Agronomic improvements through the genetic and physiological regulation of nitrogen uptake in wheat (Triticum aestivum L.)

Nitrogen (N) uptake is the first step in nitrate assimilation, and efficient N uptake is essential for plant growth, especially for protein biosynthesis and photosynthetic activities. In cereals, improved N uptake is closely coupled with an increase in nitrogen use efficiency (NUE) and yield improvements. Because wheat (Triticum aestivum L.) is a leading crop worldwide, a better understanding of N uptake regulation in wheat is vital to improving NUE and developing sustainable agricultural systems. However, detailed information regarding the biological mechanisms that are responsible for the more efficient uptake of ambient N by wheat is limited. This review presents recent developments in the biological mechanisms of N uptake in wheat, including plant growth regulations, fundamental roles of root systems, interactions between N species, and genetic controls. Specifically, this paper provides a number of potential strategies that can be used to increase wheat N uptake. The information provided here may guide N fertilizer management during wheat production and further elucidate the plant regulatory mechanisms that are involved in N uptake, which can thereby increase wheat NUE.