Late Season N Application Method Effect on Grain Protein, 2016

Abstract

Nitrogen fertilizer is normally applied later in the season around flowering time to boost grain protein content. The purpose of this study is to determine if the grain protein boost provided by late N application is affected by method of application. A trial testing late season N application methods was conducted at the Maricopa Ag Center in the 2016 growing season. The crop was grown 211 lb N/acre in split applications until flowering when 35 lb N/acre was applied as UAN32 in the irrigation water (fertigation), as low biuret urea in a foliar application, or as urea granules compared to no N application at all at flowering. In this study, we were not able to detect a difference in grain protein or any other variable measured due to the late N application method. We did measure a 0.4% increase in grain protein regardless of late season N application method compared to the control with no late N applied.