Pedological factor influence on the viticultural zoning of the Aljarafe Alto (Seville, Spain)

In recent years, Uruguay has embraced the Albariño grape variety (Vitis vinifera L.) as one of the most promising for commercial growth. Originally cultivated in Galicia and northern Portugal, Albariño has risen to prominence in the global wine market, driving strong demand and significantly increasing grape prices [1].

Oenococcus oeni is the main Lactic Acid Bacteria responsible for malolactic fermentation, converting malic acid into lactic acid and carbon dioxide in wines. Following the alcoholic fermentation, this second fermentation ensures a deacidification and remains essential for the release of aromatic notes and the improvement of microbial stability in many wines. Nevertheless, wine is a harsh environment for microbial growth, especially because of its low pH (between 2.9 and 3.6 depending on the type of wine) and nutrient deficiency. In order to maintain homeostasis and ensure viability, O. oeni possesses different cellular mechanisms including organic acid metabolisms which represent also the major pathway to synthetize energy in wine.

Climate change is causing a gap between the technological and phenolic maturity of grapes, resulting in wines with high alcohol content and low polyphenol concentration. Another phenomenon associated with high temperatures and whose effect is more pronounced if the harvest is delayed is the decrease in the acidity of the grapes, mainly in malic acid, and an increase in pH caused by the accumulation of potassium derived from the increase in temperature. Therefore, climate change and the effects it causes on the vine leads to unbalanced wines, with high alcohol content and lack of color, with green tannins, astringency and excessively low acidity if not corrected.

Plasmopara viticola, the causal agent of downy mildew (DM), and Uncinula necator, the causal agent of powdery mildew (PM), are two of the main phytopathogenic microorganisms causing major economic losses in the primary sector, especially in the wine sector, by wilting bunches and leaves with a consequent decrease in the photosynthetic rate of the plant and in the annual yield. Currently, the most widespread methods for planning spraying are based on the 3-10 rule, which states that the first application should take place when: (i) the air temperature is greater than 10°C; (ii) shoots are equal or greater than 10 cm; and (iii) a minimum of 10 mm rainfall within 24–48 hours has occurred, or at the beginning of the bud break with periodic applications according to the manufacturer’s instructions.

Brazil is one of the few countries where vineyards of Vitis labrusca and Vitis vinifera coexist in the same geographical spaces, due to complex processes of territorial occupation by successive waves of European settlers.