ABSTRACT: In recent years, the emergence of resistant pathogens has complicated the treatment of bacterial infections in livestock production as well as in the medical field, due to the development of resistance mechanisms by microorganisms. The objective of this study was to delineate the antimicrobial resistance profile of Salmonella spp. strains isolated from bivalve mollusks (oysters and mussels) and from estuarine environment water of two regions of Bahia, Brazil. Twenty-seven strains, 12 isolated from bivalve mollusks and 15 from estuarine water, were tested. Eight antimicrobial agents (phenicol, beta-lactams, tetracyclines, quinolones and fluoroquinolones classes) were used for a susceptibility test, Minimum Inhibitory Concentration (MIC) and extended-spectrum beta-lactamases (ESBLs) production. Isolates showed high susceptibility to the classes of antimicrobial agents tested, with resistance only to nalidixic acid (27%), ampicillin (25%) and tetracycline (25%). Bacterial resistance was of chromosomal origin and the multidrug resistance index (MAR) among isolates of shellfish (mussels in natura) was 0.25. The MIC was found to be 100 µg/mL, 500 µg/mL and 350 µg/mL to nalidixic acid, ampicillin and tetracycline, respectively. None of the isolates presented ESBLs production. The presence of multidrug-resistant and high MIC Salmonella spp. is being conveyed in extraction areas of bivalve mollusks in the State of Bahia, Brazil. | RESUMO: Nos últimos anos o surgimento de patógenos resistentes tem dificultado o tratamento de infecções bacterianas, tanto na produção animal como na área médica, em decorrência do desenvolvimento de mecanismos de resistência pelos micro-organismos. O objetivo deste estudo foi traçar o perfil de resistência antimicrobiana em cepas de Salmonella spp. isoladas de moluscos bivalves (ostras e sururu) e da agua de áreas estuarinas em duas regiões da Bahia, Brasil. Um total de 27 cepas previamente isoladas foram testadas, sendo 12 provenientes de moluscos bivalves e 15 de amostras de água. Para o teste de suscetibilidade foram utilizados oito agentes antimicrobianos (classes fenicóis, betalactâmicos, tetraciclina, quinolonas e fluoroquinolonas), Concentração Inibitória Mínima (CIM) e a produção de Betalactamases de Espectro Ampliado (ESBL). Os isolados apresentaram alta suscetibilidade as classes de antimicrobianos testadas, com resistência apenas ao ácido nalidíxico (27%), ampicilina (25%) e tetraciclina (25%). A resistência bacteriana era de origem cromossômica e o índice de multirresistência (MAR) entre os isolados de molusco (sururu in natura) foi de 0,25. A CIM encontrada foi de 100 µg/mL, 500 µg/mL e 350 µg/mL para o ácido nalidixíco, ampicilina e tetraciclina, respectivamente. Nenhum dos isolados apresentou produção de ESBL. A presença de Salmonella spp. multirresistente e com elevada CIM está sendo veiculada em áreas de extração de moluscos bivalves no Estado da Bahia, Brasil.

In recent years, the emergence of resistant pathogens has complicated the treatment of bacterial infections in livestock production as well as in the medical field, due to the development of resistance mechanisms by microorganisms. The objective of this study was to delineate the antimicrobial resistance profile of Salmonella spp. strains isolated from bivalve mollusks (oysters and mussels) and from estuarine environment water of two regions of Bahia, Brazil. Twenty-seven strains, 12 isolated from bivalve mollusks and 15 from estuarine water, were tested. Eight antimicrobial agents (phenicol, beta-lactams, tetracyclines, quinolones and fluoroquinolones classes) were used for a susceptibility test, Minimum Inhibitory Concentration (MIC) and extended-spectrum beta-lactamases (ESBLs) production. Isolates showed high susceptibility to the classes of antimicrobial agents tested, with resistance only to nalidixic acid (27%), ampicillin (25%) and tetracycline (25%). Bacterial resistance was of chromosomal origin and the multidrug resistance index (MAR) among isolates of shellfish (mussels in natura) was 0.25. The MIC was found to be 100 μg/mL, 500 μg/mL and 350 μg/mL to nalidixic acid, ampicillin and tetracycline, respectively. None of the isolates presented ESBLs production. The presence of multidrug-resistant and high MIC Salmonella spp. is being conveyed in extraction areas of bivalve mollusks in the State of Bahia, Brazil.

