Increasing Genetic Diversity in Public- and Private-Sector Maize Breeding World-Wide
The importance of access and utilization of genetic plant resources for improvement of modern cultivars is widely recognized. The maize seed industry has struggled to maintain long term germplasm introgression efforts to incorporate genetic diversity into their elite breeding pools because of lack of adaptation and undesirable agronomic traits associated with exotic maize germplasm, the time required to extract valuable material, and the rapid nature of breeding cycles in commercial programs.
In the early nineties, at the conclusion of the Latin American Maize Project (LAMP) project, the US participants pursued discussions of how materials identified with good potential could actually be utilized to broaden the diversity of U.S. maize. The Germplasm Enhancement of Maize (GEM) Project resulted from these discussions and recognition by the U.S. Congress of the urgent need to broaden and enhance the maize germplasm base. After 22 years, nearly 60 entities representing the private, public, and non-governmental organizations (NGO) in the US and twelve other countries now collaborate to achieve GEM objectives.
More than 301 varieties have been released from programs based in Ames, IA, Raleigh, NC, and from university researchers, from ~ 40 maize races or tropical hybrids and inbreds. Also, about 200 doubled haploid lines from nearly 60 exotic landraces have been released to serve as rich resources for exploration of allelic diversity and novel traits, and to provide valuable germplasm for maize research by graduate students in plant breeding and genetics. New germplasm and knowledge derived will support efforts to meet the every increasing challenges to sustainable production.
Aiming to keep pace with a constantly changing environment in the seed industry, recently the GEM program reviewed its entire breeding methodology to decrease cycle time, access germplasm not previously available, and increase the quality of the germplasm to be released.
Public-Private-Partnership efforts are essential to provide useful germplasm for introgression, to perform breeding and testing activities, to evaluate germplasm for abiotic and biotic stress resistance (especially for diseases and pests not yet endemic to the U.S.), for yield, agronomic and grain quality traits, and to conduct research to identify useful haplotypes from exotic donor genomes.