Aims:The aim of this work was to verify the influence of mechanical harvesting and postharvest treatments on wine composition. Methods and results:Trials were carried out in triplicate on cv. Montuni grapes. The estimated best setting frequency for the mechanical harvester was 410 shakes/min. Comparing hand-picked and mechanically harvested grapes, the reduced extract and pH results were lower for the hand-picked grapes, showing a more evident berry breakage caused by the mechanical harvester. The wines obtained from mechanically harvested grapes had a lower phenolic compound content than wines produced with hand-picked grapes, indicating that oxidation phenomena occurred; the trend for postharvest treated grapes was different. The significantly lower amount of higher alcohols in the hand-picked grapes trial than in the mechanically harvested ones could be explained by a lower amount of their precursors and oxygen in musts. The sensory differences among the trials were significant for some parameters, but an overall view of the data suggested that the differences were not remarkable and all the wines were good. Conclusion:Postharvest treatments reduce the loss of natural antioxidant compounds found in wines produced from mechanically harvested grapes. Mechanical harvesting does not have a negative influence on wine composition if matched with the proper vineyard characteristics, machine settings and postharvest treatments. The typicality of Montuni wine is maintained in the cases of grapes harvested mechanically with, but also without, any postharvest treatment. The use of these treatments is otherwise useful to obtain wines with a better stability.Significance and impact of the study: With respect to mechanical harvesting, this study highlights the importance of maintaining and/or improving the quality of mechanically harvested grapes containing the harvesting costs. Conclusion :Les traitements après vendange réduisent la perte des composés antioxydants naturels dans les vins issus de raisins récoltés mécaniquement. La vendange mécanique n'a pas une influence négative sur la composition des vins, si on prend en compte les caractéristiques du vignoble, les réglages de la machine à vendanger ainsi que les traitements après la vendange. La typicité du vin issu du cépage Montuni est conservée dans le cas de vendanges mécaniques, avec, mais aussi sans, traitements après vendange. L'usage de ces traitements est utile pour obtenir des vins ayant une meilleure stabilité.Signification : Cette étude a souligné l'importance de maintenir et-ou d'améliorer la qualité des raisins récoltés à la machine, en limitant les dépenses liées à la vendange. AbstractRésumé manuscript

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A mathematical model was developed to get an equation of the decrease of air velocity crossing the canopy of tree crops during pesticide application using air carrier orchard sprayers. The utility of such a model rises from the need for an aid to understand the experimental results of several authors, who agree with the opinion that air jet velocity greatly affects environmental pollution from pesticides. Further, probably in the future it will arise the demand to implement the equation of air velocity decay in self-adjustment systems of the fan installed on orchard sprayers to limit spray drift. Based on momentum theorem applied under three assumptions, a differential equation was found and its integration lead to a closed 1282 Dario Friso et al. solution that can easily be implemented in a PLC for the self-adjustment system to develop. The integral equation thus obtained, together with the assumptions made, was submitted to on-field verification on three crops (peach, vine and apple). The results show a good correspondence between measured and estimated air speed as predicted by the mathematical model, with a relative mean error 3.3% and a maximum value of 6.2%.

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