TABLE 5

Summary of least-squares mean and effect estimates from ANOVA on ln(X + c)-transformed trait values

Group/effectTotal
productivity
Early
productivity
Late
productivity
wLongevity
A. Least-squares means
Unmutagenized background
    Control (00)5.244.543.96-0.282.56
    Treated (01)4.222.953.56-1.882.50
Mutagenized background
    Control (10)5.104.224.16-0.602.55
    Treated (11)3.852.493.33-2.422.51
B. Effect estimates (SE)
Additive effect, Aa1.157***1.909***0.2021.930***0.078
(0.248)(0.292)(0.252)(0.315)(0.049)
Interaction effect, Bb0.2300.1410.418*0.216-0.025
(0.225)(0.266)(0.226)(0.287)(0.042)
  • * P < 0.06, *** P < 0.0001.

  • a A represents the expected reduction in log-transformed trait values of double-mutagenized (11) lines if the mutations in the two mutagenesis treatments do not interact.

  • b Positive interaction effects indicate a greater reduction on the loaded background than on the unloaded background, i.e., synergistic epistasis.