RESUMO: A alface é uma das hortaliças folhosas mais produzidas e consumidas no Brasil. A colheita ocorre no período em que a planta atinge o crescimento vegetativo máximo, as folhas ainda estão tenras e sem indícios de pendoamento. Após este período, a planta é considerada inadequada para a comercialização, perdendo-se um alimento rico em vitaminas, sais minerais e composto bioativos, como os carotenóides. Desta forma, este trabalho teve o objetivo de avaliar a qualidade com base em mudanças físico-químicas em uma cultivar de alface roxa durante três idades diferentes. O trabalho foi desenvolvido em uma horta comunitária urbana no município de Sete Lagoas -MG. O delineamento experimental foi inteiramente ao acaso com três repetições sendo os tratamentos os três estádios de desenvolvimento (20, 30 e 40 dias após transplantio - DAT). Aos 40 DAT, a concentração de carotenóides totais e o teor de sólidos solúveis totais foram significativamente superiores, o pH foi menor; e a alface se tornou mais escura, apresentando menores valores do parâmetro b* (incremento da cor amarela) e maiores valores do parâmetro a* (incremento da coloração vermelha), diferindo significativamente das duas primeiras colheitas. A acidez titulável foi igual estatisticamente nas três épocas de avaliação. Considerando o alto conteúdo de carotenóides observado aos 40 DAT, pode-se considerar a colheita nesta idade. | ABSTRACT: Lettuce is one of the most produced and consumed leafy vegetables in Brazil. It is harvested when the plant reaches full vegetative growth and the leaves are still tender and there are no signs of bolting. The plant is unsuitable for commercialization after this period, thus, a food that is rich in vitamins, minerals and bioactive compounds such as carotenoid is lost. Therefore, the objective of this work was to assess the purple lettuce quality based on physical-chemical characteristics, in three different ages. The experiment was conducted in an urban community garden in Sete Lagoas MG, Brazil. A completely randomized experimental design was used with three replications. The treatments consisted of three development stages (20, 30 and 40 days after transplanting - DAT). The treatment with 40 DAT presented total carotenoids concentration and soluble solids content significantly higher, lower pH, and darker lettuce, with lower values of the parameter b* (increase in yellow color), and higher values of the parameter a* (increase in red color), compared to the first two treatments. The titratable acidity was statistically equal for the three evaluation periods. Considering the high concentration of carotenoids found at 40 DAT, the harvest can take place at this age.

Lettuce is one of the most produced and consumed leafy vegetables in Brazil. It is harvested when the plant reaches full vegetative growth and the leaves are still tender and there are no signs of bolting. The plant is unsuitable for commercialization after this period, thus, a food that is rich in vitamins, minerals and bioactive compounds such as carotenoid is lost. Therefore, the objective of this work was to assess the purple lettuce quality based on physical-chemical characteristics, in three different ages. The experiment was conducted in an urban community garden in Sete Lagoas MG, Brazil. A completely randomized experimental design was used with three replications. The treatments consisted of three development stages (20, 30 and 40 days after transplanting - DAT). The treatment with 40 DAT presented total carotenoids concentration and soluble solids content significantly higher, lower pH, and darker lettuce, with lower values of the parameter b* (increase in yellow color), and higher values of the parameter a* (increase in red color), compared to the first two treatments. The titratable acidity was statistically equal for the three evaluation periods. Considering the high concentration of carotenoids found at 40 DAT, the harvest can take place at this age.

ABSTRACT: The feeding frequencies on pacamã Lophiosilurus alexandri larviculture were evaluated. In the first phase, 10 days of active feeding, larvae with nine days post hatching (13.5 ± 0.7 mm) were stocked at density of 10 larvae L-1 in 5-L tanks each. The experimental treatments were: F2T (feeding 8h00 and 17h00); F2M (feeding 8h00 and 12h30); F3 (feeding 8h00, 12h30 and 17h00); and F4 (feeding 8h00, 11h00, 14h00 and 17h00). During this phase Artemia nauplii were used as food. In the second phase, during 15 days, juveniles were restocked in 20-L tanks at density of 2.2 juveniles L-1, and kept the same feeding frequencies of the first phase. Commercial dry diet containing 40% crude protein was used as food. No effect of feeding frequency on growth and survival, during both phases, was observed. However, survival decreases from the first to the second phase, showing the importance of the type of food. During the L. alexandri larviculture should be recommended twice a day feeding frequency. | RESUMO: Objetivou-se avaliar diferentes frequências alimentares na larvicultura de pacamã Lophiosilurus alexandri. Na primeira fase, com duração de 10 dias, larvas com nove dias pós-eclosão (13,5 ± 0,7 mm) foram estocadas na densidade de 10 larvas L-1 em tanques com 5 L cada. Os tratamentos experimentais foram: F2T (alimentação as 8h00 e 17h00); F2M (alimentação as 8h00 e 12h30); F3 (alimentação as 8h00, 12h30 e 17h00); e F4 (alimentação as 8h00, 11h00, 14h00 e 17h00). Durante esta fase foram utilizados náuplios de Artemia como alimento. Na segunda fase, com duração de 15 dias, os juvenis foram estocados em tanques com 20 L na densidade de 2,2 juvenis L-1, sendo mantidas as mesmas frequências alimentares da primeira fase. A alimentação consistiu no fornecimento de ração comercial contendo 40% de proteína bruta. Durante as duas fases, as diferentes frequências alimentares não afetaram o desempenho e sobrevivência. No entanto, a sobrevivência diminui da primeira para a segunda fase, mostrando a importância do tipo de alimento. Durante a larvicultura do pacamã pode ser recomendada a frequência alimentar de duas vezes ao dia.

