Nutrition for Hyper Yielding Wheat cv Stockade

• Following six years of pasture legume 2014-19 (Fescue/Lucerne/Clover), and three years of cropping (canola 2020, grazing wheat 2021 and canola 2022), there was no significant yield response to applied nitrogen (80-280kg N/ha), although there was a trend for higher yield up to 160kg N/ha.
• With 226kg N/ha in the soil 0 – 60cm on 10 July the zero N treatment (only 12kg N/ha MAP applied) yielded 8.08t/ha with a protein of 9.5% indicating the presence of 154kg N/ha in grain at harvest.
• If 75% of the N is assumed to be in the grain, and 25% in the straw residue, then the total N uptake at harvest in zero N plots would be 169kg N/ha indicating approximately 57kg N/ha left over from what was measured at sowing, assuming no losses.
• All N applications applied as 2 or 3 split urea applications only served to increase protein, but the yield increases evident up to 160kg N/ha were not statistically significant.
• Applying N as a three split at 200 N gave a yield increase which in 2022 was also associated with lower lodging pressure than the equivalent two split approach, but the yield difference in both years was not significant.
• Applying manure or the equivalent macro nutrients carried in the manure on top of 120N gave no significant yield benefit, but the manure treatment did confer higher biomass at flowering than the equivalent inorganic fertiliser treatment.
• There were no significant differences in harvest dry matter as a result of N application.
• The zero N treatment had the highest test weight and lowest screening as was the case in 2022.