Instituto de Ciências Agrárias - CAF
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11784
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Resultados da Pesquisa
Item Relationships between soil quality indicators, redox properties, and bioactivity of humic substances of soils under integrated farming, livestock, and forestry(Revista Ceres, 2018-07) Baldotto, Marihus Altoé; Baldotto, Lílian Estrela BorgesOnce it is stabilized in the soil, organic matter minimizes limitations of Brazilian Oxisols, such as low cation exchange capacity, low nutrient availability, toxicity due to high aluminum content, and phosphate adsorption. Moreover, humified organic matter fractions are bioactive. It is, therefore, important to evaluate the biostimulant ability of compounds present in soil carbon stocks to develop sustainable technologies for tropical agriculture based on renewable natural resources. The objective of this research was to correlate some soil quality indicators, redox properties, and bioactivity of humic acids isolated from integrated farming, livestock, and forestry systems aiming to understand the mechanisms involved in plant stimulation by humified organic matter. Carbon stocks and their stability were determined from oxidation by dichromatometry and iodometry, respectively. Bioactivity was assessed using yield data of corn indicator plants. The results indicated that when native-like forests were reintroduced instead of pastureland, soil carbon stocks and their stability increased along with overall improvements in soil fertility, chemical and physical properties, and soil biodiversity. The bioactivity of humic substances isolated from soils used in integrated crop, livestock, and forestry management was higher than that of soils derived from pastures or eucalyptus alone.Item Ácidos húmicos(Revista Ceres, 2014-11) Baldotto, Marihus Altoé; Baldotto, Lílian Estrela BorgesQual é a estrutura molecular das substâncias húmicas? Ainda não foi possível encontrar a resposta. Há muita controvérsia e pouco consenso sobre as estruturas dessas substâncias. Destacam-se dois pontos principais: o acúmulo de informações e os desafios metodológicos. Esta revisão objetivou reunir informações sobre a natureza dos ácidos húmicos e suas funções nos ecossistemas naturais e agrários, visando ao manejo e à conservação, bem como às oportunidades tecnológicas para o desenvolvimento de novos insumos para a agricultura tropical.Item Selection of diazotrophic bacteria isolated from wastewater treatment plant sludge at a poultry slaughterhouse for their effect on maize plants(Revista Ceres, 2018-01) Lozada, Jorge Avelino Rodriguez; Silveira, Klever Cristiano; Silva, Libério Junio da; Baldotto, Marihus Altoé; Baldotto, Lílian Estrela BorgesThe economic and environmental costs of nitrogen fertilization have intensified the search for technologies that reduce mineral fertilization, for example atmospheric nitrogen-fixing (diazotrophic) bacteria inoculation. In this context, the present study addressed the isolation and quantification of diazotrophic bacteria in the sludge from treated wastewater of a poultry slaughterhouse; a description of the bacteria, based on cell and colony morphology; and an assessment of growth and N content of maize plants in response to inoculation. Sixteen morphotypes of bacteria were isolated in six N-free culture media (JMV, JMVL, NFb, JNFb, LGI, and LGI-P). The bacteria stained gram-positive, with 10 rod- and six coccoid-shaped isolates. To evaluate the potential of bacteria to promote plant growth, maize seeds were inoculated. The experiment consisted of 17 treatments (control plus 16 bacterial isolates) and was carried out in a completely randomized design with six replicates. The experimental units consisted of one pot containing two maize plants in a greenhouse. Forty-five days after planting, the variables plant height, leaf number, stem diameter, root and shoot fresh and dry weight, and N content were measured. The highest values were obtained with isolate UFV L-162, which produced 0.68 g total dry matter per plant and increased N content to 22.14 mg/plant, representing increments of 74 and 133%, respectively, compared with the control. Diazotrophs inhabit sludge from treated wastewater of poultry slaughterhouses and can potentially be used to stimulate plant development and enrich inoculants.Item Initial performance of pineapple and utilization of rock phosphate applied in combination with organic compounds to leaf axils(Revista Ceres, 2011-06) Baldotto, Marihus Altoé; Giro, Validoro Bazoni; Baldotto, Lílian Estrela Borges; Canellas, Luciano Pasqualoto; Velloso, Carlos XavierRock phosphates have low solubility in water, but good solubility in acid. The use of organic compounds together with these phosphorus sources applied to the basal leaf axils of pineapple can increase the solubility of this phosfate source and increase the P availability to the crop. A greenhouse experiment was conducted using Araxá rock phosphate (10 g) in combination or not with solutions containing increasing concentrations of humic acids (0 to 40 mmol L-1 