The feeding frequencies on pacamã Lophiosilurus alexandri larviculture were evaluated. In the first phase, 10 days of active feeding, larvae with nine days post hatching (13.5 ± 0.7 mm) were stocked at density of 10 larvae L-1 in 5-L tanks each. The experimental treatments were: F2T (feeding 8h00 and 17h00); F2M (feeding 8h00 and 12h30); F3 (feeding 8h00, 12h30 and 17h00); and F4 (feeding 8h00, 11h00, 14h00 and 17h00). During this phase Artemia nauplii were used as food. In the second phase, during 15 days, juveniles were restocked in 20-L tanks at density of 2.2 juveniles L-1, and kept the same feeding frequencies of the first phase. Commercial dry diet containing 40% crude protein was used as food. No effect of feeding frequency on growth and survival, during both phases, was observed. However, survival decreases from the first to the second phase, showing the importance of the type of food. During the L. alexandri larviculture should be recommended twice a day feeding frequency.

RESUMO Devido aos efeitos da utilização indiscriminada de fungicidas, diversos estudos vêm sendo desenvolvidos na busca por formas alternativas de controle da podridão-parda, causada por Monilinia fructicola, em pós-colheita de pêssego. O objetivo deste estudo foi estimar o tamanho ótimo de amostra para avaliar a média do tamanho da lesão pêssegos e a influência de diferentes extratos vegetais nos frutos sobre o tamanho de amostra. Foi conduzido um experimento de três formas de preparo (FPE) e outro experimento de sete formas de aplicação (FAE) de extratos de canola e mostarda sobre pêssegos, com posterior aplicação do inóculo do patógeno. Foram usados cinco frutos em cinco repetições por tratamento. As avaliações foram feitas através da medição da área da lesão nos frutos. Foi determinado o tamanho de amostra necessário para a estimacão da média para cada tratamento e cada experimento. Para a mensuração do tamanho da lesão, 99 frutos em FPE e 23 frutos em FAE são suficientes para a estimação da média com um erro de estimação de 10% da média. Usando um mesmo erro de estimação, o tamanho de amostra (número de frutos) depende dos extratos (canola e mostarda), lotes de frutos e formas de extração e de aplicação dos extratos nos frutos. | ABSTRACT The identification of brown rot control derivatives has been the focus of intense research owing to the negative effects of the unrelenting usage of fungicides. Brown rot, caused by Monilinia fructicola, is an important post-harvest disease of peaches. The goal of this study was to estimate the optimum sample size of peaches in order to assess the average lesion size and the influence of different plant extracts on the fruits. Three preparation forms (FPE) were evaluated, as well as another seven forms of application (FAE) of canola and mustard extracts on peaches, with applications of the pathogen's inoculum. Five fruits were utilized in five repetitions per treatment. Evaluation involved measurement of the fruits' lesioned areas. The necessary sampling size was determined for estimation of the averages for each treatment and experiment. For measurement of the lesion size, 99 fruits in FPE and 23 fruits in FAE were sufficient for estimating the average with an estimation error of 10%. Based on the same estimation error, the sampling size is contingent on the extracts (canola, and mustard), batches of fruits, forms of extraction, and extract application on the fruits.

The identification of brown rot control derivatives has been the focus of intense research owing to the negative effects of the unrelenting usage of fungicides. Brown rot, caused by Monilinia fructicola, is an important post-harvest disease of peaches. The goal of this study was to estimate the optimum sample size of peaches in order to assess the average lesion size and the influence of different plant extracts on the fruits. Three preparation forms (FPE) were evaluated, as well as another seven forms of application (FAE) of canola and mustard extracts on peaches, with applications of the pathogen’s inoculum. Five fruits were utilized in five repetitions per treatment. Evaluation involved measurement of the fruits’ lesioned areas. The necessary sampling size was determined for estimation of the averages for each treatment and experiment. For measurement of the lesion size, 99 fruits in FPE and 23 fruits in FAE were sufficient for estimating the average with an estimation error of 10%. Based on the same estimation error, the sampling size is contingent on the extracts (canola, and mustard), batches of fruits, forms of extraction, and extract application on the fruits.

