Enzymatic stoichiometry in tropical soil under pure and mixed plantations of eucalyptus with N2-fixing trees

Soil enzymes play a fundamental role in nutrient cycling in forest systems. The stoichiometry of C, N, and P­acquiring enzymes has been used to indicate nutrient limitation in the soil. However, the enzymatic stoichiometry remains poorly understood in pure and mixed eucalypt plantations. Thus, this study aims to assess the activity of enzymes in the soil to address the hypothesis that the introduction of N2-fixing trees could influence the enzymatic stoichiometry on C, N, and P cycling. The activity of ß-glucosidase (BG), urease (U), and acid phosphatase (AP) was assessed in soil (0-20 cm depth) of pure Eucalyptus grandis without (E) and with N fertilization (E+N), and a mixed system with E. grandis and Acacia mangium (E+A), and a pure A. mangium (A) plantation at 27 and 39 months after planting. The activities of BG/U, BG/AP, and U/AP were used to calculate the enzyme C/N, C/P, and N/P ratios, respectively. Rates of N­acquiring enzymes were higher in E and E+N, while soil microorganisms invested in P­acquiring enzymes in A and E+A. The vector length and angle demonstrated that C demand by microorganisms does not change in relation to N and P, regardless of the treatment. However, N demand decreased in relation to P in A and E+A (mainly at 27 months). Our results suggest that enzymes activity in pure eucalypt systems is limited for their soil-litter nutrient contents. At the same time while acacia and mixed plantation seem to invest in P­acquiring enzymes to improve biological N2 fixation promoted by diazotrophic bacteria associated to acacia.

The use of rhizobium and mycorrhizae in soil containing rhizobiophage to improve growth and nodulation of cowpea

The interaction between leguminous plants and rhizosphere microorganisms is essential because it can either enhance or inhibit the beneficial effects of individual species. Phages are one of the biotic factors with a negative impact on the beneficial bacteria in soil rhizosphere. In the current study, phage showed lytic activity against Bradyrhizobium sp. Vigna (tal16) with an icosahedral head at a 43.44 nm diameter and a long non-contractile tail, measuring 99.85 nm. This phage belongs to the Siphoviridae family, found in the Met El-Ez area of Dakalia Governorate in Egypt. The results revealed that the presence of phage in soil affected nodulation and growth parameters. Mycorrhizal inoculation aggravated the negative effects of this phage. Cowpea grown in soil containing phage VB_BrV_SD4 showed a reduction in the nodule number, nitrogenase activity, and total N of 40-50 %; however, mycorrhizal inoculation augmented this negative effect with a reduction percentage to 20-28 %. Mycorrhizal inoculation also improved total chlorophyll, carotenoids, legume amount, and the seed protein content.

Trichoderma asperellumand rhizobacteria improving biomass accumulation and gas exchange of lowland rice / Thichoderma asperellum e rizobactérias melhorando o acúmulo de biomassa e trocas gasosas em arroz irrigado

Rice the main source of energy to maintain the metabolism for almost four billion people worldwide. Riceplants treated with multifunctional microorganisms may be a good way for sustainable improvement of crop grain yield. Aimed study the effect of types and ways of microorganisms application in tropical lowland rice production, evaluated by biomass production and gas exchange. The greenhouse trial was in a completely randomized design, in factorial scheme 7 x 3 + 1, with four replication. Treatments were the combination of seven microorganisms: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) and Trichoderma asperellum pool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), with three forms of application (1. microbiolized seed; 2. microbiolized seed + soil drenched with microorganism at eight and 15 days after sowing (DAS)and 3. microbiolized seed + microorganism spray plant at eight and 15 DAS). Microbiolized seed was the best form of application, which allowed highest instantaneous carboxylation efficiency and yield of biomassproduction in lowland rice. Rhizobcteria BRM32114, followed by BRM32111, BRM32112 and fungi T. asperellum improved, an average, 17% in instantaneous carboxylation efficiency and 20% in dry shoot biomass production of lowland rice compared to the control plants.

Arroz é a principal fonte de energia para manutenção do metabolismo de quase quarto bilhões de pessoas no mundo todo. Plantas de arroz tratadas com microrganismos multifuncionais pode ser uma boa maneira para melhoria sustentável do rendimento de grãos. Objetivou-se estudar o efeito de tipos e formas de aplicação de microrganismos na produção de arroz irrigado tropical, avaliado pela produção de biomassa e trocas gasosas. Ensaio em casa de vegetação foi realizado em delineamento inteiramente casualizado, no esquema fatorial 7 x 3 + 1, com quatro repetições. Tratamentos consistiram da combinação de sete microrganismos: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) e Trichoderma asperellumpool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), com três formas de aplicação (1. semente microbiolizada; 2. semente microbiolizada + solo inundado com os microrganismos aos oito e 15 dias após a semeadura (DAS); e 3. semente microbiolizada + pulverização dos microrganismos nas plantas aos oito e 15 DAS). Microbiolização de sementes foi a melhor forma de aplicação dos microrganismos, o qual promoveu a maior taxa de eficiência instantânea de carboxilação e rendimento da produção de biomassa em arroz irrigado. Rizobactéria BRM32114, seguido por BRM32111, BRM32112 e fungo T. asperellum aumentaram, em média, 17% na eficiência instantânea de carboxilação e, 20% na produção de biomassa seca da parte aérea de arroz irrigado comparado com plantas controle.

Trichoderma asperellumand rhizobacteria improving biomass accumulation and gas exchange of lowland rice / Thichoderma asperellum e rizobactérias melhorando o acúmulo de biomassa e trocas gasosas em arroz irrigado

Rice the main source of energy to maintain the metabolism for almost four billion people worldwide. Riceplants treated with multifunctional microorganisms may be a good way for sustainable improvement of crop grain yield. Aimed study the effect of types and ways of microorganisms application in tropical lowland rice production, evaluated by biomass production and gas exchange. The greenhouse trial was in a completely randomized design, in factorial scheme 7 x 3 + 1, with four replication. Treatments were the combination of seven microorganisms: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) and Trichoderma asperellum pool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), with three forms of application (1. microbiolized seed; 2. microbiolized seed + soil drenched with microorganism at eight and 15 days after sowing (DAS)and 3. microbiolized seed + microorganism spray plant at eight and 15 DAS). Microbiolized seed was the best form of application, which allowed highest instantaneous carboxylation efficiency and yield of biomassproduction in lowland rice. Rhizobcteria BRM32114, followed by BRM32111, BRM32112 and fungi T. asperellum improved, an average, 17% in instantaneous carboxylation efficiency and 20% in dry shoot biomass production of lowland rice compared to the control plants.(AU)

Arroz é a principal fonte de energia para manutenção do metabolismo de quase quarto bilhões de pessoas no mundo todo. Plantas de arroz tratadas com microrganismos multifuncionais pode ser uma boa maneira para melhoria sustentável do rendimento de grãos. Objetivou-se estudar o efeito de tipos e formas de aplicação de microrganismos na produção de arroz irrigado tropical, avaliado pela produção de biomassa e trocas gasosas. Ensaio em casa de vegetação foi realizado em delineamento inteiramente casualizado, no esquema fatorial 7 x 3 + 1, com quatro repetições. Tratamentos consistiram da combinação de sete microrganismos: Bacillussp. (BRM32109 e BRM32110); Pseudomonas fluorescens(BRM32111); Pseudomonassp. (BRM32112); Burkholderia pyrrocinia(BRM32113); Serratiasp. (BRM32114) e Trichoderma asperellumpool (UFRA.T06 + UFRA.T09 + UFRA.T12 + UFRA.T52), com três formas de aplicação (1. semente microbiolizada; 2. semente microbiolizada + solo inundado com os microrganismos aos oito e 15 dias após a semeadura (DAS); e 3. semente microbiolizada + pulverização dos microrganismos nas plantas aos oito e 15 DAS). Microbiolização de sementes foi a melhor forma de aplicação dos microrganismos, o qual promoveu a maior taxa de eficiência instantânea de carboxilação e rendimento da produção de biomassa em arroz irrigado. Rizobactéria BRM32114, seguido por BRM32111, BRM32112 e fungo T. asperellum aumentaram, em média, 17% na eficiência instantânea de carboxilação e, 20% na produção de biomassa seca da parte aérea de arroz irrigado comparado com plantas controle.(AU)

