الفهرس 
Vegetative traits of pumpkin
Data recorded Vine lengthOnly 14 pages are availabe for public view
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Abstract
The present investigation represent an attempt to study the genetic behavior of some morphological and yield traits as vine length, number of branches per vine, number of leaves per vine, number of fruits per vine, fruit weight, yield, fruit diameter, fruit length, fruit thickness and cavity length and diameter.
In this way, complete diallel crosses was performed included four inbred linesnamely, Long Island Cheese(P1),Tan Cheese (P2), Golden Hubbard (P3), Waltham Butternut (P4). These inbred lines were shown in such a way to represent most of the variation existing in these plants.
The following represents a brief resume of the obtained results:
1. All studied traits were influenced by both the additive and non- additive gene action.
2. Various types of dominance, viz., over ± dominance, partial dominance andnearly absence of dominance characterized the action of genes controlling the studied traits.
3. Vine length and number of fruits per vine showed, significantly, positive heterosis over mid and high parent, as indicated by the potence ratio, over dominance towards the higher parent.
4. The values of potence ratio in fruit diameter and length were very low and /or negligible, indicating that the additive gene action plays animportant role in the inheritance of fruit diameter trait.
5. For number of leaves per vine, nine and eight crosses exhibited significant heterosis in positive direction over both mid parent and high parent, respectively, while the crosses P2×P3,P3×P1 and P3×P4 showed significant heterosis in negative direction over mid and high parent. As indicated by potence ratio, over dominance towards the higher parent was shown in P1 ×P2, P1 ×P3, P2 ×P1, P2 ×P4, P3 ×P2, P4 ×P1 and P4 ×P2. Both crosses P1 ×P4and P4 ×P3 showed complete dominance towards the lowest parent.
6. For average fruit weight,ten crosses, namely, P1×P2, P1×P3, P1×P4, P2×P1, P2×P3, P2×P4, P3×P1, P3×P2, P4×P1 and P4×P3 showed highly significant and positive estimates of heterosis for average fruit weight trait over mid parents. Six crosses, namely, P1×P3, P2×P1, P2×P4, P3 ×P1, P4×P1 andP4×P3 showed highly significant and positive estimates of heterosis for average fruit weight trait over highparents
7. For flesh thickness, six crosses, namely, P3×P4, P4×P1, P4×P2, P4×P3 P1×P3 and P2×P1exhibited positive significant heterotic effect over mid parent, Five crosses showed partial dominance towards the highest parent, as well as , P1×P3, P2×P1,P3×P1and P4×P1showed over dominance towards the highest parent.
8. As for cavity length,the crossesP1×P4, P3×P1, P4×P1 and P4×P3showed significant heterosis in negative direction over mid parents, while, crossesP1×P4,P2×P3, P3×P1, P3×P2, P3×P4, P4×P1 and P4×P3showed significant heterosis in negative direction over high parents. Seven crosses showed partial dominance towards the lowest parent while, P1×P2, P2×P1,P2×P4 and P4×P2showed over dominance towards the highest parent, as well as,P3×P1showed over dominance towards the lowest parent.
9. As for cavity diameter,the crossesP1×P3, P1×P4 and P4×P3showed significant heterosis in negative direction over mid parents, while, crossesP1×P3,P1×P4, P2×P3, P3×P2, P4×P1, P4×P2 and P4×P3showed significant heterosis in negative direction over high parents. Three crosses showed partial dominance towards the lowest parent whileP4×P1 and P4×P2partial dominance towards the highest parent, P1×P2, P2×P1,P2×P4,P3×P1 and P3×P4showed over dominance towards the highest parent, as well as,P1×P3 and P1×P4showed over dominance towards the lowest parent.
10. Nine crosses, namely, P1×P2, P1×P3 , P1×P4, P2×P1, P2×P3, P2×P4, P3×P1, P3×P2and P4×P3 showed highly significant and positive estimates of heterosis for yield per vine trait over mid parents,while,eight crosses, namely, P1×P2, P1×P3, P2×P1, P2×P3, P2×P4,P3×P1,P3×P2 andP4×P3 showed highly significant and positive estimates of heterosis for yield per vine trait over highparents,nine crosses showed over dominance towards the highest parent,while,P3× P4 over dominance towards the lowest parent, P4× P2showed partial dominance towards the highest parent, as well as,P4× P1 showed partial dominance towards the lowest parent.
