The researchers studied how different amounts of water and nitrogen fertilizer affect the growth and yield of five types of bread wheat. They found that withholding water at certain stages increased the amount of nutrients transferred to the grains, but applying nitrogen at a specific stage reduced this transfer. Overall, less water led to lower grain yield, but adding nitrogen helped increase it. The type of wheat called Mihan had the highest yield when given water and nitrogen at specific times. Choosing wheat varieties that can move nutrients effectively during droughts could help create high-yielding crops in dry conditions.