Impact of deficit irrigation strategies on terpene concentration in Gewürztraminer grapes

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.

The global consumer demand for low or non-alcoholic wine is growing steadily in recent years, driven by health concerns, religious beliefs, and personal taste preferences etc.. Consequently, the removal of alcohol from wine can significantly alter its chemical and sensory properties, including color, aroma, and taste, which make a significant challenge for consumer to accept these products. Ethanol plays a crucial role in various chemical reactions and interactions that contribute to the development of wine’s characteristics.

Regionality, frequently called terroir, is often used to market wines from different locations. Savatiano (Vitis Vinifera L.), is the dominant indigenous variety of the Mesogeia – Attiki region, reaching a percentage of 70% of the total vine cultivation, and being the most widely planted variety in Greece. In this context, this research focuses on the evaluation of the impact of different terroirs within the PGI Attiki zone on the aromatic profile of Savatiano.

Vineyard yield estimation brings several advantages to the entire wine industry. It can provide useful information to support decision making regarding bunch thinning practices, harvest logistics and marketing strategies, as well as to manage stored wine and cellar tanks allocation. Today, this estimation is performed mainly using manual methods based on destructive bunch sampling.

Service crops in vineyard can provide multiple ecosystem services but they can also lead to competition with the grapevine for soil resources in the Mediterranean region due to potential severe droughts (Garcia et al., 2018). One of the levers of action to manage this competition is the choice of species adapted in terms of growth dynamics and water and nutrients’ needs. The objectives of this study were to determine the effect of temporary service crops on grapevine water and nitrogen status and grapevine yield and yield components in a Mediterranean vineyard.