RESUMO Sete descritores bioquímicos foram utilizados para estimar a variabilidade genotípica de linhagens de amendoim submetidas a estresse hídrico moderado. Seis genótipos, sendo quatro linhagens e duas cultivares, foram cultivados em vasos, cada um contendo duas plantas e mantidas em casa de vegetação. Aos 15 dias após a emergência, procedeu-se a diferenciação dos tratamentos: Controle, as plantas mantidas com rega diariamente; Estresse, as plantas submetidas à suspensão total de rega durante 15 dias. O delineamento experimental foi inteiramente casualizado, com esquema fatorial 6 x 2 (genótipos x tratamentos hídricos), com cinco repetições. As variáveis bioquímicas avaliadas foram: catalase (CAT), ascorbato peroxidase (APX), guaiacol peroxidase (GPX), prolina livre, carboidratos totais, proteínas solúveis e aminoácidos. Baseado nos resultados das análises bioquímicas e de estimativa da variabilidade genotípica, a prolina demonstrou ser o descritor mais adequado para seleção de genótipos tolerantes ao estresse hídrico, contribuindo para indicar as linhagens L81V e L108V como mais promissoras, para um programa de melhoramento visando tolerância à seca. | ABSTRACT Seven biochemical descriptors were used to estimate the genotypic variability of peanut in response to moderate water stress. Six genotypes, constituted by four lines and two cultivars, were grown in pots, each containing two plants. At 15 days after emergence (DAE), the treatment differentiation was carried out: Control-plants maintained with daily watering, and Stress-plants submitted to water stress by complete suspension of watering for 15 days. The experimental design was completely randomized with factorial scheme 6 x 2 (genotype x water treatments), with five replications. The biochemical variables evaluated were: catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), free proline, total carbohydrates, soluble proteins, and amino acids. Results obtained by biochemical analysis and estimation of genotypic variability indicated that proline is the most appropriate descriptor for selecting genotypes tolerant to water stress, which led to identification of L81V and L108V as promising lines for drought tolerance breeding program.

Seven biochemical descriptors were used to estimate the genotypic variability of peanut in response to moderate water stress. Six genotypes, constituted by four lines and two cultivars, were grown in pots, each containing two plants. At 15 days after emergence (DAE), the treatment differentiation was carried out: Control-plants maintained with daily watering, and Stress-plants submitted to water stress by complete suspension of watering for 15 days. The experimental design was completely randomized with factorial scheme 6 x 2 (genotype x water treatments), with five replications. The biochemical variables evaluated were: catalase (CAT), ascorbate peroxidase (APX), guaiacol peroxidase (GPX), free proline, total carbohydrates, soluble proteins, and amino acids. Results obtained by biochemical analysis and estimation of genotypic variability indicated that proline is the most appropriate descriptor for selecting genotypes tolerant to water stress, which led to identification of L81V and L108V as promising lines for drought tolerance breeding program.

ABSTRACT Changes in soils management systems, including the application of green manure, are able to increase crop productivity. The aim of this study was to propose a soil management system with the use of green manure to improve the nutritional status and melon productivity in the submedian of the São Francisco Valley. The experiment was installed in Typic Plinthustalf and conducted in split plot. There were two soil tillage systems, tillage (T) and no tillage (NT), and three types of green manure (two vegetal cocktails: VC1 - 75% legumes (L) + 25% non-legumes (NL); VC2- 25% L+ 75% NL and spontaneous vegetation (SV)). The experimental design was a randomised block with four replications. Fourteen species of legumes, grasses and oilseeds were used for the composition of the plant cocktails. We evaluated production of the dry shoot and root biomass and carbon and nutrient accumulation by green manures and melon plant. Data were subjected to analysis of variance and the treatment means were compared by Tukey´s test (P<0.05). Shoot biomass production and carbon and nutrient accumulation were higher in plant mixtures compared to spontaneous vegetation. The root system of the plant cocktails added larger quantities of biomass and nutrients to the soil to a depth of 0.60 m when compared to the spontaneous vegetation. The cultivation of plant cocktails with soil tillage, regardless of their composition, is a viable alternative for adding biomass and nutrients to the soil in melon crops in semi-arid conditions, providing productivity increases. | RESUMO Mudanças nos sistemas de manejo de solos, incluindo adubação verde, podem aumentar a produtividade das culturas. O objetivo deste trabalho foi propor um sistema de manejo do solo com uso de adubação verde para melhorar o estado nutricional e a produtividade do melão no Vale do Submédio São Francisco. O experimento foi instalado em Argissolo Amarelo, em parcelas subdivididas, sendo as parcelas dois sistemas de preparo do solo, convencional (C) e plantio direto (PD), e as subparcelas três tipos de adubação verde (dois coquetéis vegetais: CV1- 75% leguminosas (L) + 25 % não-leguminosas (NL); CV2-25% L + 75% NL e vegetação espontânea (VE)). Após 70 dias da semeadura os adubos verdes foram manejados. Foram avaliados a produção de fitomassa aérea e radicular, acúmulo de nutrientes e C dos adubos verdes e a produtividade meloeiro. Os dados foram submetidos à análise de variância ao nível de 5% de probabilidade e as médias dos tratamentos foram comparados pelo teste de Tukey, ao nível de 5% de probabilidade. A produção de fitomassa da parte aérea e o acúmulo de carbono e nutrientes foram maiores nos coquetéis vegetais. O sistema radicular dos coquetéis vegetais adicionou maior quantidade de fitomassa e nutrientes no solo até 0,60 m, quando comparado com a vegetação espontânea. O cultivo de coquetéis vegetais, com incorporação da fitomassa, independentemente da sua composição, é uma alternativa viável para a adição de biomassa e nutrientes ao solo em condições semiáridas, proporcionando aumento de produtividade do meloeiro.

