caa a22 4500 445864435 CHVBK 20180317145453.0 cr unu---uuuuu 170323e20111201xx s 000 0 eng 10.1007/s11119-011-9224-7 doi (NATIONALLICENCE)springer-10.1007/s11119-011-9224-7 Regional model for nitrogen fertilization of site-specific rainfed corn in haplustolls of the central Pampas, Argentina [Elektronische Daten] [M. Gregoret, M. Díaz Zorita, J. Dardanelli, R. Bongiovanni] 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 0-161kgNha−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. Springer Science+Business Media, LLC, 2011 Variable fertilizer rates nationallicence Nitrogen nationallicence Spatial statistics nationallicence Semi-arid regions nationallicence AON : Agronomically-optimum N rate nationallicence BD : Soil bulk density nationallicence EC : Soil electrical conductivity nationallicence EON : Economically-optimum N rate nationallicence HP : High productivity nationallicence LP : Low productivity nationallicence MP : Medium productivity nationallicence MZ : Management zone nationallicence Nd : Available Nitrogen (soil available N-NO3 at planting+applied N) nationallicence NUEf : Agronomic Fertilizer N use efficiency nationallicence P : Soil extractable phosphorus nationallicence PA : Precision agriculture nationallicence SAW : Soil available water content at sowing nationallicence SOM : Soil organic matter nationallicence TN : Total soil nitrogen nationallicence VRF : Variable rates of fertilizer nationallicence Gregoret M. Technical Area, AACREA Cordoba Norte, Sarmiento 1236, Ciudad autonoma de Buenos Aires, Argentina aut Díaz Zorita M. CONICET-FAUBA and Merck Crop Bioscience Argentina, Pilar, Argentina aut Dardanelli J. INTA Manfredi, Córdoba, Argentina aut Bongiovanni R. INTA Manfredi, Córdoba, Argentina aut Precision Agriculture Springer US; http://www.springer-ny.com 12/6(2011-12-01), 831-849 1385-2256 12:6<831 2011 12 11119 https://doi.org/10.1007/s11119-011-9224-7 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11119-011-9224-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gregoret M. Technical Area, AACREA Cordoba Norte, Sarmiento 1236, Ciudad autonoma de Buenos Aires, Argentina aut NATIONALLICENCE 700 1- Díaz Zorita M. CONICET-FAUBA and Merck Crop Bioscience Argentina, Pilar, Argentina aut NATIONALLICENCE 700 1- Dardanelli J. INTA Manfredi, Córdoba, Argentina aut NATIONALLICENCE 700 1- Bongiovanni R. INTA Manfredi, Córdoba, Argentina aut NATIONALLICENCE 773 0- Precision Agriculture Springer US; http://www.springer-ny.com 12/6(2011-12-01), 831-849 1385-2256 12:6<831 2011 12 11119 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer