Wisconsin farmers lead the nation in silage production, producing more than 10 million tons per year. Research at the University of Wisconsin-Madison aims to improve the nutritional value of that cow chow. Jim Coors, a corn breeder in the College of Agricultural and Life Sciences, has identified exotic corn inbreds that have high nutritional values as silage. One of these inbred families, from Uruguay, could significantly increase the nutritional quality above levels now available in commercial hybrids.

For three years, Coors evaluated exotic corn varieties through the USDA”s Germplasm Enhancement of Maize project. The project began in the late 1980s with 12,000 corn germplasms from Latin America and the goal of adding genetic diversity to the U.S. corn crop to help improve disease and insect resistance, yields, and other traits.

By 1995 breeders narrowed the list to 286 elite populations for enhancement, and identified 30 early maturing populations that Coors began to evaluate for their potential as silage. Other projects around the nation are evaluating other GEM germplasms for improved starch quality, grain yield, and drought, insect, and disease resistance.

By selecting for high digestibility, high protein and low fiber, Coors narrowed the list to four for breeding advancement and evaluation for silage. In 1997, through inbreeding, Coors developed 217 first-generation inbred lines and found the cream of the crop that will be used in testing for commercial silage hybrids.

“Twenty families from Uruguay, Chile, Argentina and the U.S. will be used to make parental lines and crossed with other commercial inbreds for further testing throughout the North Central region,” says Coors. “The results of this research should be available to industry breeders within the next two to three years.”

One of these new inbred families, from Uruguay, looks especially promising. In 1997, this family, UR13085:N0204, had a stover composition of 66 percent neutral detergent fiber, 77 percent dry matter digestibility, and 65 percent cell wall digestibility. For comparison, typical corn silage hybrids in Wisconsin had a stover composition of 68 percent NDF, 72 percent DMD, and 59 percent CWD.

“By using these exotic inbreds to develop commercial hybrids,” Coors says “we may be able to increase milk production by several pounds per day for each dairy cow.”

Coors” work to improve silage extends beyond the exotic germplasm project and is the only public corn breeding project in the nation that focuses on improving traits for silage. For more information, a September 1996 CALS press release on corn breeding for silage is on the WorldWideWeb at https://webhosting.cals.wisc.edu/media/news/09_96/996coorscorn.html