Types of gene effects governing the inheritance of oleic and linoleic acids in peanut (Arachis hypogaea L.)

Abstract

Oleic and linoleic acids are major fatty acids in peanut determining the quality and shelf-life of peanut products. A better understanding on the inheritance of these characters is an important for high-oleic breeding programs. The objective of this research was to determine the gene actions for oleic acid, linoleic acid, the ratio of oleic to linoleic acids (O/L ratio) and percentage oil (% oil) in peanut. Georgia-02C, SunOleic 97R (high-oleic genotypes) and KKU 1 (low-oleic genotypes) were used as parents to generate P₁, P₂, F₂, F₃, BC₁₁S and BC₁₂S. The entries were planted in a randomized complete block design with four replications in the rainy season (2008) and the dry season (2008/2009). Gas liquid chromatography (GLC) was used to analyze fatty acid compositions. The data were used in generation means analysis to understand gene effects. The differences in season, generation and generation X season interactions were significant for oleic acid in the crosses Georgia-02C X KKU 1 and SunOleic 97R X KKU 1. Additive, dominance and epistasis gene effects were significant for oleic acid, linoleic acid, O/L ratio and % oil. Initial selection can be carried out in early segregating population, and final selection in late generations.

Keywords: Breeding, gene actions, generation mean analysis, groundnut, oil quality