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Genetic improvement Is one of the most effective strategies to prevent rlce from blast and bacterial blight (BB)diseases,the two most prevalent diseases jeopardizing rice production.Rice hybrids with dural resistance to blast and BB are needed for sustainable production of food.An incomplete diallels design resulted in 25 crosses between five blast and five BB resistant germplasrn accesslons.Only one pair of parents,DH146 × TM487,showed polymorphism for all the markers to Identify one blast resistance gene P125 and three BB resistance genes,Xa21,xa13 and xa5,thus it was used in the marker-assisted selection (MAS).F2 individuals of DH148 × TM487 were genotyped using flanking markers of RM3330and sequence tagged site (STS) marker SAT for P125.The resistant F2 plants with P125 were used for pyramiding BB resistance genes Xa21,xa13 and xa5 identified by the markers pTA248,RM264 and RM153,respectively In subsequent generations.Finally,after selection for agronomic traits and restoration ability among 12 pyramided lines,we acquired an elite restorer line,R8012 including all four target genes (P125+Xa21+xa13+xa5).Hybrid Zhong 9A/R8012 derived from the selected line showed stronger resistance to blast and BB,and higher grain yield than the commercial checks uniformally in experimental plots,2007 state-wide yield trial and 2008 nation-wide yield trial.This study provides a paradigmatic example to show that MAS is a practically feasible tool in effectively pyramiding multiple resistance genes.The resultant restoring line and its hybrid would play an important role in securing rice production in China.