GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 Colored hail‐nets as a tool to improve vine water status: effects on leaf gas exchange and berry quality in Italia table grape

Colored hail‐nets as a tool to improve vine water status: effects on leaf gas exchange and berry quality in Italia table grape

Abstract

Context and purpose of the study ‐ Protecting table grape vineyards with white hail‐nets is a common practice in Southern Italy. Hail‐nets result in shading effects of 10‐20 %, depending on their density and type of weave, thus they act as a low shading nets and modify the vineyard microclimate. Darker nets are more opaque to solar radiation, increasing the shading effects. Colored nets have been introduced in horticultural crops aiming to alter the amount and composition of light available at canopy level, in order to getparticular light‐induced effects on microclimate, plant physiology, growth and production. Yellow and red nets are among the most studied. However, by now, results of different studies are not always consistent with each other. The present study aimed at assessing the performance of Italia table grape grapevine under yellow and red hail‐nets, with a particular interest to the chance of modulating the microenvironment to support the vine water status under the semi‐arid conditions of Southern Italy, evaluating also the effects exerted on the grape quality.

Material and methods ‐ The study was run in 2014 and 2015, in the BT province of Apulia region, on Italia covered with white, yellow and red nets, all having mesh of about 3×5 mm. PAR, air temperature and RH were monitored in warm hours of typical days of mid‐ and late‐ July and August. Leaf gas exchange and stem water potentials were measured. Leaf area was assessed ceptometrically. At harvest, berry fresh weight, skin color, juice total soluble solid concentration (TSS) and titratable acidity (TA), main skin and pulp phenol contents, and berry antioxidant activity (AA) were determined.

Results – Respect to the white net,the colored ones reduced the PAR available for canopy (especially the red net) and increased air temperature and RH (especially the yellow net). On average, they lowered the air VPD along the canopy profile by ~10% and improved the vine water status from 33 % (yellow net) to 38 % (red net). However, this improvement did not enhance the leaf gas exchange measured at maximum PAR 2 interception (~1450 ~mol/m /s); on the contrary, the leaf transpiration, and even more the net CO2 uptake, tent to be lowered by yellow net, but not, or at a little extent, by the red net. The leaf area did not change. According to literature, yellow color depresses the transmissivity of red and blue wavelengths, active on photoreceptors that stimulate stomata opening and PSII efficiency. At harvest, on average, the patterns of berry and bunch weight were similar to those of leaf gas exchange (especially to the transpiration one); the yellow component of the skin color decreased with both colored nets; the TSS/TA ratio increased. The skin phenol contents were lowered by the red net but not, or a very little extent, by the yellow one; the berry antioxidant activity progressively decreased passing from the white to the yellow and to the red net. In conclusion, under the trial conditions, the yellow and red hail‐nets did not influence the performance of Italia grapevine in univocal way. Some responses seemed more related to their low shading effects, while others to their spectrometric effects. They rose significantly the vine water status compared to the white net, but this improvement did not enhance other physiological parameters or any berry quality attributes.

 

DOI:

Publication date: June 22, 2020

Issue: GiESCO 2019

Type: Article

Authors

Laura de PALMA (1), Patrizio LIMOSANI (1), Vittorino NOVELLO (2)

(1) University of FOGGIA-SAFE, Via Napoli 25, I-71122, Foggia, Italy
(2) University of Turin-DiSAFA, Largo Braccini 2, I-10095, Grugliasco (TO), Italy

Contact the author

Keywords

Grapevine, Microenvironment, Ecophysiology, Maturity indices, Phenol contents, Berry antioxidant activity

Tags

GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Towards adaptation to climate change in Rioja: Quality evaluation of wines obtained from Grenache x Tempranillo selections

