FATTY-ACID COMPOSITION OF OIL FROM ADAPTED, ELITE CORN BREEDING MATERIALS

The fatty acid composition of corn oil can be altered to meet consumer demands for ''healthful'' fats (i.e., lower saturates and higher monounsaturates). To this end, a survey of 418 corn hybrids and 98 corn inbreds grown in iowa was done to determine the fatty acid composition of readily-available, adapted, elite corn breeding materials. These materials are those used in commercial hybrid production. Eighty-seven hybrids grown in France (18 of which also were grown in iowa) were analyzed to determine environmental influence on fatty acid content. The parents of the hybrids and the inbreds were classified in one of four heterotic groups: Lancaster, Stiff Stalk, non-lancaster/non-Stiff Stalk, and Other. t-Tests and correlation analyses were performed with statistical significance accepted at a level of P less than or equal to 0.05. The findings showed a wide range of fatty acid profiles present in adapted, elite corn breeding materials with ranges for each fatty acid as follows. palmitic acid, 6.7-16.5%; palmitoleic acid, 0.0-1.2%; stearic acid, 0.7-6.6%; oleic acid, 16.2-43.8%; linoleic acid, 39.5-69.5%; linolenic acid, 0.0-3.7%; and arachidic acid, 0.0-1.0%. Small amounts of myristic acid, margaric acid, and gadoleic acid also were found. Three lines had total saturates of 9.1% or less. Thirty-six of the t-tests involving hybrids showed significant differences among heterotic groups. There were small but significant correlations among protein, starch and oil content and the amounts of several fatty acids. Results from the corn grown in France vs. iowa demonstrated a large environmental effect that overwhelmed the genetic differences among lines. This study shows that for some attributes, a breeding program involving adapted corn breeding materials might produce the desired oil. Other types of oil (such as high-oleic) would have to be produced in a different manner, for example, by a breeding program with exotic breeding materials.