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1.
In grapevines, stomatal aperture decreases after a mid-morning peak during summer days. Afternoon stomatal closure increases in non-irrigated plants as water limitation progresses, which suggests the involvement of abscisic acid (ABA) in the control of stomatal aperture. The objective of this work was to study the seasonal and diurnal time-courses of CO2 assimilation rate, leaf conductance, leaf water potential +, and ABA concentration in xylem sap, leaves, flowers and berries in non-irrigated field-grown Tempranillo grapevines throughout reproductive development. Leaf decreased throughout fruit development because water availability decreased towards the end of the reproductive cycle. CO2 assimilation rate, leaf conductance and xylem ABA concentration also decreased during the course of the growing season. Combining all measurements xylem ABA was either not correlated, or only slightly correlated, with leaf water status + and daily leaf conductance, respectively. This lack of relationship indicates that xylem ABA during fruit ripening had functions other than provision of a non-hydraulic signal. On a seasonal basis, xylem ABA concentration measured in non-irrigated grapevines was well related to berry ABA concentration, especially at the end of fruit development (veraison and harvest).  相似文献   

2.
Phenolic profile, antioxidant activity, and color parameters of Polish wines, produced from the multispecies hybrid and Vitis vinifera L. grapes were analyzed. A principal component analysis was applied, in order to differentiate the investigated wines in terms of content of phenolic compounds. The white wines turned out to be similar to each other in terms of color parameters and the results of principal component analysis, while the red wines strongly differed in this respect. However, the white wine produced from the multispecies hybrid grapes contained a higher level of phenolic acids and flavonoids, as compared to the white wines obtained from the hybrid cultivars. Out of the red wines, Rondo wine, produced from the multispecies hybrid grapevine was the richest in total phenolic and phenolic acids content. Caffeic acid and quercetin were the predominant phenolics in majority of the wines tested.  相似文献   

3.
以红地球葡萄为研究试材,采用(0、50、100和200 μmol/L)茉莉酸甲酯(Methyl Jasmonate,MeJA)在膨大期、转色期和采收前2 d(预收期)喷施处理红提葡萄果实,在0±1 ℃条件下贮藏。结果表明,在离体条件下,MeJA对灰葡萄孢菌的菌体生长量和菌落直径无显著差异作用(p<0.05),较高浓度对菌体生长具有一定的抑制作用。在贮藏期间,MeJA可以显著抑制葡萄果实采后腐烂的发生、延缓果实硬度的下降和提高果实可溶性固形物的含量,维持可滴定酸含量。100 μmol/L MeJA处理组优于其他组,在贮藏50 d时,CK组发病率为86.09%,是MeJA处理组的1.53倍,MeJA处理组的可溶性固形物含量为17.3%,可滴定酸含量为0.675%。40 d时MeJA处理组的硬度为7.5 N,是CK组的1.59倍,CHI活性为370.12 U/g,20 d时MeJA处理组GLU活性为105.86 U/g,是CK组的1.11倍。10 d时MeJA处理组PAL和POD活性为2.43 U/g和0.506 U/g,是CK组的1.18和1.58倍。MeJA采前喷施能有效诱导果实PAL、POD、CHI和GLU酶活性的上升,表明MeJA采前喷施处理能够通过诱导提高葡萄实酶活性来提高果实采后抗病性,提高葡萄贮藏效果,减少果实采后腐烂的发生。  相似文献   

4.
Polyphenol oxidase (PPO) was extracted from Sultaniye grapes grown in Turkey, and its characteristics in terms of pH and temperature optima, thermal inactivation, kinetic parameters and potency of some PPO inhibitors were studied. Optimum pH and temperature for grape PPO were found to be 3.4 and 30 °C, using catechol as substrate. Km and Vmax values were found to be 44.5 ± 5.47 mm and 0.695 ± 0.0353 OD410 min?1, respectively. Four inhibitors were tested in this study and the most potent inhibitor was sodium metabisulphite, followed by ascorbic acid. From the thermal inactivation studies in the range of 65–80 °C, the half‐life values of the enzyme ranged between 2.6 and 49.5 min. Activation energy (Ea) and Z values were calculated to be 208.5 kJ mol?1 (r2 = 0.9544) and 10.95 °C (r2 = 0.9517), respectively.  相似文献   

5.
Free and glycosidically bound flavor compounds of a white wine from cv. Emir were analyzed by GC-MS, and 75 compounds were identified. The wine was high in volatile phenols. Skin-contact with the juice before fermentation increased amounts of free and glycosidically bound flavor compounds. Quantities of certain compounds were significantly different between control and skin-contact wines.  相似文献   

