terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Unveiling a hidden link: does time hold the key to altered spectral signatures of grapevines under drought?

Unveiling a hidden link: does time hold the key to altered spectral signatures of grapevines under drought?

Abstract

Remote sensing technology captures spectral data beyond the visible range, making it useful for monitoring plant stress. Vis-NIR (Visible-Near Infrared) spectroscopy (400-1000 nm) is commonly used to indirectly assess plant status during drought. One example is the widespread use of normalized difference vegetation index (NDVI) that is strongly linked to green biomass. However, a knowledge gap exists regarding the applicability of this method to all the drought conditions and if it is a direct correlation to the water status of the plant.

This study focused on the spectral behavior and physiological changes in leaves of two grapevine cultivars, Riesling and Pinot Noir, that were subjected to different dehydration conditions. Dehydration rates varied from quick to medium and slow, examining the effect of time on the spectral and physiological response. The goal was to determine the potential role of time influencing the consistency of responses across different water dehydration conditions, and if drought stress symptoms could be detected through Vis-NIR analysis. The experimental design included four dehydration treatments: leaf dehydration by (i) detaching the leaves, (ii) cutting the stem from the roots, (iii) removing the soil from the root zone, and (iv) natural dehydration by irrigation withholding. By monitoring the spectral and physiological changes, the study aimed to assess the impact of different dehydration timings and the detectability of associated symptoms. Our results suggest that the timing of dehydration strongly influences the spectral signature changes. In instances under comparable water potentials, plants subjected to fast dehydration (e.g., stem cutting or detached leaves) displayed spectral patterns not significantly different as compared to the ones from adequately hydrated control plants. In contrast, plants undergoing gradual dehydration over several days (e.g., via irrigation withholding) exhibited spectral modifications consistent with previously documented findings.

Acknowledgements: Supported by the Projects DigiPlant and ImStress funded by NÖ Forschungs- und Bildungsges.mbH (NFB), Neue Herrengasse 10, 3rd floor, 3100 St. Pölten, Austria. We sincerely thank Rudi Rizzoli and Soma Laszlo Tarnay for their valuable contributions to the plants management, which played a crucial role in the research project.

DOI:

Publication date: October 3, 2023

Issue: ICGWS 2023

Type: Article

Authors

Flagiello F.1*, Herrera J.C.2, Farolfi E.2, Innocenti J.2, Kulhánková A.3, Bodner G.1

1 Institute of Agronomy, Department of Crop Sciences, University of Natural Resources and Life Sciences Vienna (BOKU), Tulln, Austria
2 Institute of Viticulture and Pomology, Department of Crop Sciences, University of Natural Resources and Life Sciences Vienna (BOKU), Tulln, Austria
3 Department of Horticulture, Faculty of Agrobiology, Food and Natural Resources, The Czech University of Life Sciences Prague, Prague 165 21, Czech Republic.

Contact the author*

Keywords

climate change, hyperspectral analysis, viticulture, drought stress, grapevine

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Implications of the nature of organic mulches used in vineyards on grapevine water status, yield, berry quality and biological soil health  

Climate emergency is going to affect the agricultural suistainability, wine grapes being probably one of the crops more sensitive to environmental constraints. In this context, mitigation strategies such as the revalorization of agricultural wastes are paramount to cope with the current challenges. The use of organic mulches has been reported to reduce soil water evaporation and improve vine water status, reduce soil erosion, and increase soil organic matter with little impact on berry quality. However, less is known about their effects on the microbiote of vineyards.

Agronomic and oenological behavior of the minority Mandón variety on two rootstocks in the D.O. Arribes

A large population of vines of the Mandón minority red variety (synonymous with Garró) has been located in old vineyards of the D.O. Arribes (Zamora and Salamanca) to conserve and recover this minority variety. The wines made with this variety are characterized by their good structure and color, interesting harmony, an excellently low pH, with high acidity, as well as complex aromas of blue fruits and a marked and expressive minerality.

Late winter pruning induces a maturity delay under temperature-increased conditions in cv. Merlot from Chile

Chile is considered vulnerable to climate change; and these phenomena affect several mechanisms in the grape physiology and quality. The global temperature increase affects sugar contents, organic acids, and phenolic compounds in grapes, producing an imbalance maturity. In this sense, an alternative to reduce the impact is to perform pruning after vine budburst, known as “Late Pruning” (LP).

Phenolic composition and chromatic characteristics of blends of cv. Tempranillo wines from vines grown with different viticultural techniques in a semi-arid area

The quality and color stability of red wines are directly related to content and distribution of phenolic compounds. However, the climate change produces the asynchrony between the dates of technological and maturity of grapes. The crop-forcing technique (CF) restores the coupling between phenolic and technological ripeness while limits vineyard yields. Blending of wines is frequently used to equilibriate composition of wines and to increase their stability, color and quality. The aim of the present work is to study the phenolic composition and color of wine blends made with FW (wines from vines subjected to CF) and CW (wines for vines under the usual cultivation practices).

Chemical and microbiological evaluation of Ribeiro wines (NW Spain)

Wine produced under Designation of Origin (DOP) Ribeiro, the oldest DOP in Galicia (NW Spain), are elaborated using local grape cultivars, grown at the valleys of Miño, Avia and Arnoia rivers. The landscape formed by slopes and terraces and the peculiar climate of continental character, softened by the proximity of Atlantic Ocean, make it an area of excellent aptitude for vine cultivation. In addition, small-scale farming and the use of traditional techniques for vineyard management provide a great diversity to Ribeiro wines. This study presents the evaluation of red and white wines (bottled or bulk wines) from DOP Ribeiro, produced between years 2018-2022.