The wine sector is of great relevance and tradition in Mediterranean countries, however, it may be most susceptible to climate change. In recent years, wine production is facing changes worldwide, both at environmental as well as commercial levels, due to global warming and the shift in consumers’ preferences. Wine growers and wine makers are in search of solutions that allow to face these new challenges. One of the most promising initiatives in the long term is the introduction of new plant materials, specifically intraspecific hybridizations between premium varieties that may improve traditional germplasm in its adaptation to climate change. These inter-varietal crosses have the potential to generate quality wines, whilst maintaining the regional typicity, and constitute an attractive alternative for the consumer due to their sensory attributes. In this study, we have evaluated wines from 29 intraspecific Garnacha x Tempranillo hybrids in two different locations, with the aim to assess their oenological potential and sensory attributes. Thirteen of the selections were white and 16 were red. Microvinifications were conducted with two or three replications depending on grape availability. Conventional oenological parameters were determined for all wines. The sensory evaluation and hedonic scores were given by five experts. Red selections obtained higher quality scores than white ones. Among the white selections with higher quality scores, GT-41 Varea and GT-159 Varea outstand, due to their high total acidity and high malic acid content. Regarding red selections, GT-57 Varea and GT-57 UR were perceived as higher in quality, highlighted for their moderate alcoholic and high anthocyanin content. Our results indicate that intraspecific hybridization may be a powerful tool for adapting traditional cultivars to climate change in Rioja.

Effects of graft quality on growth and grapevine-water relations

Climate change is challenging viticulture worldwide compromising its sustainability due to warmer temperatures and the increased frequency of extreme events. Grafting Vitis vinifera L.

How can historical cultivars mitigate the effects of climate change?

IFV, INRAe and the national network “Partenaires de la Sélection Vigne” representing 37 organizations from the different wine regions, have been working increasingly closely over the last 2 decades towards the preservation of the French varietal patrimony. There are approximately 600 patrimonial varieties according to INRAe and SupAgro Montpellier experts, including ancient cultivars (400) and intravarietal crossbreeds obtained since the 19th century. In the context of a drastic reduction in such varieties from the mid 1980’s in favor of mainstream varieties, it was essential to carry out an inventory of old vines and vineyards. INRAe Vassal collection plays a key role here as it holds the largest diversity available, along with a rich bibliography and herbariums, offering us the opportunity to document and double check the identity of a cultivar, consolidating the expertise of ampelographers. The work is carried out in several stages, from verifying the existence of a variety in a small region, through to rehabilitation. During this session, the authors present the process that leads to the official registration of a variety. After this, IFV selection center takes over to initiate the process of selection and propagation. A specific focus within regions such as the Alps, Champagne and the South-West will provide details of the full procedure. Bia, Bouysselet, Chardonnay rose, Mecle and the aptly named Tardif, are some of the cultivars that have followed this procedure. Furthermore, a recent regulation established by INAO on “varieties of interest for adaptation purposes” might boost uptake by growers. Since 2006, 36 historical cultivars have been registered. Most of these have been neglected in the past due to late maturity, lack of sugar and high titratable acidity at harvest time. Such characteristics are today considered as positive qualities, not only in mitigation of the effects of climate change, but also as an opportunity for restoring diversity…

Phenological characterization of a wide range of Vitis Vinifera varieties

In order to study the impact of climate change on Bordeaux grape varieties and to assess the adaptation capacities of candidates to the grape varieties of this wine region to the new climatic conditions, an experimental block design composed of 52 grape varieties was set up in 2009 at the INRAE Bordeaux Aquitaine center. Among the many parameters studied, the three main phenological stages of the vine (budburst, flowering and veraison) have been closely monitored since 2012. Observations for each year, stage and variety were carried out on four independent replicates. Precocity indices have been calculated from the data obtained over the 2012-2021 period (Barbeau et al. 1998). This work allowed to group the phenological behaviour of the grapevine varieties, not only based on the timing of the subsequent developmental stages, but also on the overall precocity of the cycle and the total length of the cycle between budburst and veraison. Results regarding the variability observed among the different grape varieties for these phenological stages are presented as heat maps.

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"...