Maximizing dry milling efficiency: Selection for large-grit yield in maize

Corn is an important human dietary component; in 2009, 1.48 percent of the total U.S. corn harvest, or 193.66 million bushels of corn grain, were used to produce cereals and other food products. The dry milling process separates the embryo and seed coat, resulting in various size categories of endosperm, the largest of which is "large grits."

A study was conducted to understand the genetics influencing large-grit yield. Hybrids representing parentage in female and male germplasm pools used in current U.S. commercial corn hybrids were evaluated for agronomic performance as well as dry milling yield. Since the envi- ronment significantly influences expression of grain traits, 3 years of data are being collected. Differences among hy- brids for both agronomic performance and large-grit yield have been observed. However, preliminary data indicate a negative correlation (r2 = -0.25) between grain yield (bu/A) and large-grit yield. Outcomes of this work will include breeding strategies to select for hybrids that maximize both large-grit yields and grain yields as well as ways to efficiently estimate dry milling efficiency.