terclim by ICS banner
IVES 9 IVES Conference Series 9 Effect of partial net shading on the temperature and radiation in the grapevine canopy, consequences on the grape quality of cv. Gros Manseng in PDO Pacherenc-du-vic-Bilh

Effect of partial net shading on the temperature and radiation in the grapevine canopy, consequences on the grape quality of cv. Gros Manseng in PDO Pacherenc-du-vic-Bilh

Abstract

As elsewhere, southwestern France vineyards face more recurrent summer heat waves these last years. Among the possibilities of adaptation to this climate changing parameter, the use of net shading is a technique that allow for limiting canopy exposure to radiations. In this trial, we tested net shading installed on one face of the canopy, on a north-south row-oriented plot of cv. Gros Manseng trained on VSP system in the PDO Pacherenc-du-Vic-Bilh. The purpose was to characterize the effects on the ambient canopy temperatures and radiations during the season and to observe the consequences on the composition of grapes and wines. Two sorts of net were used with two levels of obstruction (50% and 75%) of the photosynthesis active radiation (PAR). They have been installed on the west side of the canopy and compared to a netless control. Temperature and PAR sensors registered hourly data during the season. On specific summer day (hot and sunny) manual measurements took also place on bunches (temperature) and in different spots of the canopy (PAR). The results showed that, on clear days, the radiation is lowered by the shade nets respecting the supplier criteria. The effects on the ambient canopy temperature were inconstant on this plot when we observed the data from the global period of shading between fruit set and harvest. However, during hot days (>30°C), the temperature in the canopy was reduced during afternoon and the temperature of the bunch surface was reduced as well comparing to the control. A decrease of the maturity parameters of the berries, sugar and acidity, was also observed. Concerning the wine aromatic potential, no differences clearly appeared.

Download the PDF

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Thierry Dufourcq1,2, Frédéric Lopez2, Alicia Thomas2, Daniel Vergnes3 and Carole Feilhes1

1IFV Sud-ouest V’Innopole, Lisle/Tarn, France
2IFV Sud-ouest, Château de Mons, Caussens, France3Chambre d’Agriculture des Pyrénées Atlantiques, Pau, France

Contact the author

Keywords

net shading, radiation, temperature, maturity, Gros Manseng

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

European consumer preference for wines made from fungus resistant grape varieties

Fungus resistant grape varieties (FRGV or PIWI) offer many benefits such as less pesticide use or premium prices for enhanced sustainability. Still, winemakers are concerned about inferior wine quality. This study evaluates how European wine consumers assess wines made from new FRGVs in comparison to traditional V. vinifera varieties. Most of them were grown in the same vineyard. Four white (Calardis Blanc, Muscaris, Sauvignac, Cabernet Blanc) und three red (Satin Noir, Cabernet Cortis, Laurot) FRGV were compared to Riesling, Sauvignon blanc, Muskateller, Cab. Sauvignon and Merlot. For each FRGV, different styles were vinified using standardized protocols.

Read More

What about oxygen transfer during wine aging in barrels?

During wine aging, several complex phenomena of gas transfer take place in barrels due to the wine/oak contact. The efficiency of this gas transfer varies according to oak wood’s intrinsic physical properties. This research aims to better understand oxygen transfer phenomena through dry oak staves and especially through stave gaps, in order to reevaluate the importance of barrel-making on a barrel’s supply of oxygen. Experimentation was based on the development of an innovative permeameter of laboratory scale, for which the principal operating conditions concerning applied pressure, the choice of liquid phase/gas phase, and the grain type of oak are taken into account and investigated. With a specially developed tightening system, the existing pressure at stave gaps in a barrel could be reproduced on a laboratory scale in order to estimate its influence on oxygen transfer efficiency.

Read More

The use of remote sensing for intra-block vineyard management

L’unité de gestion technique d’un vignoble est aujourd’hui la parcelle. Néanmoins, au sein d’une même parcelle, la variabilité de l’expression végétative et de la constitution des raisins à maturité, peut être grande, en particulier à cause d’une hétérogénéité du sol.

Read More

Hidden costs of wine: quantifying environmental externalities of organic and integrated management

Agriculture is one of the largest contributors to environmental pollution and causing significant impacts on human health, ecosystems, and resource availability.

Read More

Impact of elemental sulfur (S0) residues in Sauvignon blanc juice on the formation of the varietal thiols 3-mercapto hexanol and 3-mercaptohexyl acetate

Elemental sulfur is a fungicide used by grape growers to control the development of powdery mildew, caused by the fungus Erysiphe necator. This compound is effective, cheap and has a low toxicity with no withholding period recommended. However, high levels of S0 residues in the harvested grapes can lead to the formation of reductive sulfur compounds that can impart taints and faults to the wine. Hydrogen sulphide (H2S) is a very volatile and unpleasant sulfur compound which formation is connected to high residues of S0 in juice (10 – 100 mg/L).

Read More