GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 Berry weight loss in Vitis vinifera (L.) cultivars during ripening

Berry weight loss in Vitis vinifera (L.) cultivars during ripening

Abstract

Abstract: Context and purpose of the study – Berry shriveling (BS) in vineyards are caused by numerous factors such as sunburn, dehydration, stem necrosis. Climate change results in an increase in day and night temperatures, rainfall throughout the year, changes in the timing and quantities, long dry summers and a combination of climatic variability such as floods, droughts and heatwaves). Grape development and its composition at harvest is influenced by the latter as grape metabolites are sensitive to the environmental conditions. The grape berry experiences water loss and an increase in flavour development as a result of the BS. An increased sugar content in grapes will result in higher alcohol wines and concentration of grape aromas which may be detrimental to the final wine quality. More so, crop estimations are negatively impacted as a result of BS which results in lower compensation for grape producers. This pilot study seeked to investigate the berry weight loss in twelve Vitis vinifera (L.) cultivars in WashingtonState.

Material and methods – This study was conducted during the 2018 growing seasons at the Washington State University (WSU) Irrigated Agriculture Research and Extension Center (IAREC) in Prosser, Washington, USA (46°17’N; 119°44’W; 365 m a.s.l.). The vineyard contained 30 wine grape cultivars (Vitis vinifera) separated into 16 main blocks of 13 row seach along with border sections of 5 vines each. All vines were planted at a spacing of m × 2.7 m (2058 vines/hectare). Grape cultivars were separated into groups of either white or red, with all vines planted in a north-south orientation using the Vertical Shoot Positioned (VSP) training system.Each of the 16 main blocks was dedicated too neoffour main cultivars;Merlot,CabernetSauvignon,Chardonnay, orRiesling. Border sections containing the additional 26 cultivars were located on the southern, eastern, and western portionsofthevineyard.Eachborder cultivar sectionconsistedofthreeorfourrepetitionsoffivevineseach.All weather data was gathered from the Roza automated weather station and the WSU AgWeatherNet system (AgWeatherNet2018).Berry fresh weight and total soluble solids were determined just after véraison throughout berry development.

Results – In this study on weight loss in ripening white (Chardonnay, Weisser Riesling, Gewurztraminer, Alvarinho, Muscat blanc and Sémillon) and red grape cultivars (Cabernet Sauvignon, Merlot noir, Grenache, Lemberger, Malbec, Cabernet franc) ripening curves of non-solutes per berry (mostly water) were similar to the berry weight curves. Solutes per berry (mostly sugar) increased to a maximum berry weight for most of the cultivars. Prior to véraison phloem sap is the only source for water and solutes that enter grape berries until maximum berry weight followed by a decrease in the solutes per berry. Later during the ripening stage berry shrinking occurred due to elevated transpiration, which resulted in an increase in ˚Brix (solutes). Grape cultivar, environmental and cultivation practices have an impact on the concentration of berry of solutes, which dictates the composition and will have an impact on the wine quality. However, this study needs to be repeated and the wine quality should be assessed.

DOI:

Publication date: September 18, 2023

Issue: GiESCO 2019

Type: Poster

Authors

Erna BLANQUAERT1*, Markus KELLER2

1 Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, Matieland7602, South Africa
2 Irrigated Agricultural Research and Extension Center, Washington State University, 24106 N. Bunn Road, Prosser, WA99350

Contact the author

Keywords

grape berry, berry weight, berry shrinkage

Tags

GiESCO | GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Terroir analysis and its complexity

Terroir is not only a geographical site, but it is a more complex concept able to express the “collective knowledge of the interactions” between the environment and the vines mediated through human action and “providing distinctive characteristics” to the final product (OIV 2010). It is often treated and accepted as a “black box”, in which the relationships between wine and its origin have not been clearly explained. Nevertheless, it is well known that terroir expression is strongly dependent on the physical environment, and in particular on the interaction between soil-plant and atmosphere system, which influences the grapevine responses, grapes composition and wine quality. The Terroir studying and mapping are based on viticultural zoning procedures, obtained with different levels of know-how, at different spatial and temporal scales, empiricism and complexity in the description of involved bio-physical processes, and integrating or not the multidisciplinary nature of the terroir. The scientific understanding of the mechanisms ruling both the vineyard variability and the quality of grapes is one of the most important scientific focuses of terroir research. In fact, this know-how is crucial for supporting the analysis of climate change impacts on terroir resilience, identifying new promised lands for viticulture, and driving vineyard management toward a target oenological goal. In this contribution, an overview of the last findings in terroir studies and approaches will be shown with special attention to the terroir resilience analysis to climate change, facing the use and abuse of terroir concept and new technology able to support it and identifying the terroir zones.

