الفهرس 
Introduction
The native home of the plantOnly 14 pages are availabe for public view
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Abstract
a.) This study was carried out during the growing seasons of 2002 and 2003 in a private vineyard located at Boktars village, near Aga city, Dakahlia Governorate on 12 years old Thompson Seedless grapevines. Spaced at 1.5 X 2.5 meters and trained according to the cane system normal trellis system. The study was designed to investigate vine response to nitrogen fertilization under different amounts and thus supplying growers with adequate information necessary to circumvent the problems encountered with current fertilizing practices of Thompson Seedless grapevines in order to develop the optimal amount required to attain optimum growth and maximum productivity with high fruit quality and high bud fertility. The amount of each treatment of the essential plant nutrient (N) were calculated on an annual basis of 80, 100, 120 and 140 unit N/fed. and added throughout the growing season on four stages (before flowering, after fruit set, after two weeks and post harvest). This study revealed the following results : 1 The number of bursted buds and bud burst percentage appear to decrease by increasing the dose of nitrogen applied. Vines applied with 140 units of nitrogen resulted in a more decrease in that respect (51.1 and 75.3%). whereas, it was 55.35 and 81.4 % under control treatment (80 units N/fed.). 2 The percentage of bud fertility as estimated as filed readings and microscopic procedure were decreased significantly with increasing the nitrogen rate, since the applications of 140 unit N/fed. were the lowest in both seasons of the study. whereas, applications 80 unit N/fed. gave the highest values in this respect. 3 An increase in leaf area was attained when N was applied at 80 and 100 unit/fed. during the two seasons compared with the other treatments used which decreased the leaf area. 4 The yield of Thompson Seedless grapevine expressed as kg/vine was the highest 8.48 kg/vine at N rate 80 units average of both of the study and then tend to decrease by increasing the rates of applied N, reached to 5.9 kg/vine at the 140 N units as an average of the two seasons of the study. 5 Excessive rates of N application decreased significantly the number of clusters per vine from 20.4 cluster per vine to 15.5 cluster per vine as an average of both seasons of the study. But, 80 unit N/fed. gave the highest values in this respect. 6 Berry weight and berry diameter had great fresh weight and diameter as received N at lower rates 80 N units, by increasing the N rates it was obvious that a decrease pattern was observed in the two seasons of the study. 7 Soluble solids, berries produced on vines applied with low nitrogen rate (80 N units), were 17.3, whereas the higher doses of N (140 N units) were lower 16.7 as an average of the two seasons of the study