Introgression Of Pi2 And Pi5 Genes For Blast (Magnaporthe Oryzae) Resistance In Rice And Field Evaluation Of Introgression Lines For Resistance And Yield Traits

Blast caused by Magnaporthe oryzae is the most devastating disease causing significant loss in rice production. The destructive nature of the disease is mainly due to the genetic plasticity of M.oryzae which complicates the breeding strategies. Blast can be effectively managed by the deployment of R genes. In this study, broad-spectrum blast resistance genes Pi2 and Pi5 were introgressed independently into popular but blast susceptible rice variety, Samba Mahsuri (BPT5204) by applying marker-assisted backcross breeding approach. Tightly linked markers AP5930 for Pi2 and 40N23r for Pi5 gene were used in foreground selection. Background selection helped to identify the lines with maximum recovery of recurrent parent genome (RPG). The RPG recovery in Pi2 introgression lines was up to 90.17 and 91.46% in Pi5 lines. Homozygous introgression lines in BC3F4 generation carrying Pi2 and Pi5 gene were field evaluated for blast resistance, yield per se and yield-related traits. The lines showed resistance to leaf and neck blast in multilocation field evaluation. Improved BPT5204 lines with improvement for blast resistance were on par with original BPT5204 in terms of grain yield and grain features.