الفهرس 
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Abstract
INTRODUCTION
Cotton is one of the most important crops in the world, and the main crop in Egypt. It is mainly culti¬vated for its fibers, however, many of its by-products are of great importance; e.i, cotton seeds. The culti¬vated area in Egypt represents about 1.2 million feddans which produces 12.5% of the world cotton production. Because of its competition with the other cotton varie¬ties, Egyptian cotton yield should be improved. This improvement depends basically on improving the cotton varieties by good breeding techniques, by using better nutrients and by keeping different pests under control. Also. This improvement includes supplying the soil with three of the most important elements. These are nitrogen, phosphorus and potassium. The existence of these elements leads to obtain high crop production.
Soils of Egypt contain very little nitrogen; usually less than 0.1%.
Nitrogen fertilizer may be leached and lost from the soil in gaseous forms either as ammonia and or Nitrogen gas by denitrification. The effectiveness of fertilizer nitrogen may also be reduced by other factor5. e.i., sali¬nity of the soil, limited supply of other nutrients, low plant population due to insect infestation and adverse seasonal conditions.
However, better management practices of nitrogen ferti-
lization are needed for increasing fertilizers effi¬ciency.
In recent years, fertilizers are applied as foliar spray for supplying significant ammounts of macro and micro nutrients to plants.
The present study is carried out to compare the effect of foliar and side dressing application of urea and a commercial foliar fertilizer; named folifertil, on the yield, yield components and some cotton fiber pro¬perties of Giza 70 cultivar.