The establishment of wine grape production systems in Nevada fulfills the need for an alternative crop with high water use efficiency that also can be converted to a value-added product with significant economic impact on the state economy. The production efficiency of wine grapes could potentially be hampered by abiotic stresses like drought, freezing temperatures, and soil salinization. Paradoxically, several studies have shown that grapes from drought-stressed vines can result in the production of a superior quality wine with highly desirable aroma, flavor and color characteristics. However, the molecular and biochemical basis of stress tolerance and wine quality improvements are poorly understood due to the complexity of abiotic stress responses. We will use oligonucleotide-based microarrays to assess changes in gene expression patterns following abiotic stress in order to improve our understanding of the molecular genetic basis of abiotic stress responses and wine quality. We also will use genomic DNA-based microarrays to define the hierarchical relationship between key transcriptional activation factors active under abiotic stress conditions and the genes whose expression they control. The outcome of this research will lead to improved wine grape production efficiency in stressful climates and give us a better understanding of the factors that contribute to improved wine quality.