Microbial diversity can be used to assess the impact of agricultural practices on the long-term sustainability of cropping systems. The aim of this study was to investigate changes in soil bacterial diversity as a result of the impact of different soil tillage and crop rotation systems in an oxisol of southern Brazil. Bacterial diversity was examined in the 0-10 cm layer in two field experiments by analyzing soil DNA using 16S rDNA-DGGE profiles. Experiment one consisted of a long-term 26-year trial with four soil tillage management systems: (1) no-tillage (NT), (2) disc plow (DP), (3) field cultivator (FC), and (4) heavy-disc harrow (DH), all under soybean (summer)/wheat (winter) crop succession. Experiment two consisted of a short-term 10-year trial with DP and NT and three crop rotations (CR) including grasses, legumes and green manures. Cluster analysis of the 16S rDNA sequences revealed that the main effect on clustering was attributed to differences in soil tillage management systems. The Shannon index confirmed greater bacterial diversity under NT, followed by the FC, DH and DP. Therefore, diversity decreased as tillage practices intensified. The evenness index demonstrated uniformity of the profiles of the bacterial communities, with dominance of a few communities, regardless of soil tillage and crop rotation. Different crop rotations had only minor effects on bacterial diversity, what could be related to a previous fallow period. The results suggest that bacterial diversity analyzed by DGGE may be useful as bioindicator of the changes caused by soil tillage.

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Mastite bovina é caraterizada por inflamação da glândula mamária, geralmente em resposta à infecção bacteriana, compromete quali-quantitativamente a produção leiteira. Este estudo objetivou verificar a atividade antibacteriana in vitro do extrato hidroalcoólico da casca da romã sobre bactérias isoladas de leite bovino. As colônias de Staphylococcus spp. foram ressuspendidas a escala 6 de MacFarland e ajustada a sua concentração por espectrofotometria UV visível na concentração de 10 mL-1. Os extratos foram avaliados em quintuplicata, em sete concentrações: de 4mg mL-1 até 0,0625 mg.mL-1. A sensibilidade dos isolados microbianos foi determinada utilizando o teste de difusão em disco e os resultados que apresentaram zonas de inibição correspondentes a valores a partir de 15 mm, foram considerados sensíveis. Os resultados foram avaliados pelo método ANOVA, teste de Tukey 5%, utilizando o SISVAR 5.3 -DEX/UFLA. Adicionalmente o extrato foi avaliado quanto à atividade antioxidante, teores de fenóis e flavonoides totais. Para tanto o extrato foi diluído em sete concentrações: de 25 a 1000µg.mL-1, e avaliado em triplicata. O crescimento bacteriano foi inibido a partir da concentração de 4mg.mL-1 e a ação antioxidante foi verificada a partir de 50µg.mL-1, com valores correspondentes a 4.62%, atingindo platô de 64,90% na concentração de 500µg.mL-1. Na avaliação da atividade captadora de radicais, empregando o radical livre DPPH, o extrato demonstrou atividade antioxidante (IC50%= 378,80µg/mL). Porém, não foi possível correlacionar a atividade antioxidante aos teores de fenóis e flavonoides. Talvez a presença de outras substâncias alcaloides e taninos presentes no extrato, possam ter sido as responsáveis pela atividade antioxidante encontrada. Conclui-se que o extrato hidroalcoólico de Punica granatum Linn. apresenta atividade antimicrobiana contra Staphylococcus spp., demonstrando potencial benefício para o controle da mastite bovina.

In recent decades, the contamination of the atmosphere has occupied a prominent place causing countless harm, making it a public health problem which jeopardises in a serious way the hospital environment, bringing a potential risk of hospital infection (HI). The aim of the study was to identify and classify hospital fungal contaminants in units of high complexity. The assessment of air quality was carried out in four categories of environment: High Complexity Intensive Care Adult Unit (AICU), Newborn (NICU), hallways and corridors and external area. The monitoring of these environments was conducted in the morning and afternoon, the air filters were removed and transferred to plates with culture media BDA and incubated at 28°C, isolated and identified. Ten genera of filamentous fungi, pathogenic and toxigenic were found. It was found that, in the afternoon and in the morning, the contamination was significantly lower in AICU (23.3 CFU/m 3), with 55.3 CFU/m 3 in NICU. In none of the environments studied, the average concentration of filamentous fungi exceeded the maximum recommended by Resolution N°. 09 of the National Agency for Sanitary Vigilance of 750 CFU/m 3 .

Soil monitoring is fundamental to promote sustainability agroecosystems. It is necessary to consider indicators that bring together biological, physical, chemical and inter-relational attributes. Pfeiffer chromatography (PC) represents an important method for soil diagnosis, so the present study aims to analyze it in order to contribute to its validation. The soil samples of 12 production systems were evaluated in quintuplicate. The chromas were elaborated using Whatman no 4 filter paper, and the soil extract was performed by sodium hydroxide solution 1%. The results were obtained using revealing solution (AgNO3 0.5%) ascension by capillarity, and the chrome zones: central, internal, medium and external were correlated to soil penetration, chemical, biological and enzymatic parameters, respectively. Variance analysis was applied to the results that presented normal distribution and the means were compared by Scott-Knott test. T-test for Spearman correlations and principal component analysis were used to evaluate the correlations. There was negative correlation between the central zone and the average penetration resistance within the range 0-40 cm in depth. The internal, medium and external zones presented positive correlation with organic matter, carbon microbial biomass, and enzymatic activities, respectively. Quality standard features such as coloration, size and proportion of zones, presence of enzymatic clouds, peaks and radial lines were also confirmed. Thus, the standardization developed by this study contributed to validation of PC. Since PC is a low-cost and easy-to-perform method, it proves to be a useful tool allowing farmers autonomy to monitoring different agricultural systems, contributing to their production sustainable.