Atividade enzimática do solo em pastagens de Urochloa manejados sob ofertas de forragem / Soil enzymatic activity of Urochloa pastures managed under different forage allowances

A atividade enzimática do solo reflete a atividade dos microrganismos que decompõem a matéria orgânica e liberam nutrientes às plantas. O objetivo foi avaliar a atividade enzimática no solo em pastagens de cultivares de Urochloa manejados sob as ofertas de forragem de 4, 7, 10 e 13 kg de matéria seca (MS)/100 kg de peso corporal (PC). O método de pastejo adotado foi mob-stocking, com quatro ciclos de pastejo (entre dezembro de 2008 e fevereiro de 2009). Também foi realizada uma amostragem em junho de 2009 para melhor caracterização, pois a mineralização da matéria orgânica no solo ocorre em longo prazo. Assim, as datas de coleta de solo para análise foram descritas como dias de avaliações e não como pastejos: 1 (de 17 a 20 de dezembro de 2008), 21 (de 07 a 10 de janeiro de 2009), 42 (de 28 a 31 de janeiro de 2009), 63 (de 18 a 21 de fevereiro de 2009), 183 (de 18 a 20 de junho de 2009). Foi avaliada a atividade enzimática no solo da desidrogenase, protease, arilsulfatase e celulase. O delineamento experimental foi inteiramente casualizado, com três repetições por oferta. Foi realizada a análise de variância e teste de Tukey ao nível de 5% de probabilidade, para comparação de médias, utilizando-se o procedimento o programa estatístico R. As análises foram realizadas de maneira individual para cada cultivar. De modo geral, nas pastagens das três cultivares estudadas, a atividade da desidrogenase foi maior (P<0,05) aos 63 dias e da protease no último dia de avaliação. O decorrer do período experimental implicou em mudanças na atividade da arilsulfatase e da celulase em relação às ofertas de forragem, mas sem um padrão de comportamento definido. As ofertas de forragem mostraram efeito sobre a atividade das enzimas ao longo do período de avaliação, porém sem padrão de comportamento definido, sendo observadas oscilações cíclicas da atividade dessas enzimas. As ofertas de forragem estudadas afetaram a atividade enzimática da desidrogenase, protease, arilsulfatase e...

Soil enzymatic activity reflects the activity microorganisms that decompose the organic matter and release nutrients into the soil that can be used by plants. The objective of this study was to evaluate soil enzymatic activity in Urochloa cultivar pastures managed under forage allowances of 4, 7, 10 and 13 kg dry matter/100 kg body weight. The grazing method adopted was mob-stocking, with four grazing cycles (between December 2008 and February 2009). Soil sampling was performed in June 2009 for better characterization since the mineralization of soil organic matter is a long-term process. Thus, the dates of soil sampling for analysis are reported as evaluation days and not as grazing: 1 (December 17 to 20, 2008), 21 (January 7 to 10, 2009), 42 (January 28 to 31, 2009), 63 (February 18 to 21, 2009), 183 (June 18 to 20, 2009). The soil enzymatic activity of dehydrogenase, protease, arylsulfatase, and cellulase was evaluated. The experimental design was completely randomized, with three replications per forage allowance. Analysis of variance and Tukey’s test at the 5% probability level were applied to compare means using the R statistical program. The analyses were performed individually for each cultivar. Overall, in pastures of the three cultivars studied, dehydrogenase activity was higher (P<0.05) on day 63 and protease on the last day of evaluation. The experimental period implied changes in the activity of arylsulfatase and cellulase according to forage allowance, but without a defined pattern. Forage allowances exerted an effect on the activity of the enzymes throughout the evaluation period, but there was no defined pattern. Cyclic oscillations in the activity of these enzymes were observed. The forage allowances studied affected the soil enzymatic activity of dehydrogenase, protease, arylsulfatase and cellulase in Urochloa pastures of the Marandu, Xaraes and Mulato varieties, but no pattern was found in...

Atividade enzimática do solo em pastagens de Urochloa manejados sob ofertas de forragem / Soil enzymatic activity of Urochloa pastures managed under different forage allowances

A atividade enzimática do solo reflete a atividade dos microrganismos que decompõem a matéria orgânica e liberam nutrientes às plantas. O objetivo foi avaliar a atividade enzimática no solo em pastagens de cultivares de Urochloa manejados sob as ofertas de forragem de 4, 7, 10 e 13 kg de matéria seca (MS)/100 kg de peso corporal (PC). O método de pastejo adotado foi mob-stocking, com quatro ciclos de pastejo (entre dezembro de 2008 e fevereiro de 2009). Também foi realizada uma amostragem em junho de 2009 para melhor caracterização, pois a mineralização da matéria orgânica no solo ocorre em longo prazo. Assim, as datas de coleta de solo para análise foram descritas como dias de avaliações e não como pastejos: 1 (de 17 a 20 de dezembro de 2008), 21 (de 07 a 10 de janeiro de 2009), 42 (de 28 a 31 de janeiro de 2009), 63 (de 18 a 21 de fevereiro de 2009), 183 (de 18 a 20 de junho de 2009). Foi avaliada a atividade enzimática no solo da desidrogenase, protease, arilsulfatase e celulase. O delineamento experimental foi inteiramente casualizado, com três repetições por oferta. Foi realizada a análise de variância e teste de Tukey ao nível de 5% de probabilidade, para comparação de médias, utilizando-se o procedimento o programa estatístico R. As análises foram realizadas de maneira individual para cada cultivar. De modo geral, nas pastagens das três cultivares estudadas, a atividade da desidrogenase foi maior (P<0,05) aos 63 dias e da protease no último dia de avaliação. O decorrer do período experimental implicou em mudanças na atividade da arilsulfatase e da celulase em relação às ofertas de forragem, mas sem um padrão de comportamento definido. As ofertas de forragem mostraram efeito sobre a atividade das enzimas ao longo do período de avaliação, porém sem padrão de comportamento definido, sendo observadas oscilações cíclicas da atividade dessas enzimas. As ofertas de forragem estudadas afetaram a atividade enzimática da desidrogenase, protease, arilsulfatase e...(AU)

Soil enzymatic activity reflects the activity microorganisms that decompose the organic matter and release nutrients into the soil that can be used by plants. The objective of this study was to evaluate soil enzymatic activity in Urochloa cultivar pastures managed under forage allowances of 4, 7, 10 and 13 kg dry matter/100 kg body weight. The grazing method adopted was mob-stocking, with four grazing cycles (between December 2008 and February 2009). Soil sampling was performed in June 2009 for better characterization since the mineralization of soil organic matter is a long-term process. Thus, the dates of soil sampling for analysis are reported as evaluation days and not as grazing: 1 (December 17 to 20, 2008), 21 (January 7 to 10, 2009), 42 (January 28 to 31, 2009), 63 (February 18 to 21, 2009), 183 (June 18 to 20, 2009). The soil enzymatic activity of dehydrogenase, protease, arylsulfatase, and cellulase was evaluated. The experimental design was completely randomized, with three replications per forage allowance. Analysis of variance and Tukeys test at the 5% probability level were applied to compare means using the R statistical program. The analyses were performed individually for each cultivar. Overall, in pastures of the three cultivars studied, dehydrogenase activity was higher (P<0.05) on day 63 and protease on the last day of evaluation. The experimental period implied changes in the activity of arylsulfatase and cellulase according to forage allowance, but without a defined pattern. Forage allowances exerted an effect on the activity of the enzymes throughout the evaluation period, but there was no defined pattern. Cyclic oscillations in the activity of these enzymes were observed. The forage allowances studied affected the soil enzymatic activity of dehydrogenase, protease, arylsulfatase and cellulase in Urochloa pastures of the Marandu, Xaraes and Mulato varieties, but no pattern was found in...(AU)

