120), but since the value is low, indirect selection
for ED may fail to provide satisfactory gains in FW, and is not the best selection strategy for larger fruits.
This result allowed inferring that genotypes with greatest grain yield may be obtained from the indirect selection
of genotypes with higher number of seeds per plant and increased grain weight.
In general, the indirect selection
among primary components of yield (MY) seems to be a good strategy for genetic progress in the most important primary character, since most of the indirect effects are positive.
Genetic gains through direct and indirect selection
for fruit yield (ton [ha.
The direct selection response (RY) of each target trait to single trait direct selection of the target trait (Y), the indirect selection
response (CRY) of each target trait to the selection of indicator traits (X), and the ratio of the indirect selection
response to direct selection response (CRY/RY) were calculated by the following equations (Falconer, 1989).
Selection for a trait in plant breeding can be held in two ways; direct selection by measuring this trait as a classical method or indirect selection
considering with other traits.
As with evolutionary change in female preference, there is indirect selection
arising from the covariance between genes for the handicap and genes for high viability ([B.
Consequently, the evolution of floral displays may often be influenced by herbivores, while the evolution of chemical defenses may often be influenced by indirect selection
imposed by pollinators.
Genetic correlations between traits can result in differentiation with respect to traits that are not related to fitness if there is sufficient indirect selection
(Darwin 1859, Gould and Lewontin 1979, Lande and Arnold 1983).
From the average squares obtained by the analysis of variance, the components of variance associated to the genetic and environmental effects of the statistical models and the selection gains were estimated using the direct and indirect selection
method, according to Cruz et al.
may facilitate and accelerate the selection of promising genotypes in feijoa genetic breeding, which requires the study of correlations between traits.
So due to less impression of direct selection for yield, more efforts should be over indirect selection
for yield components (changing yield through yield components).