The researchers studied different barley lines in three environments to see which traits are most important for improving barley crops. They looked at things like days to maturity, plant height, grain yield, and more. They found that traits like grain yield per plant and number of grains per spike are the most important for improving barley. These traits have high variability and can be passed down from one generation to the next. So, focusing on these traits can help make better barley crops in the future.