The yield of soybean was influenced by the chemical and microbiological properties of the soil, which was favored by management techniques that promote improvement in soil quality. The objective of this study was to evaluate soybean yield, chemical and microbiological quality of the soil as a function of biological fertilization and soil cover conditions. The experiment was conducted in both crops seasons 2015/16 and 2016/17 with experimental design in randomized blocks, with the agronomic characteristics of the soybean analyzed as a function of the factors of biological fertilization and soil cover conditions, as well as the chemical and microbiological indicators of the soil, besides the two factors mentioned earlier, fragment of forest. It was observed higher height of plants, pods with three grains, leaf area and yield of soybean cultivated on Crotalaria ochroleuca, followed by Pennisetum glaucum. Biological fertilizer, P. glaucum and C. ochroleuca promoted increases in the fertility of soil cultivated with soybean, mainly potassium, and contributed to reduce carbon losses, indicated by lower basal respiration and soil metabolic quotient. Based on the results, we conclude that the soybean presented highest grain yield with C. ochroleuca, and the biological fertilization and cover plants increased the chemical and microbiological quality of the soil. These techniques can be implemented in the soybean farming system.

RESUMO -A mastite é um dos fatores que mais gera prejuízos à produção e industrialização do leite. O objetivo deste trabalho foi isolar a espécie Staphylococcus aureus das amostras de leite provenientes de 63 animais portadores de mastite, e verificar o seu perfil de sensibilidade antimicrobiana aos antibióticos comerciais e ao extrato de própolis à 30%. Dos 63 animais avaliados, 38 (60,32%) apresentaram crescimento de Staphylococcus aureus. Quanto ao teste de sensibilidade antimicrobiana, os antibióticos mais eficientes foram gentamicina (10 g), cefalexina (30 g) e ciprofloxacina (10 µg) com 100% de eficácia, seguida de norfloxacina (94,6%). Houve 35 (92,10%) animais com sensibilidade ao extrato alcoólico de própolis a 30%, com diâmetros de inibição entre 6 e 18 mm frente a volumes de 40L e 60 L. A investigação da sensibilidade antimicrobiana in vitro para cepas de Staphylococcus aureus isoladas de mastite bovina é de grande importância antes da indicação do seu tratamento terapêutico. O uso do extrato alcoólico de própolis a 30% na terapia antimicrobiana pode ser uma alternativa, pois seus componentes conferem-lhe grande valor na medicina natural popular e preventiva.Palavras-Chave: Antibiótico, mastite clínica, mastite subclínica, resistência.ABSTRACT -Mastitis is one of the factors that cause damage to production and processing milk. The aim of this study was to isolate the species Staphylococcus aureus from milk samples from 63 animals with mastitis, and check your profile antimicrobial sensitivity to antibiotics and the extract of propolis at 30%. Of 63 animals evaluated, 38 (60.32%) showed growth of Staphylococcus aureus. As for testing of antimicrobial sensitivity test, the most efficient antibiotics were gentamicin (10 g), cephalexin (30 g) and ciprofloxacin (10 g) with 100% efficiency, followed by norfloxacin (94.6%). There were 35 (92.10%) animals with sensitivity to the extract of propolis 30% with inhibition diameters between 6 and 18 mm in 40 L and 60 L. The investigation of in vitro antimicrobial susceptibility to Staphylococcus aureus isolated from bovine mastitis is extremely valuable to their treatment. The use of extract of propolis 30% in the antimicrobial therapy may be an alternative, because its components gives it excellent value in natural medicine and preventive.

The objective of this work was to evaluate the influence of different doses of spent coffee grounds on soil microorganisms responsible for nutrient cycling and the development of corn crop under no-tillage. The trial was conducted in a field at the State Center for Agricultural Professional Education Fernando Costa, in a randomized block with 4 treatments, with increasing doses, 0, 3, 6 and 9 t ha-1 of coffee grounds. Microbial biomass carbon (CBM), baseline respiration (RBS), microbial and metabolic quotient (qMIC and qCO2), plant development (corn) and productivity were evaluated. At the dose of 9 t ha-1 of spent coffee grounds, there was an increase in organic matter and microbial biomass (219.01) and qMIC (1.5). With increased microbial activity, the development of the plant was 20% higher compared to the control, plant height (2.21) and stem diameter (2.99). Consequently, the productivity was 42 bags ha-1 higher than the control. Thus, we can conclude that spent coffee grounds can be a viable alternative for use as organic fertilizer in agriculture.