Wild barley varieties were studied to find those with high nitrogen use efficiency. The researchers looked at how different genotypes absorbed and used nitrogen during growth with low nitrogen levels. They found that the biggest differences in biomass, nitrogen content, and nitrogen use efficiency were seen at the heading stage. Varieties with high nitrogen utilization efficiency had more biomass and grain yield compared to those with low efficiency. The study showed a strong correlation between biomass and grain yield at the maturing stage. Overall, wild barley with high nitrogen use efficiency genotypes performed better in terms of biomass and grain yield.