Biological Nitrification Inhibitors with Antagonistic and Synergistic Effects on Growth of Ammonia Oxidisers and Soil Nitrification.

Biological nitrification inhibition (BNI) refers to the plant-mediated process in which nitrification is inhibited through rhizospheric release of diverse metabolites. While it has been assumed that interactive effects of these metabolites shape rhizosphere processes, including BNI, there is scant evidence supporting this claim. Hence, it was a primary objective to assess the interactive effects of selected metabolites, including caffeic acid (CA), vanillic acid (VA), vanillin (VAN), syringic acid (SA), and phenylalanine (PHE), applied as single and combined compounds, against pure cultures of various ammonia-oxidising bacteria (AOB, Nitrosomonas europaea, Nitrosospira multiformis, Nitrosospira tenuis, Nitrosospira briensis) and archaea (AOA, Nitrososphaera viennensis), as well as soil nitrification.

Metabolome fingerprinting reveals the presence of multiple nitrification inhibitors in biomass and root exudates of .

Biological Nitrification Inhibition (BNI) encompasses primarily NH -induced release of secondary metabolites to impede the rhizospheric nitrifying microbes from performing nitrification. The intermediate wheatgrass (Kernza®) is known for exuding several nitrification inhibition traits, but its BNI potential has not yet been identified. We hypothesized Kernza® to evince BNI potential through the presence and release of multiple BNI metabolites.