Gilbert, Erin2018-02-132018-02-132017-09https://hdl.handle.net/11299/193416University of Minnesota M.S. thesis.September 2017. Major: Applied Plant Sciences. Advisor: Aaron Lorenz. 1 computer file (PDF); xvii, 187 pages + 3 supplementary files.The USDA Soybean Isoline Collection was analyzed by combining historical phenotype and pedigree data with recently collected and publicly released SoySNP50K data. This collection was created and released over the course of nearly 20 years in order to isolate intervals associated with contemporarily significant qualitative traits (Bernard, 1991). With the release of the SoySNP50K genotyping array and the subsequent genotyping of the USDA germplasm, it is possible to bring higher resolution analysis of this historical collection. Publically available genotyping data for 277 near isogenic lines (NILs) and their associated parents were downloaded from Soybase.org. These data were combined with pedigree and phenotyping records to characterize this population in terms of pedigree type and content, parent/offspring identity, and donor parent introgressions. Here we present results regarding the characterization of this collection in terms of content and NIL isogenicity, and also use the NIL data for trait mapping. Forty-one traits were mapped here, with 33 improving upon previous mapping data and 8 newly mapped traits.enThesis or Dissertation