terclim by ICS banner
IVES 9 IVES Conference Series 9 An evaluation of the physiological responses of young grapevines planted and maintained under water constraint 

An evaluation of the physiological responses of young grapevines planted and maintained under water constraint 

Abstract

The aim of this ongoing study is to evaluate the degree of adaptability of grapevine scion:rootstock combinations to different conditions of water constraint. Here we present results from the young vine development phase, using three scenarios of water constraint that were implemented from planting. The experimental vineyard was established in 2020 and the data presented will cover the 2021/2022 and 2022/2023 seasons. The experiment consisted of the cultivars Pinotage (PIN), Shiraz (SHI) and Cabernet Sauvignon (CAB), grafted on two rootstocks, Richter 110 (R110) and USVIT-8-7 (US87). The different scion:rootstock combinations were planted and maintained under well-watered conditions, a 50% reduction of irrigation, as well as no irrigation (dryland). Morphological, phenological, physiological and carpological measurements were gathered in addition to soil moisture measurements and environmental monitoring. Results indicated a strong negative vegetative response to the increased water constraint, especially in vines grafted on R110.  Moreover, all of the different scion:rootstock combinations reduced stomatal conductance to conserve water use under reduced irrigation conditions. Phenological progression and ripening monitoring indicated that vines advanced their phenology when they experience recurring water constraint. A lowering in total vine yield was observed in the dryland vines, though the difference was not as pronounced in the CAB combinations. A high degree of phenotypic plasticity was observed in most plant-level measurements. The data will be discussed from the perspective of evaluating adaptability to the stressors and to draw attention to the importance of experiments where the responses to water constraint are followed from planting onwards.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Poster

Authors

Reinhard Swart1*, Anke Berry1, Stenford Matsikidze1, Philip Young1, Anscha Zietsman,Talitha Venter, Carlos Poblete-Echeverria1­­, Melané A. Vivier1

1 South African Grape and Wine Research Institute (SAGWRI), Faculty of AgriSciences, Stellenbosch University, Matieland 7602, South Africa

Contact the author*

Keywords

adaptation, viticulture, dryland, water stress, phenology

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Influence of must fining on wine pinking: relationship between electrochemical and colorimetric measurements and pinking attitude of wine

“Pinking” is a term used to define an abnormal pink coloration assumed by white wines in certain cases. Despite the are many hypotheses about the causes of this phenomenon, pinking still represents an issue for the wine industry. In the absence of reliable preventive strategies, wineries often rely on treatments such as charcoal fining, which is also negatively impacting wine aroma. This study aims at evaluating the potential of different fining agents based on animal or vegetal proteins to prevent wine pinking when applied at the level of must clarification. The work was carried out on Lugana wines, which is well-recognised as sensible to pinking problems. METHODS: Two experimental Lugana musts were obtained by applying a standard winemaking protocol and were then clarified with different commercial preparations based on vegetal proteins or casein, alone or in combination with PVPP. A control only using pectolytic enzyme was also prepared. Finings were carried out at 4°C for 16h, and the clear must (200 NTU) was then fermented in controlled conditions.

Aroma composition of young and aged Lugana and Verdicchio

AIM Verdicchio and Lugana are two Italian white wines produced in the Marche and Garda lake regions respectively. They are however obtained using grape varieties sharing the same genetic background, locally known as Verdicchio in Marche and Trebbiano di Soave in Garda. Anecdotal evidence suggests that these two wine types exhibit distinctive aroma features. The aim of this work was to explore the existence of a recognizable odour profile for Lugana and Verdicchio, and whether specific aroma chemical markers could be identified. METHODS 13 commercial wines, 6 Lugana and 7 Verdicchio were used. Sensory analysis was done using sorting task methodology, assessing only odor similarities. A total of 53 volatile compounds were identified and quantified GC-MS analysis. Aging behaviors were also evaluated after an accelerated aging at 40 ° C for 3 months. RESULTS HCA analysis of sorting task data identified indeed two groups: one characterized by floral and minty notes and mostly associated with Lugana wines, the other characterized by spicy and toasted aromas and mostly associated with Verdicchio. From a chemical point of view, major differences between the two wines types were observed for cis-3-hexenol, methionol, phenylethyl alcohol, and geraniol.

Variability of Tempranillo phenology within the toro do (Spain) and its relationship to climatic characteristics

Aims: The objective of this research was to analyse the spatial and temporal variability of vine phenology of the Tempranillo variety in the Toro Designation of Origen (DO) related to climatic conditions at present and under future climate change scenarios.

Impact of grape ripening and post-harvest withering on must composition and fermentation kinetics

Postharvest dehydration is a widely employed technique in winemaking to enhance sugar concentration and secondary metabolites from grapes. Different grape varieties exhibit varying responses in terms of dehydration rate and the resulting chemical composition.

Intra-block variations of vine water status in time and space

Vine water status was measured on 96 plots of three vines inside a vineyard block of 0.28 ha during three years: 2003, 2004 and 2005. Three physiological indicators were implemented: stem water potential, carbon isotope discrimination measured on grape sugars at ripeness (δ13C) and canopy temperature measured by high resolution remote sensing. For stem water potential, measurements were taken on every single vine of each plot.