terclim by ICS banner
IVES 9 IVES Conference Series 9 Postveraison shoot trimming in Tannat and Merlot: preliminary results on yield components, plant balance and berry composition

Postveraison shoot trimming in Tannat and Merlot: preliminary results on yield components, plant balance and berry composition

Abstract

There is currently a trend towards the production of wines with low alcohol content. To achieve this, grapes with low sugar content must be used. There are techniques at the vineyard level that can delay ripening and avoid excessive sugar accumulation without, a priori, affecting the final polyphenol content. Postveraison shoot trimming (PVST) is experimentally evaluated for these purposes, but its impact under Uruguayan climatic conditions with high interannual variability is not known. The aim of this work is to assess the PVST in Tannat and Merlot cultivars and their impact on yield components, plant balance and berry primary composition. In this study, two commercial vineyards of 10 years old Tannat and Merlot (grafted on SO4) at Canelones Department were selected. During the 2020-201 growing season, grapevines were submitted to PVST when grapes reached 15º Brix. In a randomized block, trimmed (T) and control (C) plants were evaluated with three repetitions each cultivar. Evaluation of the evolution of primary berry composition during ripening, measurement of yield components and plant balance were performed. For both cultivars, PVST did not affect yield components. Merlot reached 5.4 kg per plant and Tannat 7.1 kg, with not statistical significance between treatments. However, statistical differences were observed in terms of plant balance. In Merlot Ravaz Index reached a difference of 5.3 (12.0 in T and 6.7 in C) meanwhile Tannat reached 3.5 of statistical difference (13.7 in T and 10.2 in C). The tendency to imbalance for the treated plants had an impact on the final grape composition. Merlot grapes showed statistical difference in final total acidity (0.3 g of difference between treatments) while treatments impact final sugar content on Tannat grapes (10.0 g of difference between treatments). Further studies are needed to assess the impact of different canopy management techniques in our conditions.

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Poster

Authors

Mercedes Fourment, Agustina Clara, Valeria Cazzola, Julia Salvarrey and Diego Piccardo

Facultad de Agronomía, Universidad de la República Oriental del Uruguay, Montevideo, Uruguay

Contact the author

Keywords

Tannat, Merlot, canopy management, climate variability, Uruguay

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

Green Vineyards: skills development for wine industry personnel: responding to the challenges of climate change

A fair and sustainable society, with a modern, resource-efficient and competitive economy cannot be achieved without a workforce to support it.

Read More

Dual mode of action of grape cane extracts against Botrytis cinerea

Crude extracts of Vitis vinifera canes represent a natural source of stilbene compounds with well characterized antifungals properties. In our trials, exogenous application of a stilbene extract (SE) obtained from grape canes on grapevine leaves reduces the necrotic lesions caused by Botrytis cinerea

Read More

Chemical markers in wine related to low levels of yeast available nitrogen in the grape

Nitrogen is an important nutrient of yeast and its low content in grape must is a major cause for sluggish fermentations. To prevent problems during fermentation, a supplementation of the must with ammonium salts or more complex nitrogen mixtures is practiced in the cellar. However this correction seems to improve only partially the quality of wine [1]. In fact, yeast is using nitrogen in many of its metabolic pathways and depending of the sort of the nitrogen source (ammonium or amino acids) it produces different flavor active compounds. A limitation in amino acids can lead to a change in the metabolic pathways of yeast and consequently alter wine quality.

Read More

Pedoclimatic comparison of three viticultural areas of Italy devoted to high-quality Aglianico and Cabernet Sauvignon production

Aim: The study aims to show how different pedo-climatic conditions (past, present, and future) in three Italian sites at different latitudes (from center to southern), affect the adaptation of two red grapevine cultivars: Aglianico and Cabernet Sauvignon.

Read More

Effects of Silver Thiosulphate and Salicylic Acid on the long-term maintenance of the embryogenic callus of Vitis vinifera

New Plant Breeding Techniques (NPBTs) have the potential to revolutionize the genetic improvement of grapevine. However, the practical application of these techniques is limited by several challenges, such as the difficulty in generating embryogenic calluses, maintaining their competence during in vitro cultivation, and regenerating plants without defects. To overcome these challenges, we conducted a study to test the effect of two treatments on callus cultures derived from different grapevine varieties, with and without embryogenic competence. The tested substances were Silver Thiosulphate (STS) an ethylene inhibitor, and Salicylic Acid (SA), an elicitor with different effects depending on the concentration of use beyond the ethylene inhibitor activity.

Read More