terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 The influence of pre-heatwave leaf removal on leaf physiology and berry development

The influence of pre-heatwave leaf removal on leaf physiology and berry development

Abstract

Due to climate change, the occurrence of heatwaves and drought events is increasing, with significant impact on viticulture. Common ways to adapt viticulture to a changing climate include site selection, genotype selection, irrigation management and canopy management. The latter mentioned being for instance source-sink manipulations, such as leaf removal, with the aim to delay ripening.

However, there is limited knowledge on how leaf removal influences water relations, especially when applied immediately before a heatwave. The purpose of this study is to investigate how leaf removal (reducing the total leaf area by 30 % in the apical part of the canopy) influences leaf physiology and berry quality under multiple abiotic stress conditions. Using climate chambers that allow a fine control of the climatic conditions, a 5-day heatwave with maximum temperature of 40 °C will be simulated. The factorial experiment includes two levels of soil water availability (irrigated, drought stressed) and two levels of defoliation (defoliated, not defoliated) with the intention to determine how pre-heatwave leaf removal influences (I) the usage of water under heat and drought conditions, (II) leaf physiological performance (gas exchange, photosystem efficiency), as well as (III) berry development and quality (yield, chemical composition and berry mechanical properties). Our hypothesis is that, by significantly reducing the leaf area (i.e. water transpiring surface) before a heatwave, fewer irrigation water is needed to maintain a favorable water status. The experiment is currently ongoing (summer 2023), therefore we cannot provide preliminary results at this stage. Nevertheless, with our results we hope to validate leaf removal a new and easy to implement short-term adaption strategy to make viticulture more resilient in the context of climate change.

DOI:

Publication date: October 9, 2023

Issue: ICGWS 2023

Type: Poster

Authors

Mario Wegher1, 2*, Georg Niedrist2, Massimo Tagliavini1, Carlo Andreotti1

1Faculty of Agricultural, Environmental and Food Sciences, Free University of Bozen-Bolzano, Bolzano, Italy
2Institute for Alpine Environment, European Academy of Bolzano/Bozen, Drususallee 1, Bolzano, 39100, Italy

Contact the author*

Keywords

grapevine, drought stress, heat stress, leaf removal, berry quality

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Retrospective analysis of our knowledge regarding the genetics of relevant traits for rootstock breeding 

Rootstocks were the first sustainable and environmentally friendly strategy to cope with a major threat for Vitis vinifera cultivation. In addition to providing Phylloxera resistance, they play an important role in protecting against other soil-borne pests, such as nematodes, and in adapting V. vinifera to limiting abiotic conditions. Today viticulture has to adapt to ongoing climate change whilst simultaneously reducing its environmental impact. In this context, rootstocks are a central element in the development of agro-ecological practices that increase adaptive potential with low external inputs. Despite the apparent diversity of the Vitis genus, only few rootstock varieties are used worldwide and most of them have a very narrow genetic background. This means that there is considerable scope to breed new, improved rootstocks to adapt viticulture for the future.

Vineyard yield estimation using image analysis: assessing bunch occlusions and its dependency on fruiting zone canopy features

Performing accurate vineyard yield estimation is of upmost importance as it provides important benefits to the whole vine and wine industry. Recently, image-analysis approaches have been explored to address this issue however this approach has as main challenge the bunch occlusion, mostly by vegetation but also by neighboring bunches. The present work aims at assessing the magnitude of bunch occlusion by neighboring bunches and to evaluate its dependency on a selection of vegetative and reproductive vine parameters assessed at fruiting zone. Forty vine segments (1 m) of two vineyard plots of the white cultivars ‘Alvarinho’ and ‘Arinto’ were assessed for vegetative and reproductive features at fruiting zone and imaged with a 2D camera.

Perception, liking and emotional response of tropical fruit aromas in Chardonnay wines

Tropical fruit aromas in wines are thought to be important to wine consumers, although there is little research to confirm this statement. With so many wine styles available, it has become important to understand the qualities that are desirable to consumers and how to achieve those qualities. Thiols and esters are compounds that have been found to cause tropical fruit aromas in chardonnay (ref). Fermentation temperature gradients and skin contact were found to increase these compounds using micro scale fermentations. This work aimed to scale up these fermentations/operations to determine if the desired tropical fruit aromas could still be achieved and if there is a perceivable difference in tropical fruit aromas, liking, and emotional response in the wines at the consumer level.

Organic mulches slightly influence wine phenolic composition and sensorial properties

Grapevines have traditionally been grown in semi-arid areas, but viticulture is now compromised by climate change. Therefore, it is necessary to implement environmentally friendly viticulture practices to adapt grapevines to current climatic conditions. In this context, organic mulches offer many benefits, such as reduced soil erosion and increased organic matter, soil water content and crop productivity. However, these practices must not compromise grape and wine quality. Therefore, the objective of this study was to evaluate the effect on wine physicochemical and phenolic composition and sensorial properties of different soil management practices on the vine row. Over four years, five soil treatments were examined in two different vineyards.

Volatile composition of Cabernet Sauvignon wines from Argentina, Portugal and Spain

Cabernet Sauvignon is one of the most cultivated grape varieties worldwide being grown in different environmental conditions due to its excellent adaptability. Volatile compounds deeply contribute to the sensory properties of wines therefore to wine quality. The aim of this work was to compare the aroma profile of Cabernet Sauvignon wines from different geographical areas and climatic conditions, namely from Argentina, Portugal and Spain, from the vintage 2022. In addition, the volatile composition of the Cabernet Sauvignon Portuguese wines from three vintages was evaluated.