Evaluation location: Illinois, United States
Descriptive characteristics, agronomic performance, and seed composition data of soybean (Glycine max (L.) Merr.) germplasm were evaluated on accessions initially classified in maturity groups I through IV in the range from PI 578371 to PI 612761, plus some accessions that were omitted from earlier publications. Also included were cultivars in the same maturity groups, developed at public institutions in the United States and Canada, and released by 2001. The accessions were evaluated in 2001 and 2002 in Urbana, Illinois (Lat. 40o 00' N). Planting dates were May 4, 2001 and May 27, 2002. Plots were 4 m long with 4 rows 76 cm apart. They were trimmed to 2.4 m after maturity and the middle two rows harvested. Accessions initially classified as maturity group I were stunted by herbicide damage and were not harvested in 2002. Seed composition was analyzed at the USDA Northern Center for Agricultural Utilization Research in Peoria, IL. Fatty acid composition was obtained by gas liquid chromatography of the methyl esters (Christie 1989, Bannon et al. 1982). Oil and protein for samples with yellow seed coats was analyzed using the near infrared method for whole-grain analysis (AACC Method 39-21). Protein concentrations for samples with colored or heavily mottled seed coats were obtained using the improved Kjeldahl method (AACC Method 46-16) and oil by the Butt Extraction method (AOCS Official Method Ac 3-44).