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Achieving optimal coloration in red table grapes, especially in warm-climate regions, presents significant challenges due to high temperatures that inhibit anthocyanin biosynthesis. Conventional methods to enhance grape coloration, including the use of abscisic acid (ABA), ethephon, foliar nutrient supplementation, and viticultural practices like cluster trimming and girdling, have limitations related to cost, regulatory restrictions, and potential adverse effects on grapes quality. This study proposes the application of tsikoudia, a traditional Greek alcoholic beverage, as a novel, sustainable, and cost-effective alternative to conventional practices. Tsikoudia, applied during the veraison stage, significantly improved the coloration of 'Crimson Seedless' and 'Red Globe' grapes by enhancing anthocyanin accumulation and altering color parameters. Specifically, lightness (L*), chroma (C*), and hue angle (h), measured using the CIE-Lab color system, were reduced, while the Color Index for Red Grapes (CIRG) was increased. Additionally, total anthocyanin content, determined through spectrophotometric analysis, also showed an increase. These changes indicate a more intense red coloration. This research highlights the effectiveness of tsikoudia in improving grape coloration and contributes to the development of more sustainable viticultural practices. [ABSTRACT FROM AUTHOR]

Abstract Background Drought is a significant abiotic stress that adversely affects plant growth, development, and metabolic processes, thereby reducing plant yield, quality, and production, and threatening global food security. In recent years, nanotechnology has emerged as a promising strategy to overcome the existing environmental challenges and has been tested on some plant species. But it is still awaiting investigation for grapevines. The aim of this study was to investigate the potential of selenium nanoparticles (Se-NPs) to modulate some morphological, physiological, and biochemical parameters in grapevine saplings (5 BB/Crimson Seedless, 41 B/Crimson Seedless, and 1103 P/Crimson Seedless) under drought stress conditions. Results In the study, Se-NP solutions at different concentrations (0 (control), 1, 10, and 100 ppm) were applied by the spray method to wet the entire green surface of grapevine saplings grown under well-irrigated (90–100% field capacity) and drought stress (40–50% field capacity) conditions. Our results showed that 10 ppm Se-NP concentration had the most positive effect, 1 ppm concentration showed limited effects, and 100 ppm concentration led to toxic effects, especially when combined with drought conditions. Se-NP applications at 10 ppm concentration improved the growth parameters (leaf number, leaf area, root fresh and dry weight, shoot fresh and dry weight, etc.) and increased the SPAD index of grapevine saplings under both normal and drought conditions. Additionally, 10 ppm Se-NP applications improved the relative water content (RWC) and stomatal conductance values, proportional to the increases in protein content. On the other hand, under drought conditions, the drought index, leaf temperature, membrane damage index, hydrogen peroxide (H2O2) content, and malondialdehyde (MDA) levels significantly decreased as a result of 10 ppm Se-NP applications, showing an opposite trend. Furthermore, the levels of proline, total phenolics, and antioxidant enzymes (CAT, SOD, and APX) that rose significantly due to drought stress were reduced by 10 ppm Se-NP applications, which also helped to lessen the oxidative stress caused by the drought. Conclusion The study concluded that foliar application of Se-NPs at 10 ppm significantly enhances drought tolerance in grapevine saplings by improving antioxidant defense, proline and protein accumulation, and overall growth, while lower concentrations are less effective and higher concentrations can cause phytotoxicity. These findings indicate that Se-NPs applications may hold promise not only for grapevines but also for mitigating drought stress effects and improving productivity in other economically important fruit species, warranting further exploration across diverse crop systems. Graphical Abstract

Background: Drought is a significant abiotic stress that adversely affects plant growth, development, and metabolic processes, thereby reducing plant yield, quality, and production, and threatening global food security. In recent years, nanotechnology has emerged as a promising strategy to overcome the existing environmental challenges and has been tested on some plant species. But it is still awaiting investigation for grapevines. The aim of this study was to investigate the potential of selenium nanoparticles (Se-NPs) to modulate some morphological, physiological, and biochemical parameters in grapevine saplings (5 BB/Crimson Seedless, 41 B/Crimson Seedless, and 1103 P/Crimson Seedless) under drought stress conditions. Results: In the study, Se-NP solutions at different concentrations (0 (control), 1, 10, and 100 ppm) were applied by the spray method to wet the entire green surface of grapevine saplings grown under well-irrigated (90–100% field capacity) and drought stress (40–50% field capacity) conditions. Our results showed that 10 ppm Se-NP concentration had the most positive effect, 1 ppm concentration showed limited effects, and 100 ppm concentration led to toxic effects, especially when combined with drought conditions. Se-NP applications at 10 ppm concentration improved the growth parameters (leaf number, leaf area, root fresh and dry weight, shoot fresh and dry weight, etc.) and increased the SPAD index of grapevine saplings under both normal and drought conditions. Additionally, 10 ppm Se-NP applications improved the relative water content (RWC) and stomatal conductance values, proportional to the increases in protein content. On the other hand, under drought conditions, the drought index, leaf temperature, membrane damage index, hydrogen peroxide (H2O2) content, and malondialdehyde (MDA) levels significantly decreased as a result of 10 ppm Se-NP applications, showing an opposite trend. Furthermore, the levels of proline, total phenolics, and antioxidant enzymes (CAT, SOD, and APX) that rose significantly due to drought stress were reduced by 10 ppm Se-NP applications, which also helped to lessen the oxidative stress caused by the drought. Conclusion: The study concluded that foliar application of Se-NPs at 10 ppm significantly enhances drought tolerance in grapevine saplings by improving antioxidant defense, proline and protein accumulation, and overall growth, while lower concentrations are less effective and higher concentrations can cause phytotoxicity. These findings indicate that Se-NPs applications may hold promise not only for grapevines but also for mitigating drought stress effects and improving productivity in other economically important fruit species, warranting further exploration across diverse crop systems. [ABSTRACT FROM AUTHOR]

