Plant performance and crop yield are negatively affected by drought and heat in the context of the global climate changes. The present study was carried out to the National Institute for Research and Development Brasov, Romania, to observe the tolerance of three potato varieties to in vitro water stress. In vitro water stress negatively affects leaf size and number, number of internodes, stem and root length.Microbuts resulting from uninodal segmentation of in vitro-developed plantlets were inoculated into tubes containing Murashige-Skoog medium, enriched with naphthyl acetic acid and 20 g / l sugar and various amounts of agar.A high reduction of morphological parameters was observed to Castrum variety, susceptible for water deficit, while Ervant variety is more tolerant to drought than the other two varieties. The results indicated that simulation of drought stress under in vitro conditions constitutes a convenient way to study the drought effects on potato plants