First report of the production of a potent biosurfactant with ,-trehalose by Fusarium fujikuroi under optimized conditions of submerged fermentation

Abstract Biosurfactants have many advantages over synthetic surfactants but have higher production costs. Identifying microorganisms with high production capacities for these molecules and optimizing their growth conditions can reduce cost. The present work aimed to isolate and identify a fungus with high biosurfactant production capacity, optimize its growth conditions in a low cost culture medium, and characterize the chemical structure of the biosurfactant molecule. The fungal strain UFSM-BAS-01 was isolated from soil contaminated with hydrocarbons and identified as Fusarium fujikuroi. To optimize biosurfactant production, a PlackettBurman design and a central composite rotational design were used. The variables evaluated were pH, incubation period, temperature, agitation and amount of inoculum in a liquid medium containing glucose. The partial structure of the biosurfactant molecule was identified by nuclear magnetic resonance spectrometry. F. fujikuroi reduced surface tension from 72 to 20 mN m1 under the optimized conditions of pH 5.0, 37 °C and 7 days of incubation with 190 rpm agitation. The partial identification of the structure of the biosurfactant demonstrated the presence of an ,-trehalose. The present study is the first report of the biosynthesis of this compound by F. fujikuroi, suggesting that the biosurfactant produced belongs to the class of trehalolipids.

First report of the production of a potent biosurfactant with alfa, beta-trehalose by Fusarium fujikuroi under optimized conditions of submerged fermentation

Biosurfactants have many advantages over synthetic surfactants but have higher production costs. Identifying microorganisms with high production capacities for these molecules and optimizing their growth conditions can reduce cost. The present work aimed to isolate and identify a fungus with high biosurfactant production capacity, optimize its growth conditions in a low cost culture medium, and characterize the chemical structure of the biosurfactant molecule. The fungal strain UFSM-BAS-01 was isolated from soil contaminated with hydrocarbons and identified as Fusarium fujikuroi. To optimize biosurfactant production, a Plackett–Burman design and a central composite rotational design were used. The variables evaluated were pH, incubation period, temperature, agitation and amount of inoculum in a liquid medium containing glucose. The partial structure of the biosurfactant molecule was identified by nuclear magnetic resonance spectrometry. F. fujikuroi reduced surface tension from 72 to 20 mN m−1 under the optimized conditions of pH 5.0, 37 °C and 7 days of incubation with 190 rpm agitation. The partial identification of the structure of the biosurfactant demonstrated the presence of an α,β-trehalose. The present study is the first report of the biosynthesis of this compound by F. fujikuroi, suggesting that the biosurfactant produced belongs to the class of trehalolipids.(AU)

Viabilidade de enterobactérias em unidades de armazenamento de dejetos líquidos de suínos.

A produção animal, em especial a suinocultura, possui papel fundamental no desenvolvimento agropecuário do Brasil. A forma mais usual de armazenamento dos dejetos, na maioria das granjas suinícolas da região sul do Brasil, são as esterqueiras ou lagoas de decantação. Microrganismos como Salmonella sp. e Escherichia coli, podem ser determinantes para desencadearem impactos na saúde única, deste modo, a resistência aos antimicrobianos é um grande desafio. O objetivo desse estudo foi avaliar a eficiência do processo de estabilização do dejeto líquido de suínos em unidades de armazenamento (lagoas de estabilização) quanto à presença de bactérias patogênicas e resistência a antibióticos em propriedades com suinocultura, localizadas no município de Presidente Castello Branco, Santa Catarina (SC), Brasil. O trabalho foi realizado em dois ensaios: na condição preconizada de manejo (ensaio 1) foi investigada a eficiência na redução de Salmonella sp. e E. coli em condições ideais de manejo e resistência dos isolados a antimicrobianos. Para tanto foram realizadas amostragens nas esterqueiras em três profundidades (0 -10, 10 20 e 20 30 cm) em dois intervalos de tempo, T0 e T60. Foram realizadas as análises de pesquisa qualitativa e quantitativa de Salmonella sp, assim como, a investigação de enterobactérias não E. coli (ENEC) e E. coli (EC). Para verificação dos perfis de resistência aos antibióticos, foram realizados antibiogramas por meio da técnica de disco-difusão. Para as condições reais de manejo (ensaio 2), foram utilizadas 9 unidades amostrais, coletadas no momento da distribuição e realizada pesquisa de enterobactérias. No ensaio 1 a redução das populações bacterianas quando avaliadas em relação ao intervalo de coletas (T0 e T60) para P <0,0001, apresentaram as seguintes correlações: ENEC = 0,54 e EC = 0,78. Isso demonstra que o indicador EC foi o mais confiável em termos de avaliação de eficiência de remoção de bactérias indicadoras no processo de estabilização do dejeto suíno. Não houve efeito da variação de profundidade sobre a quantificação de ENEC (P=0,8871) e EC (P=0,9817), nos intervalos estudados. Os antibiogramas demonstraram multirresistência bacteriana. Em condições reais de manejo (ensaio 2) foi observada forte correlação negativa entre CT e TRH (r = -0,87) e entre EC e TRH (r = -0,86), indicando que o tempo de retenção é fundamental para estabilização do dejeto, reduzindo o risco de contaminação ambiental por bactérias patogênicas quando da deposição em solo. A concentração média de coliformes fecais (EC) observada no experimento 1 foi de 1,29 x 102 UFC 100 mL-1 enquanto no ensaio 2 o valor médio foi de 4,1 x105 UFC 100 mL-1 refletindo a variação entre condições ideais e operacionais de campo em relação ao tempo de estabilização. O manejo do dejeto suíno quando realizado em desacordo com as normas sanitárias vigentes pode implicar em riscos de propagação de microrganismos patogênicos, da mesma forma que a resistência das bactérias aos antibióticos gera prejuízos à homeostase da saúde única.

Animal production, especially swine, has a fundamental role in agricultural development in Brazil. The most common form of waste storage in most swine farms in southern Brazil is in manure pits or decantation ponds. Microorganisms like Salmonella sp. and Escherichia coli, can be determinant to trigger impacts on one health, thus, antimicrobial resistance is a great challenge. The aim of this study was to evaluate the efficiency of the swine manure stabilization process in storage units (stabilization ponds) for the presence of pathogenic bacteria and antibiotic resistance in pig farms located in the municipality of Presidente Castello Branco, Santa Catarina (SC), Brazil. The established criterion was the presence of bacteria indicative of pathogens and antibiotic resistance. The study was carried out in two trials: in the recommended management condition (trial 1), the efficiency in reducing Salmonella sp. and E. coli under ideal management conditions and resistance of antimicrobials isolates. For this purpose, samplings were carried out in manure pits at three depths (0 -10, 10 20 and 20 30 cm) at two time intervals, T0 and T60. Were realized the analysis of qualitative research of Salmonella sp and quantitative research of Salmonella sp., also investigation of enterobacteria non-E.coli (ENEC) and E.coli (EC). To verify the antibiotic resistance profiles. For the real management conditions (trial 2), 9 sampling units were used, collected at the time of distribution and research for enterobacteria was carried out. In trial 1, the reduction of bacterial populations when evaluated in relation to the sampling interval (T0 and T60) for P < 0.0001, presented the correlations: ENEC = 0.54 and EC = 0.78. This demonstrates that the EC indicator was the most reliable in terms of evaluating the efficiency of removal of indicator bacteria in the stabilization process of swine manure. There was no effect of depth variation on the quantification of ENEC (P=0.8871) and EC (P=0.9817) in the studied intervals. The antibiograms demonstrated bacterial multiresistance. In the real management conditions (trial 2) a strong negative correlation was observed between CT and TRH (r = -0.87) and between EC and TRH (r = -0.86), indicating that retention time is essential for stabilization of the manure, reducing the risk of environmental contamination by pathogenic bacteria when deposited in soil. The mean concentration of fecal coliforms (EC) observed in experiment 1 was 1.29 x 102 UFC 100 mL-1 while in experiment 2 the mean value was 4.1 x105 UFC 100 mL-1 reflecting the variation between recommended management and real management in relation to the stabilization time. The management of swine manure, when working in disagreement with the current sanitary norms, may imply in risks of propagation of pathogenic microorganisms, in the same way that the resistance of bacteria to antibiotics harms the homeostasis of one health.

