Hybrid Grapes for a Sustainable Viticulture in South Italy: Parentage Diagram Analysis and Metal Assessment in a Homemade Wine of Chambourcin Cultivar
The aim of this work was to explore a more sustainable approach in the viticulture of Mediterranean countries that could derive from growing hybrid grape varieties inheriting tolerance/resistance characters from the wild vines utilized for their selection. Among the plethora of hybrid grapes developed in the last decades, some are able to produce high-quality wines whose flavor resembles European varieties, thus overcoming a typical limit of several old hybrids based on V. labrusca whose wine was characterized by a distinctive wild flavor. In this context, we examined some characteristics of Chambourcin, one of the most promising hybrid cultivars producing quality red wine and requiring much less phytosanitary interventions than European grapevine. In detail, the scope of this study included the investigation of the parentage diagram for this hybrid grape variety and the chemical analysis of a Chambourcin wine produced in South Italy. We filled the gaps corresponding to some of the Vitis ancestors participating in its complex pedigree by means of a literature analysis and a mathematical approach. We found high ancestry of V. vinifera (about 41%), followed by V. berlandieri (about 28%), V. rupestris (about 19%) and to a lesser extent other American wild vines. The significant content of V. berlandieri and V. rupestris genome in Chambourcin explains the considerable resistance of this variety to the two main pathogens affecting grapevines, i.e., downy mildew and powdery mildew. We then analyzed an organic Chambourcin wine produced in South Italy from grapes obtained without any phytosanitary treatment by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) in order to assess heavy metal content and found it comparable to other (red and rosè) V. vinifera wines obtained from family-run vineyards. Heavy metals contents detected were not of concern for any of the wines analyzed, however, copper accumulation in V. vinifera vineyard soils, and pollution deriving from other phytosanitary chemicals remain issues that in the case of Chambourcin vineyards could be solved at least in large part.