Changes in soils management systems, including the application of green manure, are able to increase crop productivity. The aim of this study was to propose a soil management system with the use of green manure to improve the nutritional status and melon productivity in the submedian of the São Francisco Valley. The experiment was installed in Typic Plinthustalf and conducted in split plot. There were two soil tillage systems, tillage (T) and no tillage (NT), and three types of green manure (two vegetal cocktails: VC1- 75% legumes (L) + 25% non-legumes (NL); VC2- 25% L+ 75% NL and spontaneous vegetation (SV)). The experimental design was a randomised block with four replications. Fourteen species of legumes, grasses and oilseeds were used for the composition of the plant cocktails. We evaluated production of the dry shoot and root biomass and carbon and nutrient accumulation by green manures and melon plant. Data were subjected to analysis of variance and the treatment means were compared by Tukey´s test (P<0.05). Shoot biomass production and carbon and nutrient accumulation were higher in plant mixtures compared to spontaneous vegetation. The root system of the plant cocktails added larger quantities of biomass and nutrients to the soil to a depth of 0.60 m when compared to the spontaneous vegetation. The cultivation of plant cocktails with soil tillage, regardless of their composition, is a viable alternative for adding biomass and nutrients to the soil in melon crops in semi-arid conditions, providing productivity increases.

ABSTRACT The objective of this study was to evaluate the symbiotic efficiency of three novel nitrogen-fixing bacterial strains with cowpea cv. BRS Guariba as forage. Two experiments were carried out in the field in Balsas and São Raimundo das Mangabeiras, MA, in a randomized block design with seven treatments and four replications: three novel strains efficient in symbiotic nitrogen fixation with cowpea (UFLA 3 -153, UFLA 3-154 and UFLA 3-164), two strains already approved as inoculants by MAPA (UFLA 3-84/SEMIA 6461 and INPA 3-11B/SEMIA 6462), and two controls without inoculation, with and without mineral N. Symbiotic efficiency of strains was determined by the number of nodules, nodules dry matter, shoot dry matter, relative efficiency, crude protein content and shoot N content. Strains UFLA 3-154 and UFLA 3-164 were the most efficient in Balsas, whereas UFLA 3-153 and UFLA 3-164 were the most efficient in São Raimundo das Mangabeiras. Strains UFLA 3-153, UFLA 3-154 and UFLA 3-164 were more efficient in symbiotic nitrogen fixation with cowpea than the strains already approved as inoculants UFLA 3-84 and INPA 3-11B in the climatic and edaphic conditions of southern Maranhão. UFLA 3-164 is the most efficient strain in this region. | RESUMO O objetivo deste trabalho foi avaliar a eficiência simbiótica de três novas estirpes de bactérias fixadoras de N2 em feijão-caupi cv. BRS Guariba como forrageira. Foram conduzidos dois experimentos em campo, em Balsas e São Raimundo das Mangabeiras, MA, em delineamento em blocos casualizados com sete tratamentos e quatro repetições, sendo: três novas estirpes eficientes em feijão-caupi (UFLA 3-153, UFLA 3-154 e UFLA 3-164), duas estirpes já aprovadas como inoculantes pelo MAPA (UFLA 3-84/SEMIA 6461 e INPA 3-11B/SEMIA 6462) e dois controles sem inoculação, com e sem N mineral. A eficiência simbiótica das estirpes foi determinada pelo número e massa seca de nódulos, produção de matéria seca da parte aérea, eficiência relativa, teor e acúmulo de proteína bruta e nitrogênio na parte aérea. As estirpes UFLA 03 -154 e UFLA 3-164 destacaram-se na eficiência simbiótica de N2 em Balsas e a UFLA 3-153 e UFLA 3-164 em São Raimundo das Mangabeiras. As estirpes UFLA 3-153, UFLA 3-154 e UFLA 3-164 são mais eficientes em fixar nitrogênio do que as estirpes aprovadas como inoculantes UFLA 3-84 e INPA 3-11B nas condições edafoclimáticas do sul do Maranhão. A UFLA 3-164 é a estirpe mais eficiente em fixar nitrogênio na região estudada.

