The genomes of 204 Vitis vinifera accessions reveal the origin of European wine grapes

In order to elucidate the still controversial processes that originated European wine grapes from its wild progenitor, here we analyse 204 genomes of Vitis vinifera and show that all analyses support a single domestication event that occurred in Western Asia and was followed by numerous and pervasive introgressions from European wild populations. This admixture generated the so-called international wine grapes that have diffused from Alpine countries worldwide. Across Europe, marked differences in genomic diversity are observed in local varieties that are traditionally cultivated in different wine producing countries, with Italy and France showing the largest diversity. Three genomic regions of reduced genetic diversity are observed, presumably as a consequence of artificial selection. In the lowest diversity region, two candidate genes that gained berry–specific expression in domesticated varieties may contribute to the change in berry size and morphology that makes the fruit attractive for human consumption and adapted for winemaking.

Changes in Berry Tissues in Monastrell Grapevines Grafted on Different Rootstocks and Their Relationship with Berry and Wine Phenolic Content

Monastrell grapevines grafted on the rootstocks 140Ru, 1103P, 41B, 110R, and 161-49C were subjected to regulated deficit irrigation (RDI) and partial root-zone irrigation (PRI). We analyzed the effects of the rootstock and irrigation method on the phenolic concentration in different berry tissues, its dilution/concentration due to the berry size, the anatomical and morphological traits of berries related to the phenolic compounds concentration, and the relationships of all these parameters with the final berry and wine phenolic content. The rootstock had an important effect on the accumulation of total phenolic compounds and anthocyanins in the skin (berries from 110R and 140Ru had the highest values). Moreover, the rootstock modified some anatomical and morphological characteristics that had a direct relationship with the final phenolic compounds concentration in the must. Large grapes and high must percentages (110R and 140Ru) produced a dilution effect, whereas small berries and a low must percentage increased the concentration (161-49C). For 110R, the small size of the cells of the epidermis and hypodermis in the grapes also could have contributed to the high phenolic compounds concentration in the skin. The percentage of cells in the skin with a uniform coloration was positively correlated with its total phenolic compounds and anthocyanins concentration and also with the phenolic quality of the wine. The PRI modified some specific morphological/anatomical skin/berry traits, and these may have contributed to important changes in the final concentration of phenolic compounds, depending on the rootstock. The better phenolic quality of the must and wines observed in some rootstocks under PRI could be due to smaller cells in the epidermis and hypodermis of the skin (161-49C), a higher percentage of cells with a uniform coloration in the hypodermis (110R), or a lower number of seeds per berry (161-49C). In contrast, the lower phenolic compounds concentration in the must of grapes observed in the most vigorous rootstocks under PRI could be due to a greater thickness of the epidermis (140Ru), greater cuticle thickness (41B), a higher number of seeds (140Ru), a lower skin/pulp ratio and percentage of skin (140Ru), a greater percentage of cells in the epidermis without coloration or with large inclusions, and a lower percentage of cells with a uniform coloration in the epidermis (140Ru). The final quality of the grape is related to some changes in histological and morphological aspects of the grape produced by the rootstock and irrigation strategy.

Influence of Plant Growth Regulators to Improve the Colour and Sugar Content of Grapes (Vitis vinifera L.). cv. Red Globe

Studies on Effect of plant growth regulators to improve the colour and sugar content of Grapes” (Vitis vinifera L.).cv. Red Globe was conducted in the field of a progressive grape grower at Kaalampalyam (10 O 58’49.17” N and 76 O 55’ 15. 81”E and elevation of 1352 ft from MSL) near Perur area of Coimbatore district in Tamil Nadu. The experiment was laid out in a randomized Block design with 7 treatments and each treatment was replicated four times. The data recorded on various parameters viz., vegetative growth, flowering, fruit yield, Quality etc., were statistically analysed. Significant differences were observed among the growth regulators on various vegetative growth parameters in Grapes (Vitis vinifera L.). cv. Red Globe. Among all the treatments, number of bunches per vine was significantly higher when sprayed with ethephon 200ppm (T4) compared to other treatments. (6.53 cm), the berry size and berry weight of the grapes were found to be maximum in the bunches treated with CCC 500ppm (T2) (6.57 g), There was no impact on the number of seeds by the treatments. The ethephon 200ppm (T4) treatment exhibited superior quality in terms of juice content, total sugars and colour value.

