Under standard wine tasting conditions, volatile organic compounds (VOCs) responsible for the wine’s bouquet progressively invade the chemical space perceived by the consumer in the glass headspace.

Grapevine (Vitis vinifera) is amongst the world’s most cultivated fruit crops, and of global and economic significance, producing a wide variety of grape-derived products, including wine, and table grapes. The genus Vitis, encompassing approximately 70 naturally occurring inter-fertile species, exhibits extensive genetic and phenotypic diversity, highlighted by the global cultivation of thousands of predominantly Vitis vinifera cultivars. Despite the importance of harnessing its naturally occurring genetic diversity to pursue traits of interest, especially considering the continued and growing demand for sustainable high-quality grape production, the systematic characterization of available functional genetic variants remains limited.

Stomata are microscopic pores mainly located in leaf epidermis, allowing gas exchanges between plants and atmosphere. Stomatal initiation relies on the transcription factor SPEECHLESS which is mainly regulated by the MAP kinase cascade, in turn controlled by small signaling peptides, the Epidermal Patterning Factors (EPF and EPF-Like), namely EPF1, EPF2 and EPFL9. While EPF1 and EPF2 induce the inhibition of SPEECHLESS, their antagonist, EPFL9, stabilizes it, leading to stomatal formation. In grapevine, there are two paralogs for EPFL9, VviEPFL9-1 and VviEPFL9-2. Despite their structural similarity, it remains unclear whether they are differentially regulated and have distinct roles.

Bobal is the second most widely grown Spanish red grape variety (54,165 has), mainly cultivated in the Valencian Community and especially, in Utiel-Requena region (about 67% of 34,000 has). In this study, agronomic and enological parameters were determined in 98 biotypes selected during 2018 and 2019 in more than 50 vineyards over 50 years-old in the Utiel-Requena region. Moreover, a multi-criteria approach considering temperature and rainfall (Fig. 1A), among other parameters, was made to establish three different zones within the region (Fig. 1B), where in the future the selected biotypes will evaluated. In fact, in 2020, 4 replicates and 12 vines per biotype were planted in an experimental vineyard to preserve this important intra-cultivar diversity.