The study looked at how different amounts of nitrogen fertilizer affect the yield and insect infestation of four rice cultivars. They found that using 69 kg of nitrogen per feddan is better than using 92 kg, as it gives similar yields without increasing insect infestation. The Egyptian Hybrid 1 cultivar had the highest yield, while Sakha 101 had the best grain weight and harvest index. It's important not to use too much nitrogen fertilizer, as it can attract harmful insects like the rice stem borer and leaf miner.