A half diallel set of six genetically diverse lines of faba
beans, was evaluated for heterosia, general and specific combining
ability (GCA and SCA). Results showed significant negative mid-
parent. heterosis for flowering date (FD), maturity date (MD) and
mattrity period (MP). Ten hybrids expressed significant positive
. . mid—parent heterosis and nine hybrids expressed significant
better—parent heterosis for seed yield/plant.
GCA and SCA were significant for all traits with the excep
tiُn of the number of branches/plant.
- -Values largely exceeding unity for GCA/SCA ratio were ob
tained indicating the importance of additive and additive x addi
tive ‘gene action in the expression of the traits. Significant addi
tive component (D ), dominance component (h1) and overall.
heterozygous dominance were detected for all traits.High herit
ability values were obtained for (MD). (MP), number of seeds/pod.
and 100—seed weight. Moderate heritability values were obtained for
seed yield/plant and number, of branches/plant, - while low
heritability values were obtained for (FD), plant height and ntimbe
of pods/plant.
Correlations of parental means and their0 orde,r of dom1.ndzlce
show that small number of seeds/pod was dominant over large.riumber.
Increaser genes were dominant over decreasers for (MD),(MP)’ and
lOO—eed weight. And low seed yield/plant was dominant over high
yield. Breeding methods to handle the resulting material were postulated.
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