Impact of Urease and Nitrification Inhibitors on the Most Economic Rate of Nitrogen for Corn at Both Preplant and Side-Dress Application Timing

Lead Applicant: John Lauzon

Research Priority: Sustainable Production Systems

Program Type: Tier 1

Funding Cycle: 2026/2027

Research Centre: Ontario Crops Research Centre - Elora, Ridgetown, Winchester

Research Summary: Current research at the University of Guelph and Agriculture and Agri-Food Canada shows ureas and nitrification inhibitors may reduce nitrogen losses. However, while inhibitors lower nitrogen loss, they do not improve yield potential; yields remain constant but require less nitrogen. Despite this, practice often involves using inhibitors without adjusting nitrogen rates. Identifying inhibitors tailored to the most economically efficient nitrogen application rate may further lower environmental losses and boost growers' economic returns. This research aims to address these gaps, improving Ontario corn growers' income and reducing environmental impact.