terclim by ICS banner
IVES 9 IVES Conference Series 9 Mobile device to induce heat-stress on grapevine berries

Mobile device to induce heat-stress on grapevine berries

Abstract

Studying heat stress response of grapevine berries in the field often relies on weather conditions during the growing season. We constructed a mobile heating device, able to induce controlled heat stress on grapes in vineyards. The heater consisted of six 150 W infrared lamps mounted in a profile frame. Heating power of the lamps could be controlled individually by a control unit consisting of a single board computer and six temperature sensors to reach a pre-set temperature. The heat energy applied to individual berries within a cluster decreases by the squared distance to the heat source, enabling the establishment of temperature profiles within individual clusters. These profiles can be measured by infrared thermography once a steady state has been reached. Radiant flux density received by a berry depending on the distance was calculated based on a view factor and measured lamp surface temperature and resulted to 665 Wm-2 at 7cm. Infrared thermography of the fruit surface was in good agreement with measurements conducted with a thermocouple inserted at epidermis level. In combination with infrared thermography, the presented device offers possibilities for a wide range of applications like phenotyping for heat tolerance in the field to proceed in the understanding of the complex response of plants to heat stress. Sunburn necrosis symptoms were artificially induced with the aid of the device for cv. Bacchus and cv. Sylvaner in the 2020 and 2021 growing season. Threshold temperatures for sunburn induction (LT5030min) were derived from temperature data of single berries and visual sunburn assessment, applying logistic regression. A comparison of threshold temperatures for the occurrence of sunburn necrosis confirmed the higher susceptibility of cv. Bacchus. The lower susceptibility of cv. Sylvaner did not seem to be related to its phenolic composition, rendering a thermoprotective role of berry phenolic compounds unlikely.

Download the PDF

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Kai Müller, Manfred Stoll, Marco Hoffmann and Matthias Friedel

Hochschule Geisenheim University, Department of General and Organic Viticulture, Geisenheim, Germany

Contact the author

Keywords

fruit surface temperature, heat-stress, sunburn, thermography, Vitis vinifera

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

Simulated climate change in a Mediterranean organic vineyard altered the plant physiology and decreased the vine production

This study focuses on investigating the effects of climate change on the plant physiology and berries of Vitis vinifera cv “Monastrell” in a commercial vineyard managed organically in Southeastern Spain (Jumilla, Murcia). For this purpose, open top chambers and rainout shelters were employed to simulate warming (~2-7 ºC, W) and rainfall reduction (~30%, RR) respectively. Additionally, a combination of both treatments (W+RR) was employed. Vines without either top chambers or rainout shelters were considered as control (C). The experiment was established in February of 2023. Predawn leaf water potential (measured using a pressure chamber), stomatal conductance (assessed with a porometer at mid-morning) and leaf chlorophyll and flavonoid content (measured using the Dualex® leaf clip sensor) were analyzed at veraison (5 months after the installation of structures).

Read More

High-resolution aerial thermography for water stress estimation in grapevines

Aerial thermography has emerged as a promising tool for water stress detection in grapevines, but there are still challenges associated with this technology, particularly concerning the methodology employed to extract reliable canopy temperature values. This consideration is relevant especially in vertically trained vineyards, due to the presence of multiple surfaces which are captured by drone thermal cameras with high-resolution. To test the technology and the data analysis required, a field study was conducted during the 2022-2023 season in a model vineyard with multiple scions-rootstock combinations trained on a vertical shoot-positioning (VSP) system. Additionally, three irrigation regimes were implemented to introduce variability in water stress levels.

Read More

Apports des mesures de résistivité électrique du sol dans les études sur le fonctionnement de la vigne et dans la spatialisation parcellaire

La mesure de la résistivité électrique des sols est une technique non destructive, spatialement intégrante, utilisée depuis peu en viticulture. L’utilisation d’appareils de mesures performant et de logiciels adaptés permet de traiter les données afin de pouvoir visualiser en deux ou trois dimensions les variations de textures ou d’humidité d’un sol.

Read More

Biosynthetic evolution of galloilated polyphenols in Tannat grapes during ripening, potential applications of grape thinning

Galloylated flavan-3-ols are a class of polyphenolic compounds present in various plants, including grape seeds. These compounds are formed through the condensation of flavan-3-ols, such as catechins, although the precise mechanism by which gallic acid is incorporated into the molecule remains unclear.

Read More

Adaptation et expression de l’encépagement et mode de conduite en différents terroirs de la région du Douro/vin de Porto

Ce travail a pour objet l’analyse des résultats agronomiques obtenus sur trois unités expérimentales du Centre d’Etudes Vitivinicoles du Douro (CEVDouro), localisées dans des écosystèmes différenciés de la Région du Douro/Vin de Porto, à différentes altitudes (130, 330 et 520 mètres) et à des expositions diversifiées (SE, N et W).

Read More