To measure and demonstrate on-farm strategies to reduce nitrous oxide emissions and improve nitrogen use efficiency.

In general, across the three seasons (2014–16), N2O emissions from fertiliser applications were slightly elevated compared with the control. In some seasons however, N2O emissions were increased above background levels and cumulative values were at the higher end of those reported from dryland farming (>2kg or 2000g N2O-N/ha/ season). High emissions were measured from both IBS and first node (GS31) application timings, depending on the seasonal conditions. Seasons dominated by early heavy rainfall favoured in-season nitrogen application for reduced N2O emissions. However, these treatments often did not result in the highest grain yield or quality. It is important to note that cumulative emissions were only assessed over the growing season to look at in-season fertiliser nitrogen management. Annual values may have been higher if summer fallow emissions were also assessed prior to sowing.