Abstract:
The choice of an efficient breeding procedure depends to a large extent on knowledge of
the genetic system controlling the character to be selected. The objective of this study was
to determine genetic parameters for yield and other traits including some of the yield
components under three planting densities, using analysis of generation means (P1, P2, F1,
F2, BC1 and BC2) derived from crosses of B73 with Mo17 and K74/1 inbred lines of corn.
Analysis of variance reinforced the hypothesis that interaction of plant density on generation
means depends on evaluating genotypes and the kind of trait. Generation mean
analysis suggested that both additive and dominance effects were important for most of
the traits evaluated in this study, but dominance had a more pronounced effect. Epistasis
affected the expression of nine traits in both crosses at three planting densities. Expression
of epistasis and genetic parameters differed in the two crosses and were influenced by
plant density. Plant densities interacted more strongly with epistasis gene action than with
additive or dominance gene action in both crosses
