Vine Spacing Research Articles

Vine spacing of <i>Vitis vinifera</i> cv. Shiraz/101-14 Mgt. III. Grape and wine quality

Vine spacing effects of Shiraz/101-14 Mgt on a relatively high potential soil in the Breede River Valley, Robertson, South Africa, on grape composition and wine quality, were investigated. Canopies were VSP trellised and orientated approximately NNE-SSW. Spacing between rows was fixed at 2.2 m. In-row vine spacing changed from 0.3 – 4.5 m with increments of 30 cm (from 15151 – 1010 vines/ha). Grape composition and wine quality were monitored over six seasons and two grape ripeness levels. Decreasing trends of soluble solids (°B) and pH and increasing titratable acidity from narrow to wide spacing were observed. Sugar accumulation of wider spacings seemed delayed. Berry skin total anthocyanin index and phenol content showed virtually no change. Malvidin mono-glucoside and its p-coumaroyl and acetyl derivatives were present in the highest concentrations, followed by peonidin-, petunidin-, delphinidin- and cyanidin mono-glucosides and derivatives, each vine spacing treatment displaying a unique grape anthocyanin profile. The narrower spacing of vines seemed to favour skin anthocyanin accumulation compared to wider spacing. Decreasing trends in wine total anthocyanin intensity, anthocyanin density, and phenols were observed from narrow to wide spacing; all had higher levels in wines from riper grapes. Individual wine anthocyanin concentrations also showed qualitative profile changes. The first regression join points for all anthocyanins occurred around 1.8 – 2.4 m vine spacing; those for malvidin and derivatives consistently appeared at 1.8 m spacing. Although volatile compounds only seemed to respond to ripeness level and not to vine spacing, wine sensory quality generally decreased with wider vine spacing at both grape ripeness levels. Given the changes in biotic and abiotic growth conditions with wider vine spacing, the results likely displayed adaptation to the combined impact of increasing light exposure, berry temperature, physiological functioning, vegetative and reproductive growth ratios, and plant stress. The study showed the prominent role of plant spacing in sustainable grape growing and wine outcomes and thus the importance of judicious decision-making during the establishment and management of vines under any growth conditions and in any terroir.

Vine spacing of <i>Vitis vinifera</i> cv. Shiraz/101-14 Mgt II. Establishment, and vegetative and reproductive growth

Knowledge of vine growth reaction to plant spacing under relatively high potential soil conditions is limited. This study aimed to determine the effects of vine spacing (with fixed row spacing) of Shiraz (clone SH 9C)/101-14 Mgt on a relatively high potential soil in the Breede River Valley, Robertson, South Africa on establishment and training labour, aboveground growth, and yield. The vineyard was planted in 2008 to a Vertical Shoot Positioning trellis, a fixed row spacing of 2.2 m and row orientation of approximately NNE-SSW (30 °). The 15 in-row vine spacing treatments changed from 0.3 - 4.5 m with increments of 30 cm (from 15151 – 1010 vines/ha). Results were generated over six seasons after cordon development was completed. Grapes were harvested at two ripeness levels. Clear groupings were evident for establishment and further training management. Total costs showed trends with an optimal of around 1.8 m vine spacing, but were markedly higher for closer spacing. Canopies developed uniformly with cordon extension. General vegetative growth (over treatments) varied according to seasonal conditions. Individual leaf size was higher for more closely spaced vines. Total vegetative growth parameters mostly showed increasing and decreasing trends on a /vine and /ha basis, respectively, with an increase in spacing. Yields showed a general increase with wider spacing on a /vine and /ha basis. Yield:cane mass ratios displayed an increasing trend from narrow to wide vine spacing, as did fertility and bunch mass. The bunches from the narrowly spaced treatments seemed more compact. Growth and yield parameters showed very clear trends reaching an optimal at around 1.8 m vine spacing. The results of this study can be applied in vine spacing selection and sustainability strategies for different terroirs. Comprehensive guidelines for extrapolation to different growth conditions and terroirs are provided.

