Genetic and Developmental Fortification of Sweet Corn \(\beta\)-carotene through Crosses with Field Corn

Abstract

The primary goal of this research is to employ field corn genes to improve the overall quality of sweet corn, particularly the \(\beta\)-carotene levels. Biofortification, which involves producing plants with greater nutrient composition, is one of the most significant methods for eliminating or minimizing nutrient shortages. Kernels and flour-Hunter b*values varied significantly among genotypes of 7 sweet corn, 8 field corn, and 3 F₁ field-sweet corn crosses studied. In the cross between inbred 2605-1288Y (yellow field corn "P₁₆") and Country Gentleman cv. (white sweet corn "P₁₉"), the flour yellowness index of the F₁ crosses was between the mid-parent and the lower parent, but larger than the better-parent throughout the cross between Inbred 82 (white field corn “P₁₂”) and Golden Bantam cv. (yellow sweet corn "P₂₀"). HPLC analysis of zeaxanthin,  \(\beta\)-cryptoxanthin, \(\alpha\) -carotene, and \(\beta\)-carotene quantities reported a significant heterogeneity in carotenoid content among genotypes and crosses. According to HPLC results, F₁ field-sweet corn crosses differed significantly in \(\alpha\) - and \(\beta\)-carotene. F₁ of P₁₂ x P₂₀ cross gathered the most zeaxanthin and \(\beta\)-cryptoxanthin, but F₁ of P₁₆ x P₁₉ cross and P₁₂ x P₉ cross accumulated much more \(\alpha\) - and \(\beta\)-carotene. The yellowness index was calculated using data from parents, F₁, F₂, and backcross populations in P₁₆ x P₁₉ cross and P₁₂ x P₂₀ cross. Both non-additive and additive gene effects had a considerable influence on the yellowness index, with the non-additive gene having a stronger dominant influence. This trait was inherited with a partial dominance towards the lower parent, and heritability estimates were relatively high in both wide and narrow senses. There was no evident correlation between grain colour and \(\beta\)-carotene, although polymorphisms in lycopene epsilon cyclase (lcyE), which is thought to govern the percentage of carotenes, revealed substantial changes in either \(\alpha\) - or \(\beta\)-branch carotenoids among genotypes and crosses. lcyE amplification was seen in two F₁ field-sweet corn crosses,P₁₂ x P₉ and P₁₆ x P₁₉ with high \(\beta\)-carotene content. The flavour of sweet corn can be enhanced by breeding with field corn. Along with \(\beta\)-carotene content, functional variation of LcyE among genotypes yielded significant results. Sweet corn genotypes that were tested were unable to amplify LcyE and had low levels of \(\beta\)-carotene, whereas field corn inbreds that were able to amplify LcyE had high levels of \(\beta\)-carotene. The results obtained constitute a vital breakthrough toward breeding more adaptive and nutritious sweet corn.