MODELLING SOIL WATER CONTENT AND GRAPEVINE GROWTH AND DEVELOPMENT WITH THE STICS CROP-SOIL MODEL UNDER TWO DIFFERENT WATER MANAGEMENT STRATEGIES

Background and aims: Many models have been developed to evaluate crop growth and development, but few are capable of simulating grapevine systems. The present study was carried out to evaluate the ability of the STICS model to represent grapevine phenology, biomass production, yield and soil water content in two situations differing with respect to rainfall distribution and water management strategies. Methods and results: Simulations were performed for an irrigated vineyard in Chile and an irrigated and a non-irrigated vineyard in France. The crop model gave a good estimation of the main stages of grapevine phenology (less than six days difference between simulated and observed values). Soil water content was the best simulated variable (R2 = 0.99), whereas grapevine evapotranspiration observed only in Chile (R2 = 0.43) and leaf area index observed only in France (R2= 0.80) were the worst simulated variables. Biomass production, yield and their components were correctly simulated (within the 95 % Student confidence interval around the mean observed value). A comparison of the fraction of transpirable soil water and vine water potential measurements with the water stress indices calculated by the STICS model showed that the time and duration of the grapevine water stress period was correctly estimated. Conclusions: Therefore, the STICS model was reasonably successful in simulating vine growth and development, and identifying critical periods concerning the vine water status. Significance of the study: The STICS model can be used to evaluate various water management strategies and their impacts on grape production.