Vine spacing of <i>Vitis vinifera</i> cv. Shiraz/101-14 Mgt. I. root growth and physiological activity

Knowledge of vine reaction to plant spacing under relatively high potential soil conditions is limited. This study comprised effects of vine spacing (with fixed row spacing) of Shiraz (clone SH 9C)/101-14 Mgt on a high potential soil in the Breede River Valley, Robertson, South Africa, on soil conditions, root system distribution, and vine physiological reaction. The vineyard was planted in 2008 to a VSP trellis, with a fixed row spacing of 2.2 m and a row orientation of approximately NNE–SSW (30°). In-row vine spacing changed from 0.3–4.5 m with increments of 30 cm (from 15151–1010 vines/ha), totalling 15 treatments. After the completion of cordon development, results were generated over six seasons. Soil conditions seemed generally uniform and showed no obvious characteristics that could have affected treatments differentially. An increase in density occurred in fine, extension and permanent root categories with closer spacing, increasing the total number of roots/ha. Roots penetrated deeper with closer vine spacing. Vine spacing impacted physiological parameters and revealed a complex interplay between root distribution, vine structure expansion, canopy microclimate, water relations, photosynthetic output, berry temperature, carbon distribution, and day/night recovery that would affect grape composition and wine quality. Optimum vine spacing appeared to be 1.8 m, both closer and wider spacing leading to limitations in physiological activity. Interactions amongst below- and aboveground growth and physiological parameters are comprehensively discussed with a focus on sustainability.

High Planting Density Reduces Productivity and Quality of Mechanized Concord Juice Grapes

The choice of planting density is a key decision for grapegrowers to make before vineyard establishment, with long-term implications. The field trial described here, with drip-irrigated, machine-pruned Concord juice grapes, tested the effects of two between-row distances (2.44 m and 2.74 m) and four within-row distances (0.91, 1.83, 2.74, and 3.66 m), resulting in planting densities ranging from 997 to 4485 vines/ha, on yield formation and fruit composition. Canopy size, yield components, and fruit composition were measured over six years, starting in year 3 after planting. While in the first cropping season the yield with 0.91 m and 1.83 m vine spacing (11.8 t/ha) was twice that with 2.74 m and 3.66 m (5.6 t/ha), on average over the five subsequent years, the yield of 0.91-m vines was 38% lower (18.2 t/ha) than at the other planting distances (29.2 t/ha). During the last four years, the average yield of vines planted with 2.44 m between rows was 2 t/ha greater than that at 2.74 m. The yield potential and fruit quality of closely spaced vines (0.91 m) was compromised by their vigorous growth, high canopy density, and poor microclimate, which resulted in fewer clusters/vine, fewer berries/cluster, lower cluster weights, and more bunch-stem necrosis. Leaf death in the canopy interior was associated with nutrient remobilization and high potassium and pH in the juice from 0.91-m vines. Juice total soluble solids, titratable acidity, and color remained unaffected by planting density. These results show that planting juice grapes at high density in irrigated and highly mechanized vineyards is detrimental to both cropping potential and fruit quality.