6.
7.
A chitinase gene (Chi3K) was cloned from the genomic DNA of Vitis vinifera cv. Koshu. The structural gene comprised 891 by without introns and encoded 297 amino acids. The Chi3K product showed high similarity to the class III chitinase of V. vinifera cv. Pinot noir. Chi3K was expressed using a bacterial expression vector for purification and enzymatic characterization of its gene product. The recombinant chitinase exhibited hydrolytic activity toward glycol chitin and its optimum pH was 4.0. It also inhibited the growth of Botrytis cinerea, which causes grey mold disease in grapes.  相似文献   

8.
自动质谱图解卷积和鉴定系统(AMDIS)是美国标准化委员会推出的一款辅助气质数据定性分析的软件,利用该软件可有效的克服GC-MS定性分析中基质效应和共洗脱效应的干扰,增加解谱的准确性和可靠性.本研究将GC-MS检测技术和AMDIS辅助解谱相结合,从雷司令葡萄果实中鉴定出15种降异戊二烯类物质,他们多数以游离态形式存在,在果实发育早期或转色前期含量最高;此外还检测到4种结合态该类化合物.在成熟果实中,β-大马士酮和β -紫罗兰酮含量远高于其感觉阈值,呈现煤油味的TDN也略高于其阈值.该研究为AMDIS技术在果实香气成分分析中的推广应用提供了参考.  相似文献   

9.
Anatomical studies on the movement of a xylem tracer dye were combined with functional studies on changes in grape berry volume during final stages of berry ripening to gauge xylem effectiveness. Movement of a xylem tracer dye into pre-veraison fruit was compared with movement into post-veraison fruit by feeding a solution of acid fuchsin to excised shoots with bunches still attached, and then sectioning fruit for photo-microscopy. Those comparisons confirmed published studies showing an apparent blockage to dye movement along major vessels within the brush tissue of post-veraison fruit. However, our functional approach yielded a different impression of vascular activity. A continuation of xylem transport in ripening fruit was inferred from comparisons of berry volume where pedicels were either girdled (phloem interrupted, but xylem intact) or excised (both phloem and xylem interrupted). Volume changes in manipulated berries were compared with immediately adjacent intact control berries within the same bunch. Control fruit lost volume subsequent to 78 days after flowering (DAF) while manipulated fruit lost volume from the first day of treatment at 67 DAF. By harvest time at 95 DAF, both control fruit and girdled fruit had fallen to 91% and excised fruit to 46% of maximum volumes recorded around 78 DAF. Berry volume loss in girdled fruit was further enhanced by deficit irrigation. We conclude that xylem flow into those Shiraz berries must have continued beyond veraison despite dye evidence of a vessel blockage within the brush region of analogous post-veraison fruit.  相似文献   

10.
Polyphenols extracted from the seeds of Vitis vinifera L. cv. Shiraz berries were monitored during berry development. Initially seeds were green, plump and had pliable seed coats, but beginning at veraison the seeds browned in colour, became desiccated and the seed coats hardened. Isolated polyphenols consisted of flavan-3-of monomers ((+)-catechin, (-)-epicatechin and (-)-epicatechin-3-O-gallate) and procyanidins. The procyanidins were maximal in the 3 weeks prior to veraison, increasing little during this period. The amounts of flavan-3-ol monomers increased 5-fold during this same period of time, indicating that the procyanidins and the flavan-3-ol monomers accumulate at different stages. Beginning at veraison, amounts of all polyphenols declined and changed in composition. The decrease in amount followed second-order kinetics. Polyphenol changes after veraison could be explained by oxidation and therefore, electron paramagnetic resonance (EPR) spectroscopy was used to follow the potential development of radical species in the developing seeds. Spectra consistent with a phenoxyl radical were observed in the developing seeds. The concentration of radicals remained low until veraison but then increased, reaching a maximum three weeks later, declining slowly thereafter. Changes in radical intensity together with other documented changes in the seed are consistent with an oxidative event occurring during fruit ripening.  相似文献   

11.
The impact of water availability on the yield and on the chemical composition in the skins of cv Tempranillo grapes at different phases of berry growth was studied over a 2 year period by determining changes in berry weight, °Brix, titratable acidity, pH and different phenolic compounds. The evolution of phenolic compounds during berry growth followed similar patterns to those reported by previous investigators. Over the 2 year study, concentrations of total phenols and total tannins in the skins were always higher for the non-irrigated than for the irrigated vines, though the differences were not significant on some sampling dates. Total anthocyanin concentrations in 1992 were significantly higher in the non-irrigated than in the irrigated grapes, except at véraison and harvest. In contrast, in 1993, concentrations were higher in the non-irrigated grapes on the first three sampling dates and in the irrigated grapes on the last three sampling dates, but with significant differences only on day 136 after budbreak. In the first year, anthocyanin concentrations for the non-irrigated grapes were higher than for the irrigated grapes, except at harvest, though the differences at harvest were not significant. However, in the second year, concentrations in the berries from the irrigated vines were significantly higher on most sampling dates. In both years, concentrations of the five anthocyanins at harvest were higher for the irrigated treatment, the treatment that produced higher berry weights and crop yields. © 2001 Society of Chemical Industry  相似文献   

