Shiraz berry size in relation to seed number and implications for juice and wine composition

This study was conducted over three seasons on irrigated Shiraz grapevines growing in a warm climate. We addressed the question of whether differences in berry size (within a population of berries from minimally pruned, own‐rooted or Ramsey‐grafted vines), would lead to differences in juice composition, wine composition or wine sensory score. Predictably, berry mass was found to increase with seed number, but berries in the smallest mass categories (0.3–0.7 g) still had similar juice soluble solids and pH; and similar concentrations of K+, tartaric acid and malic acid, compared with larger berries (1.4–2.0 g). Only for the very smallest mass category (0.3–0.55 g) was there any indication of better colour density (both for own‐rooted and Ramsey‐grafted vines) or higher anthocyanin concentration (for own‐rooted vines) compared with larger berries (1.4–2.0 g). Concentrations of tartaric acid and K+ in berry skins were highest in the smallest berry mass categories (0.3–0.7 g) and decreased with increasing berry mass (up to 1.4–2.0 g). A strong correlation (R²= 0.85) between skin tartaric acid and K+ concentrations was observed across that range. Small‐scale wine lots based on small berries (0.8–0.9 g) versus large berries (1.2–1.3 g) showed no differences in measures such as soluble solids, total acids or pH of juice; nor any differences in pH, total acids, K+, tartrate, malate, spectral characteristics or sensory score of corresponding wines. Moreover, small berries had a similar skin to fruit ratio, and a similar juice yield, compared to large berries. However, when measured post‐fermentation, the ratio of seed weight to skin weight was higher for small berries. The mass range of berries used here for small‐scale winemaking (i.e. from 0.8–0.9 g up to 1.2–1.3 g), covered the range of Shiraz berry mass typically found in irrigated vineyards (from 0.8 to 1.5 g), and thus confirms the relevance of present outcomes to practical winemaking. Finally, our data for variation in juice and wine composition as a function of berry size, showed consistent trends for all seasons, and thus implies that reported instances of improved wine quality from small berries (often associated with certain pruning treatments or deficit irrigation strategies), are more likely due to treatment effects that lead to small fruit, rather than to intrinsic developmental differences between large and small berries.     

Rootstock and salinity effects on rates of berry maturation, ion accumulation and colour development in Shiraz grapes

Shiraz grapevines on either their own roots, or on the rootstocks Ramsey, 1103 Paulsen, 140 Ruggeri or 101–14, were grown at two separate sites within the Murray‐Darling viticultural region with similar irrigation regimes but with an irrigation water salinity of either 0.43 dS/m (low salinity site) or 2.3 dS/m (high salinity site). Rootstock effects on grape berry development, ion concentrations, soluble solids and acidity were followed during one season. Wines were also made and compared using spectral analysis and sensory evaluation. Rootstock effects that were common across both sites were (1) a close relationship between K+and soluble solids accumulation in developing grape berries which commenced at the onset of veraison and was indicative of a link between K+and sucrose transport in the phloem, and (2), higher wine K+, pH and colour hue for all rootstocks with one exception, namely 101–14 at high salinity where 101–14 responded similarly to own roots. Juice K+, pH and loss of K+from juice during winemaking were highest for grapes from the high salinity site. Mean berry weight was smaller and the range in berry size across rootstocks was narrower at the saline site. The narrower range in berry sizes may have contributed to fewer rootstock effects on wine spectral characteristics at high salinity. There was no effect of rootstock on CO₂ assimilation rate or stomatal conductance at either site, although intrinsic leaf‐based water‐use efficiency measured as A/g was 50% higher at the saline site. All treatments exhibited berry shrivel at maturity, but the extent was smaller at high salinity. Slower development of berry colour during veraison was observed on some rootstocks, for example 101–14, and while unrelated to canopy size per se, a higher leaf‐to‐fruit ratio for 101–14 may have been a factor. Slower berry colour development during veraison had no bearing on the colour density of wine made from the harvested grapes.     

