Efficacy of aucubin as a nitrification inhibitor assessed in two Canterbury field trials

Abstract

ABSTRACTRuminant urine patches are nitrous oxide (N2O) emission hot-spots and compounds that inhibit nitrification in urine-affected soils, a key step in soil N2O production, can significantly reduce N2O emissions. Aucubin, a potential nitrification inhibitor found in plantain (Plantago lanceolata) was assessed in two field trials for its efficacy in reducing urine patch nitrate (NO3−) accumulation and N2O emissions. Plantain leaf extract or commercially derived pure aucubin was added to urine, alongside a control and urine only treatment, and applied to standard gas chambers and monitored for 35 days. While there were some daily differences between treatment soil nitrogen and N2O emissions, there were no overall significant differences between cumulative N2O emissions. Aucubin, applied as a one-off dose, seems to act as a nitrification inhibitor for a short period after application onto soil, but it’s inhibitory effects are not sufficient to produce significant reductions in overall urine patch N2O emissions.