New breeding frontiers: application of the CRISPR-cas9 system in grapevine (V. vinifera L.) and improvements in plant regeneration

Cognac spirit aromas result from the presence of a wide variety of volatile odorous compounds associated with the modalities of distilled spirit elaboration and during aging. Indeed, these odorous compounds play an essential role in the finesse and complexity of the aged Cognac.

Context and purpose of the study. Heatwaves have become more frequent and intense in several winegrowing regions.

AIM: We investigated the effect of soil texture on grapevine response to water stress, leaf abscisic acid concentration and berry quality, in two adjacent vineyards located in the renewed Cannubi hill of Barolo (Langhe area, CN, North-West Italy).

The parameters that determine the grape quality, and therefore the optimal harvest time, suffer variations during berry ripening, related to climate change, with the widely known problem of the gap between technological and phenolic maturities. However, there are few studies about its incidence on grape nitrogen composition. For this reason, the use of an elicitor, methyl jasmonate (MeJ), alone or with urea, is proposed as a tool to reduce climatic decoupling, allowing to establish the harvest time in order to achieve the optimum grape quality. The aim was to study the effect of MeJ and MeJ+Urea foliar applications on the evolution of Tempranillo amino acids content throughout the grape maturation. Three treatments were foliarly applied, at veraison and 7 days later: control (water), MeJ (10 mM) and MeJ+Urea (10 mM+6 kg N/ha). Grape samples were taken at five stages of maturation: day before the first and second applications, 15 days after the second application (pre-harvest), harvest day, and 15 days after harvest (post-harvest). The amino acids analysis of the samples was carried out by HPLC. Results showed that the evolution of amino acids was similar regardless of the treatment; however, foliar applications influenced the nitrogen compounds content, i.e., there was no qualitative effect but quantitative one. Most of the amino acids reached their maximum concentration in pre-harvest, being higher in grapes from the treatments than in the control. In general, no differences in grape amino acids content were observed between MeJ and MeJ+Urea treatments. Foliar applications with MeJ and MeJ+Urea enhanced the grape amino acids content, without affecting their profile, helping to optimize their quality and allowing to establish a more complete grape ripening standard. Therefore, MeJ and MeJ+Urea foliar applications can be a simple agronomic practice, which has shown promising results in order to enhance the grape quality.

In response to increasing societal demands for environmentally-friendly viticulture, winegrowers are adapting their cultivation techniques, particularly by reducing the use of herbicides.