Pyramiding of blast and bacterial blight resistance genes in premium quality rice variety, BRRI dhan63 through marker-assisted breeding approach

Rice blast and bacterial blight diseases are the global threat for rice production. To develop blast and bacterial blight resistant lines, two blast resistance genes (Pi9 and Pb1) and three bacterial blight resistance genes (xa5, xa13 and Xa21) were pyramided in the background of premium quality rice variety BRRI dhan63 through marker-assisted backcross breeding. Pi9-US2, Pb1-US2 were used as donor parents for Pi9 and Pb1, respectively and for xa5, xa13 and Xa21, IRBB60 was used as a donor parent. Three crosses were made to pyramid these genes in BRRI dhan63. F₁ to BC₃F₆ population was developed by continuous backcrossing, selfing and foreground selection. Segregation analysis (chi-square test) of genotypic and phenotypic data of 400 BC₃F₂ population revealed that the inheritance…