Minnesota Corn Breeding History: Department of Agronomy & Plant Genetics Centennial

A century of corn ( Zea mays L.) breeding at Agronomy & Plant Genetics, University of Minnesota, developed Minnesota 13 cultivar (Minn13) that enlarged the U.S. Corn Belt and also developed 273 corn inbreds. Minn13 was widely grown in 15 northern and higher elevation states for 40 yr before hybrid corn. Minnesota inbreds were used in 30.6% of the seed for the 1975 U.S. corn crop: Minnesota A632 15.2%, A634 7.8%, A619 4.2%, W117 (1/2 Minn13) 1.8%, A635 0.9%, A554 0.6%, and A654 0.1%. Our main objective is to measure the contribution of Minnesota corn breeding to today's corn. We define today's corn as the 305 proprietary corn inbred lines registered by U.S. Plant Variety Protection or utility patent 2004 to 2008. Minnesota developed corn inbreds contributing most to today's corn are C49 (A9), A509, A556, B164, and A237. These corn inbreds were sources of earliness that formed the Pioneer Early Iodents (PEI) at Mankato, MN in the early 1960s. They average 1.1% of the genes and 137 (45%) of the descendents among today's corn. The Minn13 inbred line descendents contributing most to today's corn are DeKalb/Monsanto's (DKM) 3IIH6, PEI's PH207, PHG3BD2, Ohio Oh43, and Holden/Monsanto's (HFM) LH82. Minn13 descendents have maintained about 4% genetic contribution 1984 to 2008. Clustering pedigree based genetic distance of Minn13 derived progeny in today's corn showed three major pedigree groups: HFM's LH82, PEI, and DKM's Iodent. The latter two are Early Iodent germplasm.