The present research aimed to assess the pivotal role of gamma (γ-ray) and fast neutron (FN) radiations in developing rice (Oryza sativa L.) mutant types resistant to salinity (NaCl) and drought stress conditions. Local rice cultivars irradiated with different levels of ionizing radiation had their seeds subjected to salinity and drought stress conditions. Rice cultivars showed varied responses to ionizing radiation and stress factors for morphological and yield-related traits. The highest number of mutant forms resulted from the local rice cultivar Syr Suluy, followed by two other cultivars, viz., Leader and Aikerim. The resulting M1 genotypes significantly differed from the parental forms for morphological and yield-related parameters, i.e., plant height, panicle length, grain size, and grain weight. This genetic material can be effective in the development of synthetic cultivars adapted to the soil and climate stress conditions of the Aral Sea area in Kazakhstan.

Keywords: Rice (O. sativa L.), cultivars, mutation, gamma rays, fast neutrons, salinity and drought stress conditions, morphological and yield-related traits

Key findings: Determining the average lethal irradiation doses was successful for the local rice (O. sativa L.) cultivars that had been bred for the specific environmental conditions of Kazakhstan, as well as establishing their salinity and drought treatment levels. Rice cultivar Aikerim showed a higher productivity than the control. The fast neutron-irradiated seeds produced more surviving rice plants with higher productivity than γ-rays.