GENE EFFECTS IN CORN (ZEA MAYS L.): II. RELATIVE IMPORTANCE OF GENE EFFECTS FOR PLANT HEIGHT AND CERTAIN COMPONENT ATTRIBUTES OF YIELD

Abstract

Estimates of mean effects, additive, dominance, additive × additive, additive × dominance, and dominance × dominance gene effects were obtained for 15 crosses from 6 inbred lines of corn for each of the following attributes: plant height, kernel row number, ear length, ear diameter, and seed weight.All the gene effects were found to contribute to inheritance of the attributes in the crosses studied. However, not all gene effects are present in all crosses. Mean effects were the most important contributors to the inheritance of the attributes. Of the gene effects, the dominance gene effects were the most important contributors to the inheritance of the attributes except for kernel row number. Additive, dominance and epistatic gene effects appear to contribute more or less equally to the inheritance of kernel row number. Additive gene effects were more important for these attributes than for yield. They were relatively more important for kernel row number, ear diameter, and seed weight than for plant height and ear length.Epistatic gene effects were relatively more important than additive gene effects but less important than dominance gene effects for the material studied. For the attributes studied the additive × dominance and dominance × dominance gene effects were somewhat more important contributors to inheritance than the additive × additive effects.