The genetic parameters controlling the expression of seed yield and some of
its components have been studied using generation mean analysis In three faba bean
crosses namely; C. 611148194 x Giza 3/6125,C. 811156194 x Giza 316125 and C.
9/1172/94 x Giza 3l6I25. Six populations of in each cross; P" P2, F" F2, BC, and BC2
were used in this concem, 10 estimate additive (CII), dominance (d) and (aa , (ad) and
(dd) types of eplsta15is according to Gamble's method (1962).
Significanf addmve gene effects were found for plant height (cm) In all
crosses, seed yield/plant in the second and third cross and 1QO.seed weigh (g) in the
third cross, indicting that selection after each generation of selfing would be effective
with such lraits. On the other hand, the dominance effects were significant and higher
in magnitude Ihan additive ones for pIal'll height (em) in the first and second cross,
number of branches/plant and 1 OO·seed weight (g) in the third cross and umber of
pods and seedslplant in the second ClOSS, Indicating the possibility to increasing yield
perfonnance via breeding procedure which emphasizes the dominance gene effects.
Significant (aa) and (dd) types of epistasis W618 found 10 be accompanied by the
significance of either F2 deviation (El) or bacJccross deviations (E2) for plant height
(em), number or branches/plant and 100-seed weight (g) in the third ClOSS.
Significant positive mid and better parental heterosis were found for plant
height (em) in first and second cross, number of pods/plant and 1OD-seed weigh! (g)
in all crosses, and seed yield/plant (g) in the second and third cross, due to
overdominance. Inbreeding depression values were signifICant for plant hei~ht (cm) in
first and second cross, and number of pods and seeds/plant and seed yiel1d/planl (g)
in the second and third ClOSS. Relatively high genetic gain upqn selection was found
to be aSSOCiated with moderate narrow-sense heritability (h2) values and relatively
high estimates 01 GCVO/O for number of pods and seeds and seed yield/pla~t (g) of the
third cross plants, Indicating the effective of selection for these traits of the oss.