PESQUISA DE Escherichia coli DIARREIOGÊNICA EM ÁGUA DE MÚLTIPLOS USOS COMO MODELO DE VIGILÂNCIA EM SAÚDE ÚNICA

A Bacia Hidrográfica do Rio Mearim se destaca por sua importância social, econômica, ambiental, energética e cultural, sobretudo, para pequenos produtores rurais que utilizam essa fonte de água em atividades agroprodutivas e para pescadores artesanais que retiram desse recurso hídrico seu alimento e sustento. Nesse sentido, objetivou-se pesquisar Escherichia coli diarreiogênica em água de múltiplos usos como modelo de vigilância em saúde única. Para a realização do estudo coletou-se amostras de água em cinco pontos previamente selecionados para os municípios de Arari e Vitória do Mearim, estado do Maranhão, o que correspondeu a uma área do baixo curso do rio Mearim. De cada ponto foram coletadas amostras em triplicata, totalizando 30 amostras, sendo 15 amostras por município. As amostras foram coletadas em frascos estéreis de vidro borosilicato, com capacidade de 500 mL, de maneira asséptica e acondicionadas ao abrigo de luz solar em caixas isotérmicas com gelo reciclável. Para a quantificação de coliformes totais e E. coli utilizou-se o sistema cromogênico enzimático (Colilert, Idexx, USA) e das amostras positivas nesse teste procedeu-se ao isolamento e confirmação da bactéria em estudo por meio de metodologia convencional (enriquecimento das amostras e identificação bioquímica das colônias isoladas). A extração do DNA das culturas puras de E. coli foi realizada por aquecimento seguido da caracterização por meio da reação em cadeia da polimerase (PCR) utilizando o Kit GoTaq® Colorless Master Mix (Promega®) de acordo com as recomendações do fabricante. Das amostras analisadas, 100% (n=30) apresentaram coliformes totais com populações bacterianas que variaram de 7.701 a 24.196 NMP/100 mL para o município de Arari e 3.524 a 24.196 NMP/100 mL para Vitória do Mearim. Em seis pontos amostrados, sendo um ponto no município de Arari (P3) e todos os pontos em Vitória do Mearim (P1 a P5), totalizando 60% (n= 18) das amostras analisadas, podese constatar valores médios de E. coli acima do limite máximo estabelecido na legislação ambiental brasileira. Dos 10 pontos amostrados, foram isoladas de cada amostra dois morfotipos bacterianos diferentes caracterizados por colônias róseas e colônias incolores/transparentes. Os morfotipos bacterianos diferentes foram transferidos para testes bioquímicos em que foi possível constatar as características bioquímicas de 20 isolados compatíveis com a bactéria E. coli. Destes, foram detectados genes de virulência característicos de E. coli enterotoxigênica (ETEC) e E. coli enteropatogênica típica (EPEC-t) e atípica (EPECa). Os genes Stx1 e Stx2 não foram identificados no período de execução do estudo. Conclui-se que a qualidade microbiológica da água no trecho do baixo curso do rio Mearim pertencente a Bacia Hidrográfica do Rio Mearim sofre deterioração caracterizada por elevadas concentrações de coliformes totais, E. coli e diversificados patótipos diarreiogênicos (ETEC, EPEC-t e EPECa). A confirmação desse grupo de micro-organismos patogênicos representa risco epidemiológico, comprometendo diversos usos desse recurso hídrico, como a irrigação de frutas e hortaliças ingeridas cruas, pesca, dessedentação animal e recreação. Investimentos estruturais em saneamento básico são fundamentais para minimizar a degradação ambiental resultante das atividades antrópicas e para atuar preventivamente na saúde única. Adicionalmente, a recuperação das matas ciliares ao longo da bacia hidrográfica e manutenção da vegetação nestas áreas são medidas efetivas na redução do transporte de partículas do solo para os cursos dágua, e em consequência, acarreta a melhoria das características qualiquantitativas da água.

The Mearim River Basin stands out for its social, economic, environmental, energetic and cultural importance, especially for small rural producers who use this water source in agroproductive activities and for artisanal fishermen who withdraw their food and sustenance from this water resource. In this sense, the objective was to research diarrheagenic Escherichia coli in water of multiple uses as a model of single health surveillance. To carry out the study, water samples were collected at five points previously selected for the municipalities of Arari and Vitória do Mearim, state of Maranhão, which corresponded to an area of the lower course of the Mearim River. Samples were collected in triplicate from each point, totaling 30 samples, 15 samples per municipality. The samples were collected in sterile borosilicate glass bottles, with a capacity of 500 mL, in an aseptic manner and stored under sunlight in isothermal boxes with recyclable ice. For the quantification of total coliforms and E. coli, the enzymatic chromogenic system (Colilert, Idexx, USA) was used and the positive samples in this test proceeded to isolate and confirm the bacterium under study by means of conventional methodology (enrichment of the samples and biochemical identification of isolated colonies). DNA extraction from pure E. coli cultures was performed by heating followed by characterization using polymerase chain reaction (PCR) using the GoTaq® Colorless Master Mix Kit (Promega®) according to the manufacturer's recommendations. Of the analyzed samples, 100% (n = 30) had total coliforms with bacterial populations that varied from 7,701 to 24,196 NMP/100 mL for the municipality of Arari and 3,524 to 24,196 NMP/100 mL for Vitória do Mearim. In six sampled points, one point in the municipality of Arari (P3) and all points in Vitória do Mearim (P1 to P5), totaling 60% (n = 18) of the analyzed samples, one can verify average values of E. coli above the maximum limit established in Brazilian environmental legislation. Of the 10 sampled points, two different bacterial morphotypes were isolated from each sample, characterized by pink and colorless / transparent colonies. The different bacterial morphotypes were transferred to biochemical tests in which it was possible to verify the biochemical characteristics of 20 isolates compatible with the E. coli bacterium. Of these, virulence genes characteristic of E. coli enterotoxigenic (ETEC) and typical E. coli enteropathogenic (EPEC-t) and atypical (EPEC-a) were detected. The Stx1 and Stx2 genes were not identified at the time of the study. It is concluded that the microbiological quality of the water in the stretch of the low course of the Mearim River belonging to the Mearim River Basin suffers deterioration characterized by high concentrations of total coliforms, E. coli and diverse diarrhogenic genotypes (ETEC, EPEC-t and EPEC- The). The confirmation of this group of pathogenic microorganisms represents an epidemiological risk, compromising several uses of this water resource, such as irrigation of raw ingested fruits and vegetables, fishing, animal drinking and recreation. Structural investments in basic sanitation are fundamental to minimize the environmental degradation resulting from human activities and to act preventively in unique health. Additionally, the recovery of riparian forests along the hydrographic basin and the maintenance of vegetation in these areas are effective measures in reducing the transport of soil particles to water courses, and consequently, lead to the improvement of the qualitative and quantitative characteristics of the water

Assessment of lipolytic activity of isolated microorganisms from the savannah of the Tocantins / Avaliação da atividade lipolítica de microrganismos isolados do Cerrado tocantinense

Current study assesses the biodiversity and selects lipase-producer microorganisms with industrial interest, from the savannah of the state of Tocantins, Brazil. Seventeen pequi microorganisms (Caryocar brasiliense) were isolated in the decomposition stage and 35 microorganisms were retrieved from the soil fraction under the collected pequi. Yarrowia lypolitica strain was used as positive control in all assays. The 52 strains were subjected to tests in a solid medium with Tween 20 for checking halos formed by crystals, indicating lipase production by inoculated strains. Another test to confirm lipase producers was conducted in microplates with liquid medium and enriched with p-nitrophenyl palmitate (pNPP) monitored at 410 m. The AS16 and AP5 strains showed the highest activity for test conditions, namely, 0.072 and 0.067 U mL-1 respectively. Rates were higher than the lipase activity of Yarrowia lypolitica(0.052 U mL-1), a reference strain in current assay.(AU)

