Lethal dose 50 and the first-generation mutant of upland purple rice cultivar Med Fai 62

Abstract

Inducing mutations is a breeding tool that creates genetic variability. In this study of inducing mutations in the Indica upland purple rice cultivar Med Fai 62 with mutagenic Ethyl Methane Sulfonate (EMS), a completely randomized experimental design was used with four treatments (0, 0.5, 1.0, and 1.5%) and five replications to find an appropriate EMS dose. Analysis of variance of treatments for germination rate showed highly significant differences (P < 0.01). Trend comparisons, and seeking 50% germination (Lethal Dose 50), showed that a 0.2% concentration of EMS was suitable for Med Fai 62 cultivar. Thus, mutations were induced in 5,000 seeds by infusion of 0.2% EMS. After planting for 15 days, 43.74% germination was found. The agricultural traits of the mutated plants were better in several cases than those of Med Fai 62 cultivar, for example in days to flowering, days to maturity, flag leaf length and width, plant height, and 1,000 grain weight. These traits could be useful for the future upland rice breeding programs.

Keywords

• ethyl methane sulfonate
• lethal dose
• mutant
• upland rice