Rootstock effects on salt tolerance of irrigated field-grown grapevines (Vitis vinifera L. cv. Sultana) 2. Ion concentrations in leaves and juice

Field vines of cv. Sultana, grown either on their own roots, or grafted to a range of rootstocks, were drip‐irrigated at three salinity levels (0.40, 1.75 and 3.50 dS/m) over a five‐year period. Rootstocks comprised Ramsey, 1103 Paulsen, J17‐69 and 4 hybrids (designated R1, R2, R3 and R4) derived from parentage involving Vitis champini, V. berlandieri and V. vinifera. Concentrations of Cl^‐, Na+, K+, Ca²⁺ and Mg²⁺ were measured in petioles at flowering, and in laminae and grape juice at harvest, in each year of the trial. Vines on all rootstocks accumulated less chloride in either petioles at flowering or in laminae and juice at harvest compared with vines on own roots at all salinity treatments. By inference, all rootstocks behaved as chloride excluders relative to the roots of own‐rooted vines. 1103 Paulsen was the best chloride excluder based on lowest concentrations of accumulated Cl^‐ in petioles, laminae and grape juice at high salinity. Sultana on R3 rootstock at high salinity accumulated more Na+ in both laminae and grape juice (at harvest) than did Sultana on own roots or on any of the other rootstocks. Laminae K+ at harvest time was reduced at high salinity in Sultana on own roots and on all rootstocks. Concentrations of both Cl^‐ and Na+ in petioles at flowering and in laminae and grape juice at harvest showed no significant correlation with either yield (as kg of fresh grapes per vine) or vigour (as measured by fresh weight of one‐year‐old pruning wood per vine) for any salinity treatment. There was however, a strong positive correlation between yield and the subsequent weight of one‐year‐old pruning wood for all salinity treatments. There was also a negative correlation between Na+ concentrations in petioles at flowering and the subsequent weight of one year‐old‐pruning wood from the 0.40 dS/m treatment. Similar negative correlations were found between Na+ concentration in both laminae and grape juice at harvest time, and the subsequent weight of one‐year‐old pruning wood from the 0.40 dS/m treatment (but not from either the 1.75 or 3.50 dS/m treatments). Based on these findings and those from Walker et al. 2002a we conclude that a high innate vigour of a rootstock combined with moderate to high chloride and sodium exclusion ability represents the best combination for salt tolerance in Sultana grapevines as measured by yield at moderate to high salinity.     

Effects of novel hybrid and traditional rootstocks on vigour and yield components of Shiraz grapevines

Background and Aims:  The influence of grapevine rootstocks on vine vigour and crop yield is recognized as an integral part of viticultural management. However, the genetic potential of Vitis species rootstock hybrids for vigour and yield control is not fully exploited in Australian viticulture. The effect of 55 novel inter- and intra-species hybrids and five traditional hybrid rootstock cultivars on winter pruning weight, berry size and fruit yield of grafted Shiraz vines is presented. The genetic predictions that resulted from this analysis were used to illustrate how rootstocks that best perform for a combination of traits may be selected.
Methods and Results:  The use of linear mixed models and residual maximum likelihood procedures took into account repeated measures and spatial variation within a large field trial (720 vines). Over 6 years of assessment, variation of up to 93.9% in winter pruning weight, 81.9% in fruit yield and 21.0% in berry weight between rootstocks was estimated.
Conclusions:  The effect of rootstock genotype accounted for marked differences in conferred pruning weight, berry weight and fruit yield from trial averages. Comparison of statistical analysis techniques illustrated that the choice of such techniques may influence the outcome of genetic selection from field trial data.
Significance of the Study:  Such quantification of the variation between vines in vigour, fruit yield and berry size due to rootstock genotype provides a framework for selection of well-performing genotypes for inclusion in advanced generations of the CSIRO vine rootstock breeding program.     

