Improving BPH Resistance Of Key Sterile And Restorer Lines In Rice Through Molecular Marker-Assisted Selection

Brown planthopper(BPH)is a kind of serious pest in rice production,which could reduce yield,damage rice quality and affect the commercial value of rice,seriously.Moreover,utilization of modern biotechnology combined with traditional breeding methods to select two-line male sterile lines and restorer lines which could be resistant to BPH by themselves is one of the most effective ways.In this study,BPH resistance genes Bph14,Bph15,Bph18(t)、Bph20(t)and Bph21(t)were introduced into C815 S,Chuang5S,R4418 and Hua Zhan,which were widely parent materials used in two-line hybrid rice production by cross,backcross and molecular marker-assisted selection(MAS)in order to improve the resistance of them.The main test results are as follows:1.Carrying Bph14 and Bph15 genes,two C815 S improved two-line male sterile lines,two Chuang5 S improved two-line male sterile lines,and one R4418 improved restorer line were developed.Carrying Bph18(t)gene,one C815 S improved two-line male sterile line,two Chuang 5S improved two-line male sterile lines,two R4418 improved restorer lines,and two Hua Zhan improved restorer lines were developed.Carrying Bph20(t)and Bph21(t)genes,one C815 S improved two-line male sterile lines,one ChuangS5 improved two-line male sterile lines,and two R4418 improved restorer lines were developed.2.The BPH resistance identification results indicated that 4 receptor parents,C815 S,Chuang5S,R4418 and Hua Zhan,were all susceptible,3 donor parents,B5,IR65482 and IR71033,were all high resistant,while the improved steriles,7CS04,7CS05,7CS09,7CS06,7CS14 and 7CS10 were resistant,7CS07,7CS13,7CS18 and 7CS27 were middle resistant;the improved restorers,7CR04,7CR05,7CR10,7CR24 and 7CR28 were resistant,7CR11 and 7CR15 were middle resistant to BPH.3.The agronomic traits results showed that the improved steriler lines had no significant differences with the receptor parents in terms of plant height,panicle number,flag leaf length,flag leaf width,flag leaf angle,and stigma exsertion rate,while,they were better than the receptor parent in terms of total spikelets per panicle and spike length;The improved restorer lines had no significant differences with the receptor parents in terms of plant height,flag leaf length,flag leaf width,seed setting rate,and 1000-grain weight,while,they were batter than the receptor parents in terms number of panicles and panicle length.