Use of DNA polymorphism for characterization and assessment of genetic purity testing in Rice hybrids (Oryza sativa L.)

The investigation for genetic purity testing of hybrids in rice (Oryza sativa L.) using microsatellite markers was conducted on two rice hybrids (DRRH-2 and DRRH-3) and their corresponding parents (IR68897A, DR-714-1-2R, APMS-6A and RPHR-1005) at Seed Research and Technology Centre, Rajendranagar, Hyderabad during wet and dry seasons of 2011. The objective of the study is to identify the signature markers to differentiate parents and hybrids and also to replace grow out test, which has been used conventionally for seed purity testing through DNA based assays. 50 SSR markers were used to screen the cytoplasmic male sterile (CMS) lines, restorers and hybrids. A simple procedure has been standardized utilizing a two dimensional bulked DNA sample strategy involving a 20x20 grow out matrix which was designed for identification of contaminants in the seed lot of CMS lines, restorers and hybrids in 10 days old seedlings.