The significance of scion × rootstock interactions

Aims: Rootstocks provide protection against soil-borne pests and are a powerful tool to manipulate growth, fruit composition and wine-quality attributes. The present study aimed to assess the consistency of rootstock effects on the growth and fruit composition of scion varieties and identify scion × rootstock interactions.Methods and results: Vine performance and fruit composition of hot-climate, drip-irrigated, spur-pruned Chardonnay, Cabernet Sauvignon and Shiraz, grafted on seven rootstocks, was assessed over five seasons from 2013 to 2017. Rootstocks included Ramsey, 1103 Paulsen and 140 Ruggeri and four promising selections from the CSIRO rootstock development programme. Vines were trained as quadrilateral cordons on a two-wire vertical trellis of height 1.8 m and 3.0 m row × 1.8 m vine spacing, and irrigated with 5.5–6.0 ML/ha of water each season. The study was conducted with mature vines, established in 2006, as a randomised block design with five replicates. There were significant effects of both variety and rootstock on yield, number of bunches, bunch weight, berry weight (scion only), berries per bunch, pruning weight and the Ravaz Index (yield/pruning weight). Despite identical management practices, there were large differences between scion varieties in key growth characteristics across rootstocks. Chardonnay produced a high yield (mean 25.2 kg/vine) with low pruning weight (2.3 kg/vine) and a high mean Ravaz Index value of 12.1. Shiraz had the highest yield (27.4 kg/vine) with high pruning weight (5.1 kg/vine) and a Ravaz Index of 6.3. Cabernet Sauvignon had the lowest yield (15.9 kg/vine) and highest pruning weight (6.6 kg/vine) and a very low Ravaz Index value of 3.0. Effects of rootstock on growth characteristics were smaller than the effects of variety, with mean yields ranging from 19.5 to 25.9 kg/vine, pruning weights ranging from 3.24 to 6.13 kg/vine and mean Ravaz Index values ranging from 5.54 to 8.63. Each variety was harvested when the mean total soluble solids reached 25.0 °Brix. Significant effects of variety and rootstock on fruit composition, included pH, titratable acidity (scion only), malate, tartrate (scion only), yeast assimilable nitrogen (YAN); and for the red varieties, total anthocyanins (scion only) and phenolic substances (scion only). Significant interactions between scion variety and rootstocks were found for yield, number of bunches, berry weight, pruning weight and Ravaz Index. The effect of rootstock on bunch weight and berries per bunch was consistent across scions. Significant scion × rootstock interactions were also found for pH and YAN. For each variety, significant effects of rootstock on fruit composition were linked to growth characteristics. However, these relationships, based on correlation analyses, varied for each scion.Conclusions: The study has shown that growth characteristics and fruit composition of the major varieties was not consistent across seven rootstock genotypes, as significant scion × rootstock interactions were determined. Hence, different rootstocks may be required for each variety to optimise scion performance and fruit composition. The study has also shown that the new CSIRO rootstock selections, covering a range of vigour classifications, may be useful alternatives to those currently in use by industry.Significance and impact of the study: The study has shown that the performance of scion varieties, and to a lesser degree the fruit composition, is dependent on rootstock choice. The inherent vigour of the scion variety must be considered in rootstock selection. Furthermore, individual scion/rootstock combinations may require specific irrigation, pruning or canopy management to achieve vine balance and optimise fruit and wine composition.

Vegetative and Reproductive Responses of Mature Cabernet Sauvignon Grapevines Converted from Spur Pruning to Cane Pruning at Five-Foot In-Row Vine Spacing

Summary Goals: Once established, vineyards are generally constrained by vine and row spacing and trellis configuration, which restricts how these variables can be modified. Regardless, such post-planting modifications may be desirable. This project chronicles vine performance following the conversion of seven-yr-old, cordon-trained, spur-pruned vines (“spur-pruned”) to head training and cane pruning (“cane-pruned”) with vines spaced 5 ft (1.5 m) apart in the row. While there are both pros and cons with either system, head training and cane pruning has an operational advantage in that less labor is expended on shoot-thinning because of retention of far fewer basal buds with cane-pruned vines. At issue, though, is a perception or reality that relatively wide in-row vine spacing (e.g., ≥4 or 5 ft) leads to uneven shoot development and nonuniform fruit ripening on long canes. We hypothesized that nonuniformity of shoot growth and development would lead to increased variability of fruit maturity at harvest with the conversion from spur pruning to cane pruning, with mature vines planted 5 ft (1.5 m) apart in the row. Key Findings: In comparison to spur pruning, the cane-pruned vines exhibited: (i) delayed budbreak and bloom; (ii) fewer, but more fruitful shoots; (iii) lower cane-pruning weights; and (iv) similar canopy architecture, primary fruit chemistry at harvest, and uniformity of pruned cane weights. Impact and Significance: Although we hypothesized that a 5 ft (1.5 m) in-row vine spacing might lead to nonuniform shoot development and fruit ripening on bilateral canes, this proved not to be the case. Although there was variation in components of yield for cane-pruned vines compared to spur-pruned vines, fruit maturity indexed as soluble solids concentration was similar between the two systems in the four seasons after conversion. While spur pruning has some advantage from the standpoint of reduced or eliminated time to tie canes following dormant pruning, the disadvantage, at least with Cabernet Sauvignon, as used here, is the propensity of cordon training to produce abundant basal shoots, which add excess crop and canopy density or additional labor to remove those shoots. A closer in-row spacing might be advised for cane pruning in new vineyards; however, it is possible to effectively convert spur-pruned vines back to cane pruning even for mature vines spaced 5 ft (1.5 m) apart in the row should that conversion be desired for labor savings, anticipated fruit quality improvements, or other reasons.