O atual estudo avalia a biodiversidade e selecionou microorganismos produtores de lipases de interesse industrial, a partir do cerrado tocantinense. O principal objetivo deste trabalho é avaliar a biodiversidade e selecionar microrganismos do cerrado tocantinense, produtores de lipases de interesse industrial. Foram isolados 17 microrganismos de Pequi (Caryocar brasiliense) em estágio de decomposição e também 35 microrganismos provenientes da fração do solo que se encontrava abaixo do pequi coletado. Foi utilizada uma cepa de Yarrowia lypolitica como controle positivo em todos os ensaios. Todas as 52 cepas foram submetidas a testes em meio sólido, utilizando Tween 20 para a verificação da presença de halos formados por cristais, indicando produção de lipase pelas linhagens inoculadas. Outro teste para confirmação dos produtores de lipase foi realizado em microplacas contendo meio líquido e enriquecido com pNPP (Palmitato de p-nitrofenila), monitorado a 410 m. As cepas AS16 e AP5 apresentaram as maiores atividades para as condições de ensaio a que foram submetidas: 0,072 e 0,067 U mL-1 respectivamente, sendo estes valores maiores que a atividade lipolítica da Yarrowia lypolitica (0,052 U mL-1), considerada como cepa referência para este trabalho.(AU)

Agroforestry systems, nutrients in litter and microbial activity in soils cultivated with coffee at high altitude

Agroforestry systems are an alternative option for sustainable production management. These systems contain trees that absorb nutrients from deeper layers of the soil and leaf litter that help improve the soil quality of the rough terrain in high altitude areas, which are areas extremely susceptible to environmental degradation. The aim of this study was to characterize the stock and nutrients in litter, soil activity and the population of microorganisms in coffee (Coffea arabica L.) plantations under high altitude agroforestry systems in the semi-arid region of the state of Pernambuco, Brazil. Samples were collected from the surface litter together with soil samples taken at two depths (0-10 and 10-20 cm) from areas each subject to one of the following four treatments: agroforestry system (AS), native forest (NF), biodynamic system (BS) and coffee control (CT).The coffee plantation had been abandoned for nearly 15 years and, although there had been no management or harvesting, still contained productive coffee plants. The accumulation of litter and mean nutrient content of the litter, the soil nutrient content, microbial biomass carbon, total carbon, total nitrogen, C/N ratio, basal respiration, microbial quotient, metabolic quotient and microbial populations (total bacteria, fluorescent bacteria group, total fungi and Trichoderma spp.) were all analyzed. The systems thatwere exposed to human intervention (A and BS) differed in their chemical attributes and contained higher levels of nutrients when compared to NF and CT. BS for coffee production at high altitude can be used as a sustainable alternative in the high altitude zones of the semi-arid region in Brazil, which is an area that is highly susceptible to environmental degradation.

Agroforestry systems, nutrients in litter and microbial activity in soils cultivated with coffee at high altitude

Agroforestry systems are an alternative option for sustainable production management. These systems contain trees that absorb nutrients from deeper layers of the soil and leaf litter that help improve the soil quality of the rough terrain in high altitude areas, which are areas extremely susceptible to environmental degradation. The aim of this study was to characterize the stock and nutrients in litter, soil activity and the population of microorganisms in coffee (Coffea arabica L.) plantations under high altitude agroforestry systems in the semi-arid region of the state of Pernambuco, Brazil. Samples were collected from the surface litter together with soil samples taken at two depths (0-10 and 10-20 cm) from areas each subject to one of the following four treatments: agroforestry system (AS), native forest (NF), biodynamic system (BS) and coffee control (CT).The coffee plantation had been abandoned for nearly 15 years and, although there had been no management or harvesting, still contained productive coffee plants. The accumulation of litter and mean nutrient content of the litter, the soil nutrient content, microbial biomass carbon, total carbon, total nitrogen, C/N ratio, basal respiration, microbial quotient, metabolic quotient and microbial populations (total bacteria, fluorescent bacteria group, total fungi and Trichoderma spp.) were all analyzed. The systems thatwere exposed to human intervention (A and BS) differed in their chemical attributes and contained higher levels of nutrients when compared to NF and CT. BS for coffee production at high altitude can be used as a sustainable alternative in the high altitude zones of the semi-arid region in Brazil, which is an area that is highly susceptible to environmental degradation.(AU)

Culturable diversity of halophilic bacteria in foreshore soils

Halophilic bacteria are commonly found in natural environments containing significant concentration of NaCl such as inland salt lakes and evaporated sea-shore pools, as well as environments such as curing brines, salted food products and saline soils. Dependence on salt is an important phenotypic characteristic of halophilic bacteria, which can be used in the polyphasic characterization of newly discovered microorganisms. In this study the diversity of halophilic bacteria in foreshore soils of Daecheon, Chungnam, and Saemangeum, Jeonbuk, was investigated. Two types of media, namely NA and R2A supplemented with 3%, 5%, 9%, 15%, 20% and 30% NaCl were used. More than 200 halophilic bacteria were isolated and BOX-PCR fingerprinting analysis was done for the typing of the isolates. The BLAST identification results showed that isolated strains were composed of 4 phyla, Firmicutes (60%), Proteobacteria (31%), Bacteriodetes (5%) and Actinobacteria (4%). Isolates were affiliated with 16 genera and 36 species. Bacillus was the dominant genus in the phylum Firmicutes, comprising 24% of the total isolates. Halomonas (12%) and Shewanella (12%) were also found as the main genera. These findings show that the foreshore soil of Daecheon Beach and Saemangeum Sea of Korea represents an untapped source of bacterial biodiversity.

DISSEMINAÇÃO AMBIENTAL EM PROPRIEDADES SUINÍCOLAS DA RESISTÊNCIA A ANTIMICROBIANOS UTILIZANDO A Escherichia coli COMO BIOMARCADORA

O objetivo deste estudo foi verificar a disseminação ambiental de cepas de Escherichia coli em propriedades suinícolas do Oeste de Santa Catarina e utilizá-la como biomarcadora para avaliar o perfil fenotípico da susceptibilidade aos antimicrobianos, a possível presença de ESBLs (Beta-Lactamases de Espectro Estendido) e genes responsáveis pela resistência às fluoroquinolonas. Foram utilizadas para o isolamento de E. coli o total de 306 amostras, sendo 103 amostras de fezes suínas, 105 de água e 98 de solo oriundas de propriedades suinícolas dos municípios com maior produção de suínos do oeste catarinense. Os isolados de E. coli foram submetidos ao antibiograma com os antimicrobianos: amoxicilina associada ao ácido clavulânico (20/10 g), ceftiofur (30 g), enrofloxacina (5 g), gentamicina (10 g), sulfametoxazol associado ao trimetoprim (1,25/23,75 g) e colistina (10 g). Os isolados também foram submetidos ao teste de disco aproximação indicador da produção de ESBLs e pesquisa via PCR dos genes blaCTY-M2, blaSHV-1, blaTEM-1, blaCTX-M2, blaOXA-1, blaPSE-1, responsáveis pela produção de ESBLs e dos genes qnrA, qnrB e qnrS que conferem resistência às quinolonas e fluoroquinolonas. O percentual de isolamento de E. coli encontrado para as amostras de fezes, água e solo foi de 66,02%, 30,48% e 35,71% respectivamente. Os maiores percentuais de resistência obtidos foram para os antimicrobianos sulfametoxazol associado ao trimetoprim (63,70%), colistina (45,19%) e enrofloxacina (39,26%). Quanto aos níveis de multirresistência foi possível observar que 37,04% dos isolados eram resistentes a três ou mais classes de antimicrobianos. Dos perfis de multirresistencia avaliados, o perfil A (GEM-SUT-ENO-COL) foi o mais comumente encontrado (16%). Detectamos valores de IRMA (Índice de Resistência Múltipla aos Antimicrobianos) acima de 0,2 em 78% das amostras multirresistentes. Dos 135 isolados foi possível detectar cepas produtoras de ESBLs (7,41%), onde destas, 60% apresentaram positividade para o gene blaTEM-1, 50% para o gene blaCMY-M2 e 90% para os genes qnrS. Das cepas resistentes à enrofloxacina não produtoras de ESBLs apresentaram positividade para o gene qnrS e qnrB, 17,39% e 2,17%, respectivamente e o gene qnrA não foi detectado. Os resultados obtidos neste estudo, utilizando a E. coli como biomarcadora, demonstraram a contaminação de amostras ambientais por microrganismos de origem fecal, além, dos altos índices de resistência, presença de genes produtores de beta-lactamases e de resistência a fluoroquinolonas, reforçando ainda mais a necessidade do uso consciente dos antimicrobianos e também do tratamento adequado de dejeto s e efluentes.