Yield-salinity relationships of different grapevine (Vitis vinifera L.) scion-rootstock combinations

Three data sets derived from 5– or 6‐year field experiments at Merbein (Victoria), Dareton (New South Wales) and Loxton (South Australia) were used to assess the relationship between yield of own‐rooted or grafted grapevines and electrical conductivity of the saturated soil paste extract (ECe). This involved a non‐linear least squares fit method to determine the threshold of ECe at which yield begins to decline and the slope of the yield reduction with increasing ECe above that threshold. Threshold and slope are the two key parameters in this piece wise linear model of grapevine response to salinity. The soil ECe values were integrated to take account of both spatial and temporal variation in soil salinity within the profile. The ECe threshold for own‐rooted Sultana at Merbein in the Sunraysia region was found to be 2.3 0.2 dS/m and the slope of yield reduction above the threshold was 8.9 1.2 % per 1 dS/m increase in soil ECe. At Dareton, a similar threshold of 2.1 0.3 dS/m was found for own‐rooted Sultana, however the higher slope of the yield reduction (15.0 2.0 %) relative to the same vines at Merbein may have been related to the higher sodium adsorption ratio (SAR) in irrigation water and its impacts on soil physical properties, especially in that part of the vineyard with a heavier soil type. The rootstock Ramsey resulted in a threshold of 3.3 0.2 dS/m and slope of 5.7 0.4% with the scion Colombard at Loxton, indicating a more tolerant combination of scion‐rootstock to salinity. The rootstocks 1103 Paulsen and R2 with Sultana as scion were the most salt tolerant, with no discernible yield reduction until ECe exceeded about 4 dS/m. Of four other rootstocks with Sultana as scion, compared with own‐rooted Sultana, J17–69, and R4 had similar threshold values (2.3 0.2 and 2.5 0.2 dS/m) and slopes of yield reduction (10.1 1.9 % and 8.0 0.5 %, respectively), while R1 had a similar threshold of 1.8 0.2 dS/m but a lower slope of yield reduction (4.3 0.9 %) than Sultana on own roots and R3, J17–69, R1 and R4 rootstocks. Comparatively, R3 rootstock responded differently by way of a higher threshold of 3.0 0.2 dS/m than own‐rooted Sultana and J17–69 and R1 rootstocks and a higher slope of yield reduction of 12.4 1.0 % relative to Sultana on own roots and R4 and R1 rootstocks. Based on our long‐term studies of yield‐salinity relationships on contrasting sites, the pre‐eminence of certain rootstocks in conferring tolerance to soil salinity has been confirmed. Ramsey, 1103 Paulsen, and a new hybrid designated here as R3 were generally outstanding, with Ramsey varying only slightly in its comparative effectiveness when grafted to different scion varieties. An overall interaction between scion variety and rootstock genotype was thus evident in the form of yield‐salinity relationships.     

Effect of reduced irrigation on growth,yield, ripening rates and water relations of Chardonnay vines grafted to five rootstocks

Background and Aims: In the first decade of the 21st century, drought within the Murray–Darling Basin has reduced the amount of water available for irrigation. We investigated whether the response of vines to reduced irrigation was modified by rootstock. Methods and Results: Reduced irrigation (5 versus 8 ML/(ha·year)) was applied to Chardonnay vines grafted to five rootstocks (Ramsey, 140 Ruggeri, 1103 Paulsen, 110 Richter and K51‐40) for four seasons. It decreased the yield from 29.3 to 26.7 kg/vine, and increased the irrigation water use index (IWUI) from 4.7 to 6.6 t/(ha·ML), but gains in this index declined as the trial progressed. The values of mid‐afternoon leaf water potential were not affected by reduced irrigation, but leaf CO₂ assimilation declined from 13.1 to 11.7 µmol/(m²·s). These effects were independent of rootstock. Reduced irrigation did not increase soil salinity (ECe) or vine tissue Na and Cl concentrations. Vines on Ramsey and 1103 Paulsen rootstocks had higher yields, 32.2 and 30.0 kg/vine, respectively, and the highest IWUIs, 5.9 and 5.5 t/(ha·ML). In two of the three seasons, reducing irrigation did not affect the rates of ripening (°Brix/growing degree days) excepting vines on 1103 Paulsen. Ripening rates varied by 1.5‐fold between seasons. Conclusion: The yield and growth responses of Chardonnay vines to a 35% reduction in irrigation were not modified by rootstock. Significance of the Study: Reducing irrigation did not lead to a build‐up of soil salts. The response of vines to reduced irrigation on rootstocks rated as having good drought tolerance was the same as that for vines on a rootstock rated as having poor drought tolerance.     

