H ETEROSIS, potence ratio, inbreeding depression, gene action,
genetic coefficient of variation, heritability and predicted genetic
gain for earliness, number of branches and plant height in the two
crosses; Giza 2 X Introduction 54 and Giza ، X Introduction 44 were
studied. Six populations in each cross, namely, Pj, P2, F1, F2, Bcj,
and Bc2 were used.
Highly significant positive heterosis were detected for; fruiting
period, first flowering node and first fruiting node in the first cross,
number of branches per plant in the second cross, and plant height in
both crosses. Highly significant negative heterosis were detected for;
fruiting period, first flowering node and first fruiting node in the first
cross, number of branches per plant in the second cross, and plant
height in both crosses. Highly significant negative heterosis were
detected far; flowering date in both crosses, maturity date and first
flowering node in the second cross. Insignificant heterosis were ob
tained for remaining cases.
Over dominance, towards the higher parent was found for; first
fruiting node, number of branches per plant and plant height in both
crosses. However, over dominance towards the lower parent was
detected for flowering time in8the second cross. Partial dominance,
towards the higher parent was found for fruiting period and first
flowering node in the first cross. Partial dominance, towards the lower
parent was found for flowering date in the second cross, and maturity
date in the first cross.
The additive and dominance genetic effects were significant for all
traits, except the first fruiting node and number of branches per plant.
The epistatic gene effects seemed important for most traits studied.
Genetic coefficient of variation expressed moderate values for first
flowering and fruiting node, number of branches per plant and plant
height. However, flowering date, maturity date andfruiting period had
low genetic coefficient of variation. High to moderate heritability
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