of carbon), with or without citric acid (0.005 mmol L-1), applied to basal leaf axils of pineapple cv. Pérola. Growth and nutritional characteristics of aerial plant parts were assessed. Growth rates of aerial parts and N, P, K, Ca and Mg contents increased curvilinearly with increasing concentration of carbon in the form of humic acids. Maximum values were found for the concentration of 9.3 mmol L-1 of carbon combined with 0.005 mmol L-1 of citric acid and natural phosphate.Item Initial growth of maize in response to application of rock phosphate, vermicompost and endophytic bacteria(Revista Ceres, 2012-02-06) Baldotto, Lílian Estrela Borges; Silva, Luiz Gonzaga Jr. Santos; Canellas, Luciano Pasqualoto; Olivares, Fábio Lopes; Baldotto, Marihus AltoéDue to the high energy requirement and demand for non-renewable resources for the production of chemical fertilizers, added also to the environmental impact caused by the use of such products, it is important to intensify research on bio-based agricultural inputs. The use of nitrogen-fixing endophytic and phosphate solubilizing bacteria can provide these nutrients to the plants from the air and poorly soluble phosphorus sources, such as phosphate rock. The objective of this study was to evaluate the nutrition and initial growth of maize (Zea mays L.) in response to the inoculation of nitrogen-fixing and rock phosphate solubilizing endophytic bacteria, in single or mixed formulation, applied with vermicompost. The treatments containing bacteria, both diazotrophic and phosphate solubilizing, when compared to controls, showed higher levels of leaf nitrogen and phosphorus in maize, as well as higher growth characteristics. The application of vermicompost showed synergistic effect when combined with endophytic bacteria. Thus, the innovation of the combination of the studied factors may contribute to the early development of maize.Item Desempenho inicial do milho em resposta a ácidos húmicos isolados de esterco bovino e cama de aviário(Semina: Ciências Agrárias, 2014-11-30) Melo, Raphael Oliveira de; Baldotto, Marihus Altoé; Baldotto, Lílian Estrela BorgesO milho é cultivado em todo o país, produzindo quantidades variáveis conforme o investimento em tecnologia. Dentre essas tecnologias, destaca-se o uso de sementes melhoradas, associadas com adequado manejo integrado dos fatores de produção, tais como a correção e fertilização dos solos, a irrigação, o controle fitossanitário e de competidores e, mais recentemente, o uso de biorreguladores, buscando otimizar a produtividade. De forma análoga aos reguladores de crescimento sintéticos, como as auxinas, as substâncias húmicas da matéria orgânica apresentam um efeito estimulante em plantas. Contudo, a bioatividade e a concentração ótima das substâncias húmicas variam de acordo com as espécies vegetais e com matérias primas das quais elas foram isoladas. Por essas razões, este trabalho teve como objetivo estudar o crescimento e desenvolvimento do milho, em resposta à aplicação de diferentes concentrações de ácidos húmicos, via tratamento de sementes. Os tratamentos constituíramse de duas fontes de ácidos húmicos (esterco bovino e cama de aviário) utilizando cinco concentrações (0, 10, 20, 30 e 40 mmol L-1 de C) das respectivas soluções, aplicado via tratamentos de sementes em um bioensaio conduzido em casa de vegetação. Ao final do experimento (45 dias após a germinação), as plantas foram avaliadas biometricamente e nutricionalmente. Os resultados mostraram incrementos significativos no crescimento e desenvolvimento da parte aérea e do sistema radicular, e acumulo significativo dos nutrientes N e P com a aplicação de ácidos húmicos isolados de esterco bovino, sendo que os mesmos não ocorreram com a aplicação de ácidos húmicos isolados de cama de aviário. Assim o uso de bioestimulantes à base de ácidos húmicos isolados de esterco bovino é positivo e complementar comparativamente aos insumos geralmente usados no tratamento de sementes de milho.Item Prospecting for sludge bacteria from a poultry slaughterhouse, with potential for degrading organic substances(Semina: Ciências Agrárias, 2016-08-21) Lozada, Jorge Avelino Rodriguez; Silveira, Klever Cristiano; Silva, Libério Junio da; Baldotto, Marihus Altoé; Baldotto, Lílian Estrela BorgesThe sludge produced in wastewater treatment plants of slaughterhouses is a rich source of chemical, organic, and microbiological constituents that can be biotechnologically exploited. The purpose of this study was to (i) conduct a chemical analysis of the sludge, and (ii) isolate, quantify, and describe the amylolytic, cellulolytic, ligninolytic, proteolytic, and keratinolytic bacteria in the sludge. Sludge samples were collected at the wastewater treatment plant of the Francap SA poultry company. The nutrient contents, C/N ratio, and pH were determined. For the bacterial count, 10 g sludge was diluted in 90 mL saline solution, which was serially diluted to 10-12. Aliquots of 100 µL of each dilution were transferred to selective media for isolation of bacteria that degrade organic substances. The colony-forming units were determined