Methodology to assess vine cultivation suitability using climatic ranges for key physiological processes: results for three South African regions

Context and purpose of the study. The concept of terroir encompasses the investigation of the physical environment’s influence on grapevine physiology, grape composition, and wine quality, with an emphasis on employing viticultural zoning techniques to systematically characterize and analyze terroirs.

The recovery of ancestral or minority vine varieties has been gaining great interest in recent years, among other reasons because it is likely that some of these varieties, due to the fact that they are found in relict areas, have a greater potential for adaptation to external factors (biotic or abiotic) and can minimize the effects that climate change is causing in viticulture. Varieties that can be grown at altitude are currently being sought to combat rising temperatures and prolonged extreme drought conditions. In Catalonia, the Pyrenean expansion of vineyard cultivation is documented from the 10th century and has been related to the “small climatic optimum” (9th-12th centuries) and also to seigniorial power.[1] But different adverse climatic periods and the arrival of Phylloxera by the late 19th century made many of these crops disappear.[2]

Over the last decades, wine analysis has become an important analytical field, with emphasis placed on the development of new methodologies for characterization and elaboration control.

The communication of the aims of a viticulture under the premise of terroir is presently discussed in a lot of wine-growing regions around the world. To encourage this discussion the differences in knowledge, understanding, and preference concerning wine and landscape should be regarded more closely: the wine should be perceived as a representative of its region and one of the most characteristic features of a region is the landscape.

At CREA – Centro di Ricerca di Viticoltura ed Enologia, based in Velletri (RM), an experimental vineyard including 10 downy mildew resistent/tolerant grape varieties and two susceptible varieties was set up with the principal goal to evaluate the behavoir of these varieties in term of resistance to downy mildew (Plasmopara viticola). This evaluation, together to oenological studies, are necessary to register them also in Regional Register (in Lazio region). Monitoring of behavior towards Plasmopara viticulture of resistant vines were done in 2020 and 2021 at different times (phenological stages) and until harvesting, according to an international standard code BBCH a centesimal phenological scale, based on coding system.