South Africa Wine Research Projects

2. VITICULTURE RESEARCH PROJECT IN PROGRESS

DEMONSTRATION OF PLANT-BASED IRRIGATION ON WINE-GRAPE PERFORMANCE AND QUALITY IN THREE CLIMATICALLY DIFFERENT REGIONS

FShip Water 2 Dr Vink Lategan, Department of Soil Science, Stellenbosch University

Start date: 2019 Flagship Project

AIM AND INDUSTRY RELEVANCE: Previous research has shown that wine grapes need 250 to 350 mm irrigation water for optimum yield. However, this was primarily determined for vineyards in the coastal region under normal winter and spring rainfall conditions. Consequently, it needs to be established if these irrigation amounts will be sufficient in the warmer, drier grape growing regions, and if not, to what extent they should be adjusted. The objective of this study is to develop guidelines based on grapevine water status for wine grape irrigation. In order to apply the minimum irrigation requirement, sound irrigation scheduling practices are essential. This project will be conducted in the form of demo plots in established commercial vineyards, in three climatically different areas (Stellenbosch, Breedekloof and Olifants River). Irrigation scheduling will be done based on plant water potential values based on previous research and compared to the grower’s normal scheduling practice. The effect of the treatments on vegetative parameters, yield and water use efficiency will be evaluated. Since this project will be carried out in a number of vineyards, it is an ideal opportunity to validate remote sensing systems, e.g. satellite or drone images, for application in a variety of commercial vineyards. Experimental wines will also be made and evaluated while economic factors will also be considered. The knowledge on grape and wine responses will empower growers to save irrigation water while obtaining the best wine quality and maximum profit.

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SOUTH AFRICA WINE RESEARCH 2024