playNICE

playNICE - Interplay between Biological Nitrification Inhibitors, Nitrogen Cycling, and Agronomic Nitrogen Use Efficiency

Nitrogen (N) fertilization has unintended consequences, many of which we have only recently started to grasp. Poor N use efficiency during crop production, a measure for the amount of N retained in food per amount of N aapplied as fertilizer leads to massive N losses (~40%) to the environment, where it amplifies eutrophication of aquatic ecosystems, and causes changes in atmospheric chemistry and climate. Reducing N loss and increasing N use efficiency is essential to mitigate negative effects of N fertilization.

Currently, synthetic nitrification inhibitors are widely used to reduce detrimental effects of fertilizer N loss from agricultural systems. However, the potential of biological, plant derived nitrification inhibitors (BNIs), naturally inhibiting the conversion of NH3+/NH4+ to more labile NO3- in rhizospheres of crop plants is not yet known.

Why use nitrification inhibitors to reduce fertilizer loss?

The first step of nitrification can be carried out by three groups of microorganisms, the ammonia-oxidizing bacteria and archaea (AOB and AOA), and complete ammonia-oxidizing bacteria (comammox). All three groups of ammonia oxidizers utilize NH3 as their main energy source, a reaction catalyzed by ammonia monooxygenase (AMO) enzymes. Given that AMOs are essential for the activity of all aerobic ammonia oxidizers, possess a wide substrate range, and are responsible for the first step in the process of nitrification, they are an ideal target for inhibition.

The playNICE project aims to

Identify (novel) BNIs naturally secreted as root exudates of common crop plants
Evaluate the efficacy and inhíbition mechanism of BNIs and their degradation products
Determine the effect of BNIs and their degradation products on soil microbe mediated biogeochemical processes in soil (nitrification, denitrification, N fixation), as well as microbial community physiology (C cycling processes)
Determine the mobility, residence time and degradation products of BNIs
Assess the efficacy of BNIs in increasing N retention in soil and N transfer into crops

The playNICE Team

playNICE is a collaborative project of young researchers from the Centre of Microbiology and Environmental Systems Science (University of Vienna) and the Institute of Bioanalytics and Agro-Metabolomics (University of Natural Resources and Life Sciences).