Fig 1.
Schematic representation of marker assisted pedigree breeding.
Fig 2.
Screening of selected F5 generation lines with marker specific for target genes/QTL (A) Screening with pTA248 marker for Xa21, (B) Screening with Pi54MAS marker for Pi54 (C) Screening with K20-2 Bsp1 marker for Pup1. L-100bp ladder; RP: RP5973-20-9-8-24-12-7; Pup1, i.e., negative control for Xa21 and Pi54 and positive control for Pup1; RP: RP6132; Xa21 & Pi54, i.e., positive control for Xa21 and Pi54 and negative control for Pup1; 1–15: selected F5 lines. All the selected lines were homozygous for the target genes/QTL.
Fig 3.
Screening of selected breeding lines at F5 generation for their resistance against bacterial blight and blast (A) Screening for bacterial blight resistance using Xoo (DX-020) culture. ISM- Resistant check; TN1- Susceptible check; IL-1 to IL-4- Improved breeding lines (LPK 28-19-15, LPK 38-18-16, LPK 49-1-21 and LPK 49-15-22) possessing Pup1, Xa21 and Pi54 (F5 generation). (B) Phenotypic screening for blast resistance using SPI-40 fungal spore culture. A: Male Parent- Akshayadhan NIL (RP6132, (Xa21 & Pi54) H: Susceptible check-HR 12, M: Female Parent -MTU 1010 (RP5973-20-9-8-24-12-7; Pup1), IL-1 to IL-10: Improved breeding lines possessing Pup1, Xa21 and Pi54 (F5 Generation). All the selected breeding lines were resistant to bacterial blight and blast diseases. Four breeding lines i.e., IL-4: LPK 28-19-15, IL-7: LPK 38-18-16, IL-9: LPK 49-1-21 and IL-10: LPK 49-15-22, were highly resistant to blast disease with score 3).
Table 1.
Phenotypic screening of selected F5 breeding lines for BB and blast resistance at F5 generation.
Table 2.
Evaluation of the improved breeding lines (F5 generation) in plot with low soil P at ICAR-IIRR during wet season 2018.
Fig 4.
Performance of improved breeding lines under low P conditions.
(A) Root morphology of Improved breeding lines (IL-1 to IL-3; at F5 generation) possessing Pup1, Xa21 and Pi54 under low soil P condition. (B) Improved breeding lines (IL-1 to IL-3; at F5 generation) possessing Pup1, Xa21 and Pi54 under low soil P condition), M- Tolerant check—MTU 1010 (RP5973-20-9-8-24-12-7; Pup1), A- Sensitive check—Akshayadhan (RP6132; Xa21 & Pi54).
Fig 5.
Improved breeding lines performing better than the recurrent parent.
(A) Plant pictures (IL-1 to IL-3) and (B) Panicle picture of Improved breeding lines possessing Pup1, Xa21 and Pi54 at F5 generation. M- Female parent (MTU 1010 (Pup1) (RP5973-20-9-8-24-12-7), A- Male parent (Akshayadhan (Xa21 & Pi54) (RP6132).
Table 3.
Evaluation of the improved breeding lines (F5 generation) for key agro-morphological traits in plot with normal soil P levels at ICAR-IIRR during wet season 2018.