Genetics of male Sterility in Rice

A line of rice (G2266) was found to be male sterile, When line G2266 was used as female parent in crosses with normal fertile plants seed development was normal. However, seed development was reduced (11% seed set) in the reciprocal crosses. All F1 hybrids were semisterile. Although meiosis in PMC's in G2266 and the F1 hybrids was regular, the frequency of normally stained pollen grains was low in G2266 (2%). A wide range in stainable pollen (0–100%) was found in the F1 hybrids. Backcrossing the F1 hybrids as pollen parent caused reduction in seed development. The reciprocal back-crosses using the normal parent as pollinator gave rise to higher seed set. Seed set was also reduced in those reciprocal backcrosses which involved G2266 as the pollen parent. Segregation of approximately three fertile semisteriles to one sterile individual occurred in the F2 generation, suggesting that male sterility was due to a recessive gene free of cytoplasmic influence.