Exogenous 24-Epibrassinolide Interacts with Light to Regulate Anthocyanin and Proanthocyanidin Biosynthesis in Cabernet Sauvignon (Vitis vinifera L.)

Abstract

Anthocyanins and proanthocyanidins (PAs) are crucial factors that affect the quality of grapes and the making of wine, which were stimulated by various stimuli and environment factors (sugar, hormones, light, and temperature). The aim of the study was to investigate the influence of exogenous 24-Epibrassinolide (EBR) and light on the mechanism of anthocyanins and PAs accumulation in grape berries. Grape clusters were sprayed with EBR (0.4 mg/L) under light and darkness conditions (EBR + L, EBR + D), or sprayed with deionized water under light and darkness conditions as controls (L, D), at the onset of veraison. A large amount of anthocyanins accumulated in the grape skins and was measured under EBR + L and L treatments, whereas EBR + D and D treatments severely suppressed anthocyanin accumulation. This indicated that EBR treatment could produce overlay effects under light, in comparison to that in dark. Real-time quantitative PCR analysis indicated that EBR application up-regulated the expression of genes (VvCHI1, VvCHS2, VvCHS3, VvDFR, VvLDOX, VvMYBA1) under light conditions. Under darkness conditions, only early biosynthetic genes of anthocyanin biosynthesis responded to EBR. Furthermore, we also analyzed the expression levels of the BR-regulated transcription factor VvBZR1 (Brassinazole-resistant 1) and light-regulated transcription factor VvHY5 (Elongated hypocotyl 5). Our results suggested that EBR and light had synergistic effects on the expression of genes in the anthocyanin biosynthesis pathway.

Comparative physiological, metabolomic, and transcriptomic analyses reveal developmental stage-dependent effects of cluster bagging on phenolic metabolism in Cabernet Sauvignon grape berries

“…As a physically protective field practice, fruit bagging for a specific period prior to the harvest has been extensively used in several fruit crops to improve fruit color and quality, reduce mechanical fruit damage, sunburn of the fruit peel, and presence of pesticide residues, and also protect fruit from pathogens, pests, and birds [57–61]. Numerous efforts have focused on the influence of cluster bagging or artificial shading with light exclusion boxes during different developmental stages concerning berry ripening, phenolic accumulation and the expression of phenolic biosynthesis genes in grapes [7, 14, 15, 23, 24, 30, 34, 62]. A recent genome-wide transcriptome analysis of two red grape cultivars also advanced our knowledge regarding the mechanisms of light-controlled anthocyanin synthesis [9].…”

“…In contrast, auxin (2,4-dichlorohenoxyacetic acid and naphthaleneacetic acid) treatments delay the ripening progression and inhibit the expression of anthocyanin biosynthetic genes and accumulation of anthocyanins in grape berries [32, 80]. More recently, synergistic effects of exogenous EBR and light treatments on the induction of PAs and anthocyanin synthesis have been found [62]. Enhanced signal transductions of auxin, CTK, ABA, BR, SA and ETH have been observed in response to both cluster bagging (T1-treated berries at E-L 31 stage and T8-treated berries at E-L 36 stage) and bag removal (T8-treated berries at E-L 37 stage) treatments (Fig.…”

Comparative Metabolite and Gene Expression Analyses in Combination With Gene Characterization Revealed the Patterns of Flavonoid Accumulation During Cistus creticus subsp. creticus Fruit Development

“…Distinct hormone signaling pathways are known to be implicated in the regulation of the flavonoid pathway. In this context, the regulatory roles of abscisic acid (ABA) ( Lacampagne et al, 2010 ; Zifkin et al, 2012 ), jasmonate (JA) ( An et al, 2015 ; Delgado et al, 2018 ), ethylene ( Min et al, 2012 ), brassinosteroids ( Zhou et al, 2018 ), and other hormones have been proposed.…”

PcDWF1, a pear brassinosteroid biosynthetic gene homologous to AtDWARF1, affected the vegetative and reproductive growth of plants

“…The seedlings of a T-DNA mutant of AtDWF1, dim, had shorter hypocotyls than did the wild type seedlings in light [38,57]. In addition, mutants deficient in BR response and synthesis genes, such as cpd, det2, dwf1, dwf4, bri1, all showed a short hypocotyl phenotype in light [58,59]. However, many of the findings of BR-related studies have focused on hypocotyl growth in darkness.…”