Development of β-carotene and anthocyanin rich quality protein maize using marker assisted selection

The present study reports the successful development of a nutritionally enhanced, anthocyanin-rich Quality Protein Maize (QPM) composite, EU-AQPAN, through marker-assisted back cross breeding (MABB). Two target genes (Pl1 and B) of the donor parent and two (o2 and crtRB1) of the recipient EU-AQP Composite were pyramided using linked molecular markers. Co-dominant SSR markers viz., umc1066, umc1014, umc1024, and a gene based marker crtRB1, were validated across parental lines and used in successive generations to track trait introgression. The breeding process was initiated in Kharif 2016 and culminated strict in the BC₂F₃ generation in 2024. The foreground selection for pigmentation and nutritional quality using linked molecular markers followed by regular phenotypic selection for background recovery due to the composite nature of the recurrent parent. The resulting EU-AQPAN lines exhibited deep purple kernel pigmentation and were homozygous for target alleles. The biochemical assays confirmed elevated lysine (4.13 g/100 g), tryptophan (2.26 g/100 g), and β-carotene (~ 3.58 mg/100 g), with anthocyanin levels: cyanidin-3-glucoside (206.21 mg/100 g), pelargonidin-3-glucoside (96.37 mg/100 g), and delphinidin-3-glucoside (2.36 mg/100 g) comparable to the conventional purple maize. This study demonstrates, for the first time, the successful pyramiding of quality protein (o2), provitamin A (crtRB1), and anthocyanin regulatory genes (Pl1, B) into an open-pollinated maize composite using marker-assisted selection.

The online version contains supplementary material available at 10.1007/s11032-026-01667-4.