terclim by ICS banner
IVES 9 IVES Conference Series 9 Techniques for sunburn reduction in bunches in Vitis vinifera L. cv. Graciano

Techniques for sunburn reduction in bunches in Vitis vinifera L. cv. Graciano

Abstract

Sunburn results from a combination of excessive photosynthetically active radiation (PAR) and UV radiation and temperature that can be exacerbated by other stress factors such as water deficit. Sunburn is a physiological disorder that affects the visual and organoleptic properties of grapes. The appearance of brown and necrotic spots severely affects the commercial value of the fruit, and in extreme cases, significantly decreases yield.  This damage occurs with some frequency in sensitive varieties such as Graciano. In order to mitigate these impacts, a shading technique has been proposed using protection nets that try to prevent the bunches from receiving excessive sun exposure. The experience shown in this work has been carried out during the years 2021 and 2022, using nets with shading capacity of 50% and 70%, and in 2023 using nets with 25% and 50% with shading capacity. The results have shown that the nets have significantly reduced the temperature of the bunch, also avoiding damage from sunburn. Besides, the organic acid content of the must has reached slightly higher values in the treatments with netting, compared to the control, but not significantly. In wine, the polyphenolic load has shown a variable behavior depending on the year, possibly conditioned by the variations in yield linked to the sunburn. The tasting panel has shown a certain inclination towards the wines from the net treatments.

DOI:

Publication date: June 14, 2024

Issue: Open GPB 2024

Type: Poster

Authors

Luis Rivacoba*, Javier Portu, Sergio Ibáñez

Instituto de Ciencias de la Vid y del Vino (Gobierno de La Rioja, Universidad de La Rioja, CSIC). Finca La Grajera, Ctra. de Burgos Km. 6, Logroño, La Rioja 26007, Spain

Contact the author*

Keywords

sunburn, shading, Graciano

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Traditional agroforestry vineyards, sources of inspiration for the agroecological transition of viticulture

A unique “terroir” can be found in southern Bolivia, which combines the specific features of climate, topography and altitude of high valleys, with the management of grapevines staked on trees. It is one of the rare remnants of agroforestry viticulture. A survey was carried out among 29 grapegrowers in three valleys, to characterize the structure and management of these vineyards, and identify the services they expect from trees. Farms were small (2.2 ha on average) and 85% of vineyards were less than 1 ha. Viticulture was associated with vegetable, fruit and fodder production, sometimes in the same fields. Molle trees were found in all plots, together with one or two other native tree species. Traditional grapevine varieties such as Negra Criolla, Moscatel de Alejandría and Vicchoqueña were grown with a large range of densities from 1550 to 9500 vines ha-1. From 18 to 30% of them were staked on trees, with 1.2 to 4.9 vines per tree. The management of these vineyards (irrigation, fertilization and grapevine protection) was described, the most particular technical operation being the coordinated pruning of trees and grapevines. Three types of management could be identified in the three valleys. Grapegrowers had a clear idea of the ecosystem services they expected from trees in their vineyards. The main one was protection against climate hazards (hail, frost, flood). Then they expected benefits in terms of pest and disease control, improvement of soil fertility and resulting yield. At last, some producers claimed that tree-staking was quicker and cheaper than conventional trellising. It can be hypothesized then that agroforestry is a promising technique for the agroecological transition of viticulture. Its contribution to the “terroir” of the high valleys of southern Bolivia and its link with the specificities of the wines and spirits produced there remain to be explored.

Terroir effects on the response of Tempranillo grapevines to irrigation in four locations of Spain: agronomic performance and water relations

We report the effects of different drip irrigation treatments on the agronomic performance and water relations of Tempranillo grapevines, pruned to a bilateral cordon

Il piano regolatore delle citta’ del vino: una metodologia di lavoro

Sono quattro i terni fondamentali di questo progetto: la sostenibilità; la conoscenza; la parte­cipazione come strumento anche di riduzione della burocrazia e il tema della coerenza delle politiche di settore e della collaborazione fra gli Enti.

Comparison of aroma-related compounds of carbonic maceration and traditional young red winemaking in case of Merlot by means of targeted metabolomic approach

Winemaking decisions and techniques are known to affect the final aromatic composition of red wines. Winemakers put a constant effort into the improved controlling of vinification procedures to achieve better quality. Anyway an increased customer’s demand for uniqueness is often forcing them to adjust and offer new and new interesting products. To support the producers, an improved knowledge on aromatic potential as affected by classical and alternative strategies is needed.

Integrated multiblock data analysis for improved understanding of grape maturity and vineyard site contributions to wine composition and sensory domains

Much research has sought to define the complex contribution of terroir (varieties x site x cultural practices) on wine composition. This investigation applied recent advances in chemometrics to determine relative contributions of vine growth, berry maturity and site mesoclimate to wine composition and sensory profiles of Shiraz and Cabernet Sauvignon for two vintages.