The new nitrification inhibitor DMPP (ENTEC®) — Comparisons with DCD in model studies and field applications

Abstract

DMPP (3,4-dimethylpyrazole phosphate (ENTEC®) is a new nitrification inhibitor (NI), the use of which is likely to advantage the environment and farmers. Comparisons with DCD (dicyandiamide) show that more than an order of magnitude less DMPP than DCD is needed to inhibit nitrification. Further features of DMPP are a soil — specific longer time period of efficacy and a substantial higher plant compatibility than DCD. Due to sorption DMPP is less mobile than DCD in soils and inhibits nitrification in the top soil even after simulation of heavy rainfall. Hence, NO₃⁻ leaching is more efficiently restricted by DMPP than by DCD under leaching conditions. Field experiments indicate reduced N losses due to N₂O volatilisation after DMPP or DCD application and no increase of NH₃ volatilisation from ammonium containing fertilisers stabilised with DMPP.