In vitro breeding for salt-tolerance rice Ⅳ. Genetic analysis for proline content in progeny of F₂generation in relation to salt-tolerance

Proline content in the F₂ seed-derived callus grown on salt medium was analyzed to know the mode of segregation and genetic analysis in the F₂ generations. Linkage analysis implied that at least six linkage groups were involved in proline accumulation related to salt-tolerance. The segregation of proline accumulation in the progeny of Gihobyo/Annapurna F₂ generation was bimodal. The well-fitted segregation ratio of 15:1(low:high) indicated that two genes were involved and they were complementary. Proline content in the progeny of Annapurna/Nagdongbyo F₂ generation showed normal distribution, which suggested many genes might be concerned in this cross combination.