The objective of this study was to evaluate the symbiotic efficiency of three novel nitrogen-fixing bacterial strains with cowpea cv. BRS Guariba as forage. Two experiments were carried out in the field in Balsas and São Raimundo das Mangabeiras, MA, in a randomized block design with seven treatments and four replications: three novel strains efficient in symbiotic nitrogen fixation with cowpea (UFLA 3-153, UFLA 3-154 and UFLA 3-164), two strains already approved as inoculants by MAPA (UFLA 3-84/SEMIA 6461 and INPA 3-11B/SEMIA 6462), and two controls without inoculation, with and without mineral N. Symbiotic efficiency of strains was determined by the number of nodules, nodules dry matter, shoot dry matter, relative efficiency, crude protein content and shoot N content. Strains UFLA 3-154 and UFLA 3-164 were the most efficient in Balsas, whereas UFLA 3-153 and UFLA 3-164 were the most efficient in São Raimundo das Mangabeiras. Strains UFLA 3-153, UFLA 3-154 and UFLA 3-164 were more efficient in symbiotic nitrogen fixation with cowpea than the strains already approved as inoculants UFLA 3-84 and INPA 3-11B in the climatic and edaphic conditions of southern Maranhão. UFLA 3-164 is the most efficient strain in this region.

RESUMO A ferrugem asiática da soja, cujo agente etiológico é o fungo Phakopsora pachyrhizi, causa redução da área foliar fotossintética e diminui a produtividade da cultura, sendo o controle químico uma das principais medidas no seu manejo. O objetivo do trabalho foi avaliar a eficácia e a seletividade do fungicida fluxapiroxade no controle da ferrugem asiática na cultura da soja, em condições edafoclimáticas do Cerrado. O experimento foi conduzido em área sob sistema de plantio direto, no Centro de Pesquisa Agrícola, Rio Verde, Goiás, durante a safra 2012/2013, utilizando a cultivar NA 7337. O delineamento experimental utilizado foi blocos ao acaso, com doze tratamentos e quatro repetições. Os tratamentos consistiram de aplicação de fluxapiroxade (FX), piraclostrobina (PT), epoxiconazol (EX) e metconazol (MZ). A severidade média da doença nas plantas chegou a 37% na testemunha. Todos os tratamentos contendo fungicidas diferiram da testemunha. Os tratamentos 9, 10, 11 e 12 foram os que proporcionaram maiores níveis de controle da ferrugem asiática, os tratamentos 10, 11 e 12 alcançaram maiores massa de mil grãos e os tratamentos 2, 3 e 11 foram mais produtivos que a testemunha, porém inferiores aos 4, 5, 6, 7, 8, 9, 10 e 12, sendo estes estatisticamente iguais. O incremento de produtividade em relação à testemunha variou de 10,05% (piraclostrobina, epoxiconazol + piraclostrobina + óleo mineral) a 30,55% (piraclostrobina, piraclostrobina + fluxapiroxade + óleo mineral, piraclostrobina + metconazol + óleo mineral). Os maiores níveis de controle foram evidenciados nos fungicidas contendo fluxapiroxade. | ABSTRACT The etiologic agent of the Asian soybean rust is the Phakopsora pachyrhizi, which causes a reduction in the photosynthetic leaf area and, consequently, in the crop yield. Chemical control is one of the main measures for its management. The objective of this work was to evaluate the efficacy and selectivity of the fluxapyroxad fungicide on controlling the Asian soybean rust, under the edaphoclimatic conditions of the Cerrado biome. The experiment was conducted in an area under no-tillage system, in the Agricultural Research Center, Rio Verde, Goias, Brazil, during the 2012/2013 crop season, using the cultivar NA7337. A randomized block experimental design was used, with twelve treatments and four replications. The treatments consisted of applications of fluxapyroxad (FX), pyraclostrobin (PT), epoxiconazole (EX) and metconazole (MZ). The average severity of the disease in the plants reached 37% in the Control. All treatments with fungicides differed from the Control. Treatments 9, 10, 11 and 12 provided the greatest rates of soybean rust control. The treatments 10, 11 and 12 had the highest thousand grain weights, and the yields of the treatments 2, 3 and 11, despite higher than the Control, were lower than the treatments 4, 5, 6, 7, 8, 9, 10 and 12, which had statistically equal yields. The increasing in yield, compared to the Control, ranged from 10.05% (pyraclostrobin, epoxiconazole + pyraclostrobin + mineral oil) to 30.55% (pyraclostrobin, pyraclostrobin + fluxapyroxad + mineral oil and pyraclostrobin + metconazole + mineral oil). The highest rates of soybean rust control were presented by fungicides containing fluxapyroxad.

