Submitted to: Plant and Animal Genome Conference
Publication Type: Abstract Only
Publication Acceptance Date: 12/18/2017
Publication Date: 1/15/2018
Citation: Gardner, C.A., Krakowsky, M.D., Peters, D.W. 2018. Germplasm Enhancement of Maize (GEM) - 24 Years of Public-Private Sector Collaboration to Increase Maize Genetic Diversity [abstract]. Plant and Animal Genome Conference. Abstract # W527.
Technical Abstract: The Germplasm Enhancement of Maize (GEM) Project is a mission-oriented, cooperative research effort of the USDA/ARS, land grant universities, private industry, and international agricultural research centers to broaden the germplasm base of maize cultivated within the US. The Raleigh location of the GEM Project is focused on identifying new exotic sources of maize germplasm and on developing 50% exotic/50% temperate germplasm, while the Ames location focuses on developing 25% exotic/75% temperate germplasm with high yield potential and resistance to common foliar, stalk and ear diseases which can be incorporated directly into commercial maize breeding programs. This is challenging because tropical maize is photoperiod sensitive and lacks adaptation to temperate conditions. While exotic germplasm can be defined as any germplasm that has not been sampled in a breeding program, the GEM project uses the term to cover landraces and improved germplasm from tropical and subtropical origins. The environmental conditions and geographical latitude of the Raleigh location make it feasible to work with breeding material that contains a higher percentage of exotic germplasm than is usually practical at Midwestern locations such as Ames, IA, and this enables the transfer of more genetic diversity into prebreeding germplasm. University collaborators focus on specific traits or areas of interest, and have released improved germplasm for biotic and abiotic stress resistance, for novel starch properties, and to understand the nature of diversity. Graduate students in US public universities have gained experience with introgression breeding and maize genetic resources, critical training to provide for continued crop improvement. Private sector collaborators provide proprietary germplasm and nursery and testing resources to characterize performance for a wide variety of traits. In addition to developing germplasm for use in maize breeding programs, the GEM project also develops new resources that allow the introgression of useful alleles from agronomically inferior exotic sources. This is known as the Allelic Diversity (AD) project, and involves crossing and backcrossing accessions from all of the races of maize to two formerly proprietary temperate inbreds to develop a panel of lines that represent the diversity of maize. This panel can be used to screen for alleles of interest that would otherwise be unavailable to maize researchers. To date, GEM project participants have released about 300 conventionally derived, diverse lines. Additionally, more than 200 double haploid lines have been released as part of the AD project.