The protein and oil composition of corn grain is a major factor affecting grain feeding value. Although the grain market does not include this factor in price determination, growers who feed livestock may use this information to reduce feed costs and optimize diets. Hybrid genetics significantly affect the protein and oil content of corn grain. For feed, protein content is of primary interest, whereas for processing uses, oil content is of interest. Corn grain is typically 8 percent protein and 3.6 percent oil (on a 15.5 percent moisture basis).
Although significant differences among hybrids for oil and protein are evident in under certain testing conditions, the Ohio Corn Performance Test has indicated that protein and oil levels vary considerably from test to test (Table 4-8). Some normal dent corn hybrids produced primarily for grain exhibit elevated protein and oil levels. Environmental conditions (temperatures, rainfall) and cultural practices (nitrogen fertility, plant population) can influence grain composition, especially grain protein. Additional information on hybrids developed for special grain com- position characteristics is in the Specialty Corns section in this chapter.
Table 4-8: Average Protein and Oil Content of Corn Grain (at 15.5 Percent Grain Moisture), Ohio Corn Performance Test, 2001-2003.
Early Maturity Test |
Full Season Test |
||||
Year |
Region |
Protein |
Oil |
Protein |
Oil |
|
|
------%------ |
------%------ |
||
2001 |
SW |
7.5 |
3.3 |
7.4 |
3.5 |
|
NW |
8.5 |
3.7 |
8.5 |
3.9 |
|
NE |
8.9 |
3.8 |
8.4 |
3.8 |
2002 |
SW |
8.5 |
4.0 |
8.5 |
4.1 |
|
NW |
8.9 |
4.3 |
9.1 |
4.4 |
|
NE |
8.1 |
3.9 |
8.4 |
4.1 |
2003 |
SW |
8.5 |
3.8 |
8.4 |
3.8 |
|
NW |
8.0 |
3.7 |
8.0 |
3.8 |
|
NE |
8.3 |
3.6 |
7.9 |
3.7 |
Source: 2001-2003 OSU Corn Performance Test.