Method for improving indica-japonica hybrid maturing rate of rice

The invention discloses a method for improving the indica-japonica hybrid maturing rate of rice, and belongs to the field of rice breeding. The method comprises the following steps: (1) selecting an indica type two-line sterile line gramine-15S and a japonica rice material R2007 to hybridize, and carrying out shuttle breeding in two places, namely Hainan and Hunan, so as to obtain four sterile lines, namely sterile lines 38S, 38-1S, 38-2S and 38-3S with indica-japonica blood lineage; (2) hybridizing R2007 serving as a male parent with an indica rice restoring line R1002, performing shuttle breeding and systematic selection in Hunan and Hainan, hybridizing intermediate lines of different generations with four sterile lines in the selection process respectively, and performing systematic breeding on materials with high hybridization maturing rates to obtain a restoring line R2097 of which the hybridization maturing rates with the four sterile lines are all higher than 75%; and (3) hybridizing the R2097 with the