Molecular diversity and genetic variability of kernel tocopherols among maize inbreds possessing favourable haplotypes of γ-tocopherol methyl transferase ( ZmVTE4 )

Vitamin E deficiency is a serious health concern in humans. Biofortification of maize kernel with high vitamin E (α-tocopherol) provides sustainable and cost-effective solution. Here, a set of 24 inbreds possessing favourable alleles of γ-tocopherol methyl transferase (ZmVTE4) was analyzed. Significant variation for α-tocopherol (10.08–32.74 µg/g), γ-tocopherol (4.80–53.09 µg/g), δ-tocopherol (1.06–11.89 µg/g) and total tocopherol (20.18–97.72 µg/g) was observed. The mean α-tocopherol in the ZmVTE4-favourable genotypes was 20.23 µg/g compared to 4.75 µg/g in the unfavourable genotype. α-, γ- and δ-tocopherol constituted 39%, 48% and 13% of the total tocopherols, respectively, among positive lines. Molecular characterization of 24 lines using 80 SSRs generated 217 alleles. Wide variation was observed for PIC (0.08–0.73), gene diversity (0.08–0.76), major allele frequency (0.33–0.96) and dissimilarity coefficient (0.37–0.77). Cluster diagram grouped the inbreds into three distinct clusters consistent with the lineage. The study identified a set of potential cross combinations to develop high yielding hybrids enriched with vitamin E, and map additional gene(s) affecting accumulation of α-tocopherol. This is the first report on biochemical- and molecular- characterization of sub-tropically adapted inbreds with ZmVTE4-favourable allele.