The study looked at how different ways of growing tobacco plants affect the quality of the leaves. They found that the amount of protein, sugar, and starch in the leaves influenced the yield of tobacco. Lower nicotine and higher sugar levels led to better prices. The timing of planting affected the amount of chloride in the leaves. Nitrogen fertilizer affected the potassium levels. Overall, adjusting the amount of nitrogen fertilizer can improve both the yield and quality of tobacco plants.