The rest-breaking agent, hydrogen cyanamide (HC), can substitute insufficient chill unit accumulation in Vitis vinifera and induce uniform bud-break; however, due to its toxicity it is being banned. In South Africa, red seedless grapes, including V. vinifera Crimson Seedless (CS), are the largest table grape export group; therefore, replacing HC in V. vinifera CS is crucial. This study aimed to confirm the molecular triggers induced by HC and assess the bud-break-enhancing abilities of commercial plant biostimulants. Forced bud-break assay experiments using V. vinifera CS single-node cuttings and a small-scale field trial were performed. Results demonstrated that increased chill unit accumulation (CUA) reduced HC efficacy. Bud-break started between 10 and 20 days after treatment, irrespective of final CUA. The small-scale field trial found that HC 3% and biostimulants were similar to the negative control. The treatment of dormant grapevine compound buds with nitric oxide (NO), hydrogen peroxide (H2O2), and hypoxia trigger dormancy release to a certain extent, supporting the molecular models proposed for HC action. NO, H2O2, and hypoxia, in combination with PBs, may potentially replace HC; however, this needs to be confirmed in future experiments. [ABSTRACT FROM AUTHOR]

Achieving optimal coloration in red table grapes, especially in warm-climate regions, presents significant challenges due to high temperatures that inhibit anthocyanin biosynthesis. Conventional methods to enhance grape coloration, including the use of abscisic acid (ABA), ethephon, foliar nutrient supplementation, and viticultural practices like cluster trimming and girdling, have limitations related to cost, regulatory restrictions, and potential adverse effects on grapes quality. This study proposes the application of tsikoudia, a traditional Greek alcoholic beverage, as a novel, sustainable, and cost-effective alternative to conventional practices. Tsikoudia, applied during the veraison stage, significantly improved the coloration of ‘Crimson Seedless’ and ‘Red Globe’ grapes by enhancing anthocyanin accumulation and altering color parameters. Specifically, lightness (L*), chroma (C*), and hue angle (h), measured using the CIE-Lab color system, were reduced, while the Color Index for Red Grapes (CIRG) was increased. Additionally, total anthocyanin content, determined through spectrophotometric analysis, also showed an increase. These changes indicate a more intense red coloration. This research highlights the effectiveness of tsikoudia in improving grape coloration and contributes to the development of more sustainable viticultural practices.

The rest-breaking agent, hydrogen cyanamide (HC), can substitute insufficient chill unit accumulation in Vitis vinifera and induce uniform bud-break; however, due to its toxicity it is being banned. In South Africa, red seedless grapes, including V. vinifera Crimson Seedless (CS), are the largest table grape export group; therefore, replacing HC in V. vinifera CS is crucial. This study aimed to confirm the molecular triggers induced by HC and assess the bud-break-enhancing abilities of commercial plant biostimulants. Forced bud-break assay experiments using V. vinifera CS single-node cuttings and a small-scale field trial were performed. Results demonstrated that increased chill unit accumulation (CUA) reduced HC efficacy. Bud-break started between 10 and 20 days after treatment, irrespective of final CUA. The small-scale field trial found that HC 3% and biostimulants were similar to the negative control. The treatment of dormant grapevine compound buds with nitric oxide (NO), hydrogen peroxide (H2O2), and hypoxia trigger dormancy release to a certain extent, supporting the molecular models proposed for HC action. NO, H2O2, and hypoxia, in combination with PBs, may potentially replace HC; however, this needs to be confirmed in future experiments.

The aim of this study is to determine the phenolic and polysaccharidic composition, texture properties, and gene expression of new seedless table grape cultivars Timco™ and Krissy™ and compare them to the traditional table grape variety Crimson Seedless (Vitis vinifera L.), during ripening and in commercial postharvest conditions. According to the results, phenolic compounds were present in very different proportions. The total anthocyanins responsible for skin color increased during maturation and the majority anthocyanin in the three cultivars was peonidin-3-glucoside, followed by malvidin-3-glucoside. The phenolic compounds presented a different behavior (decreasing or increasing) during postharvest. The total skin soluble polysaccharides decreased during ripening and postharvest in Crimson Seedless and Krissy™ and remained constant from technological maturity to postharvest storage in Timco™. In all cultivars, the majority soluble polysaccharide fraction was that with a molecular mass between 500 and 35 KDa. The skin mechanical properties of table grapes were good parameters for differentiating varieties, with better results for the new cultivars, compared to the traditional Crimson Seedless, especially in postharvest. Genes involved in the flavonoid pathway and cell wall metabolism in skins exhibited an increase in expression from veraison to remaining constant at the end of the berry ripening. [ABSTRACT FROM AUTHOR]