The objective of this study was to verify the environmental dissemination of strains of Escherichia coli in pig farms in the West of Santa Catarina state and to use it as a biomarker to evaluate the phenotypic profile of antimicrobial susceptibility, the possible presence of ESBLs (Extended Spectrum Beta-Lactamases) and genes responsible for quinolone resistance. A total of 306 samples were used for the isolation of E. coli, of which 103 samples were from swine feces, 105 of water and 98 of soil from pig farms of few municipalities with the largest production of pigs from the west of Santa Catarina. The isolates of E. coli were submitted to antimicrobial antibiotics: amoxicillin associated with clavulanic acid (20/10 g), ceftiofur (30 g), enrofloxacin (5 g), gentamicin (10 g), trimethoprim sulfamethoxazole (1.25/ 23.75 g) and colistin (10 g). The isolates were also submitted to the ESBL-test approximation and the PCR test of the genes blaCTY-M2, blaSHV-1, blaTEM-1, blaCTX-M2, blaOXA-1, blaPSE-1, responsible for the production of ESBLs and the qnrA, qnrB and qnrS genes that confer resistance to quinolones and fluoroquinolones. The percentage of E. coli isolates found for feces, water and soil samples was 66.02%, 30.48% and 35.71%, respectively. The highest percentages of resistance were obtained for antimicrobial agents sulfamethoxazole associated with trimethoprim (63.70%), colistin (45.19%) and enrofloxacin (39.26%). Regarding the multiresistance levels, it was possible to observe that 37.04% of the isolates were resistant to three or more classes of antimicrobials. Out of all multiresistant profiles evaluated, profile A (GEM-SUT-ENO-COL) was the most commonly found (16%). We detected values of IRMA (Multiple Resistance Index to Antimicrobials) above 0.2 in 78% of the multiresistant strains. Out of 135 isolates, it was possible to detect ESBLs producers (7.41%), of which 60% showed positivity for blaTEM-1 gene, 50% for the blaCMY-M2 gene and 90% for the qnrS genes. Of the non-ESBL-producing enrofloxacin-resistant strains, the qnrS and qnrB genes, 17.39% and 2.17%, respectively were positives, and the qnrA gene was not detected. The results obtained in this study, using E. coli as a biomarker, demonstrated the contamination of environmental samples by fecal microorganisms, in addition to high resistance indexes, the presence of beta-lactamase genes and resistance to fluoroquinolones, reinforcing the need for a more conscious use of the antimicrobials and also for proper treatment of animal waste.

Bactérias promotoras do crescimento vegetal e nitrogênio no estabelecimento e no desenvolvimento de Urochloa spp.

A inoculação de bactérias promotoras do crescimento vegetal pode ser uma alternativa sustentável na recuperação e manutenção de pastagens. Neste sentido, objetivou-se avaliar o efeito da inoculação de bactérias promotoras de crescimento de plantas nas características morfogênicas, estruturais e produtivas de três genótipos de Urochloa (U. brizantha cv. BRS Paiaguás, U. ruziziensis e U. brizantha cv. Xaraés). O experimento foi desenvolvido em delineamento inteiramente ao acaso, em casa de vegetação, com período experimental de 12 meses. Os tratamentos consistiram de cinco bactérias (sem bactéria, Azospirillum brasilense Ab-V5, Azospirillum brasilense Ab-V6, Pseudomonas fluorescens CCTB03, Pseudomonas fluorescens ET76 e Pantoea ananatis AMG521) e três níveis de nitrogênio (zero, 50 e 100 kg ha-1 de N), em um esquema fatorial 6x3. Os inóculos foram preparados na concentração final de 108 células mL-1 no Laboratório de Biotecnologia do Solo da Embrapa Soja, sendo misturados 15 mL de inóculo a cada quilo de sementes de cada capim e deixados secar à sombra por 30 minutos. Os vasos foram preenchidos com 15 dm3 de solo proveniente do arenito Caiuá. Em todos os vasos foram corrigidos os teores de fósforo, potássio e aplicado o equivalente a 20 kg ha-1 de N. Para caracterização morfogênica foram demarcados dois perfilhos por vaso diferidos por fios de arame colorido. Uma vez por semana foram mensurados a altura de pseudocolmo e comprimento de cada lâmina foliar, registrando-se as ocorrências de senescência, quebra (corte), morte e expansão da lâmina foliar dos perfilhos demarcados. Essas medidas foram utilizadas na determinação das taxas de alongamento de colmo (TAlC), taxa de aparecimento de folhas (TApF), filocrono, taxa de alongamento de folhas (TAlF), taxa de senescência (TSeF), duração de vida da folha (DVF) e número de folhas vivas (NFV) por perfilho. Quando as plantas atingiram, em média, 35 cm de altura, foram cortadas, deixando-se 15 cm como resíduo. Após o corte, as amostras foram pesadas e secas em estufa para determinação da massa seca. Essas amostras foram moídas e determinada a concentração de proteína bruta e digestibilidade da matéria seca. Para a mensuração da clorofila foi utilizado o equipamento clorofiLOG - CFL1030 da Falker. Foi determinada a produção de massa de raízes e a geometria das raízes. Quando cabível, as médias entre os grupos controle (sem bactérias ou sem adubação nitrogenada) e os grupos tratados foram comparados utilizando o teste de Dunnet e as médias entre os tratamentos foram comparadas entre si pelo teste de t student. Em todas as análises estatísticas utilizou-se PROC GLM do pacote estatístico Statistical Analisys System SAS V 9.2 (SAS Institute Inc. Cary, CA), a 5%. De modo geral, para U. brizantha cv. BRS Paiaguás e Xaraés, os melhores desempenhos foram obtidos com as estirpes P. fluorescens CCTB03 e P. ananatis AMG521, nos parâmetros de taxa de alongamento foliar e do caule e número de perfilhos basais. Para U. ruziziensis, o melhor desempenho foi em relação à duração e taxa de renovação das folhas e de senescência foliar, favorecidos pelas estirpes AMG521, Ab-V5 e Ab-V6, indicando especificidade de estirpes com os genótipos de braquiárias. Verificou-se, também, diferença na interação entre BPCV e a adubação nitrogenada, pois em U. brizantha os efeitos foram aditivos, enquanto em U. ruziziensis foram competitivas. Os resultados indicam viabilidade de inoculação de braquiárias com estirpes elite de BPCV, com impactos positivos na produção de biomassa forrageira, com possibilidade de redução ou aumento de eficiência de uso de N-fertilizante. Observou-se efeito do uso das BPCV na produção de massa de forragem, massa de raízes e concentração de proteína bruta do capim-paiaguás. Em relação às estirpes, novamente destaca-se P. fluorescens CCTB03 e P. ananatis AMG521, as quais promoveram incrementos apenas com a adubação à base de nitrogênio e associadas a 50 kg de N, com menor efeito associado a 100 kg de N. No geral, as bactérias promotoras do crescimento vegetal beneficiam o crescimento e desenvolvimento de espécies do gênero Urochloa, podendo ser uma nova opção no manejo em busca da sustentabilidade das plantas forrageiras nos trópicos.

