Six inbred lines of corn and their F1’s, F2’s, and backcrosses were tested at two locations in each of 2 years. The population means obtained were used to estimate additive, dominance, additive × additive, additive × dominance, and dominance × dominance gene effects for six quantitative attributes.Variance components of cross × environment interactions indicated the presence of major interactions of gene effects with environments. The cross × year interactions were of major importance but the cross × location interactions were of minor importance. Additive gene effects appeared to be the most constant over environments followed by additive × dominance gene effects. The remaining types of gene effects indicated very little stability over environments for most of the attributes studied. Estimates of gene effects were most constant over environments for ear diameter in corn while yield, plant height, and seed weight showed little or no stability of the estimates of the gene effects.
Biplot Analysis of Line × Tester Data of Maize (Zea mays L.) Inbred Lines under Stress and Nonstress Environments
