Responses of young Punica granatum plants under four different water regimes

We studied the effect of four irrigation treatments, expressed as fractions (1.3, 1.0, 0.7 and 0.3) of crop evapotranspiration (ETc), on the growth of young pomegranate plants in central Chile (32 degrees 32' S and 71 degrees 06' W). We evaluated the effect of the four treatments on canopy volume (CV) during two growing seasons. For 28 days during the second growing season, we evaluated soil moisture content (0), the soil-moisture depletion factor (p), trunk cumulative growth (TCG), trunk growth rate (TGR) and maximum daily trunk shrinkage (MDS). We found relationships between CV and TCG and between CV and TGR. There were no differences in MDS among the irrigation treatments. We observed significant water stress in plants in the 0.3 ETc treatment (p = 0.47). The highest growth was observed in plants in the 1.3 ETc treatment, which suggests that the crop coefficient (Kc) was underestimated.