 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

Adaptability of grapevines to climate change: characterization of phenology and sugar accumulation of 50 varieties, under hot climate conditions

Climate is the major factor influencing the dynamics of the vegetative cycle and can determine the timing of phenological periods. Knowledge of the phenology of varieties, their chronological duration, and thermal requirements, allows not only for the better management of interventions in the vineyard, but also to predict the varieties’ behaviour in a scenario of climate change, giving the wine producer the possibility of selecting the grape varieties that are best adapted to the climatic conditions of a certain terroir. In 2014, Symington Family Estates, Vinhos, established two grape variety libraries in two different places with distinctive climate conditions (Douro Superior, and Cima Corgo), with the commitment of contributing to a deeper agronomic and oenological understanding of some grape varieties, in hot climate conditions. In these research vineyards are represented local varieties that are important in the regional and national viticulture, but also others that have over time been forgotten — as well as five international reference cultivars. From 2017 to 2021, phenological observations have been made three times a week, following a defined protocol, to determine the average dates of budbreak, flowering and veraison. With the climate data of each location, the thermal requirements of each variety and the chronological duration of each phase have been calculated. During maturation, berry samples have been gathered weekly to study the dynamics of sugar accumulation, between other parameters. The data was analysed applying phenological and sugar accumulation models available in literature. The results obtained show significant differences between the varieties over several parameters, from the chronological duration and thermal requirements to complete the various stages of development, to the differences between the two locations, confirming the influence of the climate on phenology and the stages of maturation, in these specific conditions.

A better understanding of the climate effect on anthocyanin accumulation in grapes using a machine learning approach

The current climate changes are directly threatening the balance of the vineyard at harvest time. The maturation period of the grapes is shifted to the middle of the summer, at a time when radiation and air temperature are at their maximum. In this context, the implementation of corrective practices becomes problematic. Unfortunately, our knowledge of the climate effect on the quality of different grape varieties remains very incomplete to guide these choices. During the Innovine project, original experiments were carried out on Syrah to study the combined effects of normal or high air temperature and varying degrees of exposure of the berries to the sun. Berries subjected to these different conditions were sampled and analyzed throughout the maturation period. Several quality characteristics were determined, including anthocyanin content. The objective of the experiments was to investigate which climatic determinants were most important for anthocyanin accumulation in the berries. Temperature and irradiance data, observed over time with a very thin discretization step, are called functional data in statistics. We developed the procedure SpiceFP (Sparse and Structured Procedure to Identify Combined Effects of Functional Predictors) to explain the variations of a scalar response variable (a grape berry quality variable for example) by two or three functional predictors (as temperature and irradiance) in a context of joint influence of these predictors. Particular attention was paid to the interpretability of the results. Analysis of the data using SpiceFP identified a negative impact of morning combinations of low irradiance (lower than about 100 μmol m−2 s−1 or 45 μmol m−2 s−1 depending on the advanced-delayed state of the berries) and high temperature (higher than 25oC). A slight difference associated with overnight temperature occurred between these effects identified in the morning.

Downscaling of remote sensing time series: thermal zone classification approach in Gironde region

In viticulture, the challenges of local climate modelling are multiple: taking into account the local environment, fine temporal and spatial scales, reliable time series of climate data, ease of implementation and reproducibility of the method. At the local scale, recent studies have demonstrated the contribution of spatialization methods for ground-based climate observation data considering topographic factors such as altitude, slope, aspect, and geographic coordinates (Le Roux et al, 2017; De Rességuier et al, 2020). However, these studies have shown questions in terms of the reproducibility and sustainability of this type of climate study. In this context, we evaluated the potential of MODIS thermal satellite images validated with ground-based climate data (Morin et al, 2020). Previous studies have been encouraging, but questions remain to be explored at the regional scale, particularly in the dynamics of the massive use of bioclimatic indices to classify the climate of wine regions. The results at the local scale were encouraging, but this approach was tested in the current study at the regional scale. Several objectives were set: 1) to evaluate the downscaling method for land surface temperature time series, 2) to identify regional thermal structure variations. We used weekly minimum and maximum surface temperature time series acquired by MODIS satellites at a spatial resolution of 1000 m and downscaled at 500 m using topographical variables. Two types of analyses were performed:

Mesoclimate impact on Tannat in the Atlantic terroir of Uruguay

The study of climate is relevant as an element conditioning the typicity of a product, its quality and sustainability over the years. The grapevine development and growth and the final grape and wine composition are closely related to temperature, while climate components vary at mesoscale according to topography and/or proximity to large bodies of water. The objective of this work is to assess the mesoclimate of the Atlantic region of Uruguay and to determine the effect of topography and the ocean on temperature and consequently on Tannat grapevine behavior.

A multidisciplinary approach to evaluate the effects of the training system on the performance of “Aglianico del Vulture” vineyards

Vineyards are complex agro-ecosystems with high spatial and temporal variability. An efficient training system may counteract the adverse effects of this variability. Moreover, considering the climate change issues, choosing an efficient training system that enhances water use and protects the vines from radiative thermal stress has become a priority for the farmers. A multidisciplinary approach that assesses the soil-crop-yield-wine relationships of vineyards in a distributed and holistic way could bring added knowledge on the behavior of the different training systems. This ongoing research aimed to implement a multidisciplinary approach to study the behavior of “Aglianico del Vulture” grapevines trained with two different systems: a spurred cordon (SC) and an “Alberello in parete” (AL), grown in a high-quality wine production area of Basilicata region (Italy). The approach merged several methods and scales of soil, ecophysiology, must/wine quality, and spectral data collection to assess the influence of the training system. Homogeneous zones (HZs) in both training systems were defined through a procedure based on geomorphological classification, unmanned aerial vehicles (UAV) images analysis, and a traditional soil survey supported by geophysical scanning. During the 2021 season, TDR probes monitored soil water content, while grapevine health status was assessed using eco-physiological measurements (LWP, chlorophyll content, PSII photosynthetic efficiency, LAI, and point-based field spectroscopy). These grapevine in-vivo measurements validated the spectral vegetation indexes (NDVI, RENDVI, CVI, and TVI) derived from the UAV multispectral imagery, which monitored the grapevine status in a distributed and non-invasive way. Grape yield, quality of berries, must and wine were measured to assess the effects of the training systems. The first experimental year results showed the variability of the vineyards and revealed relationships among soil parameters, crop characteristics, and vegetation indices of the SC and AL training systems. This multidisciplinary study could bring new insights into the vineyard training system’s effects on grape yield and wine quality.