Regional model for nitrogen fertilization of site-specific rainfed corn in haplustolls of the central Pampas, Argentina

Authors
Gregoret, M. C.; Diaz Zorita, Martin; Dardanelli, J.; Bongiovanni, R. G.
Publication Year
2011
Language
English
Format
article
Status
Published version
Description
In semi-arid regions, soil water and nitrogen (N) are generally limiting factors for corn (Zea mays L.) production; hence, implementation of appropriate N fertilization strategies is needed. The use of precision agriculture practices based on specific site and crop properties may contribute to a better allocation of fertilizer among management zones (MZ). The aim of this study was to develop a model for diagnosis of N availability and recommendation of N fertilizer rates adjusted to MZ for dryland corn crops growing in Haplustolls. The model considered variability between MZ by including site-specific variables [soil available water content at sowing (SAW) and Available Nitrogen (soil available N-NO3 at planting + applied N, Nd)] using spatial statistical analysis. The study was conducted in Córdoba, Argentina in Haplustolls and consisted in four field trials of N fertilizer (range 0-161 kg N ha-1) in each MZ. The MZ were selected based on elevation maps analysis. Grain yields varied between MZ and increased with larger SAW and Nd at sowing. Grain responses to Nd and SAW in any MZ were not different between sites, allowing to fit a regional model whose parameters (Nd, Nd2, SAW, SAW2) contributed significantly (p < 0.001) to yield prediction. Agronomical and economically optimum N rates varied among MZs. However, the spatial variability of optimum N rates among MZs within sites was not enough to recommend variable N fertilizer rates instead of a uniform rate. Variable N fertilizer rates should be recommended only if variability in SAW and soil N among MZ is greater than that found in this work. © 2011 Springer Science+Business Media, LLC.
Fil: Gregoret, M. C.. Asociación Argentina de Consorcios Regionales de Experimentación Agrícola; Argentina
Fil: Diaz Zorita, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomía; Argentina
Fil: Dardanelli, J.. Instituto Nacional de Tecnología Agropecuaria; Argentina
Fil: Bongiovanni, R. G.. Instituto Nacional de Tecnología Agropecuaria; Argentina
Subject
NITROGEN
SEMI-ARID REGIONS
SPATIAL STATISTICS
VARIABLE FERTILIZER RATES
Agricultura
Agricultura, Silvicultura y Pesca
CIENCIAS AGRÍCOLAS
Access level
Restricted access
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/59611