The influence of water deficit on self-rooting vitroplants of clone PB260 regenerated by somatic embryogenesis was investigated. Physiological responses including transpiration, stomatal conductance and fluorescence were monitored on leaves. Osmoprotectant compound like pro lin e, antioxidants and reactive-oxygen speciesscavenging enzymes like ascorbate peroxidase, glutathione reductase were analyzed during the stress. These responses are used io determine defence mechanism involved in drought tolerance and identifY parameters to be used as indicators in breeding programme or for genetic modification.