Copyright of COMU Journal of Agriculture Faculty / ÇOMÜ Ziraat Fakültesi Dergisi is the property of Canakkale Onsekiz Mart University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fertilization through the addition of nano-fertilizers, added in very small quantities as a foliar spray on the vine canopy, has become one of the most effective methods in order to reduce the amount of mineral fertilizers. Therefore, this experiment was conducted on a 7 year-old "Crimson seedless" grapevines for successive seasons 2021 and 2022 to determine the optimum rates of "Nano-NPK" fertilizer to replace the "NPK" conventional fertilizer. Three concentrations of "Nano-NPK" were used as foliar application in three concentrations, Nano - NPK (200, 30, 200 ppm), Nano-NPK (400, 60, 400 ppm) and Nano-NPK (800,120, 800 ppm) replacing 50% of conventional fertilizer NPK compared to the soil addition of the conventional fertilizer NPK at (25, 25, 100 kg/Feddan) as a control. Our results showed that Nano-NPK fertilizer at (800, 120, 800 ppm) induced a significant increase in yield parameters, along with the chemical and physical characteristics of the vegetative growth as compared with the lower concentrations but there are no significant differences between it and the control. Thus, application of Nano-fertilizers was very effective in accelerating the clusters growth stages along with replacing the mineral fertilizers

The color of 'Crimson Seedless' berries is a major constraint in expanding marketing and export potential. The target of this investigation is to enhance the color and quality of 'Crimson Seedless' by using brassinolide (BL) and girdling treatments, individually and in combination, as an alternative to ethephon over two consecutive seasons. The obtained results revealed that the combined treatment BL at 2.0 mg/L and girdling recorded the highest significant yield values (17.78 ± 0.29 and 18.26 ± 0.23 kg/vine) in both seasons, respectively, in contrast to ethephon and girdling treatments which had no significant influence. Besides, BL 2.0 mg/L + girdling presented high levels of physicochemical characteristics of clusters and berries compared to the control. Concerning berry color assessment, ethepon followed by BL at 2.0 mg/L + girdling recorded the highest significant improvement in the red color, as indicated by Color Index of Red Grapes and visual assessment, and had similar and elevated levels of anthocyanin content. On the other hand, flavonoids (3.46 ± 0.03 and 3.66 ± 0.02 mg/100 g FW), and antioxidant capacity (2.37 ± 0.02 and 2.43 ± 0.06 IC50) were obviously increased with BL 2.0 mg/L + girdling, with a slight decrease than ethephon application. As for phenylalanine ammonia-lyase activity, the data show that it increased by ethephon (7.91 ± 0.02 and 8.01 ± 0.02 U mg−1 protein) and BL 2.0 mg/L + girdling (7.77 ± 0.04 and 7.79 ± 0.07 U mg−1 protein), compared to the control (3.69 ± 0.02 and 3.80 ± 0.01 U mg−1 protein) in both seasons, respectively. In terms of polyphenol oxidase activity, the increase in PPO was closely associated with PAL. Moreover, BL 2.0 mg/L + girdling was the most effective treatment for increasing dormant season parameters in both seasons, while ethephon spraying had no influence. All these confirmed that the combined treatment BL 2.0 mg/L + girdling exhibited a synergistic effect in improving the color and quality of 'Crimson Seedless'. [ABSTRACT FROM AUTHOR]

Crimson Seedless is a coloured seedless grape, gaining popularity in India for its attractive colour, bunch and berry quality with better shelf life. In cultivation of any seedless grape variety, application of GA3 at different stages is very much essential to produce good quality berries and bunches. However, this variety is highly sensitive to excess application of GA3 and practicing GA3 schedule similar to that of Thompson Seedless grapes adversely affects bunch quality. Hence, there was a need to standardize mild dose of GA3 just for rachis elongation which will help to reduce bunch compactness to a greater extent. Hence, an experiment was initiated to standardize concentration of GA3 for rachis elongation of Crimson Seedless grapes. Three different concentrations of GA3 {viz., 5 ppm (T1), 7.5 ppm (T2) and 10 ppm (T3)} were sprayed during pre bloom stage and compared with unsprayed control (T4). Among different treatments, pre-bloom spray of GA3@5 ppm could produce less compact bunches with highest average bunch weight, berry weight, berry length and TSS. However, bunches sprayed with 7.5 ppm and 10 ppm GA3 could also produce good quality bunches average berry weight and TSS was less. Because of severe coiling of rachis at 7.5 ppm and 10 ppm GA3 spraying, bunches were too straggly compared to spraying of 5 ppm GA3. The control bunches without GA3 spray produced very compact clusters with less average bunch weight, berry weight, berry diameter and berry length.

The aim of this study is to determine the phenolic and polysaccharidic composition, texture properties, and gene expression of new seedless table grape cultivars Timco™ and Krissy™ and compare them to the traditional table grape variety Crimson Seedless (Vitis vinifera L.), during ripening and in commercial postharvest conditions. According to the results, phenolic compounds were present in very different proportions. The total anthocyanins responsible for skin color increased during maturation and the majority anthocyanin in the three cultivars was peonidin-3-glucoside, followed by malvidin-3-glucoside. The phenolic compounds presented a different behavior (decreasing or increasing) during postharvest. The total skin soluble polysaccharides decreased during ripening and postharvest in Crimson Seedless and Krissy™ and remained constant from technological maturity to postharvest storage in Timco™. In all cultivars, the majority soluble polysaccharide fraction was that with a molecular mass between 500 and 35 KDa. The skin mechanical properties of table grapes were good parameters for differentiating varieties, with better results for the new cultivars, compared to the traditional Crimson Seedless, especially in postharvest. Genes involved in the flavonoid pathway and cell wall metabolism in skins exhibited an increase in expression from veraison to remaining constant at the end of the berry ripening.

