الفهرس 
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Abstract
This study was carried out during 2006/ 2007 and 2007/ 2008 seasons on ninety- six mature self- rooted 5- years old cane trained Superior grapevines. The selected vines were chosen as uniform in vigour as possible and grown in Sohag Fac. of Agric. Experimental orchard situated at El- Kawthar region, Sohag Governorate. The texture of the vineyard soil is sandy and the soil is well drained water, since water table depth is not less two meters. The chosen vines are spaced at 1.75 x 2.5 meters apart. Cane pruning was followed on the last week of December in both seasons with the assistance of shape supporting system. The vines were irrigated through drip irrigation system.
All the chosen grapevines received regular and horticultural practices that already were carried out in the vineyard except those dealing with vine load and Dormex application.
This study involved three factors ( A & B & C ). The first factor (A) consisted of two vine bud loads namely a1) Leaving 60 eyes per vine ( 6 fruiting cans x eight eyes plus six renewal spurs x 2 eyes) and a2) Leaving 84 eyes per vine (6 fruiting canes x twelve eyes plus six renewal spurs x two eyes). The second factor (B) included the following four dates of spraying Dormex:
b1) Spraying Dormex on 30 Dec.
b2) Spraying Dormex on 10 Jan.
b3) Spraying Dormex on 20 Jan.
b4) Spraying Dormex on 30 Jan.
The third factor (C) contained four concentrations of Dormex namely C1) 0.0 %, C2) 1.5 %, C3) 3.0 % and C4) 4.5 % . Therefore, the experiment involved thirty- two treatments. Each treatment was replicated three times, one vine per each.
A complete randomized block design in split – split plot arrangement was followed. The two vine bud loads occupied the main plots, the four dates of Dormex application ranked the sub- plots and the four concentrations of Dormex allocated the sub- sub- plots.
During both seasons, the following parameters were measured:
1- Measurements of behaviour of buds namely time of bud burst as well as percentages of bud burst and fruiting buds .
2-Measurements of vegetative growth characters namely, main shoot length (cm.), number of leaves on each main shoot, leaf area (cm)2, cane thickness (cm.) and weight of pruning wood per vine (kg.)
3-Date of first bloom.
4-Measurements of plant pigments namely chlrophylls a and b and total chlorophylls (mg/ 1.0 F.W.) in the leaves .
5-Percentage of berry setting..
6-Date of harvesting
7-Yield per vine expressed in weight (kg.) and number of clusters per vine.
8-Cluster weight (g.) and dimensions ( length and width in cm.)
9-Percentage of shot berries
10-Measurements of physical and chemical characters of the grapes namely berry weight (g.) and dimensions ( equatorial and longitudinal in cm); total soluble solids %, total acidity %, total sugars % and total soluble solids / acid.
The summary of the obtained data in both seasons could be outlined under the following main items.
1-Behaviour of buds:-
Varying vine loads failed to show measurable effect on the time of bud burst but had an obvious effect on percentages of bud burst and fruiting buds. leaving 84 eyes per vine during winter pruning materially increased percentages of bud burst and fruiting buds rather than selecting 60 eyes/ vine.
Application of Dormex on 10 or 20 Jan effectively advanced the time of bud burst as well as improved percentages of bud burst and fruiting buds compared to the other dates of application. Spraying Dormex on 30 Jan. obviously delayed bud burst and gave the minimum values of bud burst and fruiting buds.
There was a gradual enhancement on the time of bud burst as well as percentages of bud burst and fruiting buds with increasing Dormex concentrations from 1.5 to 4.5% . Increasing Dormex concentrations from 3.0 to 4.5 % caused meaningless promotion.
Pruning to leave 84 eyes / vine as well as spraying Dormex on 10 Jan. at 4.5% effectively maximized percentages of bud burst and fruiting buds. Untreating the vines with Dormex with leaving 60 eyes / vine during winter pruning gave the lowest values.
2-Vegetative growth characters:
Vegetative growth characters namely main shoot length, number of leaves per main shoot, leaf area, cane thickness and wood prunings per vine were obviously stimulated with leaving 60 eyes/ vine rather than selecting 84 eyes / vine.
Treating the vines with Dormex on 10 Jan followed by spraying on 20 Jan resulted in the highest values. The minimum values were recorded on vines treated with Dormex on 30 Jan.
There was a gradual promotion on these growth traits with increasing Dormex concentration from 1.5 to 4.5 %. A slight stimulation on these growth aspects was recorded when Dormex concentrations was increased from 3.0 to 4.5 %.
Leaving 60 eyes per vine accompanied with treating the vines with Dormex at 4.5 % on 10 Jan. noticeably enhanced vegetative growth characters.
3- Date of first bloom:
Number of eyes left per vine during winter pruning had no effect on the date of first bloom.
Spraying Dormex on 10 Jan ,. 20 Jan, 30 Dec. and 30 Jan, in descending order advanced the date of first bloom. Date of first bloom, was greatly delayed when the vines were sprayed with Dormex on 30 Jan.
The great enhancement on the date of first bloom was observed on the vines treated with Dormex at 1.5 to 4.5 % rather than non- application. The advancement was associated with increasing Dormex concentrations. Increasing Dormex concentrations from 3.0 to 4.5 % had meaningless promotion on the date of first bloom.
A clear and remarkable stimulation on the date of first bloom was recorded on the vines borne 60 or 84 eyes per vine and treated with Dormex at 3.0 % on 10 Jan.