Effects of grape quality on the environmental profile of an Italian vineyard for Lambrusco red wine production

The food industry contributes disproportionately to many global-scale environmental problems. The winemaking process involves many different phases varying from the grape production, bottling and distribution. Many of these processes contribute to negative impacts on the environment and life cycle assessment can assist in identifying the possible strategies and opportunities to improve the environmental performance of products during their entire life cycle.The purpose of this work is to assess the environmental impacts of the cultivation, management and disposal of an Italian vineyard during its entire life cycle. In particular, the aim of this work is to assess, on the basis of different properties of the soil, the most suitable vine spacing in order to reduce the environmental impacts. To assess the environmental impact, the analysis was conducted using the SimaPro 8.0.4 software and IMPACT 2002+ evaluation method. Data related to cultivation, management and disposal were directly collected from the producer or from Ecoinvent database while data related to the environmental emissions arising from the use of fertilizers and heavy metals, calculated following the criterion proposed by Ecoinvent, were reported to the functional unit. In this study, the grape sugar content, that is related to the wine quality, was considered as a coproduct. The results show that, taking into account the grapes quality, the damage is lower for the 3 × 0.8 planting pattern even if the vineyard lifetime is longer. LCA results show that the most critical issues are related to direct emissions of fertilizers and pesticides and to land occupation.

Quality parameters of wine grape varieties under the influence of different vine spacing and training systems

Physicochemical and biochemical indices, which characterize quality of white wine grape varieties Zagrey and Aromatnyi of selection of NNC «IV&W named after V. Ye. Tairov», (harvest of 2016) were determined. The field trial which includes various variants of planting density and vine training systems, made it possible to study the influence of viticulture practices on the criteria of carbohydrate-acid and phenolic complex, oxidative enzyme system of grapes. Low-density plantings of Aromatnyi variety (2222 vines per ha) were characterized by harvest that slightly exceeded the grapes obtained from dense plantations (4000 vines per ha) in terms of carbohydrate-acid and phenolic complexes. The most optimal in terms of the mass concentration of sugars, phenolic substances, polymer forms, macerating ability of must, activity of oxidizing enzyme system was cultivation of this variety on a 160 cm – high trunk. Growing grapes of Zagrey variety with vine spacing, corresponding to 4000 plants per ha, contributed to obtaining harvest with optimal parameters of carbohydrate-acid complex, low technological reserve and mass concentration of phenolic compounds, moderate macerating ability and activity of monophenol monooxygenase in must. Training vines of this variety on a 40 cm high trunk with vertical shoot positioning led to significant deterioration of grape quality due to increased content of phenolic substances and their polymer forms, high macerating capacity of must.

The Effect of Vine Spacing on Some Physiological Aspects of Vitis vinifera L. (cv. Pinot noir)

The effect of vine spacing on leaf temperature, radiant energy, some canopy characteristics, leaf-water potential, stomata! conductance, the rate of transpiration and the rate of photosynthesis was measured and discussed. With more closely spaced vines, canopies were less dense than with more widely spaced vines mainly because of less vigorous shoot growth. The consequent better sunlight penetration favoured the physiology of more closely spaced vines early in the season. During the latter part of the season the situation was reversed and the physiology of more widely spaced vines was favoured mainly because of better water supply.

Flavour Development in the Vineyard: Impact of Viticultural Practices on Grape Monoterpenes and their Relationship to Wine Sensory Response

