Incorporation of blast resistance into “PRR78”, an elite Basmati rice restorer line, through marker assisted backcross breeding

Pusa RH10, a popular high yielding superfine grain aromatic rice hybrid and its parents Pusa6A and PRR78 are highly susceptibility to blast disease. Marker assisted backcross breeding (MABB) approach was employed to incorporate blast resistance genes viz., Piz-5 and Pi54, from the donor lines C101A51 and Tetep into the genetic background of PRR78 to develop Pusa1602 (PRR78 + Piz5) and Pusa1603 (PRR78 + Pi54), respectively. Foreground selection for the genes Piz-5 and Pi54 was effected using tightly linked molecular markers, AP5930 and RM206, respectively in two independent backcross series. Further, foreground selection was coupled with stringent phenotypic selection for agronomic, grain and cooking quality traits, to accelerate recurrent parent phenome recovery. Five superior BC2F2 plants homozygous from each of the backcross series were selected and advanced to BC2F5 generation through pedigree selection to develop improved versions of PRR78 with blast resistance. Background analysis revealed the recurrent parent genome recovery up to 89.01% and 87.88% in Pusa1602 and Pusa1603 lines, respectively. The hybrids produced by crossing Pusa6A with improved lines of PRR78, were on par with original Pusa RH10 in terms of yield, grain and cooking quality traits with an added advantage of blast resistance.

► Piz-5 and Pi54 from non-Basmati donors transferred into a Basmati restorer, PRR78. ► Marker-assisted backcross strategy employing foreground and background selection. ► Developed improved restorers, Pusa1602 (with Piz-5) and Pusa1603 (with Pi54). ► Improved restorers and derived hybrids with good performance and blast resistance. ► Improved lines are valuable donors for blast resistance in Basmati breeding.