Sum15-18 Nitrogen and Potassium in Noodle Wheat Varieties, Binnu


To investigate the effect of nitrogen and potassium on yield and grain quality of noodle wheat varieties in the northern agricultural region.

For further details contact your local Area Manager or the Summit Research Team

Table 1: Soil Analysis
Fig 1: Yield and Protein
Fig 2: Yield response curves


  • Calingiri is a consistent performer across various fertilizer rates, however the new varieties Supreme and Zen show potential to better utilise K and N fertilizer to improve yield and returns.
  • Yields ranged from 1.5 t/ha in Supreme with nil K and N 5 kg/ha applied, to 3.4 t/ha in Zen with K 25 and N 75 kg/ha applied.
    Response to K would be expected on a soil with Colwell K of 30 mg/kg at the surface and lower at depth.
  • Varieties responded differently to nutrient rates. Generally, application of K increased yield of noodle wheats and the response was significant for both Supreme and Zen, but not for Calingiri.
  • Zen showed the greatest potential for top-end yield and had the greatest relative yield response to K application.
  • Supreme had the lowest yield at low K and N rates but showed the greatest relative yield response to N application.
  • Calingiri performed better than both Supreme and Zen at low K and N but was much less responsive to both K and N application.
  • Neither K or N affected grain protein content.
  • Supreme consistently showed lower protein (9.9-10.4%) than both Calingiri and Zen (10.8-11.2%). However, all three varieties were within the quality specifications to achieve ANW1 grade.
  • Gross margins net of cost of fertiliser applied weigh strongly in favour of K application and increasedN in the new noodle wheat varieties Supreme and Zen, and much less-so in Calingiri.