Recently, application of physical modification techniques such as radiation of gamma rays could improve the performance of wheat plants through development of new products. Radiation restricted by intensity and duration of exposed to gamma irradiation. Two field experiments were carried out in the demonstration farm of Agricultural Research station, Elgemmeiza, Gharbia governorate, Egypt during 2020/2021&2021/2022 seasons with the aim of the performance of five bread wheat genotypes namely (NING MAI 50- 0CHN, SAKHA 93, GIZA 168, SIDS 12, SKAUZ) exposed to five doses of Gamma rays i.e. (5, 10, 15, 20 and 25 Kr) plus control without irradiation on bread wheat growth, yield, yield components, seedling parameters and rust diseases. Results showed that wheat genotypes significantly differed in seedling parameters, and yield components in both seasons. SKAUZ genotype surpassed other genotypes in germination percentage and grain yield while NING MAI 50 gave longest seedling and seedling vigor index 1 on the other hand Sakha 93 gave high seedling dry weight and seedling vigor index 2 with high resistance to yellow rust but Giza 168 gave the highest leaf rust resistance with increase doses of Gamma rays in both seasons. Gamma rays among 5 to 15 kr caused improvement in seedling parameters and yield attributes. Doses between 5 to 25 kr were the most beneficial for rust resistance in comparing to control. Results exhibited that the interaction effect between wheat genotypes and gamma rays was significant on all studied traits in both seasons.
