Climatic influences on Mencía grapevine phenology and grape composition for Amandi (Ribeira Sacra, Spain)

Grape anthocyanin content and composition could affect the quality and the production strategies of red wines. Differences in the pigment composition modify the color properties in terms of hue, extractability and stability. Thus, for the production of a highly qualitative wine such as “Amarone”, variations in the pigment composition are not negligible. The aim of this work was the investigation of the anthocyanin profile changes during ripening in Corvina grapes, the main cultivar for the “Amarone” production. The experiment took place in 2015, in two vineyards located in Valpollicella (Italy).

Il Nebbiolo, uno dei vitigni più rappresentativi della viticoltura piemontese. é caratterizzato da una maturazione tardiva, una elevata vigoria e una bassa fertilità basale. La sua popolazione inoltre presenta una tale variabilità morfologica che é consuetudine suddividere il vitigno in diverse sottovarietà (Lampia, Rosé, Michet, Balla per citare solo quelle dell’areale albese) ognuna con presunte distinte caratteristiche morfologiche e produttive.

A study of the physiological and agronomical behaviour of the vine (cv. Chasselas) was conducted between 2001 and 2003 by the Swiss Federal Research Station for Plant Production at Changins (Agroscope RAC Changins) on various wine-growing farms (terroirs) in the Canton of Vaud (Switzerland), as part of a study project on Vaudois

AIM: Many research studies have analyzed the effect of polysaccharides in the aromatic composition of white wines.

The aim of this work was to analyze the variability in grape composition of the Tempranillo cultivar related to climatic conditions, in La Mancha Designation of Origin. Grape composition (sugar content, total acidity, pH, malic acid, and total and extractable anthocyanins) recorded during ripening, were analysed for the period 2000-2019. The weather conditions at daily time scale, recorded during the same period, were also evaluated. The relationships between grape parameters with climatic variables related to temperature and to water deficits, referring different periods between phenological events along the growing cycle, were evaluated using regression analysis. High variability in grape composition was observed in the period analysed. Total acidity varied between 3.7 and 7.3 gL-1 while malic acid varied between 1.2 and 4 gL-1. The extractable anthocyanins ranged between 526 and 972 mgL-1, and total anthocyanins ranged between 922 and 1388 mgL-1, being the lowest values recorded in the hottest year (2017). Total acidity decreased 0.77 gL-1 for an increase of 100 GDD, while malic acid decrease in 0.42 gL-1 for the same GDD increase, being the period between veraison and harvest the one that seemed to have higher influence on acidity. In addition, it was confirmed that increasing water deficits decreased acidity. Total and extractable anthocyanins increased in about 210 and 105 mgL-1, respectively, with an increase of 100 GDD from veraison to harvest, and the increase in water deficits favour the increase of anthocyanins, both total and extractable anthocyanins. Total and extractable anthocyanins concentration increased in 35 and 22 mgL-1 per an increase of 10 mm in the water deficit. These results can be of interest to understand the potential changes that grapes composition may suffer under future warmer climates.