GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 Sustainable viticulture’ the “semi‐minimal” pruned “hedge” system for grape vines long term experience on cv. Sangiovese (Vitis vinifera L.)

Sustainable viticulture’ the “semi‐minimal” pruned “hedge” system for grape vines long term experience on cv. Sangiovese (Vitis vinifera L.)

Abstract

Context and purpose of the study ‐ In previous experiments carried out in Bologna on Sangiovese grapevines raised with the Australian “Minimal Pruning” system, it has been shown that this system left an excessive burden of buds on the vine (650/meter of row) and inhibited the plant from correctly activating its physiologic self‐regulating mechanisms, thus causing alternancy and drops in the sugar content. However, “Minimal Pruning” also reduced labor time and resulted in loose grape bunches on the vine, which are less prone to fungal diseases. Considering the importance of these last results, the University of Bologna has experimented with a cultivation method based on the Australian technique, but modified so as to reduce the bud load and regulate production without losing the advantages of low cost and healthier grapes. The new system, trained to a “Hedge” form with “Semi‐Minimal” mechanical pruning, has been tested on Sangiovese grapevines since 1990 and has undergone important structural modifications, which might also make it suitable for other grape varieties.

Material and methods ‐ The initial research on the Sangiovese grapevine trained as a Hedge compared it to the classic Spur‐Pruned Cordon (SPC). The Hedge productive surface was 1.2 meters tall and was managed with mechanical “Semi‐Minimal” pruning (400 buds/m of row, i.e. 40% less than Australian “Minimal Pruning”), while the classic SPC was managed with traditional manual pruning (18‐buds/meter of row). Between 2000 and 2008, the main growth, production and quality characteristics of SPC and Hedge were identified and an assessment was made of the likelihood of shoot density in the lower areas of the Hedge (as already mentioned, 1.2 m tall) to verify the acrotony effect.Moreover from 2013 to 2018 a second model of Hedge, 0.8 m tall (“Shorter Hedge”) was used on Sangiovese grapevines (235 buds/meter of row, i.e. 65% less than Australian “Minimal Pruning”). For the “Shorter Hedge” the principal 2013‐2018 behavioral parameters were identified and the spatial distribution of shoots and bunches along the productive Hedge wall was also verified.

Results ‐ The results of the first investigation (2000‐2008) showed that in respect to the SPC (18‐buds/m), the 1.2 m tall Hedge (400 buds/m) gave rise to a larger crop of similar quality to that of the SPC, with a greater number of bunches that were smaller, looser and completely free from botrytis. Nevertheless, in the lower part of the 1.2 m tall Hedge, a small drop in the number of shoots produced was observed after few years.In the second investigation, carried out between 2013 and 2018 on the Sangiovese “Shorter Hedge”, with a 0.8 m tall productive surface (235 buds/m), the data confirmed that the lesser height of the yield wall and the relate lower bud number improved the self‐regulation and equilibrium of the vines, markedly reducing the annual variability of the different grape parameters. Overall, the vines always produced quantitatively and qualitatively to satisfaction, with many small bunches free from rot. During the trial, a decreasing of shoot and cluster density was not observed in the lower parts of the 0.8 m tall Hedge.Today, after almost 20 years of research, the Hedge system has shown itself to be capable of being practically applied to other grape varieties thanks to its reduced management costs, complete adaptability to integrated mechanization and the positive results regarding the yield and grape quality.

DOI:

Publication date: June 22, 2020

Issue: GiESCO 2019

Type: Article

Authors

Cesare INTRIERI, Ilaria FILIPPETTI, Gianluca ALLEGRO, Gabriele VALENTINI, Chiara PASTORE, Emilia COLUCCI

Dipartimento di Scienze e Tecnologie Agroalimentari- Università di Bologna

Contact the author

Keywords

Grapevine, Training System, Self-regulation, Mechanization, Semi-Minimal pruning

Tags

GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Analysis of Cabernet Sauvignon and Aglianico winegrape (V. vinifera L.) responses to different pedo-climatic environments in southern Italy

Water deficit is one of the most important effects of climate change able to affect agricultural sectors. In general, it determines a reduction in biomass production, and for some plants, as in the case of grapevine, it can endorse fruit quality. The monitoring and management of plant water stress in the vineyard

