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…

Influence of irrigation frequency on berry phenolic composition of red grape varieties cultivated in four spanish wine-growing regions

The global warming phenomenon involves the frequency of extreme meteorological events accompanied by a change in rainfall distribution. Irrigation frequency (IF) affects the spatial and temporal soil water distribution but its effects on the phenolic composition of the grape have been scarcely studied. The aim of this work was to evaluate the effects of four deficit irrigation frequencies of 30 % ETo: one irrigation per day (T01), two irrigations per week (T03), one irrigation per week (T07) and one irrigation every two weeks (T15) on berry phenolic composition at harvest.

Characterization of a Sémillon clonal population: exploring genetic diversity, metabolomic profiles, and phenotypic variations

Sémillon is a cultivated grape variety known for contributing to dry and sweet white wine production. However, only seven approved clones have been officially recognized in France[1]. In this study, we aimed to characterize the genetic diversity and metabolomic profiles of a Sémillon clonal population, shedding light on the potential variations within this important grape variety.

Grapevine adaptation to drought and resistance to Neofusicoccum parvum, causal agent of Botryosphaeria dieback

The sustainability of viticulture in response to climate change has been addressed mainly considering agronomic impacts, such as water management and diseases, either separately or together.
In grapevines, there is strong evidence that different genotypes respond differently to biotic and abiotic stresses. A screening was conducted on various local cultivars in response to drought and Neofusicoum parvum infection aiming to evaluate their susceptibility to abiotic stress and resistance to fungal diseases.

Accumulation of deleterious mutations in grapevine and its relationship with traits of interest for wine production and resilience

Deleterious mutations that severely reduce population fitness are rapidly removed from the gene pool by purifying selection. However, evolutionary drivers such as genetic drift brought about by demographic bottlenecks may comprise its efficacy by allowing deleterious mutations to accumulate, thereby limiting the adaptive potential of populations. Moreover, positive selection can hitchhike mildly deleterious mutations due to linkage caused by lack of recombination. Similarly, in the context of species domestication, artificial selection mimics these evolutionary processes, which can have undesirable consequences for production and resilience. In this study, we evaluated the extent of the accumulation of deleterious mutations and the magnitude of their effects (also known as genetic load) at the whole-genome scale for ca.

Physicochemical behaviour of wine spirit and wine distillate aged in Sherry Casks® and Brandy casks

Brandy is a spirit drink made from “wine spirit” (<86% Alcohol by Volume – ABV; high levels of congeners and they are mainly less volatile than ethanol), it may be blended with a “wine distillate” (<94.8%ABV; low levels of congeners and these are mainly more volatile than ethanol), as long as that distillate does not exceed a maximum of 50% of the alcoholic content of the finished product[1]. Brandy must be aged for at least 6 months in oak casks with <1000L of capacity. During ageing, changes occur in colour, flavour, and aroma that improve the quality of the original distillate.