Terroir 2020 banner
IVES 9 IVES Conference Series 9 Agronomic and qualitative effects of early leaf removal on cv.

Agronomic and qualitative effects of early leaf removal on cv.

Abstract

Aim: The regulation of the vegetative-reproductive balance of a vineyard is a critical aspect for the quality of grapes. Early leaf removal, generally applied before the phenological stage of flowering, is mainly used as a technique to control yield and improve grape health, aimed at increasing the quality of the wine. The vineyard’s response to early leaf removal may depend on the variety, climate, and growing conditions. The aim of this study is to assess the impacts of early leaf removal on the optimisation of the grape ripening process.

Methods and Results: In the D.O. Rueda, Spain, throughout the period of 2015-2018, the application of basal leaf removal was applied at the beginning of flowering.  The first eight adult leaves were removed from the base of all the shoots and vine performance assessed. The trial was carried out in a rain fed vineyard of Verdejo, grafted to 110R, planted in 2006, with 2.60 x 1.25 m row and vine spacing, and trained on to a vertical trellis. 

Early leaf removal reduced yield by 15%, through a reduction in the bunch weight, affected by a reduction in the number of berries. The weight of the berry and the number of clusters per vine were not affected by early leaf removal. The vegetative development was affected by leaf removal, slightly reducing the leaf area and the pruning weight, in line with the weight of the shoot, also reducing the Ravaz index.

The concentration of sugars increased slightly due to early leaf removal. The pH of must was slightly lower, while the titratable acidity and the tartaric acid increased slightly with the application of leaf removal. The malic acid decreased and the potassium increased slightly due to early leaf removal.

Conclusions:

Early leaf removal can be applied to control yield and to favour the maturation and the quality of Verdejo grapes grown under rainfed conditions. However, its application must be considered according to the climatic situation and the type of wine that is intended to be produced.

Significance and Impact of the Study: A benefit of early leaf removal is a reduction in cluster compactness and cluster weight which can improve the grape quality in the cv. Verdejo under rainfed conditions, taking into account the desired grape characteristics.

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type : Video

Authors

Jesus Yuste* and Daniel Martinez-Porro

Instituto Tecnologico Agrario de Castilla y Leon, Ctra. Burgos km 119, 47071 Valladolid, Spain

Contact the author

Keywords

Acidity, grapevine, ripening, sugars, yield

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Evolution of flavonols during Merlot winemaking processes

The phenomenon of quercetin precipitation in wine (flanovol haze), has been manifested for many years in several wine-producing regions

Fining-Derived Allergens in Wine: from Detection to Quantification

Since 2012, EU Commission approved compulsory labeling of wines treated with allergenic additives or processing aids “if their presence can be detected in the final product” (EU Commission Implementing Regulation No. 579/2012 of 29 June 2012). The list of potential allergens to be indicated on wine labels comprises sulphur dioxide and milk- and egg- derived fining agents, including hen egg lysozyme, which is usually added in wines as preservative. In some non-EU countries, the list includes gluten, tree nuts and fish gelatins. With the exception of lysozyme, all these fining proteins were long thought to be totally removed by subsequent winemaking processings (e.g. bentonite addition).

Territoire, terroir et marché du vin à la production

Work aimed at understanding the relationship between a terroir, in the agronomic sense, and the physico-chemical characteristics of grapes or wine are numerous today, as evidenced by the program of this symposium. But for an economist, the central question remains to know how the terroir can intervene in the construction of the economic value of wine and in the differentiation of its prices. Is the terroir effect recognized by the end consumer or is it only an internal adjustment variable in the production systems? Through which indicators can this terroir effect be managed by the various operators in the sector? In the end, isn’t it better to invoke a “territorial effect” that the actors can build, and of which the terroir would be one of the possible components?

Differentiation and characterization of Spanish fortified wines with protected designation of origin based on volatiles using multivariate approaches

Spain is one of the main producers of high-quality fortified wines. Particularly some of them elaborated in Andalusia have acquired a great prestige for being unique due to their production in a specific geographical area with traditional methods, the grape variety used, the climate and the soil. Such is their distinguishing feature achieved that they have been protected by the European Union with the indication “Protected Designation of Origin” (PDO). Thus, there are four PDO of fortified wines in Andalucía (‘Condado de Huelva’, ‘Jerez Xérès Sherry’, ‘Manzanilla Sanlúcar de Barrameda’, and ‘Montilla-Moriles’). Furthermore, within each PDO,there are different categories according to their particular characteristics and winemaking conditions such as the aging process.

Evaluating South African Chenin blanc wine styles using an LC-MS screening method

Sorting Chenin blanc is one of the most important white wine cultivars in South Africa. It has received a lot of attention and accolades in the past years and more research than ever is dedicated to this versatile cultivar. According to the Chenin blanc association of South Africa, there are three recognized dry wine styles, Fresh and Fruity (FF), Rich and Ripe Unwooded
(RRU), and Rich and Ripe Wooded (RRW). They are traditionally established with the aid of expert sensory evaluation, but the cost and the (subjective) human factor are aspects to be taken into account. A more objective and possibly robust way of assessing and attributing these styles can be the use of chemical analysis.