The etiologic agent of the Asian soybean rust is the Phakopsora pachyrhizi, which causes a reduction in the photosynthetic leaf area and, consequently, in the crop yield. Chemical control is one of the main measures for its management. The objective of this work was to evaluate the efficacy and selectivity of the fluxapyroxad fungicide on controlling the Asian soybean rust, under the edaphoclimatic conditions of the Cerrado biome. The experiment was conducted in an area under no-tillage system, in the Agricultural Research Center, Rio Verde, Goias, Brazil, during the 2012/2013 crop season, using the cultivar NA7337. A randomized block experimental design was used, with twelve treatments and four replications. The treatments consisted of applications of fluxapyroxad (FX), pyraclostrobin (PT), epoxiconazole (EX) and metconazole (MZ). The average severity of the disease in the plants reached 37% in the Control. All treatments with fungicides differed from the Control. Treatments 9, 10, 11 and 12 provided the greatest rates of soybean rust control. The treatments 10, 11 and 12 had the highest thousand grain weights, and the yields of the treatments 2, 3 and 11, despite higher than the Control, were lower than the treatments 4, 5, 6, 7, 8, 9, 10 and 12, which had statistically equal yields. The increasing in yield, compared to the Control, ranged from 10.05% (pyraclostrobin, epoxiconazole + pyraclostrobin + mineral oil) to 30.55% (pyraclostrobin, pyraclostrobin + fluxapyroxad + mineral oil and pyraclostrobin + metconazole + mineral oil). The highest rates of soybean rust control were presented by fungicides containing fluxapyroxad.

ABSTRACT The potential insecticidal of oils from southwestern Amazon plants against Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) was investigated. Initial bioassays were performed with undiluted oils from 11 plant species. The efficacy of the oils was evaluated against eggs and third -instar caterpillars of S. frugiperda. The oils of Copaifera sp. (Leguminosae), Orbignya phalerata (Arecaceae), and Carapa guianensis (Meliaceae) displayed a high efficacy against the caterpillars and were used in subsequent concentration-response bioassays, at concentrations established through preliminary tests. The highest nonlethal concentrations of oils and the lowest lethal concentrations were calculated. A completely randomized design was adopted in both bioassays. The LC50 of the oils varied from 7.50 to 60.84% (v/v). Copaifera sp. oil had the highest toxicity and was 6.84-fold more toxic than O. phalerata oil and 8.11-fold more toxic than Carapa guianensis oil. In general, oils from Copaifera sp., O. phalerata, and Carapa guianensis were effective in controlling S. frugiperda caterpillars under laboratory conditions, and are good candidates for use in integrated management programs of corn pests. | RESUMO Investigou-se o potencial inseticida de óleos vegetais de plantas ocorrentes na Amazônia Sul Ocidental sobre Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae). Inicialmente, foram realizados bioensaios utilizando-se óleos puros (sem diluições), oriundos de 11 espécies vegetais. A eficiência dos óleos foi avaliada para ovos e para lagartas de terceiro ínstar de S. frugiperda. Os óleos de Copaifera sp. (Leguminosae), Orbignya phalerata (Arecaceae) e Carapa guianensis (Meliaceae) apresentaram elevada eficiência para as lagartas de S. frugiperda, sendo, portanto utilizados nos bioensaios subsequentes de concentração-resposta. As concentrações de cada óleo, utilizadas nestes testes de concentração-mortalidade, foram estabelecidas por meio de testes preliminares. Estabeleceram-se as maiores concentrações dos óleos em que não ocorresse morte de insetos e as menores concentrações em que ocorresse a maior mortalidade. Com base nos dados obtidos, foram estabelecidos os intervalos definitivos. O delineamento inteiramente casualizado foi adotado em ambos os bioensaios. As CL50 variaram de 7,50 a 60,84% (v/v) entre os óleos. O óleo de Copaifera sp. apresentou maior toxicidade para as lagartas, sendo 6,84 vezes mais tóxico que o óleo de O. phalerata e 8,11 vezes mais tóxico que o óleo de Carapa guianensis. Em geral, os óleos de Copaifera sp., O. phalerata e Carapa guianensis são eficazes no controle de lagartas de S. frugiperda, sob condições de laboratório, destacando-se como candidatos a uso nos programas de manejo integrado das pragas do milho.

