Genetic Improvement of Manipur Black Scented Rice Chakhao Poireiton Through Marker-Assisted Introgression of Novel Semidwarfing Allele, sd1bm

Abstract

Chakhao Poireiton, a traditional aromatic black rice landrace from Manipur, popularly known as Manipur black rice, protected under the Geographical Indications (GI) of India, is valued for its anthocyanin-rich pericarp and high antioxidant potential. However, its tall stature and susceptibility to lodging limit yield and grain quality. To address this, a novel semidwarfing allele, sd1^bm, was introgressed from the donor parent Pusa 1652 into Chakhao Poireiton using marker-assisted backcross breeding (MABB). The breeding strategy combined offseason generation advancement, stringent phenotypic selection, foreground selection for sd1^bm, and background selection to accelerate the recovery of the recurrent parent genome. The resulting semidwarf near-isogenic lines (NILs) demonstrated superior agronomic performance, with grain yields ranging from 4167 ± 25.6 to 5501 ± 40.5 kg/ha, compared to 3463 ± 10.5 kg/ha in Chakhao Poireiton. Several NILs exhibited significantly higher total anthocyanin content (169 ± 2.1 to 260.6 ± 5.4 mg/100 g DW), low amylose, and strong aroma. High genome recovery confirmed their near isogenicity with Chakhao Poireiton. Multilocation adaptability trials across GI regions of Manipur further established a yield advantage of up to 27.1% over the original landrace. These findings hold significant promise for enhancing the productivity and livelihood security of Chakhao Poireiton farmers.