Cytogenetics of Induced Semisterile Mutants of Rice Variety Taiohung (Native) 1

Gamma-ray induced semi-sterile mutants of an indica rice variety T(N)1 were studied for their genetic and cytological behaviour. All the semi-sterile lines exhibited either a mono-hybrid or dihybrid segregation ratio and the semisterility behaved as a dominant trait. The meiotic behaviour of all the lines including the F₁ hybrids between the parent variety and fertility derivatives was by and large normal except for stray anomalies. It is suggested that the sterility in the present case is genie and is governed by a series of duplicate dominant genes regulated by an inhibitor-anti-inhibitor genetic system.