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).

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…

Co-design and evaluation of spatially explicit strategies of adaptation to climate change in a Mediterranean watershed

Climate change challenges differently wine growing systems, depending on their biophysical, sociological and economic features. Therefore, there is a need to locally design and evaluate adaptation strategies combining several technical options, and considering the local opportunities and constraints (e.g. water access, wine typicity). The case study took place in a typical and heterogeneous Mediterranean vineyard of 1,500 ha in the South of France. We developed a participatory modeling approach to (1) conceptualize local climate change issues and design spatially explicit adaptation strategies with stakeholders, (2) numerically evaluate their effects on phenology, yield and irrigation needs under the high-emissions climate change scenario RCP 8.5, and (3) collectively discuss simulation results. We organized five sets of workshops, with in-between modeling phases. A process-based model was developed that allowed to evaluate the effects of six technical options (late varieties, irrigation, water saving by reducing canopy size, adjusting cover cropping, reducing density, and shading) with various distributions in the watershed, as well as vineyard relocation. Overall, we co-designed three adaptation strategies. Delay harvest strategy with late varieties showed little effects on decreasing air temperature during ripening. Water constraint limitation strategy would compensate for production losses if disruptive adaptations (e.g. reduced density) were adopted, and more land got access to irrigation. Relocation strategy would foster high premium wine production in the constrained mountainous areas where grapevine is less impacted by climate change. This research shows that a spatial distribution of technical changes gives room for adaptation to climate change, and that the collaboration with local stakeholders is a key to the identification of relevant adaptation. Further research should explore the potential of adaptation strategies based on soil quality improvement and on water stress tolerant varieties.

Short-term relationships between climate and grapevine trunk diseases in southern French vineyards

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Mesoclimate impact on Tannat in the Atlantic terroir of Uruguay

The study of climate is relevant as an element conditioning the typicity of a product, its quality and sustainability over the years. The grapevine development and growth and the final grape and wine composition are closely related to temperature, while climate components vary at mesoscale according to topography and/or proximity to large bodies of water. The objective of this work is to assess the mesoclimate of the Atlantic region of Uruguay and to determine the effect of topography and the ocean on temperature and consequently on Tannat grapevine behavior.

δ13C : A still underused indicator in precision viticulture  

The first demonstration of the interest of carbon isotope composition of sugars in grapevine, as an integrated indicator of vineyard water status, dates back to 2000 (Gaudillère et al., 1999; Van Leeuwen et al., 2001). Thanks to the isotopic discrimination of Carbon that takes place during plant photosynthesis, under hydric stress conditions, it is possible to accurately estimate the photosynthetic activity. Ever since, δ13C has been widely applied with success to zonation, terroir studies and vine physiology research, but is still not widely used by viticulturists. This is quite astonishing by considering the impact of global warming on viticulture and the need to improve water management, that would justify a widespread use of δ13C.
The lack of private laboratories proposing the analysis, the cost of the technology, as well as the long analytical delays, have been detrimental to its development. Some laboratories tried to overcome the analytical difficulties of isotopic analysis by using fourier transformed infrared spectroscopy, as a fast and cheap alternative to the official OIV method (IRMS). These claimed FTIR models have never been published or peer reviewed and cannot be considered robust. In this work, thanks to the recent acquisition of IRMS technology, new modern and robust applications of δ13C for viticulture are proposed. This includes the use of the analysis to make parcel separations at harvesting, the possibility to increase the precision of hydric stress cartography and the potential cost reduction when compared with Scholander pressure bomb analysis.

Bioclimatic shifts and land use options for Viticulture in Portugal

Land use, plays a relevant role in the climatic system. It endows means for agriculture practices thus contributing to the food supply. Since climate and land are closely intertwined through multiple interface processes, climate change may lead to significant impacts in land use. In this study, 1-km observational gridded datasets are used to assess changes in the Köppen–Geiger and Worldwide Bioclimatic (WBCS)