Terroir 2020 banner
IVES 9 IVES Conference Series 9 Leaf removal to regulate fruit ripening in Cabernet-Sauvignon

Leaf removal to regulate fruit ripening in Cabernet-Sauvignon

Abstract

Aim: Under the effects of climate change it is becoming increasingly common to observe excessively fast sugar accumulation while anthocyanin and flavour development are lagging behind. Understanding the impact of different leaf removal techniques on ripening will provide vineyard managers with a canopy management strategy suitable for regulating sugar accumulation, phenolic maturity and flavour ripeness, thereby helping to mitigate these negative effects. The aim of this research was to quantify the impacts of three different leaf removal techniques on the canopy architecture and ripening of Cabernet Sauvignon.

Methods and Results: Treatments were performed at veraison (~14 °Brix) and included: i) Control, ii) Leaf plucking around the bunches iii) Leaf plucking the top two thirds of shoots apical to the bunches, and iv) Shoot trimming. On the date of harvest no significant difference in grape TSS was observed between treatments. Other results including the effect of the treatments on acidity, anthocyanins, phenolics, and tannins were somewhat inconclusive.

Conclusions:

While various other studies have shown the potential to achieve slower grape sugar accumulation without affecting the concentration of anthocyanins, phenolics, and tannins, the results of this study do not indicate a decrease in the rate of grape sugar accumulation as a result of the investigated defoliation techniques.

Significance and Impact of the Study: Given the cost of implementing these treatments the results of this study do not support the use of these methods for the purpose of delaying fruit ripening in a hot Australian climate.

Download the PDF

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type : Video

Authors

Patrick O’Brien1, Cassandra Collins1,2, Roberta De Bei1*

1The University of Adelaide, School of Agriculture, Food and Wine, Waite Research Institute, PMB 1 Glen Osmond, 5064, South Australia, Australia.
2ARC Industrial Transformation Training Centre for Innovative Wine Production, Waite Research Institute, PMB 1 Glen Osmond, 5064, South Australia, Australia

Contact the author

Keywords

Delayed ripening, leaf removal, shoot trimming, canopy management, Cabernet-Sauvignon

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

The adaptative capacity of a viticultural area (Valle Telesina, Southern Italy) to climate changes

The viticulture aiming at the production of high quality wine is very important for the landscape conservation, because it allows to combine high farmer income with soil conservation

Read More

MODULATION OF YEAST-DERIVED AROMA COMPOUNDS IN CHARDONNAY WINES USING ENCAPSULATED DIAMMONIUM PHOSPHATE TO CONTROL NUTRIENT RELEASE

Yeast-derived aroma compounds are the result of different and complex biochemical pathways that mainly occur during alcoholic fermentation. Many of them are related -but not limited- to the availability of nutrients in the fermentation medium and linked to nitrogen metabolism and biomass produced. Besides, the metabolic phase of yeast also regulates the expression of many enzymes involved in the formation of aroma active compounds. The work investigates the overall effect of continuous supplementation of nutrients during alcoholic fermentation of a grape must on the volatile composition of wines.

Read More

NADES extraction of anthocyanins derivatives from grape pomace

Grape pomace is one of the main by-products generated after pressing in wine-making. It’s valorization through the extraction of bioactive compounds is the answer for the development of sustainable processes. Nevertheless, in the recovery of anthocyanins derivatives, the extraction stage continues to be a limiting step. The nature of the sample and the type of solvent determine the efficiency of the process

Read More

Timing of leaf removal effects on vitis vinifera L. Cv. Grenache differed on two contrasting seasons

Warming trends over the winegrowing regions lead to an advance of grapevine phenology, diminution of yield and increased sugar content and must pH with a lower polyphenol content, especially anthocyanins. Canopy management practices are applied to control the source sink balance and improve the cluster microclimate to enhance berry composition. We hyphothesized that an early leaf removal might promote a delayed ripening through severe defoliation after fruitset; whereas, a late leaf removal at mid-ripening would reduce sugar accumulation.

Read More

Terroir Hesse – Soil determines wine style

The project “Terroir Hesse” works out the main type and characteristics of soil-based terroirs and the resulting wine styles for the hessian wine-growing regions Rheingau and Hessian Bergstrasse.

Read More