Investigating the impact of ethyl methanesulfonate (EMS) on in vitro germination indices of sorghum with Taguchi design

Sorghum (Sorghum bicolor L.) is a major edible cereal and forage crop, cultivated all over the world, and can grow on low-fertility lands. However, the development of new cultivars with desired traits is highly desirable and can be achieved by using chemical mutagens. The seeds were treated with ethyl methane sulfonate (EMS) at the rates of 1.0%, 2.0%, and 3.0%. Surface-sterilized seeds were treated for 2h, 4h, and 6h, followed by culturing the seeds on Murashige and Skoog (MS) medium for germination. Data regarding germination were calculated after 2, 4, 6, and 8 days, followed by analysis using the GerminaR package, with different germination metrics. Data generated using GerminaR was analyzed by analysis of variance (ANOVA) and Taguchi Design (TD) analysis for multifactorial optimization. Results illustrated that seed treatment with.0% EMS for 2 hours enhanced germination performance with low mean germination time (MGT), uncertainty (UNC), germination speed, and synchrony. Whereas application of 3.0% EMS for longer durations negatively impacted germination metrics, indicating stress-induced delays and variability. The results of the TD model highlighted that EMS concentration primarily influences germination percentage (mgp) and synchrony (SYN). Whereas treatment time influenced temporal parameters such as mean germination time (MGT) and germination variance. The study underscores the utility of germination indices and Taguchi optimization in assessing and refining EMS-induced mutagenesis protocols for crop improvement.