Some plant growth regulators, including ethephon, can stimulate abscission of mature grape berries. The stimulation of grape berry abscission reduces fruit detachment force (FDF) and promotes the development of a dry stem scar, both of which could facilitate the production of high quality stemless fresh-cut table grapes. The objective of this research was to determine how two potential abscission treatments, 1445 and 2890 mg/L ethephon, affected FDF, pre-harvest abscission, fruit quality, and ethephon residue of Thompson Seedless and Crimson Seedless grapes. Both ethephon treatments strongly induced abscission of Thompson Seedless berries causing >90% pre-harvest abscission. Lower ethephon rates, a shorter post-harvest interval, or berry retention systems such as nets, would be needed to prevent excessive pre-harvest losses. The treatments also slightly affected Thompson Seedless berry skin color, with treated fruit being darker, less uniform in color, and with a more yellow hue than non-treated fruit. Ethephon residues on Thompson Seedless grapes treated with the lower concentration of ethephon were below legal limits at harvest. Ethephon treatments also promoted abscission of Crimson Seedless berries, but pre-harvest abscission was much lower (≅49%) in Crimson Seedless compared to Thompson Seedless. Treated fruits were slightly darker than non-treated fruits, but ethephon did not affect SSC, acidity, or firmness of Crimson Seedless, and ethephon residues were below legal limits.

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Crimson Seedless is a coloured grape, gaining popularity in India for its attractive colour, bunch and berry quality with better shelf life. In cultivation of any seedless grape variety, application of GA3 at different stages is very much essential to produce good quality berries and bunches. However, this variety is highly sensitive to excess application which adversely affects bunch quality. Thus, there is a need to standardize mild dose of GA3 for rachis elongation which will help to reduce bunch compactness to a greater extent. Hence, an experiment was initiated to standardize concentration of GA3 for rachis elongation of Crimson Seedless grapes. Three different concentrations of GA3 (viz., 5 ppm, 7.5 ppm, and 10 ppm) were sprayed during pre bloom stage and compared with unsprayed control. Among different treatments, pre-bloom spray of GA3@5 ppm could produce less compact bunches with highest average bunch weight, berry weight, berry length and TSS. However, bunches sprayed with 7.5 ppm and 10 ppm GA3 could also produce good quality bunches, average berry weight with TSS. Because of severe coiling of rachis at 7.5 ppm and 10 ppm GA3 spraying, bunches were too straggly compared to spraying of 5 ppm GA3. The control bunches without GA3 produced very compact clusters with less average bunch weight, berry weight, berry diameter and berry length. [ABSTRACT FROM AUTHOR]

In order to study the effect of exogenous 5-aminolevulinic acid (ALA) on the expression of genes associated with anthocyanin biosynthesis in the transcriptome of 'Crimson Seedless' grape (Vitis vinifera) peel, sequencing technology was used to compare the transcriptomes from water and ALA treated 'Crimson Seedless' grapes. Transcriptome sequencing was performed at two periods (d5 and d15) after peel treatment. The enrichment analysis of the Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathways indicated that the metabolic pathways induced by exposure to ALA were mainly the phenylpropanoid biosynthesis, flavonoid biosynthesis, anthocyanin biosynthesis, phenylalanine metabolism, and plant hormone signal transduction pathways. In the anthocyanin synthesis pathway, ALA treatment appeared to mainly regulate the phenylalanine ammonia-lyase, cinnamate 4-hydroxylase and chalcone synthase genes in the upstream pathway of anthocyanin synthesis, and the dihydroflavonol-4-reductase gene in the downstream pathway, with the effect being most obvious at d5.This study reveals the mechanism by which exogenous ALA promotes anthocyanin synthesis at the molecular level, and lays the foundation for further study of the physiological role of ALA. [ABSTRACT FROM AUTHOR]

