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.