Efeitos dos ácidos húmicos provenientes de aterro sanitário em plantas

• Ano de defesa: 2014
• Autor(a) principal: Morozesk, Mariana
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Biologia Vegetal; UFES; Programa de Pós-Graduação em Biologia Vegetal
• Palavras-chave em Português: Cytotoxicity; Test Allium cepa; Growth analysis and oxidative stress; Citotoxicidade; Teste Allium cepa; Análise de crescimento e estresse oxidativo; Zea mays; Fisiologia vegetal; Citologia; Anatomia; Stress oxidativo; Ácido húmico; Agronomia; 57
• Link de acesso: http://repositorio.ufes.br/handle/10/1234

The process of biological treatment of landfills leachate results in the generation of large amounts of sludge, characterized by containing high levels of organic matter. The chemical fractionation of organic matter results in humic acids (HA) that has been demonstrated with high efficiency on the plant growth promoting improvements on development. This work aimed to evaluate the effects of exposure of plants to different doses of HA extracted from sludge landfill by chemical and biological analysis, to elucidate the effects of this organic material and minimize the potential risks of using sludge in natura. Chemical characterization of HA showed high carbon and nitrogen levels, which can consist in an important source of nutrients for plants. Furthermore, effects were observed in the absorption rates and in factors of bioconcentration and translocation of some nutrients. Regarding the analysis of antioxidant, enzymes were possible to observe different effects of HA with the each dose applied. Furthermore, cytogenetic abnormalities were detected in meristematic cells and F1. Actions on plant growth are also reported through significant increases in root area and height. In general, growth data showed an investment in the plant shoot, probably associated with the improved efficiency of the root system. Moreover, alterations on thickness of the epidermis were also reported. In this context, despite the evidenced nutritional benefits and the activity of HA on plant metabolism, their biological effects on oxidative stress enzymes and its cytotoxic capacity need to be clarified. Due to the complexity of the compound, the use of chemical, genetic, enzymatic, physiological and anatomical analyzes was an important tool in evaluating the application of humic acids in plants.