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Bacteria belonging to the genus Bacillus were isolated from soil samples of Parana´State, Brazil, with the aim of evaluating their potential biological control of soybean seed pathogens. Strain PRBS-1 was selected, showing similar effectiveness to that of the strain AP-3, used as a reference due to its known antibiotic potential. The sequencing of the ribosomal 16S rRNA gene confirmed that both strains belong to the species B. subtilis, although showing high genetic diversity in relation to this species. Both strains inhibited five soybean seed pathogenic fungi in vitro, Rhizoctonia solani, Colletotrichum truncatum, Sclerotinia sclerotiorum, Macrophomina phaseolina and Phomopsis sp. Furthermore, the metabolites of AP-3 increased production of root hairs, while the metabolites of PRBS-1 stimulated outgrowth of lateral roots in soybean. The antibiotic effect of both strains seemed to be related to compounds of the iturin group, while the root growth promotion by PRBS-1 was at least partially related to the production of indoleacetic acid. The results have shown the potential of using selected strains of B. subtilis in the biological control of seed pathogens, as well as in promoting soybean growth.

This paper presents a framework based on machine learning algorithms to predict nutrient content in leaf hyperspectral measurements. This is the first approach to evaluate macro- and micronutrient content with both machine learning and reflectance/first-derivative data. For this, citrus-leaves collected at a Valencia-orange orchard were used. Their spectral data was measured with a Fieldspec ASD FieldSpec® HandHeld 2 spectroradiometer and the surface reflectance and first-derivative spectra from the spectral range of 380 to 1020 nm (640 spectral bands) was evaluated. A total of 320 spectral signatures were collected, and the leaf-nutrient content (N, P, K, Mg, S, Cu, Fe, Mn, and Zn) was associated with them. For this, 204,800 (320 × 640) combinations were used. The following machine learning algorithms were used in this framework: k-Nearest Neighbor (kNN), Lasso Regression, Ridge Regression, Support Vector Machine (SVM), Artificial Neural Network (ANN), Decision Tree (DT), and Random Forest (RF). The training methods were assessed based on Cross-Validation and Leave-One-Out. The Relief-F metric of the algorithms’ prediction was used to determine the most contributive wavelength or spectral region associated with each nutrient. This approach was able to return, with high predictions (R2), nutrients like N (0.912), Mg (0.832), Cu (0.861), Mn (0.898), and Zn (0.855), and, to a lesser extent, P (0.771), K (0.763), and S (0.727). These accuracies were obtained with different algorithms, but RF was the most suitable to model most of them. The results indicate that, for the Valencia-orange leaves, surface reflectance data is more suitable to predict macronutrients, while first-derivative spectra is better linked to micronutrients. A final contribution of this study is the identification of the wavelengths responsible for contributing to these predictions.

BackgroundUpwelling systems are characterised by an intense primary biomass production in the surface (warmest) water after the outcrop of the bottom (coldest) water, which is rich in nutrients. Although it is known that the microbial assemblage plays an important role in the food chain of marine systems and that the upwelling systems that occur in southwest Brazil drive the complex dynamics of the food chain, little is known about the microbial composition present in this region.Methodology/Principal FindingsWe carried out a molecular survey based on SSU rRNA gene from the three domains of the phylogenetic tree of life present in a tropical upwelling region (Arraial do Cabo, Rio de Janeiro, Brazil). The aim was to analyse the horizontal and vertical variations of the microbial composition in two geographically close areas influenced by anthropogenic activity (sewage disposal/port activity) and upwelling phenomena, respectively. A lower estimated diversity of microorganisms of the three domains of the phylogenetic tree of life was found in the water of the area influenced by anthropogenic activity compared to the area influenced by upwelling phenomena. We observed a heterogenic distribution of the relative abundance of taxonomic groups, especially in the Archaea and Eukarya domains. The bacterial community was dominated by Proteobacteria, Cyanobacteria and Bacteroidetes phyla, whereas the microeukaryotic community was dominated by Metazoa, Fungi, Alveolata and Stramenopile. The estimated archaeal diversity was the lowest of the three domains and was dominated by uncharacterised marine Crenarchaeota that were most closely related to Marine Group I.Conclusions/SignificanceThe variety of conditions and the presence of different microbial assemblages indicated that the area of Arraial do Cabo can be used as a model for detailed studies that contemplate the correlation between pollution-indicating parameters and the depletion of microbial diversity in areas close to anthropogenic activity; functional roles and geochemical processes; phylogeny of the uncharacterised diversity; and seasonal variations of the microbial assemblages.

