Table 1.
Breeding history of the low phytate basmati rice mutants with improved germination and yield.
| Year | Generations | Breeding task along with selection criteria | Total population/mutants/Crosses/Plants/Progenies | Selections |
|---|---|---|---|---|
| 2009–10 | Low phytate mutant lines in Super Basmati background | Low phytate mutants (∼54-63% reduction in phytic acid) with poor germination and yield were obtained through gamma radiations (60Co source) at 250 Gy dose under an IAEA project RAS/7/014 | 80000 | 03 (Lpa5, Lpa 9 and Lpa59) |
| 2010–11 | F0 | Two Lpa mutant lines (Lpa5 and Lpa59) were selected for crossing with Super Basmati due to their relatively better germination and yield. Following crosses were attempted: Lpa5 × Super Basmati, Lpa59 × Super Basmati, Super Basmati × Lpa5, Super Basmati × Lpa59 | 20 | Seed bulked crosswise |
| 2011–12 | F1 | Raising and selfing of F1 generation in field | 72 | Seed bulked crosswise |
| 2012–13 | F2:3 | Single plant selection on the basis of low phytate trait and germination percentage | 337 (Homozygous low phytate 226, heterozygous 65 and wild type rejected 46 plants) | 291 |
| 2013–14 | F3:4 | Selection of single plant progenies on the basis of low phytate trait | 291 (Homozygous progenies 86, heterozygous 71and wild type rejected progenies 134) | 86 |
| Selection of single plant progenies on the basis of better plant type, grain quality and presence of low phytate trait | 86 | 38 | ||
| 2012–13 | BC1 F1:2 | Four back cross populations were obtained by crossing of parent variety super basmati with F1 generation of all four cross combinations. | 56 | Seed bulked crosswise |
| 2013–14 | BC1 F2:3 | Raised in the field and single plants were selected on the basis of yield and yield contributing traits | 220 | 1st BC1 F2:3 (09) 2nd BC1 F2:3 (38) 3rd BC1 F2:3 (11) 4th BC1 F2:3 (53) |
| Screening for low phytate trait and selection of homozygous plants | 111 | 02 | ||
| 2014–15 | BC1 F3:4 | Out of 111 plant progenies from four BC1 F2:3 populations, 109 were raised in the field. Selections were continued for desirable agronomic and homozygosity for the low phytate trait. | 109 | 02 |
| 2015–16 | Evaluation of selected homozygous low phytate lines in preliminary yield trials and selection of best lines on the basis of yield and associated traits | 42 | 07 | |
| 2016–17 | Identification and characterization of Lpa mutations using molecular markers | – | – |