Marker‐Assisted Development of Purple Aleurone Sweet Corn ( Zea mays L.) Inbreds With Enhanced Anthocyanin and Beta‐Carotene Accumulation

Sweet corn ( Zea mays L.) is a widely consumed vegetable crop; however, most commercial cultivars contain low levels of provitamin A carotenoids and anthocyanins, limiting their nutritional value. In this study, marker‐assisted backcross breeding was employed to simultaneously enhance beta‐carotene content, anthocyanin accumulation, and sweetness by introgressing the favourable crtRB1 allele, the recessive sh2 allele, and purple aleurone pigmentation into the elite sweet corn inbred DBT15 using the purple maize landrace Chujak Purple from the North‐Eastern Himalayan Region (NEHR) as the donor parent. Foreground selection for crtRB1 , phenotypic selection for purple kernel pigmentation and shrunken endosperm, and background selection using 102 polymorphic SSR markers facilitated the recovery of six stable BC 2 F 4 purple sweet corn introgression lines. Based on kernel pigmentation and anthocyanin composition, the lines were grouped into dark greyish‐purple and greyish‐purple types. At 24 days after pollination, the improved lines exhibited total soluble solids of 15.56–16.3°Brix, total sugars of 16.8%–17.57% and beta‐carotene concentrations of 7.25–8.20 μg/g, comparable to the recurrent parent DBT15 and substantially higher than the donor parent. High‐performance liquid chromatography identified cyanidin‐3‐glucoside, pelargonidin‐3‐glucoside and peonidin‐3‐glucoside as the predominant anthocyanins and evaluated across environments. These results demonstrate the successful development of biofortified purple super‐sweet corn combining enhanced provitamin A, elevated anthocyanin content and desirable sweetness, providing valuable germplasm for developing nutritionally superior sweet corn cultivars.