Late-season nitrogen may be efficient way to increase winter wheat protein

On-farm experiments were conducted throughout California to study the effect of early- and late-season nitrogen fertilizer applications on grain protein in winter wheat. Results indicate that early-season nitrogen application is inefficient. However, late-season nitrogen (N) applications coupled with irrigation can lead to efficient fertilizer N uptake and partitioning to grain, and increased grain protein. Late-season application was not efficiently recovered in the grain when there was midseason nitrogen application or high native soil nitrogen supply.