Delaying berry ripening of Bobal and Tempranillo grapevines by late leaf removal in a semi-arid and temperate-warm climate under different water regimes

Background and Aims: Climate change is advancing grape ripening and decoupling sugar and phenolic maturity, impacting wine typicity. The aim of this study was to test whether late leaf removal (LLR) under different watering regimes delayed harvest of two Spanish red cultivars in a semi-arid and temperate-warm climate. Methods and Results: In two trials carried out in eastern Spain with the Bobal and Tempranillo cultivars, vines were partially defoliated above the bunch zone shortly before veraison under rainfed and deficit irrigation conditions during two seasons. The rate of grape ripening in both cultivars was significantly affected by LLR under either watering regime, consequently delaying harvest. Vine water status and leaf photosynthetic rate were improved by LLR. The reduction in leaf area-to-fruit ratio resulting from the LLR treatments was found to be more limiting for the accumulation of anthocyanin than for TSS. Consequently, LLR negatively affected wine colour intensity. In addition, yield was constrained by LLR in Tempranillo due to a reduction in bunch and berry mass. Conclusions: The reduction in the rate of accumulation of grape TSS provoked by LLR did not necessarily result in a more balanced berry maturity. The effectiveness of the LLR technique appears to depend on its final impact on leaf area-to-fruit ratio and vine water status, the cultivar photosynthetic compensation capacity and the environmental conditions. Significance of the Study: Late leaf removal might not be effective for coupling anthocyanin and TSS in berries under moderate water stress conditions, given the observed reductions in red wine colour

Climate change trends, grape production, and potential alcohol concentration in wine from the "Romagna Sangiovese" appellation area (Italy)

The trend of climate change and its effect on grape production and wine composition was evaluated using a real case study of seven wineries located in the \u201cRomagna Sangiovese\u201d appellation area (northern Italy), one of the most important wine producing region of Italy. This preliminary study focused on three key aspects: (i) Assessment of climate change trends by calculating bioclimatic indices over the last 61 years (from 1953 to 2013) in the Romagna Sangiovese area: significant increasing trends were found for the maximum, mean, and minimum daily temperatures, while a decreasing trend was found for precipitation during the growing season period (April\u2013October). Mean growing season temperature was 18.49 \ub0C, considered as warm days in the Romagna Sangiovese area and optimal for vegetative growth of Sangiovese, while nights during the ripening months were cold (13.66 \ub0C). The rise of temperature shifted studied area from the temperate/warm temperate to the warm temperate-/warm grape-growing region (according to the Huglin classification). (ii) Relation between the potential alcohol content from seven wineries and the climate change from 2001 to 2012: dry spell index (DSI) and Huglin index (HI) suggested a large contribution to increasing level of potential alcohol in Sangiovese wines, whereas DSI showed higher correlation with potential alcohol respect to the HI. (iii) Relation between grape production and the climate change from 1982 to 2012: a significant increasing trend was found with little effect of the climate change trends estimated with used bioclimatic indices. Practical implication at viticultural and oenological levels is discussed

Assessing local climate vulnerability and winegrowers’ adaptive processes in the context of climate change.

International audienc

Yeast Ecology of Wine Production

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