Enhanced N management strategies for winter wheat production in the Canadian Prairies.

To address knowledge gaps around enhanced efficiency urea fertilizer efficacy for nitrogen (N) management, a study was designed to enhance integrated nutrient management systems for western Canadian winter wheat producers. Three factors were included in Experiment 1: 1) urea type (urea, urea+urease inhibitor -Agrotain®; urea+urease and nitrification inhibitor – SuperU®, polymer-coated urea – ESN®, and urea ammonium nitrate - UAN), 2) application method (side-band vs. spring broadcast vs. 50% side-band: 50% spring broadcast), and 3) Cultivar (AC Radiant hard red winter wheat vs. CDC Ptarmigan soft white winter wheat). The Agrotain® and CDC Ptarmigan treatments were removed in Experiment 2 to allow for additional application methods: 1) fall side-band, 2) 50% side-band:50% late fall broadcast, 3) 50% side-band:50% early-spring broadcast, 4) 50% side-band:50% mid-spring broadcast, 5) 50% side-band:50% late-spring broadcast. CDC Ptarmigan produced superior grain yield and nitrogen utilization over AC Radiant. Grain yield and protein content were influenced by N form and application method. Split applications of N usually provided maximum yield and protein, particularly with Agrotain® or SuperU®. Conversely, the UAN and ESN® form, when all broadcast in spring, all side-banded in fall, or with late fall-broadcasting, performed poorly. An exception to the poor fall-application results was the SuperU® treatments, which produced similar yield to the highest-yielding treatments. The results suggest split applications of N may be most efficient for yield and protein optimization when combined with an enhanced efficiency urea product, particularly with urease or urease+nitrification inhibitors, and if the majority of N is applied in spring.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author