Assessment of genetic purity in rice (Oryza sativa L.) hybrids using microsatellite markers

The objective of the present study is to detect genetic impurity in the seed lots of CMS lines, restorers and hybrids and to identify signature markers to differentiate parents and hybrids through DNA-based assays. Furthermore, attempts have been made to find out an alternative to Grow-Out-Test, which is very tedious, time consuming and used conventionally for seed genetic purity testing since beginning of quality seed multiplication chain. Fifty-one rice-specific sequence tagged microsatellite (STMS) primer pairs distributed throughout the rice genome were employed for fingerprinting of eight rice hybrids and their parental lines with a view to assess variation within parental lines and to test the genetic purity of the commercial seed lots. Among those, 51 markers, 28 microsatellite markers showed polymorphism (54.90 %). A total of 98 alleles were obtained with an average of 1.92 alleles per primer pair and number of alleles amplified for each primer pair ranged from 1 to 4. A set of markers were identified to differentiate parental lines of the hybrids and which emphasizes the immense scope of those molecular markers for their use in the unambiguous identification of hybrid, which would be of great benefit to farmers that depend on the hybrids.