GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 Characterisation of berry shrivel in Vitis vinifera L. Cultivars in the Stellenbosch wine region

Characterisation of berry shrivel in Vitis vinifera L. Cultivars in the Stellenbosch wine region

Abstract

Context and purpose of the study – Late season dehydration, bunch stem necrosis, sugar accumulation disorder and sunburn are various types of berry shrivel occurring in vineyards. The incidence of these types of shrivel, and the degree to which it occur are influenced by various factors in the vineyard. These factors include the presence of pests and diseases in the vineyard, genetic traits expressed in certain cultivars, as well as climatic and environmental factors. The occurrence of berry shrivel in the vineyard could negatively impact the quality and quantity of the fruit produced. The aim of this study was to visually characterise the different types of berry shrivel occurring and the corresponding in two cultivars Vitis vinifera L. Chenin blanc and Shiraz in the Stellenbosch Wine region.

Material and methods – In this study the occurrence of berry shrivel in Chenin blanc and Shiraz grapes were studied in two vineyards in the Stellenbosch Wine of Origin district during the 2017/2018 ripening season. Two distinct microclimates were established by implementing a leaf removal treatment in the bunch zone of the canopies on the morning side of some of the experimental panels around véraison, leading to a more exposed microclimate (leaf removal treatment) versus untreated control panels. To confirm microclimatic impacts, loggers were placed in the vineyards to measure the temperatures in the bunch zone of the control and treatment panels. Additionally, grape composition (berry fresh weight, berry volume, total soluble solids, pH and TA was monitored during the growing season for each of the grape cultivars.

Results – Bunches on vines where leaves were removed were exposed to more direct sunlight and temperature extremes, hence sunburn‐related berry shrivel was induced in these vines, especially in the Chenin blanc cultivar. Other types of berry shrivel were however also identified in both cultivars to various degrees during the ripening season, but late stage dehydration also occurred in both cultivars at the overripe stage. It was possible to visually follow the progress of shrivelling throughout the season and a grading scale was implemented to calculate the affected bunch areas. Slight differences were observed in the grape composition of the control (shaded) and exposed (treatment).

Download the PDF

DOI:

Publication date: September 27, 2023

Issue: GiESCO 2019

Type: Poster

Authors

Erna BLANCQUAERT1

1Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa

Contact the author

Keywords

berry shrivel, dehydration, necrosis, sunburn

Tags

GiESCO | GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Exogeneous C-S lyase enzyme, a potential tool for thiol enhancement in wine or beer?

Varietal thiols are considered for years as key aroma compounds in many wines. Their main origin is the cleavage during alcoholic fermentation of S-conjugate precursors present in grapes and musts, even if the levels of precursors already identified struggle to completely explain the levels of thiols found in wine.
Read More

The economic impact of drones on viticultural processes

Nowadays there are many challenges facing both winegrowers and workers, in other agricultural practices, related to the growing demand for food products, the safety and quality of these products, and the preservation of the environment…

Read More

Perception, liking and emotional response of tropical fruit aromas in Chardonnay wines

Tropical fruit aromas in wines are thought to be important to wine consumers, although there is little research to confirm this statement. With so many wine styles available, it has become important to understand the qualities that are desirable to consumers and how to achieve those qualities. Thiols and esters are compounds that have been found to cause tropical fruit aromas in chardonnay (ref). Fermentation temperature gradients and skin contact were found to increase these compounds using micro scale fermentations. This work aimed to scale up these fermentations/operations to determine if the desired tropical fruit aromas could still be achieved and if there is a perceivable difference in tropical fruit aromas, liking, and emotional response in the wines at the consumer level.

Read More

PROFILING OF LIPIDS IN WINES FROM MONOCULTURE FERMENTATION WITH INDIGENOUS METSCHNIKOWIA YEAST SPECIES

Lipids are a diverse group of organic compounds essential for living systems. They are vital compounds for yeast which makes them an important modulator of yeast metabolism in alcoholic fermentation. This study presents a comprehensive lipidome analysis of wine samples from the Vitis vinifera L., Maraština. The fermentation trails were set up in monoculture with different indigenous yeast strains selected from a collection of native yeasts established at the Institute for Adriatic Crops and Karst Reclamation in 2021, previously isolated from Croatian Maraština grapes: Metschnikowia pulcherrima, Metshnikowia sinensis/shanxiensis , and Metschnikowia chyrsoperlae.

Read More

Big data analysis of pesticides from the vine to the winery

Of biocontrol products and resistant grape varieties, synthetic pesticides are still widely used to control fungal diseases and protect vines from potential damage caused by pests. The use of pesticides is strictly regulated, and their use can sometimes lead to transfer from the grapes to the must and then into the wine. The study of pesticide residues in grapes and wines is commonly carried out by wine producers in order, among other things, to optimize treatment routes, check that products comply with regulations, and ultimately guarantee the food safety of the wine.

Read More