The Importance of Positive Influences for Gamma Rays in Creating of Novel Drought Stress-Tolerant Rice Mutants across ISSR Markers

Abstract

Given the extreme importance of the rice crop, it is considered a vital source of Egyptian food security, as it provides essential and vital food for the vast majority of Egyptians. Therefore, this study was launched as a serious attempt to genetically improve this strategic crop with the aim of increasing its tolerance to drought stress which has become a major obstacle to rice production under Egyptian
conditions. A range of safe doses of gamma rays were used on Egyptian rice line (GZ1368-S-5-4) to develop new mutants characterized by tolerance to water stress and high yield. The final results were very promising in deriving new 5 M8 rice that reached genetic stability in the eighth generation, as they were superior in yield, tolerant to drought stress and stable in various locations and environmental conditions. All data of yield components and physiological traits measurements indicating tolerance were significantly better under the drought experiment compared to the standard treatment. Further, the water stress tolerance indices test for grain yield/ plant trait showed the superiority of the five rice mutants over the Egyptian parent line mentioned above. Eight ISSR primers were used for analyzing the molecular genetic differences of the six rice lines including the parent line (GZ1368-S-5-4) which
also gave highly polymorphism % reached 100.0% by SR-08, SR-12, SR-13 and SR-21 primers. Further, discovering 35 specific genetic markers for these five promising rice mutants, which will be an important measure for them until they reach and are approved as final rice lines with all the desired attributes mentioned above.