Combining ability analysis was done for all studied traits in a complete diallel set; the following results could be summarized:
1. For vine length, the only P2 had significant positive G.C.A. effects and both P1 and P4 had significantly negative G.C.A. effects, the positive S.C.A. effects were recorded by the crosses P2×P3, P1×P2, P3×P4, P1×P3 and P1×P4, while,Estimates of reciprocal effects for vine length the cross P4×P1 showed significant positive effects.
2. The G.C.A. effects for P3 showed significant positive effects for number of branches per vine, while, P1 showed significant negative effects. For S.C.A. effects,the cross P1×P3 showed significant positive effect for number of branches per vine,while the crosses P1×P4, P2×P4and P3×P4 showed negative effects. Estimates of reciprocal effects, the cross P3×P1 showed negative effects.3. Estimation of G.C.A. effects indicated thatP2 and P4 showed highly significant positive effects forleaves number, while, it was highly significant negative effects for P1 and P3. The crosses P1×P3, P2×P3, P2×P4 and P3×P4 exhibited the highest positive significant S.C.A.,while, both P1×P2 and P1×P4showed significant negative effects for number of leaves per vine. Estimates of reciprocal effects were highly significant positive for P3×P1 and P4×P3 crosses.
4. As for flesh thickness,the significant positive G.C.A. effects were observed for only one parent P4 and negative G.C.A. effects were observed for three parents. The significant positive S.C.A. effects were observed for three parents.Estimation of reciprocal effects for this trait showed significant positive effects in two crosses andsignificant negative effects in two crossesfor flesh thickness.
5. Concerning the significant G.C.A. effects for fruit length,only P4 favorable positive significant G.C.A. effects, while both P1 and P3 had undesirable significantly negative G.C.A. effect for this trait. The significant S.C.A. effects, only two hybrids P1×P4 and P2×P3 were positively significant and threehybrids P1×P2,P1×P3and P3×P4 were negatively significant. Estimates of reciprocal effects were significant positive for two crosses and negative for three crosses, viz., P2×P1, P4×P1and P4×P2.
6. The G.C.A. effects for fruit diameter were not significant for four parents, the S.C.A. effects were significant for two crosses had positive S.C.A. effects in unfavorable direction and four crosses had negative favorable specific combining ability effects.Estimation of reciprocal effects, the cross P3×P1 showed positive significant value, while,the crosses P2×P1 and P4×P2 showed negative significant values.7. As for cavity length two parents had positive G.C.A. effects in the unfavorable direction. Two parents P1 and P2 had significant G.C.A. effects and the favorable negative direction was exhibited by P3and P4 parents,two crosses had positive significant S.C.A. effectsin undesired positive direction and three hybrids out of these exhibited desirable significant negative S.C.A. effects. The negatively higher S.C.A. effects were observed in P1×P2, P1×P4 and P2×P3.The negatively higher R.C.A. effects were observed in P2×P1 and P4×P1.
8. As for cavity diameter,the G.C.A. effectswerethe favorable negative direction was exhibited by 2 parents. These two parents P3 and P4 had significant negative G.C.A. effects. Two parents P1, P2 had positive significant G.C.A. effects. Four hybrids exhibited desirable significant negative S.C.A. effects and two crosses had positive significant S.C.A. effects. The negatively higher R.C.A. effects were observed in P2×P1, P4×P1 and P3×P2.
9. Only one parent (P3) showed favorable significant positive general combining ability effects for number of fruits per vine.The significant S.C.A.effectswere recorded for 4 crosses, of which, two cross combinations had significant negative S.C.A. effects and two had significant positive S.C.A. effects for fruits number,estimates of reciprocal effects for fruits number were highly significant positive for four crosses. On the other hand, it was highly significant negative for P3×P1 and P4×P3 crosses.
10. For fruit weight, the G.C.A. effects of the parent P4 were found to be significant and positive, while, the parent P1 was found to be significantly and negative. Significant specific combining ability effects were observed two crosses exhibiting positive and four crosses exhibiting negative significant effects, respectively. The crosses P3×P1,P4×P2and P4×P3exhibiting significant positive R.C.A. effects for the trait.
11. As for yield per vine,one parent P4 exhibited positive general combining ability effects had significant positive and one parent P1 had significant negative effects. The significant specific combining ability effects were observed for 5 hybrids, of which one cross P2×P3 exhibited positive and four crosses P1×P2, P1×P4, P2×P4 and P3×P4exhibited negative effects for the yield per vine. Onecross exhibited significantly highest positive R.C.A. effects, two crosses exhibited significantly highest negative R.C.Aeffects P2×P1 and P3×P1.