This study induced phenotypic diversity in bread wheat (Triticum aestivum L.) using gamma rays, EMS (ethyl methane sulfonate), and their combined application to improve grain yield and end-use quality. Healthy seeds of three well-adapted cultivars received treatments with the mutagens and advanced through four generations with standard agronomic practices. The M₁ and M₂ generations exhibited reduced germination, stunted growth, and altered spike morphology, confirming the effectiveness of mutagenic treatments. Based on phenotypic evaluation, the selection of 30 promising mutant lines ensued in the M₃ generation for detailed characterization. Among these, mutant line SE4/12-1 exhibited the shortest plant height, SG2/12-26 had the highest numbers of tillers per plant, and SE5/12-7 showed the longest spike length. Mutant lines SG4/12-35 and SE2/12-29 appeared with the highest number of spikelets per spike, whereas SE5/12-15 produced the highest number of grains per head spike. SE5/12-13 recorded the maximum head spike yield. Considerable variation was also evident in grain quality traits, with grain hardness index, seed diameter, moisture content, and gluten content. The highest Zeleny sedimentation value (87.3 ml) resulted in the mutant line SG2/12-27, and the mutant line SE4/12-5 displayed the highest falling number (729 sec). Overall, the selected mutant lines provide valuable genetic resources for breeding high-yielding wheat varieties with improved grain and processing quality.

Keywords: Bread wheat (T. aestivum L.), gamma rays, ethyl methane sulfonate, ideotypes, grain texture, falling numbers, gluten content, Zeleny sedimentation value

Key findings: Gamma rays, EMS, and their combined treatments generated substantial phenotypic diversity for the development of new ideotypes in bread wheat (T. aestivum L.). Promising wheat lines showed desirable agronomic traits, and these useful genetic resources can be beneficial in developing high-yielding wheat cultivars with improved quality.