PEDIGREE DIVERSITY WITHIN THE LANCASTER SURECROP HETEROTIC GROUP OF MAIZE

Maize (Zea mays L.) breeders commonly classify inbred lines into heterotic groups based on pedigree information and/or combining ability. These heterotic groups influence how germplasm is used, and have increased the efficiency of breeding programs. The most widely recognized and exploited heterotic pattern in the U.S. Corn Belt is that of Reid Yellow Dent by Lancaster Surecrop. Pedigree information was used to examine the diversity present in 37 publicly developed inbreds of the Lancaster Surecrop heterotic group, and to investigate the evolution to its present state. All of the Lancaster Surecrop germ-plasm in the publicly developed inbreds included in the modern Lancaster Surecrop heterotic group was derived from two inbreds, Oh40B and C103. Furthermore, the amount of true Lancaster Surecrop germplasm is 50% or less in 36 of these inbreds, with >20 non-Lancaster Surecrop sources contributing germplasm to this heterotic group. The Lancaster Surecrop heterotic group has been modified considerably, with a reduction in Lancaster Surecrop germplasm and an increase in non-Lancaster Surecrop germplasm including Reid Yellow Dent.