Crop simulation models represent useful tools for enhancing agricultural research through the integrated analysis of the relations between soil, plant and environment. At the same time, they can provide effective support for decision making in agricultural planning by modelling the impact of several treatments on crop yield, soil fertility and environmental water resources. The Southern Italy is characterised by low water availability due to scarce and irregular rainfall and high evaporative of the atmosphere. In the last twenty years, several models have been developed for the simulation of water fluxes and solute transport in the groundwater-soil-crop-atmosphere continuum. One of these is SWAP (Soil-Water-Atmosphere-Plant), a physical based model that resolves numerically the Richards equation in order to describe the water flux into the soil profile. It integrates the water flow with the solute transport, taking account of soil heterogeneity, crop growth and drainage at various spacing levels. Concerning the crop growth, SWAP model includes three crop growth routines consisting in a simple model and two detailed other ones for grass and other erbaceous crops deriving both from the crop model WOFOST. The aim of this work is to apply SWAP/WOFOST model for simulating water flow and solute transport into the soil and to evaluate different irrigation strategies in order to optimize the use of water resources characterized by different salinity levels and to preserve the soil to salt accumulation. For this purpose several irrigation strategies were defined including different scheduling and salinity levels of water irrigation. In a sequence of ten year, such strategies were applied for sorghum cultivation under two different groundwater conditions: (i) a fix watertable at 6 m depth (DG) and (ii) a fluctuant and shallow watertable from 0 to 3 m depth (SG). The data-set used for the calibration and validation was collected from a long-period research carried out in an experimental farm located in Metaponto (Italy) within the ionical coastal zone in Southern Italy. This area is characterized by a Mediterranean climate, clay soils and groundwater conditions very similar to those utilized in the scenario analysis. The data-set included Sorghum crop and soil data concerning crop phenology and growth, soil water content and hydraulic properties. Moreover, the scenario analysis was performed by utilizing the meteorological data-set collected in the same experimental farm. The two bottom boundary conditions influenced significantly the seasonal fluxes of the soil water balance. The irrigation amounts were higher for DG than SG scenarios that was characterized by an higher upward flux from the watertable and, above all, by an higher soil water content at the crop sowing time. For DG scenarios, in the first part of the cycle an higher soil evaporation was also detected because of the first irrigations that wetted the soil surface. These results coupled with those concerning the impact of the salinity of water irrigation allowed to individuate the agronomical practices that can alleviate the negative effects of saline irrigation waters on growth and crop yield.