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ARS Home » Southeast Area » Raleigh, North Carolina » Plant Science Research » Research » Research Project #424642

Research Project: Broadening the Genetic Base of U.S. Maize with Genes from Unadapted Germplasm

Location: Plant Science Research

Project Number: 6070-21000-030-00-D
Project Type: In-House Appropriated

Start Date: May 9, 2013
End Date: May 8, 2018

1. Manage and coordinate the Southeastern U.S. component of an ongoing, multi-site, cooperative program of maize germplasm evaluation, genetic enhancement, germplasm line development, and information sharing which seeks to broaden the genetic base for U.S. maize. 2. Evaluate a wide diversity of unadapted sub-tropical and tropical maize germplasm for adaptation, yield, and disease resistance. 3. Breed and release genetically-enhanced maize populations and lines, derived from unadapted sub-tropical and tropical maize germplasm, that can contribute to new commercial hybrids, more diverse genetic resistance to biotic stresses, superior yield and other valuable new traits. 3A. Breed and release genetically-enhanced maize lines, derived from unadapted sub-tropical and tropical maize germplasm, that can contribute diverse and valuable new traits to commercial and public breeding programs. 3B. Develop and release a novel set of “adapted” maize races resulting from the allelic diversity (AD) program as tools for gene discovery and genomic research.

Exotic sources used for developing new breeding populations will be selected in cooperation with the Ames GEM (Germplasm Enhancement of Maize) coordinator and the GEM Technical Steering Group. Private company cooperators will make the initial crosses between commercial and exotic stocks, and each cooperator has agreed to conduct a specific set of evaluations (e.g. yield trials, abiotic or biotic stress, or breeding cross evaluations) along with evaluations conducted in North Carolina by the Raleigh GEM coordinator. New exotic germplasm sources will be evaluated in testcrosses and then crossed to either proprietary inbreds or formerly proprietary (ex-PVP) inbreds to develop new breeding crosses for further evaluation. These breeding crosses will then be self-pollinated for two generations in disease nurseries to enhance selection of the most promising genotypes, which will be testcrossed and evaluated in yield and disease trials for three seasons. In addition, less agronomically promising sources of exotic germplasm will be backcrossed to elite temperate inbred lines and inbred to create a set of 25% exotic/75% temperate lines that can be used for allele mining and gene discovery.