GERMPLASM ENHANCEMENT OF MAIZE PROJECT (GEM)
Location: North Central Regional Plant Introduction Station, Ames, Iowa
Project Number: 3625-21000-050-00
Start Date: Feb 05, 2008
End Date: Feb 04, 2013
The long-term objectives of this project are to identify and incorporate useful maize genetic diversity to support sustainable productivity of the most important crop in the United States, as measured by acreage planted, farm gate value, product value and strategic importance. To accomplish this, we will: 1) manage and coordinate a multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, inbred line development, and information sharing focused on broadening the genetic base for U. S. maize; 2) evaluate maize germplasm with a broad spectrum of non-U.S. and mixed U.S./non-U.S. pedigrees for adaptation, yield, resistance to biotic and abiotic stresses, and key value-added traits; 3) breed and release genetically-enhanced populations and inbred lines, derived from non-U.S. and/or mixed U.S./non-U.S. germplasm sources, that are commercially-competitive and/or which contain key traditional or novel traits; and 4) develop innovative means of managing and transferring evaluation and breeding information to multiple project cooperators and germplasm users.
Extensive collaboration efforts on the part of 60 current cooperators from the private, public and international sectors are required to broaden the germplasm base in effective ways that provide germplasm of use for food, feed, fuel, and industrial applications by producers and end-users. The Coordinator serves as the liaison for collaborators and the Technical Steering Group (TSG), selects germplasm, facilitates germplasm acquisition and stakeholder interactions, arranges for in-kind-support, information sharing, and technology transfer.
The Ames location will develop germplasm derived from 50% and 25% exotic breeding crosses developed by crossing tropical and temperate racial accessions with adapted, elite proprietary Corn Belt lines. Approximately 1,500 -1,600 S2 top crosses will be made and evaluated annually in yield trials, disease nurseries, and for value-added traits such as ethanol, protein, oil, and starch. Germplasm will be further evaluated by a network of cooperators with expertise, facilities, and favorable selection environments for the traits of interest. Important traits include mycotoxin resistance, abiotic stress tolerance, and insect resistance. Germplasm lines will be released to cooperators and selected lines registered and publicly released. Released lines will be maintained by the National Plant Germplasm System's maize curator.
An effort will be made to develop lines derived from approximately 250 races of maize to broadly represent the allelic diversity of the maize races. Initial crosses of racial accessions with expired PVP lines or other public lines are made in winter nurseries, and one backcross to the adapted line (BC1). The resulting BC1 generation will be used for selecting lines in Midwest nurseries in order to release a unique set of (F5 generation) adapted, racial derivative lines for research and discovery applications. Technologies and methodologies can be utilized such as SNP or SSR markers for genomic profiling and association analysis that offer potential to translate genomic knowledge to germplasm enhancement and utilization applications. Genotypes will be screened in selected environments to maximize selection for priority agronomic, biotic and abiotic stress, reduced mycotoxin, and value-added traits.