Inoculation of plant growth-promoting bacteria can be a sustainable alternative in pastures recovery and maintenance. In this sense, the objective of this study was to evaluate the inoculation effect of plant growth promoter bacteria on the morphogenic, structural and productive characteristics of three Urochloa genotypes (U. brizantha cv. BRS Paiaguás, U. ruziziensis and U. brizantha cv. Xaraes). The treatments consisted of five bacteria (without bacterium, Azospirillum brasilense Ab-V5, Azospirillum brasilense Ab-V6, Pseudomonas fluorescens CCTB03, Pseudomonas fluorescens ET76 and Pantoea ananatis AMG521) and three doses of nitrogen (0, 50 and 100 kg ha-1 N) in a 6x3 factorial scheme. Bacteria were identified and inoculum prepared with a final concentration of 108 cells mL-1 in the Biotechnology Laboratory Emulsion soil, then 15 mL of inoculum was mixed to 1 kg of each grass seed and allowed to dry in the shade for 30 minutes. Experimental pots were filled with 15 dm3 of Caiuá sandstone. In all them, phosphorus and potassium contents were corrected and the equivalent of 20 kg of N ha-1 was applied. For morphogenic characterization, two tillers per pots were demarcated by colored wire and once a week the pseudocolus height and length of each leaf blade were measured, recording the occurrence of senescence, breaking (cutting), death and expansion of the leaf blade. These measures were used to determine steam elongation rates (SER) leaf renewal rate (LAR), phyllochron, leaf elongation rate (LER), senescence rate (SR), leaf life span (LLS) and number of live leaves (NLL) per tiller. When the plants reached an average of 35 cm in height, they were cut, leaving 15 cm as residue. After cutting, the samples were weighed and dried in an oven to determine the dry mass. These samples were ground and the crude protein concentration and dry matter digestibility were determined. Chlorophyll measurement was performed using the chlorofiLOG - CFL1030 equipment from Falker. Root mass production and root geometry were determined. When appropriate, the means between the control groups (without bacteria or without nitrogen fertilization) and treated groups were compared using the Dunnet test and the means among treatments were compared by the t student test. In all statistical analyzes, PROC GLM was used from the statistical package "Statistical Analisys System" - SAS V 9.2 (SAS Institute Inc. Cary, CA), at 5%. In general, for U. brizantha cv. BRS Paiaguás and Xaraés, the best performances were observed with the strains P. fluorescens CCTB03 and P. ananatis AMG521, in the parameters of leaf and steam elongation rate and number of basal tillers. For U. ruziziensis, the best performance was in relation to the duration and leaf renewal rate as well as leaf senescence, favored by strains AMG521, Ab-V5 and Ab-V6, indicating strains specificity with Urochola genotypes. It was also verified difference in the interaction between PGPB and nitrogen fertilization, because in U. brizantha the effects were additive, whereas in U. ruziziensis they were competitive. The results indicate the feasibility of Brachiaria inoculation with PGPB elite strains, with positive impacts on the forage biomass production, perhaps reducing or increasing the efficiency of N-fertilizer use. PGPB effect on the forage mass production, root mass and crude protein concentration of paiaguás grass were observed. In relation to the strains, again we highlight P. fluorescens CCTB03 and P. ananatis AMG521, which promoted increases only with nitrogen fertilization and associated with 50 kg of N, with lower effect associated with 100 kg of N. Overall, the plant growth-promoting bacteria benefit the growth and development of Urochloa genus species and may be a new option in the management in the sustainability search of forage plants in the tropics.

Emissão de óxido nitroso, metano e amônia de excretas bovinas em pastos de capim-braquiária em sistema silvipastoril ou monocultivo

Many problems associated with the use of high-grain diets are reported by growers and scientists as the negative effects associated with acidosis. In order to improve the ruminal conditions, studies have been carried out to find an optimal level of fiber to be included in these diets, especially in the so-called non-voluminous diets. Therefore, the objective of this work was to evaluate the effects of the inclusion of physically effective fiber (NDF) from bulks in diets containing whole grains of corn, replacing the pellet, under ingestive, digestive and ruminal parameters. The experiment was carried out at the Animal Science Department of the Federal University of Viçosa. Five rumen fistulated, uncastrated male Nellore cattle with a mean of 393 ± 9 kg and age of 14 months were used. The experimental design was in a 5 x 5 Latin square, consisting of five diets, five animals and five experimental periods. The diets were based on whole corn grain with inclusion of increasing levels of sugarcane in natura, being constituted respectively by: Control (CON) - Diet with 85% of whole grain corn and 15% of a mineral- pore protein; D5 - Diet with 85% of whole grain corn, 5% of sugar cane in natura and 10% of a mineral protein supplement; D15 - Diet with 75% of whole grain corn, 15% of sugar cane in natura and 10% of a mineral protein supplement; D25 - Diet with 65% of whole grain corn, 25% of sugar cane in natura and 10% of a protein mineral supplement; D35 - Diet with 55% of whole grain corn, 35% of sugar cane in natura and 10% of a protein mineral supplement. The experimental periods had a duration of 20 days (14 days for adaptation and six days of collection). The first three days of sampling were used for the sampling of omasal digests, spot collection of feces, and sampling of samples for estimation of concentrations of ammonia and organic acids. Ruminal pH was also measured. On the fourth and sixth day of the collection period, emptying was performed on the full and empty spot of the rumen, respectively. During these days samples were also collected for the isolation of ruminal microorganisms. The physically effective NDF content of each diet was measured at the end of each experimental period with the aid of a set of three sieves called Pen State Particle Sepatator (PSPS), which had 19, 8 and 4 mm sieves. Statistical analyzes were performed using the SAS® MIXED procedure (Version 9.4). The averages were compared using the Dunnett test, assuming 5% for the type I error, and the linear and quadratic effects were tested for inclusion levels of NDF in the diet and the ammonia concentration was evaluated as a repeated measure. The organic matter (OM), neutral detergent insoluble fiber corrected for ash and protein (FDNcp) and neutral detergent insoluble fiber corrected for ash and potentially digestible protein (NDFcpPD), crude protein (CP), ethereal extract , non-fibrous carbohydrates (CNF) and starch responded in a linear decreasing or quadratic manner as a function of the levels of NDF of roughage. The digestibilities of all the constituents reduced with the inclusion of NDF of roughage, with the exception of the potentially digestible NDFcp (PD). The ruminal pH responded in an increasing linear fashion to the addition of voluminous in the diet. The concentration and the pool of propionate linearly reduced and the concentration of butyrate and the acetate pool tended to reduce and elevate, respectively. The concentration of ruminal ammoniacal nitrogen increased linearly. Thus, a level of NDF from volumine of 20.47 g / kg, corresponding to 5% of sugarcane, can be used instead of pellets in whole corn diets, in order to improve the parameters nutritional and metabolic characteristics of this type of food matrix.

