Relations Among Indica-Japonica Extent and Combining Ability and Heterosis in Two-Line Hybrid Rice

To increase the predication of utilization of heterosis between indic and japonica rice subspecies in two line hybrid rice,the relations among indica japonica extent and combining ability and heterosis were studied by using 4 photo thermo sensitive genetic male sterile lines and 11 excellent male parental lines. The results show that the correlations among the indica japonica extent of parental lines and heterosis over male parent and specific combining ability effect are significant,while the indica japonica extent of parental lines and heterosis over male parent are correlated insignificantly with general combining ability .