Curva de absorção de nutrientes na mandioca em função de doses de nitrogênio

Detalhes bibliográficos
Ano de defesa: 2013
Autor(a) principal: Santos, Nádia Souza dos
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal de Roraima
Brasil
PRPPG - Pró-reitoria de Pesquisa e Pós-Graduação
POSAGRO - Programa de Pós-Graduação em Agronomia
UFRR
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: http://repositorio.ufrr.br:8080/jspui/handle/prefix/593
Resumo: The objective of this study was modeling the absorption of nutrients in cassava submitted to different levels of nitrogen along the productive cycle. The experimental design was in blocks at random in scheme of split plots, with four replications, the parcels comprised levels of nitrogen (0, 30, 60, 150 e 330 kg ha-1) divided in two application at 30 and 60 days after emergence (DAE), and the subplots of the evaluation times (120, 150, 180, 210, 240, 270 and 300 DAE). The collected plant material was ground and later subjected to analysis to obtain the extraction of leaf nutrient content (N, P, K, Ca, Mg, S, Fe, Mn and Zn). At 120, 150, 180, 240 and 300 DAE were assessed levels of chlorophyll a and b using the chlorophyll meter SPAD- 502, aerial productivity (kg ha-1), stem diameter (cm), length of the central lobe (cm), petiole length (cm), leaf width (cm) and root yield in kg ha-1. The levels of N applied in coverage increased the foliar levels of N, P, K, Mg, Mn and Zn; high levels decreased the foliar levels of Ca and S. The application N reduces the Fe content. With the aging of plants foliar contents N, K, Mg and Mn reduced. The chlorophyll concentration was positively correlated with the N content in cassava leaves and productivity of roots. The use of portable chlorophyll meter is a promising tool to assess the nutritional status of nitrogen in cassava. The levels N and age of plant provide positive linear increase in productivity of shoot, stem diameter and productivity of the roots. In The highest level of productivity of tuberous roots, at eight months old, the accumulation order of the nutrients in cassava is of: nitrogen> calcium> potassium> magnesium> phosphorus> sulfur> manganese> iron> zinc.