Wild potatoes (Solanum section Petota) are taxonomically difficult. They have tremendous morphological and physiological variation, and taxonomic treatments have shown much disagreement regarding species boundaries, number of series (a taxonomic group uniting groups in interrelated species), affiliation of species to series, and hypothesis of hybridization. Interest in the use of low-copy nuclear genes for phylogenetic analyses of plants has grown rapidly, because in the past much molecular systematic work has used chloroplast gene sequences. Corroborative data from nuclear gene sequences are needed for comparison. Low-copy genes are subject to different evolutionary processes than are plastid genes or highly repetitive nuclear markers (such as ITS), and they provide a valuable source of independent phylogenetic evidence. The purpose of my research is to explore the use of low or single copy nuclear genes for the taxonomy of wild potatoes, to provide a global analysis of series relationships. I am designing primers and will test four single copy genes using cloning and sequencing. Currently I am working on nitrate reductase, a single copy gene in potato. I am sequencing intron 1 (about 74 bp in tomato), intron 2 (847 bp), and intron 3 (436 bp). In total, with the exonic region, the NIA region I am examining contains includes 2400 bp.