Work

Pyramiding of multiple resistant genes of blast and bacterial blight diseases in the background of rice (Oryza sativa) mega variety BRRI dhan29

Year: 2024

Type: article

Abstract: Blast and bacterial blight (BB) are the two major rice diseases in the world including Bangladesh. In this study, BB resistance genes ( Xa21 and xa13 ) and blast resistance ( Pi9 and Pb1 ) genes were pyramided into a mega variety, BRRI dhan29 through marker-assisted backcross breeding . IRBB58 was used as a BB-resistant donor and Pi9-US2, and Pb1-US2 were used as blast-resistant donors. Backcross was done between BRRI dhan29 and donor parents to develop BC 3 F 1 population and then selfing was done to develop BC 3 F 6 population. BC 3 F 2 population was genotyped and phenotyped for segregation analysis and BC 3 F 6 was evaluated for genotyping, phenotyping and morphological traits and yields. Chi-square analysis of BC 3 F 2 data revealed that blast and BB resistance followed the single gene mendelian fashion (1:2:1 and 3:1). Two to four gene combinations were found in the advanced lines of the BC 3 F 6 population. The yield of the advanced lines ranged from 6.42 (t ha −1 ) to 9.5 (t ha −1 ) and they showed resistant against blast and BB with mean disease scores ranging from 0.67 to 2.33 and 0.33–2.33, respectively. Finally, eight lines having four genes ( xa13, Xa21, Pi9 and Pb1 ) were selected for multilocational (five locations) trials for yield performance and disease reaction. Mean yield data of eight advanced lines of all locations were varied from 6.48±0.15–8.38±0.11 t ha −1 and all the lines showed resistant reactions against blast (score 0.53–1) and BB (score 0.6–0.87) disease. The highest yield was found in BR (Path) 13800-BC3–224–12 (G28, 8.38±0.11 t ha −1 ) followed by BR (Path) 13800-BC3–134–252 (G26, 8.28±0.08 t ha −1 ) and BR (Path) 13800-BC3–136–115 (G12, 8.24±0.07 t ha −1 ). Pyramided advanced lines of this study could be released as BB and blast-resistant varieties or could be utilized as donor parents in resistant breeding.

Source: Current Plant Biology

DOI: 10.1016/j.cpb.2024.100400