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…

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

Grape and wine phenolic compounds have been shown to be highly related to both wine quality (color, flavor, and taste) and health-promoting properties (antioxidant and cardioprotective, among others). The aim of this work was to evaluate and compare the phenolic contents of Cabernet Sauvignon wines from different geographical areas and climatic conditions, namely from Argentina, Portugal and Spain vintage 2022. In addition, the phenolic profiles of the Portuguese wines from three vintages (2020, 2021, 2022) was compared.

Ecophysiological characterisation of terroir effects on Vitis vinifera L. Chardonnay and pinot noir in south african cool climate regions

Terroir encompasses environmental (climate, geology, soil and topography), genetic (cultivar and clone) and human factors (oenological and viticultural practices). Climate change brings about shifts in the suitability of a region for the growth of specific grapevine cultivars. This study focused on climatic and fruit parameters (berry size, weight, pH, total acidity (TA) and phenolics) to characterise the terroir effect in Vitis vinifera L. cultivars Chardonnay and Pinot Noir vineyards in the Cape South Coast region (Walker Bay and Elgin).

Sensory profile of wines obtained from disease-resistant varieties in La Rioja

The European wine industry is facing multiple challenges derived from climate change and the pressure of different fungal diseases that are compromising the production of traditional varieties. A sustainable alternative maybe the adoption of resistant varieties.
In this study, we have evaluated the enological potential of 9 resistant varieties (5 white and 4 red varieties) in La Rioja. Microvinifications were carried out with three biological replications. Oenological parameters were very diverse with acid content varying from 2.6 g/L to 6.6 g/L.

Effects of laccase from Botrytis cinerea on the oxidative degradation kinetics of the five natural grape anthocyanins

Enzymatic browning[1] is an oxidation process that occurs in many foods that increases the brown colour[2]. This problem is especially harmful in the wine industry[3]. especially when the grapes are infected by grey rot since this fung release the oxidative enzyme laccase[4]. In the particular case of red wines, the presence of laccase implies the deterioration of the red colour and can even cause the precipitation of the coloring matter (oxidasic haze)[5].

Possible methods of adaptation to the effects of climate change in the Tokaj Wine Region 

Viticulture’s adaptation to the harmful effects of climate change is globally the biggest challenge of the near future. Short, extremely intensive rainfalls and longer periods of drought are getting more frequent in the Tokaj Wine Region, where the majority of the vineyards are cultivated on steep slopes. Hence, erosion has high risk, especially when combined with the loess-based soils on about ten percent of the region. The environmentally beneficial cover crop and mulch usage can effectively reduce the risk of erosion, according to research done by the Tokaj Wine Region Research Institute of Viticulture and Oenology.