The ‘Crimson seedless’ grape encountered several difficulties during shelf life, including weight loss, rachis browning, and berry shattering. The effect of exogenous pectin (PE) and polyphenol alcohol (PVA) with supporting salicylic acid (SA) at different concentrations (0, 1, and 2 mM) was applied. The coating was applied to bunches for 5 min and stored at room temperature (26 ± 1 °C and RH 65 ± 3%) for 4 days. In this study, postharvest application of PE + PVA-SA can significantly reduce the cell wall degradation enzyme activities of ‘Crimson seedless’ grape during shelf life. ‘Crimson seedless’ bunches, treated with PE + PVA-SA 2 mmol L−1, had a lowered rachis browning index (RB index), weight loss (WL%), and berry shattering percentage (BS%) and preserved berry color hue angle (ho) compared to untreated bunches during shelf-life duration. Moreover, the PE + PVA-SA 2 mM improved berry firmness (BF) and removal force (BRF). It also improved the soluble solid content (SSC%), titratable acidity (TA%), and SSC: TA-ratio, for assessing berry maturity. The cellular metabolism enzyme activities (CMEAs) of the cell wall such as polygalacturonase (PG), cellulase (CEL), xylanase (XYL), and pectinase (PT) were minimized by applying PE + PVA-SA 2 mM coatings throughout storage duration. The accumulation of malondialdehyde (MDA) and cell wall damage, as well as the electrolyte leakage percentage (EL%), was reduced. PE + PVA-SA 2 mM maintained DPPH radical quenching activities and minimized O2− and H2O2 production rates. Collectively, these findings suggest that PE + PVA with the presence of SA as a coating treatment preserved ‘Crimson seedless’ bunches during shelf life. PE + PVA-SA 2 mM might be at least partially ascribed to the enhancement of bunches’ quality traits as well as inhibiting cell wall damage during the shelf-life period. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ‘Crimson seedless’ grape encountered several difficulties during shelf life, including weight loss, rachis browning, and berry shattering. The effect of exogenous pectin (PE) and polyphenol alcohol (PVA) with supporting salicylic acid (SA) at different concentrations (0, 1, and 2 mM) was applied. The coating was applied to bunches for 5 min and stored at room temperature (26 ± 1 °C and RH 65 ± 3%) for 4 days. In this study, postharvest application of PE + PVA-SA can significantly reduce the cell wall degradation enzyme activities of ‘Crimson seedless’ grape during shelf life. ‘Crimson seedless’ bunches, treated with PE + PVA-SA 2 mmol L−1, had a lowered rachis browning index (RB index), weight loss (WL%), and berry shattering percentage (BS%) and preserved berry color hue angle (ho) compared to untreated bunches during shelf-life duration. Moreover, the PE + PVA-SA 2 mM improved berry firmness (BF) and removal force (BRF). It also improved the soluble solid content (SSC%), titratable acidity (TA%), and SSC: TA-ratio, for assessing berry maturity. The cellular metabolism enzyme activities (CMEAs) of the cell wall such as polygalacturonase (PG), cellulase (CEL), xylanase (XYL), and pectinase (PT) were minimized by applying PE + PVA-SA 2 mM coatings throughout storage duration. The accumulation of malondialdehyde (MDA) and cell wall damage, as well as the electrolyte leakage percentage (EL%), was reduced. PE + PVA-SA 2 mM maintained DPPH radical quenching activities and minimized O2− and H2O2 production rates. Collectively, these findings suggest that PE + PVA with the presence of SA as a coating treatment preserved ‘Crimson seedless’ bunches during shelf life. PE + PVA-SA 2 mM might be at least partially ascribed to the enhancement of bunches’ quality traits as well as inhibiting cell wall damage during the shelf-life period.

Producing high-quality table grapes is becoming a challenge in the warmer area of the world due to the global increase in temperature, which negatively affects anthocyanin biosynthesis and other fruit quality attributes. Nanotechnology is a growing field that can be a very useful tool to improve crop productivity and sustainability. The red color is one of the major fruit quality parameters that determine table grape marketability. This study aimed to investigate the role of the zinc element in improving the marketable characteristics of Crimson seedless (Vitis vinifera L.) table grape berries i.e., color, firmness, total soluble solids and sugars; besides its role in activating PAL and SOD enzymatic systems. Additionally, this paper investigated the additive advantages of zinc when applied in nanometric form. Five concentrations of zinc oxide nanoparticles, ZnO NPs (0, 25, 50, 100 and 250 ppm), were compared to zinc oxide in mineral form at a concentration of 250 ppm to investigate their effects on the marketable characteristics of Crimson seedless grape cultivar. The treatments were applied as foliar spray on three-year-old Crimson seedless vines grafted on Richter 110 rootstock grown in one of the major table grape production area in Egypt. The experiment was arranged in completely randomized block design and each vine was sprayed with five letters of the solution. The use of the lowest concentration (25 ppm) of ZnO NPs achieved the highest significant enzyme activity (PAL and SOD). Moreover, the T.S.S, sugars and anthocyanin content in berries increased significantly in association of decreasing acidity. On the other hand, the use of a 50 ppm concentration led to an increase in fruit firmness. Collectively, our data showed that 25 ppm of zinc nanoparticles improved PAL and SOD enzymes activity, improved red coloration in table grape and was more effective than the 250 ppm zinc oxide mineral form.

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Non-destructive tools for the in situ evaluation of vine fruit quality and vineyard management can improve the market value of table grape. We proposed a new approach based on a portable fluorescence sensor to map the ripening level of Crimson Seedless table grape in five different plots in the East, Central-North and South of the Macedonia Region of Greece. The sensor provided indices of ripening and color such as SFRR and ANTHRG correlated to the chlorophyll and anthocyanin berry contents, respectively. The mean ANTHRG index was significantly different among all the plots examined due to the occurrence of different environmental conditions and/or asynchronous ripening processes. The indices presented moderate, poor in some cases, spatial variability, probably due to a significant vine-to-vine, intra-vine and intra-bunch variability. The cluster analysis was applied to the plot with the most evident spatial structure (at Kilkis). Krigged maps of the SFRR, ANTHRG and yield were classified by k-means clustering in two-zones that differed significantly in their mean values. ANTHRG and SFRR were inversely correlated over 64% of the plot. SFRR appeared to be a potential useful proxy of yield since it was directly correlated to yield over 66% of the plot. The grape color (ANTHRG) was slightly higher over the low-yield zones with respect to the high-yield zones. Our study showed that the combination of anthocyanins and chlorophyll indices detected in the field on Crimson Seedless table grape by a portable fluorescence sensor can help in defining the best harvest time and the best areas for harvesting.

