(P10-26-26) Conventional Breeding and Multi-omics Approaches for Improving Antioxidant Qualities in Corn

Objectives: Decades of breeding staple grain crops for calories has come at the expense of nutrient content during the Green Revolution. Anthocyanins are potent antioxidants that reduce oxidative stress and inflammation linked to heart disease, type II diabetes, obesity, and neurodegeneration. This study aimed to improve nutritional qualities by developing an anthocyanin-enriched (Hi-A) corn variety while maintaining high. yield. Quantification of the metabolomic and transcriptomic profiles provides information about the regulation of anthocyanin in kernels over the course of development.

Methods: A Hi-A corn line was created by introgression of ancestral alleles into an elite background by the Texas A&M corn breeding program. The line was selected over multiple seasons for pigmentation, yield, drought tolerance, and heat tolerance. A total of 88 samples from Hi-A and yellow corn kernels were collected at three developmental time points from three greenhouse and two field environments. Glycosylated and acetylated cyanidins, pelargonidins, and peonidins were quantified at multiple kernel developmental stages using HPLC. Differential gene expression was conducted using yellow corn as a control at each time point. A supervised gene regulatory network (GRN) analysis was conducted using anthocyanin pathway genes as bait genes using SimpleTidyCoEx.

Results: Hi-A corn accumulated 100–800 times more anthocyanins than yellow corn, which varied depending on greenhouse or field environment. Expression of several key maize anthocyanin pathway genes such as Pr1 (F3’H), Bz1, Bz2, Aat1, PAL, CHS (chalcone synthase), and Pac1 were significantly higher in Hi-A corn compared to yellow corn. These genes showed strong co-regulation within environments, and similar expression levels in all environments. The GRN included anthocyanin structural genes and MBW transcription factors. Metabolite levels were positively correlated with gene expression as both were consistently upregulated in Hi-A corn compared to yellow corn.

Conclusions: Hi-A corn combines high anthocyanin content with yield and resilience to heat and drought. Elevated anthocyanin accumulation suggests strong cis-regulatory control of biosynthetic genes, supporting commercial scalability and improved nutritional value.

Funding Sources: This research was supported by USDA ARS.