Genetic variability and GxE interactions for total polyphenol content and antioxidant activity in white and red sorghums (Sorghum bicolor)

Sorghum has unique advantage in terms of its climate resilience and its grain composition with beneficial bioactive compounds. It is a very good source of bioactive compounds such as polyphenols and antioxidants. Breeding efforts for end-use identity-specific genotypes are required for increased profitability to the farmers. In this study, total polyphenol content (TPC) and free radical scavenging activity (FRSA) were estimated in 60 genotypes, comprising of white and red sorghums, over three years each with two replications. TPC ranged from 55.6 mg/100 g to 553.1 mg/100 g with the highest value in IS 30508. The highest antioxidant activity, measured as free radical scavenging activity, was observed in IS 16151. Though in general TPC and FRSA are high in red sorghums, not all red sorghums have high TPC and scavenging activity. Significant effects of genotype and environment were observed for all the characters. Correlation studies indicated the possibility of developing a high yielding line with high antioxidant activity. The information generated aids in identifying donors to develop end-use specific genotypes that are suitable as functional foods.