for each culture medium. Individual colonies were purified and characterized morphologically. The sludge contained 9.5, 1.21, and 0.45 dag kg-1 of N, P, and K, respectively. Fifty-two isolates were purified and characterized, with 2.11 × 1012 to 9.55 ×1015 colony-forming units per g sludge. In conclusion, the sludge generated in poultry slaughterhouse wastewater treatment plants is a rich source of organo-mineral constituents and bacteria with biotechnological potential for degrading organic substances.Item Root growth of Arabidopsis thaliana (L.) Heynh. treated with humic acids isolated from typical soils of Rio de Janeiro State, Brazil(Revista Ceres, 2011-07-06) Baldotto, Marihus Altoé; Baldotto, Lílian Estrela Borges; Muniz, Rafael Carvalho; Dobbss, Leonardo BarrosSoil characteristics related to the genesis, land use and management are important factors in water dynamics in watersheds. This study evaluated physical, morphological and pedogenetic attributes related to water yield potential in small watersheds in Guarapari, ES, Brazil. The following representative profiles were selected, morphologically described and sampled in area of Atlantic Forest domain: Lithic Udifolists, Oxyaquic Udifluventes, Typic Paleudults, Typic Hapludults, Typic Hapludox, Oxic Dystrudepts and Typic Endoaquents. Samples were collected in the soil profiles for physical analysis. Measurements of field-saturated hydraulic conductivity and soil penetration resistance were perfomed in some profiles, which were under different uses. The Endoaquents of Limão Creek can be considered efficient as temporary water reservoirs. However, the use of artificial drainage tends to reduce this effect. Differential erosion was detected by the sand texture on the surface of the Typic Paleudults due to the low degree of clay flocculation, slope, high resistance to the penetration and low hydraulic conductivity of the Bt horizon, making it necessary to adopt soil management practices to increase the water infiltration. Under pasture, mainly in the cattle trails where the trampling is more intense, there was high resistance to penetration in the superficial layers of the Typic Hapludults. The Typic Hapludox have the greatest potential for water yield in the small watersheds because of its greater extent in the headwaters and their morphological and physical characteristics, which can result in increased aquifer recharge.Item The plant stimulant humic acid extracted from organic waste recycled by composting combined with liming and fertilization(Semina: Ciências Agrárias, 2016-04-22) Baldotto, Marihus Altoé; Rocha, Jayna Eloy da; Andrade, Francine Dias Paes; Del Giúdice, Marcos Paiva; Baldotto, Lílian Estrela BorgesThe disposal of organic waste can be an environmental problem; on the other hand, this waste can be the raw material for the production of biostimulants, among other recycling processes. The objective of this study was to recycle waste bovine manure and poultry litter through composting and isolate its humic acids in order to test their use, in the presence and absence of liming and fertilization, on corn plants as indicators. The experiment was conducted in a randomized block design with four replications. The experimental unit was a vase of 1 dm3 filled with soil that received treatments generated by the combination of the factors under study: humic acids via seed, liming, and fertilization. After thirty days of the experiment, growth characteristics were measured to estimate the initial performance of the indicator corn plants in response to the treatments. The results showed that the combination of chemical fertilization with humic acids extracted from organic compounds increased the plants development. In conclusion, the use of biostimulants based on humic substances is positive and complementary to fertilizers used in agriculture, forming a superior combination. Such use is also recommended because it allows for the recycling of organic waste via composting, as well as the preparation of biostimulants for added technical, and potentially economic, value.Item Oxidation capacity as an index of organic matter stability from sediments of the Paraíba do Sul river-estuarine gradient(Química Nova, 2011-04-01) Baldotto, Marihus Altoé; Canellas, Luciano Pasqualoto; Rosa, Raul Castro Carriello; Range, Thiago Pessanha; Salomão, Marcos Sarmet Moreira de Barros; Rezende, Carlos EduardoThe hummus composition and it redox properties have been used to evaluate the organic matter quality from natural systems. The objectives of this study were the fractionation of the organic matter and the determination of the oxidation capacity of humic acids to evaluate the organic matter quality of sediments from a gradient fluvial-estuarine in the Brazilian Southeast. The carbon/nitrogen and humic acid/fulvic acid relationships of the organic matter and of the oxidation capacity of humic acids were positively correlated and followed the order: estuarine bordered mangroves ≅ fluvial bordered urban center and pasture > estuarine bordered pasture ≅ marine.
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