Spatial determination of areas in the Western Balkans region favorable for organic production

In problematic conditions for production of grapes and wine caused by the COVID-19 pandemic and the resulting occurrence of wine surpluses, producers are increasingly turning to the innovative viticulture and winemaking of products that are more appealing to the market and the consumers. On the other hand, consumption of the food safety or organic products, and therefore of organic grapes and wine, is increasingly common in the world, in particular in Europe. The Regional Rural Development Standing Working Group (SWG RRD), as a regional intergovernmental organization gathers actors in the viticulture and winemaking sector from states and territories of the Western Balkans (South-East Europe) in the Expert Working Group for Wine, with the aim of improving viticulture and winemaking in this region through joint activities. In accordance with the aforementioned, the SWG RRD is working on advancing organic production of grapes and wine, and on recognition of specificities of the terroir of wine-growing areas in Western Balkans. In addition, as part of the project “Facilitation of Exchange and Advice on Wine Regulations in Western Balkan Countries” helmed by the German Federal Ministry of Food and Agriculture, in addition to harmonization of relevant legislation with EU regulations, efforts are being invested towards recognition of organic wines. Within activities and project implemented by this organization, expert analyses and scientific research of the terroir of Western Balkans were carried out, and some of the results are presented in this paper.

Mechanisms involved in the heating of the environment by the aerodynamic action of a wind machine to protect a vineyard against spring frost

One of the main consequences of global warming is the rise of the mean temperature. Thus, the heat summation by the plants begins sooner in the early spring, and by cumulating growing degree-days, phenological development tends to happen earlier. However, spring frost is still a recurrent phenomenon causing serious damages to buds and therefore, threatening the harvests of the winegrowers. The wind machine is a solution to protect fruit crops against spring frost that is increasingly used. It is composed of a 10-m mast with a blowing fan at its peak. By tapping into the strength of the nocturnal thermal inversion, it sweeps the crop by propelling warm air above to the ground. Thus, stratification is momentarily suppressed. Furthermore, the continuous action of the machine, alone or in synergy, or the addition of a heater allow the bud to be bathed in a warmer environment. Also, the punctual action of the tower’s warm gust reaches the bud directly at each rotation period. All these actions allow the bud to continuously warm up, but with different intensities and over a different period. Although there is evidence of the effectiveness of the wind machines, the thermal transfers involved in those mechanisms raise questions about their true nature. Field measurements based on ultrasonic anemometers and fast responding thermocouples complemented by laboratory measurements on a reduced scale model allow to characterize both the airflow produced by the wind machine and the local temperature in its vicinity. Those experiments were realized in the vineyard of Quincy, in the framework of the SICTAG project. In the future paper, we will detail the aeraulic characterization of the wind machine and the thermal effects resulting from it and we will focus on how the wind machine warms up the local atmosphere and enables to reduce the freezing risk.

Influence of weather and climatic conditions on the viticultural production in Croatia

The research includes an analysis of the impact of weather conditions on phenological development of the vine and grape quality, through monitoring of four experimental cultivars (Chardonnay, Graševina, Merlot and Plavac mali) over two production years. In each experimental vineyard, which were evenly distributed throughout the regions of Slavonia and The Croatian Danube, Croatian Uplands,

The impact of sustainable management regimes on amino acid profiles in grape juice, grape skin flavonoids, and hydroxycinnamic acids

One of the biggest challenges of agriculture today is maintaining food safety and food quality while providing ecosystem services such as biodiversity conservation, pest and disease control, ensuring water quality and supply, and climate regulation. Organic farming was shown to promote biodiversity and carbon sequestration, and is therefore seen as one possibility of environmentally friendly production. Consumers expect organically grown crops to be free from chemical pesticides and mineral fertilizers and often presume that the quality of organically grown crops is different or higher compared to conventionally grown crops. Integrated, organic, and biodynamic viticulture were compared in a replicated field trial in Geisenheim, Germany (Vitis vinifera L. cv. Riesling). Amino acid profiles in juice, grape skin flavonoids, and hydroxycinnamic acids were monitored over three consecutive seasons beginning 7 years after conversion to organic and biodynamic viticulture, respectively. In addition, parameters such as soil nutrient status, yield, vigor, canopy temperature, and water stress were monitored to draw conclusions on reasons for the observed changes. Results revealed that the different sustainable management regimes highly differed in their amino acid profiles in juice and also in their skin flavonol content, whereas differences in the flavanol and hydroxycinnamic acid content were less pronounced. It is very likely that differences in nutrient status and yield determined amino acid profiles in juice, although all three systems showed similar amounts of mineralized nitrogen in the soil. Canopy structure and temperature in the bunch zone did not differ among treatments and therefore cannot account for the observed differences in favonols. A different light exposure of the bunches in the respective systems due to differences in vigor together with differences in berry size and a different water status of the vines might rather be responsible for the increase in flavonol content under organic and biodynamic viticulture.