Soil nitrogen availability indices as predictors of sugarcane nitrogen requirements

Autor(es)

Mariano, Eduardo ; Otto, Rafael ; Montezano, Zaqueu F. ; Cantarella, Heitor ; Trivelin, Paulo C. O.

• Tipo de documento: Artigo Científico
• Fonte: EUROPEAN JOURNAL OF AGRONOMY; v. 89, p. 25-37, SEP 2017.
• Citações Web of Science: 6

Resumo

Nitrogen recommendation systems for sugarcane (Saccharum spp.) generally does not consider the N supply from soil. Identifying a reliable soil test for estimating N availability is crucial to avoid yield losses or environmental pollution. Therefore, the objective of this study was to correlate and calibrate N availability indices with field based measures of soil N supply. Between 2006 and 2013, 15 trials for rate-response to N fertilizer by sugarcane ratoons were performed in sao Paulo, the main sugarcane-producing state in Brazil. The following indices were tested: KMnO4 oxidizable C, hot KCl extractable N, phosphate borate buffer distillable N, NaOH distillable N, Illinois Soil N Test, organic C, total N, mineral N, anaerobic incubation, soil respiration, substrate induced respiration, microbial biomass C, metabolic quotient, microbial quotient, and gross N mineralization. The indices were then correlated with sugarcane yield (Y-0N) and N content of the crop (N-0N) in N unfertilized plots, relative yield (RY), and the N rate predicted to achieve 90% of the RY (NR 90%RY). Although weak correlations were found between Y-0N with anaerobic incubation, total N, and soil respiration, as well as between NON and anaerobic incubation, no index correlated with RY or NR 90%RY. Grouping sites based on soil texture or byproduct management did not improve prediction of RY. Therefore, we concluded that none of the fifteen laboratory indices is a reliable predictor of soil N supply, and hence could not be used to adjust N fertilization rate for sugarcane. (AU)

• Processo FAPESP: 11/14372-1 - Mineralização do nitrogênio do solo como parâmetro para adubação nitrogenada da cana-de-açúcar
• Beneficiário: Paulo Cesar Ocheuze Trivelin
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Regular
• Processo FAPESP: 11/07955-0 - Predição da necessidade de fertilizante nitrogenado pela cana-de-açúcar e reações do nitrogênio orgânico e mineral dissolvido em palha e solo de canaviais
• Beneficiário: Eduardo Mariano
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 08/56147-1 - Nutrição nitrogenada de cana-de-açúcar com fertilizantes ou bactérias diazotróficas
• Beneficiário: Heitor Cantarella
• Modalidade de apoio: Auxílio à Pesquisa - Programa BIOEN - Temático
• Processo FAPESP: 02/10534-8 - Rendimento da cana-de-açúcar em ciclos consecutivos associado ao efeito residual e as transformações de N e S no solo, em sistema conservacionista
• Beneficiário: Paulo Cesar Ocheuze Trivelin
• Modalidade de apoio: Auxílio à Pesquisa - Temático