 IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Grapevine diversity and viticultural practices for sustainable grape growing 9 Effect of soil particle size on vine water status, leaf abscisic acid content and berry quality in nebbiolo grapes

Effect of soil particle size on vine water status, leaf abscisic acid content and berry quality in nebbiolo grapes

Abstract

AIM: We investigated the effect of soil texture on grapevine response to water stress, leaf abscisic acid concentration and berry quality, in two adjacent vineyards located in the renewed Cannubi hill of Barolo (Langhe area, CN, North-West Italy).

METHODS: The distance as the crow flies between the two Nebbiolo vineyards was about 250 m; cultural practices, rain, rootstocks (V. berlandieri x V. riparia), vine age were similar. The main difference between the two vineyards was the soil texture, one vineyard displaying a silty-loam soil where small dimension particles (69.4 %, clay + loam) were prevalent, with clay accounting for 18.3 % (high clay, HC), the other displaying a loam-soil, where small dimension particles were 48.2 % with clay at 14.4 % (low clay, LC). Photosynthesis, transpiration, stomatal conductance (gs) were assessed at three time points during the season by ADC Lc pro+ Photosynthesis System (Huddestone, UK) on 10 fully expanded mature leaf per plot. A Scholander pressure bomb was used for the Ψstem determination on 8 leaves. The free-ABA concentration was quantified in 3 mature and healthy leaves per plot (HPLC-DAD). On berries, we measured total soluble solids, anthocyanin concentration and profiles (HPLC-DAD), total flavonoids (Di Stefano and Cravero, 1991; Corona et al., 2015) and total proanthocyanidins, spectrophotometrically (Harbertson et al., 2015). The berry volatiles were assessed by SBSE-GC/MS (Ferrandino et al., 2012).

RESULTS: The two vineyard soils showed different rates of drying speed, higher in LC respect to HC. Nebbiolo vines grown in HC soil tended to reduce the Nebbiolo cultivar anhisohydric behaviour, closing stomata at lower values of stomatal conductance, in line with the higher leaf ABA concentration respect to LC, after moderate water stress conditions (Ferrandino and Lovisolo, 2014; Tramontini et al., 2014). At the berry level, this resulted in a significantly higher anthocyanin concentration since 15 days after véraison and in a higher percentage incidence of acylated anthocyanins. No major differences were found in total flavonoid and in total proanthocyanidin concentrations. However, as to these two last classes of compounds, further studies would be necessary as the spectrophotometric method used could have been not enough sensitive to allow the appreciation of differences. At harvest the concentration of non-C6 free-volatiles, particularly terpenes, was significantly higher in the grapes of the HC vineyard.

CONCLUSIONS:

Soil particle size significantly influenced grapevine physiological performances and, consequently, berry quality. At a zonal scale, it is well known that soils with more clay, as the silty-loam HC vineyard, produce grapes giving high-structured wines, whereas sands (or the reduction of clay, such as the LC vineyard) produce less complex wines.

DOI:

Publication date: September 2, 2021

Issue: Macrowine 2021

Type: Article

Authors

Alessandra Ferrandino, Antonio CARLOMAGNO, Giorgio IVALDI, Marco VITALI, Olga KEDRINA, Davide PATONO, Vittorino NOVELLO, Claudio LOVISOLO

University of Turin, Agriproject Group srl, Rutigliano (BA), formerly DISAFA, University of Turin, formerly DISAFA, University of Turin, DISAFA

Contact the author

Keywords

Soil texture, stomatal conductance, anthocyanins, volatiles

Citation

Anthocyanin profile is differentially affected by high temperature, elevated CO₂ and water deficit in Tempranillo (Vitis vinifera L.) clones

Anthocyanin potential of grape berries is an important quality factor in wine production. Anthocyanin concentration and profile differ among varieties but it also depends on the environmental conditions, which are expected to be greatly modified by climate change in the future. These modifications may significantly modify the biochemical composition of berries at harvest, and thus wine typicity. Among the diverse approaches proposed to reduce the potential negative effects that climate change may have on grape quality, genetic diversity among clones can represent a source of potential candidates to select better adapted plant material for future climatic conditions. The effects of individual and combined factors associated to climate change (increase of temperature, rise of air CO2 concentration and water deficit) on the anthocyanin profile of different clones of Tempranillo that differ in the length of their reproductive cycle were studied. The aim was to highlight those clones more adapted to maintain specific Tempranillo typicity in the future. Fruit-bearing cuttings were grown in controlled conditions under two temperatures (ambient temperature versus ambient temperature + 4ºC), two CO2 levels (400 ppm versus 700 ppm) and two water regimes (well-watered versus water deficit), both in combination or independently, in order to simulate future climate change scenarios. Elevated temperature increased anthocyanin acylation, whereas elevated CO2 and water deficit favoured the accumulation of malvidin derivatives, as well as the acylation and tri-hydroxylation level of anthocyanins. Although the changes in anthocyanin profile observed followed a common pattern among clones, such impact of environmental conditions was especially noticeable in one of the most widely distributed Tempranillo clones, the accession RJ43.

