Photoperiod and water-deficient conditions differentially regulate structural flavonoid biosynthetic genes in peanuts

ABSTRACT Peanut (Arachis hypogaea L.) harbors a plethora of flavonoids that impart its health-promoting properties. To understand its biosynthesis and accumulation, a comparative expression analysis of flavonoid biosynthetic genes encoding enzymes responsible for synthesizing the main structure of flavonoids has been conducted in two differentially performing peanut varieties (PG 1247 and Bari 2011) in response to photoperiod and water availability. Transcript profiling of flavonoid biosynthetic genes indicated time-dependent expression of genes except for AhFLS in selected varieties in response to photoperiod variation. Many genes depicted a low degree of variation within varieties and water-deficient treatments. However, AhANS showed the highest variation for stress duration and varieties. In conclusion, this study has characterized the role of flavonoid biosynthesis in peanuts in response to photoperiod and water availability. Moreover, correlation analysis unraveled the coordination among the expression of flavonoid biosynthetic genes.