Monoterpenes are responsible for the distinctive flavour of grape cultivars such as Gewiirztraminer, Riesling and several muscat cultivars. These components are present as odour-active free volatile terpenes (FVT) and as potentially volatile terpenes (PVT), i.e. glycosides and polyols capable of releasing FVT by temperature-, pH-, or enzyme induced hydrolysis. Our first work focused on the impact of fruit exposure on terpene concentrations in Gewiirztraminer. Fully-exposed fruit consistently displayed higher FVT and PVT than partially-exposed and fully-shaded fruit. This knowledge was utilised to investigate effects of cultural practices. Hedging and basal leaf removal (BLR) increased FVT and PVT levels, while multi-site experiments also indicated that hedging and BLR could increase FVT and PVT in berries and musts of early-season cultivars such as Bacchus, Pearl of Csaba, Gewiirztraminer, Schonburger and Siegerrebe. Canopy division, BLR and increased vine spacing also increased FVT and PVT concentrations in Riesling fruit. Low-heat unit sites appear to promote accumulation of monoterpenes in Vitis vinifera more than warmer sites, when compared at equal growing degree days. Prefermentation practices such as delayed harvest, prolonged pressing and skin contact were also shown to increase must terpene content. In many cases, these differences in terpene concentrations in the berries and musts were organoleptically detectable in wines. Our conclusions to date are: (1) PVT are more responsive to viticultural and enological practices than FVT; (2) FVT and PVT are rarely correlated with soluble solids, titratable acidity or pH, and thus cannot be predicted by standard harvest indices; (3) Losses in FVT and PVT can occur between the berry and juice stages, hence the desirability of skin contact; (4) FVT and PVT concentrations can, in some cases, be related to wine-tasting results.

Diez portainjertos de vid: Efectos sobre el crecimiento, la producción y la composición de la uva del cv. Sauvignon blanc en la denominación de origen rueda (España)

The knowledge of the behaviour of different grapevine rootstocks is basic to achieve a good adaptation of vine to its growing area. With the objective of knowing the agronomic and qualitative response of cv. Sauvignon Blanc to the use of several rootstocks, a trial was established in 2006 in the D.O. Rueda. The vines are vertical trellised, with bilateral Royat cordon pruning, and the vine spacing is 2.60 m × 1.25 m. The row orientation is NNW (N-25°). The experimental design consisted of randomized blocks with 4 replications and elemental plot of 60 vines. Over the period 2010–2014 it has been developed the study of the following 10 rootstocks (treatments): 110R, 101-14M, 420A, 3309C, 41B, 161-49C, 196-17C, Fercal, Gravesac and RGM. The rootstocks 420A and 41B showed a production higher than 50% with respect to 196-17C and 161-49C, and higher to 100% than RGM, due to the number of clusters per vine and, in greater amount, to the cluster weight. Fercal and Gravesac showed an increase of pruning wood weight of 24% with respect to 196-17C and 161-49C, and 90% with respect to RGM, mainly due to the shoot weight. The sugar concentration increased with 101-14M, 196-17C and Fercal, and became reduced with 161-49C, 41B and RGM. The pH of must was reduced with Fercal whereas the titratable acidity increased, which also showed increase with Gravesac and 161-49C. The tartaric acid hardly increased slightly with Fercal and 161-49C, whereas the malic acid increased with Gravesac and Fercal, and was reduced with 41B, 3309C, RGM and 101-14M. The potassium concentration increased with 196-17C, Gravesac and Fercal, and was reduced with 41B, 161-49C, 420A and 3309C. The effects observed show alternatives for rootstock election according to the growing conditions and objectives of the vineyard.

Cane pruning on Chardonnay grapevine in the high-altitude regions of Southern Brazil

High-altitude regions of southern Brazil, located above 900 m above sea level, the cordon training with spur pruning is widely used because of easier application. In these regions, Chardonnay wine grape shows potential to produce quality wines, however, in commercial vineyards, the training system used has not provided productivities that makes economically viable the cultivation of this variety. Given this, the present study aimed to evaluate the effect of different cane-pruning systems on the vegetative, productive and enological potential of Chardonnay grapevines grown in the high-altitude region of Southern Brazil. The experiment was conducted in a commercial Chardonnay vineyard, located in Sao Joaquim – Santa Catarina State (28o 17 ′39”S and 49∘ 55′56” W, to 1230 m a.s.l) during 2015 and 2016 vintages. Chardonnay vines (grafted on 1103 Paulsen) were planted in 2010, with a 3.0 m (row) × 1.0 m (vine) spacing. The treatments consisted of different cane-pruning systems: Cordon spur-pruning (control); Sylvoz; Cazenave; Capovolto; single Guyot and double Guyot. Pruning was performed in August of each year when the buds were in the green tip developmental stage. Data was analyzed by Scott Knott test (p g−1 grape at 2016 vintage. Commercial maturity of grapes (soluble solids, acidity and polyphenols) did not differ among training systems studied. The results suggest that cane-pruning systems could be an alternative to increase production efficiency of Chardonnay in high-altitude region of southern Brazil.

