Research Abstracts Online
January 2010 - March 2011
University of Minnesota Twin Cities
College of Food, Agricultural, and Natural Resource Sciences
of Agronomy and Plant Genetics
PI: Rex N. Bernardo
Genome-Wide Selection to Introgress Exotic Dwarf-Corn Germplasm Into U.S. Corn Belt Germplasm
Corn (Zea mays L.) hybrids have progressively become higher yielding, shorter, and better adapted to high plant-population densities. A dwarf plant stature may lead to (i) higher corn productivity at very high plant-population densities, (ii) expanded areas for production, and (iii) benefits in crop rotation, weed management, and control of soil erosion. In this research, cheap and abundant single nucleotide polymorphism (SNP) markers are used to introgress useful traits from dwarf corn into adapted corn inbreds. Genomewide selection is used in an attempt to rapidly improve two dwarf x non-dwarf corn populations. The populations have been genotyped for random SNP markers and phenotyped for grain yield and agronomic traits. Genotypic value for multiple traits will be predicted from all markers. The populations will then be subjected to multiple cycles of marker-based selection in a greenhouse. This procedure increases the genetic gain per unit time by allowing four generations of marker-based selection per year.
A practical outcome of this research is corn germplasm that combines high grain yield from adapted corn and reduced stature and adaptability to high plant population densities from dwarf corn. A scientific outcome is the validation of a marker-assisted selection method that may eventually allow the rapid introgression of useful traits from other kinds of diverse, exotic germplasm into U.S. corn.
Emily Combs, Graduate Student