Genotyping and Fatty Acid Composition Analysis in Segregating Peanut (Arachis hypogaea L.) Populations

Oleic acid (C18∶1), a monounsaturated omega-9 fatty acid, is an important seed quality trait in peanut (Arachis hypogaea L.) because it provides enhanced fatty acid composition, a beneficial effect on human health, improved flavor, and increased shelf life for stored food products by delaying rancidity. Consequently, an emphasis has been placed on breeding peanuts with high levels of oleic acid and low levels of linoleic acid (C18∶2), a polyunsaturated, omega-6 fatty acid. Therefore, crosses were prepared between high oleic and normal peanut lines to develop segregating F2 populations. Total fatty acid composition and the ahFAD2B genotype were determined in the parents and progeny. The oleic to linoleic (O/L) ratio varied from 0.85 to 30.30 in the F2 progeny. Comparing the mean oleic acid values from the three genotypic classes (Ol2Ol2, Ol2ol2, and ol2ol2) in each population confirmed that the means were significantly different. Statistical analysis demonstrated that oleic acid was negatively correlated with linoleic (C18∶2) and palmitic acid (C16∶0), but was positively correlated with gadoleic (C20∶1) and lignoceric (C24∶0) fatty acids. This suggests that modifier genes may influence fatty acid composition. Principally, integration of genotyping and phenotyping data from segregating populations provided valuable insights on the genetic factors controlling total fatty acid composition.