Nitrogen Use Efficiency Field Experimental Data. Hamilton, Victoria, 2012-2013 [Theme 5: Reducing emissions through improved NUE]

This experiment investigates the role that nitrogen use efficiency might play in delivering greater farm profitability and a simultaneous reduction of unnecessary nitrous oxide from high rainfall cropping systems. To achieve this objective a completely randomised block design with ten treatments replicated five times was established on raised beds at Hamilton in south west Victoria. The treatments included a 0N experimental control (0N), four additional rates of N fertiliser (TD10N@Z31, TD35N@Z31, TD85N@Z31 and TD185N@Z31) top-dressed at the first node (Z31) growth stage of wheat growth; a further three treatments involving different timings of N application, all of the N deep banded at sowing (DB100N@Z00), half the N deep banded at sowing and the other half top-dressed at the first node stage (DB50N@Z00_TD50N@Z31), and all of the N top-dressed at first node (TD100N@Z31); a further treatment involving DMPP (3,4-Dimethylpyrazole phosphate, Entec®) coated urea (DMPP85N@Z31) also top-dressed at first node; and finally one deep banded urea (DB85N@Z00) treatment imposed at sowing. Crop biomass, grain yield, grain quality, soil mineral N, soil temperature and soil water and N2O flux have been measured. Static chamber methodology was used to identify relative differences in N2O loss between N fertiliser management.