The study looked at how nitrogen fertilizer and planting density affect the yield of a type of early rice called Zhongzao 22. They found that the amount of nitrogen used and the density at which the rice is planted both play a big role in determining the yield. Increasing nitrogen levels generally led to higher yields, but too much nitrogen could decrease the number of seeds produced. Lowering planting density with higher nitrogen levels can actually improve yield. The best combination for high yield was found to be 195 kg/ha of nitrogen and 30×104 hill/ha planting density.