Differential gene effectiveness and blast disease progression in MAS derived NILs in the background of aromatic rice landrace Mushk Budji

Mushk Budji is a premium quality scented rice landrace of Kashmir, which is highly susceptible to rice blast cause by Magnaporthe oryzae with more than 70% grain yield loss. Near-isogenic lines (NILs), namely, SKUA-27-4-40-9, SKUA-27-20-10-2 and SKUA-27-13-5-1, for the blast resistance genes, Pi54, Pi1 and Pita were successfully developed in the background of Mushk Budji. Marker-assisted foreground selection was carried out using gene-based and closely linked markers viz., Pi54 MAS (Pi54), RM224 (Pi1) and YL155/87 (Pita). The background analysis was done with 90 genome-wide distributed SSR markers linked to previously tagged SNPs, which helped in estimating the recurrent parent genome (RPG) recovery in the NILs. An area under the disease progress curve (AUDPC) was drawn to test the effectiveness of the individual-resistance genes in the developed NILs. A differential reaction pattern exhibited by the individual genes helped validate the respective genes’ effectiveness under the Kashmir conditions. The Pi54 and Pita were found to be effective in conferring resistance towards M. oryzae infection in the NILs of Mushk Budji.