Project description:A double cropping system has been commercially adopted in subtropical regions in southern China, where there is abundant sunshine and heat resources. In this viticulture system, the first growing season normally starts as a summer cropping cycle; then, the vine is pruned and forced by hydrogen cyanamide, resulting in a second crop in January of the next year. Due to climate differences between the two growing seasons,the transcriptome varies greatly between summer- and winter- grape berries. In this study, we conducted RNA-seq for two table grape varieties (Vitis vinifera cv. Victoria and V. vinifera cv. Muscat Superior) at three developmental stages (pre-veraison, post-veraison and full maturity).The transcriptome between summer- and winter- grape berries were compared.
Project description:A double cropping system has been commercially adopted in subtropical regions in southern China, where there is abundant sunshine and heat resources. In this viticulture system, the first growing season normally starts as a summer cropping cycle; then, the vine is pruned and forced by hydrogen cyanamide, resulting in a second crop in January of the next year. Due to climate differences between the two growing seasons, flavonoid content and composition varies greatly. In this study, changes in the transcriptome of flavonoid-associated pathways were compared in berries grown under the double cropping system; in addition, the accumulation of flavonoid compounds was compared. Specific alterations in MYB transcription factors occurred in winter cropping berries around veraison. Then, the winter cropping cycle distinctly induced the flavonoid metabolic pathways while triggering the ripening-associated pathways. Notably, the climate conditions in winter cropping positively affected flavonoid biosynthesis, while the summer season took a major toll on anthocyanin accumulation. In addition, the three classes of flavonoid compounds responded differently to the changing climate; the anthocyanins and flavonols were promoted several fold, whereas no consistent increase was found for flavan-3-ols. Conclusively, flavonoid biosynthesis in grapes grown under a double cropping system showed seasonal or climatic-specific accumulation patterns.