Potassium concentration and pH inter‐relationships in grape juice and wine of Chardonnay and Shiraz from a range of rootstocks in different environments

Background and Aims: pH adjustment during winemaking is a significant cost to the Australian wine industry. This study addresses potassium (K⁺) concentration and pH inter‐relationships in grape juice and wine of Chardonnay and Shiraz. Methods and Results: Chardonnay and Shiraz on own roots, and on Ramsey, 1103 Paulsen, 140 Ruggeri, K51‐40, Schwarzmann, 101‐14, Rupestris St. George and 1202 Couderc were compared at Koorlong and Merbein (Victoria), and Padthaway, Nuriootpa and Rowland Flat (South Australia). Petiole K⁺ concentrations at flowering were a poor indicator of grape juice and wine K⁺ concentrations. The concentration of H⁺ ions in grape juice and wine decreased as K⁺ concentrations increased resulting in increased pH. The relationship between H⁺ and K⁺ concentrations was linear for Chardonnay but exponential for Shiraz, where K⁺ concentrations were higher. Wine K⁺ and grape juice K⁺ concentrations exhibited a positive linear relationship, with slope for Chardonnay about half that for Shiraz, indicating a net loss of K⁺ between grape juice and wine of 58% for Chardonnay and 13% for Shiraz. Conclusions: The study has linked higher wine pH to both higher juice soluble solids and K⁺, and to poorer wine colour hue. Loss of K⁺ during fermentation and cold stabilisation appeared higher for Chardonnay than for Shiraz. Significance of the Study: Rootstocks that lead to lower K⁺ concentrations and pH in grape juice and wine are identified. Differences in the K⁺ concentration dynamics between grape juice and wine of Chardonnay and Shiraz are described and quantified.     

Interaction of rootstock and applied water amounts at various fractions of estimated evapotranspiration (ETc) on productivity of Cabernet Sauvignon

Background and Aims: It is commonly thought that grapevine rootstocks vary in their tolerance to drought. This study examined the interaction between various applied water amounts and productivity of Cabernet Sauvignon grafted onto five rootstocks. Methods and Results: The commercial vineyard used in this study was located along the central coast of California. The rootstocks used were Teleki 5C, 110 Ricter, 140 Ruggeri, 1103 Paulson and Freedom. Irrigation amounts ranged from 0.25 up to 1.25 of estimated vineyard evapotranspiration. Midday leaf water potential (Ψ_l), was significantly affected by irrigation treatment but not by rootstock. There was a significant effect of irrigation treatment and rootstock on berry weight, number of bunches per vine and yield but no interaction between those two factors. The rootstock 5C had the lowest yield compared with the other rootstocks. Yield at the 0.25 irrigation level was approximately 62% of the yield at the 1.25 irrigation level across rootstocks. Irrigation treatment was the only factor that significantly affected soluble solids in the fruit. There was a significant interaction between rootstock and irrigation amount on pruning weights. Berry weight, yield and pruning weights were linearly correlated with midday Ψ_l across rootstock and year. Conclusions: The results indicate that the rootstocks producing greater yields at the highest applied water amounts also produced greater yields when deficit irrigated. Significance of the Study: Under both stressed and non-stressed conditions, the rootstocks with the highest yield were those with the greatest number of bunches.     

