The combination of cytoplasmic male sterility (CMS) in one parent and a restorer gene (Rf) to restore fertility in another are indispensable for the development of hybrid varieties. To genotype rice lines at the restoring fertility (Rf) loci, 38 lines were crossed with a sterile tester (rfrf) line. Pollen fertility test was performed to identify sterile and fertile F1 hybrids. Seven lines were ...