Nitrification Inhibitor Value in Irrigated Corn: Insights from a Long-Term Study.

Proper nitrogen (N) nutrition is key to optimizing corn yields. Due to its dynamic behavior in soils, N can be lost through different pathways and negatively impact corn production. Nitrification inhibitors (NI) decrease the rate of ammonium transformation to nitrate in the soil, potentially decreasing denitrification and leaching potential. However, NI only has a positive effect on yield if environmental conditions are conducive to loss to the point of N becoming limiting to crop performance. The objectives of this study were to (i) evaluate the long-term effect of NI nitrapyrin on irrigated corn grain yields and (ii) long-term nitrapyrin return on investment.