Influenza dei fattori dell’ambiente sulla risposta della pianta, e caratteristiche dell’uva della cv tannat prodotta in vigneti di tre zone climatiche dell’Uruguay

Irrigation is an important practice to influence vine quality, especially in Mediterranean regions, characterized by hot summers and severe droughts during the growing season. This study focused on deficit irrigation regime influence on amino acids composition of Monastrell grapevines under semiarid conditions (Albacete, Southeastern of Spain). In 2019, two treatments were applied: non-irrigation (NI) and regulated deficit irrigation (RDI), watered at 30% of the estimated crop evapotranspiration from fruit set to onset of veraison. Grape amino acids content was analyzed by HPLC. Berries from non-irrigated vines showed higher concentration of several amino acids, such as tryptophan (73%), arginine (70%), lysine (36%), isoleucine (27%), and leucine (21%), compared to RDI grapes. Arginine is, together with ammonium ion, the principal nitrogen source for yeasts during the alcoholic fermentation; while isoleucine, tryptophan, and leucine are precursors of fermentative volatile compounds, key compounds for wine quality. Moreover, NI treatment increased in a 14% the total amino acids content in grapes compared to RDI treatment. The reported effects might be because yield was 70% higher in RDI vines than in the NI ones and, therefore, the sink demand was increased in the irrigated vines. In addition, NI vines suffered more severe water stress and it is known that the amino acids synthesis and accumulation can be influenced by the plant response to stress. According to the results, the irrigation regime showed effect on amino acids concentration in Monastrell grapes under semiarid conditions. Grapes from non-irrigated vines showed a higher content of several amino acids relevant to the fermentative process and to the wine aroma compounds formation. It is demonstrated that the final content of nitrogen-related components in grapes is influenced by the irrigation regime. The convenience of the irrigation strategy to suggest will depend on the desired wine style and the target yield levels.

Downy mildew, caused by the oomycete Plasmopara viticola (Berk. & M.A. Curtis) Berl. & De Toni, is one of the most destructive grapevine diseases mostly affecting Vitis vinifera L. and impacting on viticulture. The pathogen invasion can induce in grapevine multiple defense reactions, first PAMP-Triggered Immunity and secondly Effector-Triggered Immunity. Plasmopara viticola can overcome these defense mechanisms through the secretion of effectors, such as RxLR, into the plant cells, making it easier for the oomycete to infect grapevines. Currently, the use of chemical pesticides remains the most effective way to control the pathogen with severe negative side effects on the environment and animal health.

Fifteen nepoviruses are able to induce fanleaf degeneration in grapes. Grapevine fanleaf virus (GFLV) is the main causal agent of this disease

Il tema da trattare si riferisce ai vari ecosistemi viticoli mondiali, ovviamente non facilmente sintetizzabili in una relazione. Sostanzialmente si richiama

Water nutrition is crucial for wine grape performance. Thus soil investigation aims at characterizing spatial and temporal variability of available water. A possible strategy