Portable chlorophyll meter can estimate the nitrogen sufficiency index and levels of topdressing nitrogen in common bean

The nitrogen sufficiency index (NSI) obtained by using a portable chlorophyll meter is a practical alternative to evaluate the N levels in plants. This study aimed at determining the appropriate NSI value for leaves of common bean plants, in order to define the need and amount of N to be applied as...

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Detalles Bibliográficos
Autores: Silveira, Pedro Marques da, Gonzaga, Augusto Cesar de Oliveira
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2017
País:Brasil
Institución:Universidade Federal de Goiás (UFG)
Repositorio:Pesquisa Agropecuária Tropical (Online)
Idioma:inglés
OAI Identifier:oai:ojs.revistas.ufg.br:article/42128
Acceso en línea:https://revistas.ufg.br/pat/article/view/42128
Access Level:acceso abierto
Palabra clave:Phaseolus vulgaris
nitrogen fertilization
SPAD-502.
adubação nitrogenada
Descripción
Sumario:The nitrogen sufficiency index (NSI) obtained by using a portable chlorophyll meter is a practical alternative to evaluate the N levels in plants. This study aimed at determining the appropriate NSI value for leaves of common bean plants, in order to define the need and amount of N to be applied as topdressing, using the Minolta SPAD-502 portable chlorophyll meter. Three field experiments were conducted using a randomized blocks design, with four replications. Nitrogen doses were applied as topdressing and compared with a treatment in which a high dose of N was used as a reference to calculate the NSI, whose value was 95 %. According to the results observed using the chlorophyll meter and the NSI, for each 0.1 percentage point increase in the NSI to reach the adequate level (95 %), it is necessary to apply 1.1-1.5 kg ha-1 of topdressing N.