Some plant growth regulators, including ethephon, can stimulate abscission of mature grape berries. The stimulation of grape berry abscission reduces fruit detachment force (FDF) and promotes the development of a dry stem scar, both of which could facilitate the production of high quality stemless fresh-cut table grapes. The objective of this research was to determine how two potential abscission treatments, 1445 and 2890 mg/L ethephon, affected FDF, pre-harvest abscission, fruit quality, and ethephon residue of Thompson Seedless and Crimson Seedless grapes. Both ethephon treatments strongly induced abscission of Thompson Seedless berries causing >90% pre-harvest abscission. Lower ethephon rates, a shorter post-harvest interval, or berry retention systems such as nets, would be needed to prevent excessive pre-harvest losses. The treatments also slightly affected Thompson Seedless berry skin color, with treated fruit being darker, less uniform in color and with a more yellow hue than non-treated fruit. Ethephon residues on Thompson Seedless grapes treated with the lower concentration of ethephon were below legal limits at harvest. Ethephon treatments also promoted abscission of Crimson Seedless berries, but dropper-harvest abscission was much lower (49%) in Crimson Seedless compared to Thompson Seedless. Treated fruit were slightly darker than non-treated fruit, but ethephon did not affect SSC, acidity, or firmness of Crimson Seedless, and ethephon residues were below legal limits.

Background and Aims The basic taste of grapes is determined by the sugars, acids and their ratio while the cultivar flavour results from its unique profile of volatile compounds. So far, the general perception is that flavour components are evenly distributed in grape berries. In the current study, the composition of TSS, titratable acidity (TA) and volatiles was examined in the stem and stylar ends of tablegrapes. Methods and Results Values of TSS were up to 2°Brix higher, and TA values were up to 1.5-fold higher in the stylar end compared with that in the stem end of the berries. Coating the berries at veraison with wax to reduce evaporation decreased TSS accumulation and the stem-end versus stylar-end difference in TSS and TA. Volatile concentration differed significantly in berry tissues in an opposite pattern being higher in the stem than in the stylar ends of the berries. Conclusions Our findings indicate that there is a substantial difference in the composition of the stem and stylar end of tablegrape berries. It is also suggested that transpiration may play a role in the uneven distribution. Significance of the Study These results are novel for tablegrapes and are likely to contribute significantly to the understanding of flavour accumulation in grapes. [ABSTRACT FROM AUTHOR]

The effect of 2-chloroethylphosphonic acid (Ethephon, in the following ETH) as abscising agent on cv . Crimson Seedless table grape was investigated by means of Fruit Detachment Force (FDF) and Fruit Drop (FD) analyses combined with a metabolomic study carried out by High Resolution Mass Spectrometry (HRMS) and Nuclear Magnetic Resonance (NMR) spectroscopy. The effectiveness of ETH as abscising agent was ascertained with ETH concentration ranging from 1.4 to 4.0 g/L in a two-year study. The ETH treatments caused berry drops higher than 40% and induced an increase of tartaric acid, procyanidin P2, terpenoid derivatives and peonidin-3-glucoside as well as a decrease of catechin and epicatechin. HRMS–NMR covariance analysis was carried out to correlate the fluctuations of tartaric acid NMR signals to those of MS peaks of the secondary metabolites affected by ETH treatments. [ABSTRACT FROM AUTHOR]

Background and Aims Cell wall changes in ripening grapes (Vitis vinifera) have been shown to involve re-modelling of pectin, xyloglucan and cellulose networks. Newer experimental techniques, such as molecular probes specific for cell wall epitopes, have yet to be extensively used in grape studies. Limited general information is available on the cell wall properties that contribute to texture differences between wine and table grapes. This study evaluates whether profiling tools can detect cell wall changes in ripening grapes from commercial vineyards. Methods Standard sugar analysis and infra-red spectroscopy were used to examine the ripening stages (green, véraison and ripe) in grapes collected from Cabernet Sauvignon and Crimson Seedless vineyards. Comprehensive microarray polymer profiling (CoMPP) analysis was performed on cyclohexanediaminetetraacetic acid (CDTA) and NaOH extracts of alcohol-insoluble residue sourced from each stage using sets of cell wall probes (mAbs and CBMs), and the datasets were analysed using multivariate software. Key Results The datasets obtained confirmed previous studies on cell wall changes known to occur during grape ripening. Probes for homogalacturonan (e.g. LM19) were enriched in the CDTA fractions of Crimson Seedless relative to Cabernet Sauvignon grapes. Probes for pectic-β-(1,4)-galactan (mAb LM5), extensin (mAb LM1) and arabinogalactan proteins (AGPs, mAb LM2) were strongly correlated with ripening. From green stage to véraison, a progressive reduction in pectic-β-(1,4)-galactan epitopes, present in both pectin-rich (CDTA) and hemicellulose-rich (NaOH) polymers, was observed. Ripening changes in AGP and extensin epitope abundance also were found during and after véraison. Conclusions Combinations of cell wall probes are able to define distinct ripening phases in grapes. Pectic-β-(1,4)-galactan epitopes decreased in abundance from green stage to véraison berries. From véraison there was an increase in abundance of significant extensin and AGP epitopes, which correlates with cell expansion events. This study provides new ripening biomarkers and changes that can be placed in the context of grape berry development. [ABSTRACT FROM PUBLISHER]

