In semi-humid climate, spatially resolved analysis of water deficit was carried out in apple orchard (Malus x domestica 'Pinova'). The meteorological data were recorded daily by a weather station. The apparent soil electrical conductivity (ECa) was measured at field capacity, and twenty soil samples in 30 cm were gathered for texture, bulk density, and gravimetric soil water content analyses. Furthermore, ten trees were defoliated in different ECa regions in order to estimate the leaf area ratio (LAR).

The crop evapotranspiration (ETc; mm/d) was computed by multiplying the actual evapotranspiration (ETa; mm/d) and considering the soil water stress coefficient (Ks), soil surface evaporation coefficient (Ke) and LAR. These values were implemented in the Geisenheimer irrigation model for calculating the water deficit using crop coefficient (Kcb) in the crucial developmental stages: full bloom, cell division stage, and harvest. A positive correlation was observed between the ECa and total available water content in the root zone (r = 0.78, p<0.05). Furthermore, the influence of LAR on the water balance was quantified, pointing to the reasonability of spatially resolved water balance.