Inheritance of Fatty Acid Content in Peanut Oil1

Abstract

Abstract The stability or shelf-life of peanut (Arachis hypogaea L.) oil is related to the fatty acid content of the oil, with the major factor being the ratio of oleic (C18:1) to linoleic (C18:2) acid (O/L ratio). To obtain information needed for development of cultivars with improved oil quality, eight parents representing a range in oleic and linoleic content were crossed in diallel. Individual F1 seeds (F1 embryos) from the greenhouse and F2 bulk seed from the 56 crosses grown in the field were analyzed to determine levels of the eight major fatty acids. General combining ability (GCA) was consistently more important than specific combining ability (SCA) in both generations, suggesting that additive effects are important in the inheritance of fatty acid composition. Maternal effects were significant in the F1 but dissipated in the F2; thus the differences in the environment provided by the maternal parent was more critical to oil composition than heritable extranuclear factors. Reciprocal effects were significant in both generations suggesting an interaction between nuclear and extranuclear factors. Correlations between GCA effects and self means for O/L ratio were nonsignificant. Since no significant correlations were found between percent oil and any of the fatty acids or related variables, selection for improved fatty acid composition should not affect the oil content of seed. Of the lines studied, NC 7, NC-Fla 14, and 73–30 should be used as parents in a breeding program for oil quality.