One of the problems associated with livestock in Brazil is the emission of greenhouse gases (GHG), responsible for global warming, mainly due to the significant national cattle herd. In addition to enteric methane, animal excreta are sources GHG for atmosphere. This study was conducted with the objective of quantifying N2O, CH4 and NH3 emissions from bovine excreta in pastures of brachiaria grass in silvopastoral (SSP) and monoculture (MONO) systems during the rainy and dry periods of the year. The study was carried out in the Experimental Field José Henrique Bruschi, in the city of Coronel Pacheco, from February to April and from July to October 2017. A randomized complete block design was used, with 3 blocks and 2 replicates per treatment within each block, in a split-plot scheme, considering a factorial 3x2 (3 excreta types and 2 systems) in the plot and period of the year (rainy or dry) as subplot effect. An area within each system was previously isolated from the entrance of animals for 1 year and divided into 18 plots that received the excreta. Dung and urine were obtained from 12 crossbred cows, being 6 cows were kept in grazing in each of the systems for 30 days before excreta collection. At moment of collection, the animals were contained and the dung and urine referring to each of the two systems were homogenized and sampled in triplicate for further analysis of dung and urine total nitrogen and the volatile solids content of dung. Subsequently, 1 L of fresh urine and 1.6 kg of fresh dung were deposited in the respective plots. During the rainy season, urine application increased N2O fluxes in both systems, while dung application increased CH4 fluxes. During the dry period, both N2O and CH4 fluxes were substantially reduced. In general, the fluxes of N2O and CH4 in SSP were higher than the fluxes in Mono. Considering the type of excreta applied in the rainy season, it was observed that the emission factor (EF) of N2O in the area treated with urine was significantly higher than in the area treated with dung (P<0.05) in SSP. Regarding to the effect of the type of system, it was observed that in the rainy period, the EF of N2O for urine and the EF of CH4 for dung in SSP were significantly higher (P<0.05) than in the Mono. The volatilization of NH3 from both dung and urine was higher during the dry period. Regarding to EF of NH3, it was higher (P <0.05) in Mono and in the dry period when urine was applied, there being no difference between systems with dung application. During the period of higher emissions of N2O, there was emission of 0.4% of the N applied in the form of urine in SSP and 0.04% in Mono, with emissions below 0.05% for dung in both systems. Regarding to CH4, there was emission of 0.03% of the volatile solids applied in the form of dung in SSP and 0.01% in Mono, during the period of greatest emission, with no significant emissions with the application of urine. The EF of NH3 for urine ranged from 1.7% to 4.3% in SSP and from 8.3% to 17.1% in Mono, with EF for dung ranging from 1.2% to 5.8% in SSP and from 1.8% to 3.6% in Mono. The present study demonstrates that the emissions of N2O, CH4 and NH3 are influenced by the system of land use, type of excreta and season of the year. In addition, the emission factor of N2O, CH4 and NH3 in both systems, under these conditions, is significantly below that estimated by the IPCC at the global level.

Soil microbial biomass in organic farming system

Agricultural production systems have to combine management practices in order to sustain soil's profitability and quality. Organic farming is gaining worldwide acceptance and has been expanding at an annual rate of 20% in the last decade, accounting for over 24 million hectares worldwide. Organic practices avoid applications of synthetic fertilizers and pesticides, rely on organic inputs and recycling for nutrient supply, and emphasize cropping system design and biological processes for pest management, as defined by organic farming regulation in the world. In comparison with conventional farming, organic farming has potential benefits in improving food quality and safety. Plant production in organic farming mainly depends on nutrient release as a function of mineralization processes in soils. The build-up of a large and active soil microbial biomass is important pool of accessible nutrients, therefore, is an important priority in organic farming. In organic farming, there is positive effect of quantity and quality of inputs of organic residues on soil microbial biomass. In this way, the organic systems are extremely important for the increase of the soil fertility and the maintenance of the environmental sustainability.

A produção agrícola tem de combinar práticas para prover a sustentabilidade do solo. A agricultura orgânica está ganhando aceitação mundial e cresce à taxa anual de 20% na última década, contabilizando mais de 24 milhões de hectares. As práticas orgânicas evitam o uso de fertilizantes sintéticos e pesticidas, enfatiza a aplicação de matéria orgânica, como também a reciclagem de nutrientes e de processos biológicos para manejo de pragas, através das regras dos sistemas orgânicos no mundo. Em comparação com a agricultura convencional, os sistemas orgânicos têm potencial de melhorar a qualidade e a segurança dos alimentos. A produção das plantas no sistema orgânico depende da liberação de nutrientes pelo processo de mineralização microbiana no solo. A construção de uma grande e ativa biomassa microbiana é um importante reservatório de nutrientes disponíveis. Dessa forma, isso é uma prioridade no sistema orgânico. Em sistemas orgânicos, há efeitos positivos da quantidade e da qualidade das fontes de carbono orgânico sobre a biomassa microbiana do solo. Nesse sentido, as práticas do sistema orgânico são extremamente importantes para o aumento da fertilidade do solo e para a manutenção da sustentabilidade ambiental.

Soil microbial biomass in organic farming system

Agricultural production systems have to combine management practices in order to sustain soil's profitability and quality. Organic farming is gaining worldwide acceptance and has been expanding at an annual rate of 20% in the last decade, accounting for over 24 million hectares worldwide. Organic practices avoid applications of synthetic fertilizers and pesticides, rely on organic inputs and recycling for nutrient supply, and emphasize cropping system design and biological processes for pest management, as defined by organic farming regulation in the world. In comparison with conventional farming, organic farming has potential benefits in improving food quality and safety. Plant production in organic farming mainly depends on nutrient release as a function of mineralization processes in soils. The build-up of a large and active soil microbial biomass is important pool of accessible nutrients, therefore, is an important priority in organic farming. In organic farming, there is positive effect of quantity and quality of inputs of organic residues on soil microbial biomass. In this way, the organic systems are extremely important for the increase of the soil fertility and the maintenance of the environmental sustainability.

A produção agrícola tem de combinar práticas para prover a sustentabilidade do solo. A agricultura orgânica está ganhando aceitação mundial e cresce à taxa anual de 20% na última década, contabilizando mais de 24 milhões de hectares. As práticas orgânicas evitam o uso de fertilizantes sintéticos e pesticidas, enfatiza a aplicação de matéria orgânica, como também a reciclagem de nutrientes e de processos biológicos para manejo de pragas, através das regras dos sistemas orgânicos no mundo. Em comparação com a agricultura convencional, os sistemas orgânicos têm potencial de melhorar a qualidade e a segurança dos alimentos. A produção das plantas no sistema orgânico depende da liberação de nutrientes pelo processo de mineralização microbiana no solo. A construção de uma grande e ativa biomassa microbiana é um importante reservatório de nutrientes disponíveis. Dessa forma, isso é uma prioridade no sistema orgânico. Em sistemas orgânicos, há efeitos positivos da quantidade e da qualidade das fontes de carbono orgânico sobre a biomassa microbiana do solo. Nesse sentido, as práticas do sistema orgânico são extremamente importantes para o aumento da fertilidade do solo e para a manutenção da sustentabilidade ambiental.

Soil microbial biomass in organic farming system

Agricultural production systems have to combine management practices in order to sustain soil's profitability and quality. Organic farming is gaining worldwide acceptance and has been expanding at an annual rate of 20% in the last decade, accounting for over 24 million hectares worldwide. Organic practices avoid applications of synthetic fertilizers and pesticides, rely on organic inputs and recycling for nutrient supply, and emphasize cropping system design and biological processes for pest management, as defined by organic farming regulation in the world. In comparison with conventional farming, organic farming has potential benefits in improving food quality and safety. Plant production in organic farming mainly depends on nutrient release as a function of mineralization processes in soils. The build-up of a large and active soil microbial biomass is important pool of accessible nutrients, therefore, is an important priority in organic farming. In organic farming, there is positive effect of quantity and quality of inputs of organic residues on soil microbial biomass. In this way, the organic systems are extremely important for the increase of the soil fertility and the maintenance of the environmental sustainability.

A produção agrícola tem de combinar práticas para prover a sustentabilidade do solo. A agricultura orgânica está ganhando aceitação mundial e cresce à taxa anual de 20% na última década, contabilizando mais de 24 milhões de hectares. As práticas orgânicas evitam o uso de fertilizantes sintéticos e pesticidas, enfatiza a aplicação de matéria orgânica, como também a reciclagem de nutrientes e de processos biológicos para manejo de pragas, através das regras dos sistemas orgânicos no mundo. Em comparação com a agricultura convencional, os sistemas orgânicos têm potencial de melhorar a qualidade e a segurança dos alimentos. A produção das plantas no sistema orgânico depende da liberação de nutrientes pelo processo de mineralização microbiana no solo. A construção de uma grande e ativa biomassa microbiana é um importante reservatório de nutrientes disponíveis. Dessa forma, isso é uma prioridade no sistema orgânico. Em sistemas orgânicos, há efeitos positivos da quantidade e da qualidade das fontes de carbono orgânico sobre a biomassa microbiana do solo. Nesse sentido, as práticas do sistema orgânico são extremamente importantes para o aumento da fertilidade do solo e para a manutenção da sustentabilidade ambiental.