Estimates of Epistasis for Diverse Peanut Cultivars^1,2

Progeny from a six-parent half-diallel of diverse peanut (Arachis hypogaea L.) cultivars were evaluated for the F₁ through F₅ generations for presence of epistatic effects. Significant variability attributable to specific combining ability (SCA) persisted over generations for yield and other seed characters. Epistasis was indicated since dominance could account for little of the variance due to SCA in the F₅ generation. Estimates of dominance and epistatic variance components were obtained using an iterative weighted least squares procedure. For all characters measured, estimates of epistatic variance were larger than those of dominance variance. It was concluded that considerable epistatic variance may exist in populations derived from crosses of diverse peanut lines.