MYB-6 and LDOX-1 regulated accretion of anthocyanin response to cold stress in purple black carrot (Daucus carota L.).

Abstract

Anthocyanin, an essential ingredient of functional foods, is present in a wide range of plants, including black carrots. The current investigation was carried out to analyse the effect of cold stress on the expression of major anthocyanins and anthocyanin biosynthetic pathway genes, MYB6 and LDOX-1. Five cultivated carrotgenotypes belonging to the eastern group, having anthocyanin pigment, were used in the current study. The qRT-PCR analysis revealed that relative gene expression of transcription factor MYB-6 and LDOX1gene was highly expressed upon cold stress compared to non-stress samples. High-performance liquid chromatography-based quantification of Cyanidin 3-O-glucoside (Kuromanin chloride), Ferulic acid, 3,5-Dimethoxy-4-hydroxycinnamic acid (Sinapic acid), and Rutin revealed a significant increase in these major anthocyanins in response to cold stress when compared to control plants. We conclude that MYB6 and LDOX1 gene expression increases upon cold stress, which induces accumulation of major anthocyanins in purple black carrot and suggestsa possible cross-link between cold stress and anthocyanin biosynthesis in purple black carrot.