Genetic Characterization of the North Carolina State University Maize Lines

• Published in: Crop science 2016-01, Vol.56 (1), p.259-275
• Main Authors: Nelson, P.T., Krakowsky, M.D., Coles, N.D., Holland, J.B., Bubeck, D.M., Smith, J.S.C., Goodman, M.M.
• Format: Article
• Language: English
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci2015.09.0532

ABSTRACT Since 1980, 150 North Carolina State University (NCSU) maize (Zea mays L.) inbreds have been developed and released on the basis of superior performance for topcross yield and other traits of agronomic importance. During this time, there has been great emphasis placed on breeding with exotic germplasm, with 86 NCSU inbreds having at least 50% exotic parentage and 40 of those having all‐tropical parentage. Maize germplasm released by NCSU represents a potentially useful resource for increasing maize diversity and performance in the United States. The objectives of this study were to characterize the genetic relationships among inbreds released from this unique breeding program and to compare them genetically with inbreds from other public and private breeding programs. The NCSU maize inbreds can be classified into five germplasm pools: Lancaster, Temperate‐adapted all tropical (TAAT), Lancaster × Tropical, Stiff Stalk, and Southern non‐Stiff Stalk; detailed analysis of pedigree records and molecular marker genotypes reveals additional substructure within each of these pools. There is general agreement among the four cluster analyses performed, three using single nucleotide polymorphism (SNP) data and one using pedigree‐derived coefficients of coancestry. We introduce a novel application of Procrustes analysis to identify disagreements between pedigree and marker similarities. The NCSU maize breeding germplasm includes diverse genetic backgrounds, as evidenced by the number of unique alleles compared with publically available inbreds from both public and off‐protection, private‐sector sources.