Abstract:
Rice cultivars IR6 and IR8 were exposed to different doses of gamma radiation and stable mutants along with parents were studied for genetic diversity on the basis of morphological traits and molecular marker (RAPD). Morphological data showed that mutants of IR6 and IR8 performed well as compared to their parents. The genetic variation was determined through RAPD. A total of 74 scorable bands were observed, out of which 47 (63.6%) were polymorphic and 27 (36.5%) were monomorphic. The size of fragments ranged from 201bp – 3.2 kbp. The number of fragments produced by various primers ranged from 1-12 with an average of 4.93 fragments per primer. Maximum 12 bands were amplified with primer A-03 and minimum one band was amplified with primer A-15, A-19 and B-10. Some specific RAPD bands were also identified reflecting the RAPDs application for the identification of rice cultivars/genotypes. Results revealed that variety Sarshar and IR8-178 contain a specific segment of 451bp amplified with primer A-19. The highest similarity was observed between IR8-15A and IR8-178 (96%) and the least similarity was recorded between IR-8 and IR6-15/B (69%). On the basis of RAPD studies, genotypes were grouped on the basis of their similarities and distinctness.