酿酒葡萄嫁接育苗中砧穗组合愈合性与生根率的研究

本文对5个优良酿酒葡萄品种和4种砧木嫁接组合的愈合性及生根率进行研究,结果发现,砧木品种101-14对试验的5个葡萄品种均具有较好的愈合性和生根率,是嫁接生产苗木的首选砧木品种,其次是砧木品种5BB,而SO4的表现相对较差。     

葡萄不同砧穗组合的营养特征分析

本试验以5种葡萄嫁接植株为研究对象,分析了植株的N、P、K含量和贮藏营养水平,以探讨砧木根系对葡萄营养特性的影响。结果表明:不论什么嫁接品种,枝条和根系中的N、P、K含量,可溶性糖和淀粉含量均以嫁接沙地葡萄-冬葡萄系列砧木110R和1103P的植株较高,嫁接河岸葡萄-冬葡萄系列砧木420A、SO4,以及河岸葡萄-沙地葡萄系列砧木3309C的植株较低。生长季节各组合叶柄N素含量在0.9%～1.1%之间,处于偏低水平,以桑娇维赛/1103P和玛瓦斯亚/110R的叶柄N较高,玛瓦斯亚/420A的较低;各组合叶柄P含量在0.08%～0.12%之间,处于丰足水平,以M/3309C的较高,S/SO4的偏低;不同砧穗组合K营养水平差异显著,变化于0.65%～0.23%之间,以M/110R较高,S/SO4较低,但均处于不足范围,需要补K。     

Reduced irrigation and rootstock effects on vegetative growth,yield and its components,and leaf physiological responses of Shiraz

Background and Aims: The study investigated whether rootstocks can modify grapevine responses to reduced irrigation. Methods and Results: Drip-irrigated Shiraz vines on eight rootstocks were subjected to industry standard and 30% reduced irrigation regimes over four seasons. Reducing irrigation decreased pruning weights and yield, but did not consistently affect irrigation water use index (IWUI). It increased leaf Δ¹³C. Reduced irrigation and elevated vapour pressure deficit (VPD) were associated with decreases in leaf water potential (ψ_l), leaf stomatal conductance and assimilation rate. Reducing irrigation raised leaf transpiration efficiency, whereas elevated VPD lowered it. These effects of reduced irrigation were independent of rootstock. Vines grafted to 101-14 had a higher ψ_l and achieved the highest yield and IWUI. The yields of vines grafted to Ramsey, Schwarzmann and 140 Ruggeri were also high. Vines grafted to 101-14, Ramsey and 1103 Paulsen had the higher rates of leaf assimilation. Rootstock did not affect Δ¹³C. Conclusion: The gain in leaf transpiration efficiency caused by reducing irrigation was not associated with a gain in IWUI. Rootstocks 101-14, Ramsey, Schwarzmann and 140 Ruggeri achieved higher yields and IWUI under both standard and reduced irrigation regimes. Significance of the Study: Among grafted vines growing on saline soil but receiving non-saline irrigation water and subject to a 30% reduction in irrigation, the yield responses of vines grafted on rootstocks rated as having good drought tolerance were the same as those of vines grafted on rootstocks rated as having poor drought tolerance.     

Rootstock effects on salt tolerance of irrigated field-grown grapevines (Vitis vinifera L. cv. Sultana).: 1. Yield and vigour inter-relationships

