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…

Effect of multi-level and multi-scale spectral data source on vineyard state assessment

Currently, the main goal of agriculture is to promote the resilience of agricultural systems in a sustainable way through the improvement of use efficiency of farm resources, increasing crop yield and quality under climate change conditions. This last is expected to drastically modify plant growth, with possible negative effects, especially in arid and semi-arid regions of Europe on the viticultural sector. In this context, the monitoring of spatial behavior of grapevine during the growing season represents an opportunity to improve the plant management, winegrowers’ incomes, and to preserve the environmental health, but it has additional costs for the farmer. Nowadays, UAS equipped with a VIS-NIR multispectral camera (blue, green, red, red-edge, and NIR) represents a good and relatively cheap solution to assess plant status spatial information (by means of a limited set of spectral vegetation indices), representing important support in precision agriculture management during the growing season. While differences between UAS-based multispectral imagery and point-based spectroscopy are well discussed in the literature, their impact on plant status estimation by vegetation indices is not completely investigated in depth. The aim of this study was to assess the performance level of UAS-based multispectral (5 bands across 450-800nm spectral region with a spatial resolution of 5cm) imagery, reconstructed high-resolution satellite (Sentinel-2A) multispectral imagery (13 bands across 400-2500 nm with spatial resolution of <2 m) through Convolutional Neural Network (CNN) approach, and point-based field spectroscopy (collecting 600 wavelengths across 400-1000 nm spectral region with a surface footprint of 1-2 cm) in a plant status estimation application, and then, using Bayesian regularization artificial neural network for leaf chlorophyll content (LCC) and plant water status (LWP) prediction. The test site is a Greco vineyard of southern Italy, where detailed and precise records on soil and atmosphere systems, in-vivo plant monitoring of eco-physiological parameters have been conducted.

Climate, Viticulture, and Wine … my how things have changed!

The planet is warmer than at any time in our recorded past and increasing greenhouse emissions and persistence in the climate system means that continued warming is highly likely. Climate change has already altered the basic framework of growing grapes for wine production worldwide and will likely continue to do so for years to come. The wine sector can continue to play an important role in leading the agricultural sector in addressing climate change. From developing on…

Sustainable fertilisation of the vineyard in Galicia (Spain)

Excessive fertilization of the vineyard leads to low quality grapes, increased costs and a negative impact on the environment. In order to establish an integrated management system aimed at a sustainable fertilization of the vineyards, nutritional reference levels were established. For this purpose, 30 representative vineyards of the Albariño variety were studied, in which soil and petiole analyses were carried out for two years and grape yield and quality at harvest were measured. In both years of study, soil pH, calcium, sodium and cation exchange capacity were positively correlated with calcium content and negatively correlated with manganese in grapes. Irrigated vineyards had higher levels of aluminium in soil and lower levels of calcium in petiole. Climatic conditions were very different in the years of the study. The year 2019 was colder than usual, in 2020 there was a marked water stress with high summer temperatures. This resulted in medium-high acidity in grapes in 2019 and low acidity in 2020, with sugar levels being similar both years. A very marked decrease in must amino nitrogen was observed in 2020, with ammonia nitrogen remaining stable. The correlation of acidity and sugar values in grapes with soil and petiole analysis data made it possible to establish reference levels for the nutritional diagnosis of the Albariño variety in this region. Based on these results, an easy-to-use TIC application is currently being created for grapegrowers, aimed at improving the sustainability of the vineyard through reasoned fertilization. This study has now been extended to other Galician vine varieties.

Is wine terroir a valid concept under a changing climate?

The OIV[i] defines terroir as a concept referring to an area in which collective knowledge of the interactions between the physical and biological environment (soil, topography, climate, landscape characteristics and biodiversity features) and vitivinicultural practices develops, providing distinctive wine characteristics. Those are perceptible in the taste of wine, which drives consumer preference and, therefore, wine’s value in the marketplace. Geographical indications (GI) are recognized regulatory constructs formalizing and protecting the nexus between wine taste and the terroir generating it. Despite considering updates, GIs do not consider the nexus as a dynamic one and do not anticipate change, namely of climate. Being climate a fundamental feature of terroir, it strongly impacts wine characteristics, such as taste. According to IPCC[ii], many widespread, rapid and unprecedented changes of climate occurred, some being irreversible over hundreds to thousands of years. Climatic shifts and atmospheric-driven extreme events have been widely reported worldwide. Recent climatic trends are projected to strengthen in upcoming decades, whereas extremes are expected to increase in frequency and intensity, forcing wines away from GI definitions. Geographical shifts of viticultural suitability are projected, often moving into regions and countries different from current ones. Some authors propose adaptation in viticulture, winemaking and product innovation. We show evidence of climate changing wine characteristics in the Douro valley, home of 270-year-old Port GI. We discuss herein resist or adapt stances for when climate changes the nexus between terroir and wine characteristics. Using the MED-GOLD[iii] dashboard, a tool allowing for easy visual navigation of past and future climates, we demonstrate how policymakers can identify future moments, throughout the 21st century under different emission scenarios, when GI specifications will likely need updates (e.g., boundaries, varieties) to reduce climate-change impacts.

Inhibition of Oenococcus oeni during alcoholic fermentation by a selected Lactiplantibacillus plantarum strain

The use of selected cultures of the species Lactiplantibacillus plantarum in Oenology has grown in prominence in recent years. While initial applications of this species centred very much around malolactic fermentation (MLF), there is strong evidence to show that certain strains can be harnessed for their bio-protective effects. Unwanted spontaneous MLF during alcoholic fermentation (AF), driven by rogue Oenococcus oeni, is a winemaking deviation that is very difficult to manage when it occurs. This work set out to determine the efficacy of one particular strain of Lactiplantibacillus plantarum(Viniflora® NoVA™ Protect), against this problem in Cabernet Sauvignon must. The work was carried out at commercial scale and in a winery environment and compared the bio-protective culture with the more traditional approach of reducing must pH by the addition of tartaric acid. The combination of both was also investigated. The concentration of both Oenococcus oeni and Lactiplantibacillus plantarum was determined using qPCR. The adventitious Oenococcus oeni showed the most growth during AF in the control wine, whereas in the wines treated with Lactiplantibacillus plantarum a bacteriostatic effect against this species was observed. This effect was comparable to the wines treated with tartaric acid. This has particular commercial relevance for controlling the flora in musts with high pH, or when the addition of tartaric acid is either not permitted or is prohibitive for other reasons.