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Bibliographic Details
Main Author: João Paulo Ramos Costa
Format: Artículo científico
Language:en
Published: Universidade Estadual de Maringá 2015
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Online Access:https://www.redalyc.org/articulo.oa?id=303138476002
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  • Relative chlorophyll contents in the evaluation of the nutritional status of nitrogen from xaraes palisade grass and determination of critical nitrogen sufficiency index João Paulo Ramos Costa Gregory de Paula Caputti Leandro Galzerano Wilton Ladeira da Silva Ana Claudia Ruggieri Euclides Braga Malheiros Agrociencias SPAD Fertilization chlorophyll meter Urochloa brizantha nutritional status The nutritional status of xaraes palisade grass with SPAD chlorophyll meter and the critical nitrogen sufficiency index (cNSI) in the dry and rainy seasons were assessed. The experiment was conducted in a completely randomized design with four treatments (50, 100, 200 and 400 kg N ha-1), three replicates and two seasons: dry and rainy. All variables had a high nonlinear relationship with their predictors (p < 0.001). Total nitrogen (TN) reached a plateau at doses 262.0 and 514.8 kg of N ha-1 and the concentration of TN in the plant was 1.88 and 1.93% respectively during the rainy and dry season. Relative chlorophyll content (RCC) reached a plateau at 46.05 and 53.65 SPAD units in the rainy and dry seasons, respectively. The production of dry matter (DM) showed maximum response to nitrogen fertilization at 209.5 and 229.1 kg N ha-1 during the rainy and dry season respectively. The nitrogen sufficiency index (NSI) reached the plateau at 0.85 and 0.99 in the rainy and dry season respectively. All variables showed high linear correlation (r = 0.71 to 0.99). The xaraés palisade grass’s cNSI is 0.85 and the chlorophyll meter may be used as a nutritional N management tool for the grass. 2015 artículo científico 1806-2636 https://www.redalyc.org/articulo.oa?id=303138476002 en http://www.redalyc.org/revista.oa?id=3031 Acta Scientiarum. Animal Sciences application/pdf Universidade Estadual de Maringá Acta Scientiarum. Animal Sciences (Brasil) Num.2 Vol.37