Effects of Berry Thinning on the Physicochemical, Aromatic, and Sensory Properties of Shine Muscat Grapes

The effects of the level of berry thinning (30% and 50% berry removal) on the quality and sensory properties of Shine Muscat grapes were investigated. As berry thinning increased, the total soluble solids content increased and titratable acidity decreased. Berry thinning increased berry size and cluster weight but caused no change in individual berry weight. Phenolic concentrations as measured by total phenolic, proanthocyanidin, and polymeric tannin concentrations tended to increase with an increase in berry thinning. Gas chromatographic analysis indicated that C6-compounds were the significant constituents of volatile alcohols and aldehydes; linalool was the most abundant monoterpene. Odor activity analysis indicated that (E)-2-hexen-1-ol, (E)-2-hexenal, 1-hexanal, (Z)-3-hexenal, (E)-β-damascenone, linalool, and (E)-linalool oxide were active odorants. Berry thinning increased the accumulation of linalool contributing to high sensory flavor scores in thinned berries. Furthermore, its oxidized derivative-linalool oxide-contributed to enhancing the Muscat flavor. In conclusion, berry thinning induced compositional changes in Shine Muscat grape berries by accelerating the ripening rate, contribution to improved sensory properties.

Grape Small Auxin Upregulated RNA (SAUR) 041 Is a Candidate Regulator of Berry Size in Grape

Grape (Vitis vinifera) is an important horticultural crop that can be used to make juice and wine. However, the small size of the berry limits its yield. Cultivating larger berry varieties can be an effective way to solve this problem. As the largest family of auxin early response genes, SAUR (small auxin upregulated RNA) plays an important role in the growth and development of plants. Berry size is one of the important factors that determine grape quality. However, the SAUR gene family’s function in berry size of grape has not been studied systematically. We identified 60 SAUR members in the grape genome and divided them into 12 subfamilies based on phylogenetic analysis. Subsequently, we conducted a comprehensive and systematic analysis on the SAUR gene family by analyzing distribution of key amino acid residues in the domain, structural features, conserved motifs, and protein interaction network, and combined with the heterologous expression in Arabidopsis and tomato. Finally, the member related to grape berry size in SAUR gene family were screened. This genome-wide study provides a systematic analysis of grape SAUR gene family, further understanding the potential functions of candidate genes, and provides a new idea for grape breeding.

Grape Berry Detection and Size Measurement Based on Edge Image Processing and Geometric Morphology

Counting grape berries and measuring their size can provide accurate data for robot picking behavior decision-making, yield estimation, and quality evaluation. When grapes are picked, there is a strong uncertainty in the external environment and the shape of the grapes. Counting grape berries and measuring berry size are challenging tasks. Computer vision has made a huge breakthrough in this field. Although the detection method of grape berries based on 3D point cloud information relies on scanning equipment to estimate the number and yield of grape berries, the detection method is difficult to generalize. Grape berry detection based on 2D images is an effective method to solve this problem. However, it is difficult for traditional algorithms to accurately measure the berry size and other parameters, and there is still the problem of the low robustness of berry counting. In response to the above problems, we propose a grape berry detection method based on edge image processing and geometric morphology. The edge contour search and the corner detection algorithm are introduced to detect the concave point position of the berry edge contour extracted by the Canny algorithm to obtain the best contour segment. To correctly obtain the edge contour information of each berry and reduce the error grouping of contour segments, this paper proposes an algorithm for combining contour segments based on clustering search strategy and rotation direction determination, which realizes the correct reorganization of the segmented contour segments, to achieve an accurate calculation of the number of berries and an accurate measurement of their size. The experimental results prove that our proposed method has an average accuracy of 87.76% for the detection of the concave points of the edge contours of different types of grapes, which can achieve a good edge contour segmentation. The average accuracy of the detection of the number of grapes berries in this paper is 91.42%, which is 4.75% higher than that of the Hough transform. The average error between the measured berry size and the actual berry size is 2.30 mm, and the maximum error is 5.62 mm, which is within a reasonable range. The results prove that the method proposed in this paper is robust enough to detect different types of grape berries.

The Effect of Water Deficit on Two Greek Vitis vinifera L. Cultivars: Physiology, Grape Composition and Gene Expression during Berry Development

Plants are exposed to numerous abiotic stresses. Drought is probably the most important of them and determines crop distribution around the world. Grapevine is considered to be a drought-resilient species, traditionally covering semiarid areas. Moreover, in the case of grapevine, moderate water deficit is known to improve the quality traits of grape berries and subsequently wine composition. However, against the backdrop of climate change, vines are expected to experience sustained water deficits which could be detrimental to both grape quality and yield. The influence of water deficit on two Greek Vitis vinifera L. cultivars, ‘Agiorgitiko’ and ‘Assyrtiko’, was investigated during the 2019 and 2020 vintages. Vine physiology measurements in irrigated and non-irrigated plants were performed at three time-points throughout berry development (green berry, veraison and harvest). Berry growth and composition were examined during ripening. According to the results, water deficit resulted in reduced berry size and increased levels of soluble sugars, total phenols and anthocyanins. The expression profile of specific genes, known to control grape color, aroma and flavor was altered by water availability during maturation in a cultivar-specific manner. In agreement with the increased concentration of phenolic compounds due to water deficit, genes of the phenylpropanoid pathway in the red-skinned Agiorgitiko exhibited higher expression levels and earlier up-regulation than in the white Assyrtiko. The expression profile of the other genes during maturation or in response to water deficit was depended on the vintage.

