The researchers studied how different amounts of water and nitrogen affected the growth and yield of winter wheat. They found that giving the wheat 450 cubic meters of water and 180 kilograms of nitrogen per hectare led to the highest dry matter and nitrogen accumulation, as well as the best grain yield. This combination also improved water and nitrogen use efficiency, increased photosynthesis in the wheat leaves, and produced more carbohydrates, resulting in a higher grain yield of 9400 kilograms per hectare.