de populações de capim-arroz (Echinochloa spp.) ao cyhalofop-butyl e, quantificar o efeito da fenologia da infestante sobre a eficácia do seu controle. Para isto, três experimentos foram realizados em casa de vegetação com delineamento inteiramente casualizado, utilizando-se populações de capim-arroz coletadas na região Sul do Brasil. Em dois experimentos, a suscetibilidade de 156 (safra 2012/13) e 103 (safra 2013/14) populações foram avaliadas frente à aplicação do herbicida cyhalofop-butyl na dose de 360g ha-1. Em outro experimento, em que se arranjaram os tratamentos em esquema bi-fatorial, foram avaliados seis doses do herbicida e cinco estádios fenológicos de populações de E. crus-galli. Foi verificada variação na resposta das populações de capim-arroz ao cyhalofop-butyl, em especial na safra 2013/14, em que 20, das 103 populações testadas, tiveram controle menor que 90%. A eficácia do controle foi inversamente proporcional ao estádio fenológico e, o atraso no controle da infestante contribui diretamente para a diminuição da sua suscetibilidade ao herbicida. Cyhalofop-butyl é uma alternativa eficaz para controlar capim-arroz resistente às imidazolinonas, desde que a aplicação ocorra nos estádios iniciais de desenvolvimento (2 a 4 folhas).

ABSTRACT: Cyhalofop-butyl stands out among the herbicides in the control of imidazolinone-resistant Echinochloa species; but, rice farmers are not always satisfied with the control achieved with this herbicide. The objectives were to evaluate in regional scale the susceptibility of Echinochloa populations to cyhalofop-butyl, and quantify the effect of the weed phenology on its efficacy of control. For this, three trials were carried out under greenhouse conditions with a fully random design, using Echinochloa populations collected in rice fields in the southern region of Brazil. In two trials, the susceptibility level of 156 (2012/13 growth season) and 103 (2013/14 growth season) populations were evaluated with the application of cyhalofop-butyl at 360g ha-1. In other trial, in which treatments were arranged in a bi-factorial design (A = 6 x B = 5), it was evaluated six cyhalofop-butyl rates and five phenological stages of E. crus-galli populations. Echinochloa populations had showed differential susceptibility to cyhalofop-butyl, especially in the 2013/14 growth season, where 20 out of the 103 populations had control lower than 90%. The efficacy of this herbicide was inversely proportional to the phenological stage, and the application timing delay contributed directly to the decrease of susceptibility to the herbicide. Cyhalofop-butyl is an effective alternative to control imidazolinone-resistant Echinochloa populations, as long as the application timing occurs in the early phenological stages (2 to 4 leaves).