The potential insecticidal of oils from southwestern Amazon plants against Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) was investigated. Initial bioassays were performed with undiluted oils from 11 plant species. The efficacy of the oils was evaluated against eggs and third-instar caterpillars of S. frugiperda. The oils of Copaifera sp. (Leguminosae), Orbignya phalerata (Arecaceae), and Carapa guianensis (Meliaceae) displayed a high efficacy against the caterpillars and were used in subsequent concentration-response bioassays, at concentrations established through preliminary tests. The highest nonlethal concentrations of oils and the lowest lethal concentrations were calculated. A completely randomized design was adopted in both bioassays. The LC50 of the oils varied from 7.50 to 60.84% (v/v). Copaifera sp. oil had the highest toxicity and was 6.84-fold more toxic than O. phalerata oil and 8.11-fold more toxic than Carapa guianensis oil. In general, oils from Copaifera sp., O. phalerata, and Carapa guianensis were effective in controlling S. frugiperda caterpillars under laboratory conditions, and are good candidates for use in integrated management programs of corn pests.

RESUMO A cafeicultura brasileira está presente em áreas planas e declivosas. Nas regiões planas a mecanização nas operações cafeeiras é intensa, do contrário, são as regiões declivosas, que não mecanizam algumas das operações, dentre elas a colheita. Para suplantar esta dificuldade a indústria vem desenvolvendo colhedoras capazes de colher em declividades de até 30%. O desempenho operacional e a eficiência de colheita são influenciadas pela declividade. Diante disto objetivou-se no presente trabalho avaliar o desempenho operacional e a eficiência de colheita de uma colhedora confeccionada para colher em elevadas declividades, testando suas principais regulagens. O experimento foi conduzido no município de Santo Antônio do Amparo, região do Sul de Minas Gerais, em cinco talhões com declividade de 10, 15, 20, 25 e 30%, utilizando uma colhedora Electron automotriz (TDI), testando três vibrações das hastes (600, 800 e 1.000 rpm) e duas velocidades (800 e 1.000 m h-1). Obteve-se que em na declividade de 10%, deve-se utilizar velocidades reduzidas (800 m h-1) para minimizar a quantidade de café caído. Em declividades acima de 20% a colheita mecanizada demanda 21,6% a mais de tempo para ser procedida que em declividades menores. O tempo de parada na operação da colheita mecanizada corresponde a 10,66 a 29,18% do tempo total de colheita, em função do maior número de manobras. | ABSTRACT Brazilian coffee farming is carried out both on flat and steep lands. In flat areas, mechanized operations are intensive; however, in steep slope areas, certain mechanized operations cannot be performed, such as harvesting. Based on this, the industry has developed machinery to harvest coffee in areas with up to 30% slope. However, harvesters have their efficiency and operational performance influenced by land slope. Thus, this study aimed to evaluate the operational performance and harvesting efficiency of a steep -slope harvester under different situations, using different speed settings. The experiment was carried out in the county of Santo Antônio do Amparo, state of Minas Gerais, Brazil, using five coffee stands with 10, 15, 20, 25 and 30% slope. Evaluations were performed with a self-propelled harvester (Electron, TDI(r), Araguari, MG, Brazil) at three rotation speeds (600, 800 and 1.000 rpm) and two ground speeds (800 and 1.000 m h -1). The results showed the lower speed (800 m h-1) was suitable for 10% slope areas since the amount of fallen coffee berries. For areas of 20% slope, harvesting time was 21.6% longer than in flatter areas. Downtime varied from 10.66 to 29.18% total harvest due to a higher number of maneuvers.

Brazilian coffee farming is carried out both on flat and steep lands. In flat areas, mechanized operations are intensive; however, in steep slope areas, certain mechanized operations cannot be performed, such as harvesting. Based on this, the industry has developed machinery to harvest coffee in areas with up to 30% slope. However, harvesters have their efficiency and operational performance influenced by land slope. Thus, this study aimed to evaluate the operational performance and harvesting efficiency of a steep-slope harvester under different situations, using different speed settings. The experiment was carried out in the county of Santo Antônio do Amparo, state of Minas Gerais, Brazil, using five coffee stands with 10, 15, 20, 25 and 30% slope. Evaluations were performed with a self-propelled harvester (Electron, TDI®, Araguari, MG, Brazil) at three rotation speeds (600, 800 and 1.000 rpm) and two ground speeds (800 and 1.000 m h-1). The results showed the lower speed (800 m h-1) was suitable for 10% slope areas since the amount of fallen coffee berries. For areas of 20% slope, harvesting time was 21.6% longer than in flatter areas. Downtime varied from 10.66 to 29.18% total harvest due to a higher number of maneuvers.