Vitis vinifera L. adapts well to a scarce availability of water in the soil. However, in recent decades, the combination of thermal stress with prolonged water scarcity could have dramatic consequences on the vine’s physiological status. In this paper, we evaluated the effects of two canopy shapes and two irrigation regimes at veraison on vine physiology, yield parameters and grape composition through biochemical and molecular approaches. The water shortage strongly influenced the physiology of Sangiovese only when the stress was moderate to severe. Neither the water stress limited to veraison nor the canopy shape were able to influence the yield parameters and sugar content, and a strong induction of the expression of the genes involved in the biosynthesis of anthocyanins was recorded only in conditions of moderate-to-severe stress. This phenomenon led to an increase in the anthocyanin content in berry skins until the end of veraison. Conversely, no significant effects occurred in terms of biochemical and molecular performance after re-watering and at harvest. Though the shape of the canopy could play a role only under elevated temperature and prolonged drought, severe water stress can affect the vine physiology and berry ripening during the veraison stage.

Vineyard mechanical winter pruning has been spreading worldwide, and the physiological basis ascribable to it has been consolidated throughout the years. Despite labor savings and reduction of costs having been proven, the demonstration of its economic viability might be challenging. In this context, this work aims to evaluate the vine performances and the costs of different degrees of the mechanization of winter pruning over a five-year trial (2011–2015). In a vineyard of cv. Trebbiano Romagnolo (Vitis vinifera L.) located in northern Italy, three pruning treatments were laid out as follows: (a) manual pruning (MAN); (b) mechanical pre-pruning and simultaneous manual follow-up (MP + F); (c) mechanical pruning without a manual follow-up (MP). The results showed a strong increase in the node number of MP. Nevertheless, the yield compensation factors (i.e., the shoot fruitfulness and cluster weight) limited the increase in productivity. Soluble solids did not differ between the pruning treatments, while titratable acidity resulted slightly higher only on the MP berries. The MP treatment was the most economically convenient, with a vineyard surface of 1.5 hectares, while mechanical pruning with manual finishing resulted more advantageous, compared to manual pruning when the vineyard surface was greater than 2.9 hectares. The agronomic and economic results obtained in this five-year trial suggest that mechanical pruning may be profitably applied also on grapevine varieties characterized by low basal bud fruitfulness, such as Trebbiano Romagnolo.

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One of the first effects of climate change in wine-growing areas is the advancement of phenological stages, especially concerning early berry ripening. In this condition, the decoupling between technological and phenolic maturity often occurs. Anthocyanins in red grapes are among the compounds that mostly contribute to phenolic maturity. However, their accumulation in the grape berries is known to be impaired by high temperatures. Therefore, this study aims to evaluate the efficacy of mineral-based compounds treatments with kaolin and zeolite, based on chabasite, on the enhancement of anthocyanins accumulation, also at the molecular level, analysing the gene expressions along the flavonoid biosynthesis pathway during ripening of Sangiovese berries. In addition, the temperature of berries and grape leaves, vine water status, leaf photosynthetic efficiency, total soluble solids, titratable acidity and pH were measured throughout the growing season. Hence, in the current study, it has been demonstrated the efficacy of kaolin and zeolite treatments not only in lowering the daily maximum grape berries temperature but also in the improvement of grapes anthocyanins accumulation correlated with the enhancement of expression of those genes involved in their biosynthesis pathway. Moreover, treatments had no significant effect on productive parameters.

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