The study looked at how different types of rice plants respond to different amounts of potassium fertilizer. They found that increasing potassium application led to higher rice yield and harvest index, with the best results seen at a rate of 12 kg/667m2. Potassium application also increased the amount of potassium absorbed by the plants and changed where the potassium was distributed within the plant. However, as the potassium application rates increased, the efficiency of potassium use by the plants decreased. Conventional japonica rice varieties performed better in terms of yield and potassium absorption compared to hybrid japonica varieties.