Location: Grain Quality and Structure Research
Title: Genome-wide association study dissects the genetic architecture of polyphenols and antioxidant capacity in a sorghum diversified collectionAuthor
Rhodes, Davina | |
Gadgil, Priyadarshin | |
PERUMAL, RAMASAMY - Kansas State University | |
TESSO, TESFAYE - Kansas State University | |
Herald, Thomas |
Submitted to: Journal of Cereal Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 7/15/2016 Publication Date: 3/16/2017 Citation: Rhodes, D.H., Gadgil, P., Perumal, R., Tesso, T., Herald, T.J. 2017. Genome-wide association study dissects the genetic architecture of polyphenols and antioxidant capacity in a sorghum diversified collection. Journal of Cereal Science. 94(2):190-198. Interpretive Summary: Consumption of polyphenol-rich food is associated with decreased risk of several oxidative stress-related chronic diseases. Sorghum, a major cereal crop grown worldwide, has many polyphenol-containing accessions with high antioxidant activity in the grain. The natural diversified variation in sorghum grain polyphenols can be used to develop high yielding, health-promoting specialty food types through marker-assisted breeding. To identify new polyphenolic and antioxidant rich germplasm, we quantified total polyphenols, tannins, and antioxidant capacity of whole kernel flour in 266 accessions from the genetically and phenotypically diverse Sorghum Association Panel (SAP). This study identified specific accessions that can be exploited for health-promoting compounds. These accessions can be used by breeders to develop new parental lines and high yielding hybrids containing traits associated with health-promoting compounds. Technical Abstract: Consumption of polyphenol-rich food is associated with decreased risk of several oxidative stress-related chronic diseases. Sorghum, a major cereal crop grown worldwide, has many polyphenol-containing accessions with high antioxidant activity in the grain. However, many of these polyphenol-containing accessions are not high-yielding or food-grade varieties. The natural diversified variation in sorghum grain polyphenols can be used to develop high yielding, health-promoting specialty food types through marker-assisted breeding. To identify new polyphenolic and antioxidant rich germplasm, we quantified total polyphenols, tannins, and antioxidant capacity of whole kernel flour in 266 accessions from the genetically and phenotypically diverse Sorghum Association Panel (SAP). Total polyphenols, tannins, and antioxidant values ranged from 0.8 -18.8 g GAE/kg, non-detectable - 65.5 g CE/kg, and 8.0 - 325.1 µM TE/g, respectively. Twenty-one accessions were rich sources of antioxidant activity, with PI534144 (SC84; 325.1 CE g/kg) and PI534117 (SC991; 237.0 CE g/kg) possessing the highest values within the sorghum population studied. To identify quantitative trait loci (QTL) associated with sorghum polyphenol and antioxidant traits, we conducted a genome-wide association study (GWAS) with 404,628 SNP markers. The analysis identified many significant associations, including homologs of Arabidopsis (Arabidopsis thaliana) TT10 and TT4. This study provides information that may help breeders to develop new parental lines and high yielding hybrids containing traits associated with health-promoting compounds. |