For milling wheat, achieving the required grain protein can be the difference between achieving a premium price or being down graded to the feed price on the open market. This update discusses the impact of applied nitrogen timing and rates on milling wheat yield, protein and profitability.
Key points
- Nitrogen (N) is important for grain yield and protein content.
- In a 2018-19 irrigated nitrogen trial using cultivars Reliance (premium) and Discovery (medium), the maximum biological yield was around 350 kg total N/ha.
- The economic optimum was between 300 – 350 kg total N/ha.
- The economic optimum was the point where protein specifications were met for both cultivars.
- While protein increased with increasing N rates, it was not profitable to apply more than the economic optimum.
- Unless the N applications have been adjusted earlier in the season, late N at GS 55-59 is still needed to achieve protein specifications.