The growing season impacts the accumulation and composition of flavonoids in grape skins in two-crop-a-year viticulture.
ABSTRACT: The influence of growing season (winter vs. summer) on the flavonoid accumulation and composition was studied in the skins of three grape cultivars for two consecutive years under a two-crop-a-year viticulture practice in Southwest China. The total anthocyanin, flavonol and flavan-3-ol contents in winter berry skins were significantly higher than those in summer berry skins for 'Kyoho' and 'Muscat Hamburg'. Reversely, the content of anthocyanin in 'NW196' winter berry was lower than summer berry. However, the percentage of diglycosylated, trihydroxylated, methylated, and acylated anthocyanins, trihydroxylated and methylated flavonols, and flavan-3-ol polymers were higher in the summer berry skins than the winter berry skins among all the three grape cultivars. Winter climatic conditions were favorable to flavonoid accumulation for the non native grapes 'Kyoho' and 'Muscat Hamburg', while the summer climatic conditions were beneficial to anthocyanin accumulation for 'NW196' that has 50% genetic background from a local wild grape species Vitis quinquangularis. These seasonal variations of flavonoid accumulations and compositions in the grape skins were primarily contributed by different climatic factors, such as temperature, solar radiation, and rainfall.
Project description:In this work, four vacuolar H+-PPase (VHP) genes were identified in the grape genome. Among them, VvVHP1; 2 was strongly expressed in berry skin and its expression exhibited high correlations to anthocyanin content of berry skin during berry ripening and under ABA and UVB treatments. VvVHP1; 2 was transcriptionally activated directly by VvMYBA1, and VvVHP1; 2 overexpression promoted anthocyanin accumulation in berry skins and Arabidopsis leaves; therefore, VvVHP1; 2 mediated VvMYBA1-regulated berry pigmentation. On the other hand, RNA-Seq analysis of WT and transgenic berry skins revealed that carbohydrate metabolism, flavonoid metabolism and regulation and solute carrier family expression were the most clearly altered biological processes. Further experiments elucidated that VvVHP1; 2 overexpression up-regulated the expression of the genes related to anthocyanin biosynthesis and transport via hexokinase-mediated glucose signal and thereby promoted anthocyanin accumulation in berry skins and Arabidopsis leaves. Additionally, modifications of sugar status caused by enhanced hexokinase activities likely play a key role in VvVHP1; 2-induced sugar signaling.
Project description:The aim of this study was to explore the relationships between structure alterations and postharvest berry abscission in "Muscat Kyoho" "Kyoho" and "Nanyu" table grapes stored for 0, 3, or 6 days at room temperature. Microstructure analysis showed that a large number of the stalk-berry junction cells of "Muscat Kyoho" and "Kyoho" were lignified and suberized at 0 day, whereas these events seldom occurred in "Nanyu."Furthermore, the berry brush cells of the three varieties, especially those of "Nanyu," were small and dense. At 3 days, the numbers of lignified and suberized cells of "Muscat Kyoho" and "Kyoho" were reduced, and the cells had degraded, ruptured, and disappeared by 6 days. The berry brush cells of "Muscat Kyoho" and "Kyoho" were larger and more loosely arranged than were those of "Nanyu." Ultrastructure analysis showed that the cells increased in size from small to large and became loosely arranged; the smallest changes were observed in "Nanyu." The cells of "Muscat Kyoho" and "Kyoho" were hydrolyzed, liquated, and covered by granular substances at 6 days, and these features were especially prominent in "Muscat Kyoho." The detachment force of grapes declined steadily (p < 0.05) and was accompanied by an increase in berry abscission. "Nanyu" maintained the highest detachment force and the lowest berry abscission during storage (p < 0.05), followed by "Kyoho" and "Muscat Kyoho." Structural alterations were directly related to berry abscission and correlated inversely with detachment force, with the greatest alterations occurring in "Muscat Kyoho," followed by "Kyoho" and then "Nanyu."
