The nitrification inhibitor 3,4-dimethylpyrazole phosphate decreases leaf nitrate content in lettuce while maintaining yield and N2O emissions in the Savanna of Bogotá

Abstract

The use of nitrogen (N) fertilizers in crops increases their yield but can modify their quality and lead to environmental problems by the emission of greenhouse gases (GHG). One of the strategies for mitigating this emission is the use of nitrification inhibitors (NI) as 3,4-dimethylpyrazole phosphate (DMPP). Additionally, the increased persistence of N after the application of NI can reduce the amount of fertilizer applied. A field experiment with lettuce was conducted in the Savanna of Bogotá. N was applied as ammonium sulphate nitrate (ASN 26%) at a rate of 70 kg N/ha and as the combination of ASN with DMPP (ENTEC® 26) at 50 and 70 kg N/ha rates. GHG emissions, soil parameters, lettuce yield, its components, N, nitrate and mineral elements contents were measured. With high soil nitrate contents, a standard dose of N fertilizer with DMPP maintained the yield and N content of lettuce, while it had no effect on GHG emissions. A reduction of 20 kg N/ha using DMPP was able to keep the yield meanwhile improving the quality of the crop due to a lower nitrate accumulation in lettuce leaves.

Keywords

• ch4 emissions
• co2 emissions
• n2o emission factor
• nitrogen content
• yield-scaled n2o emissions