Soil quality in Beaujolais vineyard. Importance of pedology and cultural practices

A pedological study was carried out from 2009 to 2017 in Beaujolais vineyard, to improve physical and chemical knowledge of soils. It was completed in 2016 and 2017 by the current study, dealing with microbial aspects, in order to build a reference frame for improved advice in soil management. Microbial biomass was measured on representative plots of the six most common soil types identified in Beaujolais and, for each soil type, on plots with different levels of the main impacting parameters: total organic carbon, pH, cation exchange capacity, extractable copper. A total of 59 soil samples were collected. Confirming the results of various trials carried out in Beaujolais over the past 20 years, the results of the present study showed that the soils were still alive, but exhibited a large variability of biological parameters, which appeared dependant on both pedological and anthropic factors. Therefore, a good interpretation of biological parameters and advice for vine growers must rely on a pedologically-based referential with differentiated main driving factors. For example, the control of pH is of primary importance in granitic soils and in no way organic matter addition can improve soil quality if pH is too low. Conversely, in calcareous soils, biological parameters are more directly affected by direct or indirect (cover crops for example) inputs of organic matter. The use of biological parameters, such as microbial biomass, is of great potential value to improve advice on agro-viticultural practices (soil management, fertilization, liming, etc.), basis of a sustainable wine production on fragile soils.

Influence of climatic conditions on grape composition of Tempranillo in La Mancha DO (Spain)

The aim of this work was to analyze the variability in grape composition of the Tempranillo cultivar related to climatic conditions, in La Mancha Designation of Origin. Grape composition (sugar content, total acidity, pH, malic acid, and total and extractable anthocyanins) recorded during ripening, were analysed for the period 2000-2019. The weather conditions at daily time scale, recorded during the same period, were also evaluated. The relationships between grape parameters with climatic variables related to temperature and to water deficits, referring different periods between phenological events along the growing cycle, were evaluated using regression analysis. High variability in grape composition was observed in the period analysed. Total acidity varied between 3.7 and 7.3 gL-1 while malic acid varied between 1.2 and 4 gL-1. The extractable anthocyanins ranged between 526 and 972 mgL-1, and total anthocyanins ranged between 922 and 1388 mgL-1, being the lowest values recorded in the hottest year (2017). Total acidity decreased 0.77 gL-1 for an increase of 100 GDD, while malic acid decrease in 0.42 gL-1 for the same GDD increase, being the period between veraison and harvest the one that seemed to have higher influence on acidity. In addition, it was confirmed that increasing water deficits decreased acidity. Total and extractable anthocyanins increased in about 210 and 105 mgL-1, respectively, with an increase of 100 GDD from veraison to harvest, and the increase in water deficits favour the increase of anthocyanins, both total and extractable anthocyanins. Total and extractable anthocyanins concentration increased in 35 and 22 mgL-1 per an increase of 10 mm in the water deficit. These results can be of interest to understand the potential changes that grapes composition may suffer under future warmer climates.

Simulating climate change impact on viticultural systems in historical and emergent vineyards

Global climate change affects regional climates and hold implications for wine growing regions worldwide. Although winegrowers are constantly adapting to internal and external factors, it seems relevant to develop tools, which will allow them to better define actual and future agro-climatic potentials. Within this context, we develop a modelling approach, able to simulate the impact of environmental conditions and constraints on vine behaviour and to highlight potential adaptation strategies according to different climate change scenarios. Our modeling approach, named SEVE (Simulating Environmental impacts on Viticultural Ecosystems), provides a generic modeling framework for simulating grapevine growth and berry ripening under different conditions and constraints (slope, aspect, soil type, climate variability…) as well as production strategies and adaptation rules according to climate change scenarios. Each activity is represented by an autonomous agent able to react and adapt its reaction to the variability of environmental constraints. Using this model, we have recently analyzed the evolution of vineyards’ exposure to climatic risks (frost, pathogen risk, heat wave) and the adaptation strategies potentially implemented by the winegrowers. This approach, implemented for two climate change scenarios, has been initiated in France on traditional (Loire Valley) and emerging (Brittany) vineyards. The objective is to identify the time horizons of adaptations and new opportunities in these two regions. Carried out in collaboration with wine growers, this approach aims to better understand the variability of climate change impacts at local scale in the medium and long term.

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.