Winter wheat responses to enhanced efficiency granular nitrogen fertilizer in the Canadian Prairies

Optimizing the timing of nitrogen (N) enhanced efficiency fertilizers (EEFs) may maximize winter wheat ( Triticum aestivum L.) grain yield, protein content, and N-use (NUE). From 2013 to 2018, experiments were conducted at two irrigated six rain-fed sites across Canadian Prairies (24 site-years) evaluate responses N source timing/placement effects EEFs. Nitrogen sources included untreated urea, nitrification inhibitor nitrapyrin treated urease N-( n-butyl) thiophosphoric triamide (NBPT) plus dicyandiamide (DCD)-treated urea (NBPT + DCD), polymer-coated (PCU). The all side-banded planting, 30% planting 70% broadcast in-crop late-fall (averaged 38 days after planting; split-applied late-fall), or early-spring 224 early-spring). Nitrous oxide methane emissions measured one site test whether influenced CO 2 -equivalents (CO -eq; nitrous methane). Under irrigation, NBPT DCD consistently produced highest yields regardless timing/placement; however, 80% recommended rate caused suboptimal (≤11%) unless split-application was adopted. Untreated net -eq yield-scaled emissions, with when early-spring. To optimize production NUE, we conclude that all-banded during seeding operations provided similar often superior results other sources, including a more typical system time seeding.