12.
为研究赤霞珠葡萄果实发育过程中不同组织(果皮、果肉和种子)内源激素的含量变化及其与果实成熟的关系,用高效液相色谱-质谱联用技术测定果实发育过程中果皮、果肉以及种子中脱落酸(abscisic acid,ABA)、生长素(indole acetic acid,IAA)、赤霉素(gibberellin A_3,GA_3)、茉莉酸(jasmonic acid,JA)和水杨酸(salicylic acid,SA)的含量。结果发现,在葡萄果实生长发育过程中,葡萄果皮和果皮中ABA含量呈双S型变化,花后20 d左右,ABA含量较高,随着果实膨大开始下降,随后开始上升,至转色中期达到最大值,随着果实的成熟缓慢下降;果皮、果肉和种子中GA_3含量均是从果实膨大期开始上升,膨大后期下降,随后在转色初期又开始上升,随后下降;JA含量的变化与GA_3类似;果皮和果肉中IAA含量首先略微下降,在果实快速生长期迅速上升,并达到峰值,随着果实进入转色期,含量逐渐下降并保持稳定,果实膨大期之前,种子中IAA含量较高,随着果实膨大降低,并维持在较低水平,SA含量的变化与IAA类似。结论:ABA、GA_3、JA含量与赤霞珠果实成熟有关,IAA、GA_3、SA、JA含量与赤霞珠果实生长有关。  相似文献   

13.
Fruit ripeness has an influence on the phenolic and aromatic composition of grapes and musts and, therefore, on the sensorial characteristics of the resulting wine. The aim of the work described here was to assess the influence of the harvest date on the analytical composition of the musts and wines from the Vitis vinifera cv. Tempranillo grape grown in a warm climate. A hydroalcoholic medium was employed to extract the musts and simulate a traditional maceration process. Phenolic compounds were analysed by colorimetric methods and aroma compounds by gas chromatography/mass-spectrometry. Furthermore, the wines were tested by a sensory panel. A good correlation was obtained between the parameters measured in the must and in the corresponding wine, as well as in the scores recorded in the sensory analysis. In summary, grape ripening was found to have a marked influence on the wine composition and it was possible to establish the key parameters that need to be measured in the must during ripening to identify the optimal harvest date to obtain the best quality wine.  相似文献   

14.
Polyphenol oxidase (PPO) was extracted from Emir grapes grown in Turkey and its characteristics in terms of pH and temperature optima, thermal inactivation, kinetic parameters and potency of some PPO inhibitors were studied. The optimum pH and temperature for grape PPO were found to be 4.2 and 25 °C respectively using catechol as substrate. Km and Vmax values were found to be 25.1 ± 2.72 mmol L−1 and 0.925 ± 0.04 OD410 min−1 respectively. Of the inhibitors tested, the most potent was sodium metabisulfite, followed by ascorbic acid. The thermal inactivation curve was biphasic. Activation energy (Ea) and Z values were calculated as 251.4 kJ mol−1 (r2 = 0.996) and 8.92 °C (r2 = 0.993) respectively. Copyright © 2006 Society of Chemical Industry  相似文献   

15.
BACKGROUND: The present article reports the anthocyanin content in the berry skin and wine of the Italian red grape cultivar Aglianico (clone VCR11 grafted onto 1103 Paulsen), one of the most ancient vines and famous for its deep‐red colour. Anthocyanins were extracted from frozen berry skin in an acidified methanol solution. The extraction mixtures, monitored for 120 h, were analysed by high‐performance liquid chromatography. RESULTS: The extraction from berry skin of delphinidin, petunidin and malvidin appeared to be a time‐independent process, whereas the concentration of peonidin increased linearly with time. Peonidin‐O‐acetyl‐glucoside was transferred from skin more slowly than petunidin‐O‐acetyl‐glucoside and malvidin‐O‐acetyl‐glucoside. The anthocyanin composition of the resulting wine showed that the total anthocyanin content was about one‐tenth of the corresponding berry skin content. The ratio acetyl/coumaroyl anthocyanins in the wine was sharply higher than the value in berry skin (0.85 and 0.10, respectively), indicating an enrichment of acetyl derivatives in the wine. CONCLUSION: Levels of single anthocyanins in wine were not always correlated with those detected in grapes, as they were affected by winemaking. The high values of some anthocyanins in Aglianico wine could ameliorate its quality, increasing the chromatic properties, aging stability and product acceptance. Copyright © 2011 Society of Chemical Industry  相似文献   

