Genetic Variability Evaluation Among Iraqi Rice (Oryza sativa L) Varieties using RAPD Markers and Protein Profiling

Genetic variability and relationships among ten rice varieties were studied by using 20 decamer random primers and SDSPAGE methods. Out of 22, 20 Random Amplified Polymorphic DNA (RAPD) primers revealed polymorphism, while the remaining 2 primers showed no reaction. The primers produced a total of 109 bands, of which 62 (56.88%) were polymorphic. The number of polymorphic fragments for each primer varied from 1 to 9 with an average of 3.1 polymorphic fragments. The primer OPC-07 produced the maximum number of polymorphic bands. The RAPD data were analyzed to determine the genetic distance coefficients which ranged from 0.30 to 0.76. Cluster analysis was performed using the Jaccard’s coefficient. The dendrogram resolved the selected rice varieties into four major clusters. On the other hand, similar varieties of rice were analyzed for endosperm storage proteins by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) to estimate their genetic diversity. Seed storage profiling led to the detection of a total of 12 polypeptide bands. The molecular weights of peptides ranged from 284 to 11 kDa. Polymorphism was not evident in all seed proteins of diverse molecular weights among all rice varieties, but two polymorphic bands (63 and 120 kDa) were found in a high molecular weight region. The results of the genetic diversity, obtained during this study, will be useful for the selection of the parents for developing rice breeding varieties in the future.