terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Late winter pruning induces a maturity delay under temperature-increased conditions in cv. Merlot from Chile

Late winter pruning induces a maturity delay under temperature-increased conditions in cv. Merlot from Chile

Abstract

Chile is considered vulnerable to climate change; and these phenomena affect several mechanisms in the grape physiology and quality. The global temperature increase affects sugar contents, organic acids, and phenolic compounds in grapes, producing an imbalance maturity. In this sense, an alternative to reduce the impact is to perform pruning after vine budburst, known as “Late Pruning” (LP).

The study aims are evaluating the LP, under ambient (Control) and temperature increase (T+) conditions, as agronomical technique that allows the imbalance of sugar and anthocyanins and delaying grapes maturation in cv. Merlot (Valle central, Chile) during two seasons. To achieve this goal tree pruning were made: winter pruning (WP); LP1 (Late pruning at budbreak) and LP2 (at shoots of 2-4 cm). The phenology of the crop was monitored and gas exchange, chlorophyll fluorescence and photosynthetic pigments were determined at key growth stages. At harvest (22±1 ºBrix), anthocyanins and total soluble solids were determined to evaluate the development of maturation.

During two seasons (21-22; 22-23) temperatures produced an earlier harvest in WP. LP1 treatments under control conditions had no effect on harvest date, and LP2 even advanced it. Under T+ conditions, LP1 had the most positive effects, delaying harvest by 5 to 22 days (season depending) and increasing total anthocyanin by 12% under ambient conditions and by 19% at T+. Regarding the effects on gas exchange, temperature significantly reduced photosynthesis in both seasons, but LP had no effect. In conclusion, the delay of sugar accumulation due to LP at budbreak could have a positive effect on anthocyanin concentration, without affecting other parameters such as photosynthesis.

Acknowledgements: This study is part of the project Fondecyt 11200703 (ANID). Thanks to Manuel Gutierrez for his field work and Jose Macias, graduate student.

DOI:

Publication date: October 25, 2023

Issue: ICGWS 2023

Type: Article

Authors

C. Salazar-Parra1*, R. Rivera1,2, M. Miranda1, M. Reyes3, C. Peppi1

1Instituto de investigaciones agropecuarias, INIA La Platina.
2Undergraduate student. Facultad de Ciencias. Universidad de Chile.
3Instituto de investigaciones agropecuarias. INIA Raihuen.

Contact the author*

Keywords

temperature, anthocyanins, grapevine, climate change, sugars

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Aromatic characterization of Moscato Giallo by GC-MS/MS and stable isotopic ratio analysis of the major volatile compounds

Among the Moscato grapes, Moscato Giallo is a winegrape variety characterized by a high content of free and glycosylated monoterpenoids, which gives very aromatic wines. The aromatic bouquet of Moscato Giallo is strongly influenced by the high concentration of linalool, geraniol, linalool oxides, limonene, α-terpineol, citronellol, HO-trienol, HO-diols, 8-Hydroxylinalool, geranic acid and β-myrcene, that give citrus, rose, and peach notes.

The evolution of the aromatic composition of carbonic maceration wines

The vinification by Carbonic maceration (CM) involves the process whereby the whole bunches are subjected to anaerobic conditions during several days. In this anaerobic condition, the grape endogenous enzymes begin an intracellular fermentation. This situation favors that whole grapes split open and release their juice into the tank, increasing the liquid phase that is fermented by yeasts [1]. Then, two types of wines are obtained; one from the free-run liquid in the tank (FCM) and other from the liquid after pressing the whole grape bunches (PCM). PCM wines are recognized as high quality young wines because their fruity and floral aromas[2] that although they are very intense at the end of the winemaking they gradually disappear during conservation.

REGAVID a decision tool to deficit irrigation in a temperate climate (DO Monterrei – Spain)

In temperate climates, such as in the North of Spain, the use of irrigation in the vineyard has not been required, due to the usual rainfall from June to August. In some large vineyards, irrigation management has been carried out, based on occasional support irrigation, or for the application of nutrients (fertigation). Currently it is necessary to implement decision support models to manage irrigation water in real time and avoid misuse of a scarce resource. Moreover, quality standards must be achieved, as in the previous rainfed viticulture.

Effect of ultraviolet B radiation on pathogenic molds of grapes

The fungicidal effect of UV-C radiation (100-280 nm wavelength) is well known, but its applicability for the control of pathogenic molds of grapes is conditioned by its effect on the host and by the risks inherent in its handling[1].
As an alternative, the effect in vitro of UV-B radiation (280-315 nm) on the main pathogenic molds of grapes has been studied: Botrytis cinerea, Aspergillus niger, Penicillium expansum and Rhizopus stolonifer.

Polyphenol content of cork granulates at different steps of the manufacturing process of microagglomerated stoppers treated with supercritical CO2 used for wine bottling

The wine closure industry is mainly divided into three categories: screw caps, synthetic closures, and cork-based closures. Among this latter, microagglomerated cork stoppers treated with supercritical CO2 are now widely used, especially to avoid cork taint contaminations[1]. They are designed with cork granules obtained from cork offcuts of the punching process during the natural cork stoppers production. A previous study[2] showed that these stoppers released fewer polyphenols in 12 % (v/v) hydroalcoholic solution than natural cork stoppers.