Inheritance of fertility restoration of five sources of cytoplasmic male sterility in rice (Oryza sativa L.)

摘要

The cross combinations involving six male sterile lines of five different cytoplasmic sterile sources, i.e. IR 58025 A and PMS 2 A (WA), IR 68885 A (Mutant-induced by gamma irradiation of IR 62829 B), IR 54755 A (ARC), G 46 A (Gambiaca) and D 297 A (Dissi), when crossed with five common restorers, namely Ratnagiri 3, Swarna, IR 5, IR46 and IR 54, showed more than 80% spikelet fertility restoration in all the combinations except IR 54755 A x Swarna and IR 54755 A x IR 54. The F2 segregation classification based on pollen and spikelet fertility in the 28 cross combinations, indicated the presence of 2 independent dominant fertility-restoring genes. The mode of action of the 2 genes varied in different crosses revealing 3 types of interaction, namely epistasis with dominance, epistasis with incomplete dominance and epistasis with recessive. The change in fertility restoration by the same restorer with CMS line of the same source and different source could be due to the influence of female parent genotype or fertility restoring genes has different penetrance and is affected by the modifier.