Tuesday, November 14, 2006

Maize races and traits identified from the GEM Project.

Michael Blanco1, Candice Gardner2, Wilfredo Salhuana3, and Nuo Shen1. (1) USDA-ARS Plant Introduction Station, Ames, IA 50011, (2) USDA-ARS, USDA-ARS Iowa State Univ., G212 Agronomy Hall, Ames, IA 50011, (3) Retired Pioneer Fellow, and GEM TSG Chairman, 6204 SW 146th Ct., 6204 SW 146th Ct., Miami, FL 33183

The Germplasm Enhancement of Maize Project (GEM) is a cooperative effort of the USDA-ARS, land grant universities, private industry, international, and non-governmental organizations to broaden the germplasm base of maize.  The project is administered through the USDA-ARS Plant Introduction Research Unit in Ames, IA, and the Plant Science Research Unit in Raleigh, NC.  The Latin American Maize Project (LAMP) preceded the GEM Project; it identified and provided the valuable primary source material of exotic germplasm used by GEM.  During the past 5 years, GEM released 135 lines from S3 to S6 generation, representing 20 races of maize.  Some of the more important traits derived from GEM breeding crosses include abiotic stress resistance from Dentado Blanco Rugoso (ARZM 01150), Fusarium ear rot, and anthracnose stalk rot from US mixed racial sources FS8A(S), and FS8B(T) respectively, and Corn Root Worm resistance from the accession URZM 13085, representing the Cateto Sulino race.  Germplasm derived from 50% tropical breeding crosses have been excellent sources of resistance to Fusarium, Gray Leafspot, and southern rust.  Value added traits include high protein, and silage quality identified in Cuba 117, and Cuba 164, (races Argentino and mixed Criollo respectively).  The Tuson racial accession, GUAT209, was found to be a source of modifiers for high amylose.  Cristalino Colorado accessions ARZM 17026, and ARZM 17056 are good sources of silage quality, and starch digestibility respectively.  These accessions are publicly available, and should provide useful sources of diversity for enhancing and broadening the germplasm base.

Handout (.pdf format, 123.0 kb)