Effect of pasture on subsequent wheat crops on a black earth soil of the Darling Downs. Ill. Comparison of nitrogen from pasture and fertiliser sources

Abstract

In the last two years of an eleven year pasture-wheat rotation experiment, 1967 and 1968, all plots growing wheat were split to permit the application of four rates of nitrogen fertiliser as urea. A comparison was made between the nil fertiliser sub-plots of the rotation treatments and the fertilised sub-plots of the continuous wheat treatment. It was shown that the application of nitrogen fertiliser was unable to nullify differences due to previous pasture, in grain yield, dry matter production, grain protein per cent and grain N uptake. The inefficiency of fertiliser nitrogen compared to pasture nitrogen was attributed to a better profile distribution of pasture nitrogen.