Modulation of berry composition by different vineyard management practices

High concentration of sugars in grapes and alcohol in wines is one of the consequences of climate change on viticulture production in several wine-growing regions. In order to investigate the possibilities of adaptation of vineyard management practices aimed to reduce the accumulation of sugar during the maturation phase without reducing the accumulation of anthocyanins in grapes, a study with severe shoot trimming, shoot thinning, cluster thinning and date of harvest was conducted on Merlot variety in Istria region (Croatia), under the Mediterranean climate. Four factors which may affect grape maturation and its composition at harvest were investigated in a two-years experiment; severe shoot trimming applied at veraison when >80% of berries changed colour (in comparison to untreated control), shoot thinning (0 and 30%), cluster thinning (0 and 30%), and the date of harvest (early and standard harvest dates). Shoot thinning had no significant impact on berry composition, despite the obtained reduction in yield per vine. Lower Brix in grapes were obtained with earlier harvest date and if no cluster thinning was applied, although at the same time a reduction in the concentration of anthocyanins in berries was observed in these treatments. On the other hand, if severe shoot trimming was applied when >80% of berries changed colour, a reduction of Brix was obtained without a negative impact on berry anthocyanins concentration. We conclude that in cases when undesirably high sugar concentrations at harvest are expected, severe shoot trimming at 80% veraison may effectively be used in order to obtain moderate sugar concentration in berries together with the adequate phenolic composition.

Terroir traceability in grapes, musts and wine: results of research on Gewürztraminer and Sauvignon Blanc grape varieties in northern Italy

In the study of terroir, a separate analysis of its many component factors can be of great help in accurately identifying a vineyard’s natural elements that impact wine quality and typicity. This research used a dedicated pluri-disciplinary approach to investigate the ecological characteristics, including geology and geographical features, of 14 vineyards that produce Gewürztraminer and Sauvignon Blanc cultivars in the alpine Alto Adige DOC wine region. Both the geopedological method using Vineyards Geological Identity (VGI) and the new Solar Radiaton Identity (SRI) topoclimatic classification method were used to provide analytical measurements and qualitative/quantitative characterisations. In addition, wide-ranging targeted and untargeted oenological and chemical analyses were carried out on grapes, musts and wines to correlate the soils’ geomineral and physical conditions with the biochemical properties of their fruits and wines. The research identified strong correlations between vineyard geo-identity and wine biofingerprint, confirming a mineral traceability of strontium rubidium ratio and some minerals distinctive to the local geology, such as K, Ca, Ag, Ba and Mn.  The study also discovered that particular geomineral and physical soil conditions of the studied vineyards are related to the different amount of amino acids, primary varietal aromas and polyphenols found in grapes, musts and wines. The research confirmed that winemaking technologies support oenological quality, although in some cases, human practices can overpower certain characteristic elements in wine, erasing the typical imprint left by the vineyards’ natural terroir, which becomes less traceable. Terroir abiotic ecological factors and vineyard identity can be classified in detail using the new VGI and SRI analysis methods to discover interrelationships between geo-pedological and topoclimatic conditions that impact wine quality. These methods are also helpful in identifying which ecological elements are exclusive to a particular vineyard or wine sub-region.

A predictive model of spatial Eca variability in the vineyard to support the monitoring of plant status

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Drought effect on aromatic and phenolic potential of seven recovered grapevine varieties in Castilla-La Mancha region (Spain)

The effects of climate change are seriously affecting the quality of wine grapes. High temperatures and drought cause imbalances in the chemical composition of grapes. The result is overripe grapes with low acidity and high sugar content, which produce wines with excessive alcohol content, lacking in freshness and not very aromatic. As a consequence, the search of varieties with capacity of produce quality grapes in adverse climate conditions is a good alternative to preserve the sustainability of vineyards. In this work, quality parameters of seven Vitis vinifera L. cultivars (five whites and two reds) recently recovered from extinction and grown under two different hydric regimes (rainfed and irrigated) were analyzed during the 2020 vintage. At harvest time, weight of 100 berries, must physicochemical parameters (brix degree, total acidity, malic acid, pH), and carbon and oxygen isotope ratios (δ13C, δ18O) were determined. Subsequently, varietal aroma potential index (IPAv) and total polyphenol index (TPI) were analyzed. Quality parameters, IPAv and TPI, showed significant differences between varieties and water regimes. Both red varieties, Moribel and Tinto Fragoso, stood out for their high aromatic and phenolic potential, which was higher under rainfed regime. Regarding to white varieties, Montonera del Casar and Jarrosuelto stood out in terms of varietal aroma potential. Montonera del Casar high acidity in its musts and Jarrosuelto showed the highest berry weights.