Genetic variability in cytoplasmic male sterile lines in rice (Oryza sativa L.)

Diversification of cytoplasmic male sterile (CMS) lines in hybrid rice technology contribute a pivotal role towards the development of superior hybrids. A study was conducted on fifteen elite CMS lines of diverse source of origin to estimate nature and magnitude of genetic divergence and correlation analysis of different agro-morphic traits. Out of fifteen CMS lines, six (6) CMS lines namely IR 58025A, IR 79156A, IR 80559A, IR 68897A, DRR 5A and Pusa 6A exhibited complete pollen sterility (100 %). Based on eight characters, the genotypes were grouped into five (5) clusters at 74% similarities coefficient. The genetic distances between the few CMS lines showed some correlation with geographic origin. In some case, the correlation between the genotypes not suggested the same trend which might be due to genetic drift. The CMS lines having the characters in the genetically distant cluster could, therefore, offer an important role in the development of hybrid rice varieties.