Effects of plant hormones and shading on the accumulation of anthocyanins and the expression of anthocyanin biosynthetic genes in grape berry skins

Anthocyanins are important grape components for red wine making. Here we examined the effects of plant hormones, abscisic acid (ABA) and naphthaleneacetic acid (NAA), and shading treatments on the accumulation of anthocyanins and the expression of anthocyanin biosynthetic genes in grape berry skins. The accumulation of anthocyanins was enhanced by ABA treatment and suppressed by NAA and shading. ABA enhanced the mRNA accumulation of VwnybAl, a putative regulatory gene of anthocyanin biosynthesis of grape, and all the tested enzyme genes of the anthocyanin biosynthetic pathway, while NAA and shading suppressed and retarded them. The change of the mRNA copy number of VvmybAl coincided with that of all the tested anthocyanin biosynthetic enzyme genes and the accumulation of anthocyanins. We also showed that there were significant differences in the mRNA copy number among three Chss, between two Chis, and two F3hs during the coloration of grape berry skins. (C) 2004 Elsevier Ireland Ltd. All rights reserved.