EMS-induced variability in phytochemical and antioxidant traits of Withania somnifera varieties (NMITLI-118 and CIM-Pushti) across the generation.

Abstract

Withania somnifera is an important medicinal plant in which induced mutagenesis can generate biochemical variability. This study evaluated the effects of ethyl methane sulfonate (EMS) on two cultivars, NM-118 and CIM-Pushti, using five EMS doses (0.2-1.0%) and a control. EMS treatment was associated with variation in chlorophyll pigments, carotenoids, total phenolic and flavonoid contents, total antioxidant capacity, reducing power, DPPH· scavenging activity, and protein content. Moderate EMS doses (0.4-0.8%) generally increased pigment accumulation and several biochemical traits, whereas higher doses reduced pigment content. DPPH· scavenging activity generally decreased with increasing EMS dose, while other biochemical responses varied with dose, cultivar, tissue, and generation. CIM-Pushti exhibited greater variation in several parameters than NM-118. Differences between M₁ and M₂ indicated generation-dependent responses. Overall, EMS treatment was associated with measurable biochemical variability, providing a preliminary screening of EMS-associated responses.