Quantitative analysis of the berry size in grapevine cultivar ‘Italia’ •

Quantitative evaluation of the horticultural crops has high importance to identify cultivars, describe the effect of the growing location and cultivation technology or define consumer's preference regarding the size and shape. Fruit traits of the grapevine (Vitis vinifera L.) are mainly described by the bunch and berry morphology notably bunch and berry size, weight and shape. Ampelographers particularly evaluate the berry based on the seed number as it influences size and consumers' decision. In this study, berry morphological traits of the grapevine cultivar ‘Italia’ was investigated based on digital image analysis. Samples were collected from two vineyards in Hungary with different ecological and cultivation circumstances. Altogether 12 traits were investigated: weight, seed number, size and shape attributes. Results showed that berry morphological traits – except from the shape attributes – are not differing between the two sampling locations. In accordance with previous studies, seed number – ranging from 0 to 4 – had noticeable effect on the size attributes.

Exogenous Calcium Delays Grape Berry Maturation in the White cv. Loureiro While Increasing Fruit Firmness and Flavonol Content

Vineyard calcium (Ca) sprays have been increasingly used by grape growers to improve fruit firmness and thus maintain quality, particularly in periods of heavy rains and hail. The observation that Ca visibly modified berry size, texture, and color in the most prominent white cultivar of the DOC region ‘Vinhos Verdes’, cultivar (cv.) Loureiro, led us to hypothesize that Ca induced metabolic rearrangements that resulted in a substantial delay in fruit maturation. Targeted metabolomics by ultra-performance liquid chromatography coupled to mass spectrometry and directed transcriptomics were thus combined to characterize the metabolic and transcriptional profiles of cv. Loureiro berries that, together with firmness, °Brix, and fruit weight measurements, allowed to obtain an integrated picture of the biochemical and structural effects of Ca in this cultivar. Results showed that exogenous Ca decreased amino acid levels in ripe berries while upregulating PAL1 expression, and stimulated the accumulation of caftaric, coutaric, and fertaric acids. An increase in the levels of specific stilbenoids, namely E-piceid and E-ω-viniferin, was observed, which correlated with the upregulation of STS expression. Trace amounts of anthocyanins were detected in berries of this white cultivar, but Ca treatment further inhibited their accumulation. The increased berry flavonol content upon Ca treatment confirmed that Ca delays the maturation process, which was further supported by an increase in fruit firmness and decrease in weight and °Brix at harvest. This newly reported effect may be specific to white cultivars, a topic that deserves further investigation.

Strawberry Crown Plugs Provide Flexibility and Improved Performance in Cold Climate Plasticulture Production

Annual plasticulture strawberry production has not been adopted as rapidly in cold climate regions as has occurred in warmer production areas due to uncertainty about potential benefits. Recent trials have demonstrated the potential of regionally adapted varieties in the annual plasticulture system in cold regions, but optimal production practices have not been determined. Summer planting of short-day varieties in these areas would increase flexibility for growers, allowing additional cropping options and improved land use management. The performance of six short-day strawberry varieties (Chandler, Clancy, Jewel, Ovation, Seneca and Ventana) was examined in a series of four annual production trials using cold-stored bare-root crowns for spring planting or a new type of planting stock termed a ‘crown plug’ for two summer plantings. Procedures for producing crown plugs from cold-stored crowns are described. The crown plug summer plantings significantly outperformed the spring planted bare-root plants across all varieties. The July planting established using crown plugs had higher yield and higher mean berry weight across all six varieties compared to the May bare-root planting (623 g/plant—12.5 g mean fruit weight vs. 330 g/plant—10.6 g mean fruit weight, respectively). In the July planting, ‘Seneca’, ‘Ventana’ and ‘Jewel’ exceeded the mean yield per plant for the planting as a whole and the other three varieties also produced more than previously reported for the May planting established with bare-root plants. The August crown plug planting was less productive than the July planting (623 g/plant vs. 498 g/plant, respectively) but was still more productive than both spring plantings. No difference was observed between the April and May plantings across the six varieties. Utilizing crown plugs also reduced the duration of weed control measures needed, improved efficiency of setting plants and limited the need for blossom and runner removal in the field, thus demonstrating labor cost savings that can offset the cost of crown plug production while also producing higher overall yield and mean fruit weight in the varieties in the trial. The summer plantings established with crown plugs demonstrated improved survival through a second winter dormancy period but produced relatively poor yield and berry size in the second harvest season. Crown plugs provide flexibility and improved productivity for growers utilizing annual plasticulture production in cold climate regions.