Vegetative growth and yield of grapevines grown in the field on their own roots or grafted to a range of rootstocks were investigated under drip irrigation with water of three salinity levels (0.40, 1.75 and 3.50 dS/m) over a five‐year period. Rootstocks were Ramsey, 1103 Paulsen, J17–69 and 4 hybrids (designated R1, R2, R3 and R4) derived from parentage involving Vitis champini, V. berlandieri and V. vinifera. Of measured yield components (bunches per shoot, bunches per vine, weight per bunch, weight per berry and total yield), only weight per berry was significantly reduced by high salinity (3.50 dS/m) in each year of the trial with the exception of Sultana on 1103 Paulsen and R2 in 1991 and Sultana on Ramsey in 1993. Weights of one‐year‐old pruning wood were also reduced by high salinity in all years for own roots and all rootstocks, with the exception of R2. Mean yield values at each salinity level over the five‐year period of the trial were highest for Sultana on Ramsey, 1103 Paulsen and R2. High salinity had no effect on five‐year mean yields of Sultana on Ramsey, 1103 Paulsen and R2. Yield (five‐year means) of Sultana on Ramsey and R2 at 1.75 dS/m were significantly higher than at 0.40 dS/m by 14.6% and 13.4% respectively. In contrast, 5‐year mean yields of Sultana on J17–69, own roots, R1, R3 and R4 at 3.50 dS/m were reduced by 54, 30, 20, 30 and 30% respectively. Yield of Sultana on J17–69, R1 and R4 rootstocks was reduced by 47, 20 and 24% respectively at 1.75 dS/m. When yield was regressed against bunches per vine and weight per bunch for Sultana on own roots and on Ramsey rootstock, bunches per vine was the main determinant of yield, while weight per berry showed a poor correlation with yield at all salinity levels. Rootstock ranking for salt tolerance based on yield at high salinity was the same as rankings for pruning wood weights at high salinity. The same occurred at medium salinity, demonstrating that vigour imparted by the rootstock was a major factor in Sultana salt tolerance as measured by yield. Mean root weighted soil saturation paste electrical conductivities (RWEC_e) (determined from soil saturation paste salinities and root length densities) were in the range 2.0–2.6 dS/m for the low salinity treatment, increasing to approximately 5.4 dS/m with increasing salinity of irrigation water. Yield reduction for own‐rooted vines for each 1.0 dS/m increase in RWEC_e above 2.6 dS/m was 9.3%.     

Effect of salinity and Ramsey rootstock on ion concentrations and carbon dioxide assimilation in leaves of drip-irrigated, field-grown grapevines (Vitis vinifera L. cv. Sultana)

Salinity treatments of 0.43, 1.7 and 3.4 dS/m were applied through a drip-irrigation system to four-year-old vines of own-rooted Sultana (S_O) and Sultana on Ramsey rootstock (Sr) The vines were planted in spring 1987 and established for two years under irrigation with low salinity (0.43 dS/m) water before commencing the range of salinity treatments in spring 1989. The effects of salinity and rootstock on yield, size and composition of berries, canopy size, lamina CO₂ assimilation, leaf water relations and lamina ion concentrations were studied between veraison and harvest during the second season of salinity treatments. Mature leaves of S_R had higher rates of CO₂ assimilation (leaf area basis) and stomatal conductance than comparable leaves of S_O. The high salinity treatment (3.4 dS/m) reduced CO₂ assimilation rate of S_O but not of S_R. Medium salinity (1.7 dS/m) had no significant effect on CO₂ assimilation rate of either type. Laminae of S_O accumulated significantly higher concentrations of chloride than S_R vines at all salinity levels. There was a significant negative correlation (r²= 0.44) between CO₂ assimilation rate and laminae chloride of S_O. Leaf sodium concentrations increased with increasing salinity, but concentrations in laminae at high salinity were similar in S_O and S_R, with S_R showing no reduction in CO₂ assimilation. Leaf potassium concentrations were higher in S_R, but decreased with increasing salinity, whereas magnesium concentrations were similar in S_O and S_R vines but increased in both at high salinity. Leaf water potential and relative water content were not significantly affected by salinity in either S_O or S_R vines. Both vine types had reduced total leaf area and pruning wood weights as salinity increased, but they were greater in S_R at all salinity levels because of the higher inherent capacity for biomass production in S_R vines. The bigger canopies, lower lamina chloride concentrations and ‘normal’ photosynthesis rates of S_R vines at 3.4 dS/m enabled these vines to mature crops with similar berry weights, sugar contents and fruit yield compared with those of S_O vines at 0.43 dS/m. The research demonstrated the benefit of using Ramsey rootstock for Sultana under saline field conditions and provided a physiological explanation for their higher salt tolerance.