Abstract: The evolution of °Brix, protein content, polyphenoloxidase activity and peroxidase activity during the ripening of Crimson Seedless table grape was studied in three consecutive years (2006, 2007 and 2008). The total protein content was determined according to Bradford’s dye binding method, and polyphenoloxidase (PPO) and peroxidase (POD) were extracted using Triton X-114 and characterised using spectrophotometric methods. The year had a statistically significant effect on all the studied parameters and there was an interannual correlation in the evolution of protein, PPO, POD and °Brix. All the studied parameters were statistically correlated, except POD activity with protein content. Weather conditions during the ripening period had a greater effect on protein content than PPO and POD activity. [Copyright &y& Elsevier]

Abstract: Polyphenol oxidase (PPO) and peroxidase (POD) were extracted from a table grape (Crimson Seedless) using Triton X-114 and characterized using spectrophotometric methods. Both PPO and POD were activated by acid shock. However, in the presence of the anionic detergent sodium dodecil sulphate (SDS), PPO was activated whereas POD was inactivated. The enzymes were kinetically characterized and both followed Michaelis–Menten kinetics, although with different values of their kinetic parameters. The V m/K m ratio showed that Crimson Seedless grape PPO presents a similar affinity for 4-tert-butyl-catechol (TBC) whether activated by acid shock (0.018min−1) or SDS (0.023min−1). With regards to POD, the K m and V m values for 2,2′-azinobis(3-ethylbenzothiazolinesulphonic acid) (ABTS) were 0.79mM and 1.20μM/min, respectively. In the case of H2O2, the K m and V m value were 0.4mM and 0.93μM/min, respectively. PPO and POD showed similar thermostability, losing >90% of relative activity after only 5min of incubation at 78°C and 75°C, respectively. In addition, PPO´s activation energy was similar to that obtained for POD (295.5kJ/mol and 271.9kJ/mol, respectively). [Copyright &y& Elsevier]

The Vitis vinifera cultivar Crimson Seedless primarily accumulates the anthocyanin peonidin-3-glucoside. The research undertook the study of two factors which could influence the accumulation of anthocyanin in grape berry skins: ethephon application and shade. Ethephon treatment at 200ppm applied one week post-véraison significantly increased the concentration of all anthocyanins in berry skins. Peonidin-3-glucoside was found to increase most significantly in response to ethephon application, and was increased 150% compared with an untreated control. The proportion of 3-monoglucoside anthocyanins increased in response to ethephon application. A shading treatment did not affect total anthocyanin concentration in berry skins, but the anthocyanin cyanidin-3-glucoside was decreased significantly by shade. Its content was 50% of a sun-exposed control. The observed effects were found to occur at two sites at which the experiment was performed in the Hex River and Paarl regions. Colour development in the Vitis vinifera cultivar Crimson Seedless does not appear to be influenced significantly by bunch shading. The use of commercial growth regulators like ethephon exert a strong influence on anthocyanin production in grape skins of this cultivar, and are therefore a more likely solution to overcome poor colour development in its production. [ABSTRACT FROM AUTHOR]

Abstract: Table grapes are one of the most important components of the fruit diet in many countries. Grapes are consumed raw with minimal washing, and lately have also been introduced into several ready-to-eat fruit salads. Similar to other fresh produce and salads, grapes might be vulnerable to contamination in the field or during harvest by food borne pathogens. Recently, an ethanol dipping treatment was suggested as a means to prevent Botrytis decay during storage and to extend the shelf life of stored table grapes. In the present study we examined the capacity of this treatment to eradicate Escherichia coli from ‘Crimson Seedless’ grapes. Artificially contaminated grapes were exposed to increasing concentrations of ethanol by dipping bunches of grapes for 1–10min. E. coli populations were typically reduced 1–3log10cfu/g on grapes by treatment with 50% ethanol or more, although the results were highly variable. Nevertheless, examination of GFP-tagged E. coli by confocal microscopy revealed live bacteria only in water, but not in 50% ethanol-washed grapes. Staining with propidium iodide demonstrated complete killing of attached bacteria following treatment with 50% ethanol for 3min. When high E. coli inoculum was applied to peeled skin sections, a few live bacteria were still observed following an ethanol dip. These results suggest that ethanol is capable of killing E. coli cells which are attached to the skin, yet bacterial elimination is variable perhaps due to anatomical variations among the samples, which limits contact between ethanol and the attached bacteria. Ethanol treatment, beside its effect on shelf-life extension, can also contribute to minimize E. coli populations on grapes and thus enhance their safety. [Copyright &y& Elsevier]