RESUMOBacillus subtilis, bactéria habitante natural do solo, produz antibióticos, enzimas e fitohormonios que proporcionam benefícios para as plantas. Essa espécie microbiana é também descrita como rizobactéria promotora de crescimento de plantas (RPCP). Sementes de milho, algodão e soja foram inoculadas com células de B. subtilis formulado com farinha de ostras objetivando-se avaliar a emergência e o desenvolvimento das plantas. A inoculação proporcionou aumento de emergências em algodão e soja. Além disso, a inoculação com o produto biológico incrementou significativamente a produção de massa seca, na parte aérea do milho. Os teores de fósforo e nitrogênio foram maiores no tecido foliar de milho, inoculados com a bactéria e farinha de ostras, comparando-se com a testemunha. A interação do resíduo orgânico com a bactéria proporcionou ganhos no crescimento e nutrição das plantas. A inoculação de sementes com B. subtilis, formulado com o resíduo orgânico, apresentou-se como uma alternativa tecnológica viável para a inoculação de sementes.Termos para indexação: Rizobactérias, nutrição de plantas, emergência, resíduos orgânicos. ABSTRACTBacillus subtilis is a soil bacteria able to synthesize antibiotics, enzymes and phytohormones importants for plant growth. This specie is also classified in plant growth as promoting rhizobacteria (PGPR). A biological product containing oyster meal and cells of B. subtilis was inoculated in seeds of corn, cotton and soybean. This inoculation increased emergence in cotton and soybean. The growth of corn was stimulated by seed inoculation with B. subtilis and organic amendment. The concentration of phosphorus and nitrogen significantly increased in the corn treated with the product. The interaction bacteria with organic amendment provided increments in plant growth. The inoculation of seeds with B. subtilis and amendments is promising technological alternative for seed treatment.

BackgroundUnderstanding normal gait requires allowing for variations in normal patterns by the sex, age, and species in question. Therefore, the aim of this study was to evaluate kinetic and temporospatial parameters in clinically healthy sheep from three different age groups with a pressure-sensing walkway. The sheep were judged to be healthy based on the results of complete physical and orthopaedic examinations and had no history of lameness. Twenty-one clinically healthy female Santa Ines sheep were divided into three groups: G1 – seven animals, aged from 8 to 12 months and weighing 19.5-33 kg; G2 - seven individuals, aged from 2 to 4 years and weighing 26.5-42 kg; and G3 - seven sheep, aged more than 5 years and weighing 37.3-45 kg. The animals were examined from two directions: first on the left side and then on the right side of the handler. The data from the first five valid trials in each direction were collected for each sheep and analysed using the designated software. A trial was considered valid if the sheep walked within the correct velocity (1.1-1.3 m/s) and acceleration (from −0.15 to 0.15 m/s2) ranges. The peak vertical force (PVF), vertical impulse (VI), gait cycle time, stance time, swing time, stride length, and the percentage body weight distribution among the four limbs were determined.ResultsNo significant differences were observed, in either the forelimbs or the hind limbs, between the left and right sides or between the two directions for any of the variables. No significant temporospatial differences were found among the groups. Significant PVF (%BW) differences were observed in the forelimbs (G1 > G3) and hind limbs (G1 > G3), and significant VI differences were observed in the forelimbs (G1 > G3).ConclusionsYoung healthy sheep differ from older sheep in the vertical forces they create when walking at the same velocity on a pressure-sensing walkway.

OBJETIVO: avaliar os efeitos de um programa educativo e assistencial frente a reincidência de gestação em adolescentes. MÉTODOS: estudo descritivo e retrospectivo, realizado no setor de Planejamento Familiar da Universidade Federal de São Paulo a partir de dados coletados em 264 prontuários de adolescentes que tinham como antecedente ao menos uma gravidez anterior a matrícula. RESULTADOS: os dados revelam que a menarca ocorreu, em média, aos 12,2 anos, a sexarca aos 15 e a primeira gravidez um ano após. Ao se matricularem no programa 73,5% possuíam uma gestação e 2% duas. O condom e os hormonais foram os contraceptivos mais utilizados. A reincidência de gravidez foi observada em 4,9% das adolescentes. CONCLUSÕES Os dados encontrados reforçam a importância do oferecimento de programas de planejamento familiar, que englobem a educação e a assistência com oferta do método contraceptivo, voltados a adolescentes.

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