2006 Annual Report 4d.Progress report. This report serves to document research conducted under a specific cooperative agreement between ARS and North Carolina State University. Additional details of research can be found in the report of the parent CRIS project 3625-21000-047-00D, "Germplasm Enhancement of Maize Project (GEM)". This project relates to the primary objectives of the parent project which include coordination and conducting the GEM Project for the southern region with focus on 50% tropical derivation. In 2006, 83 entries were advanced from first year to second year trials, and 58 entries advanced from second to third year trials. Approximately 18,439 plots were coordinated through Raleigh, of which 10,517 were planted at NC State locations. This is a significant increase over 2005 trial activity (12,224 plots of which 4,013 were planted at NC State locations). Approximately, 1,500 nursery, and 1,225 isolation rows were planted in 2006. Breeding cross evaluation for yield continues in 2006 as in the past two years. Data from these studies revealed a great spread in yield potential, and influenced our decisions for 2006 nursery material for development. A report on this research was provided at the Annual GEM Cooperator's meeting in December, 2005, and published in a 2006 edition of Maydica as an invited article. About 200 nursery rows were planted to the Allelic Diversity study which includes accessions outside the core GEM breeding material, and not likely used in most breeding organizations. Approximately half of the allelic diversity material includes new F1's from 25 accessions made by Syngenta as part of the in kind support effort to GEM. The remaining material is F3 produced in the NC State winter nursery. Progeny from both sets will be sent to winter nursery for further inbreeding. Collaborative work with other USDA-ARS and university scientists includes molecular marker work for disease resistance with the USDA-ARS in Raleigh, NC, and NC State University. Other research includes racial classification using molecular markers in collaboration with the USDA-ARS in Ithaca, NY, and the University of Wisconsin.