terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Energy partitioning and functionality of photosystem II in water-stressed grapevines during heatwaves revealed by continuous measurements of chlorophyll fluorescence

Energy partitioning and functionality of photosystem II in water-stressed grapevines during heatwaves revealed by continuous measurements of chlorophyll fluorescence

Abstract

The increased intensity and frequency of heatwaves, coupled with prolonged periods of drought, are a significant threat to viticulture worldwide. During these conditions the more exposed leaves can show visible symptoms of heat damage. We monitored the functionality of photosystem II (PSII) in the field to better understand the impact of heatwaves on canopy performance. A factorial experiment was established in summer 2023 using Shiraz grapevines in the Barossa valley of South Australia, involving water-stressed and well-watered vines. To monitor the impacts of irrigation and leaf position on PSII functionality, MONI/MICRO PAM heads were mounted on the south (polar facing) and north (equatorial facing) sides of the canopy of each vine. Water stress decreased midday stem water potential (SWP) to -1.4 MPa in water-stressed plants, while well-watered plants maintained SWP at -0.8 MPa. Maximum efficiency of PSII (Fv/Fm) decreased by higher exposure to heat and radiation on the northern side, especially when plants were subjected to water stress. Absorbed energy partitioning in PSII differed between northern and southern sides, and it was influenced by irrigation. At midday, leaves on the southern side showed higher photochemical (Y(II)) and lower non-photochemical yield (Y(NPQ)) than northern leaves. Water stress decreased Y(II) and increased Y(NPQ) at midday predominantly on the northern side. During a heatwave, PSII showed an increase in photoinhibition (Y(NO)) in water-stressed plants on the northern side; however, this effect was reversible and persisted only one day following the heatwave and decreased thereafter to a similar rate to that observed in the rest of the canopy. These findings suggest that, in the short-term, irrigation can be tailored to sustain the canopy during heat waves, while in the medium-term, canopy management strategies (such as shade netting) may be needed to maintain leaf function during and following heatwaves.

DOI:

Publication date: October 5, 2023

Issue: ICGWS 2023

Type: Article

Authors

Walaa Shtai1*, Paul Petrie2, Marcos Bonada3, Massimo Tagliavini1 , Georg Wohlfahrt5, Edwards Everard4

1Free University of Bolzano- Bozen, Italy
2South Australian Research and Development Institute (SARDI), Adelaide, Australia
3Treasury Wine Estates, Adelaide, Australia.
4CSIRO Agriculture and Food, Adelaide, Australia
5University of Innsbruck, Austria

Contact the author*

Keywords

chlorophyll fluorescence, heat stress, water stress, grapevines, energy partitioning, heat dissipation, photoinhibition

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Model-assisted analysis of the root traits underlying RSA genotypic diversity in Vitis: a promising approach for rootstock selection?

By dissecting the root system architecture (RSA) into its underpinning components (e.g. root emission, axial growth, radial growth, branching, root direction or tropism) and identifying the relationships between them, functional-structural 3D root models are promising tools for analyzing the diversity and complexity of root system phenotypes with Genotype × Environment interactions. The model parameters are assumed to be synthetic traits, less influenced by the environment, and consequently with less polygenic architectures than the integrative RSA traits they drive. Root models can serve as a basis for in silico development of root system ideotypes by highlighting the developmental processes and parameters that most likely influence RSA fitness.

Read More

Combined use of leaf removal and natural shading to delay grape ripening in Manto negro (Vitis vinifera L.) under deficit irrigation 

The increasingly frequent heat waves during grape ripening pose challenges for premium wine grape production. This makes the development of irrigation and canopy management techniques of great importance to maximize yield and grape quality. A field experiment was carried out during 2021 and 2022 using Manto negro wine grapes to study the effect of two irrigation strategies and different light exposure levels on grape quality.

Read More

Characterization of spoilage yeasts from Malbec grapes from San Rafael wine region (Argentina)

The yeast ecosystem in grape musts is quite broad and depends on the region and the health of the grapes. Within this, there are yeasts that can generate fermentative deviations and/or cause defects in the wine. It is very important to address this issue because there are significant economic losses in the wine industry when the fermentation process and/or the organoleptic characteristics of the wine are negatively affected, even more today since climate change has a marked effect on the composition of this ecosystem. The aim of this work is to characterize the behavior regarding detrimental oenological features of potential spoilage yeasts isolated from viticultural environments.

Read More

Chemical profiling and sensory analysis of wines from resistant hybrid grape cultivars vs conventional wines

Recently, there has been a shift toward sustainable wine production, according to EU policy (F2F and Green Deal), to reduce pesticide usage, improve workplace health and safety, and prevent the impacts of climate change. These trends have gained the interest of consumers and winemakers. The cultivation of disease resistant hybrid grape cultivars (DRHGC), known as ‘PIWI’ grapes can help with these objectives [1]. This study aimed to profile white and red wines produced from DRHGC in South Tyrol (Italy). Wines produced from DRHGCs were compared with conventional wines produced by the same wineries. The measured parameters were residual sugars, organic acids, alcohol content, pigments and other phenolics by LC-QqQ/MS, colorimetric indexes (CIELab); and volatile profiles (HS-SPME-GCxGC-ToF/MS [2]).

Read More

Applicability of spectrofluorometry and voltammetry in combination with machine learning approaches for authentication of DOCa Rioja Tempranillo wines

The main objective of the work was to develop a simple, robust and selective analytical tool that allows predicting the authenticity of Tempranillo wines from DOCa Rioja. The techniques of voltammetry and absorbance-transmission and fluorescence excitation emission matrix (A-TEEM) spectroscopy have been applied in combination with machine learning (ML) algorithms to classify red wines from DOCa Rioja according to region (Alavesa, Alta or Oriental) and category (young, crianza or reserva).

Read More