Modeling Phenology, Water Status, and Yield Components of Three Portuguese Grapevines Using the STICS Crop Model

Abstract

Viticulture plays a key role in Portuguese economic growth. The possibility of obtaining early predictions of viticultural parameters, such as phenology, water status, yield, and potential wine characteristics, are of great value for growers and will influence the viticultural chain. The present study is a first approach to adapt the Simulateur mulTIdisciplinaire pour les Cultures Standard (STICS), a dynamic crop model, to Portuguese winegrowing conditions and grapevine varieties. Several site-specific parameters for climate, soil, and management practices were assessed. Varietal-specific parameters were measured from vineyards in the Douro and Lisboa winegrowing regions of Portugal. Three of the most important varieties in the country (Aragonez, Touriga-Franca, and Touriga-Nacional) were targeted for model calibration. Overall, the STICS crop model was successful in simulating yield, phenological stages, and water stress, but not alcohol content. The relatively high model accuracy will improve the performance of vineyard operations and winemaking practices, such as organizing harvests, vineyard intervention scheduling, irrigation procedures, and strategic planning of wineries. STICS may be feasible as a decision support tool for short- and long-term strategic planning in Portuguese viticulture, particularly taking into account the projected impacts of climate change. The efficiency gains obtained from the use of this crop model by wine industry stakeholders is expected to increase the competitiveness and sustainability of the wine sector in Portugal.