Nitrogen and phosphorus fertiliser requirements of irrigated wheat at Emerald, Queensland

Abstract

N and P fertilizer requirements of irrigated wheat cv. Oxley or Kite were studied on 3 soil types at Emerald in 1975-76. The optimum rates of fertiliser application were found to be 100 kg N/ha and 25 kg P/ha for a yield goal
of 4500 kg/ha and 150 kg N/ha and 25 kg P/ha for a yield goal of 6000 kg/ha. At high yield levels, the low
values for available nitrogen and phosphorus in the soil prior to planting were found to be of little importance
in the determination of the optimum rates of nitrogen and phosphorus fertiliser application.