Vine spacing on cv. Tempranillo in the Appellation of Origin Cigales (Spain): Agronomy and quality effects

This paper studies the vegetative, productive and qualitative behavior of the Tempranillo variety, vertically trellised trained, according to a placement of vines with three different distances (1.04, 1.40 and 1.80 meters) in the row and a common distance between rows (2.40 meters), in order to determine the most suitable vine distance for the growing conditions. The experimental test has been developed for the period 2007–2011 in the Appellation of Origin Cigales, in Valladolid (Spain). The reduction of vine distance has favored the vegetative growth, through the shoot weight, while the grape yield has been slightly higher in the intermediate vine distance, 1.40 m, through the cluster weight. Ravaz index showed some increase with the increasing of vine distance, derived from the decrease of pruning wood. In qualitative terms, the variation of the vine distance did not significantly modify the basic composition of the grape. Therefore, the choice of the vine distance involves the convenience to assess both potential effects in terms of production and economic objectives of the new plantations, in accordance with the characteristics of each growing situation.

Training System and Vine Spacing Impact Vine Growth, Yield, and Fruit Composition in a Vigorous Young ‘Noiret’ Vineyard

An experimental vineyard was planted in Geneva, NY, in 2007 to determine the impact of training system [low bilateral cordon with vertical shoot positioning (LVSP), high wire bilateral cordon (HWC)], vine spacing (1.8 and 2.4 m), and root system [own-rooted, grafted onto ‘101–14 Mgt’ (Vitis riparia × Vitis rupestris)] on vine growth, yield, fruit composition, and wine quality of the recently-released winegrape ‘Noiret’ (Vitis hybrid). Yield components were generally unaffected by training system in 2009, but vines spaced at 2.4 m had about six fewer clusters per meter of canopy, lower pruning weights by 0.24 kg·m−1, and clusters that were 0.01 kg greater in mass compared with vines spaced at 1.8 m. In 2010, HWC yielded 0.98 kg·m−1 more than LVSP, and had a higher crop load ratio by 0.8. Larger vine spacing increased yield by 0.32 kg·m−1 and increased crop load ratio by 0.3. Grafted vines increased yield by 0.36 kg·m−1 and crop load ratio by 0.3. Training system and vine spacing had minimal impact on fruit composition in both years. Rank sum analysis indicated a consumer preference for the aroma of wines from the HWC/2.4-m treatment compared with wines from the LVSP/1.8-m treatment in 2009, and a consumer preference for the aroma of wines from the HWC/1.8-m treatment compared with wines from the LVSP/1.8-m treatment in 2010. Results suggest that the LVSP system is not a suitable choice for vigorous ‘Noiret’ vines because of low yields, low crop load ratios, and low preference rankings of LVSP wines by the consumer sensory panel.

Long-term Performance of Barbera Grown under Different Training Systems and Within-Row Vine Spacings

The effects of training systems established as vertically shoot-positioned spur-pruned low cordon (SPC), single high-wire cordon (HW), single Guyot (SG), and vertically split double Guyot (DG) were tested over five years (2003–2007) on <i>Vitis vinifera</i> L. cv. Barbera vines planted at 2.5 m interrow and at 0.9 m, 1.2 m, and 1.5 m within-row spacings. In the spur-pruned (SPC and HW) systems, total shoots per count node were about three-fold the values recorded in SG and DG, while vine capacity as total leaf area throughout the trial was highest in SPC (6.48 m²) and lowest in SG (2.93 m²), although the latter bore the most vigorous shoots. Vine capacity measured as leaf area decreased linearly with increasing within-row spacing. Yield per meter of row decreased by ~20% at 1.5 m as compared to 0.9 m vine spacing. No significant differences were found in the yield per vine across training systems, as higher shoot number in SPC and HW was offset by higher shoot fertility and cluster weight in the cane-pruned systems. Must composition at harvest was similar among SPC, HW, and SG, while DG produced grapes of overall inferior quality. Vine spacing had no effects on grape composition. Results indicate that in Barbera similar crop potential and quality expression can be achieved in either cane- or spur-pruned training systems when properly managed. Vine spacing at 0.9 m within-row is advisable as it ensures 20% higher yield per hectare at very similar grape quality across training systems.

