Yield Gain from PI N Applications
Yield gain from PI nitrogen applications
Back when grain yields of 10 t/ha were considered satisfactory, PI nitrogen topdressing was often enough to increase grain yields to 10 t/ha when insufficient nitrogen was supplied from the soil and pre-permanent water fertiliser.
But now we require yields of 12 to 14 t/ha, so extra nitrogen must be applied pre- PW, as nitrogen applications at PI will not increase grain yield enough to compensate for nitrogen deficiency during tillering.
Brian Dunn, NSW Department of Primary Industries, Rice Pre-season 2014