Abstract:
To develop synthetic varieties, not only the estimation of General Combining Ability
(GCA) for forage production is required but also the stability of
GCA
for parental
genotypes is necessary. Little is known about genetic analysis and selection for high
pr
oduction, combining ability, and stability in grasses. In this study, half
-
sib families
derived from the polycross of 25 smooth bromegrass genotypes were evaluated under 10
environments (combination of five years and two moisture environments, including no
n
-
stressed and drought stress conditions). Considerable variation for genetic and
Genotype×Environment (G×E) interaction was found among half
-
sib families. Low broad
sense heritability (27%) was found for forage yield indicating that selection based on an
index may be more useful for improvement of this trait in recurrent selection programs.
On the other hand, since the interactions of genetic by environment are significant,
selection of superior genotypes for development of synthetic varieties should be do
ne
based on multi
-
environments trails.
Keywords:
Additive effects,
Bromus inermis
, Drought stress, Polycross, Synthetic variety
