Winemaking terroir – the guideline for choosing of grape rootstocks for soils with different characteristics

Abstract

The selection of rootstocks is one of the first and most important stages in the establishment of grape plantations under grafted conditions, which determines the productivity of rootstock-scion combinations and the further chain of design solutions: spatial placement of rows on the land plot, accompanying the production process of agronomic and agrochemical methods. Given the high importance of terroir factors for viticulture and winemaking, we were aware of the need to consider them in detail at this design stage. The aim was to create an algorithm for selecting varieties based on local terroir factors and apply it to the design of vineyards. Based on the analysis of literary sources and the agronomic experience of viticulture and winemaking specialists, we have identified key stress factors that in general, should be taken into account when selecting varieties of rootstocks. Based on the results of a comprehensive study of terroir and analytical diagnostics of soil samples taken on a land plot located in the Bakhchisaray district of the Republic of Crimea, local stress factors representing risks were clarified and prioritized neo-medially at the site of testing the landscape-adapted approach to the selection of rootstocks: carbonate condition, risk of phylloxera infestation, high content of fine fractions in granulometric composition, short-term droughts, risk of local overwatering, phosphorus deficiency. In total 20 the most common commercial varieties of rootstocks were considered for each selected soil area. The sample reduction scenario, based on the prioritization of the above stressors, reduced the number of varieties considered to three variants: 1103 Paulsen, 140 Ruggeri, and Fercal, which were scored against each other and considering the local terroir conditions of the plot, for further comparison in terms of market and logistics in making the final design decision.