Producing high-quality table grapes is becoming a challenge in the warmer area of the world due to the global increase in temperature, which negatively affects anthocyanin biosynthesis and other fruit quality attributes. Nanotechnology is a growing field that can be a very useful tool to improve crop productivity and sustainability. The red color is one of the major fruit quality parameters that determine table grape marketability. This study aimed to investigate the role of the zinc element in improving the marketable characteristics of Crimson seedless (Vitis vinifera L.) table grape berries i.e., color, firmness, total soluble solids and sugars; besides its role in activating PAL and SOD enzymatic systems. Additionally, this paper investigated the additive advantages of zinc when applied in nanometric form. Five concentrations of zinc oxide nanoparticles, ZnO NPs (0, 25, 50, 100 and 250 ppm), were compared to zinc oxide in mineral form at a concentration of 250 ppm to investigate their effects on the marketable characteristics of Crimson seedless grape cultivar. The treatments were applied as foliar spray on three-year-old Crimson seedless vines grafted on Richter 110 rootstock grown in one of the major table grape production area in Egypt. The experiment was arranged in completely randomized block design and each vine was sprayed with five letters of the solution. The use of the lowest concentration (25 ppm) of ZnO NPs achieved the highest significant enzyme activity (PAL and SOD). Moreover, the T.S.S, sugars and anthocyanin content in berries increased significantly in association of decreasing acidity. On the other hand, the use of a 50 ppm concentration led to an increase in fruit firmness. Collectively, our data showed that 25 ppm of zinc nanoparticles improved PAL and SOD enzymes activity, improved red coloration in table grape and was more effective than the 250 ppm zinc oxide mineral form. [ABSTRACT FROM AUTHOR]

• Twelve anthocyanins were identified and quantified in three red table grapes. • The yeast treatment actually enhance the anthocyanins content in the table grapes. • The increment in treated grapes was kept after cold storage, too. • Three anthocyanins have mainly proved to discriminate treated from control grapes. • Chemical and quality parameters of grapes were unaffected by the yeast treatment. Due to the global warming, more and more often the red-pink grape varieties grown in the Mediterranean basin reveal an insufficient accumulation of anthocyanins and thus a scarce coloration. Nowadays, this is becoming an important technological issue, which may result in the reduction of the fresh market value of table grape. This study aimed at assessing the effect of the pre-harvest treatment by specific inactivated yeasts (YE) on the qualitative parameters and anthocyanin pattern of three red table grape varieties, which typically present poor and/or incomplete coloration during warm years. An increment of anthocyanins level up to almost seven folds corresponding to an improvement of red skin appearance was observed in all the treated table grapes, which was preserved after cold storage, too. While, no significant influence on chemical composition and berry texture and dimensions was found, meaning that YE did not cause appreciable taste changes in grapes. [ABSTRACT FROM AUTHOR]

Non-destructive tools for the in situ evaluation of vine fruit quality and vineyard management can improve the market value of table grape. We proposed a new approach based on a portable fluorescence sensor to map the ripening level of Crimson Seedless table grape in five different plots in the East, Central-North and South of the Macedonia Region of Greece. The sensor provided indices of ripening and color such as SFRR and ANTHRG correlated to the chlorophyll and anthocyanin berry contents, respectively. The mean ANTHRG index was significantly different among all the plots examined due to the occurrence of different environmental conditions and/or asynchronous ripening processes. The indices presented moderate, poor in some cases, spatial variability, probably due to a significant vine-to-vine, intra-vine and intra-bunch variability. The cluster analysis was applied to the plot with the most evident spatial structure (at Kilkis). Krigged maps of the SFRR, ANTHRG and yield were classified by k-means clustering in two-zones that differed significantly in their mean values. ANTHRG and SFRR were inversely correlated over 64% of the plot. SFRR appeared to be a potential useful proxy of yield since it was directly correlated to yield over 66% of the plot. The grape color (ANTHRG) was slightly higher over the low-yield zones with respect to the high-yield zones. Our study showed that the combination of anthocyanins and chlorophyll indices detected in the field on Crimson Seedless table grape by a portable fluorescence sensor can help in defining the best harvest time and the best areas for harvesting. [ABSTRACT FROM AUTHOR]

Some red-pink table grape varieties, cultivated in warm climates, can fail in achieving the right level of anthocyanins responsible for the intense and uniform red color of berries. Nowadays, this is becoming an important technological issue in the Mediterranean area, which may result in decreasing market acceptance and potential economic value of table grape. Usually, plant growth regulators or phytohormones, such as S-ABA, can overcome this problem because they drive the accumulation of anthocyanins over the ripening season. Harpin proteins (HrP), which enhance the plant disease resistance, may be supposed to stimulate the anthocyanins biosynthesis in grape skin if applied close to veraison. Therefore, this research aimed at comparing the effect of HrP and S-ABA over the anthocyanin and color improvement of Crimson Seedless table grape grown in Southern Italy. For the first time, the exogenous treatment with HrP showed as effective as the less sustainable S-ABA one in favoring the anthocyanin accumulation, leading to peonidin-3-O-glucoside, cyanidin-3-O-glucoside, and malvidin-3-O-glucoside values up to 4 folds higher than control grapes and giving rise to a greater concentration of the more stable acylated anthocyanins. Overall, the color of berries was improved but keeping high the other quality characteristics. Unlabelled Image • Harpin proteins treatment favored the anthocyanin accumulation in grape. • Some glycosylated anthocyanins values increased up to 4 folds in treated grape. • Greater content of the more stable acylated anthocyanins was found in treated grape. • Color of berries and the overall grape quality was actually improved. • Harpin proteins as alternative to S-ABA to overcome coloration defect of red grape. [ABSTRACT FROM AUTHOR]