The study looked at how different types of rice respond to different amounts of nitrogen fertilizer. They tested five rice varieties with three levels of nitrogen in South China. The results showed that using 187.5 kg of nitrogen per hectare led to the highest leaf area, growth rate, and total weight of the rice plants. This resulted in a significant increase in grain yield compared to using no nitrogen or 225 kg per hectare. The variety Fengmeizhan and Yuxiangyouzhan had the highest yields. Early rice had a slightly higher yield than late rice. Overall, using 187.5 kg of nitrogen per hectare gave the best results in terms of yield and efficiency.