4-Plant pigments:
Chlorophylls a and b as well as total chlorophylls were positively affected with lowering vine load from 84 to 60 eyes/ vine.
These plant pigments were remarkably enhanced with spraying Dormex on 10 Jan, 20 Jan, 30 Dec. and 30 Jan, in descending order.
Increasing concentrations of Dormex was followed by a progressive increment on plant pigments. A slight increase on these pigments was observed when concentration of Dormex was increased from 3.0 to 4.5 %
Selecting 60 eyes / vine and spraying Dormex at 4 % on 10 Jan gave the maximum values.
5- Percentage of berry setting:
A considerable promotion on the percentage of berry setting was observed with leaving 60 eyes / vine compared to selecting 84 eyes/ vine.
Treating the vines on 10 Jan with Dormex gave the maximum values compared to spraying on the other dates. The lowest values were recorded on vines treated on 30 Jan.
There was a gradual promotion on percentage of berry setting with increasing Dormex concentrations.
Leaving 60 eyes/ vine and spraying Dormex on 10 Jan. at 3.0% effectively maximized percentage of berry setting.
6- Date of harvesting:
Varying vine loads had no effect on date of harvesting. Spraying Dormex on 10 Jan or 20 Jan. effectively advanced the date of harvesting compared to spraying on 30 Dec. or 30 Jan. Treating the vines with Dormex on 10 Jan. gave an early promotion on the date of harvesting date.
There was a gradual hastening on the date of harvesting with increasing concentrations of Dormex. Increasing concentrations of Dormex from 3.0 to 4.5 % failed to show measurable advancement on the date of harvesting.
Leaving 60 or 84 eyes/ vine along with treating the vines on 10 Jan. with Dormex at 3.0 % obviously accelerated the date of harvesting.
7- Yield as well as cluster weight and dimensions:
Yield expressed in weight (kg.) and number of clusters per vine was positively affected by leaving 84 eyes/ vine compared to leaving 60 eyes/ vine. Increasing number of eyes left per vine was followed by decreasing weight and dimensions of cluster.
Treating the vines with Dormex on 10 Jan, 20 Jan., 30 Dec. and 30 Jan., in descending order improved the yield expressed in weight and number of clusters per vine (in the second season) and weight and dimensions of cluster. The maximum values were recorded on the vines treated with Dormex on 10 Jan. Spraying on 30 Jan. gave the minimum values.
There was a gradual stimulation on the yield as well as cluster weight and dimensions with increasing Dormex concentration. No measurable promotion was observed on the yield as well as cluster weight and dimensions when Dormex concentration was increased from 3.0 to 4.5 %. Therefore, the suggested concentration from economical point of view was 3.0%.
The best results with regard to yield were obtained when the vines were pruned to leave 84 eyes/ vine as well as when they treated with Dormex at 3.0 % on 10 Jan.
Number of clusters / vine did not alter with changing dates and concentrations of Dormex in the first season of study.
8- Percentage of shot berries
Reducing vine load from 84 to 60 eyes/ vine was accompanied with increasing percentage of shot berries.
Treating the vines with Domex on 10 and 30 Jan. resulted in the minimum and maximum percentage of shot berries, respectively. There was a gradual reduction on percentage of shot berries with increasing Dormex concentration. There was a slight reduction with increasing Dormex concentrations from 3.0 to 4.5 %.
The minimum percentage of shot berries was recorded on clusters picked from vines borne 84 eyes / vine and treated with Dormex at 4.5 % on 10 Jan.
9- Physical and chemical characters of the grapes :
Selecting 60 eyes / vine considerably improved berry weight and dimensions compared to leaving 84 eyes/ vine. Varying vine loads had no effect on chemical quality of the grapes.
Treating with vines with Dormex on 10 Jan. resulted in the highest physical and chemical quality characters of the grapes. Spraying the vines on the previous date with Dormex effectively improved quality of the berries in terms of increasing berry weight and dimensions, total soluble solids, total sugars and total soluble solids / acid and in decreasing total acidity. Unfavorable effects on quality of the berries were recorded when the vines were treated with Dormex on 30 Jan.
There was a remarkable promotion on physical and chemical characters of the grapes with increasing Dormex concentrations. Increasing Dormex concentrations from 3.0 to 4.5 % had no material promotion on physical and chemical quality of the grapes. Therefore, the suggested concentration was 3.0 %.
A striking effect on physical and chemical characters of the grapes was observed on the vines borne 60 eyes/ vine and treated with Dormex at 3.0 % on 10 Jan. It is worth to mention that treating the vines that borne 84 eyes / vine with Dormex at 3.0 % on 10 Jan effectively improved quality of the berries than leaving 84 eyes/ vine without spraying Dormex.
Conclusion :
Carrying out cane pruning by leaving 84 eyes/ vine (six fruiting canes x twelve eyes plus six renewal spurs x two eyes) on the last week of Dec. as well as spraying Dormex at 3.0 % on 10 Jan. was beneficial for obtaining an economical yield advancing harvesting date, controlling shot berries and producing fairly good quality of Superior grapes growing under Sohag conditions. Application of such promised treatment in one feddan contains 915 vines achieved expected net profit reached 6540 and 9580 Egyptian pounds over the check treatment during 2006/ 2007 and 2007/ 2008 seasons, respectively as previously mentioned in the Table (29) in the results.