Relationships between chlorophyll content of vine leaves, predawn leaf water potential at veraison, and chemical and sensory attributes of wine

Abstract

Background: Water deficit and iron deficiency (iron chlorosis) are common environmental stresses that affect grapevine production in the Mediterranean area. Studies on the impact of both stresses, when they act simultaneously, are rare. The main objective of this investigation was to evaluate the combined effects of the incidence of iron chlorosis and the vine water status on quality of Tempranillo wine. For this, 20 non-irrigated vineyard subzones (10 m × 10 m each), from non-affected to moderately affected by iron chlorosis, were monitored in the Ribera del Duero area (north-central Spain) during two consecutive seasons. Results: Factorial analyses of variance were performed to study the effects of predawn leaf water potential and foliar chlorophyll content, both measured at veraison, on chemical and sensory characteristics of wine. With an impact much greater than water status, the incidence of iron stress decreased pH of the wine and enhanced sensory attributes as tonality, layer intensity, flavour intensity, and persistence in the mouth. There were increases in red colour, astringency, and persistence of the wine associated with chlorosis, although they might be restricted in water-deficit conditions. Conclusion: The results have demonstrated that mild to moderate iron stress can have positive effects on chemical and sensory attributes of Tempranillo wine. Measurements of foliar chlorophyll content at veraison could be very useful to map quality potential in rainfed vineyards affected by iron deficiency.

Carbonated Irrigation Assessment of Grapevine Growth, Nutrient Absorption, and Sugar Accumulation in a Tempranillo (Vitis vinifera L.) Vineyard

“…The values of osmotically active solutes in grapevines leaves were similar to those that have been documented by other authors [50]. Many studies have reported that drought stress leads to a general depletion of soluble sugars and starch in leaves [57,58] that results in the inhibition of photosynthesis, where stomata close and the internal CO 2 concentration decreases [22,59,60]. Nevertheless, experiments by other authors have reported that soluble sugars accumulate in leaves during drought stress [61].…”

Do Young Consumers Care about Antioxidant Benefits and Resveratrol and Caffeic Acid Consumption?

“…An article discusses how the levels of chlorophyll in the leaves and the amount of water in the leaves before sunrise, measured during the grapes' ripening stage, affect the wine's chemical and sensory properties. The presence of iron stress lowers the pH of the wine and improves sensory qualities like tone, intensity, and flavor, with a greater impact than the water levels [26].…”