Facility and experimental design

In 2018 at program end, the Horsham AGFACE facility consisted of four CO2 enrichment rings of 16 m diameter each, and six control plots receiving ambient CO2. Elevated CO2 was targeted at 550 ppm.

Sub-plots with two cultivars and a range of nitrogen input levels and types were randomly distributed within the rings. The intent was to use nitrogen fertiliser at various rates, timing and modes to reduce or reverse the decline in grain protein that is universal under elevated CO2.