Coping with extreme climatic events: some lessons from recent work on grapevine under heat peak

The global consumption of wine has undergone significant changes after several years of covid-19, which was the beginning of a global crisis of the current century. This pushed some people to start looking for comfort and security as they felt that the world around them was losing these benefits. In most cases, this has led to them to idea of rethinking their lives in an attempt to live better or continuing to stay true to their habits and lifestyles despite the pressure of changes. Alcohol in any form is a part of these reactions, leading to increased consumption in the early stages of a crisis, particularly in relation to anxiety.

Several classes of flavonoids, such as anthocyanins, flavonols, flavanols and flavones, undergo a slow H/D exchange on aromatic ring A, leading to full deuteration at positions C(6) and C(8). Within the flavanol class, H-C(6) and H-C(8) of catechin and epicatechin are slowly exchanged in D2O to the corresponding deuterated analogues; even quercetin, a relevant flavonol representative, shows the same behaviour in a D2O/DMSOd6 1:1 solution. Detailed kinetic measurements of these H/D scrambling processes are here reported by exploiting the time-dependent changes of their peak areas in the 1H-NMR spectra taken at different temperatures. A unifying reaction mechanism is also proposed based on our detailed kinetic observations, even taking into account pH and solvent effects. Molecular modelling and QM calculations were also carried out to shed more light on several molecular details of the proposed mechanism.

Irrigation of vineyards is a matter of controversial arguments at areas of high quality wine production. Besides, the effects of the water in the plant are closer related to the water availability than to the irrigation regime.

Among the different strategies used in vine growing to fight against mold diseases, it can be pointed out the hybridation of traditional grape varieties with others, presenting a genetic resistance to pathogen attack. The research in this field has been encouraged in recent years due to the increased concern about human safety and environmental pollution linked to the use of agrochemicals. This approach allows to limit the number of treatments and the type of active compounds used in vine management. The environment determines the pressure degree of the diseases on vines and the biologic response of the plant to their attack.

Grapevine (Vitis spp.) is a globally significant fruit crop and enhancing its agronomic and oenological traits is crucial to meet changing agricultural conditions and consumer demands.