The Effect of EMS (Ethyl Methane Sulphonate) Mutagen on the Qualitative Characteristics of Rice (Oryza sativa L.) Varieties IR 64 and Inpari 32

The use of superior varieties is an important factor in increasing rice productivity and production. Several rice superior varieties are still widely used by rice farmers, including IR 64 and Inpari 32, but each variety has shortcomings. One way to improve the genetics and characteristics of superior varieties is through mutation breeding. Ethyl methane sulfonate (EMS) is a chemical mutagen that can be used to induce mutations. Mutation induction in plants can cause changes in both qualitative and quantitative characteristics. This study was conducted to determine the effect of EMS on the qualitative characteristics of rice plants varieties IR 64 and Inpari 32. The study was conducted at the Gauze House of the Agriculture Faculty, Universitas Sumatra Utara, November 2023-March 2024. EMS was given during seeds soaking. This study used a factorial Randomized Block Design (RBD), with two treatment factors namely rice varieties (IR 64, Inpari 32) and EMS concentration (0%, 1.5%, 2%, 2.5%, 3%.), and three replications. Planting rice seedlings 11 days old was carried out in plastic tubs as many as two rice seedlings per tub, namely seedlings that had a normal appearance, good growth and vigor. Observation variables consisted of culm habit, leaf sheath colour, leaf collar colour, auricle colour and ligule shape. The results of this study showed that application of EMS mutagens to IR 64 and Inpari 32 rice seeds caused variations in the qualitative characters namely culm habit, auricle colour and ligule shape, while leaf sheath colour and leaf collar colour were relatively uniform.