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…

Rootstock effect on Cabernet Sauvignon aromatic and chemical composition

Grape quality potential for wine production is strongly influenced by environmental parameters and agronomic factors. Several studies underline the rootstock effect on scions vegetative growth and berry composition [1] with an impact on wine quality. Rootstocks are promising agronomic tools for climate change adaptation and in most grape-growing regions the potential diversity of rootstocks is not fully used and only a few genotypes are planted. Moreover, little is known about the effect of rootstock genetic variability on the aromatic composition in wines.

The tolerance of grapevine rootstocks to water deficit is related to root morphology and xylem anatomy traits 

Climate change is altering water balances, thereby compromising water availability for crops. In grapevine, the strategic selection of genotypes more tolerant to soil water deficit can improve the resilience of the vineyard under this scenario. Previous studies demonstrated that root anatomical and morphological traits determine vine performance under water deficit conditions. Therefore, 13 ungrafted rootstock genotypes, 6 commercial (420 A, 41 B, Evex 13-5, Fercal, 140 Ru y 110 R), and 7 from new breeding programs (RG2, RG3, RG4, RG7, RG8, RG9 and RM2) were evaluated in pots during 2021 and 2022.

Accumulation of deleterious mutations in grapevine and its relationship with traits of interest for wine production and resilience

Deleterious mutations that severely reduce population fitness are rapidly removed from the gene pool by purifying selection. However, evolutionary drivers such as genetic drift brought about by demographic bottlenecks may comprise its efficacy by allowing deleterious mutations to accumulate, thereby limiting the adaptive potential of populations. Moreover, positive selection can hitchhike mildly deleterious mutations due to linkage caused by lack of recombination. Similarly, in the context of species domestication, artificial selection mimics these evolutionary processes, which can have undesirable consequences for production and resilience. In this study, we evaluated the extent of the accumulation of deleterious mutations and the magnitude of their effects (also known as genetic load) at the whole-genome scale for ca.

Effect of abiotic stress and grape variety on amino acid and polyamine composition of red grape berries

Vines are exposed to environmental conditions that cause abiotic stress on the plants (drought, nutrient and mineral deficits, salinity, etc.). Polyamines are growth regulators involved in various physiological processes, as in abiotic plant stress responses. Stressful conditions can modify grape’s composition, and in this work, we have focused on studying the effect of abiotic stress on the composition of polyamines and amino acids in grapes. In addition, the effect of grape variety on these compounds has been studied.

Preliminary study of extraction of polysaccharides from pomace by high powered ultrasonic combined with enzymes

Red grape pomace can be an important source of polysaccharides, but currently they are little studied and even less with viable and environmental extraction processes (green extraction). These green techniques must be able to break the cell wall so that the compounds contained in the cells, including polysaccharides, are released and can have a great influence on extraction yields, the chemical structure of polysaccharides and applications in wines. Amongst the emerging green techniques most applied to the extraction of bioactive compounds, such as polysaccharides, high-power ultrasound (US) and enzyme-assisted extraction stand out.