"A great challenge for potato production in the coming decades is to maintain or increase food production with a reduced availability of water. This can be achieved by understanding mechanisms for adaptation to water stress conditions and exploiting the existing variation in the crop and wild relatives. The specific objectives of this project include (a) to understand physiological mechanisms of adaptation to water stress and drought tolerance, and to improve water use (b) to assess the impact of water stress, rainfall variability and climatic change on yield, and other physiological parameters and develop a knowledge base about crop water productivity under different water stress and management practices and identify Quantitative Trait Loci (QTL) (c) to capture and identify naturally occurring variation for adaption to water stress conditions and identify genetic regions of interest associated with water stress tolerance and yield under stress by using trait gene correlations aiming at associations due to several years of recombination in potato germplasm (d) to prepare crop models from G×E information available on yield and physiological parameters from multi-year trials which will help predict better performing genotypes under prevailing climatic conditions and (e) to link the phenotypic parameters to candidate genes by using information from model plant studies and cereal crops.These objective will be achieved by developing knowledge and tools for breeding for Water Use Efficiency (WUE) which involves: physiological parameter measurements, eco-physiological approaches and agronomical practices in crop production and development of molecular marker resources to map QTL’s for environmentally sustainable traits."