الفهرس 
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Abstract
This study was carried out during 2016 and 2017 seasons on 54 uniform in vigour 10-years old own- rooted Red Globe grapevines. The selected vines are grown in a private vineyard located at Al- Kessey private vineyard located at Matay district, Minia Governorate, where the texture of the soil is clay. The selected vines are planted at 1.5 x 3 meters apart. The chosen vines were trained by spur pruning method leaving 66 eyes/ vine (on the basis of 18 fruiting spurs x 3 eyes plus 6 replacement spurs/ two eyes) using Gable supporting system. Winter pruning was carried out at the first week of Jan. during both seasons. Surface irrigation system was followed using Nile water. The selected vines received the common horticultural practices that already applied in the orchard except those dealing with spraying silicon and summer pruning practices.
This study was planned for examining the effect of spraying silicon and some summer pruning treatments on some growth aspects, vine nutritional status, yield, berries colouration % and berries quality of Red Globe grapevines growing under upper Egypt conditions .
This study consisted from the following nine treatments:
1- Control treatment.
2- Spraying potassium silicate at 0.1% (g/l)
3- Spraying potassium silicate at 0.1%+ pinching the main shoots
4- Spraying potassium silicate at 0.1%+ removing all leaves under clusters.
5- Spraying potassium silicate at 0.1%+ removing all laterals on the main shoots.
6- Spraying potassium silicate at 0.1%+ pinching the main shoots + removing all leaves under clusters.
7- Spraying potassium silicate at 0.1%+ pinching the main shoots+ removing all laterals on the main shoots.
8- Spraying potassium silicate at 0.1%+ removing all leaves under clusters+ removing all laterals on the main shoots.
9- Spraying potassium silicate at 0.1%+ all summer pruning practices (pinching the main shoots, removing all leaves under clusters and removing all laterals on the main shoots.
Each treatment was replicated three times, two vines per each. The total vines selected for achieving of this experiment were 54 vines. Pinching the main shoots was carried once by cutting 3 cm from shoot tips. Summer pruning practices were conducted once just after berry setting (middle of May). Potassium silicate (25% Si+ 10% K2O) was sprayed three times at growth start (middle of April), just after berry setting (middle of May) and at one month later (middle of June). Triton B as a wetting agent at 0.1% was added to silicon solutions and spraying was done till runoff.
The experimental design was randomized complete block design RCBD with nine treatments, each with three replicates, two vines per each.
During both seasons, the following parameters were recorded:
1- Some vegetative growth aspects namely leaf area (cm2), number of leaves/shoot, wood ripening coefficient, cane thickness (cm) and pruning wood weight/vine (Kg).
2- Leaf pigments namely chlorophylls a & b, total chlorophylls and total carotenoids (as mg/ g F.W.), N, P, K, Mg and Ca (as %) and Zn, Fe and Mn (as ppm) on the petioles of the leaf (on dry weight basis).
3- Yield/vine expressed in weight (Kg) and number of clusters/ vine.
4- Weight (g), length and shoulder (cm) of cluster.
5- Percentage of berries colouration.
6- Physical characteristics of the berries namely weight (g) and dimensions (longitudinal and equatorial) (cm),
7- Chemical characteristics of the berries namely T.S.S. %, total acidity % (as g tartaric acid/100 ml juice), reducing sugars % and total anthocyanins in the berries (mg/100 g F.W.).
The nearly same trend of the obtained data during both seasons could be summarized under the following main items:
1-Vegetative growth aspects:
The five vegetative growth aspects namely leaf area, number of leaves/shoot, wood ripening coefficient, pruning wood weight and cane thickness were remarkably stimulated due to spraying potassium silicate at 0.1% either alone or in combined with any summer pruning treatments (pinching the main shoots, removing all leaves under clusters and removing all laterals on the main shoots) relative to the control treatment. Using potassium silicate with any summer pruning treatments was preferable than using potassium silicate alone. The best summer pruning practices applied with silicon were removing all laterals on the main shoots, removing all leaves under clusters and pinching the main shoots, in descending order. The maximum values were recorded when the vines received potassium silicate and the three summer pruning practices together.
2- Leaf chemical components:
Spraying the vines with potassium silicate at 0.1% either alone or with any summer pruning treatments had an obvious stimulation on chlorophylls a and b, total chlorophylls, total carotenoids N, P, K Mg, Ca, Zn, Fe and Mn in the leaves relative to the control. The promotion on these leaf chemical components was relatively higher when the vines treated with silicon and any summer pruning treatments than using silicon alone. The best summer pruning treatments were removing all laterals on the main shoots followed by removing all leaves under clusters and the summer pruning practice namely pinching the main shoots ranked the last position in this respect. The best treatment was application of silicon with all summer pruning treatments.
3- Yield/ vine as well as weight and dimensions of cluster.
There was a remarkable promotion on yield expressed in weight and number of clusters/ vine as well as weight, length and shoulder of cluster with treating the vines with potassium silicate alone or in combined with any summer pruning treatments relative to the control. The promotion was materially associated with using the summer pruning practices namely removing all laterals on the main shoots, removing all leaves under clusters and pinching the main shoots, in descending order. Using silicon in combined with any summer pruning treatments was preferable in improving yield and cluster aspects than using silicon alone. The highest values were recorded on the vines that received silicon and all summer pruning treatments. The untreated vines produced the minimum values.
4- Percentage of berries colouration.
It was obviously enhanced by spraying potassium silicate at 0.1% either alone or in combined with any summer pruning treatments relative to the control treatment . Combined application of silicon with any summer pruning treatment was preferable than using silicon alone in this respect. The best summer pruning practices in enhancing berries colouration was removing all laterals in the main shoots, removing all leaves under clusters and pinching the main shoots, in descending order. The best colouration in the berries clusters was observed in the vines that received silicon and all summer pruning treatments.
5- Physical and chemical characteristics of the berries.
Single and combined applications of silicon and any summer pruning treatments were materially very effective in improving quality of the berries in terms of increasing berry weight and dimensions (equatorial and longitudinal), T.S.S%, reducing sugars% and total anthocyanins and decreasing total acidity % relative to the check treatment. The promotion was considerably related to removing all laterals in the main shoots, removing all leaves under clusters and pinching the main shoots, in descending order. Using silicon with any summer pruning treatments was favourable than using silicon alone in improving quality of the berries. The best results were obtained due to spraying the vines with potassium silicate at 0.1 % and all summer pruning treatments.