Project description:To fully utilize the characteristic climatic conditions in the southern region of China, a two-crop-a-year cultivation system technique for 'Kyoho' grape was developed during the past decade. After summer harvest in June, appropriate pruning and chemical treatments promote flowering and fruiting, which enables a second harvest in late December. Due to climatic differences between the two crop growing seasons, grape phenol and carotenoid metabolism differ greatly. The reported study analyzed the transcriptome of the carotenoid and phenylpropanoid/flavonoid pathways in grapes at four different stages during the two growing seasons. Compared with those in summer grapes, expression levels of the majority of genes involved in the carotenoid metabolic pathway in winter grapes were generally upregulated. This result was associated with lower rainfall and much more abundant sunlight during the second growing season. On the other hand, summer cropping strongly triggered the expression of upstream genes in the phenylpropanoid/flavonoid pathway at E-L 33 and E-L 35. Transcript levels of flavonoid 3',5'-hydroxylase (F3'5'H), flavonoid 3'-hydroxylase (F3'H), flavonoid 3-hydroxylase (F3H) and glutathione S-transferase (GST) were upregulated in winter grapes at the mature stage. Together, these results might indicate that more flavonoids would be synthesized in ripe winter grapes during the mature stage of the second crop under much drier conditions, longer sunlight hours and lower temperature. These data provide a theoretical foundation for the secondary metabolism of berries grown under two-crop-a-year cultivation systems.
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. Overall design: Differentially expressed genes between summer- and winter- grape berries were identified by DESeq2. And the transcriptome between summer- and winter- grape berries were compared.
Project description:Climatic conditions and soil type have significant influence on grape ripening and wine quality. The reported study was conducted in two "Cabernet Sauvignon (Vitis vinifera L.V)" vineyards located in Xinjiang, a semiarid wine-producing region of China during two vintages (2011 and 2012). The results indicate that soil and climate affected berry growth and anthocyanin profiles. These two localities were within a distance of 5 km from each other and had soils of different physical and chemical composition. For each vineyard, the differences of anthocyanin concentrations, and parameters concerning berry growth and composition between the two years could be explained by different climatic conditions. Soil effect was studied by investigation of differences in berry composition and anthocyanin profiles between the two vineyards in the same year, which could be explained mainly by the different soil properties, vine water and nitrogen status. Specifically, the soils with less water and organic matter produced looser clusters, heavier berry skins and higher TSS, which contributed to the excellent performance of grapes. Compared with 2011, the increases in anthocyanin concentrations for each vineyard in 2012 could be attributed to smaller number of extreme temperature (>35 °C) days and rainfall, lower vine water status and N level. The explanation for higher anthocyanin concentrations in grape skins from the soils with less water and organic matter could be the vine status differences, lighter berry weight and heavier skin weight at harvest. In particular, grapes from the soils with less water and organic matter had higher levels of 3'5'-substituded, O-methylated and acylated anthocyanins, which represented a positive characteristic conferring more stable pigmentation to the corresponding wine in the future. The present work clarifies the effects of climate and soil on berry growth and anthocyanin profiles, thus providing guidance for production of high-quality wine grapes in different regions.
Project description:Drought, elevated air temperature, and high evaporative demand are increasingly frequent during summer in grape growing areas like the Mediterranean basin, limiting grapevine productivity and berry quality. The foliar exogenous application of kaolin, a radiation-reflecting inert mineral, has proven effective in mitigating the negative impacts of these abiotic stresses in grapevine and other fruit crops, however, little is known about its influence on the composition of the grape berry and on key molecular mechanisms and metabolic pathways notably important for grape berry quality parameters. Here, we performed a thorough molecular and biochemical analysis to assess how foliar application of kaolin influences major secondary metabolism pathways associated with berry quality-traits, leading to biosynthesis of phenolics and anthocyanins, with a focus on the phenylpropanoid, flavonoid (both flavonol- and anthocyanin-biosynthetic) and stilbenoid pathways. In grape berries from different ripening stages, targeted transcriptional analysis by qPCR revealed that several genes involved in these pathways-VvPAL1, VvC4H1, VvSTSs, VvCHS1, VvFLS1, VvDFR, and VvUFGT-were more expressed in response to the foliar kaolin treatment, particularly in the latter maturation phases. In agreement, enzymatic activities of phenylalanine ammonia lyase (PAL), flavonol synthase (FLS), and UDP-glucose:flavonoid 3-O-glucosyltransferase (UFGT) were about two-fold higher in mature or fully mature berries from kaolin-treated plants, suggesting regulation also at a transcriptional level. The expression of the glutathione S-transferase VvGST4, and of the tonoplast anthocyanin transporters VvMATE1 and VvABCC1 were also all significantly increased at véraison and in mature berries, thus, when anthocyanins start to accumulate in the vacuole, in agreement with previously observed higher total concentrations of phenolics and anthocyanins in berries from kaolin-treated plants, especially at full maturity stage. Metabolomic analysis by reverse phase LC-QTOF-MS confirmed several kaolin-induced modifications including a significant increase in the quantities of several secondary metabolites including flavonoids and anthocyanins in the latter ripening stages, probably resulting from the general stimulation of the phenylpropanoid and flavonoid pathways.
