Photosynthetic resilience of dry‐farmed ‘Pedro Ximénez’ grapevines under organic versus conventional management in a warm
Mediterranean
vineyard
Saray Gutiérrez‐Gordillo, Juan Manuel Pérez‐González, Pau Sancho‐Galán, Antonio Amores‐Arrocha, Ana Jiménez‐Cantizano Abstract
BACKGROUND
Organic viticulture is expanding across Mediterranean wine regions, driven by EU sustainability policies and increasing consumer demand. However, comparative studies assessing both physiological performance and productivity of grapevines under organic and conventional management while maintaining similar soil and climatic conditions remain limited, particularly in dry‐farmed warm Mediterranean environments. This study evaluated the physiological and agronomic responses of the grapevine cultivar ‘Pedro Ximénez’ over two consecutive seasons (2022–2023) in a commercial dry‐farmed vineyard in south‐western Spain managed under certified organic and conventional management systems.
RESULTS
Leaf gas‐exchange parameters including net photosynthetic rate ( A N ), stomatal conductance ( g s ), intrinsic water‐use efficiency ( i WUE), and the stomatal stress integral ( SI gs ) were monitored alongside agronomic parameters such as bunch number, bunch weight, and pruning weight. Across both seasons, organically managed vines showed lower cumulative stomatal stress ( SI gs reduced by 37% in 2022 and 14% in 2023) while maintaining similar seasonal iWUE values. During high vapor pressure deficit episodes, electron transport rate (ETR) remained comparable between management systems whereas A N declined, indicating that photosynthetic reductions were mainly associated with CO₂ diffusional or biochemical limitations rather than photochemical impairment. Yield components were comparable between systems, although organic vines produced more clusters per plant in 2023 (17 ± 0.9 vs 15 ± 0.8; Tukey test, P < 0.05).
CONCLUSION
Under the conditions of this commercial, warm Mediterranean vineyard, organic management was associated with reduced seasonal stomatal stress while maintaining comparable productivity, suggesting that organic viticulture may represent a viable strategy for dry‐farmed vineyards in warm Mediterranean regions. © 2026 Society of Chemical Industry.