terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Vineyard yield estimation using image analysis: assessing bunch occlusions and its dependency on fruiting zone canopy features

Vineyard yield estimation using image analysis: assessing bunch occlusions and its dependency on fruiting zone canopy features

Abstract

Performing accurate vineyard yield estimation is of upmost importance as it provides important benefits to the whole vine and wine industry. Recently, image-analysis approaches have been explored to address this issue however this approach has as main challenge the bunch occlusion, mostly by vegetation but also by neighboring bunches. The present work aims at assessing the magnitude of bunch occlusion by neighboring bunches and to evaluate its dependency on a selection of vegetative and reproductive vine parameters assessed at fruiting zone. Forty vine segments (1 m) of two vineyard plots of the white cultivars ‘Alvarinho’ and ‘Arinto’ were assessed for vegetative and reproductive features at fruiting zone and imaged with a 2D camera. Bunch occlusion by leaves presented the highest occlusion rates, reaching an average of 68.5% for both varieties. Bunch occlusion by neighboring bunches presented average values of 12.2 and 15.2%, respectively for ‘Alvarinho’ and ‘Arinto’. Regarding the correlations between the rate of bunch-by-bunch occlusion and the assessed vegetative and reproductive variables, all correlation coefficients were non-significant, indicating that this type of occlusion is not driven by one single variable but, instead, by an interplay of factors that integrates the effects of several vegetative and reproductive canopy features. The magnitude of bunch-by-bunch occlusion also shows that this type of occlusion shouldn´t be neglected as it can induce an underestimation of the yield, mainly when the image-analysis algorithms are based on the relationships between visible bunch area and bunch mass.

DOI:

Publication date: October 9, 2023

Issue: ICGWS 2023

Type: Poster

Authors

Gonçalo VICTORINO*, Enrico BISON, Jian CAO,  Carlos M. LOPES

LEAF—Linking Landscape, Environment, Agriculture and Food Research Center, Associated Laboratory TERRA, Instituto Superior de Agronomia, Universidade de Lisboa, Tapada da Ajuda, 1349-017 Lisboa, Portugal

Contact the author*

Keywords

Grapevine yield prediction; proximal sensing; bunch-by-bunch occlusion; Vitis vinifera L.

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Exploring the prevalence of esca-induced leaf symptoms in French vineyards and the role of climate: a national scale analysis

Esca, a severe trunk disease affecting vineyards, is caused by fungal pathogens that induce wood necrosis and decay, leaf symptoms, yield losses, and potentially a rapid death of the vine. The prevalence of this disease varies across years, regions, cultivars, and plot ages. Despite its significance in understanding and predicting dieback risk in different vineyards, the role of climate in trunk diseases remains a relatively unexplored research area. While some studies have demonstrated the impact of certain climatic conditions on the prevalence of the disease, they often focus on a limited number of plots and yield conflicting results.We conducted a statistical analysis, using a Bayesian approach on a national database comprising prevalence data of esca from over 500 different plots in France, spanning the years 2003 to 2022 and encompassing various cultivars.

Culturable microbial communities associated with the grapevine soil in vineyards of La Rioja, Spain

The definition of soil health is complex due to the lack of agreement on adequate indicators and to the high variability of global soils. Nevertheless, it has been widely used as synonymous of soil quality for more than one decade, and there is a consensus warning of scientists that soil quality and biodiversity loss are occurring due to the traditional intensive agricultural practices.
In this work we monitored a set of soil parameters, both physicochemical and microbiological, in an experimental vineyard under three different management and land use systems: a) addition of external organic matter (EOM) to tilled soil; b) no tillage and plant cover between grapevine rows, and c) grapevines planted in rows running down the slope and tilled soil.

Addition of glutathione-rich inactivated yeasts to white musts: effects on wine composition and sensory quality

Glutathione plays a key role in preventing some oxidative processes during winemaking. This molecule limits the must enzymatic oxidation, reacts with caffeic acid and generates a colourless compound that prevents subsequent browning. It also has a protective effect on wine aroma, preventing the oxidation of the volatile compounds with a high sensory impact.

Decoupling the effects of water and heat stress on Sauvignon blanc berries

Climate changes have important consequences in viticulture, heat waves accompanied by periods of drought are encountered more and more frequently. This study aims to evaluate the single and combined effect of water deficit and high temperatures on the thiol precursors biosynthesis in Sauvignon blanc grapes. For this purpose, a protocol has been developed for the cultivation of berries on a solid substrate. The berries, collected at three different times starting from veraison and grown in vitro, were subjected to 4 different treatments: control (C), water stress (WS), heat stress (HS), combined water and heat stress (WSHS). Water stress was simulated by adding abscisic acid to the culture medium, while different temperatures, respectively 25°C and 35°C, were managed with two illuminated climatic chambers.

Quantification of polysaccharides of variety Pomaces of the D.O.Ca Rioja

Pomace is one of the main residues generated by the wine industry and represents an environmental problem. Currently, there is a growing interest in the revaluation of these products because different bioactive compounds can be obtained from them, such as polyphenols, grape seed oils and polysaccharides. Red grape pomace can be an important source of polysaccharides, but they are currently little studied and even less with viable and environmental extraction processes (green extraction), such as flash extraction. The residual amount of the fraction rich in pectin (residual pulp) and component rich in hemicellulose in the pomace and the strength of association of the pectin with the cellulose-xyloglucan network depend on the degree of extractability of the polysaccharides in red winemaking and on the winemaking conditions.