Plantlets of P. euphratica (clone B2) were obtained by in vitro culture. After ex vitro acclimation, they were transferred and acclimated to greenhouse conditions and transplanted into 7.5L-pot filled with peat-sand mix (50/50 V/V) and were pruned (following some leaf shedding due to transplantation shock). In the greenhouse, climate conditions depended on outside weather but temperature was regulated in order to remain between 15 and 30°C. A moderate, increasing drought stress was applied and controlled for 6 weeks. Soil volumetric water content was measured one to two times a day depending on the intensity of the stress (TDR and weighting). Plantlets were progressively brought to 5 stress levels [soil volumetric water content]: 10% (harvest 1, 11 days from start of experiment), 7.5% (harvest 2, 16 days from start of experiment), 5% (harvest 3, 22 days from start of experiment), 4% (harvest 4, 26-32 days from start of experiment) and back to fully available water (harvest 5, 10 days after fully watering of the trees; 36 days from start of experiment). Leaves and roots (including control and stressed trees) were harvested for each stress level. At harvest 1-3, samples from five trees were harvested. At harvest 4, samples from two trees were harvested at each of day 26, 29 and 32. At harvest 5, samples were harvested from two control trees and four re-watered trees.