Trait/QTL | Comments | References |
---|---|---|
Submergence tolerance (SUB1) | The SUB1 major gene was introduced by Marker Assisted Backcrossing (MABC) into IR64 and released in several countries. | (Septiningsih et al. 2009) |
Drought tolerance (DRO1) | Breeding line developed by MABC showed improved drought tolerance through deeper root system. | (Uga et al. 2013) |
Drought tolerance (qDTY2.2 + qDTY4.1) | Lines derived by MABC showed improved yield under severe drought stress. | (Swamy et al. 2013) |
SPIKE gene (NARROW LEAF1) | NIL with this gene showed 15–36% higher yield when introgressed into IR64. The gene increases spikelet number. | (Fujita et al. 2013). |
Improved agronomic traits | 334 introgression lines developed in IR64 background using tropical japonica donors | (Farooq et al. 2010; Fujita et al. 2009; Kato et al. 2010; Tagle et al. 2016) |
Anaerobic germination (AG1) | IR64-AG1 was developed by introgressing the AG1 QTL into IR64. | (Toledo et al. 2015) |
Yield QTL identified from O. rufipogon | Some QTLs from low yielding wild rice O. rufipogon can increase yield in IR64 background. | |
Drought tolerance from O. glaberrima | A population of alien introgression lines using an accession of African rice O. glaberrima backcrossed to IR64 (BC2), and identified QTLs associated with drought-related traits. | (Bimpong et al. 2011) |
Early-morning flowering (qEMF3) | NIL IR64 + qEMF3 with early morning flowering was developed using three backcrosses by marker assisted backcrossing and it flowered 1.5–2.0 h earlier in the day than IR64. In this case the donor was wild rice O. officinalis. This trait can confer tolerance to high temperature at anthesis. | (Hirabayashi et al. 2015) |
Tolerance to P deficiency (Pup1) | Tolerance of P deficiency was introduced into IR64-Pup1, with the Pup1 gene for more efficient P uptake. | |
Resistance to rice yellow mottle virus (RYMV) | Resistance to RYMV was introduced into IR64 background by marker assisted backcrossing. | (Ahmadi et al. 2001) |