الفهرس 
Aim of workOnly 14 pages are availabe for public view
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Abstract
Objectives : 1- Fingerprints as obtained through protein electrophoresis technique and RAPD-PCR technique using random primers to squash parental lines. 2-Use two mating designs: factorial mating design and complete diallel crosses mating design to produce hybrids of squash. 3-The amounts of heterosis over the mid-parents and the better parent. 4-Genetic parameters and heritability in both broad and narrow senses. 5-General and specific combining abilities. 6-Estimating the genetic variances which including additive and dominance from both mating design would be determined according to the homogeneity test of variances. Methods & Results : 1-The genetic materials used in the present investigation included seven squash lines belong to the species (Cucurbita pepo, L.). These parental lines were: Eskandarani (P1) ; Zucca Patisson custard white (P2) ; All Green Bush (P3); Courgette Orelia (P4) ; Sakiz (P5) ; Copi (P6) and Gapla (P7). 2-The relationships among lines were made using fingerprints through protein electrophoresis technique and RAPD-PCR techniques. 3-Two mating designs were used. They were : factorial mating design for the seven squash parental lines three as males and the other four lines were used as females to produce 12 F1 hybrids. The second mating design was a complete diallel crosses mating design using all seven squash parental lines to produce 21 F1 hybrids and their 21 F1r reciprocal hybrids. 4- The polymorphic bands were scored as 8 unique bands. These unique bands were used to discriminate between the seven squash parents. In addition, the results generated from protein and RAPD profiles were pooled together to elucidate the genetic relationships among the seven examined parents. 5- The mean squares of GCA for all vegetative, earliness and yield and yield component traits were highly significant indicating that the additive genetic variances for these traits were important and of large magnitudes.Conclusion : Using protein and RAPD markers for characterization and construction of genetic linkage maps and the molecular genetic diversity of parents support the use of marker-assisted selection (MAS) in squash cultivars breeding programs. The results showed that the estimates of heterosis versus mid-parent and better parent showed highly significance for most studied traits. The magnitudes of (GCA) were larger than their corresponding estimates of (SCA) for most studied traits at both F1 and F1r hybrids for vegetative, earliness, yield and yield component traits. Estimation of genetic parameters showed that the additive genetic variance was very important for most studied traits. The importance of additive and non-additive genetic variance in addition to maternal effect played the major role in the inheritance of these traits. The estimates of heritability in both broad and narrow senses were larger in magnitudes than their corresponding values in narrow sense.