الفهرس 
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Abstract
This study was carried out during 1999/2000, 2000/2001, 2001/2002 and 2002/2003 growing seasons at Etay El-Baroud Agricultural Research Station, Behaira Governorate, Egypt. The objective of this study was to estimate the response to different methods of plant breeding i.e., pedigree, bulk and single pod descent. Also, direct and indirect selection criteria for increase seed yield were carried out. A selection intensity of 5% was used with direct selection (selection for yield itself) and with indirect selection using the three criteria, i.e., no. of pods/plant, 100-seed weight, no of seeds/pod. The genetic parameters were estimated in F3, F4 and F5 generations.
Two F2 populations derived from the crosses (line 109 x G461), and (G. 714 x G. 716). The results could be summarized as follows:
A) The first cross (line 109 x G. 4861):
1.Mean square associated with F3 families was found to be significant for all studied traits except no. of seeds/pod.
2.Genetic gain was high for no. of pods/plant and moderate for seed yield/plant, while, low gain from selection was detected for 100-seed weight. The same trend was obtained for G.C.V.% for these traits in the F3 families.
3.Most selected families surpassed significantly the better parent for seed yield/plant in the F4 families. Also, genetic gain was rather low for no. of pods/plant and 100-seed weight. Moderate genetic gain was observed for seed yield/plant. The
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same trend was obtained for G.C.V.% for the mentioned traits.
Finally, it could be concluded that indirect selection for
yield via no. of pods/plant and selection for yield itself were effective.
4. F5 generation:
a)Breeding methods:
Mean squares due to breeding methods were significant for 100-seed weight and seed yield/plant. The pedigree method gave consistently more superior compared the best parent with nine lines followed by bulk and SPD with five lines. The best line was no. 8 for SPD method (137.72 g/plant), line no. 7 for bulk method with (128.64 g/plant) then line no. 3 for pedigree method with (126.86 g/plant).
b)Selection criteria:
Mean squares due to four selection criteria i.e. no. of
pods/plant, 100-seed weight, no. of seeds/pod and seed yield/plant were significant.
Concerning seed yield/plant, the selection with high no. of pods/plant gave significant higher value of this trait, followed by selected plants with high seed yield/plant. However,
selected plants with high no. of seeds/pod recorded the lowest one.
B) The second cross (G. 714 x G. 716):
I. Mean squares due to F3 families was highly significant for all studied traits. For seed yield/plant, six families surpassed
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significant the best parent G. 716. Family no. 2 followed by 28 were the best among them.
2.Heritability values were detected for no. of pods/plant and 100-seed weight but moderate for seed yield/plant. However, low value was found for no. of seeds/pod. High genetic gain value was detected for no. of pods/plant. However, moderate values for 100-seed weight and seed yield/plant, but low for no. of seeds/pod.
3.Twenty nine families exceeded significantly the better parent of seed yield/plant in the F4 generation.
4.F5 generation: a) Breeding methods:
Mean squares due to breeding methods were significant for all studied traits except seed index. The bulk method gave the highest values for no. of seeds/pod and seed yield/plant. While SPD exhibited significantly high no. of pods/plant. I Iowever, no differences between the three breeding methods for seed index. It could be concluded that bulk method considered as the best breeding method for no. of seeds/pod and seed yield/plant than those for pedigree and SPD in this cross. Regarding seed yield/plant, the range of selected lines varied from 60.01 (line no. 8 in pedigree) to 112.71 (line no. 1 in bulk method). Bulk method was the best method whereas gave four superior lines compared to better parent or grand mean, followed by SPD method.
h) Selection criteria:
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Mean squares due to four selection criteria i.e. no. of pods/plant, 100-seed weight, number of seeds/pod (indirect selection) and seed yield/plant (direct selection) were significant: Concerning seed yield/plant, the selection method of heavier seed index exhibited significantly higher value of this trait followed by selection plants with higher seed yield/plant or no. of pods/plant. It could be concluded that indirect selection for yield via heavier seed index is more efficient than direct selection for yield.
For seed yield/plant, three and three, six and six, zero and one and one and one lines were significantly higher seed yield/plant than grand mean and better parent when selected plants depend on high number of pods/plant, heavier seed index, number of seeds/pod and high seed yield/plant, respectively. The best lines were no. 4 with (142.96 g) and no. 3 with (124.30 g) followed by no. 5 with 106.39 g) when selection based on heavier seed index.