358-10 Sensor-Based Nitrogen Applications Out-Performed Producer-Chosen Rates for Corn In On-Farm Demonstrations.

See more from this Division: S04 Soil Fertility & Plant Nutrition
See more from this Session: Site Specific Nutrient Management: I
Wednesday, October 19, 2011: 10:35 AM
Henry Gonzalez Convention Center, Room 211
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Peter Scharf1, Kent Shannon2, Kenneth A. Sudduth3 and Newell Kitchen3, (1)214 Waters, University of Missouri, Columbia, MO
(2)University of Missouri Extension, Columbia, MO
(3)USDA-ARS Cropping Systems & Water Quality Research Unit, Columbia, MO
Optimal nitrogen (N) fertilizer rate for corn can vary substantially within and among fields. Crop reflectance sensors offer the potential to diagnose crop N need and control N application rates at a fine spatial scale. Our objective was to evaluate the performance of sensor-based variable-rate N applications relative to a constant N rate chosen by the producer. Fifty-five on-farm demonstrations were conducted from 2004 to 2008. Sensors were installed on the producer’s nitrogen application equipment and used to direct variable-rate sidedress nitrogen applications to corn at growth stages ranging from V6 to V16. A fixed N rate chosen by the cooperating producer was also applied. Relative to the producer’s N rate, sensors increased partial profit and yield while reducing N use. Our results confirm that sensors can choose N rates for corn that perform better than rates chosen by producers.
See more from this Division: S04 Soil Fertility & Plant Nutrition
See more from this Session: Site Specific Nutrient Management: I