16.
Skin maceration is an essential winemaking technique that affects sensory properties and aroma of red wines. The aim of this study was to investigate aroma profiles of red wines made from cv. Karao?lan, a grape variety grown in Arapgir (Malatya, Turkey) and the effect of maceration time (5, 10, and 15 d) on free and bound aroma compounds and sensory properties. Three maceration times were applied in durations of 5, 10, and 15 d. Free and glycosidically bound aroma compounds were analyzed using gas chromatography‐mass spectrometry (GC‐MS) in Karao?lan wines, and the effect of different maceration times on aroma composition were evaluated. Results indicate that extended maceration time significantly influenced the aroma composition of wines both qualitatively and quantitatively. A total of 59 free and 22 bound aroma compounds were identified in the final wines. The maximum of free aroma content was achieved with 5 d of maceration, while 15 d of maceration gave the highest amount of glycosidically bound aroma compounds. From sensorial point of view, the wine produced with 10 d of maceration had the best panel score compared to wines with 5 and 15 d of maceration. This is the first study referring to the composition of aroma compounds of red wines made from cv. Karao?lan. It was concluded that this cultivar resulted in a good quality wine in terms of bound and free aroma compounds. This information of vinification practices that influence the chemical properties of wine is useful for grape growers and winemakers.  相似文献   

17.
袋控缓释肥在巨峰葡萄上的应用效果研究   总被引:1,自引:0,他引:1  
以巨峰葡萄为试材,研究袋控缓释肥对其产量和品质的影响。结果表明:使用缓释肥较常规施肥穗重增加54g,增产5246.1kg/hm2,增幅达25.70%;新梢粗度和叶面积分别比对照增加10.2%和51.32%;可溶性固形物含量和糖酸比分别比对照增加0.9%和3.52,且裂果率降低21%;从花期到成熟期,叶柄中N、P、K含量相近,或有不同程度的提高,且生产成本差异不显著。  相似文献   

18.
Background and Aims: The purpose of this study was to gain a quantitative understanding of environmental effects on the formation of yield potential; it is critical that the timing of anlagen initiation and differentiation in latent buds is defined for economically important Vitis vinifera L. cultivars in a range of environments. Methods and Results: This study combined scanning electron microscopy with light microscopy to compare the timing and extent of inflorescence primordia (IP) initiation and differentiation (branching) in primary latent buds of Chardonnay vines grown in a hot (mean January temperature (MJT) 22.3°C) and a cool (MJT 18.1°C) climate. Initiation of anlagen (uncommitted primordia) in dormant buds at node 4 commenced 4 weeks after budburst (BB) in the hot climate and 6 weeks after BB in the cool climate. Subsequent differentiation of anlagen was first observed 6 and 9 weeks after BB in the hot and cool climate, respectively. Conclusions: The extent of IP differentiation varied with climate, with hot climate buds at modified Eichorn and Lorenz scale (E‐L) ( Coombe 1995 ) stage 33 being more advanced, larger and exhibiting more widespread secondary branching than cool climate buds. Significance of the Study: This research provides new insights into the timing and extent of reproductive development in Australia's most important white grape cultivar, Chardonnay, thereby having implications for strategic management and forecasting potential yield.  相似文献   

19.
20.
This work reports the adsorption of anthocyanins by the cell walls of different strains of Saccharomyces during the production of red wine from Vitis vinifera L. cv Graciano grapes. The anthocyanin derivative contents of the yeast cell walls were substantially different to those of their corresponding wines. Cinnamoyl derivatives (6-p-coumaroyl and 6-caffeoyl) were strongly adsorbed while vitisins (adducts of pyruvic acid and acetaldehyde) were weakly adsorbed. The mean total anthocyanin concentration of the wines was 507.64 mg L?1 with the following distribution: 3-glucosides (3G), 82.2%; vitisins, 0.97%; 6-acetyl derivatives, 7.44%; 6-caffeoyl derivatives, 1.81%; and 6-p-coumaroyl derivatives, 7.54%. A mean of 18.57 mg of anthocyanins were adsorbed by the lees corresponding to 1 L of wine; this quantity was distributed: 3G, 52.60%; vitisins, 0.15%; 6-acetyl derivatives, 4.06%; 6-caffeoyl derivatives, 6.61%; and 6-p-coumaroyl derivatives, 36.58%. Large differences were seen between the different yeast strains examined with respect to the quantities of anthocyanins adsorbed. The mean adsorption percentage was 3.67%, but this varied between 1.60% (strain 3VA) and 5.85% (strain 9CV). The adsorption percentage of 6-p-coumaroyl derivates for strain 3VA (7.61%) was fourfold less than that of 9CV (28.37%). Strains 2EV and 3VA showed no vitisin adsorption.  相似文献   

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