Further Evidence of Epistasis in Single and Three‐Way Cross Yields of Maize (Zea mays L.)1

Six unselected lines from the variety ‘Midland’ ( Zea mays ) were compared in single‐ and three‐way crosses to provide estimates of the influence of epistasis on grain yield. Significant estimates of epistasis were obtained involving five of the six lines. In spite of the significance of the estimates, epistatic effects are not considered to be of major importance.