Qualidade fisiológica e atividade enzimática de sementes de milho armazenadas

• Ano de defesa: 2012
• Autor(a) principal: Heberle, Elaine
• Orientador(a): Araújo, Eduardo Fontes
• Banca de defesa: Borges, Eduardo Euclydes de Lima e , Galvão, João Carlos Cardoso , Araújo, Roberto Fontes
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fitotecnia
• Departamento: Plantas daninhas, Alelopatia, Herbicidas e Resíduos; Fisiologia de culturas; Manejo pós-colheita de
• País: BR
• Palavras-chave em Português: Armazenamento; Germinação; Vigor; Atividade enzimática
• Palavras-chave em Inglês: Storage; Germination, Vigor; Enzymatic activity
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA
• Link de acesso: http://locus.ufv.br/handle/123456789/1187

The most important challenge of storing seeds is the maintenance of physiological quality obtained after the harvest until the sowing. The main environmental factors that affect seed quality during this period are the temperature and relative humidity. The objective was to evaluate the effect of three storage environments in the physiological quality and in the enzymatic activities of corn seeds during storage. Two lots of corn seeds, cultivar BR 106, were stored in paper packing in the environments: A1) cold chamber (12±2°C/60±5%RH), A2) uncontrolled environment (average 21,6°C/±71%RH) and A3) controlled chamber (30±2°C/70 ±5%RH). Evaluations were performed at first and at 90, 180, 270, 360 and 450 days of storage through germination test, first count of germination, accelerated aging, emergence in sand, electrical conductivity, water content and enzymatic activity of peroxidase, catalase and α-amylase. The experiment was a completely randomized design in a split plot, with a 3x2 factorial arrangement (environments x lots) in the plots, and days of storage in the subplots, with four replications. The seed physiological quality was reduced during storage and affected by environmental conditions, with greater decreases in those seed stored in an environment with higher temperatures. The lot 1 had an initial germination of 99%, and after 450 days, it was reduced to 92, 87 and 75%; and the lot 2 had 97% initial germination, at 90, 86 and 69% after 450 days storage, in the environments A1, A2 and A3, respectively. Considering the standard of minimum germination for marketing of certified corn seeds of 85%, they can be stored for 450 days in cold chamber, or up to 360 days in uncontrolled environment, under the conditions studied. In environments with high temperature, the corn seeds can only be stored for up to 180 days, avoiding the marketed of lots below the commercial standard. The enzymatic activities of peroxidase, catalase and α-amylase allow identification of the deterioration process of the corn seeds.