Evaluation of yield, fruit quality and photosynthesis of two trainining-trellis systems and canopy management practices for Carlos and noble muscadine grapes in Florida

&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Aims&lt;/strong&gt;: The study was designed to evaluate and recommend most suitable training/trellis systems, canopy management practices and vine spacing for commercial muscadine grape varieties in Florida.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Methods and results&lt;/strong&gt;: During 3rd growing season of 'Carlos' and 'Noble' muscadine grape cultivars biometrical data for “photosynthetic rate”, “vine balance”, “yield components”, “fruit composition” and “fruit ripening pattern ” were evaluated as a result of the vine spacing, and training/trellis system treatments. The mean values for the varieties indicated variation between “yield components”, “fruit ripening pattern” and “fruit composition” of single wire, double cordon (SWDC) and Munson T-cross arm, double cordon (MTDC) training/trellis systems. The training/trellis system and the leaf position had a statistically significant effect on photosynthetic active radiation (PAR) and photosynthetic rate for 'Noble' variety. Leaves adjacent to the cluster on a single wire presented higher PAR and photosynthesis rate at 1% level of significance. Leaves immediately downward to the cluster had also a superior photosynthesis rate (p ² 0.01) in the T- trellis/training system compared with the same class of leaves in our SW system.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Conclusion&lt;/strong&gt;: Carlos and Noble muscadine varieties demonstrated significant variation between the photosynthetic rate, yield components, fruit ripening pattern and fruit composition of single wire, double cordon (SWDC) and Munson T-cross arm, double cordon (MTDC) training/trellis systems, with better performance of the divided canopy.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Significance and impact of study&lt;/strong&gt;: The ongoing research will provide essential information to some of the fundamental questions on the use of training/trellis system and canopy management practices for hot climate grapes and will improve the viability and competitiveness of commercial grape growing in Florida and southeastern states.&lt;/p&gt;

Management practices for Sunmuscat (Vitis vinifera L.): a new drying variety

Sunmuscat grapevines, managed on one of three trellis × two row spacing configurations, and grown on either their own roots or grafted onto Ramsey rootstock, were assessed over nine seasons (1990–1998 inclusive). The three trellis systems comprised (1) a 0.3 m narrow T-trellis (NT), (2) a 1.2 m wide T-trellis (WT), both with a 3.3m row spacing and a height of 1.2 m, and (3) a high (1.8 m) hanging cane (HC) system based on bi-lateral cordons with a 2.2 m row spacing. Vine spacing within rows was 2.4 m irrespective of row width. A trellis drying treatment was compared with hand harvest during 1991–1995. Over the nine seasons, individual WT vines sustained highest yields of fresh grapes (23.7 kg/vine.season) compared to either NT (20.9 kg/vine) or HC vines (20.8 kg/vine) respectively (P < 0.001). However, HC vines expressed a considerable production advantage on a per hectare basis, viz. 41.3 t/ha, due to closer row spacing. Corresponding vineyard productivity for NT and WT vines was 26.4 and 29.9 t/ha respectively. Both WT and HC vines showed significantly higher bunch and shoot numbers than the NT treatment (P < 0.05 and P < 0.001, respectively). Nevertheless, trellis treatment had no effect on fruitfulness, berry weight, bunch weight, total soluble solids or titratable acidity. Taken overall, vines grafted to Ramsey rootstock had higher mean yields than vines on their own roots (i.e. 23.6 and 20.1 kg /vine, respectively P < 0.001) due to more berries per bunch and larger berries, despite having significantly fewer shoots and bunches. There was no long term evidence for incompatibility of Sunmuscat grafted to Ramsey rootstock. Compared to hand harvest of fresh grapes, trellis drying had no effect on yield, shoot and bunch numbers. Development of significantly smaller berries with trellis drying was offset by higher levels of total soluble solids. Sunmuscat is clearly a highly productive variety and is suited to canopy management on tall, cordon-based hanging cane systems which are also amenable to trellis drying.

