The study looked at how water and nitrogen levels affect the chlorophyll content and photosynthesis of spring wheat leaves. They found that the right amount of nitrogen can increase chlorophyll and photosynthesis. High nitrogen levels performed better under drought and good water conditions. As water stress increased, chlorophyll content and photosynthesis also increased. There was a positive link between water use efficiency and photosynthesis, but a negative one with transpiration and stomatal conductance. The relationship between photosynthesis and stomatal conductance and water use efficiency varied depending on the treatment.