Climate projections over France wine-growing region and its potential impact on phenology

This study presents the preliminary results obtained in 2022, of the evaluation of three new crossbreed winegrape genotypes and their parental varieties, grown under controlled irrigation (60% ETc) and rainfed conditions in a wine-growing area with scarcity of water and high temperatures (Murcia, southeast Spain). The genotypes MC16 and MC80 were obtained from crosses between the varieties ‘Monastrell’ and ‘Cabernet Sauvignon’, and MS104 from crosses between ‘Monastrell’ and ‘Syrah’ [1]. The objective of this study was to analyse the physiological response and vegetative development of the 6 genotypes under the two irrigation conditions, and to study their effect on the content of soluble sugars and chlorophyll in the leaf.

Aim: Temperature corresponds to one of the main terroir factors influencing grapevine physiology, primarily evidenced by its impact on phenology. Numerous studies have aimed at expressing time with thermal indices such as growing degree days (GDD) and have thus enabled a better modelling of grapevine responses to temperature. However, some works have highlighted the need to adapt

In the last decades the growers of the Portuguese Dão winegrowing region (center of Portugal) are experiencing changes in climate that are influencing either grape phenology berry health and ripening. Aiming to study the relationships between climate indices (CI), seasonal weather and grapevine phenology, in this work long-term climate and phenological data collected at the experimental vineyard of the Portuguese Dão research centre between 1958 and 2019 (61 years) for the red variety Touriga Nacional, was analyzed. The trends over time for the classical temperature-based indices (Growing Season Temperature – GST -, Growing Degree Days – GDD, Huglin Index – HI and Cool Night Index – CI) presented a significantly positive slope while the Dryness Index (DI) showed a negative trend over the last 61 years. Regarding grapevine phenology, an average advance of 4.5 days per decade in the harvest day was observed throughout the last 61 years. Consequently, the weather conditions during the ripening period have changed, showing an increasing trend over time in the average temperature (higher magnitude in the maximum than in the minimum temperature) and a decrease in the accumulated rainfall. A regression analysis showed that ~50% of harvest date variability over years was explained by the temperature-based indices variability. These observed effects of climate change on bioclimatic indices and corresponding anticipation of harvest date can still be considered advantageous for the Dão terroir as it allows to achieve an optimal berry ripening before the common equinox rains and, therefore, avoid the potential negative impacts of the rainfall on berry health and composition.

Parallèlement à la connaissance des aptitudes viticoles, le terroir témoigne d’une identité locale, d’une spécificité des conditions de productions et d’une originalité des lieux.

The conceptual image of a wine related to the terroir has consequences in technical terms. Among factors affecting the typicality, producers put forward the environmental factors of the terroir system