Trials were conducted using paclobutrazol (PP333) either as a foliar application or a soil drench to improve berry set and yield of ‘Roumi Red’ grapes (Vitis vinifera L.). Concentrations of 100 and 250 ppm (foliar applications) and 2 ml/vine as a ground application had no effect on either chlorophyll and carotenoid leaf content or physical and chemical properties of berries, other than cluster weight and number of berries/cluster, which increased significantly. Concentrations of 1000, 1500, and 2000 ppm and 4 ml/vine reduced shoot and internode length as well as °Brix, whereas physical and chemical properties of berries, bud fertility, chlorophyll, and carotenoid leaf content were increased. A carry-over effect was noticed the year following the year of application with concentrations of 750 ppm and 3 ml/vine or higher. Chemical name used: β[(4-chlorophenyl)methyl]-α-(1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).

This study was conducted during 1997 and 1998 seasons on Flame seedless grapevines grown in a sandy soil to examine the effect of mineral or chelated calcium and magnesium on bunch and berry characteristics. The effect of spraying Ca-EDTA and Mg-EDTA each at 0.15 and 0.30% as well as calcium chloride and magnesium sulphate each at 0.5 and 1.0% was investigated.Results showed that foliar application of calcium and magnesium either chelated or mineral forms was very effective in increasing bunch and berry weight, dimensions of berry and bunch, number of berries/bunch, berry weight and firmness and skin anthocyanin content as compared to unspraying. Calcium and magnesium treatments had a slight effect on berry shape, total soluble solids and total acidity. In most cases, the application of chelated form of each macronutrient was preferable than application of mineral form in improving most of the studied characters. Foliar application of Mg-EDTA at 0.30% surpassed that of Ca-EDTA in increasing bunch weight, number of berries per bunch, berry weight and dimensions and skin anthocyanins content. However, spraying Ca-EDTA at 0.30% was the more effective in increasing bunch dimensions and berry firmness, than that of Mg-EDTA at the same concentration.The best results with regard to bunch and berry characteristics of Flame seedless grapevines were obtained due to spraying Mg-EDTA at 0.30% or Ca-EDTA at 0.30% three times on March 15 th , May 1 st and June 15 th .

This experiment was carried out during 1997 and 1998 seasons on Flame seedless grapevines grown in a sandy soil to throw some light on the effect of spraying mineral or chelated compounds of Ca and Mg on growth and chemical composition of leaves and canes. Nine treatments i.e control, calcium chloride at 0.5 and 1.0 %; Ca-EDTA at 0.15 and 0.30%, magnesium sulphate at 0.5 and 1% and Mg-EDTA at 0.15 and 0.3 % were involved. The vines received three sprays of Ca and Mg (i.e March 15 -th ; May 1 -st and June15 th )Results showed that foliar application of chelated compounds at 0.15 to 0.30% as well as mineral compounds at 0.5 to 1.0 % from Ca and Mg was favourable in improving all growth parameters, leaf pigment content, leaf content of Ca and Mg and cane content of total carbohydrates compared to unsparing. Chelated form of each macronutrients was surpassed the mineral one in enhancing most of the studied characteristics. Shoot length, internode length, leaf area, cane thickness, chlorophyll A and B and cane total carbohydrate contents were positively affected by the application of Mg-EDTA at 0.30%. Application of Ca-EDTA at 0.3% had a promising effect on number of leaves per shoot and weight of pruning wood.The best results with regard to growth and nutritional status of Flame Seedless vines were obtained by spraying 0.3% Mg-EDTA or 0.3% Ca-EDTA three times during the growing season .