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. Overall design: Total RNA obtained from deseed grape berries of of Cabernet Sauvignon and Riesling at three developmental stages (E-L 35, 36 and 38) in winter cropping compared to summer control crops.
Project description:BACKGROUND:'Fengzao' is an early-ripening bud mutant of 'Kyoho', which matures nearly 30 days earlier than 'Kyoho'. To gain a better understanding of the regulatory role of miRNAs in early-ripening of grape berry, high-throughput sequencing approach and quantitative RT-PCR validation were employed to identify miRNAs at the genome-wide level and profile the expression patterns of the miRNAs during berry development in 'Kyho' and 'Fengzao', respectively. RESULTS:Nine independent small RNA libraries were constructed and sequenced in two varieties from key berry development stages. A total of 108 known miRNAs and 61 novel miRNAs were identified. Among that, 159 miRNAs identified in 'Fengzao' all completely expressed in 'Kyoho' and there were 10 miRNAs specifically expressed in 'Kyoho'. The expression profiles of known and novel miRNAs were quite similar between two varieties. As the major differentially expressed miRNAs, novel_144, vvi-miR3626-3p and vvi-miR3626-5p only expressed in 'Kyoho', vvi-miR399b and vvi-miR399e were down-regulated in 'Fengzao', while vvi-miR477b-3p up-regulated in 'Fengzao'. According to the expression analysis and previous reports, miR169-NF-Y subunit, miR398-CSD, miR3626-RNA helicase, miR399- phosphate transporter and miR477-GRAS transcription factor were selected as the candidates for further investigations of miRNA regulation role in the early-ripening of grape. The qRT-PCR analyses validated the contrasting expression patterns for these miRNAs and their target genes. CONCLUSIONS:The miRNAome of the grape berry development of 'Kyoho', and its early-ripening bud mutant, 'Fengzao' were compared by high-throughput sequencing. The expression pattern of several key miRNAs and their target genes during grape berry development and ripening stages was examined. Our results provide valuable basis towards understanding the regulatory mechanisms of early-ripening of grape berry.
Project description:Anthocyanins are antioxidants and are among the natural products synthesized via the flavonoid biosynthesis pathway. Anthocyanins have been recommended for dietary intake in the prevention of cardiovascular diseases, cancer, and age-related conditions such as Alzheimer's disease or dementia. With an increasingly aging population in many parts of the world, strategies for the commercial production of in vitro synchronized red cell cultures as natural antioxidants will be a significant contribution to human medicine. Red pigmented fruits such as grapes (Vitis sp.) are a major source of bioavailable anthocyanins and other polyphenols. Since the level of antioxidants varies among cultivars, this study is the first one that phytochemically and genetically characterizes native grape cultivars of North America to determine the optimal cultivar and berry cells for the production of anthocyanins as antioxidants. Using real-time PCR and bioinformatics approaches, we tested for the transcript expression of the chalcone synthase (CHS) gene, an enzyme involved in the flavonoid and anthocyanin biosynthesis pathway, in different parts of physiologically mature grape berries and in vitro synchronized red cells. A low level of expression was recorded in berry flesh, compared with an elevated expression in berry skins and in vitro synchronized red cells, suggesting increased production of flavonoids in skin and cell cultures. This preliminary study demonstrates the potential of functional genomics in natural products research as well as in systematic studies of North American native grapes, specifically in muscadine (Vitis rotundifolia).
Project description:A double cropping system has been commercially adopted 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, resulting in a second crop in winter. Due to climate differences between the summer and winter growing seasons, grape ripening progression and flavonoid metabolism vary greatly. Here, the metabolites and transcriptome of flavonoid pathways were analyzed in grapes grown under two growing seasons at different stages. Notably, the winter cropping cycle strongly increased flavonoid levels by several times in comparison to summer grapes, while the summer season took a major toll on anthocyanin and flavonol accumulation, since the winter cropping greatly triggered the expression of upstream genes in the flavonoid pathway in a coordinated expression pattern. Moreover, the ratio of VviF3'5'Hs (flavonoid 3'5'-hydroxylase) to VviF3'Hs (flavonoid 3'-hydroxylase) transcript levels correlated remarkably well with the ratio of 3'5'-substituted to 3'-substituted flavonoids, which was presumed to control the flux of intermediates into different flavonoid branches. On the other hand, the phenological phase also varied greatly in the two crops. Compared to summer cropping, winter growing season accelerated the duration from budburst to veraison, therefore advancing the onset of ripening, but also prolonging the duration of ripening progression due to the purposes to harvest high-quality grapes. The differential expression pattern of hormone-related genes between the two cropping cycles might explain this phenomenon.