Terroir 2020 banner
IVES 9 IVES Conference Series 9 International Terroir Conferences 9 Terroir 2020 9 History and innovation of terroir 9 Prospects of thermal imaging as a non-invasive tool to assess water status for irrigation scheduling in commercial vineyards

Prospects of thermal imaging as a non-invasive tool to assess water status for irrigation scheduling in commercial vineyards

Abstract

Aim: Irrigated viticulture is expanding worldwide mainly as a short-term adaptation strategy to climate change. Plant-based methods are increasingly being used for irrigation scheduling in commercial vineyards. Canopy temperature (TC) has long been recognized as an indicator of plant water status. TC, but also the thermal stress indices, e.g. crop water stress index (CWSI) and stomatal conductance index (IG) have been used to support and manage irrigation in several crops including grapevine. The goal of this work was to review thermal imaging as non-invasive tool to assess water status in commercial vineyards in Rioja (Spain) and in the wine regions of Douro and Alentejo (Portugal). 

Methods and Results: Thermal cameras were used as ground based portable sensors to manually assess water status. Significant correlations between TC and/or thermal indices and stomatal conductance or stem water potential (Ψstem) were observed in the vineyards of these top wine regions. Recently, a thermal camera was also mounted in an all-terrain-vehicle for the on-the-go acquisition of thermal images. TC, CWSI and IG were significantly correlated to Ψstem at both canopy sides. Water status of a commercial Tempranillo vineyard was also evaluated using on-the-go thermal imagery retrieved from a moving quad at 5 km/h in Rioja. Moreover, an infrared radiometer was installed in an autonomous terrestrial robot to assess and map water status of commercial Touriga Nacional vineyard in the Douro Valley. 

Conclusions: 

Several trials carried out in Spain and Portugal showed the effectiveness of thermal imaging to monitor water status in commercial vineyards.

Significance and Impact of the Study: Our results are promising and show the potential of thermal imaging as a non-invasive technology in precision viticulture to evaluate vineyard water status, helping grape growers to optimize irrigation management.

DOI:

Publication date: March 23, 2021

Issue: Terroir 2020

Type: Video

Authors

Javier Tardaguila1*, Maria P. Diago1, Juan Fernández-Novales1, Inés Hernández1, Salvador Gutierrez2, Fernando Alves3, Joana Valente3, Ricardo Egipto4, Gonçalo Victorino5, J. Miguel Costa5, Carlos M. Lopes5

1Televitis Research Group. University of La Rioja. 26006 Logroño, Spain
2Department of Computer Science and Engineering, University of Cádiz, 11519 Puerto Real, Spain
3 Symington Family Estates, Travessa Barão de Forrester 86, 4431-901 Vila Nova de Gaia, Portugal
 4INIAV, I.P. Pólo de Dois Portos, Quinta da Almoínha. 2565-191, Dois Portos, Portugal
5LEAF, Instituto Superior de Agronomia. Universidade de Lisboa. 1349-017 Lisboa, Portugal

Contact the author

Keywords

Sensing technologies, non-invasive sensor, CWSI, IG, precision irrigation

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.