Impact of Training System and Vine Spacing on Vine Performance, Berry Composition, and Wine Sensory Attributes of Riesling

Own-rooted Riesling vines were subjected over a four-year-period to five training treatments (alternate double crossarm, ADC; Lenz Moser, LM; low cordon, LC; low-V, LV; and pendelbogen, PB) and three vine spacings (1.4, 1.8, and 2.4 m). Divided canopies led to weights of cane prunings (vine size) and mean cane weights that were optimal (0.32 to 0.65 kg/m canopy; 15.4 to 34.5 g/cane). Yields were consistently highest for divided canopies as well. Crop loads (ratio of yield: weight of cane prunings) of divided canopies exceeded the presently accepted level (10 to 12) beyond which wine quality could be compromised, but berry, must, and wine composition (Brix, titratable acidity, and pH) were not strongly impacted by training system. Increasing vine spacing led to lower vine size (per m row), cane weights, and occasionally reduced Brix. Riesling wines were also not strongly influenced by training system, except for higher vegetative aroma in the ADC wines. These data strongly suggest that high wine quality may be obtained from divided canopies despite large crop size and high crop loads.

Impact of Training System and Vine Spacing on Vine Performance, Berry Composition, and Wine Sensory Attributes of Seyval and Chancellor

Own-rooted Seyval and Chancellor vines were subjected over a four-year period to five training treatments (Geneva Double Curtain, GDC; Hudson River Umbrella, HRU; 6-arm Kniffin, 6AK; midwire cordon, MWC; and Y-trellis, YT) and three vine spacings (1.4, 1.8, and 2.4 m). Divided canopies led to weights of cane prunings (vine size) and mean cane weights that were optimal (0.32 to 0.65 kg/m canopy; 15.4 to 34.5 g/cane) for Chancellor but below optimum (0.19 to 0.27 kg/m canopy; 9.4 to 13.9 g/cane) for Seyval. Yields were consistently highest for divided canopies as well as 6-AK. Crop loads (ratio of yield:weight of cane prunings) of divided canopies exceeded the presently accepted level (10 to 12) beyond which wine quality could be compromised, but berry, must, and wine composition (Brix, titratable acidity, and pH) were not strongly impacted by training system. Increased vine spacing led to smaller vine size (per m row), lower cane weights and yield (Seyval only), and occasionally reduced Brix. GDC wines produced from Seyval were characterized by highest melon flavor, lowest earthy and vegetative flavors, and lowest astringency. Chancellor GDC wines had highest berry flavor. These data strongly suggest that high wine quality may be obtained from divided canopies despite large crop size and high crop loads.

Ecophysiology and vine performance of cv. “Aglianico” under various training systems

A 2-year study was conducted to evaluate ecophysiological characteristics and yield–quality performance of cv. “Aglianico” ( Vitis vinifera L.) grapevines trained to three different trellises at the same intrarow vine spacing and bud load per meter of row length. Bilateral guyot (BG) showed the lowest vine capacity and bilateral spur-pruned cordon (BSPC), with a vertical shoot positioning had the highest total leaf area (LA) and pruning weight. Despite very comparable crop levels among trellises, quality decreased considerably in the bilateral free cordon (BFC) vines with respect to the systems with upright shoot growth. BFC vines showed significantly lower sugar concentration (°Brix), anthocyanins and phenols, and higher pH and K + according to a pattern frequently associated with excessive within-canopy shading. Shading was aggravated in the BFC vines by canopy rotation, which probably resulted in an increase of LA density per volume unit. Moreover, the BFC canopies had more close-to-horizontal oriented leaves and from veraison onward, placed the most functional median and apical leaves in the lower or less illuminated portion of the canopy. These factors may have combined to diminish total vine photosynthesis in BFC-trained vines. The data also pointed out that the differences among trellises could not have been predicted simply on the basis of widely accepted indicators of crop load (e.g. the yield-to-pruning weight ratio) or canopy density (e.g. leaf area-to-canopy surface area (LA/SA)).