Abstract:
The present investigation was carried out under insect-free
cages during the three successive seasons 2004-2006. A diallel cross excluding
reciprocals among eight faba bean genotypes was used to estimate the heterotic
effects of F1 crosses and F2 populations relative
to their respective mid and better parents and combining ability analysis
for yield and some of its variables. Highly significant differences among
the tested entries were detected for different traits, indicating wide
genetic variability for all traits. Heterosis percentages relative to
mid-parents were significantly positive in several crosses with a range
of 15.6-19.7, 38.0-59.8, 85.0-131.4, 74.3-79.4, 54.4-127.2 and 69.8-142.0%
for plant height, number of branches per plant, number of pods per plant,
number of pods per main stem, number of seeds per plant and seed yield
per plant, respectively. However, heterosis percentages relative to better
parent were significantly positive in some crosses and recorded a range
of 19.0-19.0, 54.2-73.7, 62.9-97.7 and 47.6-129.9% for plant height, number
of pods per plant, number of seeds per plant and seed yield per plant,
in the same order. Some crosses exhibited significantly negative heterosis
compared to respective mid-parent for days to flowering (from -9.0-23.5%).
The ratios of